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显微数字全息中物光波前重建方法研究和比较 被引量:16
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作者 王华英 王大勇 +1 位作者 谢建军 王广俊 《光子学报》 EI CAS CSCD 北大核心 2007年第6期1023-1027,共5页
根据全息理论和线性系统理论,采用离轴无透镜傅里叶变换全息记录光路,对利用菲涅耳近似法、基于瑞利—索末菲衍射积分的卷积法以及角谱理论方法数值重建全息图进行了比较研究,并做了计算机模拟验证.结果表明:菲涅耳近似法和角谱方法重... 根据全息理论和线性系统理论,采用离轴无透镜傅里叶变换全息记录光路,对利用菲涅耳近似法、基于瑞利—索末菲衍射积分的卷积法以及角谱理论方法数值重建全息图进行了比较研究,并做了计算机模拟验证.结果表明:菲涅耳近似法和角谱方法重建像质比较好,且菲涅耳方法重建速度快;在记录距离极小的情况下,尽管记录距离不满足通常的菲涅耳近似条件,菲涅耳近似公式仍然成立;自由空间脉冲响应的快速傅里叶变换的性质与距离有关,由卷积方法得到的再现像只在某一特定距离下比较理想;对于极小物场、大孔径显微数字全息来说,菲涅耳近似重建方法是较为有效的方法. 展开更多
关键词 数字全息 显微数字全息 波前重建 菲涅耳近似 卷积法 角谱方法
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高数值孔径聚焦光穿过一个固体薄膜过渡区的远场衍射
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作者 陈亮 张耀举 +2 位作者 庄友谊 戴瑜兴 阮秀凯 《温州大学学报(自然科学版)》 2017年第1期39-46,共8页
运用矢量角谱方法和折射定律导出了高数值孔径菲涅尔波带片(FZP)聚焦光穿过一个固体薄膜过渡区的远场衍射表达式,应用所获得的公式研究了线性和径向偏振光经高数值孔径?-相位FZP聚焦后分别穿过硅薄膜过渡区和玻璃薄膜过渡区后进入空气... 运用矢量角谱方法和折射定律导出了高数值孔径菲涅尔波带片(FZP)聚焦光穿过一个固体薄膜过渡区的远场衍射表达式,应用所获得的公式研究了线性和径向偏振光经高数值孔径?-相位FZP聚焦后分别穿过硅薄膜过渡区和玻璃薄膜过渡区后进入空气的远场聚焦特性.结果显示,固体薄膜过渡区的存在,增加了聚焦系统的焦长,提高了FZP对径向偏振光的聚焦质量,降低了FZP对线性偏振光的聚焦质量. 展开更多
关键词 矢量衍射 菲涅尔波带片 界面 聚焦 角谱方法
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Highly Effective Detection of Amitraz in Honey by Using Surface-Enhanced Raman Scattering Spectroscopy Coupled with Chemometric Methods 被引量:1
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作者 Xin-ming Nie Jing Wang +4 位作者 Xun Wang Ya-ping Tian Si Chen Zhou-yang Long Cheng-hua Zong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第4期444-450,I0002,共8页
As an effective and universal acaricide, amitraz is widely used on beehives against varroasis caused by the mite Varroa jacobsoni. Its residues in honey pose a great danger to human health. In this study, a sensitive,... As an effective and universal acaricide, amitraz is widely used on beehives against varroasis caused by the mite Varroa jacobsoni. Its residues in honey pose a great danger to human health. In this study, a sensitive, rapid, and environmentally friendly surface-enhanced Raman spectroscopy method (SERS) was developed for the determination of trace amount of amitraz in honey with the use of silver nanorod (AgNR) array substrate. The AgNR array substrate fabricated by an oblique angle deposition technique exhibited an excellent SERS activity with an enhancement factor of -10^7. Density function theory was employed to assign the characteristic peak of amitraz. The detection of amitraz was further explored and amitraz in honey at concentrations as low as 0.08 mg/kg can be identified. Specifically, partial least square regression analysis was employed to correlate the SERS spectra in full-wavelength with Camitraz to afford a multiple-quantitative amitraz predicting model. Preliminary results show that the predicted concentrations of amitraz in honey samples are in good agreement with their real concentrations. Compared with the conventional univariate quantitative model based on single peak’s intensity, the proposed multiple-quantitative predicting model integrates all the characteristic peaks of amitraz, thus offering an improved detecting accuracy and anti-interference ability. 展开更多
关键词 AMITRAZ surface-enhanced Raman spectroscopy method Oblique angle deposition HONEY DETECTION SENSING Ag nanorod Density function theory Partial least squares regression
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Preliminary study in vitro brain tumor with high resolution magic angle spinning proton magnetic resonance spectroscopy 被引量:1
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作者 Wei Tan Yaojun Ke Guangyao Wu 《The Chinese-German Journal of Clinical Oncology》 CAS 2008年第2期103-106,共4页
Objective: To explore water soluble metabolite features of brain tumor specimens with HRMAS-^1HMRS and its potential clinical value. Methods: There were thirty cases of pathologically proven brain tumor, including 6... Objective: To explore water soluble metabolite features of brain tumor specimens with HRMAS-^1HMRS and its potential clinical value. Methods: There were thirty cases of pathologically proven brain tumor, including 6 Ⅰ-Ⅱ grade astrocytomas, 7 Ⅲ grade anaplastic astrocytomas, 10 IV grade glioblastomas and 7 meningiomas. Used Varian Company 600 MHz spectrometer with the Nano-probe for acquisition HRMASJHMRS, which was postprocessed with jMRUI 3.2 version software. These metabolic probability and their ratios to Cr were summed. Results: (1) HRMAS-^1HMRS could resolve NAA, PCr/Cr, GPC ± PCho ± Cho, Glu/GIn, Gly, Tau, Ala, Lac, ml and so on. All samples showed Lac, 6 samples showed unknown single peak at 3.72 ppm or 3.90 ppm. (2) The mean Cho/Cr of 6 Ⅰ-ⅡI grade astrocytomas was 2.42 ± 1.01 (P = 0.003, compared with glioblastoma). The mean Cho/Cr of 7 anaplastic astrocytomas was 3.48 ± 0.59 (P = 0.01, compared with glioblastoma). The Cho/Cr of 10 glioblastomas broadly ranged from 0.9 to 11.3 (mean 5.40 ± 1.23). From Ⅰ-Ⅱ grade astrocytoma to glioblastoma, Ala/Cr, Tau/Cr and Gly/Cr trends were increased; the mean Ala/Cr of glioma was 0.31 ± 0.13. (3) Meningiomas showed higher Ala and Cho. Their Cr was lower than that of gliomas. 4/7 cases had no NAA, 3/7 patients had lower NAA. Mean Cho/Cr was 3.56 ± 1.01, Ala/Cr was 0.53 ±0.28 (P = 0.006, compared with glioma). Conclusion: HRMAS-^1HMRS can show further details in vivo MRS, resolve in vivo spectroscopic metabolite of Cho compound and differentiate the extent of benign and malignant glioma. With the increase in the malignant degree of gliomas, Cho, ml, Ala, Tau and Gly will increase. HRMAS-^1HMRS is the only method of isotropic spectroscopy for pathological specimens. 展开更多
关键词 magic angle spinning high resolution proton magnetic resonance spectroscopy in vitro brain tumor
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