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61.
Journal of Analytical Chemistry - The present study reports the development of a magnetic polyethylene glycol nanocomposite based on graphite reinforcement carbon paste electrode for the sensitive... 相似文献
62.
Varfolomeev S. D. Panin A. A. Semenova N. A. Ublinskiy M. V. Akhadov T. A. Bykov V. I. Tsybenova S. B. 《Russian Chemical Bulletin》2022,71(3):591-594
A kinetic study of the effect of thermoheliox (inhalation of a helium and oxygen mixture, 70 °C) on the functional hemodynamics of the human brain by functional magnetic resonance imaging was carried out. The dynamic responses of the BOLD signal were found to be biphasic. An empirical equation describing the first phase of the hemodynamic response to visual stimulus was proposed. It was shown that preliminary inhalation of thermoheliox stimulates the hemodynamic responses by slowing down the vasoconstriction.
相似文献63.
Russian Journal of Organic Chemistry - A highly efficient green protocol has been proposed for the synthesis of symmetrical S-aryl arenesulfonothioates by irradiation of N-hydroxy arenesulfonamides... 相似文献
64.
Numerical Algorithms - In this work, we propose a fractional extension of the one-dimensional nonlinear vibration problem on an elastic string. The fractional problem is governed by a hyperbolic... 相似文献
65.
Siberian Mathematical Journal - Let $ \{(A_{i},B_{i})\}_{i=1}^{m} $ be a set pair system. Füredi, Gyárfás, and Király called it $ 1 $ -cross intersecting if $... 相似文献
66.
Theoretical and Mathematical Physics - Dynamic systems acting on the plane and possessing the Wada property have been observed. There exist only two topological types, symmetric and antisymmetric,... 相似文献
67.
Mathematical Notes - Subspaces of the space of analytic functions on a convex domain in the complex plane that are invariant with respect to the differentiation operator are studied. The problem of... 相似文献
68.
Hao Lu Xiaodong Wang Hang Wang Andong Zhang Xinming Zheng Na Yu Zheng Tang Xinjun Xu Yahui Liu Ya-Nan Chen Zhishan Bo 《中国科学:化学(英文版)》2022,65(3):594-601
Three nonfused ring electron acceptors (NFREAs) TTC6,TT-C8T and TT-TC8 were purposefully designed and synthesized.The molecular geometry can be adjusted by the steric hindrance of lateral substituents.According to the DFT calculations,from TTC6 to TT-C8T and TT-TC8,planarity of the molecular backbone is gradually improved,accompanying with the enhancing of intramolecular charge transfer effect.As for TT-TC8,the two phenyl substituents are almost perpendicular to the molecular backbone,which endues the acceptor with good solubility and suppresses it to form over-aggregation.Multidirectional regular molecular orientation and closer molecular stacking are formed in TT-TC8 film.As a result,TT-TC8 based devices afford the highest PCE of 13.13%,which is much higher than that of TTC6 (4.41%) and TT-C8T (10.42%) and among the highest PCE values based on NFREAs. 相似文献
69.
Prof. Dr. Peter Hess 《Chemphyschem》2022,23(6):e202100880
In the periodic table the position of each atom follows the ‘aufbau’ principle of the individual electron shells. The resulting intrinsic periodicity of atomic properties determines the overall behavior of atoms in two-dimensional (2D) bonding and structure formation. Insight into the type and strength of bonding is the key in the discovery of innovative 2D materials. The primary features of 2D bonding and the ensuing monolayer structures of the main-group II–VI elements result from the number of valence electrons and the change of atom size, which determine the type of hybridization. The results reveal the tight connection between strength of bonding and bond length in 2D networks. The predictive power of the periodic table reveals general rules of bonding, the bonding-structure relationship, and allows an assessment of published data of 2D materials. 相似文献
70.
Mohammad A. Khalilzadeh Soo Young Kim Ho Won Jang Rafael Luque Rajender S. Varma Richard A. Venditti Mohammadreza Shokouhimehr 《Materials Today Chemistry》2022
The requirement of green and sustainable materials to prepare heterogeneous catalysts has intensified for practical reasons over the past few decades. Carbohydrates are possibly the most plentiful and renewable organic materials in nature with inimitable physiochemical properties, plausible low-cost and large-scale production, and sustainability features could be exploited in the generation of nanostructured heterogeneous catalysts. This review article outlines the organic transformations catalyzed by diverse carbohydrate-based nanostructured catalysts in greener and environmentally friendly processes. Selected examples are highlighted for a variety of organic reactions exploiting the proposed catalysts’ reactivity and reusability, and interactions with the intrinsic nature of the applied carbohydrate supports; advantages and speculated challenges of the introduced catalysts are deliberated as well. 相似文献