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991.
L. N. Yin Y. Li J. Wang Y. M. Kong Y. Zhai B. X. Wang K. Li X. D. Zhang 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(13):2049-2056
The Er3+:Y3Al5O12, an upconversion luminescence agent, which is able to transform the visible light to ultraviolet light, was synthesized by nitrate-citric acid method. And then, a novel photocatalyst, Er3+:Y3Al5O12/ZnO composites, was prepared by ultrasonic dispersing and liquid boil method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the structural morphology and surface properties of the Er3+:Y3Al5O12/ZnO. Azo Fuchsine dye was selected as target organic pollutant to inspect the photocatalytic activity of Er3+:Y3Al5O12/ZnO. The key parameters affecting the photocatalytic activity of Er3+:Y3Al5O12/ZnO, such as Er3+:Y3Al5O12 content, heat-treatment temperature and heat-treatment time, were studied. In addition, the effects of dye initial concentration, Er3+:Y3Al5O12/ZnO amount and solar light irradiation time were also reviewed, as well as the photocatalytic activity in degradation of other organic dyes were compared. It was found that the photocatalytic activity of Er3+:Y3Al5O12/ZnO was much superior to pure ZnO under the same conditions. Thus, the Er3+:Y3Al5O12/ZnO is a useful photocatalyst for the wastewater treatment because it can efficiently utilize solar light by converting visible light into ultraviolet light. 相似文献
992.
Ji Wang Wen-Zhu Zhai Yike Zou Jing-Jing Zhu Juan Xiong Yun Zhao Guo-Xun Yang Hui Fan Mark T. Hamann Gang Xia Jin-Feng Hu 《Tetrahedron letters》2012,53(21):2654-2658
Two new phloroglucinols, named eucalyptals D (1) and E (2), along with a related known compound (euglobal-In-3, 3) were isolated from the fruits of Eucalyptus globulus. Their structures were established on the basis of extensive spectroscopic studies, revealing that they share a common 3,5-diformyl-isopentyl phloroglucinol unit, but each is instead coupled to a different sesquiterpenoid skeleton (aromadendrene in 1, cadinene in 2, and a spirosesquiterpene in 3). Compound 1 possessed an unusual seven-membered D ring with an ether bridge between C-2 of the aromadendrene moiety and C-2′ of the aromatic unit. The absolute configuration of the isolates was defined by the comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Compounds 1–3 exhibited significant in vitro cytotoxicities against a few human cancer cell lines (Huh-7, Jurkat, BGC-823, and KE-97) using the CellTiter-GloTM luminescent cell viability assay method. 相似文献
993.
液相色谱-串联质谱法同时测定贝类中大田软海绵酸、鳍藻毒素、蛤毒素和虾夷扇贝毒素 总被引:3,自引:0,他引:3
建立了同时测定贝类中大田软海绵酸(okadaic acid, OA)及其衍生物鳍藻毒素(dinophysistoxin-1, DTX-1)、蛤毒素(pectenotoxin-2, PTX-2)和虾夷扇贝毒素(yessotoxin, YTX)的液相色谱-串联质谱分析方法。样品经甲醇提取,固相萃取柱净化,C18色谱柱分离,经含甲酸和甲酸铵的乙腈-水溶液为流动相梯度洗脱,选择反应监测(SRM)模式检测,正、负离子切换扫描,基质标准校正,外标法定量。结果表明,OA、DTX-1和YTX的线性范围为2.0~200.0 μg/L,定量限(以信噪比(S/N)≥10计)为1.0 μg/kg; PTX-2的线性范围为1.0~100.0 μg/L,定量限为0.5 μg/kg;几种化合物的添加平均回收率为83.1%~105.7%,相对标准偏差(RSD)为3.16%~9.29%。成功应用本法对黄海灵山湾海域采集的贝类样品进行了分析,发现部分样品中含有大田软海绵酸、鳍藻毒素、蛤毒素和虾夷扇贝毒素。 相似文献
994.
正A series of 2,6-disubstituted-4-morpholinothieno[3,2-d]pyrimidine derivatives were synthesized and their cytotoxic activity against H460,HT-29,MDA-MB-231,U87MG and H1975 cancer cell lines were evaluated in vitro.Most of the target compounds exhibited moderate to excellent activity to the tested cell lines.The most promising compound 23(0.84μmol/L,0.23μmol/L, 2.52μmol/L,1.80μmol/L) was 1.0,2.9,29.3 and 4.3 times more active than GDC-0941(0.87μmol/L,0.66μmol/L,73.8μmol/L, 7.77μmol/L) against H460,HT-29,MDA-MB-231 and U87MG cell lines,respectively. 相似文献
995.
996.
997.
Based on the stationary zero-curvature equation and the Lenard recursion equations, we derive the coupled modified Korteweg–de Vries (cmKdV) hierarchy associated with a 3×3 matrix spectral problem. Resorting to the Baker–Akhiezer function and the characteristic polynomial of Lax matrix for the cmKdV hierarchy, we introduce a trigonal curve with three infinite points and two algebraic functions carrying the data of the divisor. The asymptotic properties of the Baker–Akhiezer function and the two algebraic functions are studied near three infinite points on the trigonal curve. Algebro-geometric solutions of the cmKdV hierarchy are obtained in terms of the Riemann theta function. 相似文献
998.
Weidong Chen Pengfei Zhai Heng Zhu Yongbo Zhang 《The Journal of the Operational Research Society》2014,65(7):1068-1077
In this paper, a rectangular layer-packing algorithm (RLPA) combined with modified genetic algorithm (GA) or particle swarm optimization (PSO) algorithm is developed to solve the problem with emerging restraints, which is raised from the two-dimensional rectangular packing problem with some small rectangles that need to be packed into a fixed rectangular object. RLPA is designed from the BL algorithm and lowest horizontal line algorithm. GA and PSO are also modified to satisfy the constraint conditions. Best GA or PSO parameters are obtained by conducting experiments on some typical instances. The results are also compared, which validate the quality of the solutions and show the effectiveness of the modified algorithm. 相似文献
999.
1000.
Yan-Hong Zhou Shu-Ni Li Quan-Guo Zhai Yu-Cheng Jiang Man-Cheng Hu 《The Journal of chemical thermodynamics》2010,42(6):764-772
The solubilities, densities and refractive indices data for the four ternary systems ethylene glycol + MCl + H2O (M = Na, K, Rb, Cs) at different temperatures were measured, with mass fractions of ethylene glycol in the range of 0 to 1.0. In all cases, the presence of ethylene glycol significantly reduces the solubility of the salts in aqueous solution. The experimental data of density, refractive index and solubility of saturated solutions for these systems were correlated using polynomial equations as a function of the mass fraction of ethylene glycol. On the other hand, the refractive index and density of unsaturated solutions was also determined for the four ternary systems with varied unsaturated salt concentrations. Values for both the properties were correlated with the salt concentrations and proportions of ethylene glycol in the solutions. 相似文献