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171.
Jovana Šakota Rosić Jelena Munćan Ivana Mileusnić Boris Kosić Lidija Matija 《Soft Materials》2016,14(4):264-271
The aim of this study was to determine if it is possible to distinguish between the groups of spoiled and unspoiled soft contact lenses using near-infrared spectroscopy and new analytical approach – Aquaphotomics. Using the principal component analysis, it was established that the absorbance spectra of worn and new contact lenses are differed at water absorption band related to hydration of proteins. Detection of proteins thus was performed indirectly by using vibrations of water molecules. This exploratory study showed that near-infrared spectroscopy and Aquaphotomics have potential for non-invasive, chemical-free detection of protein deposits on hydrated soft contact lenses. 相似文献
172.
针对红外图像具有分辨率低、帧频高的特点,以及目标特性分析和图像处理算法验证需要完整、无损记录图像数据的要求,提出了一种高速数字图像传输记录系统方案。方案采用HOTLinkⅡ+FPGA+PCI的体系结构,数据通过同轴线从红外图像设备传输到图像记录设备的CYP15G0101芯片,实现了远距离的点到点可靠传输和解码。FPGA和PCI接口芯片对图像数据进行接收和缓冲,工控机软件通过调用PCI SDK提供的API函数实现对PCI接口芯片的初始化、控制和数据传输等操作,从而将图像数据按照预定的格式连续地写入物理上连续的硬盘存储空间,最终实现数据记录、回放和分析等功能。该方案已经成功应用于某型红外图像记录设备并经过长时间测试,记录时间、漏记率等指标和回放等功能均满足研制要求。 相似文献
173.
VIS-NIR spectroscopy combined with multivariate analysis after the appropriate spectral data pre-treatment has been proved to be a very powerful tool for judgment of the relative pattern of the objects that have very similar properties. In this study, seventy transgenic tomatoes with antisense LeETR2 and 94 of their parents, non-transgenic ones were measured in VIS-NIR diffuse reflectance mode. Principal component analysis (PCA), discriminant analysis (DA) and partial least-squares discriminant analysis (PLSDA) were applied to classify tomatoes with different genes into two groups. Calibrations were developed using PLS regression with the leave-one-out cross-validation technique. The results show that differences between transgenic and non-transgenic tomatoes do exist and excellent classification can be obtained after optimizing spectral pre-treatment. The correct classifications for transgenic and non-transgenic tomatoes were both 100% using PLSDA after derivative spectral pre-treatment. The raw spectra with PLSDA model after the second derivative pre-treatment had the best satisfactory calibration and prediction abilities, with rc = 0.97964, root mean square error of calibration (RMSEC) = 0.099, rcv = 0.97963, root mean square error of cross-validation (RMSECV) = 0.0993 and a factor. The results in the present study show VIS-NIR spectroscopy together with chemometrics techniques could be used to differentiate transgenic tomato, which offers the benefit of avoiding time-consuming, costly and laborious chemical and sensory analysis. 相似文献
174.
175.
The absorption,transmission and reflection spectra of spin-coated films of Ni(azo)2 (azo nickel chelate) were measured. Because of the intermolecular aggregation,the absorption peak of Ni(azo)2 thin film has a red-shift of about 40 nm with respect to that of it in methanol solution. The fabricated optical disk showed a reflectivity of 48% and its carrier-noise ratio (CNR) was greater than 45 dB when recording with 7.5 mW laser power at the wavelength of 780 nm. 相似文献
176.
177.
本文利用光在多层膜介质中的传播模型,计算了可录型光盘(CD R)中染料媒体的光学特性.表明在适合于CD R光盘记录的780nm波长处,由于多层膜中光的干涉作用,样品反射率随薄膜的厚度变化发生振荡.振荡的幅度和周期依赖于染料薄膜的复数折射率(n+ik).当记录介质层的复数折射率在2.1+i0.02至2.8+i0.12之间时,能够满足CD R光盘对染料介质的要求.通过对三种菁染料薄膜的光谱性质分析及光学参数的模拟计算,证实了该方法用于染料薄膜光学特性研究的合理性.并为选择适合于光记录的染料薄膜的厚度范围提供了简便的方法 相似文献
178.
179.
A system for holographic interferometry using bacteriorhodopsin films as an erasable optical recording medium is presented. Bacteriorhodopsin is a photochromic protein found in archaebacteria. Bacteriorhodopsin films with an aperture of 90×90 mm are used for high-resolution lensless recording (5000 lines/mm). The holograms are recorded in reflection-type geometry in order to achieve a compact design. A frequency-doubled Nd : YVO4 laser, emitting at 532 nm, is used for recording and incoherent blue light is employed for photochemical erasure. The system is suitable for a variety of different interferometric techniques like double-exposure, time-averaging and real-time interferometry. As an example for the application of the BR-based non-destructive testing system the inspection of ceramic motor valves, made from silicone nitride (Si3N4), under mechanical load is reported. 相似文献
180.
Krzysztof B. Be Justyna Grabska Christian W. Huck Sylwester Mazurek Mirosaw A. Czarnecki 《Molecules (Basel, Switzerland)》2021,26(22)
Mid-infrared (MIR) and near-infrared (NIR) spectra of crystalline menadione (vitamin K3) were measured and analyzed with aid of quantum chemical calculations. The calculations were carried out using the harmonic approach for the periodic model of crystal lattice and the anharmonic DVPT2 calculations applied for the single molecule model. The theoretical spectra accurately reconstructed the experimental ones permitting for reliable assignment of the MIR and NIR bands. For the first time, a detailed analysis of the NIR spectrum of a molecular system based on a naphthoquinone moiety was performed to elucidate the relationship between the chemical structure of menadione and the origin of the overtones and combination bands. In addition, the importance of these bands during interpretation of the MIR spectrum was demonstrated. The overtones and combination bands contribute to 46.4% of the total intensity of menadione in the range of 3600–2600 cm−1. Evidently, these bands play a key role in shaping of the C-H stretching region of MIR spectrum. We have shown also that the spectral regions without fundamentals may provide valuable structural information. For example, the theoretical calculations reliably reconstructed numerous overtones and combination bands in the 4000–3600 and 2800–1800 cm−1 ranges. These results, provide a comprehensive origin of the fundamentals, overtones and combination bands in the NIR and MIR spectra of menadione, and the relationship of these spectral features with the molecular structure. 相似文献