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1.
本文提供了一种测定金属硅中B,Fe,Al,Ca,Mn等14个杂质元素的ICP-AES方法,在样品处理过程中,加入适量体积的甘露醇能够抑制B的挥发。用本方法测定了一个国家地球化学标准样(GSR-4),结果令人满意。  相似文献   

2.
纯硒中杂质元素的ICP-AES测定   总被引:1,自引:0,他引:1  
电感耦合等离子体-原子发射光谱同时测定纯硒中的碲、铅、铋、锑、铜、铁、镍、铝、锡、砷和硼12种元素的含量,优化出各元素的分析波长和分析条件;用基体匹配补偿基体效应,方法简单,快速可靠,样品回收率为94%-107%.  相似文献   

3.
本文研究了贵金属标准溶液除氯离子的有关问题,解决了高纯硝酸银中贵金属等杂质元素的标样配制,以硝酸银直接压样于普通电极中直流电弧激发,可测定99.0~99.99%的高纯银,该方法简便、快速、准确。  相似文献   

4.
ICP—AES法测定铁矿中铝,钙,镁,锰,钴,铜,钠和钾   总被引:3,自引:0,他引:3  
本文研究了ICP-AES法测定铁矿中铝,钙、镁、锰、钴、铜、钠和钾的方法。对仪器工作参数,共存元素的光谱干扰和基体效应干扰进行了探讨。采用向标准系列中加入铁基空白溶液建立工作曲线,试样经酸处理后即可直接测定。本方法获得了良好的回收率(95~103%)和变异系数(0.5~1.3%,n=11),同原子吸收法进行比对试验,结果一致。  相似文献   

5.
梁亚群 《光谱实验室》1998,15(5):101-104
本文介绍了电感耦合等离子体发射光谱法(ICP-AES)测定高纯铼酸铵中12个杂质元素的方法。采用挥发健康基体,探讨了高铼酸铵基体的干扰及其消除办法。ICP-AES测定结果的准确度和精密度均能满足分析要求。  相似文献   

6.
杨艳  余卫华  张穗忠 《光谱实验室》2009,26(5):1100-1104
用X射线荧光光谱法测定了不锈钢中Si、Mn、P、Cu、Ti、W、Mo、V、Ni、Cr、Nb等11种元素的含量。对磨样条件、准确度和精密度进行了实验,实验表明本方法与化学法所测结果相符。  相似文献   

7.
Hugo O. Mosca 《Surface science》2007,601(15):3224-3232
The surface energy for different surface orientations of the solid solutions as a function of concentration formed by Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W is computed and analyzed using the BFS method for alloys. Similarities and differences among the different binary alloys are examined in terms of strain and chemical effects.  相似文献   

8.
New results concerning the statistics of, in particular,p random walkers on a line whose paths do not cross are reported, extended, and interpreted. A general mechanism yielding phase transitions in one-dimensional or linear systems is recalled and applied to various wetting and melting phenomena in (d=2)-dimensional systems, including fluid films and p×1 commensurate adsorbed phases, in which interfaces and domain walls can be modelled by noncrossing walks. The heuristic concept of an effective force between a walk and a rigid wall, and hence between interfaces and walls and between interfaces, is expounded and applied to wetting in an external field, to the behavior of the two-point correlations of a two-dimensional Ising model belowT c and in a field, and to the character of commensurate-incommensurate transitions ford=2 (recapturing recent results by various workers). Applications of random walk ideas to three-dimensional problems are illustrated in connection with melting in a lipid membrane model.Based on the Boltzmann Medalist address presented at the 15th IUPAP International Conference on Thermodynamics and Statistical Mechanics, Edinburgh, July 1983.  相似文献   

9.
Electrical explosion of wires (EEW) is a promising method for nanopowders preparation and insensitive explosives ignition. Plasma radiation plays a key role in the ignition process while little attention has been paid on this phenomenon before. This letter introduces optical emission behaviors of electrical explosions for nine materials in air, Helium, and Argon with the SWE-2 platform. Experimental results indicated that the light intensity for non-refractory metals decayed rapidly after the discharge ended. In contrast, for refractory metals, the emission continued to increase and lasted for a long period after the discharge ceased. As for spectra, the emission consisted of line and continuous spectra. With the atomic number increased, the density of lines grew rapidly, leading to a “continuous” appearance.  相似文献   

10.
ICP—AES法直接测定锡锭中的As,A1,Bi,Cd,Cu,Fe,Pb,Se,Sb,Zn   总被引:4,自引:0,他引:4  
以电荷耦合器件为检测器的全谱直读等离子体光谱仪直接测定锡锭中As、A1、Bi、Cd、Cu、Fed、Pb、Se、Sb、Zn十种杂质元素的含量。该方法简便、快速且具有比化学法更低的检出限,加标回收试验结果不明,回收率为92%-105%,RSD均小于1.5%。  相似文献   

11.
原子吸收光谱法测定桃叶中K,Mg,Sr,Fe,Cu,Mn和Zn等元素   总被引:2,自引:0,他引:2  
本文采用桃叶作标准样品,讨论了湿法消化法与炭化-灰化法两种样品处理方法对测定结果的影响及方法操作效果比较,并进一步讨论了温度对炭化-灰化法的影响情况。由此建立起该法的适宜条件。在此条件下,用原子吸收光谱法测定桃叶及冷杉树枯枝、叶中多种元素。其精密度和准确度均能满足测定要求。  相似文献   

12.
《Physics letters. A》1997,229(4):259-261
Positron lifetime and Doppler broadening of the annihilation line measurements have been performed at room temperature in high-Tc superconductors RBa2Cu3Oy, where R: La, Nd, Sm, Eu, Gd, Dy, Ho, Y, Er and 6.9 < y ≤ 7. Doppler broadening of the annihilation line measurements have also been performed in high-Tc superconducting samples R RBa2Cu3Oy, where R: Nd, Sm, Eu, Ho, Y, Er as a function of temperature between 14 K and 293 K. It was observed that the positron lifetime and the S parameter values at room temperature have no obvious trend in their variation from the yttrium substitution by a rare-earth element. It was also observed that the temperature dependence of the positron annihilation parameters is similar in the high-Tc superconducting samples.  相似文献   

13.
本文以50ml比色管作消化容器,硝酸-高氯酸混酸消化中成药阿胶,采用火焰原子吸收法测定其中的铜;石墨炉法测定其中的铬、镉、铅;氢化物法测定其中的砷、锑、锡。以硝酸-硫酸加过氧化氢水浴加热消化处理样品、采用冷原子法测定其中的汞,均取得较满意的结果。  相似文献   

14.
ICP-AES同时测定铝合金中Fe,Si,Cu,Mg,Mn,Ni,Zn,Ti,Cr,Sr等杂质元素   总被引:13,自引:0,他引:13  
本文通过基体干扰和操作条件的试验研究,分别用基体匹配法和干扰系数法校正基体干扰和待测元素间的干扰,建立了以氢氧化钠溶样,ICP-AES同时测定铝合金中铁、锰、铜、锌、镁、钛、硅、镍、铬、锶等杂质元素的方法。方法快速、简便、可靠,回收率93%-102%,适用于进出口铝合金的快速检验。  相似文献   

15.
黄晓文  张念  黄小龙 《光谱实验室》2009,26(5):1095-1099
建立碰撞池ICP-MS测定大米中Ca、Mn、Fe、Cu、Ni、As、Se、Sr、Cd、Ba和Hg的分析方法。采用微波消解方法消解样品后直接进行ICP-MS分析,并采用碰撞池技术消除质谱干扰,混合内标溶液校正基体干扰和漂移。方法的精密度均小于5%,回收率为85%—113%,并对标准物质(大米)GBW 10010GSB-1进行方法验证,获得较满意的结果。本法快速、简单,能满足大米中常量、微量、痕量金属元素同时测定的分析需求。  相似文献   

16.
The lowest absorption band of the tetraphenyl compounds resembles that of the lowest absorption band of benzene with the following difference. In benzene the electronic origin is strictly forbidden, and all intensity is associated with a symmetric progression built on one mode of asymmetric vibration. In the tetraphenyl compounds the intensity associated with the asymmetric vibration is relatively unaffected; however, there is increasing intensity associated with the electronic origin and a symmetric progression built on it along the series
φ4Pb < φ4Sn < φ4Ge < φ4Si < φ4C ? φ4B? < φ4Sb+ < φ4As+ < φ4P+
. For the cations it is the electronic origin and the progression built on it that are the primary source of intensity. This effect is attributed to an inductive perturbation. A similar effect is observed in the fluorescence spectrum. In phosphorescence, the relative enhancement of the electronic origin and the progression built on it is far less marked. The phosphorescence emission of φ4Pb and φ4Sb+ are red shifted from the others by ~0.5 eV, an effect attributed to formation of a triplet excimer. Increasing spin-orbit coupling in the triplet due to a heavy atom effect can be seen in the decreasing phosphorescence lifetime (range 4 sec to 4 msec) and decreasing ratio of φfφp (fluorescence to phosphorescence quantum yields) in the order
φ4C > φ4B > φ4Si > φ4P+ > φ4Ge > φ4As+ > φ4Sn
In all cases nonexponential decay of phosphorescence is observed.  相似文献   

17.
The brittle and elastic properties of the B2-MgRE (RE = Sc, Y, Ce, Pr, Nd, Gd, Tb, Dy, Ho, Er) intermetallics have been investigated using first-principles density functional calculations. The calculated equilibrium lattice constants and enthalpies of formation are in overall agreement with the available experiment and theoretical results. The related physical properties of those compounds are compared with that of ductile YCu. The Fermi energy occurs above a peak in the DOS for B2-MgRE intermetallics, whereas for ductile YCu the Fermi energy occurs near a minimum in the DOS. For B2-YCu, the partial density of states of d-states at the Fermi energy is low, while for B2-MgRE the RE d-states are partially occupied, indicating their important roles in the directional bonding for this material. The Cauchy pressure (C12-C44) and the ratio of bulk to shear modulus B/G are used to assess the brittle/ductile behavior of B2-MgRE and YCu compounds. It can be concluded that the B2-MgRE alloys have brittle behavior. MgSc is the most brittle, and MgHo is the least brittle amongst those alloys.  相似文献   

18.
A particle about 50% more massive than a proton, with positive charge, positive strangeness and positive baryon number, has been claimed in several experiments. Such a particle cannot be made from three quarks; its minimal configuration requires four quarks and an antiquark and it became known as a ‘pentaquark’. This article summarizes the evidence and concentrates on the theoretical interest that it has excited into the nature of correlations among quarks and antiquarks in the strong interaction limit of QCD.  相似文献   

19.
The formal structure of quantum information theory is based on the well-founded concepts and postulates of quantum mechanics. In the present contribution, I am inverting the usual approach presented in textbooks by beginning with the use of bit states as basic and fundamental units of information and establish a dynamical map for them. The condition of reversibility, imposed on an ordered sequence of actions operating on a bit state, introduces, by necessity, the unitarity property of actions. I also verify that the uniformity of time, as a parameter for ordering events, is due to the admission of a composition law for the actions. In the limit of infinitesimal intervals between actions, a reversible and linear equation arises for the dynamical changes in time of a qubit (superposition of bit states). The admission that a bit of information is stored or carried by a massive particle necessarily leads to the Schrödinger–Pauli equation (SPE); the bit is associated to a spin 1/2. Within this approach, I verify that the particle dynamical equation becomes “enslaved” by the spin dynamics. In other words, the bit (or spin) precedes in status the particle dynamical evolution, being at the root of the quantum character of the standard Schr¨odinger equation, even when spin and spatial degrees of freedom are uncoupled.  相似文献   

20.
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