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1.
在 p H=3.5的乙酸 -乙酸钠缓冲溶液中 ,用中性红褪色光度法测定了蒙药铜灰体系中产生的过氧化氢的含量。过氧化氢在 0— 5 0μg/ 2 5 m L范围内与 lg(A0 / A)值呈线性关系 ,线性回归方程为 lg(A0 / A) =2 .5× 10 -3+1.0 5× 10 -2 C双氧水 (μg/ 2 5 m L) ,r=0 .9999  相似文献   

2.
毕韶丹  张欣 《光谱实验室》2004,21(3):582-584
在 p H5 .0的乙酸 -乙酸钠缓冲溶液和聚乙烯醇体系中 ,钴 ( )和镍 ( )可与 PAN试剂形成稳定的络合物。以钴 ( )的 5 80 nm和 6 2 6 nm为测定波长对 ,镍作标准加入组分 ,双波长标准加入法可同时测定试样中钴、镍的含量。镍在 0— 15 μg/2 5 m L,钴在 0— 10 μg/2 5 m L范围内遵从比耳定律。对镀液样品进行测定 ,镍、钴的相对标准偏差 (n=6 )分别 <0 .82 %和 <1.2 %。  相似文献   

3.
5-溴水杨基荧光酮荧光光度法测定微量铬(Ⅵ)   总被引:6,自引:0,他引:6  
本文以 5 -溴水杨基荧光酮 (5 - Br SAF)为荧光试剂 ,利用 Cr( ) - 5 - Br SAF- CPB三元配合物的形成使5 - Br SAF- CPB体系荧光熄灭的效应 ,建立了测定微量 Cr( )的荧光分析新方法。研究了最佳的测试条件 ,其激发波长和发射波长分别为 36 5 nm和 5 2 6 nm,反应的适宜酸度范围为 0 .0 16— 0 .0 80 mol·L-1盐酸 ,线性范围为 0— 4 .0μg/ 2 5 m L ,方法检出限为 1.2μg/ L。  相似文献   

4.
研究了在 p H5 .5的 Na Ac- HAc介质中 ,铁 ( )、钒 ( )催化溴酸钾氧化邻氨基酚显色的指示反应 ,用萃取平衡控制反应时间和水相中邻氨基酚的浓度及反应程度 ,通过测量 41 8nm处有机相的吸光度 ,建立了萃取催化动力学光度法同时测定痕量铁 ( )、钒 ( )的新方法。测定铁 ( )、钒 ( )的线性范围分别为 0 .0 5 - 2 0 μg/L和 0 - 1 0 0 μg/L;检出限分别为 3.2× 1 0 - 7g/L和 1 .3× 1 0 - 6g/L。用于测定环境水样及废水中的铁 ( )、钒 ( ) ,结果与 AAS法相符。  相似文献   

5.
采用高效液相色谱法测定盐酸二氧异丙嗪的含量。色谱柱为 DIKMATMRPC18(4 .6 mm× 2 0 cm,5 μm) ,流动相为乙腈 - 0 .5 %磷酸二氢钾 -三乙胺 (5 0∶ 5 0∶ 0 .2 ) ,用磷酸调 p H值至 6 .8± 0 .1;流速为1.0 m L/ min,检测波长为 2 6 4nm。该法回收率为 99.6 % ,RSD=0 .6 1%。盐酸二氧异丙嗪在浓度为0 .0 184 8— 0 .0 4 312 mg/ m L范围内线性关系良好。相关系数为 r=0 .9999。该方法操作简便 ,结果准确可靠。  相似文献   

6.
ZORBAX Eclipse XDB- C8(4.6× 1 5 0 mm,5 μm)色谱柱 ,乙腈流动相 ,流速 0 .6 0 m L/min,检测波长4 2 0 nm,反相高效液相色谱法测定 1 - (4-硝基苯 ) - 3- (5 -溴 - 2 -吡啶 ) -三氮烯。该法的线性范围为 1—1 0 .0 μg/m L,线性回归方程为 A=5 .91 5 4 .4 37C,相关系数 0 .9989,相对标准偏差为 0 .8973%(C=7.2 0 μg/m L,n=5 ) ,检出限为 0 .0 2 872 μg/m L,平均回收率在 93.2 %— 1 0 2 .2 %之间。  相似文献   

7.
研究发现在碱性条件下,依诺沙星对Luminol-H2O2-四磺基锰钛菁(MnTSPc)体系的化学发光有较强的抑制作用,据此建立了流动注射化学发光测定依诺沙星药物的新方法.依诺沙星浓度在2.0×10-8-5.0×10-5mol/L范围内与发光信号的降低值(△I)呈良好的线性关系;检出限(3δ)为7.9×10-9mol/L;对于1.0×10-6mol/L依诺沙星进行11次测定,相对标准偏差为1.31%.应用于片剂中依诺沙星含量的测定,结果令人满意.  相似文献   

8.
Meso-5,10,15,20-四(4-甲氧基苯基)卟啉荧光熄灭法测定铅   总被引:3,自引:0,他引:3  
基于铅对荧光试剂 Meso- 5 ,10 ,15 ,2 0 -四 (4 -甲氧基苯基 )卟啉 (TMOPP)的荧光熄灭 ,建立了测定微量铅的荧光分析方法。在 p H9.5的 Tris- HCl缓冲体系中 ,最大激发波长和发射波长分别为 4 2 4 nm和6 5 7nm,测定铅浓度的线性范围为 5 .5 0× 10 -7— 7.5 0× 10 -5mol/ L,检出限为 8.5 0× 10 -8mol/ L。用于环境水样中铅含量的分析 ,结果满意。  相似文献   

9.
催化动力学光度法测定乙醛催化剂中的微量钯   总被引:1,自引:0,他引:1  
基于 p H 5 .5 0的乙酸 -乙酸钠介质中 Pd( )催化次磷酸钠还原结晶紫的褪色反应 ,建立了测定微量钯的催化动力学光度法 ,研究了最佳反应条件和动力学参数。方法的检出限为 4 .7× 1 0 -9g Pd( ) /m L,线性范围为 0— 0 .8μg/2 5 m L,表观摩尔吸光系数为 7.6× 1 0 5L· mol-1· cm-1,用于测定乙醛催化剂中的微量钯 ,取得满意结果  相似文献   

10.
光泽精化学发光体系的研究与应用   总被引:5,自引:0,他引:5  
李光浩 《光谱实验室》2002,19(6):736-740
对光泽精化学发光体系的动力学性质、荧光光谱、化学发光光谱及化学发光机理进行研究和探讨。详细研究了光泽精 - H2 O2 - Co( )流动注射化学发光体系的最佳分析条件。结果表明 ,当光泽精 (L c)为 2 .5×10 - 5mol/L、H2 O2 为 0 .5 mol/L、Na OH为 0 .4 mol/L、CTMAB为 2 .0× 10 - 5mol/L时 ,测定 Co( )的校准曲线线性范围为 0 .0 5— 2 0 0μg/m L ,检出限为 0 .0 1μg/m L。对 10μg/m L Co( )连续测定 7次 ,相对标准偏差为 1.7%。  相似文献   

11.
A multi-conjugate adaptive optics (MCAO) can offer a possibility of widening field of view (FOV) characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle's expressions of two deformable mirrors (DMs) MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.  相似文献   

12.
Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.  相似文献   

13.
14.
Characterization of PolyA and PolyC mismatches by Raman spectroscopy   总被引:1,自引:0,他引:1  
A.C mismatches are studied by Raman spectral characterization of PolyA, PolyC, and their equimolar complex in solution of 0.14 mol/L Na ,pH7.0.Experimental results show that A·C mismatches occur to be A/B (mainly A) conformers, and unlike Watson-Crick base pairing, this kind of mismatches is stabilized by only one hydrogen bond involving cytosine N4H2 and adenine N7.The formation of A·C complex makes the base stacking interactions much stronger, and conformation of the backbone more ordered, which leads to obvious Raman hypochromic effect with some shifts in corresponding bands.  相似文献   

15.
40-GHz clock modulated signal as a pump to improve the efficiency of four-wave mixing (FWM)-based wavelength conversion in a 26.5-km dispersion shifted fiber (DSF) is investigated. The experimental results demonstrate that the conjugated FWM component has higher intensity with the clock pumping than that with the continuous-wave (CW) light pumping. The improvement of FWM-based wavelength conversion efficiency is negligible when the pump power is less than Brillouin threshold. But when the pump power is greater than Brillouin threshold, the improvement becomes significant and increases with the increment of pump power. The improvement can increase up to 9 dB if pump power reaches 17 dBm.  相似文献   

16.
Multi-pulse operation of a Kerr-lens mode-locked femtosecond laser   总被引:2,自引:0,他引:2  
Our experimental results show that the presence of a proper amount of negative group velocity dispersion is essential to multi-pulse operation of a Kerr-lens mode-locked femtosecond laser. We demonstrate that the pulse separations and the number of pulses contained within a cavity round trip are strongly dependent on the initial perturbations. The results allow us to get a better understanding on the influences of the convoluted self-phase modulation and intra-cavity dispersions on the stable multi-pulse oscillation in a Kerr-lens mode-locked femtosecond laser.  相似文献   

17.
Propagation of Helmholtz-Gauss beams in weak turbulent atmosphere   总被引:1,自引:0,他引:1  
Based on the Rytov approximation of light propagation in weak turbulent atmosphere,the closed-form expressions of field and average irradiance of each one of the four fundamental families of Helmholtz-Gauss (HzG)beams:cosine-Gauss beams,stationary Mathieu-Gauss beams,stationary parabolic-Gauss beams,and Bessel-Gauss beams,which are propagating in weak turbulent atmosphere,are obtained.The results show that the field and average irradiance can be written as the product of four factors:complex amplitude depending on the z-coordinate only,a Ganssian beam.a factor of complex phase perturbation induced by atmospheric turbulence,and a complex scaled version of the transverse shape of the non-diffracting beam.The effect of weak atmospheric turbulence on irradiance distribution of the HzG beam can be ignored.  相似文献   

18.
An effective method for reducing speckle noise in digital holography   总被引:1,自引:0,他引:1  
An effective method for reducing the speckle noise in digital holography is proposed in this paper.Different from the methods based on classical filtering technique,it utilizes the multiple holograms which are generated by rotating the illuminating light continuously.The intensity images reconstructed by a series of holograms generated by rotating the illuminating light possess different speckle patterns.Hence by properly averaging the reconstructed intensity fields,the speckle noises can be reduced greatly.Experimental results show that the proposed method is simple and effective to reduce speckle noise in digital holography.  相似文献   

19.
Influence of purity of HfO2 on reflectance of ultraviolet multilayer   总被引:1,自引:0,他引:1  
The impurities in two kinds of HfO2 materials and in their corresponding single layer thin films were determined through glow discharge mass spectrum technology and secondary ion mass spectrometry(SIMS) equipment respectively.It was found that ZrO2 was the main impurity in the two kinds of HfO2 either in the original HfO2 materials or in the electron beam deposited films.In addition,the difference of Zr content in the two kinds of HfO2 single laver films was much laxger than that of the other impurities such as Ti and Fe.which showed that it was just ZrO2 that made the difference between the optical performance of the film products including the two kinds of HfO2.With these two kinds of HfO2 and the same kind of SiO2.we deposited HfO2/SiO2 multilayer reflective coatings at the wavelength of 266 nm.Experimental results showed that the reflectances of these two mirrors were about 99.85% and 99.15% respectively,which agreed well with the designed results what were based on the optical constants obtained from the corresponding single layer thin films.  相似文献   

20.
Microphone array-based speech enhancement has great importance for speech communications and speech recognition. To reduce the aperture of the microphone array and to increase the effect of the speech enhancement will greatly broaden the application areas of the microphone array. An array crosstalk resistant adaptive noise cancellation method is therefore presented. And then an improved spectral subtraction algorithm is further cascaded to obtain better enhancement results. Theoretic analysis and experiments indicate that the proposed scheme needs only a very small microphone array while it simultaneously achieves a higher SNR improvement. Besides, the proposed scheme can be used in many noisy environments and is easy for real-time implementation.  相似文献   

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