晶相形成对TiSi2薄膜光学性能的影响

通过常压CVD方法由SiH4和TiCl4直接在玻璃基板上成功制备了TiSi2薄膜,用XRD、FESEM、四探针测阻仪和分光光度计研究了薄膜的结构、形貌、电学和光学性能。研究表明TiSi2薄膜的晶相是面心正交型TiSi2;薄膜的电阻率直接由晶相的形成决定,受晶相颗粒大小和晶相致密度控制,TiSi2薄膜的电阻率随薄膜中TiSi2晶相含量的增大而下降。TiSi2薄膜在400~750nm范围的可见光区具有大致相同的透射比和最小的反射比,薄膜的透射比随薄膜厚度的增加而减小。在大于750nm的红外区,薄膜电阻率越小,对红外辐射的反射比越高,且随着波长增加至25000nm,TiSi2薄膜的反射比逐渐上升到约0.95。     

基于紫外分光光度法的阳西电厂污染源自动监测系统

介绍了紫外分光光度法测定化学需氧量(COD)的特点与功能,紫外分光光度法测定COD具有投资小、运行费用低、无化学污染、监测快速、操作简便等优点。并介绍了紫外分光光度法COD测定仪在广东阳西电厂污染源监测系统中的应用,通过与pH测定仪、流量计的联合监测,完成当地环保部门对阳西电厂污染总量控制。     

红外分光光度计测量太阳吸收涂层80℃的发射比

采用红外分光光度计和专门设计的试片恒温器测量80℃时太阳选择性吸收涂层及金属涂层的反射光谱,采用黑体辐射普朗克函数积分计算得到该温度下试样的发射比。试样采用磁控溅射法在平面玻璃载片上制备。实际测量结果表明,该方法测量精度高,测量过程简便快捷。另外,红外分光光度计为通用仪器,反射光谱标样容易制备和计量校准。     

太阳选择性吸收涂层的中温法向发射比测试对比

采用紫外-可见光-红外分光光度计、傅里叶红外光谱仪,在室温条件下,测量Mo-SiO2太阳选择性吸收涂层在空气300℃退火前后0.34～25.00μm波长范围内的近法向反射光谱曲线。假设室温和高温条件下光谱反射特性不变,根据基尔霍夫定律计算出涂层在不同温度下的法向发射比。采用辐射计法,测量同一片样品在200℃、300℃时的法向发射比,两种方法得出的数值差异仅为0.02～0.03。经误差分析发现,在保证涂层退火前后反射光谱曲线不变、工作温度不超过300℃的情况下,基于室温反射光谱曲线和中温辐射计法的结果在测试仪器的误差范围内基本等效。     

UV-3600分光光度计测量太阳能用玻璃的透射比研究

本文讨论用岛津UV-3600分光光度计测量太阳能用玻璃透射比研究,参照GB／T25968-2010《分光光度计测量材料的太阳透射比和太阳吸收比试验方法》,对不同类型的玻璃透射比进行测量,通过对不同玻璃透射比的测定,了解UV-3600分光光度计测量玻璃的透射时需要注意的事项,为准确测量玻璃的透射提供一些参考。     

紫外线知识讲座--紫外线的测量及其标准

1 关于紫外辐射的测量仪器 由于紫外辐射中散射量值几乎占到了总量的近一半，所以在紫外辐射的测量中，均以测量其总辐射(即直接辐射 散射辐射)作为主要目标。太阳紫外线的测量与太阳辐射测量一样，区分为分光辐射测量与总量测量。在分光辐射测量中，根据所用的手段又可分为利用窄带滤光片的固定波长测量与     

氮氩比对AlNx薄膜微观结构与光学性质的影响

利用射频反应磁控溅射技术制备了氮化铝( AlNx)薄膜.采用X射线衍射仪、扫描电子显微镜、紫外-可见-近红外分光光度计分析氮氩比对AlNx相结构、表面形貌、沉积速率以及薄膜光谱透过率的影响规律.氮氩比显著影响溅射薄膜的成分和相组成,进而影响薄膜的透过率.当氮氩比小于4/156时,薄膜由金属铝组成;当氮氩比大于6/154时,薄膜由立方-AlN相组成.薄膜形貌随氮氩比例增大由粗糙不规则状的颗粒转化为均匀致密的细小颗粒,AlNx薄膜的沉积速率随之减小.光学性能测试结果表明,AlNx薄膜透过率由金属铝膜的零增加为83％,AlNx薄膜在300～2500nm波长范围内透过率较高,而在大于2500nm的近红外区透过率显著下降.     

华北平原北部太阳辐射及地表辐射平衡特征——基于河北固城站的试验观测研究

利用位于河北定兴县的中国气象局固城生态与农业试验站2005年7月～2007年2月期间观测的太阳辐射各分量的资料,详细分析了该站太阳辐射及地表反射的基本特征.分别对到达地表的太阳总辐射、地面反射短波辐射、地表反射率、净辐射、光合有效辐射和紫外辐射(UV-B)的日、年变化特征进行了分析,揭示了该地区的辐射平衡特征.同时分析并给出了光合有效辐射和紫外UV-B辐射占太阳总辐射比值的变化规律.     

内聚光CPC热管式真空集热管的光学效率分析

针对内聚光CPC热管式真空集热管,根据其结构建立详细完整的光学效率模型,采用光学追迹、几何光学分析等方法对模型中的各项参数(几何光学效率、透射比、反射比、吸收比等)进行分析研究。在此基础上,针对所研制的集热管构建出以太阳辐照强度、太阳光入射角为参变量的光学效率模型,并根据计算的数据结果对集热管进行相关分析。所建立的模型可为各种集热器的光学效率分析提供参考。     

紫外可见分光光度法在渔业环境监测中的应用

介绍紫外可见分光光度法在渔业环境监测中的应用,主要包括水体、沉积物及生态环境监测3部分,它可测定营养盐、叶绿素a、硫化物、氰化物和油类等多个指标,在渔业环境监测工作中发挥着极为重要的作用。     

Transparent heat mirrors based on tungsten oxide-silver multilayer structures

Transparent heat mirrors based on tungsten oxide/silver three-layer structures were fabricated using thermal evaporation. The optical and morphological properties of the single layers were first investigated to serve as a basis for the fabrication of the heat mirrors. Only silver films with a thickness higher than 18 nm were found to be continuous. Subsequently, WO₃/Ag/WO₃ multilayers were deposited, where the WO₃ layers thickness was fixed at 35 nm, and the thickness of the silver layer was varied from 18 to 39 nm. The optical properties of the multilayers were measured over the visible and near infrared ranges. These multilayers exhibited the desired heat mirror behavior, namely the transmittance was largely confined to the visible range and the reflectance was diminished in that range. The maximum visible transmittance was 88.3% at 554 nm. Increasing the thickness of the silver films resulted in a decrease of the visible transmittance, with a corresponding increase in the infrared reflectance. Optimization of these two opposing trends was evaluated using a figure of merit, from which the best performance was obtained for multilayers with a silver layer of thickness of 24 nm.     

Electrical and optical properties of F-doped textured SnO2 films deposited by APCVD

This paper presents the structural, electrical and optical properties of transparent conducting F-doped textured SnO₂ films prepared by atmosphere pressure chemical vapour deposition (APCVD). Polycrystalline SnO₂:F films having a variable preferred orientation have been obtained with resistivity as low as 5 × 10⁻⁴ Ωcm, with carrier concentrations between 3.5 × 10²⁰ and 7 × 10²⁰ cm⁻³, and Hall mobilities from 15.7 to 20.1 cm²/V/s. The average transmittance (including diffusion transmittance) is as high as 94% in the wavelength range of the visible spectrum and the maximum infrared reflectance reaches 92% for a film 655 nm thick. The figure of merit ƒ_TC = T10/_sh, (7.12 × 10⁻² S) of these films is the highest amongst the results reported on doped SnO₂ films.     

Solution growth, characterization and applications of zinc sulphide thin films

Zinc sulphide (ZnS) thin films were successfully deposited on glass substrates under varying deposition conditions using the electroless or solution growth technique. The film properties investigated include their transmittance/reflectance/absorbance spectra, bandgap, optical constants, and thicknesses. Films grown under certain parametric conditions were found to exhibit high transmittance ( 64–98%), low absorbance, and low reflectance in the ultraviolet (uv)/visible/near infrared (nir) regions up to 1.00 μm. Those obtained under other conditions exhibited high transmittance ( 78–98%) and low absorbance ( 0.01–0.1) in the uv/visible regions but low transmittance ( 30–37 and high absorbance ( 0.56) in the nir region. These characteristics revealed their suitability for various solar device applications. Bandgap range E_g 3.7–3.8 eV and thickness range t 0.07 – 0.73 μm were obtained.     

Synthesis of cobalt–silicon oxide thin films

Silicon–cobalt oxide thin films were prepared by the dipping sol–gel process. Samples with different number of dipping–annealing cycles were prepared. Some data regarding the precursor sol are given from small angle X-ray scattering characterization. Composition, structure, surface morphology and optical properties are obtained from X-ray diffraction, reflectance, transmittance, FTIR, scanning electron microscopy and EDX spectroscopy measurements. The silicon–cobalt oxide thin films prepared in this work are mostly amorphous. They have a high absorption coefficient in the visible and infrared regions. A refractive index from 2.15 to 1.79 (at 1200 nm wavelength), and a band gap between 3.73 and 3.68 eV with increasing film thickness were measured in the films. Sol–gel prepared Si–Co oxide thin films could be well suited for use in photothermal solar collectors.     

Sb–Cu–Li electrochromic mirrors

Switchable mirrors offer significant advantages over traditional electrochromic devices for control of incident light in architectural and aerospace applications due to their large dynamic ranges in both transmission and reflection in the visible and near infrared regimes. Here we describe construction and spectroscopic characterization of a complete electrochromic mirror device consisting of an antimony–copper alloy (40 at% Cu) active electrode coupled with an optically passive vanadium oxide counter electrode and a crosslinked polymer gel electrolyte. Transmittance and reflectance spectra in the visible–near IR (300–2500 nm) in both mirror and transparent states are reported. The photopic transmittance of the complete device varied from less than 3% to more than 20% during cycling, requiring about 40 min for complete switching in each direction. At the same time, the photopic reflectance varied from 40% to 25%. The crosslinked polymer improves the stability of the mirror electrode relative to that in a liquid electrolyte.     

Hydrogen absorption by metallic thin films detected by optical transmittance measurements

The hydrogen absorption by bilayers of Pd/Nb and Pd/Ti, grown on glass substrates, was studied by measuring changes in optical transmittance and reflectance in the visible range (wavelengths between 400 nm and 1000 nm) of the films at hydrogen pressures between 3.99 × 10² and 4.65 × 10⁴ Pa. The electrical resistance of the films was also measured during absorption to correlate with the optical data. All the films were grown by a controlled sputtering technique in high vacuum. Pd films ranging in thickness between 4 nm and 45 nm were also characterized when the films were exposed to a hydrogen pressure. The resistance and transmittance of all the Pd samples increased with the uptake of hydrogen until saturation occurred. For Pd/Ti bilayers, fast uptake of hydrogen was deduced from a transmittance increase, indicating hydrogen absorption in the Ti layer. In the case of the Pd/Nb bilayer, a decrease in transmittance was observed, indicating that hydrogen was not absorbed in the Nb layer. The transmittance decrease could be explained by a reduction of Nb native oxide by the hydrogen at the surface.     

红外灯辅助喷雾热解法制备可控锑掺杂氧化锡透明热反射薄膜

本文以乙二醇为溶剂及配位剂,以冰乙酸为酸性催化剂,采用溶胶−凝胶法制备均一稳定的具有不同锑掺杂浓度的二氧化锡（SnO2）溶胶,再通过红外灯辅助喷雾热解法制备性能优异的可控锑掺杂SnO2薄膜,并对薄膜微结构、光电性能进行表征。结果表明：薄膜以四方金红石结构存在,结晶完全;方阻值随锑掺杂浓度和成膜厚度的增加而降低;薄膜在可见光区的平均透过率可达79%左右,且在中远红外光区的平均反射率可达80%左右。此外,通过改变锑掺杂浓度和成膜厚度,能够有效地调节薄膜的红外反射率与反射起点波长,从而满足不同气候条件对热反射和热发射的不同要求。     

ZnS/Me heat mirror systems

Selective spectral transmittance and heat conversion efficiencies of some heat-mirror systems consisting of ZnS/Me (Me=Al or Ag) under different configuration were studied. The 15 nm ZnS/20 nm Ag system has optimal selective spectral transmittance in the visible wavelength range and the highest reflection in the infrared wavelength range. For this system, Ag can keep its optical characteristics after heating at 200°C by the protection of the thick ZnS layer. The system consisting of 15 nm ZnS/10 nm Al is the most efficient heat mirror of the ZnS/Al systems.     

Energy-saving transparent heat mirrors based on tungsten oxide–gold WO3/Au/WO3 multilayer structures

Transparent heat mirrors are multilayer structures that transmit visible light while reflecting infrared heat. Heat mirrors based on tungsten oxide and gold multilayers WO₃/Au/WO₃ were fabricated by thermal evaporation, and their performance was investigated as a function of the thickness of the gold layer. First, the properties of individual layers were investigated. Atomic force microscopy revealed that all layers possessed smooth surfaces that were suitable for optical applications. The transmittance of the gold layers was found to decrease as the thickness is increased, with an opposite trend followed by infrared reflectance. In the multilayers, the thickness of the WO₃ was fixed at 34 nm, whereas the thickness of the gold layers was varied in the range 20–44 nm. X-ray photoelectron spectroscopy was used to investigate the elemental diffusion among the various layers, and it revealed the presence of inter-diffusion of elements throughout the layers. The performance of the heat mirrors was evaluated on the basis of their optical behavior. The optimum thickness of the gold layer was found to be 36 nm, with a peak spectral transmittance of 84%.