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1.
合成了3种D-氨基葡萄糖席夫碱化合物,研究了它们的表面增强拉曼光谱、傅里叶变换拉曼光谱,探讨了它们在银溶胶上的吸附状态和表面增强机理,发现这类化合物以化学吸附模式为主,结构相似的化合物在银溶胶上的吸附状态不一定完全相同。  相似文献   

2.
本文利用表面增强拉曼光谱研究了增感染料1556、798在银电极上的吸附,通过比较染料的固体拉曼光谱和染料的表面增强光谱,我们发现两种染料在银电极表面的吸附行为不完全相同,吸附时染料分子的平面基本上与电极表面相垂直。  相似文献   

3.
赵冰  尾崎幸样 《电化学》2001,7(2):185-188
由水杨醛衍生得到的Schiff碱由于其具有起因于受激分子内质子转移的光致 (热致 )变色性质而受到了人们的重视 .本文利用表面增强拉曼光谱研究了该类化合物在金、银基底及银溶胶表面上的拉曼光谱 ,比较了不同基底对吸附分子结构的影响  相似文献   

4.
报道了C70分子吸附于铜表面的增强拉曼光谱.通过与正常拉曼光谱以及银表面SERS谱的比较发现,C70分子与铜表面之间的吸附属于物理吸附,增强机制主要是电磁增强.C70分子在银表面上的吸附状态与铜表面上的不同,这导致了两者特征峰谱线强度分布存在差异.以C60的振动模式为参考,推断出C70分子在2种金属表面上的吸附状态可能分别处于使碳笼的挤压振动模接近于“平躺”和“竖直”的2种状态.  相似文献   

5.
合成了三种含氨基酸席夫碱的5-氟尿嘧啶类衍生物,用元素分析和1H NMR表征了它们的结构;用拉曼光谱(RS)和表面增强拉曼光谱(SERS)研究目标化合物在银溶胶上的吸附状态,推测其SERS增强机理.结果表明:在银溶胶表面上,羧基氧原子与银形成化学建,苯环是稍微倾斜地吸附在银胶面上,其它部分则平躺吸附于银溶胶表面.  相似文献   

6.
用密度泛函理论B3LYP/6-311G++(d, p)方法优化了麻黄碱分子结构,计算了理论拉曼光谱,以此为依据,对麻黄碱的常规拉曼光谱进行了详细的指认,用Gaussview5.0软件对其峰位进行了详细的归属。采用了自组装方法,经氨基化处理后的玻片与银溶胶结合,获得了具有二维结构的纳米银基底,研究了沉积在基底表面麻黄碱的表面增强拉曼光谱,结果表明,实验所得拉曼光谱与理论计算拉曼光谱基本一致,该分子与银纳米表面化学吸附,苯环与银基底垂直。该研究为麻黄碱的快速、痕量检测提供了理论依据,也为冰毒类毒品拉曼光谱分析提供了重要参考。  相似文献   

7.
用一种简单的化学还原方法制备了银纳米粒子包覆的氧化亚铜(Cu2O)纳米复合物。扫描电子显微镜显示Cu2O 为八面体型的纳米粒子,表面光滑,结构对称。包覆的Ag部分占据Cu2O粒子表面。通过比较Ag/Cu2O纳米复合物、Ag溶胶及Cu纳米粒子表面吸附的4-巯基吡啶(4-Mpy)分子表面增强拉曼光谱(SERS)发现,利用此方法得到了Cu2O粒子表面吸附分子的拉曼光谱。银纳米粒子所产生的电磁场增强又增强了吸附在Cu2O上的4-Mpy拉曼信号。这种方法为初步研究Cu2O表面吸附分子性质提供了依据,扩宽了SERS的使用范围,使SERS应用在纳米半导体材料上成为可能。  相似文献   

8.
周光明  盛蓉生 《分析化学》1997,25(4):391-395
研究了在不同耐尔蓝A浓度,银溶胶,激发波长和pH值以及碘离子存在下,耐尔蓝A在银溶胶上的表面增强拉曼光谱特征。  相似文献   

9.
采用化学沉积法制备了表面增强拉曼散射光谱(SERS)银镜基底,用NaCl溶液与HCl溶液除去银镜表面杂质后,通过扫描电子显微镜对基底进行了表征,表明该基底表面的银纳米粒子平均粒径约为200 nm,以对巯基苯胺为探针分子测得其增强因子为4.6×105.利用表面增强拉曼光谱及表面吸附选择定律研究了广谱抗菌药呋喃唑酮在该基底表面的吸附状态,证明呋喃唑酮分子主要是通过CN吸附于银纳米粒子表面的.  相似文献   

10.
报道了维生素PP分子的常规拉曼光谱(NRS)及该分子在活性衬底银胶上的表面增强拉曼散射(SERS),并对它的拉曼特征峰进行了初步的指认和归属.维生素PP的常规拉曼光谱和SERS谱的对比表明,该分子吸附在银表面时,它的C‖O键与银粒子发生电荷转移,碳氧双键打开形成C-O 单键.通过分析可以推断维生素PP通过羰基和氨基垂直或斜立吸附在银表面上.  相似文献   

11.
研究了在阳离子表面活性剂溴化十六烷基三甲铵(CTMAB)存在下, 阴离子染料固红VR盐(FVR)和鱼精脱氧核糖核酸(fsDNA)作用的共振光散射(RLS)光谱特性、影响因素和最佳反应条件. 在pH 5.72和离子强度低于0.01 mol/L的条件下, fsDNA和CTMAB对FVR的共振光散射光谱有协同增强作用, 产生最大散射波长为361 nm的共振光散射增强(RLSE)信号. 在优化实验条件下, 测定fsDNA的线性范围为0.01~2.0 mg/L, 检出限可达2.5 μg/L. 方法能用于合成样中DNA的测定.  相似文献   

12.
共振光散射探针法测定壁画胶结材料中蛋白质含量   总被引:2,自引:2,他引:0  
用酸性铬蓝K(ACBK)为共振光散射探针,对壁画含不同颜料的胶结材料中的蛋白质含量进行了定量测定在pit3.96乙酸-乙酸钠缓冲溶液条件下,在λ=345nm处,以生血清白蛋白(BSA)为标准样品绘制工作曲线测定敦煌壁画中含不同颜料的胶结材料中蛋白质结果分别为:白色颜料1.5361μg/mg;绿色颜料1.5714μg/mg:蓝色颜料1.6801μg/mg;棕色颜料1.8756μg/mg和红色颜料3.2673μg/mg.对BSA测定的线性范围为0.13~10.88μg/L。该方法简单、快速、灵敏度高,平行测定的相对标准偏差(RSD)为3.8%,蛋白质的加标回收率为95%~107%。  相似文献   

13.
A new method of producing tungstic acid with a yield over 98% at room temperature and low acidity is advanced and referred to as Complcx -Homogeneous Precipitation Method. If combined with the treatment of activated charcoal in recovering the remnant tungsten left in the filter liquor, a perfect closed technological process can be obtained. The key to this method is to prevent the formation of pseudo-metatungstatc during scdium rungstate being acidified directly with the aid of the complexing-protecting agent H2O2, The perexo-mtermediate, which was prepated and identified as dipcroxytetratnngstate by IR and Raman analysis by comparison with diperorytetramolybdate, can be decomposed by SO2 tapidly and quantitatively. The tungstic acid precipitate can be filtered and washed easily. The related mechanisin is studied.  相似文献   

14.
The microemulsions formed in the 4-component system water-potassium oleate-hexanol-dodecane have been investigated by time-average light scattering and small angle neutron scattering. A constant volume fraction ratio water: potassium oleate of 1.44 was used and at this constant composition, which gave a pseudo 3-component system, a wide region of the microemulsion domain was examined. In order to interpret the scattering data at finite volume fractions of the dispersed phase, water, allowance had to be made for interactions between the water-in-oil microemulsion droplets. This was carried out using a hard sphere model for the interaction. It is shown that using this model self-consistent results are obtained by light scattering and neutron scattering and an estimate can be made of the size of the particles in concentrated colloidal dispersions.  相似文献   

15.
Although the effectiveness of trehalose as cryoprotectant is proved, the underlying mechanisms have been so far unclear and the formulated hypothesis often contrasting. Experimental findings indicate that the bioprotection causes lie on the ‘solvent’, i.e. on the peculiar interaction mechanisms of trehalose with water, independently on the biostructure nature.  相似文献   

16.
The interaction between congo red (CR) and amikacin (AMK) was studied by resonance Rayleigh scattering (RRS), frequency doubling scattering (FDS) and second-order scattering (SOS) combining with absorption spectrum. In a weak acidic medium, CR combined with AMK to form an ion association complex with the composition ratio of 1∶1 by electrostatic interaction, hydrophobicity and charge transferring effect. As a result, the new spectra of RRS, FDS, and SOS appeared and their intensities were enhanced greatly. The maximum wavelengths of RRS, FDS and SOS were located at 563 nm, 475 nm and 940 nm, and the scattering intensities were proportional to the concentration of AMK. These three methods have very high sensitivities, and the detection limits were 4.0 ng·mL?1 for RRS, 3.6 ng·mL?1 for FDS and 1.9 ng·mL?1 for SOS, respectively. At the same time, the methods have better selectivity. A new method for the determination of trace amounts of AMK with congo red by resonance scattering technique has been developed. The recovery for the determination of AMK in blood serum and urine sample was between 95.5% and 105.5%. In this study, the properties, such as enthalpy of formation, charge distribution and mean polarizability, were calculated by AM1 quantum chemistry method. In addition, the reaction mechanism and the reasons for the enhancement of scattering spectra were discussed.  相似文献   

17.
18.
The effect of α-hydroxy group on the phase behavior in a skin lotion model system was studied by determining the phase diagrams for the two systems acetic acid / Laureth 4 / white oil / water and glycolic acid / Laureth 4 / white oil / water using visual observation by optical microscopy. The two acids when combined with surfactant and water gave an isotropic liquid solution, and a lamellar liquid crystal with different amounts of solubilization showing both acids to act as hydrotropes. The result provided essential information about the differences in the phase behavior which can attribute to the presence of a-hydroxy group in the glycolic acid. Small angle x-ray diffraction was used to determine the boundaries of the lamellar liquid crystal phases in the two systems, both acids were found to be located in the water region in the liquid crystal.  相似文献   

19.
选择酸性染料对低质阔叶材单板进行染色研究,发现此类染料对滇杨木,滇桤木,西南桦有较好的易染性,通过试验得到几例常见木材颜色的染料配比,并对染色工艺进行了初步探讨,结果表明温度在70-80℃,pH=4及助染剂量1.5(wt)%时,染色效果最佳。  相似文献   

20.
Although inelastic (Compton) scattering of a photon off a free electron was well understood about 80 years ago, inelastic scattering off bound electrons remains an incompletely understood process. The availability of synchrotron light sources has led a great enhancement in the precision of experimental measurements involving this process. As a result, approximations made in obtaining numerical predictions of physical observables are being reexamined by theorists. In this article, we present a comparison of experimental measurements to theoretical predictions to assess the need for future advances in both experiment and theory.  相似文献   

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