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951.
Liu Shanshan Liu Xiujing Wang Qiang Wang Yingchao Ji Xingxiang Yang Guihua Chen Jiachuan Ni Yonghao 《Cellulose (London, England)》2022,29(3):1993-2003
Cellulose - Superhydrophobic and strong cellulosic paper was fabricated in a two-step process consisting of heavy refining and dip coating with PDMS (trimethylsiloxy-terminated poly... 相似文献
952.
NIR-II Fluorescent Brightness Promoted by “Ring Fusion” for the Detection of Intestinal Inflammation
Yaxi Li Menglei Zha Dr. Guang Yang Shuxian Wang Prof. Jen-Shyang Ni Prof. Kai Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(51):13085-13091
Fluorophores with emission in the second near-infrared window (NIR-II) have displayed salient advantages for biomedical applications. However, the common strategy of reducing the energy bandgap of fluorophores so as to achieve red-shifted wavelengths always leads to compromised fluorescent brightness. Herein, we propose a molecular design concept of “ring-fusion” to modify the acceptor of AIEgen that can extend the luminous wavelength from NIR-I to NIR-II. The fused-acceptor-containing fluorophore yielded, TTQP, has an enhanced absorption coefficient with a higher brightness in nanoparticle formation compared to its NIR-I emissive counterpart (TTQ-DP) with a non-fused acceptor. Theoretical calculation further confirms that the ring fusion can efficiently promote the rigidity and planarity of the electron-deficient core, leading to a lower reorganization energy and nonradiative decay. The TTQP NPs yielded thus allow sensitive NIR-II fluorescence imaging of vasculature and intestinal inflammation in mice models. Therefore, we anticipate that our work will provide a promising molecular-engineering strategy to enrich the library and broaden the application scope of NIR-II fluorophores. 相似文献
953.
Depei Meng Yichong Lyu Dr. Chuanfa Ni Dr. Min Zhou Prof. Dr. Yang Li Prof. Dr. Jinbo Hu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(13):e202104395
S-(Trifluoromethyl)benzothioate (TFBT) has been developed as an inexpensive, bench-stable, and user-friendly trifluoromethylthiolation reagent, which can be easily synthesized by using KF as the only fluorine source. By using TFBT, trifluoromethylthiolates with various counterions can be readily obtained. The synthetic application of TFBT was demonstrated by trifluoromethylthiolation-halogenation of arynes, bis(trifluoromethylthiolation)–halogenation of 1,2-benzdiynes, nucleophilic substitution of alkyl halides, deoxytrifluoromethylthiolation of alcohols, and cross-coupling with aryl and vinyl boronic acids. 相似文献
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This letter reports the application of the scanning heating laser source technique to detect microcracks that may be undetected by conventional methods.In the proposed approach,we monitor changes in the transmitted surface acoustic waves(SAWs) as a heating source is scanned over the crack.The experimental system for microcrack detection by a scanning heating laser source is obtained by exploiting the strong dependence of the transmission efficiency of acoustic pulses on the state of the contacts,whether open or closed,between the crack faces.Microcracks can be detected successfully by confirming the heating position at the point of maximal improvement of the transmission efficiency of the SAWs. 相似文献
957.
Wang Junru Zhou Yucheng Shao Yamin He Feng Wu Min Ni Henmei Zheng Yingping Sun Yueming 《Research on Chemical Intermediates》2019,45(4):1721-1735
Research on Chemical Intermediates - Hybrid materials of chitosan–silica (CS–SiO2) with nonprecious-metallic ions (Cu) immobilized on (Cu–M@CS–SiO2) were developed as green... 相似文献
958.
Jiao Bian Ying Hao Jinlin He Wenling Zhang Mingzu Zhang Peihong Ni 《Journal of polymer science. Part A, Polymer chemistry》2014,52(21):3005-3016
This study is aimed to develop a well‐defined ABC triblock terpolymer, poly(ethylethylene phosphate)‐block‐poly(ε‐caprolactone)‐block‐poly[2‐(dimethylamino)ethyl methacrylate] (PEEP‐b‐PCL‐b‐PDMAEMA), for co‐encapsulating anticancer drug doxorubicin (DOX) and DNA to form polyplexes. The terpolymer is first synthesized via a combination of ring‐opening polymerization and atom‐transfer radical polymerization techniques, and characterized by 1H NMR and gel permeation chromatography. Subsequently, the self‐assembly behavior of the terpolymer and the micelles loaded with DOX or DNA are investigated by dynamic light scattering, ζ potential, transmission electron microscopy, and gel retardation assay, respectively. In vitro release study reveals that much more DOX is released at pH 5.0 than that at pH 7.4 in the same period. The simultaneous delivery of DOX and green fluorescent protein (GFP)‐labeled DNA is studied by a fluorescence microscope and the results demonstrate that both drug and GFP–DNA can be efficiently delivered into HeLa cells. This system presents a practical and promising carrier for the co‐delivery of drugs and genes. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3005–3016 相似文献
959.
Qualitative analysis of chemical constituents in traditional Chinese medicine analogous formula cheng‐Qi decoctions by liquid chromatography–mass spectrometry
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Xuexun Wen Kedi Luo Shun Xiao Ni Ai Shufang Wang Xiaohui Fan 《Biomedical chromatography : BMC》2016,30(3):301-311
Cheng‐Qi decoctions (CQs), a group of analogous formulas, are well‐known traditional Chinese preparations used as purgative remedies to treat ‘internal heat’‐induced symptoms, which manifest as a bloated and painful abdomen, hard stools, fever and other clinical observations. In this study, HPLC‐ESI‐MS/MS and UPLC‐TOF‐MS were employed for separation and structural identification of constituents in CQs. As a result, a total of 90 compounds, including seven anthraquinones, 39 flavones, 21 glycosides, 11 stilbene glycosides, six organic acids, five coumarins and one lignans, were detected and tentatively identified in CQs extracts. The characterization results shed some light on the scientific foundation for clinical application of the CQ analogous formulas. Our results also indicate that the HPLC‐MS method is useful for the systemic identification of major constituents in traditional Chinese medicine formulas. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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