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991.
We introduce a way to estimate the fluctuation of the refractive index during thin film deposition, through an optical monitor. The thicknesses and error-compensated thickness for each layer are analyzed. A novel monitoring method is thereby derived. The revised refractive index and the choice of highly sensitive monitoring wavelengths help us predict the termination points more accurately. The performance of a narrow-bandpass filter monitored by this method is demonstrated. 相似文献
992.
We experimentally demonstrate cavity linewidth control by manipulating dispersion of the intracavity medium. By making use of the dramatic change of Kerr nonlinearity near electromagnetically induced transparency resonance in a three-level atomic system, the cavity transmission linewidth can be greatly modified. As the cavity input intensity increases, the cavity linewidth changes from below to above empty cavity linewidth, corresponding to subluminal and superluminal photon propagation in the cavity, respectively. 相似文献
993.
Exact solutions for KdV system equations hierarchy are obtained by using the inverse scattering transform. Exact solutions of isospectral KdV hierarchy, nonisospectral KdV hierarchies and τ-equations related to the KdV spectral problem are obtained by reduction. The interaction of two solitons is investigated. 相似文献
994.
Chao Rong Wu Yan-Wei Lu Ling Xu Wei-Feng Wang Chang-Yun Shao Chang-Lun 《Chemistry of Natural Compounds》2021,57(2):343-345
Chemistry of Natural Compounds - Benzomalvins B, C, and E (1, 2, and 3) were simultaneously obtained from the marine fungus Aspergillus sp. isolated from the soft coral Sinularia sp., collected... 相似文献
995.
Chemistry of Natural Compounds - A novel cyclopropanoid, 4-(2-(benzo[d][1,3]dioxol-5-yl)cyclopropoxy)-2,6-dimethoxyphenol (1) was isolated from the stems of Cinnamomum osmophloeum (Lauraceae). The... 相似文献
996.
997.
Zongbo Xie Hongxia Li Bo Wang Zhiwen Wu Zhanggao Le 《Journal of heterocyclic chemistry》2021,58(8):1588-1593
A method for introducing a biologically active heterocycle, 2-methylquinoline into the 4-position of a 2-amino-4H-1-benzopyran skeleton is described. Choline chloride/glucose (1:1 molar ratio) was used as both the solvent and catalyst in the reaction of a salicylaldehyde, methylquinoline, and cyanoacetate to obtain 2-amino-4H-1-benzopyran derivatives in 48%–80% yields after short reaction times. The effects of the deep eutectic solvent type, substrate molar ratio, cosolvent, temperature, and reaction time were examined. The method has the advantages of simple steps, environmental friendliness, mild conditions, and wide substrate applicability. This is the first attempt to synthesize methylquinoline derivatives of 4H-1-benzopyran. 相似文献
998.
Dong-Yang Liu Xiao-Xia Ren Xiao-Min Ning Mei-Hua Lin Yuan-Di Wu Jing Qian 《无机化学与普通化学杂志》2021,647(1):8-14
To investigate the coordination chemistry of modbc (2-methyl-6-oxygen-1,6-dihydro-3,4'-bipyridine-5-carbonitrile) with ZnII and CdII salts under the solvothermal conditions, six new MOFs with the formulas [Zn(modbc)2(mpa)]n ( 1 ), [Zn(modbc)(mpa)(H2O)]n ( 2 ), [Zn(modbc)(pa)0.5(H2O)]n ( 3 ), [Cd(modbc)(pa)0.5(H2O)]n ( 4 ), [Zn(modbc)2(tpa)]n ( 5 ), and [Cd(modbc)2(pda)(H2O)]n ( 6 ) (mpa = m-phthalic acid; pa = pyromellitic acid; tpa = terephthalic acid; pda = pentane diacid) were successfully synthesized by solvothermal reaction and fully characterized by elemental analysis, IR spectroscopy, single crystal, powder X-ray diffraction, thermal and photoluminescence properties. Though MOFs 3 and 4 have the same structure, we have obtained three different kinds of coordination configurations by the X-ray diffration analysis. Compared with 1 and 2 , coordination water has no effect on the solid fluorescence emission of MOFs. It is worth noting that the fluorescence intensity of 3 containing central ZnII atoms is very strong, whereas that of isomorphism 4 containing central CdII atoms has almost no fluorescence emission, showing that metal ions have very important influence on the fluorescence emission. Further, we found that solvents had an important effect on the fluorescence emission in liquid fluorescence of MOFs 1 – 6 . 相似文献
999.
Saijie Wang Zhijian Liu Sen Wu Hongyan Sun Wu Zeng Jintao Wei Zixiao Fan Zhuohang Sui Liankun Liu Xinxiang Pan 《Electrophoresis》2021,42(21-22):2223-2229
To improve the accuracy and efficiency of ships’ ballast water detection, the separation of microalgae according to size is significant. In this article, a method to separate microalgae based on inertia-enhanced pinched flow fractionation (iPFF) was reported. The method utilized the inertial lift force induced by flow to separate microalgae according to size continuously. The experimental results show that, as the Reynolds number increases, the separation effect becomes better at first, but then stays unchanged. The best separation effect can be obtained when the Reynolds number is 12.3. In addition, with the increase of the flow rate ratio between sheath fluid and microalgae mixture, the separation effect becomes better and the best separation effect can be obtained when the flow rate ratio reaches 10. In this case, the recovery rate of Tetraselmis sp. is about 90%, and the purity is about 86%; the recovery rate of Chlorella sp. is as high as 99%, and the purity is about 99%. After that, the separation effect keeps getting better but very slowly. In general, this study provides a simple method for the separation of microalgae with different sizes, and lays a foundation for the accurate detection of microalgae in the ballast water. 相似文献
1000.
Kawamura Taiga Wu Hao Kim Seong-Yun 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):1001-1009
Journal of Radioanalytical and Nuclear Chemistry - (HDEHP?+?Hexa)/SiO2-P, a silica-based adsorbent, was prepared and used to separate Y(III) from a mixed solution of Sr(II) and Y(III).... 相似文献