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71.
Xiaoling Zuo Fabrice Morlet‐Savary Bernadette Graff Nicolas Blanchard Jean‐Philippe Goddard Jacques Laleve 《Macromolecular rapid communications》2016,37(10):840-844
The photochemical and electrochemical investigations of commercially available, safe, and cheap fluorescent brighteners, namely, triazinylstilbene (commercial name: fluorescent brightener 28) and 2,5‐bis(5‐tert‐butyl‐benzoxazol‐2‐yl)thiophene, as well as their original use as photoinitiators of polymerization upon light emitting diode (LED) irradiation are reported. Remarkably, their excellent near‐UV–visible absorption properties combined with outstanding fluorescent properties allow them to act as high‐performance photoinitiators when used in combination with diaryliodonium salt. These two‐component photoinitiating systems can be employed for free radical polymerizations of acrylate. In addition, this brightener‐initiated photopolymerization is able to overcome oxygen inhibition even upon irradiation with low LED light intensity. The underlying photochemical mechanisms are investigated by electron‐spin resonance‐spin trapping, fluorescence, cyclic voltammetry, and steady‐state photolysis techniques.
72.
We give a variational formula for the solution of a Mixed Boundary Value Problem when the geometrical domain is perturbed (Hadamard's Variational Formula) ; we show that this formula contains singularities ; the result is used to construct a new approach to the optimal control problem for a problem related to a Signorini-like Elliptic Variational Inequality. 相似文献
73.
Maria Bernadette Donato Monica Milasi Antonio Villanacci 《Journal of Mathematical Analysis and Applications》2018,457(2):1353-1369
We deal with the analysis of the general equilibrium model with incomplete financial markets and nominal assets. We assume that there are 2 periods of time, say today and tomorrow. We define a consumption, portfolio holding, commodity and asset price vector as an equilibrium vector associated with a given economy if at those prices and economies households maximize utility under a budget constraints and markets clear. While the path breaking proofs of existence by Cass [6] and Werner [25] use a fixed point argument, we provide an independent existence proof in terms of variational inequalities (about the variational approach for the analysis of general equilibrium models see for example [9] and [10]). The analysis presented in this paper indicates that the variational inequality approach promises to be applicable in many specifications of the incomplete market model. 相似文献
74.
Rombouts Y Elass E Biot C Maes E Coddeville B Burguière A Tokarski C Buisine E Trivelli X Kremer L Guérardel Y 《Journal of the American Chemical Society》2010,132(45):16073-16084
Although lipo-oligosaccharides (LOSs) are recognized as major parietal components in many mycobacterial species, their involvement in the host-pathogen interactions have been scarcely documented. In particular, the biological implications arising from the high degree of structural species-specificity of these glycolipids remain largely unknown. Growing recognition of the Mycobacterium marinum-Danio rerio as a specific host-pathogen model devoted to the study of the physiopathology of mycobacterial infections prompted us to elucidate the structure-to-function relationships of the elusive end-product, LOS-IV, of the LOS biosynthetic pathway in M. marinum. Combination of physicochemical and molecular modeling methods established that LOS-IV resulted from the differential transfer on the caryophyllose-containing LOS-III of a family of very unusual N-acylated monosaccharides, naturally present as different diastereoisomers. In agreement with the partial loss of pathogenecity previously reported in a LOS-IV-deficient M. marinum mutant, we demonstrated that this terminal monosaccharide conferred to LOS-IV important biological functions, including macrophage activating properties. 相似文献
75.
A concise and efficient asymmetric synthesis of ACNO analogues of morphine is reported. 相似文献
76.
Sonia Palha Rijkje Dekker Koeno Gravemeijer Bernadette van Hout-Wolters 《The Journal of Mathematical Behavior》2013
Meaningful learning of formal mathematics in regular classrooms remains a problem in mathematics education. Research shows that instructional approaches in which students work collaboratively on tasks that are tailored to problem solving and reflection can improve students’ learning in experimental classrooms. However, these sequences involve often carefully constructed reinvention route, which do not fit the needs of teachers and students working from conventional curriculum materials. To help to narrow this gap, we developed an intervention—‘shift problem lessons’. The aim of this article is to discuss the design of shift problems and to analyze learning processes occurring when students are working on the tasks. Specifically, we discuss three paradigmatic episodes based on data from a teaching experiment in geometrical proof. The episodes show that is possible to create a micro-learning ecology where regular students are seriously involved in mathematical discussions, ground their mathematical understanding and strengthen their relational framework. 相似文献
77.
The paper deals with the asymptotic formulation and justification of a mechanical model for a dynamic piezoelastic shallow shell in Cartesian coordinates. Starting from the three‐dimensional dynamic piezoelastic problem and by an asymptotic approach, the authors study the convergence of the displacement field and of the electric potential as the thickness of the shell goes to zero. In order to obtain a nontrivial limit problem by asymptotic analysis, we need different scalings on the mass density. The authors show that the transverse mechanical displacement field coupled with the in‐plane components solves an problem with new piezoelectric characteristics and also investigate the very popular case of cubic crystals and show that, for two‐dimensional shallow shells, the coupling piezoelectric effect disappears. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
78.
Dr. Lubna Ghani Dr. Seonghoon Kim Dr. Haoqing Wang Hyun Sung Lee Dr. Jonas S. Mortensen Dr. Satoshi Katsube Dr. Yang Du Dr. Aiman Sadaf Dr. Waqar Ahmed Prof. Bernadette Byrne Prof. Lan Guan Prof. Claus J. Loland Prof. Brian K. Kobilka Prof. Wonpil Im Prof. Pil Seok Chae 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(21):e202200116
Membrane proteins are of biological and pharmaceutical significance. However, their structural study is extremely challenging mainly due to the fact that only a small number of chemical tools are suitable for stabilizing membrane proteins in solution. Detergents are widely used in membrane protein study, but conventional detergents are generally poor at stabilizing challenging membrane proteins such as G protein-coupled receptors and protein complexes. In the current study, we prepared tandem triazine-based maltosides (TZMs) with two amphiphilic triazine units connected by different diamine linkers, hydrazine (TZM−Hs) and 1,2-ethylenediamine (TZM−Es). These TZMs were consistently superior to a gold standard detergent (DDM) in terms of stabilizing a few membrane proteins. In addition, the TZM−Es containing a long linker showed more general protein stabilization efficacy with multiple membrane proteins than the TZM−Hs containing a short linker. This result indicates that introduction of the flexible1,2-ethylenediamine linker between two rigid triazine rings enables the TZM−Es to fold into favourable conformations in order to promote membrane protein stability. The novel concept of detergent foldability introduced in the current study has potential in rational detergent design and membrane protein applications. 相似文献
79.
Robson Matos Mohamed F. Meidine John F. Nixon Bernadette F. Trigo Passos Edgar Niecke Detlef Barion 《Journal of organometallic chemistry》1990,390(3)
Different types of ligating behaviour of the R
R′ ring system are reported; the sp2 hybridised phosphorus is the donor atom in Pt(0), W(0) and Rh(I) complexes, whereas ligation of the sp3 hybridised phosphorus atom is preferred by Pd(II), and both phosphorus atoms are ligated in dinuclear Pt(II) systems. 相似文献
80.
Baldridge KK Donovan-Merkert BT O'Connor JM Lee LI Closson A Fandrick D Tran T Bunker KD Fouzi M Gantzel P 《Organic & biomolecular chemistry》2003,1(5):763-766
The metal-enediyne complexes [(eta 5-C5H5)Fe[eta 5-1,2-C5H3C identical to C(CH2)nC identical to]] (4, n = 4; 5, n = 5) and [(eta 5-C5H5)-Fe[eta 5-1,2-C5H3(C identical to C Me)2]] (6) were prepared from 1,2-diethynylferrocene (3). Complexes 4 and 5 were characterized in the solid state by X-ray crystallographic analysis. The structures of 4 and 6 were determined by computation using ab initio methods. A correlation was observed between ring-strain and increased ease of electrochemical oxidation along the series 6 (+0.164 V) to 5(+0.152 V) to 4 (+0.123 V). A similar trend in ionization potentials was identified in both the gas phase and in solution by computational methods. 相似文献