Determination of Potassium Ferrocyanide in Foods by Resonance Rayleigh Scattering Method with Basic Triaminotriphenylmethane Dyes

In this work, a sensitive, rapid and simple method for the determination of trace amounts of potassium ferrocyanide in salinized foods and table salt using EV as a RRS probe is established. The detection limit （3σ） of the EV system is 7.8 ng/mL. This new method is more suitable for the determination of the trace amounts of potassium ferrocyanide in colour salinized foods and it can not be disturbed by the color of salinized foods.

Resonance Rayleigh Scattering and Resonance Nonlinear Scattering Methods for Determination of Methylene Blue with 12-Tungstophosphoric Acid

In a pH=0.65―1.5 NaAc-HCl medium, methylene blue（MB） reacts with 12-tungstophosphoric acid （TPA） by virtue of electrostatic attraction and hydrophobic force to form a 3：2 ion-association complex. As a result, the intensities of resonance Rayleigh scattering（RRS）, second-order scattering（SOS） and frequency doubling scatte- ring（FDS） are enhanced greatly. The maximum scattering wavelengths of RRS, SOS and FDS are located at 316, 647 and 311 nm. The increments of scattering intensity（△I） are directly proportional to the concentration of MB in a certain range. The methods exhibited high sensitivity, and the detection limits（3s） for MB are 2.3 ng/mL（RRS method）, 5.6 ng/mL（SOS method） and 6.4 ng/mL（FDS method）, respectively. The effects of coexisting substances have been examined, and the results indicate that the methods have good selectivity. Based on the above researches, a new spectral method for the determination of trace amounts of MB has been developed. It can be applied to the determination of MB in human serum, and the recoveries are 97.5%―105.0%. The results are in good agreement with those obtained by the pharmacopoeia method. In this work, the optimum conditions of the reaction and the influencing factors were investigated. In addition, the reaction mechanism and the reasons of the enhancement of resonance light scattering were discussed.

Interaction Between Mitoxantrone Metal Complex and Titan Yellow by Resonance Rayleigh Scattering Spectra and Its Analytical Application

In a pH 2.4 Britton-Robinson buffer medium, the anthracycline antibiotics mitoxantrone（MXT） could react with metal ions such as Pd（Ⅱ）, Co（Ⅱ） and Cu（Ⅱ） to form 1：2（molar ratio） cationic chelates, which further reacted with the anionic dye titan yellow to form 1：2 ternary ion-association complexes by electrostatic interaction. As a result, the intensity of resonance Rayleigh scattering（RRS） was enhanced greatly. These RRS spectral characteristics of various metal ion systems were similar, and the maximum RRS wavelengths were all located at 454 nm. But the increments of RRS intensities were different in the series of Pd（Ⅱ）〉Co（Ⅱ）〉Cu（Ⅱ）. The enhanced RRS intensities were proportional to the concentration of MXT in a range of 0.03-2.4μg/mL and the detection limit（3σ） was 0.009μg/mL for the Pd（Ⅱ） system. In this study, the optimum conditions of the reactions and the effects of foreign substances were investigated, in addition, the composition and reaction mechanism of ion-association complexes were discussed. Thus a highly sensitive, simple and rapid method is proposed for the determination of MXT in urine and serum samples.

Determination of Matrine and Oxymatrine in Radix Sophorae Flavescentis by Resonance Rayleigh Scattering, Second-order Scattering and Frequency Doubling Scattering Technique

In 0.1 mol/L HCl medium, 12-tungstophosphoric（TP） acid reacted with matrine（Mat） and oxymatrine（Oxy） to form an ion-association complex. As a result, the new spectra of resonance Rayleigh scattering（RRS）, second-order scattering（SOS） and frequency doubling scattering（FDS） appeared and their intensities were enhanced greatly. The maximum scattering wavelengths of RRS, SOS and FDS were located at 370, 670 and 390 nm, respectively. The in-crements of scattering intensity were directly proportional to the concentration of Mat and Oxy in a certain range. Based on this, the method for the determination of matrine and oxymatrine has been established. It has been applied to the determination of matrine and oxymatrine in samples of Radix sophorae flavescentis with satisfactory result. The reaction mechanism and reasons of RRS enhancement were discussed.

Study on Resonance Rayleigh Scattering Spectra of Mercaptopurine-Cu(II)-Nucleic Acid System

In pH 4.8 Britton-Robinson (B-R) buffer solution, Mercaptopurine (MP) could react with Cu(II) to form stable chelate compound, a new Resonance Rayleigh scattering (RRS) spectrum generated and enhanced for the binary system which the highest peak located at 453 nm as detection wavelength. But the RRS spectra could be quenched after adding her- ring milt DNA (hsDNA), salmon milt DNA (sDNA) and calf thymus DNA (ctDNA) into the binary system, respect- tively. And the weakened degree of spectra was directly proportional to the concentration of DNA. The reaction product of three nucleic acid system have identical spectral features, their range of linearity for the relation of spectral intensity with concentration respectively are 0.05 - 0.9 μg.mL-1 for hsDNA, 0.1 - 0.9 μg.mL-1 for sDNA and 0.3 - 0.9 μg.mL-1 for ctDNA;their detection limit respectively are 5 ng.mL-1for hsDNA, 6 ng.mL-1for sDNA, 6 ng?mL-1 for ctDNA. So a new method for determination of DNA was developed and successfully applied to determine the content of the DNA in artificial synthetized samples. At the same time the spectral features of absorption spectra and RRS spectra of the three reaction system, and the eligible reaction conditions and influencing factors were investigated in this paper.

A study on resonance Rayleigh scattering spectra of Humic Acid (HA)

This paper deals with the influences of pH, acidity and ionic intensity of the solutions on the resonance Rayleigh scattering spectra and fluorescence spectra of humic acid. When the pH value is low and the acidity and ionic intensity are high, the resonance Rayleigh spectra and fluorescence spectra both show a tendency of increasing, though the former's intensity is much higher. In combination with the transmission electron microscope data, the factors leading to the occurrence and enhancement of the resonance Rayleigh scattering spectra of humic acid were explored. It is considered that particle enlargement caused by aggregation, the increase of heterogeneity, the increase of hydrophobility, the formation of interface, etc., are the factors leading to the occurrence and enhancement of the resonance Rayleigh scattering spectra of humic acid. As the intensity of the resonance Rayleigh scattering spectra of humic acid is much higher, resonance Rayleigh scattering spectroscopy can be used as a newly developed spectrum technology, which is more sensitive and simpler, to study humic acid and its complicated behaviors.

人血清白蛋白共振Rayleigh光散射检测氟离子

通过研究F- 离子对人血清白蛋白(HSA)溶液共振Rayleigh光散射(RLS)的增强效应 ,建立一种基于生物蛋白RLS增强测定环境中氟离子的新型检测方法。实验条件为λex=λem=368nm ,pH=5.80 ,t=32℃。结果表明 ,应用含氟离子溶液与空白溶液在368nm处RLS差值(ΔI) ,标准曲线法测定样品中的氟离子 ,方法线性范围为4.78～16.2μg/mL ,r=0.992 ,检出限为1.43μg/mL。方法精密度(RSD为1.31%～5.72 %)和准确度(回收率R为91 %～109 %)

金纳米微粒与盐酸氯丙嗪相互作用的共振Rayleigh散射光谱研究及其分析应用

在pH1.8～3.3的酸性介质中,金纳米微粒本身有一定的共振瑞利散射（RRS）强度,但盐酸氯丙嗪本身的RRS强度十分微弱,当二者共存时,溶液的RRS强度显著增强并出现新的RRS光谱,在280～368 nm之间产生强烈的散射带,其最大散射波长位于368 nm,并在284、440、498 nm处有明显的散射峰。在一定条件下,盐酸氯丙嗪在0～0.08 mg/L范围内与ΔIRRS强度成正比,方法具有较高的灵敏度,对盐酸氯丙嗪的检出限（3σ）达到1.75μg/L。本文考察了反应体系的RRS光谱特征,研究了适宜的反应条件、影响因素及分析化学性质,研究了共存物质的影响,表明方法具有较好的选择性,据此发展了一种用金纳米微粒作RRS探针测定盐酸氯丙嗪的新方法。

轴向变速黏弹性Rayleigh梁非线性参数振动稳态响应

研究非线性轴向运动黏弹性Rayleigh梁因速度周期变化产生的亚谐波共振。轴向运动速度在平均速度附近做简谐周期性脉动。通过取物质导数的Kelvin本构关系描述Rayleigh梁的黏弹性。运用多尺度近似解析方法,构建轴向运动Rayleigh梁的非线性偏微分方程的可解性条件,分析参数振动稳态响应的振幅与扰动速度频率关系。并运用微分求积方法直接离散非线性Rayleigh梁的控制方程,以验证近似解析方法分析。通过数值算例,分析了系统参数对稳态响应曲线的影响。

Zn(Ⅱ)-硫氰酸盐-人血白蛋白体系共振Rayleigh光散射增强法对水环境Zn(Ⅱ)的测定

研究了Zn(SCN)24-配合物与人血清白蛋白结合的散射光谱。结果发现,Zn(SCN)24-的加入导致体系共振Rayleigh光散射增强;在一定条件下,600 nm处峰增强程度与Zn(Ⅱ)量成线性关系。据此建立了共振Rayleigh光散射增强法检测痕量Zn(Ⅱ)的新方法。方法线性范围0.005~1.0 mg/L,线性回归方程ΔIRRS=5.20+308.21ρZn(Ⅱ),相关系数r=0.9996,检出限1.5μg/L,RSD为1.5%~3.3%,加标回收率为95%~103%。该方法结果与原子吸收法基本吻合。

小檗碱-四苯硼钠缔合纳米微粒体系的共振Rayleigh散射光谱及其分析应用

目的 研究 (小檗碱 四苯硼钠 ) n 缔合纳米微粒的形成与共振Rayleigh散射之间的关系 ,建立测定小檗碱的共振Rayleigh散射光谱分析新方法。方法 采用共振Rayleigh散射光谱法、吸收光谱和透射电镜研究四苯硼钠(TPB)与盐酸小檗碱 (BB)的缔合反应。结果 在pH 5 0NaAc HAc缓冲溶液中 ,TPB与BB结合形成的 (BB TPB) n 缔合纳米微粒在 4 70nm处产生一个共振Rayleigh散射 (RRS)峰。建立了测定 0 0 6～ 5 2 8mg·L- 1 盐酸小檗碱的RRS新方法 ,检出限为 2 6 μg·L- 1 。结论 通过TPB- 与BB+ 和Ag+ 反应形成可用透射电镜观测的 (BBjAgp TPBj +p) h 复合缔合纳米微粒 ,证实了固液界面的形成是导致其共振Rayleigh散射光增强的充分必要条件。建立的RRS新方法可用于中成药中微量小檗碱的测定 ,具有灵敏度高 ,试样用量少等特点。

轴向变速粘弹性Rayleigh梁参数共振稳定性

运用近似解析方法和数值方法研究轴向变速运动黏弹性Rayleigh梁的次谐波共振和组合共振的稳定性区域。基于变分原理,考虑梁断面旋转惯性的影响,推导轴向速度有周期波动的微变形梁横向振动的数学模型;采用多尺度方法建立前两阶次谐波共振和组合共振范围内的参数振动的可解性条件;进而确定梁两端简支边界条件下,因共振而产生的失稳区域;通过微分求积方法求解表征细长Rayleigh梁横向振动的运动微分方程。数值算例分析了黏弹性系数和扭转系数对梁振动失稳区域的影响,将数值仿真结果与近似解析方法的结论进行比较。算例表明:近似解析解的精度较高,第一、第二阶主共振的最大误差分别为3.206%、4.213%。

一种三环并联Rayleigh后向散射式光纤转动传感器

以单环后向Rayleigh散射式光纤转动传感器原理为基础,提出了一种三环形腔并联Rayleigh后向散射式光纤转动传感器新结构.利用三个2×2单模光纤耦合器,建立了并联三环形腔Rayleigh后向散射式光纤转动传感器的理论模型,给出了用光时域反射计(OTDR)探测到的信号强度表达式.通过计算机仿真优化了参量,选择三环的长度分别为1500m、1078m和680m.三个2×2光纤耦合器的耦合系数分别为95.23%、94.88%和95.26%构建了测试系统,对不同转速所探测到的后向Rayleigh散射信号进行测量,得到与理论相一致的实验结果.三环的采用,增加了测试的有效数据,使其更有利于识别,提高了测量转速的准确度.

汞(Ⅱ)-邻菲罗啉-曙红Y体系共振Rayleigh散射光谱法测定水样中的痕量汞

研究了汞(Ⅱ)-邻菲罗啉-曙红Y体系的光谱特征,并考察了体系的最佳反应条件、灵敏度、选择性.结果表明,该方法具有较高的灵敏度和较好的选择性,检出限可达2.18ng·mL^(-1).据此,提供了一种用RRS技术,灵敏、简便、快速测定Hg(Ⅱ)的方法.

庆大霉素-刚果红体系共振Rayleigh散射光谱的研究及其分析应用

目的建立一种测定痕量庆大霉素的方法。方法在pH6.37的Britton-Robinson缓冲液中,将刚果红与庆大霉素反应的离子缔合物在荧光光度计上进行同步扫描(λem=λex),得到体系的共振Rayleigh散射光谱。在最强散射波长处,研究体系适宜的反应条件和影响因素。结果庆大霉素浓度在0.03～4.06μg/mL范围内与散射强度呈良好的线性关系,其回归方程为△I=12.53c–1.237(μg/mL,R=0.9985)),方法的检出限为12.13ng/mL。结论该法操作简便,灵敏度高,已用于硫酸庆大霉素注射剂的快速检测,结果满意。

酸性磺酞类染料共振Rayleigh散射光谱法测定奈替米星

用共振Rayleigh散射(RRS)光谱研究了酸性磺酞类染料溴甲酚绿和溴酚蓝分别与奈替米星的相互作用.溴甲酚绿和溴酚蓝在酸性介质中分别与奈替米星相互作用,导致RRS光谱显著增强,最大的RRS峰分别位于606nm和572nm处,散射强度与奈替米星的质量浓度在一定的范围内成正比.此方法具有很高的灵敏度,对于奈替米星的检测限(3σ)分别为30ng/mL和10ng/mL,据此发展了一种测定奈替米星的新方法.

Effect of rotary inertia on stability of axially accelerating viscoelastic Rayleigh beams

The dynamic stability of axially moving viscoelastic Rayleigh beams is pre- sented. The governing equation and simple support boundary condition are derived with the extended Hamilton＇s principle. The viscoelastic material of the beams is described as the Kelvin constitutive relationship involving the total time derivative. The axial tension is considered to vary longitudinally. The natural frequencies and solvability condition are obtained in the multi-scale process. It is of interest to investigate the summation parametric resonance and principal parametric resonance by using the Routh-Hurwitz criterion to obtain the stability condition. Numerical examples show the effects of viscos- ity coefficients, mean speed, beam stiffness, and rotary inertia factor on the summation parametric resonance and principle parametric resonance. The differential quadrature method （DQM） is used to validate the value of the stability boundary in the principle parametric resonance for the first two modes.

Triad resonant wave interactions in electrically charged jets

Nonlinear instability in electrically charged jets is studied using the governing electro-hydrodynamic equations describing stretching and thinning of a liquid jet. A jet flow system subject to both space and time evolving disturbances is considered. At the linear stage, the Rayleigh and conducting jet flow instability modes are uncovered.Nonlinear instability in the flow is explored via triad resonant waves which uncover favorable operating modes not previously detected in the linear study of the problem. In particular, the jet radius is significantly reduced, and the electric field of the jet is properly oriented under the nonlinear study. It is found that taking into account the resonance triad modes provides a better mathematical description of a jet that stretches and thins due to tangential electric field effects. Both linear and nonlinear instability results in the jet flow system are presented and discussed.

变张力轴向运动Rayleigh梁组合参激共振的稳态响应

研究非线性轴向变速黏弹性Rayleigh梁的参激振动问题。梁的本构关系使用Kelvin黏弹性模型描述,并且取全导数。基于广义哈密顿原理,导出轴向运动Rayleigh梁的非线性控制方程。考虑轴向速度在平均速度的基础上有简谐变化。运用直接多尺度法近似求解控制方程,并考虑轴向速度变化频率接近任意两阶固有频率之和时而发生的组合参激共振。依据可解性条件,得到振幅频率方程。通过对数值例子的分析,得到梁的刚度、扭转刚度以及平均速度对稳态响应的影响。

Resonance Rayleigh scattering spectral characteristics of interaction of nucleic acids with some cationic surfactants and their analytical applications

In near neutral medium, the resonance Rayleigh scattering (RRS) intensities of an alone cationic surfactant and nucleic acid are very weak. However, when they combine with each other to form a complex, the RRS intensity of the solution is enhanced greatly. In this paper the reactions of five cationic surfactants with nucleic acids have been studied. The results show that the reaction conditions and RRS spectral characteristics of these reactions are similar, but their sensitivities are obviously different. Among them, the sensitivity of cetyldimethyl benzylammonium chloride (CDBAC) with an aryl and large molecular weight is the highest, while that of cetyltrimethylammonium bromide (CTAB) without aryl and with small molecular weight is the lowest. The detection limits for ctDNA and yRNA of the former are 6.6 and 29.4 ng@mL?1, while that of the latter are 13.3 and 53.6 ng@mL?1. The method has better selectivity and can be applied to the determination of trace amounts of nucleic acids. Furthermore, it is discovered in the investigation that not only the RRS intensity is related to the structure and molecular weight of the cationic surfactants, but also the change of the RRS intensity is closely related to the conformational change of nucleic acid. Therefore, the RRS method can be expanded to become a useful way to study the nucleic acid conformation.