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排序方式: 共有922条查询结果,搜索用时 121 毫秒
1.
SHANG Anqi ZHAO Lele LI Zhenhua CHENG Zhuang JIN Haixu FENG Zijun CHEN Zhijun ZHANG Haiquan LU Ping 《高等学校化学研究》2022,38(6):1461-1466
Near-infrared(NIR) fluorescent materials with high photoluminescent quantum yields(PLQYs) have wide application prospects. Therefore, we design and synthesize a D-A type NIR organic molecule, TPATHCNE, in which triphenylamine and thiophene are utilized as the donors and fumaronitrile is applied as the acceptor. We systematically investigate its molecular structure and photophysical property. TPATHCNE shows high Tgof 110℃ and Td of 385℃ and displays an aggregation-induced emission(AIE) property. A narrow optical bandgap of 1.65 eV is obtained. The non-doped film of TPATHCNE exhibits a high PLQY of 40.3% with an emission peak at 732 nm, which is among the best values of NIR emitters. When TPATHCNE is applied in organic light-emitting diode(OLED), the electroluminescent peak is located at 716 nm with a maximum external quantum efficiency of 0.83%. With the potential in cell imaging, the polystyrene maleic anhydride(PMSA) modified TPATHCNE nanoparticles(NPs) emit strong fluorescence when labeling HeLa cancer cells, suggesting that TPATHCNE can be used as a fluorescent carrier for specific staining or drug delivery for cellular imaging. TPATHCNE NPs fabricated by bovine serum protein(BSA) are cultivated with mononuclear yeast cells, and the intense intracellular red fluorescence indicates that it can be adopted as a specific stain for imaging. 相似文献
2.
Acta Mechanica Sinica - 相似文献
3.
LI Yuan LI Ruizhe LI Zhenhua WEI Weiqin OUYANG Shuxin YUAN Hong ZHANG Tierui 《高等学校化学研究》2020,36(6):1006-1012
Photothermal Fischer-Tropsch synthesis(FTS) has been extensively studied, but few reports were focused on systematically exploring the influence of support on catalytic performance. Herein, a series of Fe5C2-based catalysts with different supports was fabricated via a one-step wet-chemical method for photothermal conversion of syngas to lower olefins. Under light irradiation, the optimized Fe5C2/α-Al2O3 catalyst demonstrated remarkable photothermal FTS activity, delivering selectivity to lower olefins of 50.3% with a CO conversion rate of 52.5%. Characterization studies using X-ray diffraction and Mössbauer spectroscopy analysis revealed that the active catalyst mainly contained Fe5C2 nanoparticles on α-Al2O3 support. It was found that the weak interaction between active phase and α-Al2O3 could promote the formation of Fe5C2, which contributed to the high selectivity to lower olefins. 相似文献
4.
Ziritaxestat is a first-in-class autotoxin inhibitor. The purpose of this study was to develop a liquid chromatography/electrospray ionization tandem mass spectrometric (LC–MS/MS) method for the determination of ziritaxestat in rat plasma. The plasma sample was deproteinated using acetonitrile and then separated on an Acquity BEH C18 column with water containing 0.1% formic acid and acetonitrile as mobile phase, which was delivered at 0.4 ml/min. Ziritaxestat and the internal standard (crizotinib) were quantitatively monitored with precursor-to-product transitions of m/z 589.3 > 262.2 and m/z 450.1 > 260.2, respectively. The total running time was 2.5 min. The method showed excellent linearity over the concentration range 0.5–2000 ng/ml, with correlation coefficient >0.9987. The extraction recovery was >82.09% and the matrix effect was not significant. Inter- and intra-day precisions (RSD) were <11.20% and accuracies were in the range of −8.50–7.45%. Ziritaxestat was demonstrated to be stable in rat plasma under the tested conditions. The validated LC–MS/MS method was successfully applied to study the pharmacokinetic profiles of ziritaxestat in rat plasma after intravenous and oral administration. Pharmacokinetic results demonstrated that ziritaxestat displayed a short half-life (~3 h) and low bioavailability (20.52%). 相似文献
5.
Guanfeng Lin Tiancai Liu Jingyuan Hou Zhiqi Ren Jianwei Zhou Qianni Liang Zhenhua Chen Wenqi Dong Yingsong Wu 《Journal of fluorescence》2015,25(2):361-367
A sensitive, rapid and novel measurement method for cytokeratin 19 fragment (CYFRA 21–1) in human serum by magnetic particle-based time-resolved fluoroimmunoassay (TRFIA) is described. Built on a sandwich-type immunoassay format, analytes in samples were captured by one monoclonal antibody coating onto the surface of magnetic beads and “sandwiched” by another monoclonal antibody labeled with europium chelates. The coefficient variations of the method were lower than 7 %, and the recoveries were in the range of 90–110 % for serum samples. The lower limit of quantitation of the present method for CYFRA 21–1 was 0.78 ng/ml. The correlation coefficient of CYFRA 21–1 values obtained by our novel TRFIA and CLIA was 0.980. The present novel TRFIA demonstrated high sensitivity, wider effective detection range and excellent reproducibility for determination of CYFRA 21–1 can be useful for early screening and prognosis evaluation of patients with non-small cell lung cancer. 相似文献
6.
Jordan operator algebras are norm‐closed spaces of operators on a Hilbert space with for all . In two recent papers by the authors and Neal, a theory for these spaces was developed. It was shown there that much of the theory of associative operator algebras, in particular, surprisingly much of the associative theory from several recent papers of the first author and coauthors, generalizes to Jordan operator algebras. In the present paper we complete this task, giving several results which generalize the associative case in these papers, relating to unitizations, real positivity, hereditary subalgebras, and a couple of other topics. We also solve one of the three open problems stated at the end of our earlier joint paper on Jordan operator algebras. 相似文献
7.
光驱动C1转换到高附加值化学品的研究进展 总被引:1,自引:0,他引:1
阐述了光驱动C1化学的最新研究进展, 分别对光驱动费托合成、 水煤气变换、 二氧化碳加氢、 甲烷重整和甲醇重整制氢的研究进行了综述, 提出了当前研究存在的问题及发展方向. 相似文献
8.
Huanian Zhang Xiaohan Chen Qingpu Wang Xingyu Zhang Jun Chang Liang Gao Hongbin Shen Zhenhua Cong Zhaojun Liu Huaijin Zhang Jing Li Ping Li 《Applied physics. B, Lasers and optics》2014,114(3):313-317
With graphene as saturable absorber, an Nd:KLu(WO4)2 eye-safe laser operating at 1,425 nm is demonstrated. To the best of our knowledge, this is the first demonstration that an Nd:KLu(WO4)2 laser operates at the eye-safe 1.4-μm region. A maximum total average output power of 170 mW is obtained under the pump power of 9.6 W, corresponding to an optical–optical efficiency of 1.77 %. The minimum pulse width and the highest pulse repetition rate are 153 ns and 97 kHz, respectively. Also the characteristics of the graphene used as saturable absorber for a 1.4-μm laser were studied for the first time. 相似文献
9.
建立了火焰原子吸收光谱法(FAAS)测定锡阳极泥中银含量的方法。文章考察了不同的测定介质、酸度对测定结果的影响。实验结果表明在选定条件下,锡阳极泥中的锡、锑、铅等杂质不干扰银的测定。方法加标回收率在99.2%~103%,精密度实验结果表明,相对标准偏差(RSD,n=11)均小于4%。操作过程简单,能满足生产的需要。 相似文献
10.
Dr. Peng Zhang Qian-Cheng Luo Dr. Zhenhua Zhu Wanrong He Nan Song Junting Lv Xuning Wang Prof. Quan-Guo Zhai Prof. Yan-Zhen Zheng Prof. Jinkui Tang 《Angewandte Chemie (International ed. in English)》2023,62(12):e202218540
The syntheses and magnetic properties of organometallic heterometallic compounds [K(THF)6]{CoI[(μ3-HAN)RE2Cp*4]2} ( 1-RE ) and [K(Crypt)]2{CoI[(μ3-HAN)RE2Cp*4]2} ( 2-RE ) containing hexaazatrinaphthylene radicals (HAN⋅3−) and four rare earth (RE) ions are reported. 1-RE shows isolable species with ligand-based mixed valency as revealed by cyclic voltammetry (CV) thus leading to the isolation of 2-RE via one-electron chemical reduction. Strong electronic communication in mixed-valency supports stronger overall ferromagnetic behaviors in 2-RE than 1-RE containing Gd and Dy ions. Ac magnetic susceptibility data reveal 1-Dy and 2-Dy both exhibit slow magnetic relaxation. Importantly, larger coercive field was observed in the hysteresis of 2-Dy at 2.0 K, indicating the enhanced SMM behavior compared with 1-Dy . Ligand-based mixed-valency strategy has been used for the first time to improve the magnetic coupling in lanthanide (Ln) SMMs, thus opening up new ways to construct strongly coupled Ln-SMMs. 相似文献