毛细管电泳扫描伏安电化学法分离检测肾上腺素、氯丙嗪和异丙嗪

采用自制的高效毛细管电泳扫描伏安电化学检测装置,在磷酸盐缓冲溶液中进行了肾上腺素、异丙嗪和氯丙嗪的分离检测,在优化的条件下获得了较好的检测重现性和低的检出限。结果表明,采用扫描伏安电化学方法不但能够减少电极的污染,而且可以在电泳过程中获得被测物质的伏安特性及检测体系的动态伏安图,更有利于被测物质的识别。     

粉防己碱拮抗α-石英细胞毒性的机理

借助于单细胞阳离子测定系统研究了α-石英诱发细胞毒性过程中,不同外钙浓度时粉防己碱作用后,细胞存活率与胞浆游离钙浓度的变化关系。研究发现粉防己碱可以通过阻断细胞离子通道,拮抗α-石英的细胞毒性。     

A Series Piezoelectric Quartz Crystal Microbial Sensing Technique Used for Biochemical Oxygen Demand Assay in Environmental Monitoring

A new method for biochemical oxygen demand (BOD) determination, which combines the series piezoelectric quartz crystal (SPQC) technique with the growth of a microorganism is presented in this paper. This method needs no immobilization of bacteria and is simple and convenient. When a calibration technique was used for BOD analysis, the detection time was 2.5 h at 37°C. There was a good linear relationship between the frequency shift and BOD value in the range 2.2–11 mg/L and the regression equation was ΔF = 64.10 + 11.23[BOD]. The proposed method was compared with the conventional BOD₅ method. This method was more rapid than the BOD₅ method and the results obtained by the former were in good agreement with those obtained by the latter. The experimental conditions are also discussed in detail.     

Electrochemically induced transformations of heteropolyanions: new electroactive metal oxide films studied by the electrochemical quartz crystal microbalance

New oxide films have been electrodeposited from [P₂Mo₁₈O₆₂]⁶⁻ by potential cycling in mildly acidic aqueous media. To obtain an adherent and persistent film, it is necessary that more than six electrons/molecule be fixed on the framework of the heteropolyanion. The film is then studied in pure supporting electrolyte. In this medium, a remarkable current increase is observed during the potential cycling. Whether the film is deposited on a glassy carbon electrode or on the gold electrode of an electrochemical quartz crystal microbalance (EQCM), exactly the same steady current increase up to a maximum is obtained in cyclic voltammetric measurements. The EQCM reveals a steady mass increase during the continuous cycling of the film in the supporting electrolyte. This behaviour is interpreted as featuring an irreversible water and electrolyte intake into the film, up to a maximum, after which the phenomena observed during reduction and oxidation processes are taken as featuring intercalation/deintercalation, respectively. This behaviour is much the same as described in the literature for WO₃ and MoO₃ bronzes, except that the present films seem very stable and have shown no tendency to dissolve or deactivate. Received: 2 December 1998 / Accepted: 26 January 1999     

Electrochemical quartz crystal microbalance study of ion transport accompanying charging-discharging of poly(pyrrole) films

Electrochemical quartz crystal microbalance studies on poly(pyrrole) electrodes revealed a complex nature of the potential-dependent sorption of ionic substances. It is found that the relative contribution of anions and cations to the overall charge transport process depends upon several factors, such as the oxidation state of the polymer, the composition of the supporting electrolyte as well as on the film thickness. The phenomena observed are discussed in terms of morphological transformations arising as a result of interactions between the polymer and the mobile substances. Received: 21 August 1998 / Accepted: 21 October 1998     

Near-field effect in optics of small objects composed of dipole atoms

A self-consistent problem of interaction of two dipole atoms separated by an unrestricted distance with the field of a quasi-resonance light wave was solved on the assumption that the investigated atoms are Lorentz linear oscillators and the polarizing fields inside the system consist of the Coulomb and the retarded parts. The solution obtained was investigated for the case where the atoms have the same polarizability and the distance between them is much smaller than the length of the external light wave. Formulas for the electric fields inside a small object and outside it have been obtained. It is shown that inside a small two-atom object there can take place longitudinal and transverse optical vibrations accompanied by corresponding dispersion effects depending on the interatomic distance and the angle between the axis of the system and the direction of propagation of the external light wave. The field outside the small object in the wave zone is linearly polarized when the external wave has linear polarization. However, the direction of polarization of the corresponding waves is largely determined by their frequency. It is also shown that the amplitude of the field outside the small object in the wave zone depends greatly on the frequency of the external field and the interatomic distance. The effects observed are considered as a near-field effect in optics of small objects. This phenomena makes it possible to investigate the structure of small objects with the use of optical radiation. Ul'yanovsk Branch of the Institute of Radio Engineering and Electronics, Russian Academy of Sciences, 48 Goncharov Str., Ul'yanovsk, 432700, Russia; e-mail: gadomsky@quant.univ.simbirsk.su. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 6, pp. 765–770, November–December, 1999.     

Electronic structure of C60 films

A complete set of fundamental optical functions of fullerite (C₆₀) films in energy ranges of 2.5–5.0 and 4.0–9.0 eV is calculated using the known spectra of the imaginary and real parts of the dielectric constant. An integrated spectrum of the dielectric constant is decomposed into elementary components. Three basic parameters of each component (the maximum and halfwidth energies and oscillator strength) are determined. Based on the known theoretical calculations of fullerite zones, a scheme of the nature of these components of the dielectric constant is suggested. Udmurt State University, 71, Krasnogeroiskaya Str., Izhevsk, 426034, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 2, pp. 227–232, March–April, 1999.     

Theoretical analysis of self-phase locking in a type II phase-matched optical parametric oscillator

We analyze a doubly-resonant type II phase-matched optical parametric oscillator that includes an intracavity waveplate for inducing mutual injection locking between the signal and the idler. The intracavity waveplate provides a linear coupling between the normally orthogonally polarized signal and idler fields and allows for mode locking at frequency degeneracy. Under mode locked conditions the signal–idler phase difference is locked and the optical parametric oscillator becomes self-phase locked. The signal–idler phase can be adjusted by changing the operating point within the locking range. Two self-phase locked modes with different thresholds and signal–idler phases are possible. Characteristics of the self-phase locked regime are presented for different linear coupling strengths.     

SU(1,1)群的非齐次逆微分实现

利用玻色振子的逆算符构造了SU(1,1)群的生成元和不可约表示的相干态,导出了SU(1,1)群的非齐次逆微分实现.     

非球谐振子势的精确解

严格求解了三维非球谐振,势的Schrodinger方程给出了精确的能谱方程和归一化的径向波函数.获得了径向幂次算符r^s的矩阵元和平均值的计算公式及其递推关系.