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101.
陈向娟  王欢  安伟佳  刘利  崔文权 《化学进展》2022,34(11):2361-2372
有机碳材料因电荷传导效率高、结构可调、无污染等特点被广泛应用于光电催化领域。将含有机碳材料的催化剂作为电极材料已成为光电催化领域的研究热点之一。本文介绍了几种常见的有机碳材料的结构、特点、制备方法及其研究方向,并将含有机碳材料的电极进行分类。主要总结并论述了有机碳材料在光电催化系统中的五种作用:(1)作为催化剂;(2)作为光敏剂(3)作为电子介质;(4)作为催化剂载体;(5)作为光电极的稳定剂,最后阐述了有机碳材料在光电催化系统中的研究现状及难点问题。  相似文献   
102.
Nitrogen transfer from cyanide anion to an aldehyde is emerging as a promising method for the synthesis of aromatic nitriles. However, this method still suffers from a disadvantage that a use of stoichiometric Cu(II) or Cu(I) salts is required to enable the reaction. As we report herein, we overcame this drawback and developed a catalytic method for nitrogen transfer from cyanide anion to an alcohol via the complete cleavage of the C≡N triple bond using phen/Cu2O as the catalyst. The present condition allowed a series of benzyl alcohols to be smoothly converted into aromatic nitriles in moderate to high yields. In addition, the present method could be extended to the conversion of cinnamic alcohol to 3-phenylacrylonitrile.  相似文献   
103.
This study established a ferric ion (Fe3+) detection method as a result of the fluorescence quenching effect of Fe3+ on carbon dots (CDs). Specifically, we proposed, a green microwave synthesis route towards fluorescent CDs that requires only the brewer’s spent grain as starting materials. Transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectra and X-ray photoelectron spectroscopy were performed to investigate the CDs characteristic: morphology, size distribution, functional groups, and composition, respectively. The experimental results, which were run under optimal experimental conditions, indicated that the fluorescence intensity and concentration of Fe3+ were within the desired linear range (0.3–7 μM). The detection limit of this assay towards Fe3+ was 95 nM. The proposed method showed significant selectivity with respect to interfering ions. We evaluated the potential application of this method with tap water, lake water and fetal bovine serum as real samples. Additionally, the CDs could be served as superior bioimaging probes in Hela cells as a result of their excellent optical stability and good biocompatibility. In a word, the present study provides a new idea for CDs derived from the waste of agricultural products for detecting food or environmental contaminants and cell imaging.  相似文献   
104.
This study identified the isoindolone ring as a scaffold for novel agents against Trypanosoma brucei rhodesiense and explored the structure-activity relationships of various aromatic ring substitutions. The compounds were evaluated in an integrated in vitro screen. Eight compounds exhibited selective activity against T. b. rhodesiense (IC50<2.2 μm ) with no detectable side activity against T. cruzi and Leishmania infantum. Compound 20 showed low nanomolar potency against T. b. rhodesiense (IC50=40 nm ) and no toxicity against MRC-5 and PMM cell lines and may be regarded as a new lead template for agents against T. b. rhodesiense. The isoindolone-based compounds have the potential to progress into lead optimization in view of their highly selective in vitro potency, absence of cytotoxicity and acceptable metabolic stability. However, the solubility of the compounds represents a limiting factor that should be addressed to improve the physicochemical properties that are required to proceed further in the development of in vivo-active derivatives.  相似文献   
105.
A microwave electrically tunable photonic crystal based on a periodically width-modulated slot transmission line with a ferroelectric film is investigated for the first time. The dispersion and transmission characteristics of electromagnetic waves propagating in such a structure are calculated. The electric control over photonic crystal characteristics is simulated.  相似文献   
106.
WeiPing Liu  ZhiHong Li  JiangJun He  XiaoDong Tang  Gang Lian  Zhu An  JianJun Chang  Han Chen  QingHao Chen  XiongJun Chen  ZhiJun Chen  BaoQun Cui  XianChao Du  ChangBo Fu  Lin Gan  Bing Guo  GuoZhu He  Alexander Heger  SuQing Hou  HanXiong Huang  Ning Huang  BaoLu Jia  LiYang Jiang  Shigeru Kubono  JianMin Li  KuoAng Li  Tao Li  YunJu Li  Maria Lugaro  XiaoBing Luo  HongYi Ma  ShaoBo Ma  DongMing Mei  YongZhong Qian  JiuChang Qin  Jie Ren  YangPing Shen  Jun Su  LiangTing Sun  WanPeng Tan  Isao Tanihata  Shuo Wang  Peng Wang  YouBao Wang  Qi Wu  ShiWei Xu  ShengQuan Yan  LiTao Yang  Yao Yang  XiangQing Yu  Qian Yue  Sheng Zeng  HuanYu Zhang  Hui Zhang  LiYong Zhang  NingTao Zhang  QiWei Zhang  Tao Zhang  XiaoPeng Zhang  XueZhen Zhang  ZiMing Zhang  Wei Zhao  Zuo Zhao  Chao Zhou  JUNA Collaboration 《中国科学:物理学 力学 天文学(英文版)》2016,59(4):642001
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of~(25)Mg(p,γ)~(26)Al,~(19)F(p,α)~(16)O,~(13)C(α,n)~(16)O and ~(12)C(α,γ)~(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.  相似文献   
107.
The coupling of aryldiazonium tetrafluoroborates, DABCO?(SO2)2, and hydrazines under metal‐free conditions leads to the formation of aryl N‐aminosulfonamides. The reaction proceeds smoothly at room temperature and shows broad functional‐group tolerance. A radical process is proposed for this transformation.  相似文献   
108.
Assisted by graphene oxide(GO),nano-sized LiMn0.6Fe0.4PO4 with excellent electrochemical performance was prepared by a facile hydrothermal method as cathode material for lithium ion battery.SEM and TEM images indicate that the particle size of LiMn0.6Fe0.4PO4(S2)was about 80 nm in diameter.The discharge capacity of LiMn0.6Fe0.4PO4 nanoparticles was 140.3 mAh-g^1 in the first cycle.It showed that graphene oxide was able to restrict the growth of LiMn0.6Fe0.4PO4 and it in situ reduction of GO could improve the electrical conductivity of LiMn0.6Fe0.4PO4 material.  相似文献   
109.
Two new iridium(III) complexes containing benzothiazol-2-yl carbazole derivative as a cyclometalated ligand (L) and picolinate (pic) or acetylacetonate (acac) as the ancillary ligand, Ir(III) bis(3-(benzothiazol-2-yl)-9-butyl-carbazole)(picolinate) [Ir(L)2(pic)] and Ir(III) bis(3-(benzothiazol-2-yl)-9-butyl-carbazole)(acetylacetonate) [Ir(L)2(acac)], were synthesized and characterized by elemental analysis, 1H NMR, FT-IR, and UV–Vis absorption spectra. Both the iridium(III) complexes emit intense green–yellow emissions, indicating that they are useful for the fabrication of organic light-emitting diodes.  相似文献   
110.
Stimuli-responsive smart photosensitizer (PS) nanoassemblies that allow enhanced delivery and controlled release of PSs are promising for imaging-guided photodynamic therapy (PDT) of tumors. However, the lack of high-sensitivity and spatial-resolution signals and fast washout of released PSs from tumor tissues have impeded PDT efficacy in vivo. Herein, we report tumor targeting, redox-responsive magnetic and fluorogenic PS nanoassemblies ( NP-RGD ) synthesized via self-assembly of a cRGD- and disulfide-containing fluorogenic and paramagnetic small molecule ( 1-RGD ) for fluorescence/magnetic resonance bimodal imaging-guided tumor PDT. NP-RGD show high r1 relaxivity but quenched fluorescence and PDT activity; disulfide reduction by glutathione (GSH) promotes efficient disassembly into a small-molecule probe ( 2-RGD ) and an organic PS (PPa-SH), which could further bind with intracellular albumin, allowing prolonged retention and cascade activation of fluorescence and PDT to ablate tumors.  相似文献   
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