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121.
Xiaoying Zheng Jin Chen Jinhui Peng C. Srinivasakannan Rongsheng Ruan 《Phase Transitions》2018,91(3):308-315
In this work, we demonstrate a novel synthesis of synthetic rutile from high titanium slag. This rutile TiO2 was obtained by a simple one-step microwave roasting route. The influence of microwave roasting temperature and duration on the phase transformation of high titanium slag has been assessed. X-ray diffraction (XRD) results indicate that the intensity of anosovite (Fe3Ti3O10) phase, which were the major phase of high titanium slag of carbon thermal reduction of ilmenite ores, decreased rapidly while the peaks for rutile TiO2 phase increased with increase in the microwave roasting temperature. The scanning electron microscope (SEM) images revealed formation and the particle-size distribution of rutile TiO2 phase. Based on XRD and SEM analysis, confirmed the dependence of phase structure, composition and crystallite size on the process conditions of microwave roasting. 相似文献
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Wenchang Chu 《Mathematical Methods in the Applied Sciences》2023,46(1):830-839
An expansion formula into bivariate formal power series is established that implies, as consequences, three remarkable identities of partial theta functions due to Warnaar (2003), Schilling–Warnaar (2002) and Andrews–Warnaar (2007). 相似文献
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This work was undertaken to establish a quantitative analysis model which can rapid determinate the content of linalool, linalyl acetate of Xinjiang lavender essential oil. Totally 165 lavender essential oil samples were measured by using near infrared absorption spectrum(NIR), after analyzing the near infrared spectral absorption peaks of all samples, lavender essential oil have abundant chemical information and the interference of random noise may be relatively low on the spectral intervals of 7100-4 500 cm(-1). Thus, the PLS models was constructed by using this interval for further analysis. 8 abnormal samples were eliminated. Through the clustering method, 157 lavender essential oil samples were divided into 105 calibration set samples and 52 validation set samples. Gas chromatography mass spectrometry (GC-MS) was used as a tool to determine the content of linalool and linalyl acetate in lavender essential oil. Then the matrix was established with the GC-MS raw data of two compounds in combination with the original NIR data. In order to optimize the model, different pretreatment methods were used to preprocess the raw NIR spectral to contrast the spectral filtering effect, after analysizing the quantitative model results of linalool and linalyl acetate, the root mean square error prediction(RMSEP) of orthogonal signal transformation (OSC) was 0.226, 0.558, spectrally, it was the optimum pretreatment method. In addition, forward interval partial least squares (FiPLS) method was used to exclude the wavelength points which has nothing to do with determination composition or present nonlinear correlation, finally 8 spectral intervals totally 160 wavelength points were obtained as the dataset. Combining the data sets which have optimized by OSC-FiPLS with partial least squares(PLS) to establish a rapid quantitative analysis model for determining the content of linalool and linalyl acetate in Xinjiang lavender essential oil, numbers of hidden variables of two components were 8 in the model. The performance of the model was evaluated according to root mean square error of cross-validation (RMSECV) 9 root mean square error of prediction (RMSEP). In the model, RESECV of linalool and linalyl acetate were 0.170 and 0.416, respectively; RMSEP were 0.188 and 0.364. The results indicated that raw data was pretreated by OSC and FiPLS, the NIR-PLS quantitative analysis model with good robustness, high measurement precision; it could quickly determine the content of linalool and linalyl acetate in lavender essential oil. In addition, the model has a favorable prediction ability. The study also provide a new effective method which could rapid quantitative analysis the major components of Xinjiang lavender essential oil. 相似文献
125.
用于印刷电路板缺陷检测的光学视觉 总被引:4,自引:0,他引:4
本文提出了一种利用光学形态变换探测印刷电路板缺陷的新方法。以非相干光学相关器为基础,构成了一个实现印刷电路板微小缺陷检测的形态变换光学视觉系统给出了原理性实验结果。 相似文献
126.
K Porsezian 《Pramana》2001,57(5-6):1003-1039
In this review, considering the important linear and nonlinear optical effects like group velocity dispersion, higher order dispersion, Kerr nonlinearity, self-steepening, stimulated Raman scattering, birefringence, self-induced transparency and various inhomogeneous effects in fibers, the completely integrable concept and bright, dark and self-induced transparency soliton models in nonlinear fiber optics are discussed. Considering the above important optical effects, the different completely integrable soliton models in the form of nonlinear Schrödinger (NLS), NLS-Maxwell-Bloch (MB) type equations reported in the literature are discussed. Finally, solitons in stimulated Raman scattering (SRS) system is briefly discussed. 相似文献
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提出普遍定律和非普遍定律以及“协变”与“可导出”的明确定义,证明狭义相对性原理(及其伽利略近似)要求在惯性系变换下,自然界普遍定律是协变的,非普遍定律不协变但是“可导出”的,一切定律都服从相对性原理,从而进一步解答了由爱因斯坦,朗道关于狭义相对性原理的一种错误表述所引起的“协变性疑难”,还将有关结论推广到广义相对性原理情况。 相似文献