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951.
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We introduced an easy approach to realize the Laplacian first-order and second-order differential of the object wave in transverse direction by use of one in-line digital hologram. It can be used for pinpoint the position of the objects. 相似文献
954.
Blockcopolymer (BCP) lithography is an emerging nanolithography technique for fabrications of various nanoscale devices and materials. In this study, self-assembled BCP thin films having cylindrical nanoholes were prepared on gold by surface neutralization using self-assembled monolayer (SAM). Oxygen plasma treatment was investigated as a way to enhance the functionality of Au surface toward SAM formation. After surface neutralization, well-ordered nanoholes with 9 to 20 nm diameters were formed inside BCP thin films on Au surfaces through microphase separation. The effects of oxygen plasma treatment on the formation of BCP nanopattern were investigated using surface analysis techniques including X-ray photoelectron spectroscopy (XPS) and water contact angle measurement. Au nanodot arrays were fabricated on gold film by utilizing the BCP nanotemplate and investigated by atomic force microscopy (AFM). 相似文献
955.
基于近红外光谱的人参与西洋参的快速鉴别研究 总被引:5,自引:0,他引:5
基于近红外光谱分析技术结合模式判别方法建立了一种人参和西洋参鉴别的新方法。收集根状、根须和粉末状的样品共90份,在有聚乙烯包装袋的情况下直接采集近红外光谱,去除原始光谱中包装袋的显著吸收后进行了MSC与一阶导数处理,然后采用移动窗口偏最小二乘法选择了建模光谱区间,分别建立了PLS-DA,PCA-DA和SVM判别模型,并对3种模型作了对比分析,结果表明SVM判别效果最优,其对预测集的正确判别率为100%。该方法准确、便捷,可实际应用于企业原料药材的质量控制,实现对原料药材的快速筛查。 相似文献
956.
Dong-Cheol Woo Chi-Bong Choi Sung-Ho Lee Eunjung Bang Sang-Soo Kim Hyang-Shuk Rhim Sang-Young Kim Bo-Young Choe 《Applied magnetic resonance》2010,38(1):65-74
The purpose of this study was to characterize the neurochemical profiles of various parts of the canine brain using proton nuclear magnetic resonance spectroscopy, tissue extraction, and external simulated phantom concentration quantification. The occipital, frontal, and temporal lobes, thalami, cerebellar cortices, and spinal cords of five pure bred adult beagles were collected, and heavy water solutions for the nuclear magnetic resonance sample were prepared using the methanol–chloroform–water extraction method. The metabolite concentrations in canine brain tissues were measured and compared with those found in human and rat brain tissues. In addition, the cross peaks of Lac, Glu/Gln, and mIns were identified using two-dimensional correlation spectroscopy in the canine frontal cortex. The present study demonstrated the absolute quantification of canine neuronal parts using in vitro high-resolution magnetic resonance spectroscopy, with tissue extraction used to accurately measure metabolite concentrations, thus providing valuable metabolic information regarding the various canine neuronal regions. 相似文献
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Shih-Ming Hsu Hsi-Wen Yang Yung-Hui Huang Jeng-Hung Lee Chun-Yen Yu Yi-Jen Liao Shick-Kai Hung Moon-Sing Lee 《Radiation measurements》2010,45(3-6):553-555
Thermoluminescent dosimeters are widely applied in the measurement of radiation dose. Since the luminescent centers are not lost during the reading process, radiophotoluminescent glass dosimeters (RPLGDs) can be repeatedly readout. The aims of this study were to make RPLGD and to analyze its physical and chemical properties. This study used chemical compounds such as Na3PO4, AlPO4, AgCl, AgNO3, B2O3, H3PO4 and P2O5 as the main ingredients. Depending on the self-fabricated glass compounds, the melting temperatures were between 1100 and 1500 °C. When the 0.1 mol% of silver was added, the radiation detection of self-fabricated RPLGD reached to the highest sensitivity. However, when silver concentration was larger than 0.1 mol%, the radiation detection sensitivity plummets rapidly. Excess amounts of silver and aluminum decreased the penetrate capability of ultraviolet spectrum. Based on our study, we found that chemical compound concentrations and melting process, which all affect radiation sensitivity and stability of self-fabricated RPLGD. 相似文献
959.
Shu Yin Peilin Zhnag Bin Liu Xiangwen Liu Tsugio Sato Dongfeng Xue Soo Wohn Lee 《Research on Chemical Intermediates》2010,36(1):69-75
Nitrogen-doped titania (TiO2−xNy) nanoparticles with monoclinic phase were successfully prepared by a microwave-assisted hydrothermal process. The obtained TiO2−xNy powders showed high specific surface area, fine particle size, and excellent photocatalytic ability for the oxidative destruction of nitrogen monoxide under irradiation of monochromatic LED light with various wavelengths. 相似文献
960.