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排序方式: 共有478条查询结果,搜索用时 15 毫秒
31.
Dr. Anil Reddy Marri Edoardo Marchini Dr. Valentin Diez Cabanes Dr. Roberto Argazzi Dr. Mariachiara Pastore Prof. Stefano Caramori Prof. Carlo Alberto Bignozzi Dr. Philippe C. Gros 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(65):16260-16269
A series of six new Fe(II)NHC-carboxylic sensitizers with their ancillary ligand decorated with functions of varied electronic properties have been designed with the aim to increase the metal-to- surface charge separation and light harvesting in iron-based dye-sensitized solar cells (DSSCs). ARM130 scored the highest efficiency ever reported for an iron-sensitized solar cell (1.83 %) using Mg2+ and NBu4I-based electrolyte and a thick 20 μm TiO2 anode. Computational modelling, transient absorption spectroscopy and electrochemical impedance spectroscopy (EIS) revealed that the electronic properties induced by the dimethoxyphenyl-substituted NHC ligand of ARM130 led to the best combination of electron injection yield and spectral sensitivity breadth. 相似文献
32.
Guilherme D. VilelaRafaela R. da Rosa Paulo H. SchneiderIvan H. Bechtold Juliana EccherAloir A. Merlo 《Tetrahedron letters》2011,52(49):6569-6572
A collection of isoxazoles derivatives has been efficiently synthesized in three steps. The oximation reaction of aldehydes followed by nitrile oxide [3+2] 1,3-dipolar cycloaddition and MnO2-oxidation reaction furnished the title compounds which were purified by simple filtration on celite®. 相似文献
33.
34.
Valerio Annovazzi-Lodi Giuseppe Aromataris Mauro Benedetti Michael Hamacher Sabina Merlo Valeria Vercesi 《Optical and Quantum Electronics》2010,42(3):143-156
In this paper, we numerically evaluate private data transmission using a three-laser scheme, consisting of a pair of twin
semiconductor lasers, driven to chaos by delayed optical feedback in a short cavity, and optically injected by a third chaotic
laser which forces them to synchronize. This laser is selected with different internal parameters with respect to the twin
pair, so that the emissions of the synchronized, matched lasers, are highly correlated, whereas their correlation with the
driver is low. The digital message modulates the emission of the transmitter, as in a standard Chaos Modulation scheme. Message
recovery is then obtained by subtracting, from the transmitted chaos-masked message, the chaos, locally generated by the synchronized
receiver laser. Simulations have been performed with the Lang-Kobayashi model, and, in view of application to private transmission,
we have investigated the effect of the parameter mismatch, between transmitter and receiver, on message recovery. A preliminary
experimental evaluation has been also performed using specially designed InP integrated modules. 相似文献
35.
Optical feedback modifies the power vs. current diagram of a laser diode as well as its spectrum. Though optimization of the spectral characteristics is usually the main goal in the design of an external cavity source, power efficiency is also important, especially with relatively high power devices, where temperature variations due to dissipation can have an impact on the wavelength stability and on the laser lifetime. A useful parameter to describe the total power efficiency of the stabilized laser, relative to that of the solitary laser, is proposed in this paper. The dependence of this parameter on the characteristics of the active device, and of the external cavity, is investigated. 相似文献
36.
37.
Cristina Airoldi Dr. Silvia Sommaruga Dr. Silvia Merlo Paola Sperandeo Dr. Laura Cipolla Prof. Alessandra Polissi Prof. Francesco Nicotra Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(6):1897-1902
Lipopolysaccharide (LPS) is an essential component of the outer membrane of Gram‐negative bacteria and consists of three elements: lipid A, the core oligosaccharide, and the O‐antigen. The inner‐core region is highly conserved and contains at least one residue of 3‐deoxy‐D ‐manno‐octulosonate (Kdo). Arabinose‐5‐phosphate isomerase (API) is an aldo–keto isomerase catalyzing the reversible isomerization of D ‐ribulose‐5‐phosphate (Ru5P) to D ‐arabinose‐5‐phosphate (A5P), the first step of Kdo biosynthesis. By exploiting saturation transfer difference (STD) NMR spectroscopy, the structural requirements necessary for API substrate recognition and binding were identified, with the aim of designing new API inhibitors. In addition, simple experimental conditions for the STD experiments to perform a fast, robust, and efficient screening of small libraries of potential API inhibitors, allowing the identification of new potential leads, were set up. Due to the essential role of API enzymes in LPS biosynthesis and Gram‐negative bacteria survival, by exploiting these data, a new generation of potent antibacterial drugs could be developed. 相似文献
38.
Edoardo Ballico 《Designs, Codes and Cryptography》2014,73(3):1023-1026
In this note we prove that every network code over \(\mathbb{F }_q\) may be realized taking some of the osculating spaces of a smooth projective curve. 相似文献
39.
Diego Adolfo Santamaría Razo Luca Pallavidino Edoardo Garrone Francesco Geobaldo Emiliano Descrovi Angelica Chiodoni Fabrizio Giorgis 《Journal of nanoparticle research》2008,10(7):1225-1229
A sol-gel synthesis procedure based on the method proposed by Stöber et al. (J Colloid Interface Sci 26:302–315, 1968) has been adopted for the one-step preparation of mono-dispersed silica nanospheres. An excellent control of the particle diameter over a wide range is obtained by varying the amount of silicon alkoxide only, while the concentration of all other components is kept fixed: this allows the fabrication of artificial opals with a finely tuned and precisely predictable lattice parameter. 相似文献
40.
Phase noise due to thermodynamic fluctuations in the optical path length is evaluated in this paper for basic fibre interferometers. In Mach-Zehnder and Michelson interferometers, where the temperature phase fluctuation (TPF) is that intrinsic to the fibre, this noise has been reported to be comparable to shot noise and a possible limit to sensor sensitivity in practical cases. We show that in Sagnac interferometers, used in fibre gyro and in Faraday current sensors, the TPF noise is decreased with respect to that intrinsic to the fiber because propagation in the same optical path leads to a correlation of the phase fluctuations. In addition, we show that in Fabry-Perot and ring resonators, as multiple reflections increase the effective path length, TPF noise is enhanced and can be dominant over shot noise even for moderate fibre lengths. 相似文献