ICP-OES测定月季中矿质元素的五种前处理方法比较

采用五种不同的前处理方法(干灰化法、HNO3+ H2 O2微波消解法、HNO3 +H2O2 +HF微波消解法、HNC3+ HClO4微波消解法、HNO3+ HClO4+HF微波消解法),对月季样品进行消解,利用ICP-OES法测定九种常量和微量元素,加标回收结果显示:HN(3 +HClO4微波消解法是最优的处理方法,对...     

微波消解-火焰原子吸收光谱法测定海藻中的微量元素

利用微波消解-火焰原子吸收光谱法(FAAS)测定了大连产5种海藻样品中Zn、Fe、Cu、Mn 4种微量元素的含量.对微波消解条件和原子吸收光谱测定的条件进行了优化.实验结果表明,微波消解法操作简便快速、样品消解完全,空白值低、环境污染小;火焰原子吸收光谱方法选择性好,准确度高,回收率为91%-105%.样品测定结果显示...     

微波消解-AAS法测定新疆罗布麻叶中的微量元素

微波溶样技术是近年来产生的一种崭新的极有前途的溶样技术.采用微波消解溶样,利用原子吸收法对新疆罗布麻叶中多种微量元素含量进行测定,优化了消化条件.结果表明高压微波消化法具有消解完全、结果准确的优点.     

氢化物发生-原子荧光光谱法同时测定生物体中的Hg和As

建立氢化物发生-原子荧光光谱法同时测定生物体中Hg和As的方法,在最佳的实验条件下,经过平板加热和微波消解样品多次实验比较,常压消解法和微波消解法对标准样品分析的结果均符合要求;其中常压消解法Hg、As的相对标准偏差分别为6.2％和4.0％;微波消解法Hg、As的相对标准偏差分别为4.6％和3.4％.两种方法都能满足海洋生物体中Hg和As含量的测定要求,具有分析速度快、操作简便、检验效率高等特点.     

电热板消解法与微波消解法测定大气颗粒物Cu、Pb元素的对比

采用电热板消解法与微波消解法两种前处理消解方法,测定了青岛小麦岛环境监测站大气颗粒物滤膜样品的Cu、Pb含量,并对测定结果进行了分析对比.发现两种消解方法测定的Cu、Pb含量的分析精密度均较好,只是微波消解法测定值略小于电热板消解法,测定Cu元素时,两种方法不存在显著性差异,可等效使用,而测定Pb元素时,两种方法略存在差异.     

微波消解-火焰光度法测定叶片中钾和钠含量

本文研究了灰化法、常压湿法消解和微波消解3种方法处理植物叶片对火焰光度法测定K、Na含量的影响。结果表明：微波消解法具有消化时间短、样品污染少，测定结果准确，重现性好等特点，加标回收率符合测试要求。     

微波消解-冷原子吸收光谱法测定电池中汞

建立了微波消解 冷原子吸收光谱快速测定电池中汞的分析方法。采用密闭微波酸湿法消解电池样品 ,优化了微波消解条件和仪器测定条件。以HNO3 H2 SO4(φ =4∶1)混合酸作消解液、微波加热 3min ,以0 5mol·L-1H2 SO4为反应介质在室温下测定。方法的特征浓度为 0 2 5 μg·L-1。测定了 5种电池样品 ,回收率在 99 9%～ 113%之间 ,相对标准偏差为 4 9%～ 11 9%。与传统法相比 ,该法具有快速、省试剂、消解完全、汞丢失少等优点。     

ICP-AES测定海产品中的微量元素

对照了湿法消解和微波消解直接消解湿基海产品的方法.采用微波消解样品,电感耦合等离子体-原子发射光谱法（ICP-AES）测定了12种海产品中Zn、Fe、Ca、Mg、Cu和Mn 6种元素的含量,在最佳工作条件下各元素的加标回收率在97.62％-106.0％之间,相对标准偏差（RSD）为0.59％-2.04％,实验结果为研究营养学提供科学依据.     

微波消解-CTAB增敏-HG-ICP-AES法测定中药黄芪中的痕量铅

采用微波消解技术处理样品,建立了CTAB增敏-氢化物发生-电感耦合等离子体发射光谱法(HG-ICP-AES)测定中药黄芪中痕量铅的分析方法。讨论了微波消解试剂、微波消解参数对消解效果的影响,系统地研究了氢化物发生的最佳条件。采用HNO₃+H₂O₂+H₂O为微波消解最佳试剂,在选定的最佳氢化物发生条件下,铅的线性范围为0.23～800 μg·L-1, 相关系数为0.999 9,检出限为0.23 μg·L-1,相对标准偏差为1.02%, 样品加标回收率为98.8%～100.1%。结果表明,微波消解法处理中草药,具有快速、简便、节省试剂、消解完全等特点,测定结果的精密度和准确度令人满意。     

微波消解ICP-AES测定中药朱砂莲中多种元素

采用微波消解 ICP- AES法同时测定了朱砂莲中 Ca、Cu、Fe、K、Mg、Mn、Na、P、Zn等 9种元素 ,加标回收率在 97.3%— 10 1.3%之间 ,相对标准偏差 RSD≤ 3.6 % ,检出限在 0 .2— 5 1.0μg/ L之间 ,方法快速简便 ,结果准确。比较了微波消解和干灰化法溶样的测定结果     

Fluctuations in number of photons in region of unstable behavior in process of intracavity generation of second harmonic

Quantum fluctuations of the number of photons of the fundamental mode and of the second harmonic in the process of intracavity generation of the second harmonic in the unstable region of the system are studied. The distribution functions of the number of photons of interacting modes are calculated in the positive P-representation. The functions of the joint distribution of the number of photons of the fundamental mode and the number of photons in the second harmonic are also studied.     

皮革中甲醛含量测量不确定度评估

依据GB/T 19941-2005标准,测定了皮革中的甲醛含量,对测量结果的不确定度来源进行了分析和评定,并计算出合成不确定度和有效自由度,最后根据JJF1059规范要求给出了甲醛测量不确定度表达式.     

一种在弱酸性介质中有电化学发光性能的鲁米诺衍生物

报道了一种鲁米诺的衍生物-3-(1-乙酰丙酮偶氮)苯二甲酰肼在酸性介质中的电化学发光行为,该化合物与鲁米诺类似,发生两步电化学氧化反应,但其氧化电位较鲁米诺低约0.5V,在氧化铟锡玻璃电极上具有良好的电化学发光性能,有效地避免了氧化铟锡玻璃电极本身的发光干扰.不仅在碱性介质中具有较高的电化学发光效率,而且在酸性介质中也产生较稳定的电化学发光,在1.0×10-6mol/L以上浓度,电化学发光强度与浓度有良好的线性关系.     

Correlation in calculations of density of states in thin films

The density of electronic states and its spatial distribution in thin films are considered including the electron correlations in the coherent phase approximation applied to the intra-atomic interaction. This new approach allows us to derive the line shape for electronic levels which is important from the point of view of the convergency for the density function in the case of systems with restricted dimensions. Detailed calculations are performed for 4s copper film functions with the fcc lattice and various crystallographic orientations of the surfaces.The authors are very grateful to Professor L. Valenta (Prague) for his kind interest in this paper and to Dr. J. Mizia (Cracow) for helpful discussions. We would like to express our gratitude to Professor M. Wonicki and Mrs M. Firszt (Toru) for their help in obtaining the computer program procedure for two-particle interaction integrals calculations.The paper has been done in the framework of the Problem M.R I-11.     

Inhibition of corrosion of aluminium in presence of fluorescein in basic medium

The influence of Fluorescein in conjunction with calcium oxide on the corrosion of Aluminium in 1.0 N NaOH was studied by galvanostatic studies and weight loss studies. It has been found that the inhibition of corrosion of aluminium increased with the increasing concentration of the inhibitor. The maximum inhibition efficiency of fluorescein alone was found to be 30.80%. However, the addition of calcium oxide increased the maximum inhibition efficiency to 53.71%. The corrosion process was found to be under the anodic control, in the presence or in the absence of inhibitor. The inhibition was found to be mixed type. Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, Inida, Nov. 28–30, 2003.     

Deflection of IR-radiation in n-InSb in the presence of temperature-electrical instability in a magnetic field

The formation of an S-shaped volt-ampere characteristic (VAC) during the heating of a specimen of n-type indium antimonide by a dc electric current in the presence of an external magnetic field is considered. In the calculation of the VAC the temperature dependences of the band gap width, the carrier density, the mobility, and the heat conductivity are taken into account. The angle of deflection of IR-radiation in indium antimonide is calculated using the density distribution over the cross section of the specimen derived from the integration of heat conductivity equation. The experimental and theoretical dependences of the deflection angle on the current are in agreement in order of magnitude and indicate that it is possible to use the temperature instability for the construction of laser radiation deflectors in the IR range.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 35–40, November, 1984.The authors are grateful to V. L. Bonch-Bruevich and I. P. Zvyagin for useful discussion and valuable critical remarks.     

Emergence of differences in potential in wood as a result of natural changes in temperature

The emergence of differences in potential in a natural macromolecular heterogeneous structure (wood) upon natural changes in temperature with allowance for humidity is considered. It is shown that the magnitude of the emerging difference in potential in the wood is proportional to the change in temperature and grows along with the humidity of the wood.     

Formation of Dislocations in the Process of Impurity Diffusion in GaAs

Russian Physics Journal - A study of the formation of dislocations in the process of impurity diffusion in GaAs has been carried out. The formation of dislocations in GaAs diffusion layers doped...