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201.
202.
Le Gouët J Morvan L Alouini M Bourderionnet J Dolfi D Huignard JP 《Optics letters》2007,32(9):1090-1092
We demonstrate the generation of optically carried, broadly tunable, millimeter-wave signals with a dual-frequency single-axis Nd:YAG laser. A frequency difference as high as 127 GHz is reached thanks to an intracavity electro-optically tunable etalon made of lead zirconate tantalate (PLZT) ceramic. We show that the available frequency range is actually limited by the bandwidth of the amplification medium, namely, far beyond the usually accepted free spectral range value in the case of a single-axis laser. Both coarse discrete and fine continuous tunabilities are obtained with the same voltage-controlled device, opening the way to widely tunable low-phase-noise optically carried submillimeter or even terahertz sources. 相似文献
203.
Nikola Popović Dirk Praetorius Anja Schlömerkemper 《Continuum Mechanics and Thermodynamics》2007,19(1-2):67-80
The mathematical and physical analysis of magnetoelastic phenomena is a topic of ongoing research. Different formulae have
been proposed to describe the magnetic forces in macroscopic systems. We discuss several of these formulae in the context
of rigid magnetized bodies. In case the bodies are in contact, we consider formulae both in the framework of macroscopic electrodynamics
and via a multiscale approach, i.e., in a discrete setting of magnetic dipole moments. We give mathematically rigorous proofs
for domains of polygonal shape (as well as for more general geometries) in two and three space dimensions. In an accompanying
second article, we investigate the formulae in a number of numerical experiments, where we focus on the dependence of the
magnetic force on the distance between the bodies and on the case when the two bodies are in contact. The aim of the analysis
as well as of the numerical simulation is to contribute to the ongoing debate about which formula describes the magnetic force
between macroscopic bodies best and to stimulate corresponding real-life experiments.
相似文献
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205.
Sawitree Saengkaew Tawatchai Charinpanitkul Hathaichanok Vanisri Wiwut Tanthapanichakoon Yves Biscos Nicolas Garcia Gérard Lavergne Loïc Mees Gérard Gouesbet Gérard Grehan 《Experiments in fluids》2007,43(4):595-601
The rainbow refractrometry, under its different configurations (classical and global), is an attractive technique to extract
information from droplets in evaporation such as diameter and temperature. Recently a new processing strategy has been developed
which increases dramatically the size and refractive index measurements accuracy for homogeneous droplets. Nevertheless, for
mono component as well as for multicomponent droplets, the presence of temperature and/or of concentration gradients induce
the presence of a gradient of refractive index which affects the interpretation of the recorded signals. In this publication,
the effect of radial gradient on rainbow measurements with a high accuracy never reached previously is quantified. 相似文献
206.
Pickering Interfacial Catalysis for Biphasic Systems: From Emulsion Design to Green Reactions 下载免费PDF全文
Dr. Marc Pera‐Titus Dr. Loïc Leclercq Dr. Jean‐Marc Clacens Dr. Floryan De Campo Prof. Dr. Véronique Nardello‐Rataj 《Angewandte Chemie (International ed. in English)》2015,54(7):2006-2021
Pickering emulsions are surfactant‐free dispersions of two immiscible fluids that are kinetically stabilized by colloidal particles. For ecological reasons, these systems have undergone a resurgence of interest to mitigate the use of synthetic surfactants and solvents. Moreover, the use of colloidal particles as stabilizers provides emulsions with original properties compared to surfactant‐stabilized emulsions, microemulsions, and micellar systems. Despite these specific advantages, the application of Pickering emulsions to catalysis has been rarely explored. This Minireview describes very recent examples of hybrid and composite amphiphilic materials for the design of interfacial catalysts in Pickering emulsions with special emphasis on their assets and challenges for industrially relevant biphasic reactions in fine chemistry, biofuel upgrading, and depollution. 相似文献
207.
208.
Dr. Oriol Penon Tania Patiño Prof. Lleonard Barrios Prof. Carme Nogués Prof. David B. Amabilino Prof. Klaus Wurst Prof. Lluïsa Pérez-García 《ChemistryOpen》2015,4(2):127-136
A potential new photosensitizer based on a dissymmetric porphyrin derivative bearing a thiol group was synthesized. 5-[4-(11-Mercaptoundecyloxy)-phenyl-10,15,20-triphenylporphyrin (PR-SH) was used to functionalize gold nanoparticles in order to obtain a potential drug delivery system. Water-soluble multifunctional gold nanoparticles GNP-PR/PEG were prepared using the Brust–Schiffrin methodology, by immobilization of both a thiolated polyethylene glycol (PEG) and the porphyrin thiol compound (PR-SH). The nanoparticles were fully characterized by transmission electron microscopy and 1H nuclear magnetic resonance spectroscopy, UV/Vis absorption spectroscopy, and X-ray photoelectron spectroscopy. Furthermore, the ability of GNP-PR/PEGs to induce singlet oxygen production was analyzed to demonstrate the activity of the photosensitizer. Cytotoxicity experiments showed the nanoparticles are nontoxic. Finally, cellular uptake experiments demonstrated that the functionalized gold nanoparticles are internalized. Therefore, this colloid can be considered to be a novel nanosystem that could potentially be suitable as an intracellular drug delivery system of photosensitizers for photodynamic therapy. 相似文献
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Dr. Georgian Melinte Dr. Veselina Georgieva Dr. Marie‐Anne Springuel‐Huet Dr. Andreï Nossov Prof. Ovidiu Ersen Dr. Flavien Guenneau Prof. Antoine Gedeon Dr. Ana Palčić Dr. Krassimir N. Bozhilov Dr. Cuong Pham‐Huu Prof. Shilun Qiu Dr. Svetlana Mintova Dr. Valentin Valtchev 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(50):18316-18327
The principle aspects and constraints of the dynamics and kinetics of zeolite nucleation in hydrogel systems are analyzed on the basis of a model Na‐rich aluminosilicate system. A detailed time‐series EMT‐type zeolite crystallization study in the model hydrogel system was performed to elucidate the topological and temporal aspects of zeolite nucleation. A comprehensive set of analytical tools and methods was employed to analyze the gel evolution and complement the primary methods of transmission electron microscopy (TEM) and nuclear magnetic resonance (NMR) spectroscopy. TEM tomography reveals that the initial gel particles exhibit a core–shell structure. Zeolite nucleation is topologically limited to this shell structure and the kinetics of nucleation is controlled by the shell integrity. The induction period extends to the moment when the shell is consumed and the bulk solution can react with the core of the gel particles. These new findings, in particular the importance of the gel particle shell in zeolite nucleation, can be used to control the growth process and properties of zeolites formed in hydrogels. 相似文献