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1.
Kuan Wang Haoxiang Zhuo Jiantao Wang Fanny Poon Xueliang Sun Biwei Xiao 《Advanced functional materials》2023,33(13):2212607
Branded with low cost and a high degree of safety, with an ambitious aim of substituting lithium-ion batteries in many fields, sodium-ion batteries have received fervid attention in recent years after being dormant for decades. Layered materials are a major focus of study owing to the extensive experience already gained in lithium-ion batteries, and the pursuit of a Mn-rich composition is critical to reduce the cost while retaining the performance. This review provides a timely update of the recent progress of Mn-rich layered materials for sodium-ion batteries based on the understandings of the phase forming principles, structure transformation upon cycling and charge compensation mechanisms and discusses potential ambiguities in the pursuit of high-performance materials. 相似文献
2.
Thermal silazane cleavage of dichloroboryldisilylamines (SiClmMe3?m)N(SiMe3)(BCl2) (1: m = 1; 2: m = 2) at 196 °C leads to the borazine derivates [(SiClmMe3?m)NB(ClnMe1?n)]3 (3: m = 1, n = 0.185; 4: m = 2, n = 0.111) characterized by NMR and IR spectroscopy and mass spectrometry. Single‐crystal X‐ray diffraction structure analyses reveal (BN)3 units with unusual twisted boat conformations in both compounds. Additionally, more detailed studies are done to clear up the function of the by‐products (SiClmMe3?m)N(SiClMe2)(BClMe) formed during the cyclization step leading to asymmetrically boron substituted borazine derivatives. The single‐source precursors 3 and 4 were cross‐linked with methylamine producing polymers 3P and 4P, which were transformed into black amorphous materials with ceramic yields of 20.8 % and 50.3 %, respectively. Ceramic 4C (Si1.00B0.98 N2.55 C1.37O0.05) was further investigated by 11B and 29Si magic angle spinning (MAS) NMR spectroscopy. A combined study of high‐temperature TG analyses and X‐ray powder diffraction analyses confirms the thermal stability of 4C up to 1670 °C. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
3.
Fanny Danton Dr. Mohamed Othman Dr. Ata Martin Lawson Dr. Ján Moncol Dr. Alina Ghinet Prof. Benoît Rigo Prof. Adam Daïch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(24):6113-6118
An efficient domino transformation using a phenyliodine(III) diacetate (PIDA)/I2 combination towards Morin 1,4-thiazine compounds has been developed starting from N,S-acetals. The latter leads to “one-step” regioselective methylene insertion without the need for traditional sulfoxide intermediates in good yields. The reaction involves easily accessible N,S-acetals obtained from cost-effective basic ketones and cysteamine as starting materials. This process ultimately leads to 1,4-thiazines related to natural product and fused derivatives necessary for further QSAR study. 相似文献
4.
Menel Ben Frej Fanny d'Orlyé Gerson F. Duarte-Junior Wendell K. T. Coltro Anne Varenne 《Electrophoresis》2022,43(20):2044-2048
A low-cost and straightforward hybrid NOA (Norland optical adhesive) 81-glass microchip electrophoresis device was designed and developed for protein separation using indirect fluorescence detection. This new microchip was first characterized in terms of surface charge density via electroosmotic mobility measurement and stability over time. A systematic determination of the electroosmotic mobility (μeo) over a wide pH range (2–10) and at various ionic strengths (20–50 mM) was developed for the first time via the neutral marker approach in an original simple frontal methodology. The evolution of μeo was proved consistent with the silanol and thiol functions arising from the glass and the NOA materials, respectively. The repeatability and reproducibility of the measurements on different microchips (RSD < 14%) and within 15 days (less than 5% decrease) were successfully demonstrated. The microchip was then applied for the efficient electrophoretic separation of proteins in a zonal mode coupled with indirect fluorescence detection, which is, to our knowledge, the first proof of concept of capillary zone electrophoresis in this hybrid microsystem. 相似文献
5.
Rami Khazaka Etienne Moulin Mathieu Boccard Loïc Garcia Simon Hnni Franz‐Josef Haug Fanny Meillaud Christophe Ballif 《Progress in Photovoltaics: Research and Applications》2015,23(9):1182-1189
We compare the performance of two back reflector designs on the optoelectrical properties of microcrystalline silicon solar cells. The first one consists of a 5‐µm‐thick low‐pressure chemical vapor deposition (LPCVD)‐ZnO electrode combined with a white sheet; the second one incorporates an Ag reflector deposited on a thin LPCVD‐ZnO layer (with thickness below 200 nm). For this latter design, the optical loss in the nano‐rough Ag reflector can be strongly reduced by smoothing the surface of the thin underlying ZnO layer, by means of an Ar‐plasma treatment. Because of its superior lateral conductivity, the thin‐ZnO/Ag back reflector design provides a higher fill factor than the dielectric back reflector design. When decreasing the roughness of the front electrode with respect to our standard front LPCVD‐ZnO layer, the electrical cell performance is improved; in addition, the implementation of the thin‐ZnO/Ag back reflector leads to a significant relative gain in light trapping. Applying this newly optimized combination of front and back electrodes, the conversion efficiency is improved from 8.9% up to 9.4%, for cells with an active‐layer thickness of only 1.1 µm. We thereby highlight the necessity to optimize simultaneously the front and back electrodes. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
6.
We study the limiting behavior of a singularly perturbed Schr?dinger-Poisson system describing a 3-dimensional electron gas
strongly confined in the vicinity of a plane (x, y) and subject to a strong uniform magnetic field in the plane of the gas. The coupled effects of the confinement and of the
magnetic field induce fast oscillations in time that need to be averaged out. We obtain at the limit a system of 2-dimensional
Schr?dinger equations in the plane (x, y), coupled through an effective selfconsistent electrical potential. In the direction perpendicular to the magnetic field,
the electron mass is modified by the field, as the result of an averaging of the cyclotron motion. The main tools of the analysis
are the adaptation of the second order long-time averaging theory of ODEs to our PDEs context, and the use of a Sobolev scale
adapted to the confinement operator. 相似文献
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Borohydride complexes of the rare earths have attracted increasing interest during the last decade. This review aims to cover recent results over this period with respect to the preparation, characterization, structure, and applications in organic chemistry of this family of compounds, including inorganic and organometallic complexes. Special emphasis is made on their use for polymerization catalysis. 相似文献