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81.
82.
Dr. James Biggs Dr. Karsten Danielmeier Dr. Julia Hitzbleck Dr. Jens Krause Tom Kridl Dr. Stephan Nowak Dr. Enrico Orselli Dr. Xina Quan Dirk Schapeler Will Sutherland Dr. Joachim Wagner 《Angewandte Chemie (International ed. in English)》2013,52(36):9409-9421
We present the development and applications of dielectric elastomers. For the last 10 years the significance of this class of polymers has risen as more applications seem possible and first products have been commercialized. 相似文献
83.
We consider two final-offer arbitration procedures in the case where there is more than one arbitrator. Two players, labeled 1 and 2 and interpreted here as Labor and Management, respectively, are in dispute about an increase in the wage rate. They submit final offers to a Referee. There are N arbitrators. Each of the arbitrators has her own assessment and selects the offer which is closest to her assessment. After that each arbitrator informs the Referee about her decision. The Referee counts the votes and declares the player obtaining the most votes to be the winner. Under the second arbitration scheme, the Referee takes into account only the assessments which lie between the players’ offers. The game is modeled as a zero-sum game. The Nash equilibrium in this arbitration game is derived. 相似文献
84.
Jinkyung Jung Colin Denniston Enzo Orlandini Julia M. Yeomans Corresponding author 《Liquid crystals》2013,40(12):1455-1462
We have studied domain growth in nematic liquid crystals using a lattice Boltzmann algorithm to solve the full, three-dimensional equations of hydrodynamics. An initially cylindrical V (bend) domain in an H (splay) state grows or shrinks anisotropically in agreement with experiment. A disclination loop forms at the mid-point of the wall surrounding the domain. We argue that different director configurations at different points on the loop lead to velocity anisotropy and show that both elastic effects and backflow are relevant. We discuss the dependence of the domain wall velocity on surface tilt and on the magnitude of an applied electric field. 相似文献
85.
Jorge L. Flores Gastón A. Ayubi Julia R. Alonso Ariel Fernández J. Matías Di Martino José A. Ferrari 《Optik》2013
We present a hybrid method for segmentation of intensity images, which combines an optical contouring technique and digital algorithms for linking edge points or image segmentation. In a first stage, the digital image to be processed is displayed in a twisted-nematic liquid-crystal display (LCD), which is placed between a polarizer–analyzer pair at 45 deg (instead of 90 deg as occurs in standard LCDs). It is not difficult to demonstrate that the proposed setup produces a resultant image with very pronounced dark contours at middle intensity. After the optical preprocessing, two different digital algorithms are applied: an edge linking algorithm (modified chain code) and a simple thresholding technique for image segmentation. The proposed procedure works well with monochromatic and color images. The method could be useful as a robust technique for segmentation of large images in real-time, which presents potential applications in medical and biological imaging. 相似文献
86.
Julia Ertl Dr. Maria Elena Ortiz-Soto Thien Anh Le Julian Bechold Junwen Shan Dr. Jörg Teßmar Prof. Bernd Engels Prof. Jürgen Seibel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(26):6533-6541
Selective chemical modification of proteins plays a pivotal role for the rational design of enzymes with novel and specific functionalities. In this study, a strategic combination of genetic and chemical engineering paves the way for systematic construction of biocatalysts by tuning the product spectrum of a levansucrase from Bacillus megaterium (Bm-LS), which typically produces small levan-like oligosaccharides. The implementation of site-directed mutagenesis followed by a tyrosine-specific modification enabled control of the product synthesis: depending on the position, the modification provoked either enrichment of short oligosaccharides (up to 800 % in some cases) or triggered the formation of high molecular weight polymer. The chemical modification can recover polymerization ability in variants with defective oligosaccharide binding motifs. Molecular dynamic (MD) simulations provided insights into the effect of modifying non-native tyrosine residues on product specificity. 相似文献
87.
Dr. Julia Stroh Torvid Feiler Dr. Naveed Zafar Ali Prof. Manuel E. Minas da Piedade Dr. Franziska Emmerling 《ChemistryOpen》2019,8(7):1012-1019
Mechanochemistry offers an environmentally benign and facile synthesis method for a variety of cement paste constituents. In addition, these methods can be used to selectively tune the properties of cement components. The mineral ettringite is an important component of cementitious materials and has additional technological potential due to its ion exchange properties. Synthesis of ettringite via mechanochemistry is an environmentally friendly alternative to conventional wet-chemical synthesis established in industry. This contribution explores the mechanism of a two-step mechanochemical synthesis of ettringite, which was previously found to greatly improve the reaction conversion as compared with one-pot synthesis. The crystallinity of Al(OH)3 was found to decrease during the first stage of this mechanochemical synthesis. This was correlated to a significant decrease in the particle size of Al(OH)3 in this stage. No other significant changes were found for the other components, suggesting that mechanochemical activation of Al(OH)3 is responsible for the enhanced formation of ettringite by the two-step approach. The environmentally friendly approach developed for ettringite synthesis offers a versatile synthetic strategy, which can be applied to synthesise further cementitious materials. 相似文献
88.
Julia Vallejo Alejandro Pascual‐Álvarez Dr. Joan Cano Dr. Isabel Castro Prof. Dr. Miguel Julve Prof. Dr. Francesc Lloret Dr. J. Krzystek Prof. Dr. Giovanni De Munno Dr. Donatella Armentano Prof. Dr. Wolfgang Wernsdorfer Dr. Rafael Ruiz‐García Dr. Emilio Pardo 《Angewandte Chemie (International ed. in English)》2013,52(52):14075-14079
89.
Agnieszka Wojciechowska Agnieszka Szuster-Ciesielska Monika Sztandera Romualda Bregier-Jarzębowska Anna Jarząb Tomasz Rojek Urszula K. Komarnicka Agnieszka Bojarska-Junak Julia Jezierska 《应用有机金属化学》2020,34(8):e5698
A search for new drugs that overcome the multidrug resistance of microorganisms or are effective against cancer cells prompted us to investigate the binary and ternary Cu(II) complexes containing L-arginine, [CuCl(L-Arg)(phen)]Cl·2H2O (phen = 1,10-phenanthroline) ( 1 ) and [Cu(L-Arg)2(H2O)]C2O4·6H2O ( 2 ), for which crystal and molecular structures were characterized previously. In order to discuss the biological function, the complexes have been screened for their antitumor activity against A549 (human lung cancer cells), HepG2 (human liver hepatocellular carcinoma cells) and antimicrobial activity. To identify the complexes forms existing in the solutions of 1 and 2 crystals, the results obtained from EPR, NIR–Vis–UV and MS (mass spectrometry) measurements were correlated with those from analysis of potentiometric titration of Cu(II)―L-Arg and Cu(II)―L-Arg―phen systems. This comprehensive study indicated that the [Cu(L-Arg)(phen)]2+ and [Cu(L-Arg)2]2+ species are dominant in the solution. Complexes 1 and 2 were found to present specific ligand-dependent cytotoxic and antiproliferative potential against cancer cells. They also show antibacterial activity against Gram-positive and Gram-negative bacteria as well as display antifungal properties. 相似文献
90.
Julia Calatayud Juan Carlos Corts Marc Jornet 《Mathematical Methods in the Applied Sciences》2019,42(18):7259-7267
In this paper, we address the problem of approximating the probability density function of the following random logistic differential equation: P′(t,ω)=A(t,ω)(1?P(t,ω))P(t,ω), t∈[t0,T], P(t0,ω)=P0(ω), where ω is any outcome in the sample space Ω. In the recent contribution [Cortés, JC, et al. Commun Nonlinear Sci Numer Simulat 2019; 72: 121–138], the authors imposed conditions on the diffusion coefficient A(t) and on the initial condition P0 to approximate the density function f1(p,t) of P(t): A(t) is expressed as a Karhunen–Loève expansion with absolutely continuous random coefficients that have certain growth and are independent of the absolutely continuous random variable P0, and the density of P0, , is Lipschitz on (0,1). In this article, we tackle the problem in a different manner, by using probability tools that allow the hypotheses to be less restrictive. We only suppose that A(t) is expanded on L2([t0,T]×Ω), so that we include other expansions such as random power series. We only require absolute continuity for P0, so that A(t) may be discrete or singular, due to a modified version of the random variable transformation technique. For , only almost everywhere continuity and boundedness on (0,1) are needed. We construct an approximating sequence of density functions in terms of expectations that tends to f1(p,t) pointwise. Numerical examples illustrate our theoretical results. 相似文献