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61.
The surface characteristics of titanium oxide films evaluated by gray level co-occurrence matrices (GLCMs) and entropy are demonstrated experimentally. A PC-based measurement system was set up to detect the interference fringe of optical coating surface as captured by a Fizeau interferometer. Titanium oxide films were prepared by an electron-beam gun evaporation method. The proposed measuring system was used to evaluate the surface flatness of titanium oxide films coated on glass substrates. The variation of entropy in titanium oxide films before and after film deposition was found to be related to the root-mean-square (rms) surface roughness. Surface characteristics of thin films were fast measured by our proposed method and the test results were verified by atomic force microscopy (AFM) and scanning electrical microscopy (SEM). 相似文献
62.
Jun-Rui Lyu Shao-Yi Wu Yu-Jing Hong Hao Wu Hui-Ning Dong 《Magnetic resonance in chemistry : MRC》2022,60(3):398-406
In this work, the g factors, d–d transition band, local distortion, and their concentration dependences for impurity V4+ in 20Li2O–20PbO–45B2O3–(15 − x)P2O5:V2O5 (0 ≤ x ≤ 2.5 mol%) glasses are theoretically investigated by using perturbation formulas of g factors for a tetragonally compressed octahedral 3d1 cluster. In the light of the cubic polynomial concentration functions for cubic field parameter Dq, covalency factor N, and relative tetragonal compression ratio ρ, the calculated concentration dependences of d–d transition band and g factors for V4+ show good agreement with the experimental data. With increasing x, N (≈0.7682–0.8165) displays the monotonously increasing trend, whereas ρ (≈6.5–4.2%) and Dq (≈1504.9–1481.1 cm−1) exhibit the decreasing tendencies. The above concentration dependences can be ascribed to the modifications of the V4+–O2− bonding and orbital admixtures around the impurity V4+ due to the effects of V2O5 doping on the stability of the glass network, the strength of local crystal fields, and the electron cloud distribution. 相似文献
63.
64.
Dr. Yui Sasaki Satoshi Ito Zhoujie Zhang Xiaojun Lyu Dr. Shin-ya Takizawa Dr. Riku Kubota Prof. Dr. Tsuyoshi Minami 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(69):16236-16240
An artificial tongue that detects astringent components for a comprehensive evaluation of taste has not been established to date. Herein, we first propose fluorescent polythiophene (PT) derivatives ( S1 – S3 ) modified with 3-pyridinium boronic acid as supramolecular chemosensors for wine components including astringent procyanidin C1. After numerous attempts for the synthetic conditions, more than 95 mol % of the PT unit was modified with the pyridinium boronic acid moiety. To evaluate the PT derivatives as chemosensors of the artificial tongue, qualitative and quantitative analyses were performed with four types of wine components (i.e., sweet, sour, bitter, and astringent tastes) in combination with pattern recognition models. Notably, procyanidin C1 in the actual wine sample was successfully detected in a quantitative manner. In other words, we have established an authentic artificial tongue using PT based supramolecular chemosensors. 相似文献
65.
66.
Lyu Jiahui Han Huibin Wu Qiong Ma Hongchao Ma Chun Dong Xiaoli Fu Yinghuan 《Journal of Solid State Electrochemistry》2019,23(3):847-859
Journal of Solid State Electrochemistry - Rational hydrophobic anode has been considered as a promising approach for water pollution remediation. However, the construction method of the hydrophobic... 相似文献
67.
Weiqiang Tan Jifang Zheng Jing Guan Xiuzhi Zhan Liming Gao Lili Lyu Bin Shan Qipeng Yang Mingliang Ma Yan Xia 《Journal of heterocyclic chemistry》2020,57(3):1003-1010
One-step synthesis of 9-anthrone lactone derivatives from 1-acetyloxyanthraquinone with a variety of dicarbonyl substrates in the presence of K2CO3 by Knovenagel condensation and intramolecular cyclization is developed. Possible reaction mechanisms have been investigated using the density functional theory (DFT), which has been widely used in the study of reaction mechanism. The strategy could be useful for the synthesis of the core structure of marine natural product aspergiolide. 相似文献
68.
Wan Yupeng Lyu Heng Du Hengyi Wang Dunjia Yin Guodong 《Research on Chemical Intermediates》2019,45(4):1669-1687
Research on Chemical Intermediates - Two pentafluorinated β-diketone ligands, 4,4,5,5,5-pentafluoro-1-(4-methoxyphenyl)pentane-1,3-dione (PFMP) and 4,4,5,5,5-pentafluoro-1-(4-dimethyl... 相似文献
69.
A coordinate transformation technique between straight magnetic field line coordinate system (Ψ, θ) and Cartesian coordinate system (R, Z) is presented employing a Solov'ev solution of the Grad-Shafranov equation. Employing the equilibrium solution, the poloidal magnetic flux Ψ(R, Z) of a diverted tokamak, magnetic field line equation is solved computationally to find curves of constant poloidal angle θ, which provides us with explicit relations R = R(Ψ, θ) and Z = Z(Ψ, θ). Correspondingly, conversion from one coordinate to the other along particle trajectories in the vicinity of separatrix is demonstrated. Based on the magnetic structure, a finite element mesh is generated in a diverted tokamak geometry to solve Poisson's equation. 相似文献
70.
We consider the Hankel determinant generated by the Gaussian weight with two jump discontinuities. Utilizing the results of Min and Chen [Math. Methods Appl Sci. 2019;42:301‐321] where a second‐order partial differential equation (PDE) was deduced for the log derivative of the Hankel determinant by using the ladder operators adapted to orthogonal polynomials, we derive the coupled Painlevé IV system which was established in Wu and Xu [arXiv: 2002.11240v2] by a study of the Riemann‐Hilbert problem for orthogonal polynomials. Under double scaling, we show that, as , the log derivative of the Hankel determinant in the scaled variables tends to the Hamiltonian of a coupled Painlevé II system and it satisfies a second‐order PDE. In addition, we obtain the asymptotics for the recurrence coefficients of orthogonal polynomials, which are connected with the solutions of the coupled Painlevé II system. 相似文献