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101.
102.
Effect of Aspect Ratio Distribution on Localized Surface Plasmon Resonance Extinction Spectrum of Gold Nanorods 下载免费PDF全文
TAO Jun LU Yong-Hua ZHENG Rong-Sheng LIN Kai-Qun XIE Zhi-Guo LUO Zhao-Feng LI Sheng-Li WANG Pei MING Hai 《中国物理快报》2008,25(12):4459-4462
Gold nanorods with different aspect ratios are prepared in micells using a seeded growth method. Their extinction spectra are observed with an UV-visible spectrophotometer and analysed theoretically. It is known that there are two plasmon resonance peaks for gold nanorod corresponding to transverse and longitudinal plasmon resonance respectively. Moreover, the longitudinal plasmon resonance peak shifts to long wavelength when we increase the aspect ratio determined from TEM. Especially, we model the extinction spectrum using Gans' theory and compare it with our experimental result. Considering the aspect radios distribution of gold nanorods, it is found that longitudinal plasmon resonance peak will be wider than the nanorods with single aspect ratio, which is consistent with our experimental result. In addition, the effect of dielectric constant of surrounding medium is considered. 相似文献
103.
The interaction between cucurbit[8]uril(Q[8]) and oroxin B(ORB) was investigated by UV-visible(UV-Vis) spectroscopy, isothermal titration calorimetry(ITC), mass spectrum(MS) and nuclear magnetic resonance(NMR) spectroscopy. The results showed that ORB formed a 2:1 inclusion complex with Q[8] with a binding constant of 8.266×105 L2·mol-2. ORB had good scavenging ability for 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate)(ABTS) free radicals(IC50=5.74 μmol/L) and the addition of Q[8] did not significantly affect the antioxidant activity of ORB(IC50=5.76 μmol/L). A phase solubility experiment revealed a 1.86-fold increase in the solubility of ORB when c(Q[8])=100 μmol/L. In vitro drug release experiments showed that the release rate for ORB@Q[8] complex was lower than that of ORB in artificial intestinal juice, and higher than that of ORB in artificial gastric juice. 相似文献
104.
Determining the catalytically active phase in electrochemical CO2 reduction has been challenging. In their work recently published in Nature Communications on July 8, 2020, Zhang et al. studied the phase transition of a tannin-lead(II) complex in electrochemical CO2 reduction and revealed that the in-situ formed hydrocerussite[Pb3(CO3)2(OH)2] is the stable active phase for formate production. This new finding may help settle the debate on the real active site of Pb-based materials for CO2 electroreduction. 相似文献
105.
Journal of Nonlinear Science - Predator–prey interactions are among the most complicated interactions between biological species, in which there may be both direct effect (through predation)... 相似文献
106.
选择了市场上口碑好、占有率高的3款便携式水质现场应急检测设备,通过准确度、精密度、检测时长及价格等指标,以权重积分法对3款仪器进行了比选,结果表明德国MN公司的PF-12型便携式多参数分光光度计的综合性能最优. 相似文献
107.
LB薄膜中四新戊氧基酞菁锌和四壬基酞菁铜分子聚集体的吸收光谱的温度特性 总被引:1,自引:2,他引:1
本文制备了四新戊氧基酞菁锌(Tetra-neopentoxy phthalocyanine zine)(TNPPeZn)和四壬基酞菁铜(Tetra-nonyl phthalocyanine copper)(TNPeCu)两种酞菁衍生物的Langmuir-Blodgett(LB)薄膜.通过测量10~473K温度下的吸收光谱,研究了两种薄膜的分子聚集状态.TNPPeZn的LB薄膜中,存在着分子单体和分子二聚体,在吸收光谱中分别表现为680nm和620nm的吸收峰.随着温度的升高,分子单体逐渐转变为分子二聚体,这个过程是不可逆的.TNPeCu的LB薄膜中,除了分子单体和分子二聚体以外,还有吸收为740nm的分子J聚集体存在.随着温度的变化,J聚集体发生可逆变化. 相似文献
108.
109.
The effective light-cone Harniltonian is extended to include the SU(3) flavor mixing interaction besides the confining potential. Solving the coupled J = 0 mass eigen equations for the up, down, and strange quark components numerically, the masses of π^0 and η, their radial wave functions, and rms radii are obtained in agreement with the experimental data. 相似文献
110.
辐照诱导的人正常肝细胞系HL-7702细胞延迟效应 总被引:1,自引:0,他引:1
利用X射线辐照人正常肝细胞系HL-7702细胞, 运用胞质分离阻滞微核法实验检测细胞微核率,AnnexinV FITC细胞凋亡检测试剂盒检测细胞凋亡率, 细胞微核率和凋亡率随着辐照剂量的增加而显著增加。X射线照射后细胞传代培养, 第7代时不同剂量辐照后子代细胞微核率和凋亡率同未辐照细胞相比已无明显区别。 对不同剂量辐照后传代7代的细胞再次照射2.5 Gy的相同剂量,发现它们细胞微核率和凋亡率存在明显差异,即初次受辐照剂量高的细胞, 再次以相同剂量辐照后的微核率和凋亡率也高. 这些结果表明,X射线辐照导致了HL-7702细胞基因组不稳定性这一辐射延迟效应,再次辐照使得辐射的延迟效应得以明显的表现。 Human normal liver cell line HL-7702 cells were irradiated with different doses of X rays. Micronucleus and apoptosis rates in the irradiated cells were measured with cytokinesis block micronucleus method and Annexin V FITC apoptosis detection kit, respectively. Experimental data showed that the micronucleus and apoptosis rates increased obviously with increasing irradiation dose. After seven population doublings, the micronucleus and apoptosis rates of the cells surviving exposure to the X rays reduced to the same levels as non irradiated control cells; the progenies of the cells were secondly exposed to X rays at the same dose of 2.5 Gy. We found that the progenies of the cells surviving the first irradiations of the various doses showed markedly differential micronucleus frequencies and apoptotic rates. Although the same dose of 2.5 Gy was applied in the second irradiations, the micronucleus frequencies and apoptotic rates of the progenies of the cells initially exposed at higher doses were significantly higher than the others. These results indicate that X rays lead to genomic instability in HL 7702 cells, which is an important manifestation of radiation induced delayed effect, and a second radiation stimulus makes the delayed effect in the progeny of the previously irradiated cells be expressed obviously. 相似文献