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121.
Shanshan Qin Lancang Shui Benedict Osuagwu Nikita Denisov Dr. Alexander B. Tesler Prof. Patrik Schmuki 《ChemistryOpen》2022,11(3):e202200010
Titanium dioxide (TiO2) and, in particular, its anatase polymorph, is widely studied for photocatalytic H2 production. In the present work, we examine the importance of reactive facets of anatase crystallites on the photocatalytic H2 evolution from aqueous methanol solutions. For this, we synthesized anatase TiO2 nanocrystals with a large amount of either {001} facets, that is, nanosheets, or {101} facets, that is, octahedral nanocubes, and examined their photocatalytic H2 evolution and then repeated this procedure with samples where Pt co-catalyst is present on all facets. Octahedral nanocubes with abundant {101} facets produce >4 times more H2 than nanosheets enriched in {001} facets if the reaction is carried out under co-catalyst-free conditions. For samples that carry Pt co-catalyst on both {001} and {101} facets, faceting loses entirely its significance. This demonstrates that the beneficial role of faceting, namely the introduction of {101} facets that act as electron transfer mediator is relevant only for co-catalyst-free TiO2 surfaces. 相似文献
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Victor I. Sokolov Sergey F. Dubinin Vitaliy D. Parkhomenko Vladimir V. Gudkov Alexander V. Tkach Nikita B. Gruzdev 《Solid State Communications》2004,129(8):507-510
Neutron diffraction and ultrasonic experiments as well as measurements of heat conductivity in ZnSe and Zn1−xNixSe (x=0.0025) semiconductors have been carried out. As a result, a structural transition induced by Ni impurity has been found at 相似文献
125.
Tawanda Gwena 《Proceedings of the American Mathematical Society》2005,133(5):1317-1323
We present a surprising connection between cubic threefolds and the well-known regular matroid by making use of intermediate Jacobians of cubic threefolds realized as Prym varieties. As a corollary we obtain a new proof of the nonrationality of generic cubic threefolds.
126.
尼基塔·莫洛佐夫 《宁波大学学报(理工版)》2000,13(2):6-11
含有限裂纹的弹性板是裂纹理论中的基本问题,作者将著名的Dines,Parkin,Qrtiz等的离散解与连续解Novozhilov和Thomson的杂交解进行了比较,对Thomson与Novozhilov的模型进行了全面的对比,分析了Novozhilov的R-子数和Thomson的点阵函数的特性,利用Thomson模型证明了“断裂孤立子”理论的存在,解释了Cherny-kozorezov模型中的松驰 相似文献
127.
Nikita K. Kulachenkov Dr. Dapeng Sun Yuri A. Mezenov Dr. Andrei N. Yankin Sergey Rzhevskiy Dr. Vyacheslav Dyachuk Dr. Alexandre Nominé Dr. Ghouti Medjahdi Prof. Evgeny A. Pidko Dr. Valentin A. Milichko 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(36):15652-15656
We demonstrate herein an all-optical switch based on stimuli-responsive and photochromic-free metal–organic framework (HKUST-1). Ultrafast near-infrared laser pulses stimulate a reversible 0.4 eV blue shift of the absorption band with up to 200 s−1 rate due to dehydration and concomitant shrinking of the structure-forming [Cu2C4O8] cages of HKUST-1. Such light-induced switching enables the remote modulation of intensities of photoluminescence of single crystals of HKUST-1 as well visible radiation passing through the crystal by 2 order of magnitude. This opens up the possibility of utilyzing stimuli-responsive MOFs for all-optical data processing devices. 相似文献
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Zoran Andelkovic Gerhard Birkl Svetlana Fedotova Volker Hannen Frank Herfurth Kristian König Nikita Kotovskiy Bernhard Maaß Jonas Vollbrecht Tobias Murböck Dennis Neidherr Wilfried Nörtershäuser Stefan Schmidt Manuel Vogel Gleb Vorobjev Christian Weinheimer 《Hyperfine Interactions》2015,231(1-3):37-44
Heavy few-electron ions are relatively simple systems in terms of electron structure and offer unique opportunities to conduct experiments under extremely large electromagnetic fields that exist around their nuclei. However, the preparation of highly charged ions (HCI) has remained the major challenge for experiments. As an extension of the existing GSI accelerator facility, the HITRAP facility was conceived as a multi-stage decelerator for HCI produced at high velocity. It is designed to prepare bunches of around 105 HCI and to deliver them at low energies to various experiments. One of these experiments is SpecTrap, aiming for laser spectroscopy of trapped, cold HCI. We present the latest results on deceleration of ions in a radio-frequency quadrupole, synchrotron cooling of electrons in a trap as a preparation step for the prospective electron cooling of the HCI decelerated in HITRAP, as well as laser cooling of singly charged Mg ions for sympathetic cooling of HCI in SpecTrap. 相似文献
130.
Konstantin L. Ivanov Dmitri V. Stass Evgeny V. Kalneus Robert Kaptein Nikita N. Lukzen 《Applied magnetic resonance》2013,44(1-2):217-232
In this work we have compared manifestations of degenerate electron exchange (DEE) and dimerization reactions in MARY (magnetically affected reaction yield) spectroscopy and time-resolved magnetic field effects (TR-MFE) of radical ion pairs (RIPs). It is shown that dimerization results in phase and frequency changes of the quantum beats in TR-MFE traces, whereas DEE leads to relaxation-type changes in the spin dynamics of RIPs. Dimerization does not change the width of MARY lines considerably, but leads to new lines corresponding to dimer radical ions. In contrast, DEE substantially changes the MARY line widths. Our treatment provides ways to discriminate between both processes from experimental MARY spectra and TR-MFE kinetics. An experimental example dealing with concentration-dependent broadening of the MARY lines is also discussed. 相似文献