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51.
再论Pedoe不等式的高维推广及应用 总被引:31,自引:0,他引:31
本文对欧氏空间E~n中的两个n维单形,给出了著名的Pedoe不等式的一个实质性推广,并讨论了它的应用. 相似文献
52.
Applicability of the angular properties of scatter elements as a tool to achieve improved slow light performance with small group velocity dispersion and large bandwidth in photonic crystal waveguides is investigated. A polyatomic photonic crystal waveguide, including two scatter elements with different geometrical shapes in each primitive cell, is proposed to investigate the feasibility of our method. Numerical results show that a versatile control of the dispersion relation of slow light modes, with large normalized delay-bandwidth products ranging from 0.2085 to 0.3394, can be obtained using a unique geometrical parameter. 相似文献
53.
Hua Li Lihua Li Xiaoshuang Chen 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(11):1935-1937
Based on the viscosities of HEP (11α-Hydroxy-16α, 17α-epoxyprogesterone) in chloroform from 287.65 to 321.15 K, the data of viscosities were correlated using the polynomial equation. The results showed that the model agreed very well with the experimental data. 相似文献
54.
Sangni Jiang Wenliang Wang Lihua Dong Xinxin Yan Shengran Li Weikang Mei Xintao Xie Yuanhua Zhang Sanrong Liu Prof. Xifei Yu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(49):12589-12598
Choline phosphate lipids have been designed and developed as new-generation zwitterionic nanocarriers with excellent biocompatibility and bioorthogonality to provide a more programmable performance for cancer therapy. However, there is a lack of spatiotemporal and reversible control for drug release at target tumor cells, which can lead to severe adverse effects to normal tissue and discounted treatment outcome. Here, light-inducible Lip-cRGDfk/ICG/Dox liposomes were developed for synergistic cancer therapy. ICG can effectively convert light energy into selective heating in a local environment upon laser irradiation, thus inducing thermal ablation of tumor cells, and further reversibly trigger the spatiotemporal release of anticancer drugs (Dox) at tumor cells due to the conformation transformation of CP lipids to synergistically kill tumor cells. That Lip-cRGDfk/ICG/Dox exhibited a significant improvement for breast cancer therapy in vitro and in vivo is also demonstrated, thus it can serve as an efficient platform to noninvasively and spatiotemporally control the activation of cytotoxicity at tumor cells for precision cancer therapy. 相似文献
55.
Lihua Zuo Heng Meng Jingjing Wu Zhen Jiang Shuying Xu Xingjie Guo 《Journal of separation science》2013,36(3):517-523
In this study, the enantioseparation of zopiclone, repaglinide, chlorphenamine maleate, brompheniramine maleate, dioxopromethazine hydrochloride, promethazine hydrochloride, liarozole, carvedilol, homatropine hydrobromide, homatropine methylbromide, venlafaxine, and sibutramine hydrochloride has been investigated using β‐CD in combination with a chiral ionic liquid (IL), 1‐ethyl‐3‐methylimidazolium‐L‐lactate. The influence of the type of IL and its concentration, BGE pH, and chain length of the IL cations on the resolution are discussed. Finally, the proposed method was successfully applied for the chiral impurity determination of eszopiclone in pharmaceutical tablets after validation with respect to accuracy and precision, linearity range, selectivity, repeatability, LOD and LOQ. It is assessed that the chiral impurity determination in the commercial tables is fewer than 0.1%. 相似文献
56.
Yongtao Bai Lihua Song Yongheng Zhang Guoliang Dai Weidong Zhang Shanshan Song Hong Sun Wen Jing Meijuan Xu Wenzheng Ju 《Biomedical chromatography : BMC》2019,33(9)
A highly selective and efficient LC–MS/MS method was developed to determine the plasma concentration of magnolol, hesperidin, neohesperidin and geniposide following oral administration of Zhi‐Zi‐Hou‐Po decoction in normal and depressed rats. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an XTerra® MS C18 column using a gradient elution with a mobile phase composed of acetonitrile–0.1% aqueous formic acid. The proposed method was validated to be specific, accurate and precise for the analytes determination in plasma samples. The calibration curves displayed good linearity over definite concentration ranges for the analytes. The intra‐ and inter‐day precision of the proposed method at three different levels were all within <11.13% and the relative errors ranged from ?8.46 to 8.93%. The recovery of the four compounds ranged from 82.72 to 89.08% and no apparent matrix effect was observed during sample analysis. After full validation, the established method was successfully applied for comparing the pharmacokinetics of four components between normal and depressed rats. The results showed that the AUC and Cmax of four analytes in depressed rats were significantly different from those in normal rats and might provide helpful information to guide the clinical use of Zhi‐Zi‐Hou‐Po to treat depression. 相似文献
57.
Guifang Ju Yihua Hu Li Chen Xiaojuan Wang Lihua Hung 《Applied Physics A: Materials Science & Processing》2014,114(3):867-874
We investigate the persistent luminescence in europium-doped SrMg2(PO4)2 upon codoping with auxiliary terbium. Luminescence properties of the phosphors, including photoluminescence, luminescence decay and thermoluminescence, are systematically studied. SrMg2(PO4)2:Eu2+ shows only a weak persistent luminescence, and codoping with Tb3+ is necessary to obtain considerable persistent luminescence. An energy level scheme is constructed to convey reasonable trapping and detrapping processes in the material. 相似文献
58.
Deliang Kong Lihua Guo Meng Tian Shumiao Zhang Zhenzhen Tian Huayun Yang Ye Tian Zhe Liu 《应用有机金属化学》2019,33(1)
Fifteen organometallic Ir(III) half‐sandwich complexes ( 1A – 5C ) having the general formula [(η5‐Cpx)Ir(N^N)Cl]PF6 (Cpx = Cp*, tetramethyl(phenyl)cyclopentadienyl (Cpxph) or tetramethyl(biphenyl)cyclopentadienyl (Cpxbiph); N^N = diamine) have been synthesized and characterized. The molecular structure of 1A was determined using single‐crystal X‐ray diffraction analysis. The hydrolysis of 1A – 5C was monitored using UV–visible spectra. Complexes 3A – 3C showed catalytic activity for the oxidation of NADH to NAD+, where 3C showed the highest turnover number of 29.9 within 450 min. Cytotoxicity examination by MTT assay was carried out against two human cancer cell lines (HeLa and A549) after 24 or 48 h drug treatment. The complexes showed high potency, where the most potent complex ( 3C ; IC50 = 3.4 μM) was six times more active than cisplatin against A549 cells after 24 h drug exposure. Cytotoxic potency towards A549 cells increased with phenyl substitution on Cp ring: Cpxbiph > Cpxph > Cp*. In addition, the biological studies showed that 3C caused cell apoptosis and cell cycle arrest at G1 phase in A549 cancer cells. Moreover, 3C increased the level of reactive oxygen species markedly after 24 h, which may provide an important basis for killing cancer cells. Confocal laser scanning microscopy was used to track 3C in A549 cells. The cellular localization experiment showed that 3C targeted lysosomes and caused lysosomal damage. 相似文献
59.
Xingxing Ge Xicheng Liu Zhenzhen Tian Shujiao Chen Xinyu Liu Lihua Guo Peiwei Gong Baoping Ling Xiang‐Ai Yuan Zhe Liu 《应用有机金属化学》2019,33(11)
Four half‐sandwich rutheniumII (RuII) complexes with triphenylamine‐modifed dipyridine frameworks were synthesized and characterized. The cytotoxicity of target complexes toward A549 (lung cancer cells), HeLa (cervical cancer cells) and HepG2 (hepatoma cells) were obtained by the MTT assay, which were superior to cisplatin with the IC50 values changed from 2.4 ± 0.1 μM to 9.2 ± 2.7 μM. Meanwhile, complexes possess the ability of antimetastasis to cancer cells. RuII complexes could be transported by serum albumin, catalyze the conversion of NADH (the reduced state of nicotinamide‐adenine dinucleotide) to NAD+ and induce the accumulation of reactive oxygen species, which confirmed the antineoplastic mechanism of oxidation. RuII complexes could enter A549 cells followed by a non‐energy dependent cellular uptake mechanism, target lysosomes with the Pearson's colocalization coefficient of 0.75, lead to lysosomal damage, disturb the cell cycle (S phase), and eventually induce apoptosis. The results demonstrate that these RuII complexes are potential anticancer agents with dual functions, including metastasis inhibition and lysosomal damage. 相似文献
60.
Zhimei Wei Quanchao Zhang Lihua Wang Minle Peng Xiaojun Wang Shengru long Jie Yang 《Journal of Polymer Science.Polymer Physics》2012,50(20):1414-1420
The focus of this work is the preparation of aramid nanofibers via electrospinning technology and the study of their adsorption properties. In this article, aramid nanofibers were prepared by electrospinning aramid fibers solution with the addition of lithium chloride (LiCl). It showed a good adsorption capacity when methylene blue (MB) was used as the model target. There were much larger adsorption amounts and faster kinetics of uptaking target species of electrospun aramid nanofibers to MB than that of electrospun polyethersulfone (PES) nanofibers. Compared with activated carbon, aramid nanofibers also have a much faster adsorption rate to MB. Aramid nanofibers were subsequently used to effectively remove endocrine disruptors such as bisphenol A (BPA), phenol (Phe), and p‐hydroquinone (BPhe) from their aqueous solutions. Additionally, molecule imprinted technology enhances aramid nanofibers with much higher adsorption amounts and special adsorption property for endocrine disruptors. These results showed that aramid nanofibers have the potential to be used in environmental applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献