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1.
多波长线性回归分光光度法同时测定催化剂中钨和钼   总被引:3,自引:1,他引:2  
以水杨基荧光酮(SAF)-溴代十六烷基三甲铵(CTMAB)为显色体系,详细考查了测定条件。采用多波长线性回归分光光度法同时测定了W-Mo-Ni/Al2O3加氢催化剂中的钨和钼。相对标准偏差小于1.6%,合成样品回收率94.0%-106.4%。测定结果与比色法(分别测定)及X-射线荧光光谱法相吻合。  相似文献   

2.
马红燕  王云 《光谱实验室》2000,17(1):100-103
本文报道了在溴化十六烷基三甲铵(CTMAB)存在下,以5-溴水杨基荧光酮(5-BrSAF)作为荧光试剂,用荧光熄灭法测定微量钼的新方法。详细研究了各种条件实验。反应的适宜酸度范围为 0.08-0.24m ol·L- 1 HCl,钼含量在0- 4.0μg/25m L范围内呈线性关系,配合物的组成比为Mo(Ⅵ)∶5-BrSAF∶CTMAB= 1∶2∶2,激发波长为365nm ,发射波长为525nm 。方法灵敏度高,检出限为2.0μg/L。用于样品中微量钼的测定,结果令人满意。  相似文献   

3.
马红燕  王云 《光谱实验室》2000,17(1):100-102,103
本文报道了在溴化十六烷基三甲铵(CTMAB)存在下,以5-溴水杨基荧光酮(5-BrSAF)作为荧光试剂,用荧光熄灭法测定微量钼的新方法。详细研究了各种条件实验。 反应了适宜酸度范围为0.08-0.24mol.L^-1HC1,钼含量在0-4.0ug/25mL范围内呈线性关系,配合物的组成比为Mo(Ⅳ):5-BrSAF:CTMAB=1:2:2,激发波长为365nm,发射波长为525nm。方法灵敏度高,检出  相似文献   

4.
应用ICP-AES法,对核纯海绵锆中17个杂质元素的测定进行了试验研究。取样量100mg时,Al、Ca、Co、Cr、Cu、Fe、Mg、Mn、Mo、Ni、Pb、Sn、Ta、Ti、V、Y和Zn的测定范围是10μg/g-3200μg/g。回收率为95.2%-106.5%。  相似文献   

5.
本文基于Zr(Ⅳ)5‘-硝基-水杨基荧光酮-溴化十六烷基三甲铵(CTMAB)体系的荧光猝灭效应,提出一种测定微量锆的新荧光分析方法。在0.8-1.2--mol/L的H2SO4介质中,CTMAB存在下,锆与5’-N-SAF生成组成比为1:4的橙红色络合物。  相似文献   

6.
应用ICP-AES法,对核纯海绵锆中17个杂质元素的测定进行了试验研究。取样量100mg时,Al、Ca、Co、Cr、Cu、Fe、Mg、Mn、Mo、Ni、Pb、Sn、Ta、Ti、V、Y和Zn的测定范围是10μg/g—3200μg/g。回收率为95.2%—106.5%。  相似文献   

7.
铂(Ⅳ)-钼酸盐-乙基罗丹明B离子缔合显色反应研究   总被引:2,自引:0,他引:2  
本文研究了在聚乙烯醇(PVA)存在下用钼酸盐与乙基罗丹明B(ERB)形成离子缔合物,该缔合物的最大吸收位于580nm,摩尔吸光系数为1.12×106L·mol-1·cm-1,服从比耳定律范围0—2.5μg/25mL,缔合物至少稳定1周,考察了50多种共存离子的影响,除生成杂多酸元素和Au(Ⅲ)、Os(Ⅷ)、Pd(Ⅱ)、Ir(Ⅳ)外,大多数元素不干扰。测定铂的条件为:〔HClO4〕=1.2mol/L,〔MoO42-〕=9.1×10-4mol/L,〔ERB〕=3.2×10-5mol/L,0.08%PVA。缔合物的摩尔比为Pt(Ⅳ)∶ERB=1∶2,本法已用于铂矿中铂的测定,结果满意。  相似文献   

8.
人工神经网络分光光度法同时测定钼和铬   总被引:4,自引:0,他引:4  
在钼,铬-二溴羟基苯基荧光酮-CTMAB显色体系中,应用三层ANN-BP网络解析钼和铬的吸收光谱,不经分离分光光度法同时测定钼和铬。钼和铬的表观摩尔吸光系数分别为ε530=1.4×10^5L·mol^-1·cm^-1,ε512=3.7×10^4L·mol^-1·cm^-1。以合金钢中钼和铬进行了同时测定,结果满意。使用改进的BP算法,避免了神经网络学习过程中可能产生的麻痹现象,提出了目标向量的简单  相似文献   

9.
本实验测定了新型钼(钨)-铁-硫簇合物(1)(Et4N)[MoFe2(μ3-S)2(CO)8(S2CNEt2)和(2)(Et4N)[WFe2(μ3-S)2(CO)8(S2CNEt2]的穆斯堡尔谱和晶体结构。它们分子中的两个铁原子是等价的,所以都只的一组对称的四极分裂双峰。这个结果与单晶结构分析一致。经计算机拟合后的穆斯堡尔参数(77K时)为:对于(1),化学位移δ=0.08±0.004mm/s,四  相似文献   

10.
研究新合成的水溶性光度试剂N-壬基-N‘-(氨基对苯磺酸钠)硫脲与钯的显色反应。结果表明,在pH5.8-6.6的HAc-NaAc缓冲体系中,Pd^2+与NTP形成1:4的黄色水溶性配合后物,CTMAB对反应有明显的增敏作用,配合物的最大吸收波长位于297.6nm,表面摩尔吸光系数ε297.6=1.27×10^5L.mol^-1cm^-1,钯含量在2-11.2μg/25mL范围内服从比尔定律,50种  相似文献   

11.
Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.  相似文献   

12.
A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.  相似文献   

13.
The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.  相似文献   

14.
15.
Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·104 Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.  相似文献   

16.
A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.  相似文献   

17.
A transient suppression method for piezoelectric ceramic transducer is presented. By adding some special pedestal pulses to the original transmitted signal, the transient effects in the output of the transducer can be just precisely transmission by use of a narrowband transducer. canceled, thereby achieving the broadband The experimental results show that the transient responses of the sinusoid pulses and coded signals are suppressed successfully and the acoustic waveforms radiated into the surrounding water are improved significantly.  相似文献   

18.
We experimentally demonstrate amplitude squeezed soliton utilizing intensity-dependent self-phase modulation in an asymmetric Sagnac interferometer.The system.whose components are connected via ferrule connector/physical connection(FC/PC)fiber connectors,constitutes all-fiber configuration to generate squeezed soliton.Soliton amplitude reduction measured by homodyne detection is near 4.0 dB below the shot-noise level.Optimal squeezing fields in both simple and compact all-fiber configuration are obtained.  相似文献   

19.
The(2 1)-dimensional nonlinear Schr(o)dinger(NLS)equation with spatially inhomogeneous nonlinearities is investigated,which describes propagation of light in(2 1)-dimensional nonlinear optical media with inhomogeneous nonlinearities.New types of optical modes and nonlinear effects in optical media are presented numerically.The results reveal that the regular split of beam can be obtained in (2 1)-dimensional nonlinear optical media with inhomogeneous nonlinearities,by adjusting the guiding parameter.Furthermore,the stability of beam regular split is discussed numerically,and the results reveal that the beam regular split is stable to the finite initial perturbations.  相似文献   

20.
In the real-world application of face recognition system, owing to the difficulties of collecting samples or storage space of systems, only one sample image per person is stored in the system, which is so-called one sample per person problem. Moreover, pose and illumination have impact on recognition performance. We propose a novel pose and illumination robust algorithm for face recognition with a single training image per person to solve the above limitations. Experimental results show that the proposed algorithm is an efficient and practical approach for face recognition.  相似文献   

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