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131.
Nikita M. Kondratiev Valery E. Lobanov Artem E. Shitikov Ramzil R. Galiev Dmitry A. Chermoshentsev Nikita Yu. Dmitriev Andrey N. Danilin Evgeny A. Lonshakov Kirill N. Min’kov Daria M. Sokol Steevy J. Cordette Yi-Han Luo Wei Liang Junqiu Liu Igor A. Bilenko 《Frontiers of Physics》2023,18(2):21305
The stabilization and manipulation of laser frequency by means of an external cavity are nearly ubiquitously used in fundamental research and laser applications. While most of the laser light transmits through the cavity, in the presence of some back-scattered light from the cavity to the laser, the self-injection locking effect can take place, which locks the laser emission frequency to the cavity mode of similar frequency. The self-injection locking leads to dramatic reduction of laser linewidth and noise. Using this approach, a common semiconductor laser locked to an ultrahigh-Q microresonator can obtain sub-Hertz linewidth, on par with state-of-the-art fiber lasers. Therefore it paves the way to manufacture high-performance semiconductor lasers with reduced footprint and cost. Moreover, with high laser power, the optical nonlinearity of the microresonator drastically changes the laser dynamics, offering routes for simultaneous pulse and frequency comb generation in the same microresonator. Particularly, integrated photonics technology, enabling components fabricated via semiconductor CMOS process, has brought increasing and extending interest to laser manufacturing using this method. In this article, we present a comprehensive tutorial on analytical and numerical methods of laser self-injection locking, as well a review of most recent theoretical and experimental achievements. 相似文献
132.
Sergey Holovach Dr. Kostiantyn P. Melnykov Artem Skreminskiy Maksym Herasymchuk Olha Tavlui Danylo Aloshyn Dr. Petro Borysko Prof. Dr. Alexander B. Rozhenko Prof. Dr. Sergey V. Ryabukhin Prof. Dr. Dmitriy M. Volochnyuk Prof. Dr. Oleksandr O. Grygorenko 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(19):e202200331
Physico-chemical properties important to drug discovery (pKa, LogP, and aqueous solubility), as well as metabolic stability, were studied for a series of functionalized gem-difluorinated cycloalkanes and compared to those of non-fluorinated and acyclic counterparts to evaluate the impact of the fluorination. It was found that the influence of the CF2 moiety on the acidity/basicity of the corresponding carboxylic acids and amines was defined by inductive the effect of the fluorine atoms and was nearly the same for acyclic and cyclic aliphatic compounds. Lipophilicity and aqueous solubility followed more complex trends and were affected by the position of the fluorine atoms, ring size, and even the nature of the functional group present; also, significant differences were found for the acyclic and cyclic series. Also, gem-difluorination either did not affect or slightly improved the metabolic stability of the corresponding model derivatives. The presented results can be used as a guide for rational drug design employing fluorine and establish the first chapter in a catalog of the key in vitro properties of fluorinated cycloalkanes. 相似文献
133.
134.
Artem M Abakumov Marina G Rozova Evgeny V Antipov Gustaaf Van Tendeloo 《Journal of solid state chemistry》2004,177(8):2855-2861
The new Pb5Sb2MnO11 compound was synthesized using a solid-state reaction in an evacuated sealed silica tube at 650°C. The crystal structure was determined ab initio using a combination of X-ray powder diffraction, electron diffraction and high-resolution electron microscopy (a=9.0660(8)Å, b=11.489(1)Å, c=10.9426(9)Å, S.G. Cmcm, RI=0.045, RP=0.059). The Pb5Sb2MnO11 crystal structure represents a new structure type and it can be considered as quasi-one-dimensional, built up of chains running along the c-axis and consisting of alternating Mn+2O7 capped trigonal prisms and Sb2O10 pairs of edge sharing Sb+5O6 octahedra. The chains are joined together by Pb atoms located between the chains. The Pb+2 cations have virtually identical coordination environments with a clear influence of the lone electron pair occupying one vertex of the PbO5E octahedra. Electronic structure calculations and electron localization function distribution analysis were performed to define the nature of the structural peculiarities. Pb5Sb2MnO11 exhibits paramagnetic behavior down to T=5 K with Weiss constant being nearly equal to zero that implies lack of cooperative magnetic interactions. 相似文献
135.
Vladimir A. Ogurtsov Pavel V. Dorovatovskii Yan V. Zubavichus Victor N. Khrustalev Artem N. Fakhrutdinov Sergei G. Zlotin Oleg A. Rakitin 《Tetrahedron letters》2018,59(32):3143-3146
An efficient synthesis of [1,2,5]oxadiazolo[3,4-d]pyridazine 1,5,6-trioxides (1) from 3,4-bis(hydroxyimino)methyl)-1,2,5-oxadiazole 2-oxides using a mixture of concentrated nitric and trifluoroacetic acids has been developed. The scope of the unconventional reaction was established. The 4,7-dinitro[1,2,5]oxadiazolo[3,4-d]pyridazine 1,5,6-trioxide 1f represents a new high energy compound, unfortunately with low thermal stability. The parent [1,2,5]oxadiazolo[3,4-d]pyridazine 1,5,6-trioxide 1c was studied by single-crystal X-ray diffraction analysis which revealed a planar molecule with an unusually long intracyclic NN bond of 1.668(5)?Å and unexpected exo-cyclic bond angles at the nitroxyl nitrogen atoms. In the crystal, the molecules of 1c are bound to each other by strong π-π stacking and CH?O hydrogen bonding interactions into a three-dimensional framework that results in a high crystal density of 1.833?gcm?3. 相似文献
136.
We use a Flory-Huggins type approach to calculate the structure and the surface tension coefficient of the boundary between ionic and nonionic liquids. The mixture of ionic and nonionic liquids is treated as a "three-component" system including anions, cations, and neutral molecules. We show that if the affinities of the cations and the anions to the neutral molecules are different, the interface comprises an electric double layer. The presence of this layer (uncompensated electric field) stabilizes the interface: the field inhibits the ions segregation at the interface and increases the surface tension. On the other hand, the short-range volume interactions promote the segregation and decrease the surface tension. Furthermore, the surface tension coefficient can be negative, if the difference of the affinities is high enough. It implies a possibility of microphase separation of the system. 相似文献
137.
A new approach toward the synthesis of 1H-isochromenes based on the recyclization of the furan ring in the corresponding ortho-hydroxymethylbenzylfurans is described. 相似文献
138.
Shmelev N. Yu. Gongola M. I. Malysheva S. F. Belogorlova N. A. Artem’ev A. V. Fomenko Ya. S. Komarov V. Yu. Sopov K. V. Kompan’kov N. B. Sheven’ D. G. Sokolov M. N. Gushchin A. L. 《Russian Journal of Coordination Chemistry》2021,47(3):209-218
Russian Journal of Coordination Chemistry - The reaction of [Mo3S4(Tu)8(H2O)]Cl4·4H2O (Tu is thiourea) with (PhCH2CH2)2-PCH2CH2SeC5H11) (PSe) followed by purification on a chromatographic... 相似文献
139.
Lidia P. Loginova Artem U. Kulikov Elena Y. Yakovleva Alexander P. Boichenko 《Chromatographia》2008,67(7-8):615-620
Optimized conditions for the determination of 14 food preservatives were selected by using interpretative optimization strategy
and Derringer’s desirability function for combining three main chromatographic goals: resolution, separation time and ruggedness.
The best mobile phase for separation by micellar liquid chromatography contains 0.045 M SDS and 1.0% (v/v) 1-pentanol at pH 2.5 adjusted with trichloroacetic acid. The accuracy of the method was confirmed by analysis of spiked
samples and is useful for routine analysis of food preservatives in drinks due to simple sample preparation, safety and low
cost of micellar mobile phases.
Presented in part by A.P. Boichenko at the 4th Black Sea Basin Conference on Analytical Chemistry, 19–23 September, 2007,
Sunny Beach, Bulgaria. 相似文献
140.
Olga S. Finikova Dr. Artem Y. Lebedev Dr. Alexey Aprelev Dr. Thomas Troxler Dr. Feng Gao Dr. Carmen Garnacho Dr. Silvia Muro Prof. Robin M. Hochstrasser Prof. Sergei A. Vinogradov Prof. 《Chemphyschem》2008,9(12):1673-1679
High‐resolution images of oxygen distributions in microheterogeneous samples are obtained by two‐photon laser scanning microscopy (2P LSM), using a newly developed dendritic nanoprobe with internally enhanced two‐photon absorption (2PA) cross‐section. In this probe, energy is harvested by a 2PA antenna, which passes excitation onto a phosphorescent metalloporphyrin via intramolecular energy transfer. The 2P LSM allows sectioning of oxygen gradients with near diffraction‐limited resolution, and lifetime‐based acquisition eliminates dependence on the local probe concentration. The technique is validated on objects with a priori known oxygen distributions and applied to imaging of pO2 in cells. 相似文献