铝合金薄板材的直读光谱分析方法

利用火花直读光谱仪，分析厚度为0.2-0.3mm的铝合金薄板材，分析方法的精密度和准确度令人满意。     

碳素结构钢的光电发射光谱分析方法

本文研究了火花光源－原子发射光谱法测定碳素结构钢化学成分的最佳条件，根据单道扫描型光谱仪自身的特点，选择预然时间和积分时间，并研究了钢坯及轧制成材化学成份的均匀性。将建立的校准曲线应用于进口及国产标样的测定，获得准确结果，将本方法应用于几种实际样品的测定，结果与国家标准方法吻合，对三个含量级样品的精密度实验中，连续重复精密度RSD≤5.24%；继续重复精密度基本上RSD≤5.78%；再现精密度RSD≤7.82%。     

原子吸收光谱仪测量体系的受控分析

通过采用统计质量保证（SQA，Statistical Quality Assurance)技术，对原子吸收光谱仪（AAS）测量体系的性能进行了线性假设的受控分析，研究结果表明，该程序的应用能保证光谱仪测量体系始终处于统计受控状态，确保测试条件下数据结果的有效性，有利于分析测试试验室质量保证活动的开展。     

ZM-Ⅱ型原子吸收分光光度计的研制

由于塞曼效应原子吸收分光光度计可以自动完成背景和光源强度变化的同时校正,使测量结果准确可靠,充分发挥了石墨炉灵敏度高的优点,引起了国内外光谱仪研制工作者的重视,产品频繁更新换代。1980年我们研制成功我国第一台ZM-Ⅰ型塞曼效应原子吸收分光光度计。在过去工作的基础上,我们分析了国内外各种型号原子吸收光谱仪     

用于原子吸收光谱仪的高灵敏度燃烧器

本文介绍了一种用于原子吸收光谱仪的气－样分进、双通道燃烧器，经过实际检测比较，该坷提高原子吸收灵敏度１￣５倍，且稳定性好。     

铋黄铜中微量元素的高重复频率激光剥离-火花诱导击穿光谱定量分析

铋黄铜具有很好的机械加工性能且更为环保,具有广泛的应用.本文采用高重复频率激光剥离-火花诱导击穿光谱技术来实现铋黄铜中微量元素的快速和高灵敏分析.实验采用小型化光纤激光器作为剥离光源,采用小型化光纤光谱仪采集光谱,对铋黄铜中的铋、铅和锡三元素开展了定量分析.实验确定等离子体的温度和电子密度分别为7962±300 K和1.049×10~(–17) cm~(–3).在该条件下建立了铋、铅和锡三元素的校正曲线,并得到了较好的拟合优度.现有条件下三元素的检测限分别达到了25.5×10~(–6),64.2×10~(–6)和316.5×10~(–6).其中锡的检出限较高,与锡的原子谱线强度较弱有关.结果表明,采用小型化的高重复频率激光剥离-火花诱导击穿光谱仪可以实现对铋黄铜中微量元素的便捷和高灵敏分析.     

氩气自动控制器在DV4光谱仪上的应用

介绍了氩气自动控制器的制作、工作原理及在光谱仪上的应用.该控制器结构简单,组装调试容易,性能稳定而且成本很低,在DV-4光谱仪上经过长时间的应用,分析结果重现性好,准确度高,适用范围广,可方便安装于火花直读光谱仪上,比不用氩气节能控制器节约80%以上的氩气.效果很好.     

火花光源发射光谱法测定钢中微量铌

研究了火花光源光谱仪测定钢中微量铌的方法 ,确定了制样和分析条件 ,校正了共存元素的干扰。方法简便、快速 ,具有良好的准确度和精密度 ,结果令人满意     

光谱仪器分析在中国药典中的应用

本文阐述了光谱仪器分析方法包括可见紫外光谱法，红外光谱法，原子吸收光谱法和荧光光谱法，在中国药典药品检验中的广泛应用。     

WFX－Ⅱ型原子吸收光谱仪的正确使用与维护

本厂ＷＦＸ－Ⅱ型原子吸收光谱仪，是一台陈旧的老设备，通过改造和正确使用与维护，仍能正常运行，在厂里生产中充分发挥了老设备的作用。本文还简要地介绍了使用原子吸收光谱仪的经验，在国产设备上怎样正确使用Ｎ２Ｏ－Ｃ２Ｈ２火焰，并对于使用Ｎ２Ｏ－Ｃ２Ｈ２火焰所产生不安全因素进行了分析。     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

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.     

Analysis of Laser-generated Rayleigh wave on viscoelastic materials

In order to understand the viscoelasticity of material, this research has been conducted to study the propagation characteristics of viscoelastic Rayleigh wave theoretically. A model is presented for the pulsed laser generation of ultrasound on viscoelastic medium surface. Referred to the Kelvin model, the frequency equation and the normal displacement of viscoelastic Rayleigh wave were derived, the influence of the viscoelastic modulus on dispersion and attenuation was discussed. From the theoretical calculation, it is shown that the effect of viscoelasticity on the attenuation of Rayleigh wave is more than that on its dispersion. In the case of a weak viscosity, the attenuation of viscoelastic Rayleigh wave is directly proportional to viscosity modulus; the effect of shear viscosity on the attenuation is much more than that of bulk viscosity. The transient response of viscoelastic Rayleigh wave was also simulated using Laplace and Hankel inversion transform, which are showed in good agreement with the theoretic predictions. The model provides a useful tool for the determination of viscoelastic parameters of medium.     

Dynamics of a waveguide pulsed-periodic CO2 laser with loss modulation

The nonlinear dynamics of a waveguide CO₂ laser with combined periodic loss and pumping modulation is investigated theoretically and experimentally. The possibilities of controlling time and energy parameters of the output radiation using the corresponding selection of the detuning of the cavity's longitudinal mode from the center of the amplification line, the amplitude, and the frequency of loss modulation are demonstrated. The observed asymmetric dependence of the lasing-radiation density on the detuning of the cavity frequency is explained by the attendant modulation of the refractive index of the loss modulator. To whom correspondence should be addressed. B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 68, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 4, pp. 471–478, July–August, 1999.     

Optical Pulse Compression Schemes That Use Nonlinear Bragg Gratings

Nonlinear optical pulse compression of picosecond pulses typically requires long lengths of optical fiber and multiple components. Periodic structures, such as fiber Bragg gratings, are highly dispersive at wavelengths outside of the photonic bandgap. This implies that such gratings can be used as very short all-fiber compressors. In this paper a number of such compression schemes are reviewed involving uniform and nonuniform fiber Bragg gratings, relying on both soliton and nonsoliton compression principles. Experimental results supporting the corresponding underlying theory are also presented. Finally, an extension of one of the compression schemes is shown, which allows the generation of adjustable high-repetition rate soliton trains.     

Study on the radiation problem caused by electron beam loss in accelerator tubes

The beam dynamic code PARMELA was used to simulate the transportation process of accelerating electrons in S-band SW linacs with different energies of 2.5, 6 and 20 MeV. The results indicated that in the ideal condition, the percentage of electron beam loss was 50% in accelerator tubes. Also we calculated the spectrum, the location and angular distribution of the lost electrons. Calculation performed by Monte Carlo code MCNP demonstrated that the radiation distribution of lost electrons was nearly uniform along the tube axis, the angular distributions of the radiation dose rates of the three tubes were similar, and the highest leaking dose was at the angle of 160° with respect to the axis. The lower the energy of the accelerator, the higher the radiation relative leakage. For the 2.5 MeV accelerator, the maximum dose rate reached 5% of the main dose and the one on the head of the electron gun was 1%, both of which did not meet the eligible protection requirement for accelerators. We adopted different shielding designs for different accelerators. The simulated result showed that the shielded radiation leaking dose rates fulfilled the requirement.     

The effective absorption cross-section of thermal neutrons in a medium containing strongly or weakly absorbing centres

The structure of a heterogeneous system influences diffusion of thermal neutrons. The thermal-neutron absorption in grained media is considered in the paper. A simple theory is presented for a two-component medium treated as grains embedded in the matrix or as a system built of two types of grains (of strongly differing absorption cross-sections). A grain parameter is defined as the ratio of the effective macroscopic absorption cross-section of the heterogeneous medium to the absorption cross-section of the corresponding homogeneous medium (consisting of the same components in the same proportions). The grain parameter depends on the ratio of the absorption cross-sections and contributions of the components and on the size of grains. The theoretical approach has been verified in experiments on prepared dedicated models which have kept required geometrical and physical conditions (silver grains distributed regularly in Plexiglas). The effective absorption cross-sections have been measured and compared with the results of calculations. A very good agreement has been observed. In certain cases the differences between the absorption in the heterogeneous and homogeneous media are very significant. A validity of an extension of the theoretical model on natural, two-component, heterogeneous mixtures has been tested experimentally. Aqueous solutions of boric acid have been used as the strongly absorbing component. Fine- and coarse-grained pure silicon has been used as the second component with well-defined thermal-neutron parameters. Small and large grains of diabase have been used as the second natural component. The theoretical predictions have been confirmed in these experiments.     

Acoustic reflection of rib-stiffened double plates coated with a viscoelastic layer

To predict sound-absorbing performance of anechoic materials,the acoustic reflection problem of a viscoelastic layer backed with periodically rib-stiffened infinite double plates is studied in this paper.The reason why structural theories of plates are not applicable to viscoelastic plates is explained through comparing dispersion and attenuation curves of flexural waves with those of Lamb waves.As a result,（visco-）elastic theory is adopted to deal with（visco-）elastic plates,and ribs are treated by structural theories of plates.The coupling between ribs and plates are solved by Hull＇s method,and solution of the reflected field is obtained.The accuracy of present method is validated by comparing with the results by the structural theories of plates.The influence of a backing on the acoustic reflection of the viscoelatic layer is analyzed by computing reflection coefficients.Performances of different viscoelastic materials are evaluated by the average reflection coefficients.The computational results show that,influence of a backing on the acoustic reflection cannot be suppressed by the viscoelastic materials in low frequencies.The resonance is determined by the coupling of the fluid layer and the double plates.And ribs,which are coupled with the double plates,mainly reduce the acoustic reflection.     

Influence of nonplanar distortions of the tetrapyrrole macroring on the electronic states of porphyrin dications

Quantum-chemical calculations of the excited electronic states of a porphyrin dication have been performed by the CNDO/S method for different angles determining the saddle-like and ruffled distortions of the porphyrin macroring. It is shown that saddle-like distortions arising as a result of a tilt of the pyrrole rings have a significant influence on the energies of the molecular orbitals and energies of the excited electronic states of porphyrin molecules, especially on the oscillator strength of the G→Q transition. The results of the calculations performed are in good agreement with the experimental spectra of porphyrin dications. To whom correspondence should be addressed. Reported at the VIIIth International Conference on Spectroscopy of Porphyrins and Their Analogs, Minsk, September 22–26, 1998. Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 4, pp. 559–562, July–August, 1999.     

Vibrational spectra of the products of interaction of enzymes with a monocarboxylcellulose matrix

By the method of IR spectroscopy it is established that the process of sorption of celiase, trypsin, chymotrypsin, streptase, plasminogen, and plasmin by monocarboxylcellulose (the content of COOH groups is 15 wt.%) is mainly identical. The determining role in the mechanism of binding of monocarboxylcellulose with the considered medicinal enzymes belongs to electrostatic interactions with the formation of ionic bonds between the COO⁻ groups of the matrix and charged amine groups of protein molecules. It is established that the process of interaction of plasmin with oxidized cellulose takes a more active course than with other investigated enzymes. It is shown that the activity of interaction of the enzymes with monocarboxylcellulose can be evaluated by a change in the relative intensity of the band of stretching vibrations of C=O groups. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 6, pp. 771–774, November–December, 1999.     

Influence of microwave radiation on the association processes of rhodamine 6G molecules in aqueous solutions

The influence of the microwave radiation of two frequency ranges (2.0 mm and 6.9 dm) on the absorption spectra of the cationic dye rhodamine 6G has been investigated. A reversible decrease in the quantity of the dimers of the dye molecules after exposure of its aqueous solution to microwave radiation and also the phenomenon of destruction of the associates of the dye molecules under the influence of the microwave field have been revealed. They are discussed from the standpoint of the structural characteristic features of water.__________Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 1, pp. 34–37, January–February, 2005.