ICP—AES法直接测定高纯Eu2O3中14种稀土元素

建立了ＩＰＣ－ＡＥＳ测定高纯Ｅｕ２Ｏ３中１４种稀土元素的方法，用正交设计法优化仪器测量条件，实验了基体Ｅｕ２Ｏ３对被测元素的干扰和对方法测定下限的影响。１４个稀土元素的测定下限为：Ｙｂ２Ｏ３０．５μｇ．ｇ＾－１，Ｙ２Ｏ３１μｇ．ｇ＾－１，Ｄｙ２Ｏ３，Ｈｏ２Ｏ３，Ｔｍ２Ｏ３和Ｎｄ２Ｏ３５μｇ．ｇ＾－１、Ｇｄ２Ｏ３、Ｓｍ２Ｏ３、Ｅｒ２Ｏ３、Ｃｅ２Ｏ３、Ｐｒ６Ｏ１１和Ｌａ２Ｏ３１０μｇ．ｇ＾－１，Ｌｕ２     

激光蒸发进样ICP－AES测定地质祥品中的钡和锶

本文讨论了用连续ＣＯ＿２激光器蒸发地质粉末样品，ＩＣＰ－ＡＥＳ测定Ｂａ和Ｓｒ。在样品中加入适量的粘合剂和石墨粉混匀压饼，用激光全部蒸发。在蒸发室出口处加入了一只多层多孔过滤器，一定程度上改善了系统长时间工作的稳定性。对影响激光采样和ＩＣＰ－ＡＥＳ分析性能的参数进行了研究。实验结果表明，连续激光蒸发地质粉末样品、ＩＣＰ－ＡＥＳ测定Ｂａ、Ｓｒ，大部分分析结果满意。在选择的系统条件下，Ｂａ、Ｓｒ的检出限分别为２．６μｇ·ｇ￣－１和３．０μｇ·ｇ￣－１；精密度ＲＳＤ分别为６．３％（４７０μｇ·ｇ￣－１）和５．６％（５２μｇ·ｇ￣－１）     

超声雾化空气－氩ICP－AES的检出限

医用超声雾化器改装后作为ＩＣＰ－ＡＥＳ的进样装置。在高频功率３．８×０．８０ｋＷ，载气流量０．８０Ｌ·ｍｉｎ（－１），观察高度１．０ｃｍ的折衷条件下，测定了２７种元素的检出限，１５种稀土元素中Ｄｙ、Ｅｕ、Ｈｏ、Ｙ和Ｙｂ的检出限低于１μｇ·Ｌ（－１）。     

铜与2-羟基-3-羧基-5-磺酸基苯重氮氨基偶氮苯反应的分光光度法研究及应用

研究了铜与２－羟基－３－羧基－５－磺酸基苯重氮氨基偶氮苯（ＨＣＳＤＡＡ）的显色反应。在Ｔｒｉ－ｔｏｎＮ－１０１存在下和ｐＨ１０．４～１１．５的缓冲介质中，Ｃｕ２＋与ＨＣＳＤＡＡ形成１∶２的红色配合物，其最大吸收波长是５３０ｎｍ，对比度为１０２ｎｍ，表观摩尔吸光系数为１．３１×１０５Ｌ·ｍｏｌ－１·ｃｍ－１。铜在０～０．２４μｇ／ｍＬ范围内服从比尔定律。用于铅锌矿和花生中微量铜的测定，相对误差不大于３．７％，相对标准偏差不大于１．６％（ｎ＝６）。     

新间接紫外光度法测定微量SO3^2—

在ｐＨ７．０混合磷酸盐介质中,ＳＯ３＾２－使Ｉ３＾－与ＣＴＭＡＢ生成离子缔合物ＣＴＭＡ＾＋,Ｉ３＾－而褪色,从而建立了测定ＳＯ３＾２－的新间接紫外光度法,测定波长为３６５ｎｍ,ＳＯ３＾２－浓度在０－２５μｇ／２５ｍＬ内服从比耳定律,表观摩耳吸光系数为ε＝６．０４×１０＾４Ｌ·ｍｏｌ＾－１·ｃｍ＾－１,可用于食品中微量ＳＯ３＾２－的测定,其结果满意。     

析相光度法测定铜（Ⅱ）的研究

本文研究了Ｃｕ－ＰＥＧ－ＤＤＴＣ（铜试剂）（ＮＨ４）２ＳＯ４体系的析相光度法并应用于测定Ｃｕ。最宜酸度为３．６－９．０（ＮａＡｃ－ＨＡｃ，ＮＨ４Ｃｌ－ＮＨ３．Ｈ２Ｏ）缓冲溶液，其络合物的最大吸收位于４５０ｎｍ，表观摩尔吸光系数为９．０５×１０＾３Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，Ｃｕ浓度在０－３０μｇ／Ｌ范围内服从比耳定律，铜与ＤＤＴＣ形成组成为１：２的稳定络合物。该方法用于铝合金中铜的测定，获得了满     

巯基棉分离富集原子吸收光谱法测定铜精矿中金银

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％。     

铂(Ⅳ)-钼酸盐-乙基罗丹明B离子缔合显色反应研究

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。     

ICP-AES法分析Au-Be合金

研究了用ＩＣＰ－ＡＥＳ法测定Ａｕ－Ｂｅ合金中Ｂｅ及萃取Ａｕ后测定微量Ｐｔ、Ｐｄ、Ｒｈ、Ｉｒ、Ａｇ等２５个杂质元素的方法。元素间的干扰用等效浓度法校正。杂质元素标准加入回收率为９６－１０７％,相对标准偏差为１．７－１２％。取２．５ｇ试样时相对分析下限为１×１０＾－４－５×１０＾４％。测定合金成分Ｂｅ时相对误差不大于２％。     

银－2－羧基－4－溴苯基重氮氨基偶氮苯－Triton X－100－SDS显色体系的研究及应用

新三氮烯类试剂之一，２－羧基－４－溴苯基重氮氨基偶氮苯，在ｐＨ１１．０的Ｎａ_２Ｂ_４Ｏ_７－ＮａＯＨ缓冲介质中，有非离子表面活性剂ＴｒｉｔｏｎＸ－１００及阴离子表面活性剂ＳＤＳ的共同存在下，可与Ａｇ（Ⅰ）生成稳定的２∶１红色配合物，红色配合物的λ_（ｍａｘ）＝５４０ｎｍ，表观摩尔吸光系数ε_（５４０）＝１．１０×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）。Ａｇ量在０－１０μｇ／２５ｍＬ符合比尔定律。方法用于工业废水中痕量Ａｇ的测定，结果满意。     

Theoretical analysis and simulation of conjugate heights for dual-conjugate AO system in lidar

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.     

Quick single-photon detector with many avalanche photo diodes working on the time division

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.     

Characterization of PolyA and PolyC mismatches by Raman spectroscopy

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.     

Improvement of four-wave mixing-based wavelength conversion efficiency in dispersion shifted fiber by 40-GHz clock pumping

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.     

Multi-pulse operation of a Kerr-lens mode-locked femtosecond laser

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.     

Propagation of Helmholtz-Gauss beams in weak turbulent atmosphere

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.     

An effective method for reducing speckle noise in digital holography

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.     

Influence of purity of HfO2 on reflectance of ultraviolet multilayer

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.     

Speech enhancement by array crosstalk resistant ANC and spectrum subtraction

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.