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51.
Wang Y Hosta-Rigau L Lomas H Caruso F 《Physical chemistry chemical physics : PCCP》2011,13(11):4782-4801
In recent years, interfacial properties have been tailored with nanostructured polymer assemblies to generate materials with specific properties and functions for application in diverse fields, including biomaterials, drug delivery, catalysis, sensing, optics and corrosion. This perspective begins with a brief introduction of the assembly techniques that are commonly employed for the synthesis of nanostructured polymer materials, followed by discussions on how the interfaces influence the properties and thus the functionalities of the polymer materials prepared. Applications of the interfacial polymer nanostructures, particularly for the immobilization and encapsulation of cargo, are then reviewed, focusing on stimuli-responsive cargo release from the polymer nanostructured assemblies for controlled delivery applications. Finally, future research directions in these areas are briefly discussed. 相似文献
52.
Narciso Martí-Oliet Miguel Palomino Alberto Verdejo 《Journal of Algorithms in Cognition, Informatics and Logic》2007,62(3-4):95-116
By means of several examples of structural operational semantics for a variety of languages, we justify the importance and interest of using the notions of strategies and simulations in the semantic framework provided by rewriting logic and implemented in the Maude metalanguage. On the one hand, we describe a basic strategy language for Maude and show its application to CCS, the ambient calculus, and the parallel functional language Eden. On the other hand, we show how the concept of stuttering simulation can be used inside Maude to show that a stack machine correctly implements the operational semantics of a simple functional language. 相似文献
53.
PabloJ. Linares‐Palomino G.K.Surya Prakash GeorgeA. Olah 《Helvetica chimica acta》2005,88(6):1221-1225
Methyl (R)‐glycidate (=methyl (R)‐oxiranecarboxylate; 2 ) in superacidic trifluoromethanesulfonic acid medium reacts with electron‐rich arenes to give α‐hydroxy‐β‐arylpropanoate derivatives 3a – 3f with high stereospecificity. At the same time, the observed high regioselectivity has been attributed to superelectrophilic activation of the glycidate. 相似文献
54.
55.
We study the strong coupling limit of U(N) or SU(N) gauge theories with fermions on a lattice. The integration over the gauge and fermion degrees of freedom is performed by analytic methods, leading to a partition function in terms of localized meson and baryon fields. A method for deriving a systematic expansion in the inverse of the space-time dimension of the corresponding Green functions is developed. It is applied to the study of spontaneous breakdown of chiral symmetry, which occurs for any U(N) or SU(N) theory with fermions in the fundamental representation. Meson and baryon spectra are then computed, and found to be in close agreement with those obtained by numerical methods at finite coupling. The pion decay constant is estimated. 相似文献
56.
Nachtigall P Garrone E Palomino GT Delgado MR Nachtigallová D Areán CO 《Physical chemistry chemical physics : PCCP》2006,8(19):2286-2292
The interaction, at a low temperature, between molecular hydrogen and the zeolite Li-FER was studied by means of variable temperature infrared spectroscopy and theoretical calculations using a periodic DFT model. The adsorbed dihydrogen molecule becomes infrared active, giving a characteristic IR absorption band (H-H stretching) at 4090 cm(-1). Three different Li(+) site types with respect to H(2) adsorption were found in the zeolite, two of which adsorb H(2). Calculations showed a similar interaction energy for these two sites, which was found to agree with the experimentally determined value of standard adsorption enthalpy of DeltaH(0) = -4.1 (+/-0.8) kJ mol(-1). The results are discussed in the broader context of previously reported data for H(2) adsorption on Na-FER and K-FER. 相似文献
57.
In this paper we introduce broccoli curves, certain plane tropical curves of genus zero related to real algebraic curves. The numbers of these broccoli curves through given points are independent of the chosen points — for arbitrary choices of the directions of the ends of the curves, possibly with higher weights, and also if some of the ends are fixed. In the toric Del Pezzo case we show that these broccoli invariants are equal to the Welschinger invariants (with real and complex conjugate point conditions), thus providing a proof of the independence of Welschinger invariants of the point conditions within tropical geometry. The general case gives rise to a tropical Caporaso–Harris formula for broccoli curves which suffices to compute all Welschinger invariants of the plane. 相似文献
58.
Hannah Schreyer Rene Eckert Sarah Immohr Jacopo deBellis Michael Felderhoff Ferdi Schüth 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(33):11384-11387
Supported catalysts are among the most important classes of catalysts. They are typically prepared by wet‐chemical methods, such as impregnation or co‐precipitation. Here we disclose that dry ball milling of macroscopic metal powder in the presence of a support oxide leads in many cases to supported catalysts with particles in the nanometer size range. Various supports, including TiO2, Al2O3, Fe2O3, and Co3O4, and different metals, such as Au, Pt, Ag, Cu, and Ni, were studied, and for each of the supports and the metals, highly dispersed nanoparticles on supports could be prepared. The supported catalysts were tested in CO oxidation, where they showed activities in the same range as conventionally prepared catalysts. The method thus provides a simple and cost‐effective alternative to the conventionally used impregnation methods. 相似文献
59.
Julian Tu Dennis Svatunek Saba Parvez Albert C. Liu Brian J. Levandowski Hannah J. Eckvahl Randall T. Peterson Kendall N. Houk Raphael M. Franzini 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(27):9141-9146
The isocyano group is a structurally compact bioorthogonal functional group that reacts with tetrazines under physiological conditions. Now it is shown that bulky tetrazine substituents accelerate this cycloaddition. Computational studies suggest that dispersion forces between the isocyano group and the tetrazine substituents in the transition state contribute to the atypical structure–activity relationship. Stable asymmetric tetrazines that react with isonitriles at rate constants as high as 57 L mol?1 s?1 were accessible by combining bulky and electron‐withdrawing substituents. Sterically encumbered tetrazines react selectively with isonitriles in the presence of strained alkenes/alkynes, which allows for the orthogonal labeling of three proteins. The established principles will open new opportunities for developing tetrazine reactants with improved characteristics for diverse labeling and release applications with isonitriles. 相似文献
60.
Loop mediated isothermal amplification (LAMP) is a nucleic acid amplification technique performed under isothermal conditions. The output of this amplification technique includes multiple different sizes of deoxyribonucleic acid (DNA) structures which are identified by a banding pattern on gel electrophoresis plots. Although this is a specific amplification technique, the complexity of the primer design and amplification still lead to the issue of obtaining false‐positive results, especially when a positive reading is determined solely by whether there is any banding pattern in the gel electrophoresis plot. Here, we first performed extensive LAMP experiments and evaluated the DNA structures using microchip electrophoresis. We then developed a mathematical model derived from the various components that make up an entire LAMP structure to predict the full LAMP structure size in base pairs. This model can be implemented by users to make predictions for specific, DNA size dependent, banding patterns on their gel electrophoresis plots. Each prediction is specific to the target sequence and primers used and therefore reduces incorrect diagnosis errors through identifying true‐positive and false‐positive results. This model was accurately tested with multiple primer sets in house and was also translatable to different DNA and RNA types in previously published literature. The mathematical model can ultimately be used to reduce false‐positive LAMP diagnosis errors for applications ranging from tuberculosis diagnostics to E. coli to numerous other infectious diseases. 相似文献