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《中国化学快报》2019,30(11):1951-1954
Utilization of intermolecular Friedel-Crafts and intramolecular condensation reaction,novel 1,3-di-(pyridine-2-yl)benzene(N,C,N terdentate) skeleton with electro-withdrawing group in 6' position of pyridyl and a cyclization between 6' position of pyridyl and 6 position of benzyl ring were firstly designed and synthesized.The structures of these novel N,C,N terdentate were confirmed by NMR,MS and X-ray single crystalanalyses.The photophysical properties of these compounds were briefly explored. 相似文献
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Fricke Christian Harms Hauke Maskow Thomas 《Journal of Thermal Analysis and Calorimetry》2020,141(5):1933-1942
Journal of Thermal Analysis and Calorimetry - A sudden expansion is a classical problem which is happened in different industries such as energy conversion, environmental control, and chemical... 相似文献
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基于Hilbert空间标架理论,借助算子工具,用己有连续广义标架构造了新连续广义标架,并给出了有限个连续广义标架和构成新连续广义标架的充要条件,为构造连续广义标架提供了新方法。 相似文献
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首先证明了M-矩阵的H-相容分裂都是正则分裂,反之不成立.这表明对于M-矩阵而言,其正则分裂包含H-相容分裂.然后针对系数矩阵为M-矩阵的线性互补问题,建立了两个收敛定理:一是模系多分裂迭代方法关于正则分裂的收敛定理;二是模系二级多分裂迭代方法关于外迭代为正则分裂和内迭代为弱正则分裂的收敛定理. 相似文献
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Let f(z) be a meromorphic function in the complex plane, whose zeros have multiplicity at least k + 1(k ≥ 2). If sin z is a small function with respect to f(z), then f~(k)(z)-P(z) sin z has infinitely many zeros in the complex plane, where P(z) is a nonzero polynomial of deg(P(z)) ≠ 1. 相似文献
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In this study, tetracarboxylic manganese phthalocyanine coated nano-zinc oxide (MnC4Pc-ZnO) composite material was prepared by in-situ growth method and modified with indium tin oxide (ITO) glass electrode to construct a photoelectrochemical (PEC) sensor. A PEC sensor for the determination of amlodipine besylate (AB) was developed for the first time based on the principle of precipitation reaction between heavy metal ions and dihydropyridine and the recombination suppression effect of the material. The morphology and optical properties of the MnC4Pc-ZnO composites were characterized by scanning electron microscopy (SEM) and ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS). Chronoamperometry (i-t) and electrochemical impedance spectroscopy (EIS) were used to study the PEC behavior of ITO electrodes modified by MnC4Pc-ZnO composite material. The study found that the MnC4Pc-ZnO composite material has a good photocurrent response to AB, and there was a good linear relationship between the concentration range of 75 nM-250 μM, the linear equation was I(μA)=−5.2×10−8×lgC+3.2×10−8 (r=0.9947), a limit of detection (LOD) of 20 nM. In addition, MnC4Pc-ZnO/ITO also has good selectivity and stability. The PEC sensor detects amlodipine besylate tablets, amlodipine besylate dispersible tablets, and biological samples, with standard addition recovery rates of 96.11 % and 103.96 %, respectively. The determination result has good accuracy, and the PEC sensor provides a new method for detecting AB. 相似文献
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《中国化学快报》2021,32(9):2877-2881
Tumor drug resistance and systemic side effects of chemotherapeutic drugs are the main reasons for the failure of cancer treatment. In recent years, it was found that some natural active ingredients can reverse MDR and regulate body immunity to enhance the efficacy and reduce toxicity of chemotherapeutic drugs. In this paper, a new nanosuspensions, HCPT and QUR hybrid nanosuspensions (HQ-NPs), was prepared by the microprecipitation-high pressure homogenization method to reverse tumor drug resistance, reduce toxicity, and increase therapeutic efficacy. The in vitro investigation results showed that HQ-NPs had a unique shape (particle size was about 216.3 ± 5.9 nm), changed crystalline, and different dissolution rates compared with HCPT-NPs and QUR-NPs, which is attributed to the strong intermolecular forces between HCPT and QUR as indicated by the results of the molecule dock. It was verified that the HQ-NPs could double the retention of HCPT in cells and enhance the cytotoxicity to A549/PTX cells in vitro tests compared with HCPT-NPs. We also found that HQ-NPs can significantly enhance the accumulation of HCPT in tumor sites, improve the antitumor activity of HCPT, and protect the immune organs and other normal tissues (P < 0.01), compared with HCPT-NPs. Therefore, hybrid nanosuspensions can offer promising potential as the drug delivery system for HCPT and QUR to increase the therapeutic efficacy and reduce the toxicity of HCPT. 相似文献
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Journal of Cluster Science - In this paper, a series of light-emitting copper(I) iodide inorganic–organic hybrid clusters has been synthesized, and they are 0D-Cu2I2(fmp)4 (1,... 相似文献