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31.
Journal of Computer and Systems Sciences International - Engineering systems contain actuators with force limits, so the level and rate saturation nonlinearities are often found in control systems.... 相似文献
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Yu Yang Zhiwei Zhou Bingchu Mei Yongqiang Zhang Xinwen Liu 《Ceramics International》2021,47(12):17139-17146
SrF2 transparent ceramic is a promising upconversion material due to the low phonon energy. The effect of different sintering temperatures on Er:SrF2 transparent ceramics was investigated. The suitable sintering temperature for Er:SrF2 transparent ceramics was 900 °C by hot-pressed sintering in this study. High quality of Er:SrF2 transparent ceramics with different doping concentrations were obtained. The upconversion luminescence spectra and decay behavior were compared between Er:SrF2 and Er:CaF2 transparent ceramics with different Er3+ doping concentration. The green emission of 5 at.% Er:SrF2 ceramic was much stronger than that of 5 at.% Er:CaF2 ceramic, while the red emission of Er:SrF2 ceramic was almost the same as that of Er:CaF2 ceramic. The upconversion luminescence lifetime of Er:SrF2 transparent ceramics was longer than that of Er:CaF2.All the results indicated Er:SrF2 transparent ceramics was a candidate for green fluorescent upconversion materials. 相似文献
34.
Avdeev Ya. G. Kuznetsov D. S. Kuznetsov Yu. I. 《Protection of Metals and Physical Chemistry of Surfaces》2021,57(7):1307-1312
Protection of Metals and Physical Chemistry of Surfaces - Impedance spectroscopy was used to study the adsorption of the IFKhAN-92 inhibitor, a triazole derivative, on cathodically polarized... 相似文献
35.
Quan-Qi Yu Juan-Juan Gao Xue-Xian Lang Hong-Yao Li Prof. Ming-Qi Wang 《Chembiochem : a European journal of chemical biology》2021,22(6):1042-1048
The development of small molecules that can selectively target G-quadruplex (G4) DNAs has drawn considerable attention due to their unique physiological and pathological functions. However, only a few molecules have been found to selectively bind a particular G4 DNA structure. We have developed a fluorescence ligand Q1 , a molecular scaffold with a carbazole–pyridine core bridged by a phenylboronic acid side chain, that acts as a selective ascaris telomere antiparallel G4 DNA ASC20 ligand with about 18 nm blue-shifted and enhanced fluorescence intensity. Photophysical properties revealed that Q1 was sensitive to the microenvironment and gave the best selectivity to ASC20 with an equilibrium binding constant Ka=6.04×105 M−1. Time-resolved fluorescence studies also demonstrated that Q1 showed a longer fluorescence lifetime in the presence of ASC20. The binding characteristics of Q1 with ASC20 were shown in detail in a fluorescent intercalator displacement (FID) assay, a 2-Ap titration experiment and by molecular docking. Ligand Q1 could adopt an appropriate pose at terminal G-quartets of ASC20 through multiple interactions including π–π stacking between aromatic rings; this led to strong fluorescence enhancement. In addition, a co-staining image showed that Q1 is mainly distributed in the cytoplasm. Accordingly, this work provides insights for the development of ligands that selectively targeting a specific G4 DNA structure. 相似文献
36.
Dr. Dae-Shik Kim Dr. Atsushi Endo Dr. Francis G. Fang Dr. Kuan-Chun Huang Dr. Xingfeng Bao Dr. Hyeong-wook Choi Dr. Utpal Majumder Dr. Young Y. Shen Steven Mathieu Xiaojie Zhu Kristen Sanders Dr. Thomas Noland Dr. Ming-Hong Hao Dr. Yu Chen Dr. John Y. Wang So Yasui Karen TenDyke Jiayi Wu Christy Ingersoll Kara A. Loiacono Dr. Janna E. Hutz Dr. Nadeem Sarwar 《ChemMedChem》2021,16(11):1741-1744
A strategy for creating potent and pan-genotypic stimulator of interferon genes (STING) agonists is described. Locking a bioactive U-shaped conformation of cyclic dinucleotides by introducing a transannular macrocyclic bridge between the nucleic acid bases leads to a topologically novel macrocycle-bridged STING agonist (MBSA). In addition to substantially enhanced potency, the newly designed MBSAs, exemplified by clinical candidate E7766 , exhibit broad pan-genotypic activity in all major human STING variants. E7766 is shown to have potent antitumor activity with long lasting immune memory response in a mouse liver metastatic tumor model. Two complementary stereoselective synthetic routes to E7766 are also described. 相似文献
37.
Angel L. Ortiz Camila S. Rodrigues Fernando Guiberteau Yu Zhang 《Journal of the European Ceramic Society》2021,41(11):5728-5739
The microstructural development during crystallization firing of a commercially-available dental-grade nanostructured lithia-zirconia glass-ceramic (Vita Suprinity® PC) was unraveled using a wide battery of ex-situ and in-situ characterization techniques. It was found that the milling blocks are slightly crystallized glass-ceramics, with a complex chemical composition and consisting of partially de-polymerized glass plus lithium silicate (Li2SiO3) nanocrystals. It was also found that during crystallization firing the glassy matrix first reacts with part of the Li2SiO3 to form lithium disilicate (Li2Si2O5) at ~810?820 °C, and then lithium orthophosphate (Li3PO4) precipitates from the glass. This results in glass-ceramics with abundant nanocrystals embedded in a sparse zirconosilicate glass matrix (containing many other cations subsumed) that, due to its high viscosity, inhibited crystal growth. Therefore, these dental glass-ceramics are not reinforced with zirconia (ZrO2) crystals unless over-fired above ~890 °C and at the expense of its singular nanostructure. Finally, this study opens doors for optimizing the clinical performance of these dental glass-ceramics via microstructural tailoring. 相似文献
38.
Volkovich A. G. Kolyadin V. I. Lemus A. V. Pavlenko V. I. Potapov V. N. Semenov S. G. Simirskii Yu. N. Chesnokov A. V. Shisha A. D. 《Atomic Energy》2021,129(6):349-355
Atomic Energy - The results of the dismantling of the active drain system and the decontamination of technological enclosures of the loop installations of the MR reactor, which is being... 相似文献
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40.
为了研究聚合物对水力旋流器内油滴聚结与分离效率的影响规律,以螺旋导流内锥式旋流器为研究对象,利用群体平衡模型(PBM)方法对不合聚与含聚0.5‰工况下油水两相在旋流器内的速度场、黏度场、油滴聚结、运移特性及分离效率进行数值分析,并通过实验验证.结果 表明:聚合物的加入增大了水相黏度,使油滴在旋流器内最大停留时间与轴向运动距离增加,增加了油滴碰撞聚结的机会,但降低轴心处油滴向上运动的轴向速度,使油滴无法快速从溢流口流出,最终从底流口流出,增加油水分离的难度.与不合聚时相比,含聚0.5‰工况下,轴心处的油滴粒径与含油体积分数较高,但简化分离效率由99.79%降低至94.72%.通过马尔文粒度仪对两种工况下入口与出口的油滴粒径进行测试,含聚0.5‰时溢流与底流口油滴粒径高于不合聚时,验证了模拟的准确性. 相似文献