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11.
A novel metal-doped metal–organic framework (MOF) was developed by incorporating salen–Mg into NH2–MIL-101(Cr) structure under ambient conditions. The Schiff base complex was successfully prepared by condensing salicylaldehyde with a free amino group and then coordinating metal ions. Such a structure can endow the sample with higher CO2 adsorption performance. At 0°C and 1 bar, the salen–Mg-modified sample achieves the maximum adsorption capacity of 2.18 mmol g−1 for CO2, which was 5.8% higher than the pristine salen–MOF under the same conditions. Notably, the Freundlich model indicates that the CO2 adsorption process of all samples conforms to reversible adsorption. However, the correlation coefficients (R2) of the Mg-doped sample are lower than that of the pristine sample. Besides, the CO2/N2 adsorption selectivity and isosteric heat also show a similar trend. These results indicate that the salen–Mg can enhance the interaction between the material and CO2 molecules. 相似文献
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The rapid transmission of vaccinia virus(VACV)in vivo is thought to be closely related to the cell migration induced by it.Cell migration involved in dynamic changes of cell-substrate adhesion and actin cytoskeleton organization,which can influence by the micro/nano-scale topographic structures that cells are naturally exposed to via contact guidance.However,migration behaviors of VACV-infected cells exposed to topographic cues are still unknown.Herein,we designed an open chip with microgrooved poly(dimethyl siloxane)(PDMS)substrate to explore the topography roles in VACV-induced cell migration.Differed from the random cell migration observed in traditional scratch assay on planar substrate,VACV-infected cells had a tendency to persistently migrate along the axis parallel to microgroove with increased velocity.Moreover,infected cells exhibited a dominant elongated protrusion aligned to the micro-grating axis compare to the shorter lamella extended in any direction on smooth substrate.Interestingly,the Golgi complex preferred to relocate behind the nucleus confined within the micro-grating axis in majority of infected migratory cells.The directional polarization of cells embodied in protrusion formation and Golgi reorientation was responsible for the directionally persistent migration behaviors induced by VACV on microgrooved substrate.Infected cells response to substrate topography,causing the actin-filled stretched protrusion containing numerous virions and accelerated movement is likely to facilitate direct and rapid spread of VACV.This work opens a window for us to understand the migration behaviors of infected cells in vivo,and also provides a cue for revealing the relationship between virus-induced cell migration and virus rapid spread. 相似文献
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Meccanica - This paper introduces an analytical approach to optimize the textured bearing with cavitation to improve the load support. For this purpose, a grooved parallel slider bearing is... 相似文献
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CongZhan Liu YiFei Zhang XuFang Li XueFeng Lu Zhi Chang ZhengWei Li AiMei Zhang YongJie Jin HuiMing Yu Zhao Zhang MinXue Fu YiBao Chen JianFeng Ji YuPeng Xu JingKang Deng RenCheng Shang GuoQing Liu FangJun Lu ShuangNan Zhang YongWei Dong TiPei Li Mei Wu YanGuo Li HuanYu Wang BoBing Wu YongJie Zhang Zhi Zhang ShaoLin Xiong Yuan Liu Shu Zhang HongWei Liu YiJung Yang Fan Zhang 《中国科学:物理学 力学 天文学(英文版)》2020,(4):20-34
The Insight-Hard X-ray Modulation Telescope(Insight-HXMT) is a broadband X-ray and γ-ray(1-3000 ke V) astronomy satellite. One of its three main telescopes is the High Energy X-ray telescope(HE). The main detector plane of HE comprises 18 Na I(Tl)/Cs I(Na) phoswich detectors, where Na I(Tl) is used as the primary detector to measure ~ 20-250 ke V photons incident from the field of view(FOV) defined by collimators, and Cs I(Na) is used as the active shielding detector to Na I(Tl) by pulse shape discrimination. Additionally, Cs I(Na) is used as an omnidirectional γ-ray monitor. The HE collimators have a diverse FOV,i.e. 1.1°×5.7°(15 units), 5.7°×5.7°(2 units), and blocked(1 unit). Therefore, the combined FOV of HE is approximately5.7°×5.7°. Each HE detector has a diameter of 190 mm resulting in a total geometrical area of approximately 5100 cm2, and the energy resolution is ~15% at 60 ke V. For each recorded X-ray event by HE, the timing accuracy is less than 10 μs and the deadtime is less than 10 μs. HE is used for observing spectra and temporal variability of X-ray sources in the 20-250 ke V band either by pointing observations for known sources or scanning observations to unveil new sources. Additionally, HE is used for monitoring the γ-ray burst in 0.2-3 Me V band. This paper not only presents the design and performance of HE instruments but also reports results of the on-ground calibration experiments. 相似文献
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Dr. Li Xu Xiang Chen Jingheng Wu Jinquan Wang Prof. Liangnian Ji Prof. Dr. Hui Chao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):4008-4020
A series of dinuclear ruthenium(II) complexes were synthesised, and the complexes were determined to be new highly selective compounds for binding to telomeric G‐quadruplex DNA. The interactions of these complexes with telomeric G‐quadruplex DNA were studied by using circular dichroism (CD) spectroscopy, fluorescence resonance energy transfer (FRET) melting assays, isothermal titration calorimetry (ITC) and molecular modelling. The results showed that the complexes 1 , 2 and 4 induced and stabilised the formation of antiparallel G‐quadruplexes of telomeric DNA in the absence of salt or in the presence of 100 mM K+‐containing buffer. Furthermore, complexes 1 and 2 strongly bind to and effectively stabilise the telomeric G‐quadruplex structure and have significant selectivity for G‐quadruplex over duplex DNA. In comparison, complex 3 had a much lesser effect on the G‐quadruplex, suggesting that possession of a suitably sized plane for good π–π stacking with the G‐quadruplets is essential for the interaction of the dinuclear ruthenium(II) complexes with the G‐quadruplex. Moreover, telomerase inhibition by the four complexes and their cellular effects were studied, and complex 1 was determined to be the most promising inhibitor of both telomerase and HeLa cell proliferation. 相似文献
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TBAI‐Catalyzed/Water‐Assisted Double C−S Bond Formations: An Efficient Approach to Sulfides through Metal‐Free Three‐Component Reactions 下载免费PDF全文
Xue‐Qiang Chu Prof. Dr. Xiao‐Ping Xu Prof. Dr. Shun‐Jun Ji 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14181-14185
An aqueous catalytic method for double C?S bond formations that involves alcohol derivatives, organic halides, and sodium thiosulfate has been developed. A diverse range of functionalized sulfides, including pharmaceutical and biological derivatives, can be obtained in an efficient and eco‐friendly manner under air. The mechanistic studies revealed that this tetrabutylammonium‐iodide‐catalyzed/water‐assisted reaction generated a mercaptan species as the key intermediate. 相似文献