Name: light-induced in situ transmission electron microscopy for observation of the liquid-soft matter interaction
Uploaded: 2022-07-26T13:30:00
Description: Watch this Scientific Journal Video about Light-Induced In Situ Transmission Electron Microscopy for Observation of the Liquid-Soft Matter Interaction at JoVE.com

该研究得到了微型基金（2019/03/X/NZ3/02100，波兰国家科学中心）的支持。

1.透射电子显微镜改性
<ol><li>通过将光纤（见 材料表）连接到物镜顶部的显微镜柱来修改透射电子显微镜。物镜和聚光镜之间留出几厘米的空间，外加一个用于存放配件的空闲插槽。 注意：也可以使用专用样品架4 或反向配置1 的阴极发光观察支架。</li>
	<li>使用粗真空泵检查系统是否有泄漏。如果系统没有显示真空泄漏，请在高真...

<ol>
	<li>Vadai, M., Angell, D. K., Hayee, F., Sytwu, K., Dionne, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In-situ+observation+of+plasmon-controlled+photocatalytic+dehydrogenation+of+individual+palladium+nanoparticles.">In-situ observation of plasmon-controlled photocatalytic dehydrogenation of individual palladium nanoparticles.</a> Nature Communications. 9 (1), 1-8 (2018).</li><li>Weng, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visualizing+light-induced+dynamic+structural+transformations+of+Au+clusters-based+photocatalyst+via+in+situ+TEM.">Visualizing light-induced dynamic structural transformations of Au clusters-based photocatalyst via in situ TEM.</a> Nano Research. 12 (1), 1-5 (2021).</li><li>Cao, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+TEM+investigation+on+ultrafast+reversible+lithiation+and+delithiation+cycling+of+Sn@C+yolk-shell+nanoparticles+as+anodes+for+lithium+ion+batteries.">In situ TEM investigation on ultrafast reversible lithiation and delithiation cycling of Sn@C yolk-shell nanoparticles as anodes for lithium ion batteries.</a> Nano Energy. 40, 187-194 (2017).</li><li>Cavalca, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+transmission+electron+microscopy+of+light-induced+photocatalytic+reactions.">In situ transmission electron microscopy of light-induced photocatalytic reactions.</a> Nanotechnology. 23 (7), 075705 (2012).</li><li>Tung, C. -. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Light-induced+activation+of+adaptive+junction+for+efficient+solar-driven+oxygen+evolution:+In+situ+unraveling+the+interfacial+metal-silicon+junction.">Light-induced activation of adaptive junction for efficient solar-driven oxygen evolution: In situ unraveling the interfacial metal-silicon junction.</a> Advanced Energy Materials. 9 (31), 1901308 (2019).</li><li>&#379;ak, A. M., Kaczmarczyk, O., Piksa, M., Matczyszyn, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Light-induced+in+situ+transmission+electron+microscopy:+Novel+approach+for+antimicrobial+photodynamic+therapy+imaging.">Light-induced in situ transmission electron microscopy: Novel approach for antimicrobial photodynamic therapy imaging.</a> Photodiagnosis and Photodynamic Therapy. 35, 102463 (2021).</li><li>Shindo, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+a+multifunctional+TEM+specimen+holder+equipped+with+a+piezodriving+probe+and+a+laser+irradiation+port.">Development of a multifunctional TEM specimen holder equipped with a piezodriving probe and a laser irradiation port.</a> Journal of Electron Microscopy. 58 (4), 245-249 (2009).</li><li>Zhang, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photosensing+performance+of+branched+CdS/ZnO+heterostructures+as+revealed+by+in+situ+TEM+and+photodetector+tests.">Photosensing performance of branched CdS/ZnO heterostructures as revealed by in situ TEM and photodetector tests.</a> Nanoscale. 6 (14), 8084-8090 (2014).</li><li>Zhang, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Statistically+analyzed+photoresponse+of+elastically+bent+CdS+nanowires+probed+by+light-compatible+in+situ+high-resolution+TEM.">Statistically analyzed photoresponse of elastically bent CdS nanowires probed by light-compatible in situ high-resolution TEM.</a> Nano Letters. 16 (10), 6008-6013 (2016).</li><li>Yoshida, K., Yamasaki, J., Tanaka, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+high-resolution+transmission+electron+microscopy+observation+of+photodecomposition+process+of+poly-hydrocarbons+on+catalytic+TiO2+films.">In situ high-resolution transmission electron microscopy observation of photodecomposition process of poly-hydrocarbons on catalytic TiO2 films.</a> Applied Physics Letters. 84 (14), 2542-2544 (2004).</li><li>Yoshida, K., Nozaki, T., Hirayama, T., Tanaka, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+high-resolution+transmission+electron+microscopy+of+photocatalytic+reactions+by+excited+electrons+in+ionic+liquid.">In situ high-resolution transmission electron microscopy of photocatalytic reactions by excited electrons in ionic liquid.</a> Journal of Electron Microscopy. 56 (5), 177-180 (2007).</li><li>Textor, M., De Jonge, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Strategies+for+preparing+graphene+liquid+cells+for+transmission+electron+microscopy.">Strategies for preparing graphene liquid cells for transmission electron microscopy.</a> Nano Letters. 18 (6), 3313-3321 (2018).</li><li>Ring, E. 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M., Damiano, J., Timp, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gene+expression+in+electron-beam-irradiated+bacteria+in+reply+to+&amp;#34;live+cell+electron+microscopy+is+probably+impossible.&amp;#34.">Gene expression in electron-beam-irradiated bacteria in reply to &amp;#34;live cell electron microscopy is probably impossible.&amp;#34.</a> ACS Nano. 11 (1), 3-7 (2017).</li><li>Alves, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+insight+on+bacterial+cellular+targets+of+photodynamic+inactivation.">An insight on bacterial cellular targets of photodynamic inactivation.</a> Future Medicinal Chemistry. 6 (2), 141-164 (2014).</li><li>Cieplik, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antimicrobial+photodynamic+therapy-What+we+know+and+what+we+don't.">Antimicrobial photodynamic therapy-What we know and what we don't.</a> Critical Reviews in Microbiology. 44 (5), 571-589 (2018).</li><li>Huang, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Type+I+and+Type+II+mechanisms+of+antimicrobial+photodynamic+therapy:+An+in+vitro+study+on+gram-negative+and+gram-positive+bacteria.">Type I and Type II mechanisms of antimicrobial photodynamic therapy: An in vitro study on gram-negative and gram-positive bacteria.</a> Lasers in Surgery and Medicine. 44 (6), 490-499 (2012).</li><li>Caminos, D. A., Spesia, M. B., Pons, P., Durantini, E. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanisms+of+Escherichia+coli+photodynamic+inactivation+by+an+amphiphilic+tricationic+porphyrin+and+5,10,15,20-tetra(4-N,N,N-trimethylammoniumphenyl)+porphyrin.">Mechanisms of Escherichia coli photodynamic inactivation by an amphiphilic tricationic porphyrin and 5,10,15,20-tetra(4-N,N,N-trimethylammoniumphenyl) porphyrin.</a> Photochemical and Photobiological Sciences. 7 (9), 1071-1078 (2008).</li><li>Chu, J. C. H., Chin, M. L., Wong, C. T. T., Hui, M., Lo, P. C., Ng, D. K. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=One-pot+synthesis+of+a+cyclic+antimicrobial+peptide-conjugated+phthalocyanine+for+synergistic+chemo-photodynamic+killing+of+multidrug-resistant+bacteria.">One-pot synthesis of a cyclic antimicrobial peptide-conjugated phthalocyanine for synergistic chemo-photodynamic killing of multidrug-resistant bacteria.</a> Advanced Therapeutics. 4 (3), 1-10 (2021).</li><li>Rogers, S., Honma, K., Mang, T. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Confocal+fluorescence+imaging+to+evaluate+the+effect+of+antimicrobial+photodynamic+therapy+depth+on+P.+gingivalis+and+T.+denticola+biofilms.">Confocal fluorescence imaging to evaluate the effect of antimicrobial photodynamic therapy depth on P. gingivalis and T. denticola biofilms.</a> Photodiagnosis and Photodynamic Therapy. 23, 18-24 (2018).</li><li>Maldonado-Carmona, N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Porphyrin-loaded+lignin+nanoparticles+against+bacteria:+A+photodynamic+antimicrobial+chemotherapy+application.">Porphyrin-loaded lignin nanoparticles against bacteria: A photodynamic antimicrobial chemotherapy application.</a> Frontiers in Microbiology. 11, 606185 (2020).</li><li>&#379;ak, A. M., Kaczmarczyk, O., Piksa, M., Grz&#281;da, J., Matczyszyn, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fiber-optic+sample+illuminator+design+for+the+observation+of+light+induced+phenomena+with+transmission+electron+microscopy+in+situ:+Antimicrobial+photodynamic+therapy.">Fiber-optic sample illuminator design for the observation of light induced phenomena with transmission electron microscopy in situ: Antimicrobial photodynamic therapy.</a> Ultramicroscopy. 230, 113388 (2021).</li><li>Dinh, V. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insight+into+the+adsorption+mechanisms+of+methylene+blue+and+chromium(III)+from+aqueous+solution+onto+pomelo+fruit+peel.">Insight into the adsorption mechanisms of methylene blue and chromium(III) from aqueous solution onto pomelo fruit peel.</a> RSC Advances. 9 (44), 25847-25860 (2019).</li><li>&#379;ak, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Guide+to+controlling+the+electron+dose+to+improve+low-dose+imaging+of+sensitive+samples.">Guide to controlling the electron dose to improve low-dose imaging of sensitive samples.</a> Micron. 145, 103058 (2021).</li><li>Drulyte, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Approaches+to+altering+particle+distributions+in+cryo-electron+microscopy+sample+preparation.">Approaches to altering particle distributions in cryo-electron microscopy sample preparation.</a> Acta Crystallographica Section D. 74 (6), 560-571 (2018).</li><li>Scarff, C. 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照明器的安装和调试需要基本的维修知识，并且可能会损坏显微镜。将光线引入显微镜的最简单方法是从物镜顶部连接光纤，那里通常有空间容纳TEM偏转线圈和额外的探测器。较旧的顶部入口设备也可以获得更多可用空间，其中相同的位置容纳样品真空锁和样品安装机构。这种配置在先前的报告25中被广泛描述，该报告25包含示例性照明器设计。如果显微镜内部不允许将光纤安装...

高分辨率的光诱导现象在许多领域都很有趣，例如纳米工程1，2，3，催化4，5和生物光子学6。可以在文献中找到一些允许这种实验的原始设计，包括样品架1，4，7，8，9和连接到显微镜10，11的光纤的修改。
光照明、液体环境和透射电子显微镜（TEM）的结合为光诱导过程的详细动态研究提供了很好的机会。然而，显微镜内部的高真空条件对许多液体相当不利，尤其是水溶液。液体封装可以保护其免受环境的影响，可以使用一些主要基于石墨烯12，氮化硅13或碳14 基底的技术来实现。除了材料科学研究2外，所谓的液体细胞还提供了对生物标本在其天然条件附近进行非常规显微镜观察的可能性15。这样的观察要求非常高，特别是对于细菌细胞等活微生物。电子束作为电离辐射对水合标本造成不可逆的损伤，因此必须指定电子剂量16。这对于最大程度地减少不利影响、控制损坏和避免混淆伪影是必要的。允许观察活细胞的最佳最大电子剂量仍然是一个有问题的话题16，但30 e− / nm 2 的剂量似乎是阈值，至少对于细菌17。
此类显微镜研究感兴趣的一些主题是抗菌光动力治疗（APDT）期间的过程18。简而言之，治疗进行如下。细菌细胞被称为光敏剂的光敏液体包围。当以特定波长进行光照明时，细胞毒性活性氧（ROS）是由激发的光敏剂分子的能量或电荷转移到溶液中天然存在的氧气产生的。暴露于ROS的病原体以非常高的效率快速灭活，没有副作用19。对于不同的微生物，对治疗的反应各不相同 - 例如，对于革兰氏阳性和革兰氏阴性细菌20，同一光敏剂的影响可能完全不同。一般来说，已经确定ROS的主要目标是细胞的外部结构，其中损伤导致细胞膜的功能紊乱，从而导致细菌死亡21，22。然而，对核酸和蛋白质扫描的损伤也被认为是失活的原因18，因此在此过程中哪些细胞结构是主要靶标仍然未知19。更深入地了解破坏性过程可能有助于改善这种确定性疗法。与APDT研究中使用的光学显微镜方法23相比，TEM技术为以更高的分辨率和放大倍率观察APDT机制提供了更多的可能性24。TEM已经成功地用于正在进行的治疗期间的细胞观察，这使我们能够研究革兰氏阳性细菌损伤并详细描述细胞壁内发生的变化6，25。
目前的协议为使用TEM对光诱导细菌灭活的高分辨率成像提供了一种合适的实验设置，这需要适当的光照明系统，用液体封装细胞以及严格的电子剂量控制。用于观察的细菌是 金黄色葡萄球菌，并使用亚甲蓝溶液作为光敏剂。特殊的光照明设置包括使用光光纤直接连接到显微镜柱的可调谐半导体激光器。由于光纤几乎平行于显微镜轴线，因此这种设计在整个样品中提供了均匀的照射。然后，激光产生的高强度单色光可用于研究各种光化学效应。实验中使用的光的波长等于660nm，因为在可见光区域，亚甲蓝在613nm和664nm处具有吸收峰26。液体封装方案基于碳基质，这使得该过程快速而简单。最后，提出了一种对液体中细胞进行低 剂量原位 TEM观察的方法。讨论了样品制备的难点、电子剂量对敏感样品的影响以及合理的图像解释。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Carbon film on 200 mesh copper grid</td>
			<td>Agar Scientific</td>
			<td>AGS160</td>
			<td>The standard TEM grids for observations and liquid cell preparation</td>
		</tr>
		<tr>
			<td>Crossover Tweezers</td>
			<td>Dumont</td>
			<td>N5</td>
			<td>The tweezers are neecesarry for liquid cell preparation</td>
		</tr>
		<tr>
			<td>Photodiode Power Sensor</td>
			<td>ThorLabs</td>
			<td>S130C</td>
			<td>The sensor used for light intensity measurement</td>
		</tr>
		<tr>
			<td>Polyimide-Coated Multimode Fiber</td>
			<td>Thorlabs</td>
			<td>FG400UEP</td>
			<td>Must be built into the microscope using the on-site built adapter, according to the 10.1016/j.ultramic.2021.113388</td>
		</tr>
		<tr>
			<td>Transmission Electron Microscope</td>
			<td>Hitachi</td>
			<td>H-800</td>
			<td>Can be replaced with any side-entry microscope, available for modification</td>
		</tr>
		<tr>
			<td>Tuneable Diode Laser</td>
			<td>CNI</td>
			<td>MRL-III-660D</td>
			<td>The light wavelength must be chosen basing on photosensitizer&#39;s absorption spectrum</td>
		</tr>
	</tbody>
</table>

light-induced in situ transmission electron microscopy for observation of the liquid-soft matter interaction

当前协议描述了用于 原位 光诱导观察的透射电子显微镜（TEM）设置的修改。将玻璃光纤插入物镜极片上方的电子柱中，并使用可调节光源激光器来制造该装置。使用外部测量系统校准照明器后，它允许人们根据观察过程的需要调整照明强度。该照明系统用于对抗菌光动力治疗现象进行成像，这是目前深入研究的主题。通过在碳、石墨烯或氮化硅衬底上点样细菌悬浮液，印迹过量溶液，点样光敏剂溶液，再次吸干过量液体，然后用第二种底物或石墨烯膜组装液池来制备样品。成像实验本身的过程包括使用低放大倍率和最小剂量的电子选择合适的观察地点，然后周期性激活光源，以指定的间隔以最少的电子量捕获后续图像。由于观察到的现象的复杂性，需要仔细记录每次曝光的电子剂量以及使用的照明时间和强度，因为同时该过程既是光驱动的，也是电子驱动的。在进行实际实验后，必须进行额外的控制观察，其中使用相同剂量的电子但没有额外的光影响，并且较小剂量的电子用于更高剂量的光。这使得在生命和材料科学领域将光诱导的微观结构效应与电子引起的微结构效应区分开来成为可能。

该实验装置旨在以高分辨率观察液体中发生的光诱导过程。对图像的竞争分析使我们能够区分电子束造成的损伤与与光化学反应相关的变化。当电子均匀地穿透它时，电子束对敏感样品（在这种情况下，用液体包裹的细胞）的影响在整个照射区域都是可见的。当然，效果取决于电子剂量，因此对于更聚焦的光束，可以更快地观察到样品形态的更显着变化。与这种严重的损伤相比，光动力失活的实?...

Watch this Scientific Journal Video about Light-Induced In Situ Transmission Electron Microscopy for Observation of the Liquid-Soft Matter Interaction at JoVE.com

Light-Induced In Situ Transmission Electron Microscopy for Observation of the Liquid-Soft Matter Interaction

本协议描述了使用光照明系统进行透射电子显微镜（TEM）修饰，制造液体细胞以及细菌细胞和光敏剂之间光诱导相互作用的 原位 TEM观察。还讨论了样品制备方法、电子束损伤和成像。

光诱导 原 位透射电子显微镜观察液-软物质相互作用

The current protocol describes the modifications of the transmission electron microscope (TEM) setup for in situ light-induced observations. A glass ...

该协议介绍了如何使用液体细胞TEM和光照明的组合来观察光照明时用光敏剂封装的细菌的结构变化。这种技术的主要优点是它的简单性。该方案不需要困难的样品制备，并用光敏剂溶液提供足够的细菌包封。首先，通过将光纤连接到物镜顶部的显微镜柱来修改透射电子显微镜。物镜和聚光镜之间留出几厘米的空间，外加一个用于存放配件的空闲插槽。将两个覆盖有无定形碳的未经处理的TEM网格放在两个交叉的镊子之间，面向顶部的碳涂层面。使网格尽可能靠近边缘。将四微升细菌溶液放在其中一个网格上。样品的光密度必须在5到10的范围内。等待60秒，然后使用滤纸小心地吸干液体。在此过程中，尝试将液体散布在整个网格表面。将四微升光敏剂放在同一个网格上。五秒钟后，吸干液体。在基材上留下一层非常薄的液体。快速将干燥的网格放在覆盖有液体的网格顶部。轻轻地将上部网格移动到第二个网格的边缘，然后用镊子挤压边缘的基板。小心地重复挤压。将液体细胞放在镊子之间一分钟。完成制备后立即将样品插入TEM支架。将样品插入显微镜后，以低倍率模式开始观察，以找到合适的观察区域。在观察过程中，保持电子剂量尽可能低。延长曝光时间。在适当的放大倍率下找到被液体包围的细胞，并延长曝光时间，并立即捕获第一张图像。保持电子剂量恒定，每30秒收集一次图像以观察变化。仔细检查图像并计算对应于细胞中第一个可见变化的总电子剂量。在开始实验之前，通过调整电流值来设置激光强度。将样品插入显微镜并找到观察区域。在开始对样品进行照明之前捕获细胞的第一张图像，并使用光束遮蔽器关闭电子束以避免电子辐射的影响。打开激光。从较短的照明时间开始，因为激光具有相对较高的强度。之后，关闭光源。关闭光束遮光器，并立即捕获图像。如果可能，请使用自动算法仅在拍摄图像所需的时间内曝光样本。仔细测量电子照射时间以计算用于成像的电子剂量。观察到由一分钟后光敏剂的较轻辐射产生的活性氧引起的细胞外层显着降解。进一步的光照使变化更加明显。在低放大倍率下很容易找到具有足够液体的适当观察点，因为这些区域看起来更暗和模糊。液体覆盖的细菌比干燥的细菌更不明显，但仍然可以区分。在成像过程中观察液体边界很有用，并且可以轻松检测到其运动，这意味着所选区域可能不合适且不稳定。观察期间的另一个问题是水的蒸发和溶液的沉淀，这可能发生在样品的随机区域，包括细菌周围的区域。细菌的包封也可以使用石墨烯和硝酸硅膜进行。样品制备比较困难，但液室的稳定性会更好。所提出的方法可用于观察液体上的光诱导反应。例如，光对金属材料的影响，光诱导的催化剂和光化学反应。

Research

JoVE Journal

Engineering

Light-Induced In Situ Transmission Electron Microscopy for Observation of the Liquid-Soft Matter Interaction

Revealing Dynamic Processes of Materials in Liquids Using Liquid Cell Transmission Electron Microscopy

在液体中使用液体池透射电子显微镜揭示材料的动态过程

The recent development for in situ transmission electron microscopy, which allows imaging through liquids with high spatial resolution, has attracted ...

科研

工程学

In Situ Time-dependent Dielectric Breakdown in the Transmission Electron Microscope: A Possibility to Understand the Failure Mechanism in Microelectronic Devices

In Situ Time-dependent Dielectric Breakdown in the Transmission Electron Microscope: A Possibility to Understand the Failure Mechanism in Microelectronic Devices

在透射电子显微镜原位时间相关的介质击穿：一种可能性，了解微电子器件的失效机理

The time-dependent dielectric breakdown (TDDB) in on-chip interconnect stacks is one of the most critical failure mechanisms for microelectronic devices. ...

Studying Dynamic Processes of Nano-sized Objects in Liquid using Scanning Transmission Electron Microscopy

使用扫描透射电子显微镜研究纳米大小的物体的动态过程中的液体

Samples fully embedded in liquid can be studied at a nanoscale spatial resolution with Scanning Transmission Electron Microscopy (STEM) using a ...

Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction

超细晶和纳米晶材料的表征采用透射菊池衍射

One of the challenges in microstructure analysis nowadays resides in the reliable and accurate characterization of ultra-fine grained (UFG) and ...

Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets

由界面润湿片的热力学生长触发的液晶中的定向转变

In liquid crystal (LC) physical chemistry, molecules near the surface play a great role in controlling bulk orientation. Thus far, mainly to achieve ...

A Method for Obtaining Serial Ultrathin Sections of Microorganisms in Transmission Electron Microscopy

一种在透射电镜中获取微生物连续超薄切片的方法

Observing cells and cell components in three dimensions at high magnification in transmission electron microscopy requires preparing serial ultrathin ...

All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics

全电子纳秒分辨扫描隧道显微镜: 促进单一掺杂剂电荷动力学的研究

The miniaturization of semiconductor devices to scales where small numbers of dopants can control device properties requires the development of new ...

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

结构转换的原位和原位研究方法: 金属玻璃结晶的实例

We demonstrate the use of two nuclear-based analytical methods that can follow the modifications of microstructural arrangement of iron-based metallic ...

Single-Digit Nanometer Electron-Beam Lithography with an Aberration-Corrected Scanning Transmission Electron Microscope

用畸变校正扫描透射电镜进行单数字纳米电子束光刻

We demonstrate extension of electron-beam lithography using conventional resists and pattern transfer processes to single-digit nanometer dimensions by ...

光诱导 原 位透射电子显微镜观察液-软物质相互作用

光诱导原位透射电子显微镜观察液-软物质相互作用