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911.
Nemtsev I. V. Shabanova O. V. Tambasov I. A. Ivanenko A. A. Cherepakhin A. V. Shestakov N. P. Zyryanov V. Ya. 《Journal of Structural Chemistry》2021,62(4):641-650
Journal of Structural Chemistry - Series of high-quality spherical poly(methyl methacrylate) particles with a polydispersity less than 5% are prepared by chain-growth emulsifier-free controlled... 相似文献
912.
Absorption spectrum of NbN has been obtained in the 560–670 nm region by intracavity laser spectroscopy. Vibrational and rotational analyses of 3φ - 3Δ transition has been caried out. Molecular constants for the upper (3φ) and ground (3Δ) states have been determined. 相似文献
913.
In this paper, we develop a new mixed Mann iteration process to approximate the fixed points of mixed increasing operators in ordered Banach spaces and discuss the convergence analysis of the iterative sequences generated by the iteration process. As an application, we develop a new iterative method for solving a class of nonlinear integral equations. 相似文献
914.
915.
Zhijie Fang Zhe Su Wenjing Qin Hao Li Bing Fang Wei Du Qiong Wu Bo Peng Peng Li Haidong Yu Lin Li Wei Huang 《中国化学快报》2021,31(11):2903-2908
H2S is an essential gas signal molecule in cells, and viscosity is a key internal environmental parameter. Recent studies have shown that H2S acts as a cytoarchitecture agent and gas transmitter in many tissues, e.g., as a regulator of neuroendocrine in the brain for mediating vascular tone in blood vessels. Mitochondrial viscosity is an important parameter for judging whether mitochondrial function is normal. It has been reported that oxidative stress and mitochondrial dysfunction are connected with Parkinson’s disease (PD), and the protective role of H2S in PD models has been extensively demonstrated. Herein, Mito-HS, a new two-photon fluorescent probe was demonstrated to detect cross-talk between the two channels of mitochondrial viscosity and H2S content. Moreover, this probe could detect the relative amount of and changes in mitochondrial H2S in situ due to the reduced mitochondrial targeting ability after reaction with H2S. The results show that H2S in mitochondria is inversely related to viscosity. The PD model has a lower H2S in mitochondria and a higher mitochondrial viscosity than did the normal. This result is important for our deep understanding of PD and its causes. 相似文献
916.
The fast transient fluorescence (FTRF) technique was used to study critical exponents at the glass transition in free-radical crosslinking copolymerization (FCC) for two different monomeric systems, methyl methacrylate (MMA) and styrene (S). Pyrene (Py ) was used as a fluorescence probe. The fluorescence lifetimes of Py from its decay traces were measured and used to monitor the gelation process. Changes in the viscosity of the pregel solutions due to glass formation dramatically enhance the fluorescent yield of aromatic molecules. This effect is used to study the glass transition upon gelation of MMA and S monomeric systems as a function of time, at various temperatures and crosslinker concentrations. The results are interpreted in the view of percolation theory. The gel fraction and weight average degree of polymerization exponents β and γ are found to be 0.37 ± 0.02 and 1.66 ± 0.07 in agreement with percolation results. 相似文献
917.
M. V. Tikhonova G. G. Garifullina A. Ya. Gerchikov S. I. Spivak 《Kinetics and Catalysis》2013,54(4):408-411
A new software package is suggested for solving the inverse kinetic problem for inhibited oxidation reactions of organic compounds. The software has been developed using inhibited n-decane oxidation as the model reaction. 相似文献
918.
V. G. Alekseev M. V. Golubeva Yu. Ya. Yakubovich 《Russian Journal of Inorganic Chemistry》2013,58(5):602-606
The complexation of Ln3+ ions with ampicillin anions (Amp?) in an aqueous solution at 25°C has been studied by pH titration on the background of 0.1 M KNO3. Ln(OH)Amp+ complexes are formed in neutral and weakly alkaline media. The logarithm of β increases nonlinearly along the lanthanide series from 9.02 ± 0.06 for Ce(OH)Amp+ to 10.25 ± 0.09 for Lu(OH)Amp+. The structure of the Lu(OH)Amp+ complex was simulated by the PM6 semiempirical quantum-chemical method and the MOPAC 2009 software; the results of which impliy the formation of a chelate complex via bidentate coordination of Amp? through the oxygen atoms of the carboxylate and β-lactam groups and the inclusion of up to five water molecules into the coordination sphere of Lu(III). 相似文献
919.
920.
Chia‐Shing Wu Ya‐Ju Yang Szu‐Wen Fang Yun Chen 《Journal of polymer science. Part A, Polymer chemistry》2012,50(18):3875-3884
This study reports the synthesis, curing, and optoelectronic properties of a solution‐processable, thermally cross‐linkable electron‐ and hole‐blocking material containing fluorene‐core and three periphery N‐phenyl‐N‐(4‐vinylphenyl)benzeneamine ( FTV ). The FTV exhibited good thermal stability with Td above 478 °C in nitrogen atmosphere. The FTV is readily cross‐linked via terminal vinyl groups by heating at 160 °C for 30 min to obtain homogeneous film with excellent solvent resistance. Multilayer PLED device [ITO/PEDOT:PSS/cured‐ FTV /MEH‐PPV/Ca (50 nm)/Al (100 nm)] was successfully fabricated using solution processed. Inserting cured‐ FTV is between PEDOT:PSS and MEH‐PPV results in simultaneous reduction in hole injection from PEDOT:PSS to MEH‐PPV and blocking in electron transport from MEH‐PPV to anode. The maximum luminance and maximum current efficiency were enhanced from 1810 and 0.27 to 4640 cd/m2 and 1.08 cd/A, respectively, after inserting cured‐ FTV layer. Current results demonstrate that the thermally cross‐linkable FTV enhances not only device efficiency but also film homogeneity after thermal curing. FTV is a promising electron‐ and hole‐blocking material applicable for the fabrication of multilayer PLEDs based on PPV derivatives. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 000: 000–000, 2012 相似文献