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991.
High‐Level Incorporation of Silver in Gold Nanoclusters: Fluorescence Redshift upon Interaction with Hydrogen Peroxide and Fluorescence Enhancement with Herbicide 下载免费PDF全文
Dr. Guijian Guan Dr. Yongqing Cai Dr. Shuhua Liu Dr. Haidong Yu Dr. Shiqiang Bai Dr. Yuan Cheng Dr. Tao Tang Dr. M. S. Bharathi Prof. Yong‐Wei Zhang Prof. Ming‐Yong Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(5):1675-1681
High‐level incorporation of Ag in Au nanoclusters (NCs) is conveniently achieved by controlling the concentration of Ag+ in the synthesis of bovine serum albumin (BSA)‐protected Au NCs, and the resulting structure is determined to be bimetallic Ag28Au10‐BSA NCs through a series of characterizations including energy‐dispersive X‐ray spectroscopy, mass spectroscopy, and X‐ray photoelectron spectroscopy, together with density functional theory simulations. Interestingly, the Ag28Au10 NCs exhibit a significant fluorescence redshift rather than quenching upon interaction with hydrogen peroxide, providing a new approach to the detection of hydrogen peroxide through direct comparison of their fluorescence peaks. Furthermore, the Ag28Au10 NCs are also used for the sensitive and selective detection of herbicide through fluorescence enhancement. The detection limit for herbicide (0.1 nm ) is far below the health value established by the U.S. Environmental Protection Agency; such sensitive detection was not achieved by using AuAg NCs with low‐level incorporation of Ag or by using the individual metal NCs. 相似文献
992.
Ie. V. Gubareni Ya. P. Kurilets S. O. Soloviev 《Theoretical and Experimental Chemistry》2016,52(5):323-330
993.
Andreiy A. Gushchin Vladimir I. Grinevich Valeriy Ya. Shulyk Elena Yu. Kvitkova Vladimir V. Rybkin 《Plasma Chemistry and Plasma Processing》2018,38(1):123-134
The processes of degradation of 2,4-dichlorophenol (2,4-DCP) aqueous solutions under the action of atmospheric pressure of DBD in oxygen were studied. The degradation of 2,4-DCP proceeds efficiently, the degree of decomposition reaching 100%. The degradation kinetics of 2,4-DCP obeys a formal first-order kinetic law on concentration of 2,4-DCP. The effective rate constants depend weakly on the experimental conditions and are equal to ~ 2 s?1. Based on experimental data, the energy efficiency of 2,4-DCP decomposition was determined to be in the range of 0.039–0.173 molecules per 100 eV depending on the experimental conditions. The composition of the products was studied by gas chromatography, chromatography-mass spectrometry, UV/visible spectroscopy, fluorescent methods and some chemical methods. The main decomposition products present in the solution were found to be carboxylic acids, aldehydes and chloride ions, whereas carbon dioxide and molecular chlorine appear in the gas. The results obtained are compared with similar data from other advanced oxidation processes (AOP’s) methods. 相似文献
994.
V. A. Sapozhnikov N. K. Chameeva V. Ya. Mitrofanov A. E. Nikiforov A. N. Men 《光谱学快报》2013,46(11):571-574
The calculation of relative intensities of the optical absorption lines of the fourth order pair of Cr3+ ions in ruby has been performed assuming the electro-dipole character of the transitions. 相似文献
995.
996.
Qing-Long Bai Chun-Hua Zhang Juan-Juan Song Jing-Hai Liu Yan-Chun Feng Li-Mei Duan Chuan-Hui Cheng 《中国化学快报》2016,27(5):764-768
A metal-free purple H2Pc single crystal was synthesized by a facile solvothermal method, and its solubility and near-infrared (NIR) optical properties were also investigated due to its potential applications as a light-emitting layer for OLEDs. The H2Pc single crystal is insoluble in 1-chlorine naphthalene and other organic solvents. It gives a wide absorption in the range from 620 nm to 679 nm and a wide emission in near 922 nm. As an active light-emitting layer, H2Pc was employed to fabricate electroluminescent (EL) devices with a structure of ITO/NPB (30 nm)/Alq3:H2Pc (30 nm)/BCP (20 nm)/Alq3 (20 nm)/Al. The emission center is at 936 nm when the H2Pc doping concentration is 20 wt%. The doping concentration strongly governs the emission intensity. When doping concentration decreases from 10 wt% to 1 wt%, the emission intensity remarkably fades, and simultaneously the emission center undergoes a blue shift. 相似文献
997.
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
998.
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
999.
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
1000.