游离细胞的扫描电镜样品制备

游离细胞的扫描电镜样品制备金立强（南京铁道医学院电镜室，南京２１０００９）如何收集悬液中的游离细胞，使之在样品载物台上单层平铺，并且在一系列处理过程中不发生变形和脱落，是扫描电镜制样方法中值得探讨的课题。笔者经反复试验，摸索出较简便实用的琼脂膜载物片...     

血细胞扫描电镜样品制备方法的探索

血细胞扫描电镜样品制备方法的探索侯燕平牛吉山杨煜升（山西农业大学电镜室，山西太谷０３０８０１）在扫描电镜生物样品中，经常遇到象单细胞等含水份较多的材料。样品的干燥是扫描电镜制样的关键环节，而传统的临界点干燥法过程繁杂，并且需要配备高压的液态二氧化碳，...     

放线菌扫描电镜样品制备方法比较研究

目的:比较和筛选放线菌扫描电镜样品制备方法。方法:通过培养获得插片、菌饼和发酵液3种待处理样品,根据单因素试验设计原则采用双固定、单固定、磷酸缓冲液清洗、生理盐水清洗、蒸馏水清洗、丙酮脱水、乙醇脱水和直接表面镀金等8种方法对样品进行处理。结果:取样时间直接影响观察样品形态的丰富度;插片样品扫描获得的结果较为理想;不同的固定、清洗和脱水等处理过程也对样品的细节产生了影响。结论:插片样品直接干燥喷金扫描观察是一种简便、快速的方法,对于常规的放线菌观察与鉴定较为实用,也为其它微生物扫描电镜观察提供了参考。     

微波辐射扫描电镜生物样品制备方法

近几年来,微波辐射(MW)被成功地引入光镜、电镜和免疫组织化学等生物样品制备和研究,受到国内外电镜工作者的关注。本文将MW引入扫描电镜生物样品制备的各个过程,进行了一系列对比实验,旨在获得MW扫描电镜生物样品制备的适宜条件和方法。实验材料为交链孢子(Alternaria Sp.)和小白鼠气管。使用广东蚬华产家用微波炉。工作频率2450MHz,最大输出功率700W,10档可调。在炉内中央放置一个直径10厘米玻璃培养器,内装200毫升水。将装有2毫升浸泡液和试样的青霉素小瓶放在培养器中,温度探测棒浸入水中监测水温。功率输出选第一档(370W),进行定     

扫描电镜样品制备的优化

本文总结了在扫描电镜分析检测中,电镜样品的制备、实验观测和仪器维护等经验.针对扫描电镜观测样品进行了分类,并详细介绍了不同样品的制备方法及需要注意的事项,为获取高质量的电镜图像提供必要的保障.     

扫描电镜鱼类染色体样品制备技术

本文应用导电染色技术对鱼类染色体样品制备进行了探索。结果表明:以该方法制备的样品在扫描电镜观察中能清晰地显示出鱼类染色体的精细结构。     

一种快速简便的扫描电镜样品制备法

一种快速简便的扫描电镜样品制备法李向党（西安第四军医大学电镜室，西安７１００３２）为了研究生物样品凹凸不平的立体结构，通常需要使用扫描电镜的样品制备技术，常规扫描电镜的样品制备技术所需时间长，操作复杂，仪器昂贵，基层单位无法承受。我们现采用六甲基二硅...     

扫描电镜细胞样品制备方法的改进

扫描电镜已广泛用于对细胞表面结构的观察，但在细胞样品制备过程中，往往因脱水或干燥引起细胞体积或表面结构的改变，导致观察结果出现误差或失真。为了避免这类问题，我们以鱼类培养细胞为材料，对其扫描电镜样品制备技术进行了一些改进，举例如下。     

兰花蕉花粉的扫描电镜样品制备技术

兰花蕉花粉的扫描电镜样品制备技术＊徐信兰卢乃弟王学海（中国科学院华南植物研究所电镜室，广州５１０６５０）＊中国科学院广州分院分析测试基金资助项目兰花蕉科植物的花粉壁结构比较特殊，它的外壁很薄且不完整甚至外壁缺失，因此用常规的花粉扫描电镜样品制备方法（...     

扫描电镜花粉制备方法

采用制备光镜花粉标本所常用的醋酸酐－硫酸分解法来处理扫描电镜花粉标本，处理后的花粉经清洗、脱水、临界干燥。此法处理的花粉形状不变，且外壁雕纹清晰，可得到良好的花粉外壁剖面结构图。     

Exact 3D simulation of Scanning Electron Microscopy images of semiconductor devices in the presence of electric and magnetic fields

Simulations of Scanning Electron Microscopy images of semiconductor devices in the presence of electric fields are usually too simplistic, since they just rely on approximated solutions of the Poisson equation. In this paper, the 3D Poisson equation is solved in a TCAD environment, which accounts for realistic boundary conditions, as well as for complex physical effects like the formation of space charge regions in semiconductors and the polarization of dielectrics. The calculated solution is then passed to a Monte Carlo code that implements a new electron tracking engine optimized for speed, stability, and accuracy. After introducing the new tracking engine, three simulation examples are presented dealing with the presence of an extraction field, self-charging of the irradiated sample, and potential contrast in a biased silicon junction.     

肠道杆菌的扫描电镜观察

我们用扫描电镜观察肠道杆菌种(Enterobacteriaceae)中的四种细菌,大肠埃希氏杆菌(Escherichiacoli),普通变形杆菌(Proteus vulgaris),伤寒沙门氏菌(Salmonella typhi)和福氏志贺氏菌(Shigella Flexneri)。未处理的菌落标本,菌落表面都可形成一层厚薄不同的表膜(Surface film)。四种细菌菌落的表膜,形状不一,千姿百态。适当处理后的菌落标本,则可显示菌体的本来面目。四种细菌菌体在菌落表面的分布和排列,也是各不相同,千差万别。本文根据扫描电镜的观察,对四种不同菌落进行了讨论。     

一种观察细胞骨架的简易整装电镜制样方法

本文介绍一种显示细胞骨架的简易有效的整装电镜制样方法。24孔培养板上钻以直径为2.5mm的圆孔,覆上0.25%的Formvar膜后,成为培养细胞的良好支撑物,然后在原位对培养的细胞进行抽提、固定和二氧化碳临界点干燥,相差显微镜下观察、选择和定位,再以浸湿的单目铜网置于圆孔上,自然干燥后取上已覆有Formvar膜的铜网,即可进行标本的观察。该方法材料来源容易、经济,操作简便,成功率较高,并可减少盲目的电镜观察及人工假象,所得的细胞骨架图像清晰。     

用弹道电子发射显微术研究超薄金属硅化物/硅肖特基接触

采用弹道电子发射显微术 ( BEEM)技术对超薄 Pt Si/Si、Co Si2 /Si肖特基接触特性进行了研究 ,并与电流 -电压 ( I- V)及电容 -电压 ( C- V)测试结果进行了对比 .研究了 Ar离子轰击对超薄Pt Si/n- Si肖特基接触特性的影响 .BEEM、I- V/C- V技术对多种样品的研究结果表明 ,I- V/C- V测试会由于超薄硅化物层串联电阻的影响而使测试结果产生严重误差 ;BEEM测试则不受影响 .随着离子轰击能量增大 ,肖特基势垒高度降低 ,且其不均匀性也越大 .用 BEEM和变温 I- V对超薄 Co Si2 /n- Si肖特基二极管的研究结果表明 ,变温 I- V测试可在一定程度上获得肖特基势垒     

Conventional Electron Microscopy and Electron Holography of Organic Solar Cells

Organic solar cells are a promising route towards large‐area and low‐price photovoltaic systems. The devices are composed of at least two layers: the hole‐transport layer and the electron‐transport layer. The light absorption can occur in one or both layers. At the interface of the layers the excitons are separated into charge carriers, and every layer deals with one type of carrier. Higher efficiencies of the separation process can be obtained by using a mixed layer containing both materials to obtain a very high interface area. Although the structure of the mixed layers used plays a crucial role for the device performance, until now the morphologies have not been elucidated. In order to correlate physical and optical findings with structure and morphology for the materials in question, electron microscopy experiments were performed on the single components as well as on the layer systems. The conventional electron microscope is a poor phase microscope. As consequence, weak‐phase objects like organic molecules have to be stained or imaged under strong defocus to produce an observable contrast. Artifacts caused by chemical staining and the appearance of Fresnel diffraction using the defocus technique represent the main problems of conventional microscopy. These artifacts can be avoided using electron holography. Holograms of ultrathin sections of thin layers composed of organic dye molecules were recorded. Subsequently, the phase images were reconstructed. In this manner, we succeeded in obtaining high‐contrast electron micrographs without applying staining or defocus. In addition, holograms of crystalline C₆₀ and zinc phthalocyanine were successfully recorded. Holography has been shown to be a useful tool to image beam‐sensitive and weak‐phase objects without artifacts.     

Characterization of Geoinspired and Synthetic Chrysotile Nanotubes by Atomic Force Microscopy and Transmission Electron Microscopy

Geoinspired synthetic chrysotile nanotubes both stoichiometric and 0.67 wt % Fe doped were characterized by transmission electron microscopy and electron diffraction. Bending tests of the synthetic chrysotile nanotubes were performed using the atomic force microscope. The nanotubes were found to exhibit elastic behaviour at small deformations (below ca. 20 nm). Young's modulus values of (159 ± 125) GPa and (279 ± 260) GPa were obtained from the force‐deflection curves using the bending equation for a clamped beam under a concentrated load, for the stoichiometric and the Fe doped chrysotile nanotubes, respectively. The structural modifications induced by Fe doping altered the mechanical properties, with an apparent dependence of the latter on the number of constituting walls of the nanotubes.     

原生动物扫描电镜样品制备方法的探讨

以腹毛目纤毛虫棘尾虫、尖毛虫和游仆虫,膜口目纤毛虫草履虫以及腰鞭目鞭毛目角藻为材料,对原生动物扫描电镜样品制备方法作了探讨,提出了样品制备过程中取材固定、脱水、干燥后原生动物在样品台上的定位等值得注意的问题,取得成功的关键及一些体会。     

Scanning Kelvin Probe Microscopy on Bulk Heterojunction Polymer Blends

Here, correlated AFM and scanning Kelvin probe microscopy measurements with sub‐100 nm resolution on the phase‐separated active layer of polymer‐fullerene (MDMO‐PPV:PCBM) bulk heterojunction solar cells in the dark and under illumination are described. Using numerical modeling a fully quantitative explanation for the contrast and shifts of the surface potential in dark and light is provided. Under illumination an excess of photogenerated electrons is present in both the donor and acceptor phases. From the time evolution of the surface potential after switching off the light the contributions of free and trapped electrons can be identified. Based on these measurements the relative 3D energy level shifts of the sample are calculated. Moreover, by comparing devices with fine and coarse phase separation, it is found that the inferior performance of the latter devices is, at least partially, due to poor electron transport.     

Photoemission Electron Microscopy of TiO2 Anatase Films Embedded with Rutile Nanocrystals

Photoemission electron microscopy (PEEM) excited by X‐ray and UV sources is used to investigate epitaxial anatase thin films with embedded rutile nanocrystals, a model system for the study of heterocatalysis on mixed‐phase TiO₂. Both excitation sources show distinct contrast between the two TiO₂ phases; however, the contrast is reversed. Rutile nanocrystals appear darker than the anatase film in X‐ray PEEM images but brighter in UV‐PEEM images. We observe that topography‐induced contrast is dominant in X‐ray PEEM imaging, whereas work function and density‐of‐state‐based contrast, dominates in UV‐PEEM. This assertion is confirmed by UPS and conducting AFM data that shows the rutile work function to be 0.2 eV lower and a greater occupied valence band density‐of‐states in rutile (100) than in anatase (001). Since the boundaries between rutile nanocrystals and the anatase film are clearly resolved, these results indicate that PEEM studies of excited state dynamics and heterocatalysis are possible at chemically intriguing mixed‐phase TiO₂ interfaces and grain boundaries.