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1.
巯基棉分离富集原子吸收光谱法测定铜精矿中金银   总被引:7,自引:0,他引:7  
本文详细地研究了在HCl介质中,巯基棉分离富集Au,Ag,KIO3-HCl解脱Au,原子吸收分光光度法测定金、银的方法。本方法一次溶样连续测定Au,Ag,简便快速,分析结果可靠,在Au32μg,Ag400μg范围内,Au回收率98.8%-101.2%,RSD为3%,Ag回收率97.3% ̄101.3%,RSD为2%。  相似文献   

2.
火焰原子吸收光谱法测定钙盐试剂中的痕量镉   总被引:7,自引:1,他引:6  
张莹  彭茵 《光谱实验室》1999,16(6):671-673
采用巯基棉分离富集钙盐试剂中的前量镉,用火焰原子吸收光谱法进行测定。方法简便、快速,结果满意。样品测定的相对标准偏差均小于4.81%。  相似文献   

3.
本文详细考查了巯基棉富集Fe(Ⅲ)的条件,发现微量铁(Ⅲ)在pH值为5-8的条件下能为巯基棉定量吸附.1mol/L盐酸5mL能将巯基棉吸附的Fe(Ⅲ)定量洗脱,0.1g巯基棉的饱和吸附量为90μg,样品分析测定结果的相对标准偏差小于3.4%,98.4%-98.8%。  相似文献   

4.
本文详细考查了巯基棉富集Fe(Ⅲ)的条件,发现微量铁(Ⅲ)的PH值为5-8的条件下能为巯基棉定量吸附,1mol/L盐酸5mL能将巯基棉吸附的Fe(Ⅲ)定量洗脱,0.1g巯基棉的饱和吸附量为90μg,样品分析测定结果的相对标准偏差小于3.4%,加标回收率为98.4%-98.8%。  相似文献   

5.
张莹  石敏 《光谱实验室》1997,14(6):54-57
偏硼酸钠,无水乙酸钠,无水碳酸钠,磷酸氢二钠等试剂中的痕量镉,经巯基棉分离和富集后,以火焰原子吸收光谱法进行测定。方法简便,快速,测定的相对标准偏差均小于4.61%。  相似文献   

6.
火焰原子吸收光谱法测定食盐中痕量铅   总被引:2,自引:2,他引:0  
滕文锋  杨波  李红 《光谱实验室》2004,21(1):206-208
对巯基棉富集 Pb( )的条件作了研究 ,经过巯基棉分离富集后 ,用火焰原子吸收光谱法测定了食盐中的痕量铅 ,实验回收率 97.3%— 97.5 % ,RSD<5 %。方法简便 ,可用于食盐中痕量铅的测定  相似文献   

7.
滕文锋  彭茵  杨波 《光谱实验室》2004,21(2):402-404
通过巯基棉富集分离后 ,用火焰原子吸收光谱法测定了食盐中的痕量镉 ,研究了巯基棉富集 Cd( )的条件 ,实验回收率 92 %— 98% ,RSD<6 .0 %。本实验方法简便 ,可用于食盐中痕量镉的测定  相似文献   

8.
地质样品中的硒和碲一般郁分散在硫矿物中含量很低,采用巯基棉吸附分离富集硒、碲,用6N 盐酸饱和氯化钠溶液洗涤和干扰分离,巯基棉经王水破坏,在4N 盐酸介质中由氢化法测定硒和碲。  相似文献   

9.
利用巯基棉富集银,将富集银后的巯基棉灰化,用王水将银氧化并控制30%的盐酸酸度,火焰原子吸收光谱法测定卤水中的痕量Ag.对流速、富集时间和酸度等因素进行了实验,方法可用于卤水中痕量银的分析.检出限为(3S/N)=0.002mg/L,加标回收率为99.0%-101%.相对标准偏差为3.21%(n-11).  相似文献   

10.
彭茵  滕文锋 《光谱实验室》2004,21(4):674-676
巯基棉分离富集 ,火焰原子吸收光谱法同时测定钙盐中的痕量铅、镉 ,大量钙不干扰铅、镉的测定。方法简单易行 ,结果令人满意的。  相似文献   

11.
12.
为了提高LED光源色温和亮度的调节精度和准确度,结合色温由低向高变化时光色所呈现的渐变特点,提出了一种低色温白光LED灯珠、高色温白光LED灯珠加红绿蓝光LED灯珠补偿式调光的方法.将色温分成三个部分进行调节,每个部分选用不同的LED灯珠组合来进行调光.实验结果表明:不同组合情况下的LED光源的初始输出色温相对于目标值的偏差范围在1%以内;亮度可以在保证色温不变的情况下独立进行调节,初始输出值与目标值的偏差范围在1%以内;经过微调之后可以达到目标值;达到了色温和亮度独立调节的要求;光源发光稳定,不会因为长时间工作而影响调节精度.  相似文献   

13.
A technique combining image processing and laser interferometry for visualizing and detecting the deformation of transparent cylindrical and spherical sample is proposed. This deformation includes geometric deformation such as volume transition in profilometry and physical deformation such as refractive index change in tomography. Phase contour lines are used for quantitative analysis and graphical representation of the deformation. This method allows us to visually detect the spatial variation of the deformation field and to evaluate the test quality such as misalignment of optical system. A theoretical analysis using phase contour map to characterize the deformation field is described in detail. A method using phase contour map to qualify the interferometric test is proposed. Analysis of test examples is carried out. Suggestions on using phase contour line method to ameliorate test system design are finally discussed.  相似文献   

14.
Discrepancies and accords between quantum (QM) and classical mechanics (CM) related to expectation values and periods are generally found for both the harmonic oscillator (SHO) and a free particle in a box (FPB), which may apply generally. These indicate non-locality is expected throughout QM. The FPB energy states violate the Correspondence Principle. Previously unexpected accords are found and proven that 〈x 2 CM =〈x 2 QM and τ CM =τ QMb (beat period i.e. beats between the phases for adjoining energy states) for the SHO for all quantum numbers, n. However, for the FPB the beat periods differ at small n. It is shown that a particle’s velocity in an infinite square well varies, no matter how wide the box, nor how far the particle is from the walls. The quantum free particle variances share an indirect commonality with the Aharonov-Bohm and Aharonov-Casher effects in that there is a quantum action in the absence of a force. The concept of an “Expectation Value over a Partial Well Width” is introduced. This paper raises the question as to whether these inconsistencies are undetectable, or can be empirically ascertained. These inherent variances may need to be fixed, or nature is manifestly more non-classical than expected.  相似文献   

15.
潘峰  戴连荣 《物理学进展》2004,24(2):216-258
本文总结了计算黑克、布劳、及伯曼 温采尔代数在各种工数链下诱导及分导系数的线性方程方法(LEM)。特别强调了关于A,B,C,D型李代数及其量子情形与其中心代数之间的舒尔 魏尔 布劳双关性关系。这一关系使我们能够利用相应中心代数的诱导及分导系数计算出经典李代数及其量子情形的耦合与重新耦合系数。讨论了从该方法得到B,C,D型李代数不可约表示克罗内克积分解的应用。基于LEM还得到了处理对应于置换群CG系列问题的黑克代数张量积的方法。  相似文献   

16.
国外超导材料技术研究政策和方向   总被引:1,自引:1,他引:0  
超导材料技术是21世纪具有战略意义的高新技术,极具发展潜力和市场前景。世界各发达国家纷纷制定研发计划,给予高度重视和大力支持,加快超导材料技术的基础研究和产业化发展。主要从美国、日本、欧洲国家、韩国等国家的相关研发计划、政策以及主要科研机构的研发概况出发,阐明目前国外超导材料技术的研究政策和方向。  相似文献   

17.
We present a novel method for rapid and flexible laser marking and engraving of tilted, curved and freeform work-piece surfaces. The method is based on integrating a three-dimensional (3D) laser measurement system into a 3D laser marking system. We use the same laser source and optics for measurement and processing with a minimum of additional hardware components. A low power CW laser regime is used to measure the 3D shape of a work-piece surface while a high-peak power-pulsed laser regime is used for processing. The acquired 3D surface data are used to determine the 3D trajectory of the processing beam focus. Neither the 3D shape of the work-piece nor its orientation needs to be known in advance as long as the processed surface lies within the working range of the 3D laser processing system. This eliminates the need for exact work-piece positioning before processing and substantially improves processing flexibility (allowing, e.g. variations in work-piece shape or/and orientation from mark to mark). This paper discusses key issues concerning an implementation of the method and presents typical examples of markings and engravings, which demonstrate the advantages of the method with respect to the existing industrial 2D and 3D laser marking and engraving methods. The method can also be applied to flexible laser structuring and microprocessing of curved surfaces.  相似文献   

18.
We solve several problems that involve imposing metrics on surfaces. The problem of a strip with a linear metric gradient is formulated in terms of a Lagrangian similar to those used for spin systems. We are able to show that the low energy state of long strips is a twisted helical state like a telephone cord. We then extend the techniques used in this solution to two–dimensional sheets with more general metrics. We find evolution equations and show that when they are not singular, a surface is determined by knowledge of its metric, and the shape of the surface along one line. Finally, we provide numerical evidence by minimizing a suitable energy functional that once these evolution equations become singular, either the surface is not differentiable, or else the metric deviates from the target metric.  相似文献   

19.
We present a systematic study of the effect of methyl substitution on iso- and alloxazines in acetonitrile solutions. Substitution patterns have profound effects on both spectral and photophysical properties, with fluorescence quantum yields varying by more than an order of magnitude. TD-DFT calculation were used for the first time to correlate electronic structure changes with the substitution patterns, with good agreement between calculated and theoretical band positions and oscillator strengths. Both n-pi* and pi-pi* states in these compounds are predicted, with the oscillator strengths indicating that only the pi-pi* states should be observable in the absorption spectra. Substitution patterns are shown to be responsible for energy order inversion between these states.  相似文献   

20.
In this letter, we illustrate the importance of fluid dynamics research by considering two particular areas of study: nano- and micro-scale fluid and plasma dynamics. We show how improved scientific knowledge of nano- and micro-fluid dynamics can significantly enhance our future. Application is also discussed regarding environmental aspects.  相似文献   

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