用于昆虫外激素研究的微量顶空收集及热解吸气相色谱进样方法初探

描述了一个结合项空气流收集与无溶剂热解吸气相色谱进样的方法。用填充PorapskQ的微量注射器作为吸附管进行气流收集。将收集物不经溶剂洗脱直接进行热解吸进样。用人工合成的昆虫外激素化合物反-7-十二碳单烯乙酸酯（E-7-DA）及顺-5,反-7-十二碳二烯乙酸酯（Z-5,E-7-DDA）测定了方法的回收率,初步探索了运用于昆虫外激素分析的可行性,并讨论了提高回收率的途径。     

退火及铟含量对InGaAs量子点光学特性的影响

 研究了退火条件和In组份对分子束外延生长的InGaAs量子点（分别 以GaAs或AlG aAs为基体）光学特性的影响。表明：量子点中In含量的增加将导致载流子的定域能增加和基态与激发态之间的能量间隔增大。采用垂直耦合的量子点及宽能带的AlGaAs基体可增 强材料的热稳定性。以AlGaAs为基体的InGaAs量子点,高温后退火工艺 (T= 830℃)可改善低温生长的AlGaAs层的质量,从而改善量子点激光器材料的质量。     

后退火对InxGa1xAs 单层量子点光学性质的影响

 研究了以GaAs和Al_0.15Ga_0.85As为基体, 当铟的摩尔分数（x）不同时, 后退火对InxGa1-xAs 单层量子点光致荧光（PL）谱特性的影响。后退火将导致铟含量不同的样品（x=0.23, 0.37, 0.50, 1.0）的PL谱线宽度变窄和蓝移。对于GaAs 基体, 在700℃退火90分钟所造成的PL谱蓝移与退火30分钟相似;(仅当x=0.23时, 退火90分钟所造成的PL谱蓝移小于30分钟)。对于Al0.15Ga0.85As基体, 在700℃退 火30分钟和90分钟, 其PL谱蓝移是不同的。     

Fringe Locking in a Laser Diode Interferometer by Optical Feedback During Modulation of Injection Current

A fringe locking phenomenon in a two beam interferometer using a semiconductor laser subject to optical feedback was, whose injection current is modulated. When a path difference of the interferometer is sufficient, fringes taken by a charge coupled device camera are seen to be stationary and the rms fluctuations of fringe phase is reduced to as low as 0.2ϖ radians from more than 8ϖ radians without the optical feedback. The rms phase fluctuation is independent of frequency and amplitude of the current modulation. The fringe locking has also been observed in the presence of both injection current modulation and piezoelectric transducer mirror vibration.     

Fringe Locking in a Laser Diode Interferometer under Both Mirror Vibration and Injection Current Modulation

We have found that the fringes in a laser diode interferometer can be locked even in the presence of mirror vibration and injection current modulation. A theoretical analysis explains the fringe locking phenomenon. The dependence of wavelength change on both PZT (piezoelectric transducer) mirror vibration and the injection current variation are calculated using a model of coupled resonators consisting of the laser cavity and the interferometer. The fringe phase change caused by the vibration and modulation of the current is derived from this model, and was proven to be suppressed within much less than 2ϖ in excess of an integer multiple of 2ϖ.     

Falling ball viscosimetry of giant vesicle membranes: Finite-size effects

We study the general problem of the friction felt by a spherical solid particle which moves parallel to the membrane of a spherical vesicle. Experiments are carried out with SOPC vesicles at room temperature, with different particle and vesicle sizes. Experimental data show considerable finite-size effects whenever the particle is not very small compared to the vesicle. These effects are found consistent with the hydrodynamical theory of the vesicle-particle problem. This agreement allows for a “robust” determination of membrane viscosity, independently of particle and vesicle sizes. Received 4 January 1999 and Received in final form 11 May 1999     

Flow Injection Chemiluminescence Determination of Isoniazid Using On-Line Electrogenerated Manganese(III) as Oxidant

A novel flow injection chemiluminescence (CL) system for the determination of isoniazid has been proposed. It is based on the direct CL reaction of isoniazid and Mn(III) in sulfuric acid medium. The unstable Mn(III) was on-line electrogenerated by constant current electrolysis. The CL emission intensity was linear with isoniazid concentration in the range 0.1–10 μg/mL; the detection limit was 3.2 × 10⁻² μg/mL. The whole process could be completed in 1 min with a relative standard deviation of less than 5%. The proposed method is suitable for automatic and continuous analysis and has been applied successfully to the analysis of isoniazid in pharmaceutical preparation.     

鲁米诺-高碘酸钾-抗坏血酸体系化学发光反应的研究与应用

基于抗坏血酸在碱性条件下与高磺酸钾和鲁米诺反应产有强的化学发光,建立了流动注射化学发光测定抗坏血酸的新方法。在碱性条件下的氧化过程易产生过氧化物和超氧自由基,是产生化学发光的关键。该法校准曲线线性范围为６．０×１０＾－６－４．０×１０＾－２ｇ／Ｌ,检出限达８×１０＾－７ｇ／Ｌ,相对标准偏差小于４％,采样频率为１２０次／ｈ。     

正交试验在流动注射—氢化物—石墨炉原子吸收分光光度法中的应用

在生产和学科研究中经常需要做许多多因素的试验。如何安排多因素的实验是一个很值得研究的问题。若试验安排得好,则既可减少试验次数,避免试验的盲目性,又可得到好的效果;若试验安排得不好,则试验次数多,还不一定好。正交实验法(又称正交设计或正交法)是研究与处理多因素...     

在线阴离子富集-石墨炉原子吸收光谱法的研究

将流动注射在线预富集系统与石墨炉原子吸收光谱法联用,以强碱型阴离子交换纤维为柱填充材料,以浓盐酸为络合剂,以稀盐酸为洗脱液,用固定洗脱液体积方式测定了Cd,Pb和Zn,富集倍数分别为19,17和15(与直接引入40μL进样量相比),检出限(3σ,ng/L)分别为1.1,8.2和2.6.