ICP发射光谱测定保偏光纤应力棒中的三氧化二硼

本文提出了用ＩＣＰ发射光谱仪测定保偏光纤应力棒中的三氧化二硼的方法，将应力棒粉碎后，使用ＨＦ在压力溶样中消解，最后溶液的介质为０．５％氢氟酸，并采用耐腐蚀的样品引进系统进行ＩＣＰ光谱测定。分析程序简单，准确度高，该方法回收率为９９－１０１％，相对标准偏差为１．０４％。     

ICP－AES法同时测定柠檬酸中铁、铜、钙、铅

本文介绍了ＩＣＰ－ＡＥＳ法同时测定柠檬酸中铁、铜、钙、铅的方法。试样以干法分解，盐酸溶解残渣后进行测定。回收率为９０．２％－１０５．８％，ＲＳＤ＜２．６６％。     

ICP－AES法同时测定聚酯切片中的钛和铁

本文介绍ＩＣＰ－ＡＥＳ法同时测定聚酯切片中钛和铁的方法。试样以干法分解，以硫酸，硫酸铵溶解残渣后进行测试。回收率为９３．５％－１００．６％，ＲＳＤ＜３．８３％     

ICP－AES法同时测定磷铁中的主含量元素和杂质

本文研究用ＩＣＰ－ＡＥＳ法同时测定磷铁的主含量元素Ｐ和杂质元素Ｓｉ、Ｍｎ、Ｔｉ、Ｖ、Ｃｒ的方法。采用碱熔酸化分解试样，选Ｂ为测Ｐ的内标元素，回收率为９６％－１０２％，最大相对标准偏差为８．６０％，大多数结果的相对标准偏差小于５％。     

动物脑组织中微量钙的ICP—AES法测定

本文利用ＩＣＰ－ＡＥＳ法测定了大白鼠脑组织中的微量钙，并对经典的Ｃａ－ＰＯ４干扰体系在ＩＣＰ－ＡＥＳ中的影响进行了实验，结果表明，样品消解后可直接进样，磷不影响钙的测定，方法的ＲＳＤ为１．１６％，样品加标回收率为９７％，优化实验条件下，对降低干扰，提高分析结果的准确度是至关重要的。     

彩色电视荧光级氧化钇中稀土杂质的ICP—AES测定

本文采用国产ＷＰ－２Ｌ型平面光栅摄谱仪配置国产ＧＰ３．５Ｄ型ＩＣＰ光源进行了彩色电视荧光级氧化钇中１４个稀土杂质元素分析方法的研究。样品溶液以不去溶方式引入ＩＣＰ。当样品溶液中Ｙ２Ｏ３的浓度为２０ｍｇ／ｍｌ时，测定了限分别为铕，镱和镥０．０００２０％，镧，铈，钕，钆，镝，钬，铒和铥０．０００５０％，镨，钐和铽０．００１０％。相对标准偏差为３．２－９．８％。     

彩色电视荧光级氧化钇中稀土杂质的ICP－AES测定

本文采用国产ＷＰ－２Ｌ型平面光栅摄谱仪配置国产ＧＰ３．５Ｄ型ＩＣＰ光源进行了彩色电视荧光级氧化钇中１４个稀土杂质元素分析方法的研究。样品溶液以不去溶方式引入ＩＣＰ。当样品溶液中Ｙ２Ｏ３的浓度为２０ｍｇ／ｍｌ时，测定下限分别为铕、镱和０．０００２０％，镧、铈、钛、钆、镝、钬、铒和铥０．０００５０％，镨、钐和铽０．００１０％。相对标准偏差为３．２～９．８％。     

ICP—AES法测定复合肥中磷,钾,锌,锰和硼

用ＩＣＰ－ＡＥＳ法同时测定了复合肥中磷，钾锌锰和硼，确定了仪器的工作参数，对分析线的选择，背景扣除。酸度影响和共存元素间的干扰等进行了研究。方法的回收率为９５％－１０４％，相对标准偏差为２．６６％－５．５４％。     

ICP-AES法测定锡锭中微量镉的方法研究

本文研究了用电感耦合等离子体光谱法ＩＣＰ－ＡＥＳ测定锡锭中微量镉的分析方法，考察了基体元素的影响，方法简便、快速、准确，合成样品的回收率为９８％—１０５％，相对标准偏小于２％，检出限为０．００１９μｇ／ｍＬ。     

P—矩阵法测定安钠咖注射液中两组分的含量

本文采用Ｐ－矩阵法不经分离同时测定安钠咖注射液中咖啡因和苯甲酸钠的含量。计算程序用ＢＡＳＩＣ语言编制。咖啡因和苯甲酸钠的平均回收率分别为１００．０和９９．９５％，变异系数分别为０．４０％和０．６５％，方法简便，快速，样品测定结果与药典法测得结果基本一致。     

基于光干涉法的光学玻璃应力测量方法研究

以平板理论为基础,利用牛顿环应力变形导致干涉图样的微小变化,提出一种基于光干涉法测量玻璃体应力的无损测量方法。理论推导出牛顿环曲率半径与应力之间的变换关系,利用自行设计的可安装在牛顿环仪上的施压装置,实验研究了施加应力与干涉图样的变换关系,通过理论分析与实验比较,证明了用牛顿环干涉法测量应力的可行性。利用该装置及方法对光学玻璃试样的应力进行测量,测量结果与实际施加的应力进行比较,误差最小为0.8%。     

First-principles studies of HF molecule adsorption on intrinsic graphene and Al-doped graphene

In the search for a high-sensitivity sensor for HF gas, the adsorption of HF molecules on both intrinsic and Al-doped graphene sheets is studied by first-principles calculations. We find that the adsorption mechanisms of HF molecules are different for intrinsic graphene and Al-doped graphene. Al-doped graphene has higher adsorption energy and shorter connecting distance to the HF molecule than intrinsic graphene. The calculated net electron transfers, electronic density difference images and densities of states give evidence that the adsorption of HF molecules on Al-doped graphene is by chemisorption, while there is weak physisorption on intrinsic graphene. Therefore, Al-doped graphene can be expected to have applications as a novel sensor for the detection of HF gas. The HF molecules adsorbed on Al-doped graphene material can be reactivated by applying an external electric field of 0.013 a.u.     

LJ流体非牛顿现象的分子动力学模拟

使用非平衡分子动力学模拟方法研究了单原子LJ流体的非牛顿流变行为,并在系统中分别施加稳态Couette流场和振荡剪切流场.在Couette流场的模拟中,流体出现剪切变稀和法向应力差效应,不同剪切率下的径向分布函数反映了流体分子由于剪切所导致的微观结构变化,通过分析势能函数发现当剪切率增大时,分子间排斥作用增强,吸引作用减弱.在振荡剪切流场的模拟中,发现剪切应力和剪切率之间的相位差随频率增加而增加,随频率增加复数粘度的实部先增大再减小,虚部单调增加,导致虚部粘度相对实部粘度比例增大,弹性模量和粘性模量之比也随频率增加而增加.这三点现象表明LJ流体出现粘弹性行为,且在高频率下,弹性所占比重增大.     

熔石英表面杂质元素在酸蚀过程中的变化

为了探寻熔石英表面痕量杂质元素种类以及随HF酸蚀刻过程中的变化情况,用质量分数为1%HF酸溶液对熔石英进行长达24,48,72,96 h的静态蚀刻实验。结合飞行时间二次离子质谱（TOF-SIMS）和X射线光电子能谱（XPS）测试分析结果发现,熔石英试片表面的痕量杂质元素主要含有B,F,K,Ca,Na,Al,Zn和Cr元素,其中绝大部分都存在于贝氏层中,在亚表面缺陷层检测到有K,Ca元素。所含有的K,Na杂质元素会与氟硅酸反应生成氟硅酸盐化合物。分析表明,在HF酸蚀刻的过程中一部分杂质元素将被消除,一部分杂质元素和生成氟硅酸盐化合物会随着蚀刻液逐渐从熔石英表面向表面纵深方向扩散并被试片吸附沉积,且随着深度的加深各元素的相对含量逐渐减少。     

Investigation of Brillouin effects in small-core holey optical fiber: lasing and scattering

We demonstrate for what is believed to be the first time a Brillouin laser based on a holey fiber (HF). Using a simple Fabry-Perot resonator scheme containing a 73.5-m-long highly nonlinear HF with an effective area of 2.85 microm(2) , we obtain a threshold of 125 mW and a slope efficiency of ~70% . Stimulated and spontaneous Brillouin scattering effects are investigated in the HF, and we show that the high lasing threshold is due mainly to reduction of the effective gain coefficient caused by structural nonuniformity along the fiber length.     

Relativistic warm plasma waveguide under the effects of plasma electrons and HF electrical field on Buneman instability

The stabilization effect of a strong HF (pump) electrical field and plasma electrons on a two-stream (Buneman) instability in a plane relativistic warm plasma waveguide is investigated; using the separation method to solve the two-fluid plasma model we separate the problem into two parts. The “temporal” (dynamical) part enables us to determine the frequencies and growth rates of unstable waves; this part within the redefinition of natural frequencies coincides with the system describing HF suppression of Buneman instability in uniform unbounded plasma. Natural frequencies of oscillations and spatial distribution of the amplitude of the self-consistent electrical field are determined from the solution of a boundary-value problem (“space part”) taking into account specific spatial distribution of plasma density. Plasma electrons are considered to have a relativistic thermal velocity. It is shown that the growth rate of instability in relativistic warm plasma is reduced compared to non-relativistic (cold or warm) plasma and relativistic cold plasma. In addition, it is found that the plasma electrons have no effect on the solution of the space part of the problem.     

HF spectrum activity prediction model based on HMM for cognitive radio applications

Although most of the research on Cognitive Radio is focused on communication bands above the HF upper limit (30 MHz), Cognitive Radio principles can also be applied to HF communications to make use of the extremely scarce spectrum more efficiently. In this work we consider legacy users as primary users since these users transmit without resorting to any smart procedure, and our stations using the HFDVL (HF Data+Voice Link) architecture as secondary users. Our goal is to enhance an efficient use of the HF band by detecting the presence of uncoordinated primary users and avoiding collisions with them while transmitting in different HF channels using our broad-band HF transceiver.A model of the primary user activity dynamics in the HF band is developed in this work to make short-term predictions of the sojourn time of a primary user in the band and avoid collisions. It is based on Hidden Markov Models (HMM) which are a powerful tool for modelling stochastic random processes and are trained with real measurements of the 14 MHz band.By using the proposed HMM based model, the prediction model achieves an average 10.3% prediction error rate with one minute-long channel knowledge but it can be reduced when this knowledge is extended: with the previous 8 min knowledge, an average 5.8% prediction error rate is achieved.These results suggest that the resulting activity model for the HF band could actually be used to predict primary users activity and included in a future HF cognitive radio based station.     

Murrell-Sorbie势能参数与双原子分子光谱数据的关系研究

研究了Murrell-Sorbie势能参数与双原子分子光谱数据的关系.根据光谱数据编程计算了卤化氢分子的力常数和Murrell-Sorbie势能参数.反过来,运用ab initio和非线性最小二乘法拟合出了HF分子的Murrell-Sorbie势能函数和势能参数;并由此计算了HF分子的光谱数据,与实验光谱数据符合较好.这对难以获得实验光谱数据的双原子分子和离子的动力学研究有一定的参考价值.     

Lithium crystal properties from high-quality Hartree-Fock wave functions

Properties derived from lithium b.c.c. crystal Hartree-Fock (HF) calculations, using LCAO-type Bloch functions and including 2s, 2p and 3d Slater-type basis orbitals, are presented. These include total energies, lattice parameters, band gaps, widths of the occupied part of valence band, bulk modulus and Fermi surface geometry. Energetic quantities are in qualitative agreement with our earlier work. Their disagreements with experiment again underscore some inadequacies of HF. The bulk modulus is overestimated by about 50%, which is typical for HF-based molecular force constants. The Fermi surface is calculated to have a maximum distortion (in the 〈110〉 direction) of about 3.5%. This is in agreement with the best experiments. The sensitivity of predicted distortions to Brillouin zone integration points is discussed.