5FW软件X光胶片响应在同步辐射源上的实验标定

介绍了５ＦＷ软Ｘ光胶片在同步辐射源上进行响应标定的一种实验是到了５ＦＷ软Ｘ光胶片对波长为１．４７ｎｍ和４．５９ｎｍ软Ｘ光的相对响应实验曲线，并与用理论模型计算的结果进行了比较。     

上海软X光胶片响应的相对标定

介绍了在同步辐射源上用透射光栅对“上海”软Ｘ光胶片进行相对标定的方法，初步研究了“上海”胶片的特性，得到了在２７６ｅＶ和９３０ｅＶ两能点的胶片黑密度与相对曝光量的关系曲线；应用标定结果。     

利用金刚石探测器测量软X光辐射功率

使用天然Ⅱａ型金刚石光电导探测器（ＰＣＤ），测量激光等离子体发射的软Ｘ光辐射。由于探测器在２００ｅＶ～２２００ｅＶ之间具有平响应特性，可以不加滤片直接测量Ｘ光功率和能量。金刚石ＰＣＤ与软Ｘ光能谱仪和平响应Ｘ光二级管的测量结果基本一致。     

X射线胶片的脉冲光源响应标定

用ＬＦ－１１激光装置的１．０６μｍ脉冲激光加热Ｃｕ靶产生的Ｌ－壳层线辐射作脉冲Ｘ射线源，在曝光量为（０．０１～１０）－７Ｊ·ｃｍ－２范围内，标定了ＫＯＤＡＫＡＡ－５，ＫＯＤＡＫＳＷＲ和ＵＦＳＨ－Ｏ软Ｘ射线胶片的响应曲线，并与用连续光源标定的进行了对比．结果表明，这三种ｘ射线胶片，在强脉冲光源曝光条件下，都存在着胶片响应互易律失效问题，过去用连续光源标定的响应曲线，在激光等离子体诊断实验中，已经不能采用．     

用网格衰减膜相对标定SIOFM—5FW软X光底片

点降焦激光等离子体发出的Ｘ射线经晶体色散形成均匀的单色Ｘ射线源，在此基础上，用单层网格作为衰减膜，得到未经衰减和经过衰减的Ｘ射线谱，对无保护膜的ＳＩＯＦ－Ｍ５ＦＷ软Ｘ光底片作了试验性的相对标定，得到了０．９１ｎｍ波长的特性曲线。     

用网格衰减膜相对标定SIOFM─5FW软X光底片

点聚焦激光等离子体发出的Ｘ射线经晶体色散形成均匀的单色Ｘ射线源，在此基础上，用单层网格作为衰减膜，得到未经衰减和经过衰减的Ｘ射线谱，对无保护膜ＳＩＯＦＭ５ＦＷ软Ｘ光底片作了试验性的相对标定，得到了０．９１ｎｍ波长的特性曲线     

X光CCD响应特性

在北京同步辐射源上建立了Ｘ光ＣＣＤ量子效率实验标定方法,获得了１５０ｅＶ～１５００ｅＶ能区范围多个Ｘ光能点的量子效率实验结果,发展了Ｘ光ＣＣＤ量子效率简化计算模型,并对Ｘ光ＣＣＤ表面油沾污对量子效率的影响进行了实验研究和修正。     

用平场光栅谱仪现场标定5FW X光底片

采用像散模式的平场光栅谱仪作为分光元件，点状镁激光等离子体Ｘ射线源为原始光源，获得均匀线性单色较Ｘ射线再生源，在此基础上，用多阶梯衰减膜为相对曝光强度标尺，现场标定了上海感光胶片厂生产的５ＦＷ无保护膜Ｘ光底片，给出了５．０ｎｍ～８．０ｎｍ间的底片响应特性。     

双盘靶等离子体运动和X光辐射

通过双盘靶实验我们观察到了等离子体的运动，运动速度小于３．５×１０７ｃｍ／ｓ；同时观测到了等离子体的会聚发射，Ｘ光的波段约在４００～７００ｅＶ之间，峰值能量在５００～６００ｅＶ之间。     

UFsh—O软X光胶片在质子荧光源上的绝对刻度

介绍在Ｋ—４００质子加速器上，以质子激发低Ｚ材料产生的内壳层荧光（波长０．５０～６．８ｕｍ）作为光源绝对刻度ＵＦｓｈ—Ｏ软Ｘ光胶片．给出了该种胶片的三维黑密度曲线并对结果作了讨论．     

Spectroscopic ellipsometric study of the optical properties of Ag2O film prepared by direct-current magnetron reactive sputtering

The Ag2O film, as-deposited by direct-current magnetron reactive sputtering at a substrate temperature of 150℃, clearly shows a preferential orientation (111), and is capable of lowering the threshold value of the thermal decomposition temperature to about 200℃, which is helpful to its application in optical and magneto-optical storage. This paper fits its optical constants in terms of a general oscillator model by using measured ellipsometric parameters. The fitted oscillator energy 2.487 eV is close to the optical direct interband transition energy value of the Ag2O film determined by Tauc equation; whereas, the fitted oscillator energy 4.249 eV is far from the fitted plasma oscillator energy 4.756 eV by single-oscillator energy. The photoluminescence spectrum centred at about 2.31 eV indicates a direct-energy gap photoluminescence mechanism of the Ag2O film.     

Ellipsometric characterization of PbI2 thin film on glass

The optical properties of polycrystalline lead iodide thin film grown on Corning glass substrate have been investigated by spectroscopic ellipsometry. A structural model is proposed to account for the optical constants of the film and its thickness. The optical properties of the PbI₂ layer were modeled using a modified Cauchy dispersion formula. The optical band gap E_g has been calculated based on the absorption coefficient (α) data above the band edge and from the incident photon energy at the maximum index of refraction. The band gap was also measured directly from the plot of the first derivative of the experimental transmission data with respect to the light wavelength around the transition band edge. The band gap was found to be in the range of 2.385±0.010 eV which agrees with the reported experimental values. Urbach's energy tail was observed in the absorption trend below the band edge and was found to be related to Urbach's energy of 0.08 eV.     

Density of Electronic States in the Conduction Band of Ultrathin Films of Naphthalenedicarboxylic Anhydride and Naphthalenetetracarboxylic Dianhydride on the Surface of Oxidized Silicon

The results of examination of the electronic structure of the conduction band of naphthalenedicarboxylic anhydride (NDCA) films in the process of their deposition on the surface of oxidized silicon are presented. These results were obtained using total current spectroscopy (TCS) in the energy range from 5 to 20 eV above the Fermi level. The energy position of the primary maxima of the density of unoccupied states (DOUS) of an NDCA film was determined based on the experimental TCS data and calculated data and compared with the position of the DOUS maxima of a naphthalenetetracarboxylic dianhydride (NTCDA) film. The theoretical analysis involved calculating the energies and the spatial distribution of orbitals of the molecules under study at the B3LYP/6-31G(d) DFT (density functional theory) level and correcting the obtained energies in accordance with the procedure that was proven effective in earlier studies of the conduction band of films of small conjugated organic molecules. It was found that the DOUS maxima of the NTCDA film in the studied energy interval from 5 to 20 eV above the Fermi level are shifted toward lower electron energies by 1–2 eV relative to the corresponding DOUS maxima of the NDCA film Subdivision of the Ufa Federal Research Centre of the.

     

溅射功率对金属锰膜光学性质的影响

采用磁控溅射方法在Si（111）基片上制备金属锰膜,用椭圆偏振光谱在入射光子能量为2.0–4.0 eV范围内研究了溅射功率对薄膜光学性质的影响. 利用德鲁得-洛伦兹色散模型对椭偏数据进行拟合,结果表明在测量范围内随溅射功率增加薄膜的折射率减小;消光系数随入射光子能量增加先增加后减小,在3.0 eV附近处出现极大值,并且极大值所处的位置随溅射功率增加而向低能方向移动,这主要与溅射沉积的锰薄膜的质量有关,且随溅射功率的增加薄膜的消光系数逐渐趋近于金属锰的数值. 研究结果还表明溅射功率的增加减少了薄膜中的空隙,有利于薄膜的生长. 关键词： 磁控溅射 金属锰膜 椭圆偏振光谱 德鲁得-洛伦兹色散模型     

Nanonails structured ferric oxide thick film as room temperature liquefied petroleum gas (LPG) sensor

In the present work, ferric oxide nanonails were prepared by screen printing method on borosilicate glass substrate and their electrical and LPG sensing properties were investigated. The structural and morphological characterizations of the material were analyzed by means of X-ray diffraction (XRD) and Scanning electron microscopy (SEM). XRD pattern revealed crystalline α-phase and rhombohedral crystal structure. SEM images show nanonails type of morphology throughout the surface. Optical characterization of the film was carried out by UV-visible spectrophotometer. By Tauc plot the estimated value of band gap of film was found 3.85 eV. The LPG sensing properties of the ferric oxide film were investigated at room temperature for different vol.% of LPG. The variations in electrical resistance of the film were measured with the exposure of LPG as a function of time. The maximum values of sensitivity and sensor response factors were found 51 and 50 respectively for 2 vol.% of LPG. The activation energy calculated from Arrhenius plot was found 0.95 eV. The response and recovery time of sensing film were found ∼120 s and 150 s respectively. These experimental results show that nanonails structured ferric oxide is a promising material as LPG sensor.     

Luminescence excitation and its relation to the structures of natural crystalline diamond and diamond-like films

The luminescence excitation spectra (LES) of natural crystalline diamond and amorphous diamond-like films are measured at energies from 4 to 20 eV at the LOCUS station for luminescence and optical studies of the Kurchatov Institute synchrotron radiation source. Two sharp peaks at 5.5 and 10.5 eV are observed in the LES of diamond, while the LES of the film demonstrate only one peak at 10.5 eV. For crystalline diamond, the peaks can be explained within the framework of the diamond band structure and the processes of inelastic scattering of photoexcited holes. Dark-field electron microscope images of the diamond-like film show that, in spite of its amorphous structure, this film contains regions of coherent electron scattering whose dimensions are on the order of 2–5 nm, which is sufficient to describe the film LES using a model for crystalline diamond. The absence of the first peak in the film LES is related to the fact that the absorption coefficient of diamond is very small at 5.5 eV and radiation is only slightly absorbed by the thin film.     

Electron-stimulated desorption of cesium atoms from cesium layers deposited on a germanium-coated tungsten surface

The yield and energy distribution of Cs atoms from cesium layers adsorbed on germanium-coated tungsten were measured, using the time-of-flight technique with a surface-ionization-based detector, as a function of the energy of bombarding electrons, germanium film thickness, the amount of adsorbed cesium, and substrate temperature. The threshold for the appearance of Cs atoms is ～30 eV, which correlates well with the germanium 3d-level ionization energy. As the electron energy increases, the Cs atom yield passes through a broad maximum at ～120 eV. For germanium film thicknesses from 0.5 to 2 monolayers, resonance Cs yield peaks were observed at electron energies of 50 and 80 eV, which can be related to the tungsten 5p and 5s core-level ionization energies. As the cesium coverage increases, the Cs atom yield passes through a flat maximum at monolayer coverage. The energy distribution of Cs atoms follows a bell-shaped curve. With increasing cesium coverage, this curve shifts to higher energies for thin germanium films and to lower energies for thick films. The Cs energy distribution measured at a substrate temperature T = 160 K exhibits two bell-shaped peaks, namely, a narrow peak with a maximum at ～0.35 eV, associated with tungsten core-level excitation, and a broad peak with a maximum at ～0.5 eV, deriving from the excitation of the germanium 3d core level. The results obtained can be described within a model of Auger-stimulated desorption.     

射频磁控反应溅射制备的Ag2O薄膜的椭圆偏振光谱研究

Ag₂O薄膜在新型超高存储密度光盘和磁光盘方面具有潜在的应用前景.利用射频磁控反应溅射技术, 通过调节衬底温度在沉积气压为0.2 Pa、氧氩比为2:3的条件下制备了一系列Ag₂O 薄膜.利用通用振子模型(包括1个Tauc-Lorentz振子和2个Lorentz 振子)拟合了薄膜的椭圆偏振光谱.在1.5-3.5 eV能量区间,薄膜的折射率在2.2-2.7之间, 消光系数在0.3-0.9之间. 在3.5-4.5 eV能量区间,薄膜呈现了明显的反常色散,揭示Ag₂O薄膜的等离子体振荡频率在 3.5-4.5 eV之间. 随着衬底温度的升高,薄膜的光学吸收边总体上发生了红移, 该红移归结于薄膜晶格微观应变随衬底温度的升高而增大. Ag₂O薄膜的光学常数表现出典型的介质材料特性.     

Fundamental parameter approach to XRF spectroscopy measurements of arsenic in polyester resin skin phantoms

A fundamental parameter (FP) approach that explicitly incorporates the energy‐broadening response of the detector was developed. The ratio between Kα fluorescence peak area and the sum of coherently and incoherently scattered peak areas was used as an indicator of trace element concentration. The peak ratio was theoretically calculated using the FP method. The energy‐broadening response curve of the Si(Li) detector was estimated by matching the theoretical and experimental values of this ratio. The method was implemented for the analysis of the K‐shell x‐ray fluorescence (K‐XRF) spectra of six polyester resin samples corresponding to six different arsenic concentrations. A ¹⁰⁹Cd radioactive source provided the excitation radiation for spectra acquisition. The predicted detector energy resolution expressed as full width at half‐maximum (FWHM) for Fe Kα fluorescence peak (208 ± 5 eV at 6.4 keV) and As Kα fluorescence peak (222 ± 5 eV at 10.5 keV) were in agreement with the experimental measurements. Copyright © 2008 John Wiley & Sons, Ltd.     

Electron stimulated desorption of cesium atoms from germanium-covered tungsten

The electron stimulated desorption (ESD) yield and energy distributions for Cs atoms from cesium layers adsorbed on germanium-covered tungsten have been measured for different Ge film thicknesses, 0.25-4.75 ML (monolayer), as a function of electron energy and cesium coverage Θ. The measurements have been carried out using a time-of-flight method and surface ionization detector. In the majority of measurements Cs is adsorbed at 300 K. The appearance threshold for Cs atoms is about 30 eV, which correlates well with the Ge 3d ionization energy. As the electron energy increases the Cs atom ESD yield passes through a wide maximum at an electron energy of about 120 eV. In the Ge film thickness range from 0.5 to 2 ML, resonant Cs atom yield peaks are observed at electron energies of 50 and 80 eV that can be associated with W 5p and W 5s level excitations. As the cesium coverage increases the Cs atom yield passes through a smooth maximum at 1 ML coverage. The Cs atom ESD energy distributions are bell-shaped; they shift toward higher energies with increasing cesium coverage for thin germanium films and shift toward lower energies with increasing cesium coverage for thick germanium films. The energy distributions for ESD of Cs from a 1 ML Ge film exhibit a strong temperature dependence; at T = 160 K they consist of two bell-shaped curves: a narrow peak with a maximum at a kinetic energy of 0.35 eV and a wider peak with a maximum at a kinetic energy of 0.5 eV. The former is associated with W level excitations and the latter with a Ge 3d level excitation. These results can be interpreted in terms of the Auger stimulated desorption model.