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141.
Yanfeng Liu Xin Huang Zuoji Niu Dongni Wang Huilin Gou Qiaobo Liao Kai Xi Zhongfu An Xudong Jia 《Chemical science》2021,12(23):8199
Stimuli-responsive films with a dynamic long afterglow feature have received considerable attention in the field of optical materials. Herein, we report the unique dynamic ultralong room temperature phosphorescence (URTP) in flexible solid films made of luminescent carbon dots (CDs) and polyvinylpyrrolidone (PVP). Impressively, fully reversible photo-activation and thermal deactivation of the dynamic long afterglow was achieved in this material, with a lifetime on–off ratio exceeding 3900. Subsequently, ultra-fine URTP patterns (resolution > 1280 dpi) with thermally sensitive retention time were readily photo-printed onto the films and utilized as time–temperature indicating logistics labels with multi-editing capacity. These findings not only enrich the library of dynamic URTP materials, but also extend the scope of the potential applications of luminescent CDs.A flexible CD–polymer composite with a reversibly editable photo-induced URTP long afterglow was rationally designed and successfully applied in dynamic optical patterning with built-in time–temperature indicating functionality. 相似文献
142.
Su Xudong Feng Meng Rogers Shane Holsen Thomas M. Thagard Selma Mededovic 《Plasma Chemistry and Plasma Processing》2019,39(3):577-596
Plasma Chemistry and Plasma Processing - This work investigates the effect of high voltage (HV) electrode material of a point-plane plasma reactor on the inactivation rate of E. coli in both direct... 相似文献
143.
JuanJuan Li Zhenzhen Tian Shumiao Zhang Zhishan Xu Xudong Mao Yumin Zhou Zhe Liu 《应用有机金属化学》2019,33(4)
The use of metal complexes containing phosphorus ligands as anticancer agents has not been well studied. In this work, eight novel half‐sandwich IrIII and RuII compounds with P^P‐chelating ligands have been synthesized and fully characterized, and alongside two crystal structures were reported. All eight complexes displayed highly potent antiproliferative activity, up to nine times more potent than the clinical anticancer drug cisplatin towards A549 lung cancer cells. Complex Ir1 , which has a simpler structure and highly potent antiproliferative activity, was selected to investigate in further mechanistic studies. No hydrolysis and nucleobase binding occurred for complex Ir1 . In order to elucidate subcellular localization, the self‐luminescence of the complex Ir1 was utilized. Ir1 can specifically target lysosomes and facilitate excessive production of reactive oxygen species, resulting in lysosomal membrane permeabilization in A549 cells. Release of cathepsin B and changes in the mitochondria membrane potential also contributed to the observed cytotoxicity of Ir1 , which demonstrated an anticancer action mechanism that was different from that of cisplatin. The favorable results from biological and chemical research demonstrated that these types of complexes hold significant theranostic potential. 相似文献
144.
Journal of Algebraic Combinatorics - We call a finite, spanning set of a semi-simple real Lie algebra a distinguished set if it satisfies the following property: The Lie bracket of any two elements... 相似文献
145.
Xudong Hou Giang Truong Nguyen Tingting Xu Dr. Haipeng Wei Dr. Tun Seng Herng Dr. Guifei Huo Dr. Dingguan Wang Prof. Jun Ding Dr. Shaofei Wu Prof. Liviu Ungur Prof. Jishan Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(31):e202200687
The incorporation of organic radicals into coordination polymers was considered as a promising strategy to promote metal-ligand exchange interactions, but there are only a very limited number of stable organic radical-based ligands that can serve well such a purpose. Herein, we report two new tris(2,4,6-trichlorophenyl)methyl (TTM) radical-based ligands L1 and L2 with two and three imidazole substituents, respectively. The imidazole unit serves as a coordination site and it can also stabilize the TTM radical by intramolecular donor–acceptor interaction. Coordination of L1 and L2 with cobalt(II) ions gave the corresponding one- ( CoCP - 1 ) and two-dimensional ( CoCP - 2 ) coordination polymers, the structures of which were confirmed by X-ray crystallographic analysis. Magnetic measurements and theoretical calculations suggest antiferromagnetic coupling between the paramagnetic cobalt(II) ions and the radical ligands. Our study provides a rational design for stable organic radical-based ligands and further demonstrated the feasibility of a metal–radical approach toward magnetic materials. 相似文献
146.
Research on Chemical Intermediates - In this paper, a new ferrocenylimidazole compound L was designed and synthesized. L could selectively sense a fluoride anion among test anions such as F?,... 相似文献
147.
148.
The extraction of uranium from aqueous solution is highly desirable for sustaining the increasing demand for environmental safety and nuclear fuel. Herein, we report a strategy using a two-step covalent modification for the synthesis of covalent organic frameworks(COFs) with high-density amidoxime chelate groups at periphery. The introduction of dense amidoxime groups plays a pivotal role in uranium adsorption. The resulting COF exhibits strong affinity with the distribution coefficient of 5.2×104 mL/g and a high adsorption capacity of 319.9 mg/g. The strategy could be expanded to identify and remove different contaminants by introducing special functional groups. 相似文献
149.
Docetaxel‐Loaded Nanoparticles of Dendritic Amphiphilic Block Copolymer H40‐PLA‐b‐TPGS for Cancer Treatment
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Xiaowei Zeng Wei Tao Zhongyuan Wang Xudong Zhang Huijun Zhu Yanping Wu Yongfeng Gao Kewei Liu Yuyang Jiang Laiqiang Huang Lin Mei Si‐Shen Feng 《Particle & Particle Systems Characterization》2015,32(1):112-122
A dendritic amphiphilic block copolymer H40‐poly(d,l ‐lactide)‐block‐d‐α‐tocopheryl polyethylene glycol 1000 succinate (H40‐PLA‐b‐TPGS) is synthesized, which is then employed to develop a system of nanoparticles (NPs) loaded with docetaxel (DTX) as a model drug for cancer treatment due to its higher drug‐loading content and drug encapsulation efficiency, smaller particle size, faster drug release, and higher cellular uptake in comparison to the linear PLA polymer NPs and PLA‐b‐TPGS copolymer NPs. The drug‐loaded NPs are prepared by a modified nanoprecipitation method and characterized in terms of size and size distribution, surface morphology, drug release profile, and physical state of DTX. Cellular uptake of coumarin 6‐loaded NPs by MCF‐7 cancer cells is determined by flow cytometry and confocal laser scanning microscopy. The antitumor efficacy of the drug‐loaded NPs is investigated in vitro by MTT assay and in vivo by xenograft tumor model. The 72 h IC50 of the drug formulated in the PLA, PLA‐b‐TPGS, and H40‐PLA‐b‐TPGS NPs is found to be, 1.5 ± 0.3, 0.9 ± 0.1, and 0.15 ± 0.06 μg mL?1, which are 7.3, 12.2, and 73.3‐fold effective than 11.0 ± 1.2 μg mL?1 for Taxotere, respectively. Such advantages are further confirmed by the measurement of the tumor size and weight. 相似文献
150.
Yuzhao Yang Lu Sun Jiemei Ou Yiting He Xiaofeng Lin Zhongke Yuan Wensheng Lin Wei Hong Dingshan Yu Xudong Chen Zhiren Qiu 《Journal of Raman spectroscopy : JRS》2016,47(8):888-894
There is no consensus yet that the enhancement effects of plasmonic device are predominantly caused by plasmonic effects or induced morphology changes in the optoelectronic `materials. Herein, we present a detailed Raman characterization of a typical organic P3HT:PCBM system comprising silver nanowires (Ag NWs) with different size, which can simultaneously study the plasmonic effects and the morphology changes. The direct comparison of the Raman spectra of non‐annealed and annealed samples indicates that the morphology of plasmonic samples has changed before annealing and the morphology of plasmonic samples and reference sample after annealing is not distinguishable. This indicates that the interaction between P3HT and Ag NWs with different size can be explained by plasmonic effects after annealing. Moreover, in‐situ Raman spectroscopy is used to study the morphology changes in plasmonic samples with different diameters of Ag NWs during heating process. This method can distinguish the plasmonic effects and morphology changes of plasmonic device. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献