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101.
Liming Fan Feng Wang Dongsheng Zhao Yuxin Peng Yuxin Deng Yinwei Luo Xiutang Zhang 《应用有机金属化学》2020,34(12):e5960
Guided by the self-penetrating features can improve the stability of metal organic frameworks (MOFs), an unprecedented 3D self-penetrated framework, {[Zn (tptc)0.5(bimb)]·H2O}n ( NUC-6 , here NUC corresponding to North University of China), with 3D (4,4)-c {86} net, was designed. Benefit from the high chemical stability and excellent luminescent property, NUC-6 can be act as an efficient multi-response chemo-sensor in detecting dichloronitroaniline pesticide and nitrofuran antibiotics in water with the detection limits are 116 ppb for DCN pesticide, 16 ppb for NFT antibiotic, and 12 ppb for NTZ antibiotic. Besides, the mechanisms of luminescence quenching were revealed from the viewpoint of internal filter effect (IFE) and photo-induced electron transfer (PET), implied by the optical spectroscopy and quantum chemical calculation. This work provides a promising strategy to design stable MOFs by improving the self-penetrating features and to expand their practical applications in the detection of organic pollutants in aqueous medium. 相似文献
102.
Wenqing Zhang Dr. Jiuxing Li Prof. Dr. Bruno Salena Prof. Dr. Yingfu Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(3):592-596
DNA detection is usually conducted under nondenaturing conditions to favor the formation of Watson–Crick base-paring interactions. However, although such a setting is excellent for distinguishing a single-nucleotide polymorphism (SNP) within short DNA sequences (15–25 nucleotides), it does not offer a good solution to SNP detection within much longer sequences. Here we report on a new detection method capable of detecting SNP in a DNA sequence containing 35–90 nucleotides. This is achieved through incorporating into the recognition DNA sequence a previously discovered DNA molecule that forms a stable G-quadruplex in the presence of 7 molar urea, a known condition for denaturing DNA structures. The systems are configured to produce both colorimetric and fluorescent signals upon target binding. 相似文献
103.
Dr. Jun Zeng Dr. Zhichao Wang Dr. Xin Huang Dr. Sabine S. Eckstein Prof. Dr. Xiaohui Lin Prof. Dr. Hailong Piao Prof. Dr. Cora Weigert Dr. Peiyuan Yin Prof. Dr. Rainer Lehmann Prof. Dr. Guowang Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(21):5427-5432
Mass spectrometry (MS) driven metabolomics is a frequently used tool in various areas of life sciences; however, the analysis of polar metabolites is less commonly included. In general, metabolomic analyses lead to the detection of the total amount of all covered metabolites. This is currently a major limitation with respect to metabolites showing high turnover rates, but no changes in their concentration. Such metabolites and pathways could be crucial metabolic nodes (e.g., potential drug targets in cancer metabolism). A stable-isotope tracing capillary electrophoresis–mass spectrometry (CE-MS) metabolomic approach was developed to cover both polar metabolites and isotopologues in a non-targeted way. An in-house developed software enables high throughput processing of complex multidimensional data. The practicability is demonstrated analyzing [U-13C]-glucose exposed prostate cancer and non-cancer cells. This CE-MS-driven analytical strategy complements polar metabolite profiles through isotopologue labeling patterns, thereby improving not only the metabolomic coverage, but also the understanding of metabolism. 相似文献
104.
Dr. Takeshi Nanjo Natsuki Kato Xuan Zhang Prof. Yoshiji Takemoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(68):15504-15507
Strategies for the formation of amide bonds, that is, one of the most basic and important transformations in organic synthesis, have so far focused predominantly on dehydration reactions. Herein, we report and demonstrate the practical utility of a novel decarboxylative amidation of α-ketoacids by using inexpensive tert-butyl hydroperoxide (TBHP), which is characterized by high yields, a broad substrate scope, mild reaction conditions, and a unique chemoselectivity. These features enable the synthesis of peptides from amino acid derived α-ketoacids under preservation of the stereochemical information. 相似文献
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106.
In this paper, we propose a sufficient and necessary condition for the boundedness of all the solutions for the equation with the critical situation that on g and p, where , is periodic and is bounded. 相似文献
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In this Letter,a novel system for adaptively correcting the phase of a dynamic multimode beam is proposed.While using merely one spatial light modulator,the phase measurement of the first-order diffraction pattern and the correction of the zeroth diffraction order are simultaneously realized.The real-time experimental result is obtained at a control rate of 10 Hz.The power-in-the-bucket value is improved from 38.5%to 61.8%,even with fundamental mode content that is consistently below 30%.To the best of our knowledge,this is the first implementation of real-time adaptive correction of the entire multimode beam. 相似文献