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为了对不同集成成像系统三维显示应用中的视觉分辨效果进行表征, 提出了一种基于人眼视觉的集成成像三维显示分辨率的分析比较方法. 通过分析集成成像三维显示系统的分辨率与人眼在最佳显示观看距离下分辨本领的关系, 定义了相对分辨率参数, 分析了其与集成成像三维显示实际观看时视觉分辨效果的关系. 研究结果表明, 透镜阵列的大小对集成成像三维显示的视觉分辨效果有重要的影响. 针对两个系统实例的理论计算结果表明, 系统间的相对分辨率参数差异是传统分辨率差异的1.75倍, 实验结果与理论分析一致. 该研究方法对三维显示分辨率的评价有一定的指导意义. 相似文献
123.
不同栝楼品种各药用部位无机元素含量比较 总被引:1,自引:0,他引:1
以山东道地药材栝楼为研究对象,分别对仁瓜蒌和糖瓜蒌两个品种皮、籽中Ca,Mg,Fe,Mn,Cu,Zn的含量进行分析测定;同时对雌、雄栝楼的天花粉中无机元素的含量进行研究。结果表明,两个栝楼品种中的微量元素含量在皮和籽中基本没有差别,但是不同无机元素的分布不一致。其中Ca在瓜蒌皮中的含量达到0.25%~0.28%,在籽中的含量为0.1%;而其它无机元素则基本以籽中的含量较高;雌栝楼天花粉中的微量元素含量明显高于雄栝楼天花粉,表明雌栝楼有较高的吸收或贮存无机元素的能力,原因可能与雌栝楼参与的生殖生长有较大关系。 相似文献
124.
In Na2HPO4-citric acid buffer solution, Cl2 can oxidize I− to form I2 and then it reacts with excess I− to form I3−. The I3− combines respectively with rhodamine dyes, including rhodamine B (RhB), butyl rhodamine B (b-RhB), rhodamine 6G (RhG) and rhodamine S (RhS), to form association particles which give stronger resonance scattering (RS) effect at 400 nm. The RS intensity of the RhB, b-RhB, RhG and RhS systems is proportional to chlorine concentrations in the range of 0.008-1.74, 0.019-1.33, 0.021-2.11 and 0.019-2.04 μg/mL Cl2, respectively. The detection limits of the systems were 0.0020, 0.0048, 0.0063 and 0.0017 μg/mL, respectively. In them, the RhB system has good stability and high sensitivity, and has been applied to the analysis of chlorine in drinking water, with satisfactory results which is in agreement with that of the methyl orange (MO) spectrophotometry. 相似文献
125.
Based on resonance scattering (RS) effect of rhodamine dye association particles, a new resonance scattering method for the determination of hydroxyl free radical from Fenton reaction was developed. In HCl-NaAc buffer solution, the OH of Fenton reaction oxidized the excess I− to I3−. The I3− combined, respectively, with rhodamine B (RhB), butyl rhodamine B (b-RhB), rhodamine 6G (RhG) and rhodamine S (RhS) to form association particles that exhibit stronger resonance scattering effect at 420 nm and 610 nm. However, the RS peak at about 610 nm was interfered with its synchronous fluorescence peak at 580 nm for RhB, 580 nm for b-RhB, 560 nm for RhG and 560 nm for RhS, respectively. The concentration of H2O2 in the range of 0.648-21.6 μmol/L, 0.423-13.0 μmol/L, 0.216-13.0 μmol/L and 0.092-13.0 μmol/L was linear to its resonance scattering intensity at 420 nm. Its detection limit was 0.15 μmol/L, 0.10 μmol/L, 0.092 μmol/L and 0.044 μmol/L, H2O2, respectively. This RhS RS method was applied to selection of the antioxidant, with satisfactory results. 相似文献
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ZHONG Han-Yu WANG Tian-Tian ZHANG Yi-Kai CHEN Huan LV Zhi-Liang ZHANG Ming-Feng GENG Dong-Ping NIU Chun-Juan LI Ke 《结构化学》2011,30(12):1737-1741
The title compound(ethyl 3-(4-methoxyphenyl)-4-oxo-3,3a,4,6-tetrahydro-1H-furo[3,4-c]pyran-3a-carboxylate) has been synthesized,and its crystal structure was characterized by X-ray single-crystal diffraction.The crystal belongs to monoclinic,space group P21/n,with a = 10.124(4),b = 11.754(4),c = 13.792(5) ,β = 111.533(3)o,V = 1526.6(10) 3,Z = 4,C17H19O6,Mr = 319.32,Dc = 1.389 g/cm3,F(000) = 676,λ(MoKα) = 0.71073 ,μ = 0.105 mm-1,R = 0.0660 and wR = 0.2027 for 2993 observed reflections(I > 2σ(I)).The compound shows potent anti-tumor activity in vitro. 相似文献
129.
Shen ZL Goh KK Wong CH Yang YS Lai YC Cheong HL Loh TP 《Chemical communications (Cambridge, England)》2011,47(16):4778-4780
An efficient method for the synthesis of ester-containing indium homoenolate via a direct insertion of indium into β-halo ester in the presence of CuI/LiCl was described. The synthetic utility of the indium homoenolate was demonstrated by palladium-catalyzed cross-coupling with aryl halides in DMA with wide functional group compatibility. 相似文献
130.
Zhen Wu Xue-Xin Feng Qing-Dong Wang Xuan-Yu Liu Weidong Rao Jin-Ming Yang Zhi-Liang Shen 《中国化学快报》2020,31(2):391-395
An efficient water-based bismuth-mediated addition reaction of carbonyl compound with cyclic allylic halide was developed.The reactions proceeded smoothly in aqueous DMF in the presence of ammonium iodide to afford the corresponding syn-homoallylic alcohols in moderate to good yields with excellent diastereoselectivities(>99:1 syn:anti).Reversal of product diastereoselectivity was observed when heteroaryl aldehyde possessing an adjacent chelating nitrogen atom was employed as substrate. 相似文献