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381.
Congcong Pei Chao Liu You Wang Dan Cheng Rongxin Li Weikang Shu Chaoqi Zhang Wenli Hu Aihua Jin Yannan Yang Jingjing Wan 《Angewandte Chemie (International ed. in English)》2020,59(27):10831-10835
High‐throughput metabolic analysis is of significance in diagnostics, while tedious sample pretreatment has largely hindered its clinic application. Herein, we designed FeOOH@ZIF‐8 composites with enhanced ionization efficiency and size‐exclusion effect for laser desorption/ionization mass spectrometry (LDI‐MS)‐based metabolic diagnosis of gynecological cancers. The FeOOH@ZIF‐8‐assisted LDI‐MS achieved rapid, sensitive, and selective metabolic fingerprints of the native serum without any enrichment or purification. Further analysis of extracted serum metabolic fingerprints successfully discriminated patients with gynecological cancers (GCs) from healthy controls and also differentiated three major subtypes of GCs. Given the low cost, high‐throughput, and easy operation, our approach brings a new dimension to disease analysis and classification. 相似文献
382.
Dr. Chao Liu Dr. Jing Wang Prof. Jingjing Wan Dr. Yan Cheng Prof. Rong Huang Chaoqi Zhang Wenli Hu Dr. Guangfeng Wei Prof. Chengzhong Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(9):3659-3666
Amorphous metal–organic frameworks (aMOFs) are an emerging family of attractive materials with great application potential, however aMOFs are usually prepared under harsh conditions and aMOFs with complex compositions and structures are rarely reported. In this work, an aMOF-dominated nanocomposite (aMOF-NC) with both structural and compositional complexity has been synthesized using a facile approach. A ligand-competition amorphization mechanism is proposed based on experimental and density functional theory calculation results. The aMOF-NC possesses a core–shell nanorod@nanosheet architecture, including a Fe-rich Fe-Co-aMOF core and a Co-rich Fe-Co-aMOF shell in the core–shell structured nanorod, and amorphous Co(OH)2 nanosheets as the outer layer. Benefiting from the structural and compositional heterogeneity, the aMOF-NC demonstrates an excellent oxygen evolution reaction activity with a low overpotential of 249 mV at 10.0 mA cm−2 and Tafel slope of 39.5 mV dec−1. 相似文献
383.
Zhong Mo Xinrui Miao Lirong Liang Wenli Deng Baojun Li Dinghua Bao 《Applied Physics A: Materials Science & Processing》2013,111(4):1113-1117
Bi3.95Er0.05Ti3O12 (BErT) thin films were prepared on Pt/Ti/SiO2/Si and indium-tin-oxide (ITO)-coated glass substrates at room temperature by pulsed laser deposition. These thin films were amorphous with uniform thickness. Excellent dielectric characteristics have been confirmed. The amorphous BErT thin films deposited on the Pt/Ti/SiO2/Si and ITO-coated glass substrates exhibited almost the same dielectric constant of 52 with a low dielectric loss of less than 0.02 at 1 kHz. Meanwhile, the dielectric properties of the thin films had an excellent bias voltage stability and thermal stability. The amorphous BErT thin films might have potential applications in microelectronic and optoelectronic devices. 相似文献
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(±)-5-(10-Undecenethylamido)-acenaphthene was synthesized and successfully separated into enantiomers using chiral HPLC. The chemical structure of this compound was characterized by FT-IR, 1H NMR, MS spectra, and elemental analyses. 相似文献
386.
为“闪光二号”加速器研制了新的二极管系统, 其电子束能注量比原二极管系统大3倍多。该系统由带滑闪开关的二极管、漂移管、脉冲磁场和真空靶室等部分组成, 通过减小阴极直径、增大轴向磁场强度和磁透镜比,调节滑闪开关距离和预脉冲开关气压等技术措施, 使二极管具有高能注量电子束输出的稳定工作状态, 在Marx发生器充电电压70kV条件下,在距阴极22cm的靶上获得了总能量21.5kJ、束斑直径52mm和能注量1.01kJ/cm2的电子束输出。 相似文献
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390.
Zirong Deng Jing Liu Tong Li Huayue Li Zengzhi Liu Yujing Dong Wenli Li 《Angewandte Chemie (International ed. in English)》2021,60(1):153-158
As a unique structural moiety in natural products, cinnamoyl lipids (CLs), are proposed to be assembled by unusual type II polyketide synthases (PKSs). Herein, we demonstrate that the assembly of the CL compounds youssoufenes is accomplished by a PKS system that uniquely harbors three phylogenetically different ketosynthase/chain length factor (KS/CLF) complexes (YsfB/C, YsfD/E, and YsfJ/K). Through in vivo gene inactivation and in vitro reconstitution, as well as an intracellular tagged carrier‐protein tracking (ITCT) strategy developed in this study, we successfully elucidated the isomerase‐dependent ACP‐tethered polyunsaturated chain elongation process. The three KS/CLFs were revealed to modularly assemble different parts of the youssoufene skeleton, during which benzene ring closure happens right after the formation of an ACP‐tethered C18 polyene. Of note, the ITCT strategy could significantly contribute to the elucidation of other carrier‐protein‐dependent biosynthetic machineries. 相似文献