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利用SHML模型计算了密度为ρ=1g·cm-3、温度为150eV、200eV、250eV、300eV、400eV的Sn等离子体的随光子能量变化的辐射不透明度及Rosseland平均不透明度.分析了不透明度随光子能量变化曲线的吸收峰值(不透明度峰值)与能级跃迁的对应关系.还将Sn的Rosseland平均不透明度与DCA/UTA及STA模型计算结果作了比较,吻合较好.     

蒙药心舒安中锗的差分脉冲极谱研究

在pH=1.30的H2SO4和3,4-二羟基苯甲醛(DHB)底液中,采用差分脉冲极谱法,测得无机锗的脉冲极谱波.其峰电位为Ep=-0.53V.Ge(Ⅳ)浓度在1.03×10-3-1.04×10-4mol·L-1范围内与峰电流呈线性关系,样品中总锗和无机锗的回收率分别是95.72%和96.43%.     

土壤的光谱特征及氮含量的预测研究

应用近红外光谱分析技术(NIR)测定土壤参数具有快速、方便的特点.文章分析了不同含水率、不同颗粒大小的土壤样本在不同测试角、不同测试高度对土壤光谱的影响,并得到了不同含水率和不同粒径土壤的含氮量预测模型.研究了这些因素对含氮率测量的影响,分析了NIR技术在田间实地应用预测的可能性.研究表明,光谱仪在距土壤高度为100 mm,测试角为45°时,具有最大的吸光度.土壤粒径和含水率这2个参数明显影响,当粒径在0.5～5 mm变化时,含氮量预测相关系数r为0.81左右,当土壤粒径在＜0.25和＞5 mm模型的预测能力变差.当土壤样品呈天然潮湿状态时,氮的预测结果较差.而样品干燥以后,预测相关系数较高.为土壤原位光谱测试提供了依据.     

Structural Stability of CaCuMn6O12 under High Pressure and Low Temperature

In situ high pressure energy-dispersive x-ray synchrotron radiation diffraction and resistance experiments are carried out on CaCuMn6O12. Its crystal structure is stable in the measured pressure range. The equation of state of CaCuMn6O12 is obtained from the V/Vo - P relationship （V and Vo are the volumes at pressure P and at atmosphere）. The bulk modulus Bo is calculated based on the Birch-Murnaghan equation. Low temperature x-ray diffraction shows no phase transition occurring down to 160K.     

Structural Change in Au^3＋-Doped BK7 Glass Irradiated by Femtosecond Laser

We report on structural change in an Au^3＋-doped BK7 glass irradiated by an infrared femtosecond laser at 800 nm. A grating structure is inscribed in the glass sample. The glass sample is then annealed at various temperatures. Structural change of the grating is observed by an optical microscope. Absorption spectra indicate that colour centres are induced after the laser irradiation, and they decrease with increasing annealing temperature. Au nanoparticles are precipitated at high temperatures （≥ 600℃）. The mechanisms of the phenomena are discussed.     

共沸蒸馏GC/MS测定非卤代挥发性有机物的方法研究

讨论了用共沸蒸馏法浓缩处理水、土壤、固废样品或其萃取液中不易吹除、具挥发性、且易溶于水的非卤代挥发性有机物,并用气相色谱质谱联用仪定性定量的方法.     

Retention Behaviors of Uronic Acid-containing Polysaccharides and Neutral Polysaccharides in HPGPC

The determination of molecular weights (Mw) of polysaccharides has served as an important process since the physical properties of the polysaccharides are closely related to their Mw and/or molecular weights distribution (MWD). For Mw and MWD determinations, high performance gel permeation chromatography (HPGPC) has gained wide acceptance as a preferred method due to its high sensitivity, speed and reproducibility. In chromatography, it is well known that the molecular weights are determ…     

硅衬底阳极氧化铝膜的荧光发射研究

报道了用电子束蒸发技术在硅守底上沉积，并于１５ｗｔ％Ｈ２ＳＯ４，温度２５℃和４０Ｖ直流电压条件下阳极氧化铝薄的制备（膜厚约４００ｎｍ）。研究了该阳极氧化铝膜的红外吸收光谱（ＦＴＩＲ）、光致荧光光谱（ＰＬ）和荧光激发光谱（ＰＬＥ）。发现其荧光光谱在２８０￣５００ｎｍ范围内由三个主发射带组成，其峰值分别位于３１２ｎｍ，３６７ｎｍ和４４９ｎｍ。所有这三个ＰＬ带，经分析都与阳极氧化铝膜中的氧化铝膜中的氧空     

有向图n·■_m的优美性

给定有向图D(V,E),如果存在一个单射f:V(D)→{0,1,…,|E|}使得对于每条有向边(u,v),诱导函数f′:E(D)→{1,2,…,|E|}是一个双射函数,其中,f′(u,v)=[f(v)-f(u)](mod(|E|+1)),则f称为有向图D(V,E)的优美标号,f′称为有向图D(V,E)的诱导的边的优美标号.本文讨论了有向图n.■m的优美性,并且证明了当m=23且n为偶数时,n.■m是优美有向图.