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991.
Chuan‐Hua Zhou Yun Shu Zheng‐Yuan Hong Prof. Dr. Dai‐Wen Pang Prof. Dr. Zhi‐Ling Zhang 《化学:亚洲杂志》2013,8(9):2220-2226
A novel electrochemical magnetoimmunosensor for fast and ultrasensitive detection of H9N2 avian influenza virus particles (H9N2 AIV) was designed based on the combination of high‐efficiency immunomagnetic separation, enzyme catalytic amplification, and the biotin–streptavidin system. The reusable, homemade magneto Au electrode (M‐AuE) was designed and used for the direct sensing. Immunocomplex‐coated magnetic beads (IMBs) were easily accumulated on the surface of the M‐AuE to obtain the catalytically reduced electrochemical signal of H2O2 after the immunoreaction. The transducer was regenerated through a simple washing procedure, which made it possible to detect all the samples on a single electrode with higher reproducibility. The magnetic‐bead‐based electrochemical immunosensor showed better analytical performance than the planar‐electrode‐based immunosensor with the same sandwich construction. Amounts as low as 10 pg mL?1 H9N2 AIV could be detected even in samples of chicken dung. This electrochemical magnetoimmunosensor not only provides a simple platform for the detection of the virus with high sensitivity, selectivity, and reproducibility but also shows great potential in the early diagnosis of diseases. 相似文献
992.
Shigang Chao Xinwei Lu Mengmeng Zhang Long Pang 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(2):879-885
Natural radioactivity of the commonly used building materials in Xining of China was measured using gamma-ray spectrometer system comprising a NaI(Tl) detector. Radioactivity concentrations of 226Ra, 232Th and 40K in the studied samples range from 11.6 to 120.6, 10.2 to 107.1 and 228.0 to 1,036.2 Bq kg?1, respectively. The concentrations for these natural radionuclides were compared with the reported data of other countries and the mean value for soil. Radium equivalent activity, indoor air absorbed dose rate, annual effective dose rate as well as external and internal hazard indices were calculated to assess radiological hazards for people living in dwelling made of the building materials. The radiological hazard assessment results show that the studied building materials, except for some aerated concrete block samples, are safe for use in construction of dwellings in the study area and do not pose any significant source of radiation hazard. 相似文献
993.
Kaiqi Ge Changsheng Cao Gang Liu Yuling Li Juan Zhang Guangsheng Pang Yanhui Shi 《无机化学与普通化学杂志》2014,640(2):444-450
A series of [PdPyCl2]2(di‐NHC) complexes were prepared (di‐NHC are two 1‐(2,6‐dimethylphenyl)imidazolidene molecules bridged by an aliphatic –(CH2)n– linker (n = 3, 4, 5, 6, and 10)). All complexes were fully characterized by NMR spectroscopy and elemental analyses. The crystal structures of four complexes (n = 3, 4, 5 and 6) were determined by X‐ray diffraction. The influence of the distant methyl group on the structural features and catalytic activity with increasing of length of linker was investigated by comparing the results of these 2,6‐dimethylphenyl palladium complexes with those of their known mesityl analogues. X‐ray studies show the distant methyl substitution has big impact on the structure feature of the complexes with the shorter linker between two NHC (ethylene and propylene), but has a little or no effect on that of the complexes with longer linker (butylene and hexylene). Catalytic results of the arylation of styrene show that the remote substitute has big effect on the regioselectivity of the product in all complexes with shorter and longer linkers, but has a limited effect on the yield. 相似文献
994.
Xu Liu Xiao-Jing Pang Yuan Liu Wen-Bo Liu Yin-Ru Li Guang-Xi Yu Yan-Bing Zhang Jian Song Sai-Yang Zhang 《Molecules (Basel, Switzerland)》2021,26(13)
Tubulin has been regarded as an attractive and successful molecular target in cancer therapy and drug discovery. Vicinal diaryl is a simple scaffold found in many colchicine site tubulin inhibitors, which is also an important pharmacophoric point of tubulin binding and anti-cancer activity. As the continuation of our research work on colchicine binding site tubulin inhibitors, we designed and synthesized a series of diarylamide N-containing heterocyclic derivatives by the combination of vicinal diaryl core and N-containing heterocyclic skeletons into one hybrid though proper linkers. Among of these compounds, compound 15b containing a 5-methoxyindole group exhibited the most potent inhibitory activity against the tested three human cancer cell lines (MGC-803, PC-3 and EC-109) with IC50 values of 1.56 μM, 3.56 μM and 14.5 μM, respectively. Besides, the SARs of these compounds were preliminarily studied and summarized. The most active compound 15b produced the inhibition of tubulin polymerization in a dose-dependent manner and caused microtubule network disruption in MGC-803 cells. Therefore, compound 15b was identified as a novel tubulin polymerization inhibitor targeting the colchicine binding site. In addition, the results of molecular docking also suggested compound 15b could tightly bind into the colchicine binding site of β-tubulin. 相似文献
995.
Continuous output from a Nd:YVO? crystal around 1073 nm was studied. The output of 1064 nm was suppressed with a Type I phase-matching LiB?O? (LBO) crystal rotated by 45°. With a pump power of 4.5 W, a 300 mW continuous output at 1073 nm was achieved for what we believe is the first time, and the optical-to-optical efficiency was 7%. With an adjustable LBO crystal, the wavelength is tunable from 1073.2 to 1073.5 nm. Even simultaneous output of 1066 and 1073 nm was realized by adjusting the LBO crystal. The experiments proved related theoretical analysis. 相似文献
996.
The phase behavior of Airy beams is studied, and their Gouy phase is defined. Analytic expressions for the idealized, infinite-energy type beam are derived. They are shown to be excellent approximations for finite-energy beams generated under typical experimental conditions. 相似文献
997.
Layer-by-layer assembly and UV photoreduction of graphene-polyoxometalate composite films for electronics 总被引:1,自引:0,他引:1
Li H Pang S Wu S Feng X Müllen K Bubeck C 《Journal of the American Chemical Society》2011,133(24):9423-9429
Graphene oxide (GO) nanosheets and polyoxometalate clusters, H(3)PW(12)O(40) (PW), were co-assembled into multilayer films via electrostatic layer-by-layer assembly. Under UV irradiation, a photoreduction reaction took place in the films which converted GO to reduced GO (rGO) due to the photocatalytic activity of PW clusters. By this means, uniform and large-area composite films based on rGO were fabricated with precisely controlled thickness on various substrates such as quartz, silicon, and plastic supports. We further fabricated field effect transistors based on the composite films, which exhibited typical ambipolar features and good transport properties for both holes and electrons. The on/off ratios and the charge carrier mobilities of the transistors depend on the number of deposited layers and can be controlled easily. Furthermore, we used photomasks to produce conductive patterns of rGO domains on the films, which served as efficient microelectrodes for photodetector devices. 相似文献
998.
999.
Chao-Fan Lu Sheng-Hui Wang Xiao-Jing Pang Ting Zhu Hong-Li Li Qing-Rong Li Qian-Yu Li Yu-Fan Gu Zhao-Yang Mu Min-Jie Jin Yin-Ru Li Yang-Yang Hu Yan-Bing Zhang Jian Song Sai-Yang Zhang 《Molecules (Basel, Switzerland)》2020,25(23)
Chalcone is a common scaffold found in many biologically active compounds. The chalcone scaffold was also frequently utilized to design novel anticancer agents with potent biological efficacy. Aiming to continue the research of effective chalcone derivatives to treat cancers with potent anticancer activity, fourteen amino chalcone derivatives were designed and synthesized. The antiproliferative activity of amino chalcone derivatives was studied in vitro and 5-Fu as a control group. Some of the compounds showed moderate to good activity against three human cancer cells (MGC-803, HCT-116 and MCF-7 cells) and compound 13e displayed the best antiproliferative activity against MGC-803 cells, HCT-116 cells and MCF-7 cells with IC50 values of 1.52 μM (MGC-803), 1.83 μM (HCT-116) and 2.54 μM (MCF-7), respectively which was more potent than the positive control (5-Fu). Further mechanism studies were explored. The results of cell colony formatting assay suggested compound 10e inhibited the colony formation of MGC-803 cells. DAPI fluorescent staining and flow cytometry assay showed compound 13e induced MGC-803 cells apoptosis. Western blotting experiment indicated compound 13e induced cell apoptosis via the extrinsic/intrinsic apoptosis pathway in MGC-803 cells. Therefore, compound 13e might be a valuable lead compound as antiproliferative agents and amino chalcone derivatives worth further effort to improve amino chalcone derivatives’ potency. 相似文献
1000.
Wang Zheng Chen Jiaxin Ye Bingyu Pang Peipei Ma Zhen Chen Hongyu Nan Junmin 《Journal of Solid State Electrochemistry》2020,24(4):843-853
Journal of Solid State Electrochemistry - A series of pore-controllable polyamine (PAI) layer-coated polyolefin (PE) separators (PAI-PE-1, PAI-PE-2, and PAI-PE-3) are prepared by using a... 相似文献