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41.
朱遵尚  苑云  李由  尚洋  于起峰 《光学学报》2014,34(2):211002-94
针对嫦娥一号探月卫星2C级月面成像,提出了基于待配点最优模板选择的二次函数形变补偿迭代匹配方法。仿真表明它能有效地适应地形起伏引起的图像形变,匹配精度较高且稳定性好。在标准相关匹配的基础上结合所提出的方法完成了下视图与前、后视图的精确匹配,采用三视约束机制和顺序检验机制保证了匹配的稳健性。分析了线阵相机成像的仿射近似模型,并以此为基础实现同轨三视重建。基于邻轨下视图同名特征点,采用RANSAC方法估计邻轨三维坐标转换参数,完成邻轨拼接。实验结果表明,三维重建的月貌图能够更好地表达月球表面的形状和地形。  相似文献   
42.
Ladder polysiloxanes (LPS) including both oxygen-bridged ladder polysilsesquioxanes (LPSQ) and organo-bridged ladder polysiloxanes (OLPS) are very important materials because of their excellent properties1. Adrianov et al. in 1960 attempted to prepare 1, …  相似文献   
43.
Novel NaA/carbon nanocomposite thin films were successfully prepared on a porous a-Al2O3 substrate by incorporatingnanosized NaA zeolite into novolak-type phenolic resin.The prepared films were characterized by XRD,SEM and single gaspermeation tests.The NaA zeolite/carbon nanocomposite thin films exhibited that the ideal separation factor of CO2/CH4 was 28.4and the carbon dioxide flux was 3.39*10-7mol/(Pa m2s)at room temperature and under a pressure difference of 100 kPa,whichwas two orders of magnitude higher than that of pure carbon membrane prepared at the same procedures and conditions as those ofcomposite films.From the SEM images,the films were continuous and highly intergrown.Compared with carbon membranes,thethickness of nanocomposite films was drastically decreased,which was helpful to reduce the diffusion resistance and increase theflux of gas permeance.  相似文献   
44.
A rapid and sensitive method for the analysis of three catecholamines by capillary electrophoresis(CE)with directchemiluminescence(CL)detection is described.The detection limits(S/N=3)were 1.3*10-8g/mL for isoprenaline,1.0*10-8g/mL for epinephrine and 2.8*10-8g/mL for dopamine.The proposed method was successfully applied to theanalysis of catecholamines in urine samples of cigarette smokers and nonsmokers.The results showed that there is a close relationbetween the release of dopamine in human body fluids and cigarette smoking/nonsmoking.  相似文献   
45.
To enable insulin as multi-drug carrier, we designed and synthesized dendritic linker molecule bearing three 5-Fluorouracil residues at the branch ends. The new conjugate showed excellent water solubility. The stabilities under different conditions were investigated. The results showed that the conjugate was a potential prodrug to release free 5-Fu.  相似文献   
46.
Benzimidazole compounds have attracted a renewed interest recently owing to theirpotential applications in high-performance composite materials, electronic chemicals,photosensitive materials, and their special potentials in biological and/or medicinalapplication1,2. Typically, aromatic compounds with near planar structures and contain-ing hydrogen-donor groups or groups, which are capable of being protonated, havespecial interactions with DNA via intercalation, hydrogen-bonding, and so on3.Me…  相似文献   
47.
Two different skeletons of heterocyclic compounds,quinoline and quinazolinone analogs could be obtained by a novel one-pot synthesis from substituted 3-amino-1 H-benzo[f]chromene-2-carbonitrile derivatives and cyclohexanone in DMF in the catalyst of anhydrous zinc chloride under reflux.A plausible mechanism was proposed.  相似文献   
48.
Great attention is currently paid to the synthesis of polynuclear transition metal complexes as well as their photochemical, photophysical, and electrochemical properties. The design of multicomponent systems capable of performing useful light- and/or redox-induced function is of special interest1. The oxo-centered carboxylate-bridge trinuclear ruthenium clusters have been investigated extensively during recent decades because they have remarkable electron-transfer properties, intense visibl…  相似文献   
49.
Andrographolide (Andro) (Figure 1) is a diterpene lactone isolated from Andrographis paniculate Nees1. It has showed several biological activities including analgesic, antipyretic and anti-inflammatory effects2. However, its poor water solubility and unstability towards oxygen restrained its application. In pharmaceutics, b-CD is used to increase solubility and stability3. We have prepared the inclusion compound of Andro/b-CD (Figure 2) under microwave irradiation4. It has been found…  相似文献   
50.
靶场光测图像处理的一个突出难题是如何分辨图像上出现的大量小目标。利用单站序列图像上目标的运动关联、目标在多站图像上像点之间的对极几何约束关系,提出了靶场多站图像多目标判读的新技术,采用单站序列图像目标卡尔曼运动轨迹预测及跟踪识别技术,以及多站图像对极几何约束同名目标匹配技术,突破了传统方法仅进行单站图像判读的局限。仿真结果证明其能有效解决多站、多目标的判读问题,已成功应用于我们研制的多套靶场图像判读系统中。  相似文献   
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