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541.
In this article, we present a new family of chipless tags, which permit encoding of digital data in the terahertz domain. These devices consist of stacked dielectric media whose thicknesses are of the same order as terahertz wavelengths. Since the information is encoded in the volume of these multilayer terahertz tags, they can easily be associated with classical identification techniques (e.g., barcode, radio frequency identification), where information is encoded at the surface of the tag, to provide higher data security. The principle of this encoding approach is studied and experimentally demonstrated in this paper. A 2 bit tag prototype has been realized and measured for validation purposes. 相似文献
542.
543.
Frederic?LachaudEmail author Christine?Espinosa Laurent?Michel Pierre?Rahme Robert?Piquet 《Applied Composite Materials》2015,22(4):377-403
The composite materials are nowadays widely used in aeronautical domain. These materials are subjected to different types of loading that can damage a part of the structure. This diminishes the resistance of the structure to failure. In this paper, matrix cracking and delamination propagation in composite laminates are simulated as a part of damage. Two different computational strategies are developed: (i) a cohesive model (CM) based on the classical continuum mechanics and (ii) a continuous damage material model (CDM) coupling failure modes and damage. Another mixed methodology (MM) is proposed using the continuous damage model for delamination initiation and the cohesive model for 3D crack propagation and mesh openings. A good agreement was obtained when compared simple characterization tests and corresponding simulations. 相似文献
544.
The surface wettability, such as superhydrophobic properties, of nanofibrous structures is highly depending on their size, length, spacing or orientation to the surface. Finding a way to control all these characteristics is extremely important in a theoretical point of view and for various applications. Here, we report the possible tuning of all these characteristics by adjusting the length (n) of the alkyl chains of electrodeposited poly(3,3‐dialkyl‐3,4‐propylenedioxythiophene), which allows the formation of horizontally or vertically oriented nanofibers of various dimensions and spacings. Here, we play especially on the hydrophilic/hydrophobic characteristics of the polymer to change the growth of a polymer on a substrate and the distance between the polymer backbones. For example, a change in the fiber orientation from horizontal to vertical is observed for n = 2. For n < 2, the polymer fibers are mainly horizontally aligned while for n > 2, the polymer fibers are vertically aligned. 相似文献
545.
Frederic Aguesse Juan Miguel Lpez del Amo Vladimir Roddatis Ainara Aguadero John A. Kilner 《Advanced Materials Interfaces》2014,1(7)
The grain boundary resistivity problem of highly conductive bulk Li0.34La0.55TiO3 perovskite has been investigated by means of impedance spectroscopy and solid‐state NMR of samples processed in controlled atmospheres. The samples were sintered in air, synthetic air, and oxygen, in which the level of moisture varied. A dry atmosphere is critical to obtain dense ceramics with a low grain boundary resistivity. The grain boundary conductivity is five times higher for samples sintered in oxygen atmosphere due to the suppression of Li2CO3 secondary phase formation, which is responsible for low lithium ion diffusion at the grain boundary. 相似文献
546.
Friederike I. Nollmann Antje K. Heinrich Alexander O. Brachmann Christophe Morisseau Krishnendu Mukherjee Ángel M. Casanova‐Torres Frederic Strobl David Kleinhans Sebastian Kinski Katharina Schultz Michael L. Beeton Marcel Kaiser Ya‐Yun Chu Long Phan Ke Aunchalee Thanwisai Kenan A. J. Bozhüyük Narisara Chantratita Prof. Dr. Friedrich Götz Prof. Nick R. Waterfield Prof. Dr. Andreas Vilcinskas Prof. Dr. Ernst H. K. Stelzer Prof. Dr. Heidi Goodrich‐Blair Prof. Dr. Bruce D. Hammock Prof. Dr. Helge B. Bode 《Chembiochem : a European journal of chemical biology》2015,16(5):766-771
Simple urea compounds (“phurealipids”) have been identified from the entomopathogenic bacterium Photorhabdus luminescens, and their biosynthesis was elucidated. Very similar analogues of these compounds have been previously developed as inhibitors of juvenile hormone epoxide hydrolase (JHEH), a key enzyme in insect development and growth. Phurealipids also inhibit JHEH, and therefore phurealipids might contribute to bacterial virulence. 相似文献
547.
Patrick Gilles Guillaume Cohen Frederic Monies Walter Rubio 《The International Journal of Advanced Manufacturing Technology》2014,72(9-12):1377-1387
Several solutions can be considered to resolve the problem of positioning a cutting tool on a free-form surface when five-axis milling. To choose a unique solution, in addition to the cutter–workpiece contact, an additional criterion can be taken into account. This may concern the local geometry of the surface or yet again the width milled to maximise the metal removal rate, but technological criteria relating to the cutting phenomenon and the quality of the surface produced are not considered. The present article introduces a strategy applying positioning combined with balancing of the transversal cutting force. This method involves using the ploughing effect of the milling cutters by simultaneously engaging the teeth located to the front of the cutter in relation to the feed movement and also those to the rear. The positioning obtained stabilises the cutter and contributes to making a net improvement in its dynamic behaviour. This leads in turn to significantly higher quality of the milled surface. The article presents a method to apply balancing of the transversal cutting force to two types of machining passes and elaborates an associated strategy to plan cutter paths enabling an improvement in surface quality to be achieved. 相似文献
548.
Nikolai A. Löhr Maximilian C. Urban Frederic Eisen Lukas Platz Dr. Wolfgang Hüttel Dr. Markus Gressler Prof. Dr. Michael Müller Prof. Dr. Dirk Hoffmeister 《Chembiochem : a European journal of chemical biology》2023,24(3):e202200649
The nonreducing iterative type I polyketide synthases (NR-PKSs) CoPKS1 and CoPKS4 of the webcap mushroom Cortinarius odorifer share 88 % identical amino acids. CoPKS1 almost exclusively produces a tricyclic octaketide product, atrochrysone carboxylic acid, whereas CoPKS4 shows simultaneous hepta- and octaketide synthase activity and also produces the bicyclic heptaketide 6-hydroxymusizin. To identify the region(s) controlling chain length, four chimeric enzyme variants were constructed and assayed for activity in Aspergillus niger as heterologous expression platform. We provide evidence that the β-ketoacyl synthase (KS) domain determines chain length in these mushroom NR-PKSs, even though their KS domains differ in only ten amino acids. A unique proline-rich linker connecting the acyl carrier protein with the thioesterase domain varies most between these two enzymes but is not involved in chain length control. 相似文献
549.
Alexandru Sava Frederic Buron Sylvain Routier Alina Panainte Nela Bibire Sandra Mdlina Constantin Florentina Geanina Lupacu Alin Viorel Foca Lenua Profire 《International journal of molecular sciences》2021,22(13)
Starting from indomethacin (IND), one of the most prescribed non-steroidal anti-inflammatory drugs (NSAIDs), new nitric oxide-releasing indomethacin derivatives with 1,3,4-oxadiazole-2-thiol scaffold (NO-IND-OXDs, 8a–p) have been developed as a safer and more efficient multitarget therapeutic strategy. The successful synthesis of designed compounds (intermediaries and finals) was proved by complete spectroscopic analyses. In order to study the in silico interaction of NO-IND-OXDs with cyclooxygenase isoenzymes, a molecular docking study, using AutoDock 4.2.6 software, was performed. Moreover, their biological characterization, based on in vitro assays, in terms of thermal denaturation of serum proteins, antioxidant effects and the NO releasing capacity, was also performed. Based on docking results, 8k, 8l and 8m proved to be the best interaction for the COX-2 (cyclooxygense-2) target site, with an improved docking score compared with celecoxib. Referring to the thermal denaturation of serum proteins and antioxidant effects, all the tested compounds were more active than IND and aspirin, used as references. In addition, the compounds 8c, 8h, 8i, 8m, 8n and 8o showed increased capacity to release NO, which means they are safer in terms of gastrointestinal side effects. 相似文献
550.
Caroline Supplis Fabrice Gros Ghiles Dahi Jérémi Dauchet Matthieu Roudet Frederic Gloaguen Jean-François Cornet 《International Journal of Hydrogen Energy》2018,43(17):8221-8231
The iron–thiolate complex [Fe2(μ-bdt)CO6] (bdt = 1,2-benzenedithiolate) is a simplified model of the active site of diiron hydrogenase enzymes. Here, we describe the implementation of this noble-metal-free catalyst in aqueous solutions using eosin Y as photosensitizer and triethylamine as an electron donor in an experimental bench specially designed for the study of H2 photoproduction. The bench is composed of an adjustable visible light source, a fully equipped flat torus photoreactor and analytical devices. Rates of H2 production under varied experimental conditions were obtained from an accurate measurement of pressure increase. A spectral radiative analysis involving blue photons of the source primarily absorbed has been carried out. Results have proven the rate of H2 production is proportional to the mean volumetric rate of radiant light absorbed demonstrating a linear thermokinetic coupling. The bio-inspired catalyst has proven non-limiting and reveals interesting capabilities for future large scale H2 production. 相似文献