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1.
针对微结构和微光学元件等微小物体的表面定量检测,本文介绍了一种利用无透镜数字全息的快速、无损的显微成像方法。首先介绍了基于球面波的无透镜数字全息显微成像技术的基本原理,采用CCD作为光电转换器件,基于迈克尔逊干涉光路,设计了无透镜数字全息显微成像系统,利用反射镜构成折反式光路,系统结构简单、紧凑,提升了系统便携性。然后利用USAF1951分辨率板对构建的成像系统进行了标定实验,得出其横向分辨率为6.69μm,放大倍率为3.375,系统工作距离为12.0mm。此外,还对晶圆表面结构进行实际测量。实验验证了该系统的可行性和有效性,有望进一步应用于MEMS、微光学元件、光学元件等表面形貌的定量测量中。  相似文献   

2.
Sha等在静态池实验中观察到了转动能量转移中的碰撞量子干涉,并且计算了决定跃迁散射截面的积分干涉角(J.Chem.Phys.,1995,102:2772).由于积分干涉角是微分干涉角的平均效应,为了得到更精确的信息,进行了分子束实验.作者文运用含时微扰的一级波恩近似理论,提出了衡量干涉程度的1П态双原子分子中关于Λ量子干涉的微分干涉角.利用各向异性相互作用势计算了其干涉角.得到分子束实验中微分干涉角随实验参数,包括实验温度、碰撞伴、作用距离和转动量子数变化的关系.并且讨论了影响干涉角的各种参数.此理论模型对理解和进行分子束实验是非常重要的.  相似文献   

3.
Sha等在静态池实验中观察到了转动能量转移中的碰撞量子干涉,并且计算了决定跃迁散射截面的积分干涉角(J.Chem.Phys.,1995,102:2772).由于积分干涉角是微分干涉角的平均效应,为了得到更精确的信息,进行了分子束实验.作者文运用含时微扰的一级波恩近似理论,提出了衡量干涉程度的^1П态双原子分子中关于Λ量子干涉的微分干涉角.利用各向异性相互作用势计算了其干涉角.得到分子束实验中微分干涉角随实验参数,包括实验温度、碰撞伴、作用距离和转动量子数变化的关系.并且讨论了影响干涉角的各种参数.此理论模型对理解和进行分子束实验是非常重要的.  相似文献   

4.
Sha等在静态池实验中观察到了转动能量转移中的碰撞量子干涉,并且计算了决定跃迁散射截面的积分干涉角(J.Chem.Phys.,1995,102:2772).由于积分干涉角是微分干涉角的平均效应,为了得到更精确的信息,进行了分子束实验.作者文运用含时微扰的一级波恩近似理论,提出了衡量干涉程度的1П态双原子分子中关于Λ量子干涉的微分干涉角.利用各向异性相互作用势计算了其干涉角.得到分子束实验中微分干涉角随实验参数,包括实验温度、碰撞伴、作用距离和转动量子数变化的关系.并且讨论了影响干涉角的各种参数.此理论模型对理解和进行分子束实验是非常重要的.  相似文献   

5.
Sha等在静态池实验中观察到了转动能量转移中的碰撞量子干涉,并且计算了决定跃迁散射截面的积分干涉角(J.Chem.Phys.,1995,1022772).由于积分干涉角是微分干涉角的平均效应,为了得到更精确的信息,进行了分子束实验.作者文运用含时微扰的一级波恩近似理论,提出了衡量干涉程度的1П态双原子分子中关于Λ量子干涉的微分干涉角.利用各向异性相互作用势计算了其干涉角.得到分子束实验中微分干涉角随实验参数,包括实验温度、碰撞伴、作用距离和转动量子数变化的关系.并且讨论了影响干涉角的各种参数.此理论模型对理解和进行分子束实验是非常重要的.  相似文献   

6.
阐述了成像技术发展的3个阶段:机械电子化、自动化、数字成像阶段.具体包括胶片式向磁记录式的转变,胶片式与数字式的兼容,数字式的空间、辐射、光谱和时间分辨率成像的前沿技术.提出由部件到系统的成像自动处理控制理论,并阐述了未来成像技术的发展趋势.  相似文献   

7.
转动传能中的量子干涉: 干涉角和相对速度的关系   总被引:1,自引:0,他引:1  
考虑一级含时波恩近似和长程相互作用势, Sun提出了转动传能中的量子干涉模型.在静态池中CO A1Π~ e 3Σ-和He碰撞的实验已经成功模拟.为了从实验中直接获得碰撞速度和干涉角的关系, Sha提出了利用分子束和离子速度成像技术的实验.作为理论研究干涉角和碰撞速度的关系,计算了不同速度下的干涉角,同时获得了变化的趋势.对在分子束条件下(通过控制碰撞速度来控制干涉角)实验具有指导意义.  相似文献   

8.
现有的光学超分辨显微成像技术主要依赖于特殊的荧光标记物,其对于大多数非荧光样品的超分辨成像就变得无能为力。因此我们提出将光学相减显微技术应用到非荧光样品的成像当中,利用普通共聚焦光斑和面包圈型光斑分别激发样品的散射光成像,从而得到样品同一区域的两幅图像,再通过图像相减的方法提高了图像空间分辨率。不同于一般的超分辨成像方法,这种光学相减显微镜不需要特殊的样品预处理过程,同时两次成像的激发光强度可以保持在一个较低水平,避免了样品损伤的影响。随后金纳米小球和有机聚合物微丝的散射成像实验证明了光学相减显微镜可以将空间分辨率提高到215 nm (0.33λ, 1λ = 650 nm),并且通过探测散射信号得到更多的样品细节信息。  相似文献   

9.
提出了一种改进的阿达玛变换(HT)显微荧光图像分析系统,以单细胞试样分析为基础,分别对系统的分辨率和解码后的图像恢复过程进行了讨论.结果表明,该系统可应用于单细胞形态分析和定量分析.图像在x和y方向的像素分辨率相同,并达到了同一成像物镜下的空间分辨率水平,因此在获取微米级单细胞试样的微弱荧光信号的二维图像时,系统的成像能力较好,可用于单细胞形态分析.对花粉细胞的荧光衰退过程的定量分析结果表明,对不同HT图像提供的同一系列试样的定量数据进行比较时,必须对所有该系列试样的图像恢复过程进行归一化处理.  相似文献   

10.
报道了一种小动物活体荧光-光热双模成像系统, 其兼具荧光成像和热成像双功能, 具有成像灵敏度高、 采集速度快(≤51 frame/s)、 组织穿透深度大(近红外荧光成像时可达10 mm)以及0.1 ℃的热成像分辨率. 该系统不但能够实现小动物皮下肿瘤和深层组织/器官的荧光成像, 同时集成了热成像, 可实时监测光热治疗中的温度变化以及药物的控制释放过程, 有助于实现精准治疗.  相似文献   

11.
The response mechanism of a vertical alignment mode, driven by a fringe field, is investigated in detail using small-angle approximation. The flow effects can be ignored when using theoretical analysis. The period of the liquid crystal (LC) deformation in the transversal direction, instead of the lognitudinal direction, shows the cell gap effect on the response time in the LC layer's thickness. The authors' analytical results indicate that a liquid crystal display (LCD) mode with a small transversal period could provide a new method that gives a fast response.  相似文献   

12.
The isotope effect on the vibronic spectrum of naphthalene has been investigated under conditions of high resolution, enabling the resolution of individual vibronic states. Comparing the isotope effect for fixed vibronic states leads to an unexpected smoothing which is taken as evidence for a triplet communicating system, even though the singlet state is clearly not communicating.  相似文献   

13.
A mechanical device (NMR lift) has been built to displace vertically an object (typically an NMR sample tube) inside the NMR probe with an accuracy of 1 microm. A series of single pulse experiments are performed for incremented vertical positions of the sample. With a sufficiently spatially selective radio-frequency (r.f.) field, one obtains chemical shift information along the displacement direction (one-dimensional chemical shift imaging (CSI)). Knowing the vertical r.f. field profile (the amplitude of the r.f. field along the vertical direction), one can reconstruct the spectrum associated with all the slices corresponding to consecutive sample positions and improve the spatial resolution, which is simply related to the accuracy of the displacement device. Beside tests performed on phantoms, the method has been applied to solvent penetration in polymers and to benzene diffusion in a heterogeneous zeolite medium.  相似文献   

14.
Summary In this paper we investigate the potential of alkyl-bonded silica monolithic columns for the isolation and identification of drug-related components in biological fluids. Up to 6 columns have been connected in series to produce a chromatographic system with up to 40,000 plates. This high-resolution chromatography system has been coupled to both MS and NMR to enable efficient detection and characterisation of drug-related components in biological fluids. The use of six coupled columns has been shown to give enhanced resolution over a high quality silica particulate column packed with 3 μm material which exhibits the same back pressure. The effect of volume and mass load on the performance of monolithic columns for semi-preparative chromatography of biological fluids has also been investigated. In these studies it was possible to inject up to 100 mL of neat urine with no loss of chromatographic performance. Furthermore, upon re-testing, the columns showed similar chromatographic performance. Again several columns were serially connected, producing enhanced resolution in the semi-preparative mode.  相似文献   

15.
In electron dynamics calculations the interatomic Coulombic decay (ICD) process has recently been shown to take place in two vertically‐aligned quantum dots (QDs). Energy emitted during the relaxation of one electron in one QD is converted into kinetic energy of another electron ejected from a neighboring QD. As the electronic structure of QDs can be controlled by their geometries, we prove here in thorough scans of the transversal and vertical QD confinement potentials’ widths that geometries are likewise control parameters for ICD. Such a comprehensive investigation has been enabled by a significant development of the calculations in terms of speed achieved among others by optimization of the grid and Coulomb interaction operator representations. As key result of this study we propose two cigar‐shaped singly‐charged GaAs QDs vertically aligned in the direction of their long side for a most efficient QD ICD realization useful for an infrared photodetector. © 2016 Wiley Periodicals, Inc.  相似文献   

16.
The enantiomeric resolution of (+/-)-ibuprofen into its enantiomers was achieved by TLC on silica gel plate using optically pure (-)-brucine as a chiral selector and acetonitrile-methanol (5:1, v/v) as the solvent system. Spots were located in an iodine chamber. The detection limit was 4.9 microg. The effect of concentration of the chiral selector, temperature and pH on resolution has been studied.  相似文献   

17.
With the aid of an improved wave function that exactly describes the motion of an electron in parallel uniformē andB fields and by using a modified statistical operator, the reaction of the uncoupled electron-phonon system to the perturbing electron-phonon interaction is expressed according to the linear response theory. As in the transversal case the final result contains only observables and is free from any adjustable parameters. For strong magnetic fields a closed expression for the final result is obtained. The magnetic effect on the change of resistance is more dominant in the transversal case than in the longitudinal case. A comparison with experiment is made for Cd at 78 °K in the range 200~300 kG and agrees reasonably well.  相似文献   

18.
Kim DJ  Oh HJ  Park TH  Choo JB  Lee SH 《The Analyst》2005,130(3):293-298
The focus of this paper is on the fabrication of a PDMS-based passive efficient micromixer to be easily integrated into the other on-chip microfluidic system. The mixing is achieved by "strong stretching and folding," which employs a three-dimensional microchannel structure. By the simultaneously vertical and transversal dispersion of fluids, strong advection is developed. Owing to this powerful mixing performance (more than 70% of the mixing is accomplished within 2.3 mm over a wide range of Reynold number (Re)), the smaller integrative mixer can be realized. The feasibility and the potential usefulness of an integrative micromixer were evaluated by incorporating two mixers into the microchannel for the spectroscopic detection of a glucose-catalyst reaction. The results demonstrate a promising performance for diverse applications in the assay or synthesis of biological or chemical materials.  相似文献   

19.
Zhan X  Desiderio DM 《Electrophoresis》2003,24(11):1834-1846
Two-dimensional polyacrylamide gel electrophoresis (PAGE), together with 2-D gel electrophoresis (GE) analysis software, is a common technique to analyze a complex proteome. In order to accurately locate the differentially expressed proteins in human pituitary macroadenoma tissues in our long-term research program to clarify the molecular mechanisms of macroadenoma formation, a reproducible separation system is needed. An immobilized pH-gradient dry gel-strip (IPG strip) has been extensively used for first-dimensional isoelectric focusing (IEF), and has achieved a high degree of reproducibility in the IEF direction. For the second dimension (SDS-PAGE), different types of gel systems are available, including horizontal vs. vertical gel systems, and gradient vs. constant-percentage gels. A typical horizontal system is the Multiphor II system that analyzes one gel at a time, using a precast gradient gel (180 x 245 x 0.5 mm), and a typical vertical system is the Dodeca system, which analyzes up to 12 gels at a time, using usually a single-concentration gel (190 x 205 x 1 mm). The present study evaluated the spatial and quantitative reproducibility of the two systems for the separation of the complex human pituitary proteome. PDQuest software was used to analyze the digitized gel-image data, and SPSS statistical software was used to analyze the data. The results demonstrated a high percentage (>99%) of protein-spot matches within each electrophoretic system. The Dodeca gel system demonstrated better between-gel reproducibility for spot position, higher resolution in the Sodium dodecyl sulfate (SDS)-PAGE direction, lower gel background, better spot quality, and higher reproducibility of the spot volume.  相似文献   

20.
Chen Z  Burns MA 《Electrophoresis》2005,26(24):4718-4728
An adequate buffer reservoir is one essential component of an electrophoresis system, providing current carrying ions and maintaining constant pH. In a microfabricated DNA separation system with on-chip electrodes, the amount of buffer used is limited by the design of the device; the buffer continuity can be easily disturbed by the production of bubbles. Continuously flowing 1 x Tris-borate-EDTA (TBE) buffer over the electrodes at the cathodic end solves both problems. This flow increases the resolution for ssDNA primer separations (21 and 25 bases) to a maximum value of 1.4 within a distance of 1.2 cm, about four times higher than that without flow. Similar improvement has been achieved for dsDNA separation (20 bp ladder; BioRad) at a distance of only 0.4 cm, giving baseline resolution for bands from 20 to 240 bp. We have also investigated the effect of buffer concentration on resolution, and no similar improvement can be obtained by merely increasing the buffer concentration without flow.  相似文献   

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