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991.
Chaosheng Yuan Lei Su Kun Yang Zijiong Li Xuerui Cheng Weiqing Zhou Liangbin Li 《Journal of Sol-Gel Science and Technology》2014,72(2):344-350
Sol–gel transition behavior of ionic liquid gel based on poly (ethylene glycol) (PEG) and ionic liquid 1-ethyl-3-methylimidazolium ethylsulfate [EMIM][EtSO4] has been investigated under the pressure up to 250 MPa. The Temperature versus Pressure phase diagram of PEG/[EMIM][EtSO4] gel is constructed, and it indicates that the melting point is an increasing function of pressure. Based on the phase diagram, the PEG/[EMIM][EtSO4] gels are prepared by cooling under the pressure of 300 MPa and atmospheric pressure, respectively. From the differential scanning calorimetry result of the recovered samples, it is found that PEG/[EMIM][EtSO4] gel prepared under high pressure has a higher crystallinity and smaller crystal size polymer network, comparing with under atmospheric pressure. The cyclic voltammograms and impedance spectra tests indicate that the PEG/[EMIM][EtSO4] gel prepared under high pressure exhibit higher ionic conductivity comparing with atmospheric pressure. It could be speculated these excellent properties might be attributed to the loose gel structure and high ionic density induced by high pressure. 相似文献
992.
Shuyuan Zheng Tianwen Zhu Yunzhong Wang Tianjia Yang Prof. Wang Zhang Yuan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(25):10104-10108
Nonaromatic, cross-conjugated, and highly twisted luminogens consisting of acylated succinimides demonstrate aggregation-induced emission characteristics along with tunable multicolor photoluminescence and afterglows in their single crystals. Effective through-space conjugation among different moieties bearing n/π electrons promote the spin–orbit coupling and intersystem crossing and lead to diverse emissive clusters with concurrently rigidified conformations, thus allowing readily tunable emissions. Derived from it, the proof-of-concept application for advanced anti-counterfeiting is illustrated. These results should spur the rational design of novel nonaromatic AIEgens, and moreover advance understandings of the non-traditional intrinsic luminescence and the origin of tunable multicolor afterglows. 相似文献
993.
Jialuo Li Shuai Yuan Jun-Sheng Qin Jiandong Pang Peng Zhang Yingmu Zhang Yanyan Huang Hannah F. Drake Wenshe R. Liu Prof. Dr. Hong-Cai Zhou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9405-9409
The controlled synthesis of multicomponent metal–organic frameworks (MOFs) allows for the precise placement of multiple cooperative functional groups within a framework, leading to emergent synergistic effects. Herein, we demonstrate that turn-on fluorescence sensors can be assembled by combining a fluorophore and a recognition moiety within a complex cavity of a multicomponent MOF. An anthracene-based fluorescent linker and a hemicyanine-containing CN−-responsive linker were sequentially installed into the lattice of PCN-700. The selective binding of CN− to hemicyanine inhibited the energy transfer between the two moieties, resulting in a fluorescence turn-on effect. Taking advantage of the high tunability of the MOF platform, the ratio between anthracene and the hemicyanine moiety could be fine-tuned in order to maximize the sensitivity of the overall framework. The optimized MOF-sensor had a CN−-detection limit of 0.05 μm , which is much lower than traditional CN− fluorescent sensors (about 0.2 μm ). 相似文献
994.
Dr. Nan Chen Dr. Yuan Liu Yuanpei Li Prof. Dr. Chu Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16203-16209
Protein 4′-phosphopantetheinylation is an essential post-translational modification (PTM) in prokaryotes and eukaryotes. So far, only five protein substrates of this specific PTM have been discovered in mammalian cells. These proteins are known to perform important functions, including fatty acid biosynthesis and folate metabolism, as well as β-alanine activation. To explore existing and new substrates of 4′-phosphopantetheinylation in mammalian proteomes, we designed and synthesized a series of new pantetheine analogue probes, enabling effective metabolic labelling of 4′-phosphopantetheinylated proteins in HepG2 cells. In combination with a quantitative chemical proteomic platform, we enriched and identified all the currently known 4′-phosphopantetheinylated proteins with high confidence, and unambiguously determined their exact sites of modification. More encouragingly, we discovered, using targeted chemical proteomics, a potential 4′-phosphopantetheinylation site in the protein of mitochondrial dehydrogenase/reductase SDR family member 2 (DHRS2). 相似文献
995.
Rational Design of Cyclometalated Iridium(III) Complexes for Three-Photon Phosphorescence Bioimaging
Dr. Chengzhi Jin Fengyin Liang Dr. Jinquan Wang Dr. Lili Wang Dr. Jiangping Liu Xinxing Liao Dr. Thomas W. Rees Bo Yuan Prof. Dr. Hui Wang Prof. Dr. Yong Shen Prof. Dr. Zhong Pei Prof. Dr. Liangnian Ji Prof. Dr. Hui Chao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16121-16125
Compared to 2PE (two-photon excitation) microscopy, 3PE microscopy has superior spatial resolution, deeper tissue penetration, and less defocused interference. The design of suitable agents with a large Stokes shift, good three-photon absorption (3PA), subcellular targeting, and fluorescence lifetime imaging (FLIM) properties, is challenging. Now, two IrIII complexes (3PAIr1 and 3PAIr2) were developed as efficient three-photon phosphorescence (3PP) agents. Calculations reveal that the introduction of a new group to the molecular scaffold confers a quadruple promotion in three-photon transition probability. Confocal and lifetime imaging of mitochondria using IrIII complexes as 3PP agents is shown. The complexes exhibit low working concentration (50 nm ), fast uptake (5 min), and low threshold for three-photon excitation power (0.5 mW at 980 nm). The impressive tissue penetration depth (ca. 450 μm) allowed the 3D imaging and reconstruction of brain vasculature from a living specimen. 相似文献
996.
Prof. Dr. Su-Yun Zhang Dr. Han Miao Dr. He-min Zhang Jun-Hao Zhou Prof. Dr. Qiang Zhuang Prof. Dr. Yu-Jia Zeng Prof. Dr. Zhiming Gao Prof. Dr. Jiayin Yuan Prof. Dr. Jian-Ke Sun 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22293-22300
The capability to significantly shorten the synthetic period of a broad spectrum of open organic materials presents an enticing prospect for materials processing and applications. Herein we discovered 1,2,4-triazolium poly(ionic liquid)s (PILs) could serve as a universal additive to accelerate by at least one order of magnitude the growth rate of representative imine-linked crystalline open organics, including organic cages, covalent organic frameworks (COFs), and macrocycles. This phenomenon results from the active C5-protons in poly(1,2,4-triazolium)s that catalyze the formation of imine bonds, and the simultaneous salting-out effect (induced precipitation by decreasing solubility) that PILs exert on these crystallizing species. 相似文献
997.
Yuan Xu Jing Xue Qing Zhou Yongjun Zheng Xinghua Chen Prof. Songqin Liu Prof. Yanfei Shen Prof. Yuanjian Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(34):14606-14611
Emerging as a cost-effective and robust enzyme mimic, nanozymes have drawn increasing attention with broad applications ranging from cancer therapy to biosensing. Developing nanozymes with both accelerated and inhibited biocatalytic properties in a biological context is intriguing to peruse more advanced functions of natural enzymes, but remains challenging, because most nanozymes are lack of enzyme-like molecular structures. By re-visiting and engineering the well-known Fe-N-C electrocatalyst that has a heme-like Fe-Nx active sites, herein, it is reported that Fe-N-C could not only catalyze drug metabolization but also had inhibition behaviors similar to cytochrome P450 (CYP), endowing it a potential replacement of CYP for preliminary evaluation of massive potential chemicals, drug dosing guide, and outcome prediction. In addition, in contrast to electrocatalysts, the highly graphitic framework of Fe-N-C may not be obligatory for a competitive CYP-like activity. 相似文献
998.
Dr. Xueting Pan Dr. Weiwei Wang Dr. Zhijun Huang Shuang Liu Juan Guo Fengrong Zhang Hongjun Yuan Xin Li Prof. Fengyong Liu Prof. Huiyu Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(32):13659-13663
The high reactive oxygen species (ROS) generation ability and simple construction of sonosensitizer systems remain challenging in sonodynamic therapy against the hypoxic tumor. In this work, we rationally prepared MOF-derived double-layer hollow manganese silicate nanoparticle (DHMS) with highly effective ROS yield under ultrasound irradiation for multimodal imaging-guided sonodynamic therapy (SDT). The presence of Mn in DHMS increased ROS generation efficiency because it could be oxidized by holes to improve the electron–hole separation. Moreover, DHMS could produce oxygen in the tumor microenvironment, which helps overcome the hypoxia of the solid tumor and thus enhance the treatment efficiency. In vivo experiments demonstrated efficient tumor inhibition in DHMS-mediated SDT guided by ultrasound and magnetic resonance imaging. This work presents a MOF-derived nanoparticle with sonosensitive and oxygen generating ability, which provides a promising strategy for tumor hypoxia in SDT. 相似文献
999.
Dr. Hua Su Ben Niu Haoran Li Dr. Fei Liu Tinglian Yuan Prof. Hong-Yuan Chen Prof. Wei Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(43):19371-19376
The ordered assembly of molecules within a specific space of nanoscale, such as a surface, holds great promise in advanced micro-/nanostructure fabrication for various applications. Herein, we demonstrate the evanescent wave (EW)-guided organization of small molecules into a long-range ordered nanowire (NW) array. Experiment and simulation revealed that the orientation and periodicity of the NW array were feasibly regulated by altering the propagation direction and the wavelength of EW. The generality of this approach was demonstrated by using different molecule precursors. While existing studies on EW often took advantages of its near-field property for optical sensing, this work demonstrated the photochemical power of EW in the guided-assembly of small molecules for the first time. It also provides an enlightening avenue to periodic structure with fluorescence, promising for super-resolution microscopy and important devices applicable to optical and bio-related fields. 相似文献
1000.
Dr. Yan-Xia Zhao Dr. Bin Yang Dr. Hai-Fang Li Yan Zhang Yuan Yang Dr. Qing-Yu Liu Dr. Hong-Guang Xu Prof. Wei-Jun Zheng Prof. Sheng-Gui He 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(47):21402-21409
Photoassisted steam reforming and dry (CO2) reforming of methane (SRM and DRM) at room temperature with high syngas selectivity have been achieved in the gas-phase catalysis for the first time. The catalysts used are bimetallic rhodium–vanadium oxide cluster anions of Rh2VO1–3−. Both the oxidation of methane and reduction of H2O/CO2 can take place efficiently in the dark while the pivotal step to govern syngas selectivity is photo-excitation of the reaction intermediates Rh2VO2,3CH2− to specific electronically excited states that can selectively produce CO and H2. Electronic excitation over Rh2VO2,3CH2− to control the syngas selectivity is further confirmed from the comparison with the thermal excitation of Rh2VO2,3CH2−, which leads to diversity of products. The atomic-level mechanism obtained from the well-controlled cluster reactions provides insight into the process of selective syngas production from the photocatalytic SRM and DRM reactions over supported metal oxide catalysts. 相似文献