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951.
傅里叶变换红外光谱仪探测器仪器响应函数研究   总被引:2,自引:0,他引:2  
由于傅里叶变换红外光谱仪探测器在各个波段的仪器响应不相同,在应用过程中无论是利用光谱的绝对强度还是相对强度,都需要应用标准黑体对仪器进行定标,找出仪器响应函数。该文对加拿大BOMAN公司MR154型傅里叶变换红外光谱议配带的两个红外探测器(锑化铟InSb、碲镉汞MCT)的仪器响应函数进行了研究,并找出了它们随黑体温度(辐射亮度)的变化规律。该规律对傅里叶变换红外光谱仪的定标和保证所测辐射谱的正确性有重要意义。  相似文献   
952.
Abstract According to the regulation of growing and decay of artificial radioactive nuclide, a formula used to subtract the effect of characteristic γ-ray of the others to that of measured reaction was deduced. And then the cross sections of 120Te (n, 2n)119mTe reaction induced by neutrons around 14 MeV were measured by activation relative to the 93Nb (n, 2n)92mNb. In the process of the cross sections measured to be calculated, it was subtracted that the effect of characteristic γ-ray of 126Te (n, p)126Sb to that of measured 120Te (n, 2n)119mTe reaction using the formula deduced. The experimental results were (689±37) and (750±41) mb at the neutron energies of (13.5±0.3) and (14.6±0.3) MeV, respectively. Measurements were carried out by γ-detection using a coaxial HPGe detector. As samples, spectroscopically pure tellurium powder has been used. The fast neutrons were produced by the T(d, n)4He reaction. The neutron energies in these measurements were determined by the method of cross-section ratios between 90Zr (n, 2n) 89m+gZr and 93Nb (n, 2n) 92mNb reactions.  相似文献   
953.
宏观尺寸弯曲石英管对中低能电子束的导向作用   总被引:1,自引:0,他引:1  
研究了宏观尺寸的弯曲圆柱形石英管对 1 100, 1 300和1 500 eV 3种能量电子束的导向作用, 并对实验结果与相同材质和尺寸的直管的情形进行了分析对比。 实验中利用一个位置灵敏法拉第筒对从石英管出射的电子束进行探测, 获得从管道中出射的电子束流强度在位置灵敏法拉第筒各道上的分布, 其结果显示宏观尺寸石英管对电子束存在导向作用。 与慢速高电荷态离子和绝缘毛细管相互作用的物理过程类似, 这种导向效应是由电荷在管壁内表面自组织充电引起的。 实验还发现, 入射电子束流的强度越强, 其导向作用越明显, 这与微观尺寸毛细管对慢速高电荷态离子的导向作用不同。 石英管导向能力与管的尺寸、 形状及材料之间的关系还有待进一步的系统研究。 It was inevstigated in the experiment that the guiding effect of electron beam with energy of 1 100, 1 300 and 1 500 eV through a bended cylindrical quartz tube with macro sized. A position sensitive Faraday cup was developed and used to detect the electron beam transmitted through the quartz tube, and the distribution of transmitted beam current on each channel of the Faraday cup was acquired. Results indicate the existence of guiding effect which is due to the self organized charge up in the inner wall of the quartz tube similar to that of the highly charged ions. We also found that the guiding ability of the tube is related to the incident beam intensity. The relationship between the guiding ability and the material as well as the size of the tube is to be studied in the near future.  相似文献   
954.
We present the DKP oscillator model of spins 0 and 1, in a noncommutative space. In the case of spin 0, the equation is reduced to Klein-Gordon oscillator type, the wave functions are then deduced and compared with the DKP spinless particle subjected to the interaction of a constant magnetic field. For the case of spin 1, the problem is equivalent with the behavior of the DKP equation of spin 1 in a commutative space describing the movement of a vectorial boson subjected to the action of a constant magnetic field with additional correction which depends on the noncommutativity parameter.  相似文献   
955.
From the linear Vlasov equation,the theoretical investigation on relativistic backward wave osciUator is performed.The relationship between the microwave power and the guiding magnetic field,which accords with the results of the particle simulation and experiments,is deduced.  相似文献   
956.
针对异径管的冲蚀失效问题,以管壁腐蚀产物保护膜为研究对象,主要研究流固耦合对管道 冲蚀破坏的作用机理. 建立流固耦合数理模型,推导出在任意拉格朗日-欧拉(Arbitrary Lagrange-Euler, ALE)描述下的黏性流体N-S方程和腐蚀产物保护膜固体区域的控制方程, 分析管壁边界层多相流介质流动与腐蚀产物保护膜破损之间的耦合作用. 以异径管冲蚀失效 为例,运用多物理场耦合软件,分析了异径管流体流向、结构和规格对保护膜变形的影响, 模拟结果表明:流向为``大进小出'的冲蚀较严重;偏心异径管比同心异径管冲蚀严重;两 端管径差越大,冲蚀越严重. 可为异径管的失效分析、优化设计和在役检验提供参考.  相似文献   
957.
利用GEANT4和Garfield气体探测器模拟程序模拟了Micromegas中子探测器位置特性。 在漂移极上加一层聚乙烯薄膜作为转换材料, 通过反冲质子法测量中子的位置。 提出了一套通过设定探测器上层结构的方案来得到探测器的位置分辨特性。 通过对模拟结果的分析与比较, 得到一种易于测定探测器位置分辨特性的方法。 该工作不仅可以优化气体探测器结构设计, 缩短实验周期, 而且还能极大程度地节约经费。 In the present work, the spatial resolution of Micromegas as a neutron detector was simulated with GEANT4 and Garfield program. The polyethylene foil was used as neutron converter. A new method based on structural setting on the top layer of the detector was adopted to obtain spatial resolution. According to our simulation, it turned out to be a better spatial resolution, and this method was easily realized in experiment.  相似文献   
958.
包伯成  刘中  许建平 《中国物理 B》2010,19(3):30510-030510
This paper presents a new smooth memristor oscillator, which is derived from Chua's oscillator by replacing Chua's diode with a flux-controlled memristor and a negative conductance. Novel parameters and initial conditions are dependent upon dynamical behaviours such as transient chaos and stable chaos with an intermittence period and are found in the smooth memristor oscillator. By using dynamical analysis approaches including time series, phase portraits and bifurcation diagrams, the dynamical behaviours of the proposed memristor oscillator are effectively investigated in this paper.  相似文献   
959.
QCM-D研究蛋白质与多糖的相互作用   总被引:1,自引:0,他引:1  
林园  黄庆荣  苏朝晖 《应用化学》2010,27(5):505-509
应用具有耗散因子功能的石英晶体微天平(QCM-D)检测了多糖多层膜的构筑过程以及蛋白质在多层膜上的吸附行为。 研究结果表明,通过层层组装的方法,可以实现多糖卡拉胶多层膜的构筑,并且随着卡拉胶电荷密度的增加,其组装量减少。 研究了牛体血清蛋白(BSA)在卡拉胶上的吸附行为。 结果发现,BSA的吸附行为强烈地依赖于卡拉胶的电荷密度和基体的粗糙度。 通过QCM-D实时监测了BSA在卡拉胶上的动力学吸附曲线,同时根据ΔD值推测了BSA在不同的基底表面上所形成的结构及吸附行为。  相似文献   
960.
A perturbation theory model that describes splitting of the spectra in highly symmetrical molecular species in electrostatic field is proposed. An anahrmonic model of a two-dimensional oscillator having Kratzer potential energy functionis used to model the molecular species and to represent the unperturbed system. A selection rule for the radial quantum number of the oscillator is derived. The eigenfunctions of a two-dimensional anharmonic oscillator in cylindrical coordinates are used for the matrix elements representing the probability for energy transitions in dipole approximation to be calculated. Several forms of perturbation operators are proposed to model the interactionbetween the polyatomic molecular species and an electrostatic field. It is found that the degeneracy is removed in the presence of the electric field and spectral splitting occurs. Anharmonic approximation for the unperturbed system is more accurate and reliable representation of a real polyatomic molecular species.  相似文献   
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