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991.
Weinan Xing Shengming Yin Wenguang Tu Guanyu Liu Shuyang Wu Haojing Wang Markus Kraft Guangyu Wu Rong Xu 《Angewandte Chemie (International ed. in English)》2020,59(3):1171-1175
A simple solvent ligation effect was successfully used to disrupt the growth of a model compound, Fe[(OH)(O3P(CH2)2CO2H)]?H2O (MIL‐37), into an extended 2D structure by replacing water with dimethylformamide (DMF) as the solvent during the synthesis. Owing to the lack of ?OH group, which provides the corner‐sharing (binding) oxygen atoms for the octahedra, an amorphous and porous structure is formed. When Fe3+ is partially replaced by Ni2+, the amorphous structure remains and the resultant binary metal catalyst displays excellent photocatalytic oxygen evolution activity with almost 100 % yield achieved under visible light irradiation using [Ru(bpy)3]2+ as the photosensitizer. This study opens up new possibilities of using the simple solvent effect to synthesize high surface area metal phosphonates for catalytic and other applications. 相似文献
992.
Min Bai Feng Chen Xiaowen Cao Yue Zhao Jing Xue Xu Yu Chunhai Fan Yongxi Zhao 《Angewandte Chemie (International ed. in English)》2020,59(32):13267-13272
Tumor progressions such as metastasis are complicated events that involve abnormal expression of different miRNAs and enzymes. Monitoring these biomolecules in live cells with computational DNA nanotechnology may enable discrimination of tumor progression via digital outputs. Herein, we report intracellular entropy‐driven multivalent DNA circuits to implement multi‐bit computing for simultaneous analysis of intracellular telomerase and microRNAs including miR‐21 and miR‐31. These three biomolecules can trigger respective DNA strand displacement recycling reactions for signal amplification. They are visualized by fluorescence imaging, and their signal outputs are encoded as multi‐bit binary codes for different cell types. The results can discriminate non‐tumorigenic, malignant and metastatic breast cells as well as respective tumors. This DNA computing circuit is further performed in a microfluidic chip to differentiate rare co‐cultured cells, which holds a potential for the analysis of clinical samples. 相似文献
993.
Pengfei Xia Shaowen Cao Bicheng Zhu Mingjin Liu Miusi Shi Jiaguo Yu Yufeng Zhang 《Angewandte Chemie (International ed. in English)》2020,59(13):5218-5225
Constructing heterojunctions between two semiconductors with matched band structure is an effective strategy to acquire high‐efficiency photocatalysts. The S‐scheme heterojunction system has shown great potential in facilitating separation and transfer of photogenerated carriers, as well as acquiring strong photoredox ability. Herein, a 0D/2D S‐Scheme heterojunction material involving CeO2 quantum dots and polymeric carbon nitride (CeO2/PCN) is designed and constructed by in situ wet chemistry with subsequent heat treatment. This S‐scheme heterojunction material shows high‐efficiency photocatalytic sterilization rate (88.1 %) towards Staphylococcus aureus (S. aureus) under visible‐light irradiation (λ≥420 nm), which is 2.7 and 8.2 times that of pure CeO2 (32.2 %) and PCN (10.7 %), respectively. Strong evidence of S‐scheme charge transfer path is verified by theoretical calculations, in situ irradiated X‐ray photoelectron spectroscopy, and electron paramagnetic resonance. 相似文献
994.
Shufang Ji Yang Qu Tao Wang Yuanjun Chen Guofeng Wang Xue Li Juncai Dong QiuYu Chen Wanying Zhang Zedong Zhang Shiyou Liang Rong Yu Yu Wang Dingsheng Wang Yadong Li 《Angewandte Chemie (International ed. in English)》2020,59(26):10651-10657
The solar‐driven photocatalytic reduction of CO2 (CO2RR) into chemical fuels is a promising route to enrich energy supplies and mitigate CO2 emissions. However, low catalytic efficiency and poor selectivity, especially in a pure‐water system, hinder the development of photocatalytic CO2RR owing to the lack of effective catalysts. Herein, we report a novel atom‐confinement and coordination (ACC) strategy to achieve the synthesis of rare‐earth single erbium (Er) atoms supported on carbon nitride nanotubes (Er1/CN‐NT) with a tunable dispersion density of single atoms. Er1/CN‐NT is a highly efficient and robust photocatalyst that exhibits outstanding CO2RR performance in a pure‐water system. Experimental results and density functional theory calculations reveal the crucial role of single Er atoms in promoting photocatalytic CO2RR. 相似文献
995.
Qian Wei Rong Zhang Qin Wang Xin Jia Yan Quan Wei Yu Fu Xia Yan 《Natural product research》2020,34(9):1320-1325
AbstractAs part of our continuing efforts to explore bioactive compounds from natural resources, a new iridoid glycoside, adoxosidic acid-6′-oleuroperic ester (1), together with one known phenylethanoid glycoside (2) and two known flavonoid glycosides (3–4) were isolated from the fruit of Forsythia suspensa. The structure of the new compound (1) was elucidated through 1D and 2D NMR spectroscopic data and HR-ESIMS. Interestingly, compound 1 was a monoterpene ester of one iridoid glycoside. Compounds 2–4 were identified as calceolarioside A (2), kaempferol-3-O-rutinoside (3), kampferol-3-O-robinobioside (4) on the basis of NMR spectroscopic data analyses and comparison with the data reported in the literature. The antiviral activity aganisist influenza A (H5N1) virus of compound 1 was studied as well. 相似文献
996.
Xuemin Ye Beibei Ye Jiahui Xu Mei Fang Danqi Dong Congcong Wu Xupin Lin Yehui Hu Xiaoji Cao Weimin Mo 《Journal of separation science》2020,43(17):3546-3554
In this work, a novel quick, easy, cheap, effective, rugged, and safe technique with hydrophobic natural deep eutectic solvent as both extractant and analyte protectant was developed and combined with gas chromatography–tandem mass spectrometry to analyze pyrethroid residues in tomatoes. Eight hydrophobic natural deep eutectic solvents were first evaluated as analyte protectants and those with decanoic acid or lactic acid as hydrogen bond donor were demonstrated to be effective in compensating for the matrix effects of pyrethroids in the gas chromatography system. Hence, they were added to solvent standards for correcting the quantitation errors instead of matrix‐matched calibration standards. Then the abilities of these acid‐based deep eutectic solvents to extract pyrethriods from tomatoes were evaluated. Results showed the recoveries of all pyrethroids reached to over 80% with only 5 mL menthol:decanoic acid (1:1) used, and good phase separation was easily achieved without the addition of inorganic salt in the extraction step, indicating hydrophobic natural deep eutectic solvent could be a green substitute for acetonitrile in the quick, easy, cheap, effective, rugged, and safe extraction. Compared with the conventional method, the proposed protocol improved the recoveries, reduced the matrix effects, and simplified the extraction step, demonstrating to be an effective, fast, and green method. 相似文献
997.
Xiaoya Yu Linzhong Wu Di Yang Muhan Cao Xing Fan Haiping Lin Qixuan Zhong Yong Xu Qiao Zhang 《Angewandte Chemie (International ed. in English)》2020,59(34):14527-14532
Hydrochromic materials that can reversibly change color upon water treatment have attracted much attention owing to their potential applications in diverse fields. Herein, for the first time, we report that space‐confined CsPbBr3 nanocrystals (NCs) are hydrochromic. When CsPbBr3 NCs are loaded into a porous matrix, reversible transition between luminescent CsPbBr3 and non‐luminescent CsPb2Br5 can be achieved upon the exposure/removal of water. The potential applications of hydrochromic CsPbBr3 NCs in anti‐counterfeiting are demonstrated by using CsPbBr3 NCs@mesoporous silica nanospheres (around 100 nm) as the starting material. Owing to the small particle size and negatively charged surface, the as‐prepared particles can be laser‐jet printed with high precision and high speed. We demonstrate the excellent stability over repeated transformation cycles without color fade. This new discovery may not only deepen the understanding of CsPbX3, but also open a new way to design CsPbX3 materials for new applications. 相似文献
998.
Shan-Shan Guo Xue Pang Yang Wang Zhu-Feng Geng Ju-Qin Cao Jun-Yu Liang 《Natural product research》2020,34(18):2595-2601
AbstractOne new sesquiterpene (α-iso-cubebenol acetate, 8), together with 9 known compounds (1-7, 9, 10) were isolated from the stems of Schisandra chinensis (Turcz.) Baill. by repeated silica gel column chromatography. Based on the results of MS, NMR spectra and comparing with literature data, the six dibenzocyclooctadiene lignans were identified as schizandrin A to C (1-3), schizandrin (4), schisantherin A (5) and gomisin J (6), the two sesquiterpenes were identified as α-iso-cubebenol (7) and α-iso-cubebenol acetate (8), while the two triterpenic acids were identified as ganwuweizic acid (9) and kadsuric acid (10). The antifeedant activity of the 10 compounds against Tribolium castaneum adults was tested. Gomisin J (6) exhibited activity at 1500?ppm concentration with 40.3% antifeeding index percentages. As for the dibenzocyclooctene lignans (compounds 1–3, 6), the number of methylenedioxies and the position of hydroxyl groups were the main factors to affect their antifeedant activities. 相似文献
999.
Rong Wang Fu-Qiang Ni Jun Sang Yao Zhang Jia-Luo Huang Sheng Yin 《Natural product research》2020,34(7):935-942
AbstractPhytochemical investigation on the leaves and twigs of Toona ciliata has led to the isolation of four new polyynes (1–4) and two knowns (5 and 6). Their structures were determined by extensive spectroscopic analysis (MS, UV, IR, and NMR) and Mosher’s method. All compounds were evaluated for their inhibitory activities against HepG2 human tumor cell line but were inactive. 相似文献
1000.
AbstractThe study on inhibitory effects of resveratrol glucosides (REs) on advanced glycation endproducts (AGEs) formation is still unmet. Herein, for the first time, the antiglycation activities of five REs in the fetal bovine serum proteins (FBS)/fructose system were evaluated, and its structure-activity relationship and antiglycation mechanism were further explored. These REs showed remarkable inhibition toward AGEs formation. Among them, Piceatannol-3'-O-glucoside (PG) exhibited highest antiglycation activity as reflected in approximately 80% inhibition of fluorescent AGEs at the concentration of 1.0?mM. The structure-activity relationship analysis indicated that glucoside attached to the B ring of resveratrol displays a superior antiglycation activity. Moreover, the results of antiglycation mechanism showed that the antiglycation activity of REs was proportional to their antioxidant capacity and methylglyoxal (MGO) trapping capacity. Therefore, the REs are promising candidates worthy of further exploration for preventing AGEs accumulation in vivo, thereby treating AGEs-associated diseases. 相似文献