作者为这个项目确认来自新加坡教育部2级研究基金（项目MOE2013-T2-2-002）资金。

1.准备程序1,3,5-三苯（1） <ol><li>放置苯乙酮的100ml无水乙醇的混合物（4.0克，33.3毫摩尔）和到装有磁力搅拌器，回流冷凝器，氮气进口，鼓泡器，滴液漏斗和温度计的圆底三颈250ml烧瓶中。使用滴液漏斗，在0℃在一个部分的四氯化硅（11.9克，8.0毫升，70.2毫摩尔，2.1当量）添加到该混合物在氮气下。 </li><li>观察的氯化氢气体的演变为10分钟。然后搅拌，在40℃20小时，将反应混合物。 </li><li>冷却反应混合物至23℃，并于200克的水与冰混合，倾（1:1质量比）。 </li><li>用二氯甲烷萃取（2×100毫升）使用提取漏斗所得混合物。 </li><li>用饱和NaCl溶液（100毫升），干燥超过15克无水硫酸镁的洗合并的萃取一次。过滤液体部分关闭，然后我们集中ING旋转蒸发器。 </li><li>通过重结晶从乙醇中纯化产物（溶解于乙醇，随后通过溶剂的部分蒸发最小量，在6℃下保持过夜，并快速过滤），得到2.2克（收率63％）1,3,5-三苯基苯的（1），为浅黄色晶体。 注:1 H-NMR（400兆赫，CDCL 3）:δ= 7.41（M，3H），7.50（M，6H），7.72（D，6H，J = 7.33Hz），7.80（S，3H）13 C-NMR（400兆赫，CDCL 3）:δ= 125.21，127.39，127.57，128.88，141.18，142.38。 </li></ol> 2. LiSES准备与1,3,5-三苯<ol><li>的1,3,5-三苯基苯基LiSES制备 注:本文中使用1,3,5-三苯合成按上述程序。 1,3,5-三苯基于LiSES由李均用x表示TPB（THF）24.7，其中x代表李:PAH摩尔比和TPB表示1,3,5-三苯。李准备点¯xTPB（THF）24.7在通过以下步骤常温充满氩气的手套箱内: <ol><li>量出金属锂，THF和TPB的明确定义的数量分别手套箱内实现Li的目标摩尔组分x TPB（THF）24.7对于x = 1，2，3和4使用41.6毫克，83.3毫克，124.9毫克，166.6毫克李的对于x = 1，2，3和4分别。 </li><li>对于四个LiSES样品被制备，溶解1.84克TPB的12毫升THF的内部四个独立的玻璃瓶表格12毫升每瓶TPB（THF）中24.7的无色溶液。在所有的解决方案，使用0.5M的1,3,5-三苯。 </li><li>加权金属箔丽添加到四瓶和密封用封口膜的瓶子。 </li><li>搅拌在使用玻璃包被的磁性搅拌器以确保金属Li的完全溶解每瓶混合物过夜。 </li></ol></li><li>电导率测量<ol><li>携带所有电导率测量使用基于四电极技术标准电导池探针。小区探头连接到一米。探针具有二级函数来测量溶液的温度在同一时间和同时显示电导率和温度的测量。 </li><li>在此之前的测量，校准用50毫升标准0.01米氯化钾水溶液的电导率探头的手套箱以外的制造商提供的电表。 </li><li>执行所有用于基于1,3,5-三苯基苯LiSES的电导率测量， 为 Li x TPB（THF）24.7对于x = 1，2，3，4的手套箱内。 </li><li>对于这些LiSES中，倾出样品放入一个短玻璃筒和将电极浸入溶液中。记录电导率测量在一段一到两个小时，直到每个样品返回到环境温度。返回到环境温度取每个样品的时间为〜1-2小时。探头W¯¯病保持浸渍样品为电导率测量的整个持续时间英寸</li></ol></li></ol> 3.碗烯<ol><li>基于碗烯-LiSES的制备 注:本文所用的碗烯是使用多级文献程序在物理学院和数学科学学院，南洋理工大学合成9基于碗烯-LiSES被李用x表示心病（THF）247，其中x代表李:PAH摩尔比林表示碗烯。制备的 Li x心病（THF）247在环境温度下通过以下步骤充满氩气的手套箱内: <ol><li>量出金属锂，THF和肺心病的明确定义的数量分别手套箱内达到目标摩尔组成的 Li x心病（THF）247对于x = 1，2，3，4和5，使用4.2毫克，8.3毫克， 12.5毫克，16.6毫克和对于x = 1，2，3，分别为4和5 20.8毫克李。 </li><li> NEXT，对每个五个LiSES样品（X = 1，2，3，4和5）制备，溶解0.15克肺心病的在里面五个独立玻璃瓶12毫升THF中以形成12毫升心病的无色溶液（THF）247在每个瓶子。使用0.05米的碗烯浓度）。 </li><li>接下来，添加称重金属箔李来林（THF）247的五瓶和密封用封口膜的瓶子。 </li><li>搅拌在使用玻璃包被的磁性搅拌器以确保金属锂完全溶解每瓶混合物过夜。 </li></ol></li><li>电导率测量<ol><li>电导率与温度的测量，除去各含有的 Li x心病（THF）247对于x = 1，2，3，4和5分别从手套箱五瓶，用对薄膜的附加层包起来，并浸入其内部填充有干冰的绝缘泡沫塑料容器。 注:LiSES样品没有接触到续与任一湿气或氧气作用而手套箱外，因为将瓶子密封。 </li><li>通过保持每个瓶子浸没在干冰约30分钟被转移回手套箱电导率测量之前冷却每瓶下降到约10℃。 </li><li>吹扫手套箱至少5次，每次冷却的样品，以确保没有缩合痕量的水伴随瓶子放回手套箱的前厅。 </li><li>在其中导电率随温度的测量，收集用于基于萘LiSES试样1的方式，测量锂的电导率相似点¯x心病（THF）247（X = 1，2，3，4，5），历时一至两个小时，才被每个样品返回到环境温度。探针将保持浸渍的样品电导率测量的整个持续时间英寸</li></ol></li></ol>

<ol>
	<li>Tan, K. S., Yazami, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physical-Chemical+and+Electrochemical+Studies+of+the+Lithium+Naphthalenide+Anolyte.">Physical-Chemical and Electrochemical Studies of the Lithium Naphthalenide Anolyte.</a> Electrochim Acta. 180, 629-635 (2015).</li><li>Tan, K. S., Grimsdale, A. C., Yazami, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+and+Characterisation+of+Biphenyl-Based+Lithium+Solvated+Electrons+Solutions.">Synthesis and Characterisation of Biphenyl-Based Lithium Solvated Electrons Solutions.</a> J Phys Chem B. 116, 9056-9060 (2012).</li><li>Rinaldi, A., Tan, K. S., Wijaya, O., Wang, Y., Yazami, R., Menictas, C., Skyllas-Kazacos, M., Lim, T. M., Hughes, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ch.+11.">Ch. 11.</a> Advances in batteries for large- and medium-scale energy storage applications in power systems and electric vehicles. , (2014).</li><li>Wang, Y., Tan, K. S., Yazami, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Materials Challenges In Alternative &amp; Renewable Energy (MCARE 2014). , (2014).</li><li>Yazami, R., Tan, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> in 8th annual Li Battery Power. , (2012).</li><li>Yazami, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hybrid+Electrochemical+Generator+With+A+Soluble+Anode.">Hybrid Electrochemical Generator With A Soluble Anode.</a> US patent. , (2010).</li><li>Yazami, R., Tan, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Liquid+Metal+Battery.">Liquid Metal Battery.</a> US patent. , (2015).</li><li>Lim, Z. 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=Synthesis+and+assessment+of+new+cyclopenta-2,4-dienone+derivatives+for+energy+storage+applications.">Synthesis and assessment of new cyclopenta-2,4-dienone derivatives for energy storage applications.</a> Synthetic Met. 200, 85-90 (2015).</li><li>Butterfield, A. M., Gilomen, B., Siegel, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kilogram-Scale+Production+of+Corannulene.">Kilogram-Scale Production of Corannulene.</a> Org. Process Res. Dev. 16, 664-676 (2012).</li><li>Elmorsy, S. S., Pelter, A., Smith, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+direct+production+of+tri-+and+hexa-substituted+benzenes+from+ketones+under+mild+conditions.">The direct production of tri- and hexa-substituted benzenes from ketones under mild conditions.</a> Tetrahedron Lett. 32, 4175-4176 (1991).</li><li>Zabula, A. V., Filatov, A. S., Spisak, S. N., Rogachev, A. Y., Petrukhina, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Main+Group+Metal+Sandwich:+Five+Lithium+Cations+Jammed+Between+Two+Corannulene+Tetraanion+Decks.">A Main Group Metal Sandwich: Five Lithium Cations Jammed Between Two Corannulene Tetraanion Decks.</a> Science. 333, 1008-1011 (2011).</li></ol>

作者什么都没有透露。

对于基于1,3,5-三苯基苯LiSES，具有光色的样品表明，它具有溶剂化电子的低浓度。 的 Li x TPB（THF）24.7（对于x = 1，2，3，4）展示在其导电率与X A行为类似于看到从联苯和萘1制成LiSES，2。还有在传导性的初始增加与李增加:PAH比为1〜2和导电性在进一步增加的摩尔比为3，4，用李4 TPB（THF）24.7的电导率值比对Li 1 TPB（THF）24.7<...

锂溶剂化电子溶液（LiSES）使用简单的两环多环芳烃（PAH）例如联苯和萘可以潜在地用作在充燃料锂电池1-7液态阳极制备。在LiSES，这些简单的PAH分子担任电子受体从溶解金属锂溶剂化电子。 来自这两个环系统进展，作者自然后进行电导率测量研究其上使用更复杂的多环芳烃制备，与基环戊-2,4-二烯酮衍生物8的起始LiSES。这些多环芳烃包括更大的多环芳烃（&gt;两个苯环），并纳入其芳香环的取代基的多环芳烃。有两个以上的环A大的PAH分子预计容纳每多环芳烃分子更锂原子比任联苯或萘从而导致具有更高的能量密度LiSES。 introduc的目标ING取代成多环芳烃是使PAH更易于接受电子而变得更加稳定在LiSES聚阴离子。 作为不断努力开发具有更高的能量密度LiSES的一部分，本文将通过文献方法9以及1,3,5-三苯做碗烯制备LiSES的特征报告，由城规会略加修改文献10合成。 1,3,5-三苯基苯， 如图1（1），可以被分类为与在位置3两个附加苯基环和相同的环的5联苯衍生物。因为该分子具有4个苯环，应该摄取每分子李，这比对联苯更多的4个原子（每PAH锂的最大2.5摩尔当量在0.5M溶液）和萘（&lt;每分子锂的2.5摩尔当量） 。 碗烯是五环的PAH布置成碗形， 如图1（2）。 Zabula 等人 11表明金属锂溶解于碗烯/四氢呋喃（THF）中的溶液，以形成具有夹在碗烯的两个稳定tetraanions之间的五个Li +离子的溶液的可行性。 <img alt="图1" src="/files/ftp_upload/54366/54366fig1.jpg" /> 图1:1,3,5-三苯基苯的分子结构（1）和碗烯（2）1,3,5-三苯基苯是在相同的环的位置3和5划分为联苯衍生物具有两个附加苯基环。 。碗烯是一种五环PAH与布置成碗状的五个苯环。 <a href="https://www.jove.com/files/ftp_upload/54366/54366fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 因此，无论1,3,5-三苯和碗烯是高能量的潜在候选人密度LiSES。

<table border="0" cellpadding="0" cellspacing="0" width="1005">
	<tbody>
		<tr height="31">
			<td height="31" style="height:31px;width:479px;">Biphenyl Reagentplus, 99.5%</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td style="width:187px;">B34656-1KG</td>
			<td style="width:204px;"></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;">Tetrahydrofuran Anhydrous, 99.9%, Inhibi</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td>401757-100ML</td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;">Iodine, Anhydrous, Beads, -10 Mesh, 99.999% trace metals basis&#160;</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td>451045-25G</td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;">Lithium iodide, anhydrous, 99.95% (metals basis)</td>
			<td style="width:136px;">Alfa Aesar</td>
			<td>40666</td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;width:479px;">Lithium Ion Conducting Glass ceramics (Diameter 1&#34; x 150 mm)&#160;</td>
			<td style="width:136px;">Ohara</td>
			<td style="width:187px;">LICGC(AG01)</td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;width:479px;">Lithium Foil&#160;</td>
			<td style="width:136px;">Alfa Aesar</td>
			<td style="width:187px;">010769.14</td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;width:479px;">Methanol anhydrous, 99.8%</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td>322415-100ML&#160;</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">CompactStat : Electrochemical Analyser with Impedance</td>
			<td style="width:136px;">Ivium Technologies</td>
			<td style="width:187px;">Not Applicable</td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;width:479px;">Cond 3310 Conductivity Meter</td>
			<td style="width:136px;">WTW</td>
			<td style="width:187px;">Not Applicable</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:479px;">Digital Multimeter, Model Fluke 179</td>
			<td style="width:136px;">Fluke Corporation</td>
			<td style="width:187px;">Not Applicable</td>
			<td></td>
		</tr>
		<tr height="120">
			<td height="120" style="height:120px;width:479px;">1,3,5-triphenylbenzene</td>
			<td style="width:136px;">Synthesized from acetpohenone according to procedure described in literature</td>
			<td style="width:187px;"></td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;width:479px;">Silicon tetrachloride</td>
			<td style="width:136px;">Sigma Aldrich</td>
			<td style="width:187px;">215120-100G</td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;width:479px;">acetophenone</td>
			<td style="width:136px;">TCI</td>
			<td style="width:187px;">A0061-500g</td>
			<td></td>
		</tr>
		<tr height="31">
			<td height="31" style="height:31px;width:479px;">Ethanol</td>
			<td style="width:136px;">Merck Millipore</td>
			<td style="width:187px;">1.00983.2511</td>
			<td></td>
		</tr>
	</tbody>
</table>

1,3,5-triphenylbenzene and corannulene as electron receptors for lithium solvated electron solutions

作者对锂溶剂化电子解决方案（LiSES）进行传导的研究报告使用两种类型的多环芳烃（PAH），即1,3,5-三苯和碗烯，作为电子受体的准备。固体多环芳烃首先溶解在四氢呋喃（THF）以形成溶液。然后金属锂溶解于这些PAH / THF溶液，得到蓝色或蓝绿色的解决方案，颜色的指示溶剂化电子的存在。在上1,3,5-三苯基苯基LiSES进行环境温度，由李表示电导率的测量点¯xTPB（THF）24.7（X = 1，2，3，4），表现出与锂的增加电导率的增加: PAH比从X = 1〜2但是，导电性逐渐在进一步增加的比率减小。确立的导电点¯xTPB（THF）24.7对于x = 4比对于x更低</eM&gt; = 1，这样的行为是相似的，从联苯和萘制备的以前报道LiSES的。电导率与基于碗烯-LiSES温度测量，由李用x表示心病（THF）247（X = 1，2，3，4，5），显示出与负斜率的线性关系，表明类似金属的行为，以联苯和萘基于LiSES。

不同量的锂和1,3,5-三苯基苯用THF的混合物之间的反应给出蓝绿色或深蓝色溶液， 如图2的光色表示LiSES的特定样品具有溶剂化电子的低浓度。 1,3,5-三苯基苯演示用的锂增加电导率的增加:在0.5M THF溶液（ 见表1）的PAH比为1〜2。然而，电导率值逐渐在进一步增加的摩尔比减小。李电导率值:PAH = 4比李甚至更低:PAH = 1，此行为是类似于看到从联苯和萘1，2发LiSES。 <table...

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1,3,5-Triphenylbenzene and Corannulene as Electron Receptors for Lithium Solvated Electron Solutions

The authors report on conductivity studies carried out on lithium solvated electron solutions (LiSES) prepared using 1,3,5-triphenylbenzene (TPB) and corannulene as electron receptors.

1,3,5-三苯和碗烯作为电子受体锂溶剂化电子解决方案

The authors report on conductivity studies carried out on lithium solvated electron solutions (LiSES) prepared using two types of polyaromatic ...

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7.6K 次观看.  Nanyang Technological University. The authors report on conductivity studies carried out on lithium solvated electron solutions (LiSES) prepared using 1,3,5-triphenylbenzene (TPB) and corannulene as electron receptors.

视频: 1,3,5-Triphenylbenzene and Corannulene as Electron Receptors for Lithium Solvated Electron Solutions

Quantitative Detection of Trace Explosive Vapors by Programmed Temperature Desorption Gas Chromatography-Electron Capture Detector

The direct liquid deposition of solution standards onto sorbent-filled thermal desorption tubes is used for the quantitative analysis of trace explosive vapor samples. The direct liquid deposition method yields a higher fidelity between the analysis of vapor samples and the analysis of solution standards than using separate injection methods for vapors and solutions, i.e., samples collected on vapor collection tubes and standards prepared in solution vials. Additionally, the method can account for instrumentation losses, which makes it ideal for minimizing variability and quantitative trace chemical detection. Gas chromatography with an electron capture detector is an instrumentation configuration sensitive to nitro-energetics, such as TNT and RDX, due to their relatively high electron affinity. However, vapor quantitation of these compounds is difficult without viable vapor standards. Thus, we eliminate the requirement for vapor standards by combining the sensitivity of the instrumentation with a direct liquid deposition protocol to analyze trace explosive vapor samples.

Trace explosive vapors of TNT and RDX collected on sorbent-filled thermal desorption tubes were analyzed using a programmed temperature desorption system coupled to GC with an electron capture detector. The instrumental analysis is combined with direct liquid deposition method to reduce sample variability and account for instrumentation drift and losses.

定量检测痕量爆炸物蒸气通过程序升温脱附 - 气相色谱 - 电子捕获检测器

The direct liquid deposition of solution standards onto sorbent-filled thermal desorption tubes is used for the quantitative analysis of trace explosive ...

科研

化学

Synthesis of Non-uniformly Pr-doped SrTiO3 Ceramics and Their Thermoelectric Properties

We demonstrate a novel synthesis strategy for the preparation of Pr-doped SrTiO3 ceramics via a combination of solid state reaction and spark plasma sintering techniques. Polycrystalline ceramics possessing a unique morphology can be achieved by optimizing the process parameters, particularly spark plasma sintering heating rate. The phase and morphology of the synthesized ceramics were investigated in detail using X-ray diffraction, scanning electron microcopy and energy-dispersive X-ray spectroscopy. It was observed that the grains of these bulk Pr-doped SrTiO3 ceramics were enhanced with Pr-rich grain boundaries. Electronic and thermal transport properties were also investigated as a function of temperature and doping concentration. Such a microstructure was found to give rise to improved thermoelectric properties. Specifically, it resulted in a significant improvement in carrier mobility and the thermoelectric power factor. Simultaneously, it also led to a marked reduction in the thermal conductivity. As a result, a significant improvement (> 30%) in the thermoelectric figure of merit was achieved for the whole temperature range over all previously reported maximum values for SrTiO3-based ceramics. This synthesis demonstrates the steps for the preparation of bulk polycrystalline ceramics of non-uniformly Pr-doped SrTiO3.

Synthesis of Non-uniformly Pr-doped SrTiO3 Ceramics and Their Thermoelectric Properties

A protocol for the synthesis and processing of polycrystalline SrTiO3 ceramics doped non-uniformly with Pr is presented along with the investigation of their thermoelectric properties.

非均匀掺Pr的SrTiO的合成<sub&gt; 3</sub&gt;陶瓷及其热电性能

We demonstrate a novel synthesis strategy for the preparation of Pr-doped SrTiO3 ceramics via a combination of solid state reaction and spark plasma ...

Characterizing Electron Transport through Living Biofilms

Here we demonstrate the method of electrochemical gating used to characterize electrical conductivity of electrode-grown microbial biofilms under physiologically relevant conditions.1 These measurements are performed on living biofilms in aqueous medium using source and drain electrodes patterned on a glass surface in a specialized configuration referred to as an interdigitated electrode (IDA) array. A biofilm is grown that extends across the gap connecting the source and drain. Potentials are applied to the electrodes (ES and ED) generating a source-drain current (ISD) through the biofilm between the electrodes. The dependency of electrical conductivity on gate potential (the average of the source and drain potentials, EG = [ED + ES]/2) is determined by systematically changing the gate potential and measuring the resulting source-drain current. The dependency of conductivity on gate potential provides mechanistic information about the extracellular electron transport process underlying the electrical conductivity of the specific biofilm under investigation. The electrochemical gating measurement method described here is based directly on that used by M. S. Wrighton2,3 and colleagues and R. W. Murray4,5,6 and colleagues in the 1980&#39;s to investigate thin film conductive polymers.

A protocol for measuring electrical conductivity of living microbial biofilms under physiologically relevant conditions is presented.

通过活生物膜表征电子传输

Here we demonstrate the method of electrochemical gating used to characterize electrical conductivity of electrode-grown microbial biofilms under ...

Synthesis and Characterization of Fe-doped Aluminosilicate Nanotubes with Enhanced Electron Conductive Properties

The goal of the protocol is to synthesize Fe-doped aluminosilicate nanotubes of the imogolite type with the formula (OH)3Al2-xFexO3SiOH. Doping with Fe aims at lowering the band gap of imogolite, an insulator with the chemical formula (OH)3Al2O3SiOH, and at modifying its adsorption properties towards azo-dyes, an important class of organic pollutants of both wastewater and groundwater.
Fe-doped nanotubes are obtained in two ways: by direct synthesis, where FeCl3 is added to an aqueous mixture of the Si and Al precursors, and by post-synthesis loading, where preformed nanotubes are put in contact with a FeCl3&#8226;6H2O aqueous solution. In both synthesis methods, isomorphic substitution of Al3+ by Fe3+ occurs, preserving the nanotube structure. Isomorphic substitution is indeed limited to a mass fraction of ~1.0% Fe, since at a higher Fe content (i.e., a mass fraction of 1.4% Fe), Fe2O3 clusters form, especially when the loading procedure is adopted. The physicochemical properties of the materials are studied by means of X-ray powder diffraction (XRD), N2 sorption isotherms at -196 &#176;C, high resolution transmission electron microscopy (HRTEM), diffuse reflectance (DR) UV-Vis spectroscopy, and &#950;-potential measurements. The most relevant result is the possibility to replace Al3+ ions (located on the outer surface of the nanotubes) by post-synthesis loading on preformed imogolite without perturbing the delicate hydrolysis equilibria occurring during nanotube formation. During the loading procedure, an anionic exchange occurs, where Al3+ ions on the outer surface of the nanotubes are replaced by Fe3+ ions. In Fe-doped aluminosilicate nanotubes, isomorphic substitution of Al3+ by Fe3+ is found to affect the band gap of doped imogolite. Nonetheless, Fe3+ sites on the outer surface of nanotubes are able to coordinate organic moieties, like the azo-dye Acid Orange 7, through a ligand-displacement mechanism occurring in an aqueous solution.

Here, we present a protocol to synthesize and characterize Fe-doped aluminosilicate nanotubes. The materials are obtained by either sol-gel synthesis upon addition of FeCl3&#8226;6H2O to the mixture containing the Si and Al precursors or by post-synthesis ionic exchange of preformed aluminosilicate nanotubes.

以增强电子导电性能的合成与表征Fe掺杂碳纳米管硅铝的

The goal of the protocol is to synthesize Fe-doped aluminosilicate nanotubes of the imogolite type with the formula (OH)3Al2-xFexO3SiOH. Doping with Fe ...

Liquid-cell Transmission Electron Microscopy for Tracking Self-assembly of Nanoparticles

Drying a nanoparticle dispersion is a versatile way to create self-assembled structures of nanoparticles, but the mechanism of this process is not fully understood. We have traced the trajectories of individual nanoparticles using liquid-cell transmission electron microscopy (TEM) to investigate the mechanism of the assembly process. Herein, we present the protocols used for liquid-cell TEM studies of the self-assembly mechanism. First, we introduce the detailed synthetic protocols used to produce uniformly sized platinum and lead selenide nanoparticles. Next, we present the microfabrication processes used to produce liquid cells with silicon nitride or silicon windows and then describe the loading and imaging procedures of the liquid-cell TEM technique. Several notes are included to provide helpful tips for the entire process, including how to manage the fragile cell windows. The individual motions of nanoparticles tracked by liquid-cell TEM revealed that changes in the solvent boundaries caused by evaporation affected the self-assembly process of nanoparticles. The solvent boundaries drove nanoparticles to primarily form amorphous aggregates, followed by flattening of the aggregates to produce a 2-dimensional (2D) self-assembled structure. These behaviors are also observed for different nanoparticle types and different liquid-cell compositions.

Here we introduce experimental protocols for the real-time observation of a self-assembly process using liquid-cell transmission electron microscopy.

用于跟踪纳米粒子自组装的液体细胞透射电子显微镜

Drying a nanoparticle dispersion is a versatile way to create self-assembled structures of nanoparticles, but the mechanism of this process is not fully ...

Obtaining 3D Chemical Maps by Energy Filtered Transmission Electron Microscopy Tomography

Energy filtered transmission electron microscopy tomography (EFTEM tomography) can provide three-dimensional (3D) chemical maps of materials at a nanometric scale. EFTEM tomography can separate chemical elements that are very difficult to distinguish using other imaging techniques. The experimental protocol described here shows how to create 3D chemical maps to understand the chemical distribution and morphology of a material. Sample preparation steps for data segmentation are presented. This protocol permits the 3D distribution analysis of chemical elements in a nanometric sample. However, it should be noted that currently, the 3D chemical maps can only be generated for samples that are not beam sensitive, since the recording of filtered images requires long exposure times to an intense electron beam. The protocol was applied to quantify the chemical distribution of the components of two different heterogeneous catalyst supports. In the first study, the chemical distribution of aluminum and titanium in titania-alumina supports was analyzed. The samples were prepared using the swing-pH method. In the second, the chemical distribution of aluminum and silicon in silica-alumina supports that were prepared using the sol-powder and mechanical mixture methods was examined.

This paper describes a protocol to achieve 3D chemical maps combining energy filtered imaging and electron tomography. The chemical distribution of two catalyst supports formed by elements that are difficult to distinguish by other imaging techniques was studied. Each application consists of mapping overlapped chemical elements - respectively spaced-ionization edges.

通过能量过滤透射电镜成像获得3D 化学图

Energy filtered transmission electron microscopy tomography (EFTEM tomography) can provide three-dimensional (3D) chemical maps of materials at a ...

An Experimental Protocol for Femtosecond NIR/UV - XUV Pump-Probe Experiments with Free-Electron Lasers

This protocol describes key steps in performing and analyzing femtosecond pump-probe experiments that combine a femtosecond optical laser with a free-electron laser. This includes methods to establish the spatial and temporal overlap between the optical and free-electron laser pulses during the experiment, as well as important aspects of the data analysis, such as corrections for arrival time jitter, which are necessary to obtain high-quality pump-probe data sets with the best possible temporal resolution. These methods are demonstrated for an exemplary experiment performed at the FLASH (Free-electron LASer Hamburg) free-electron laser in order to study ultrafast photochemistry in gas-phase molecules by means of velocity map ion imaging. However, most of the strategies are also applicable to similar pump-probe experiments using other targets or other experimental techniques.

This protocol describes the key steps for performing and analyzing pump-probe experiments combining a femtosecond optical laser with a free-electron laser in order to study ultrafast photochemical reactions in gas-phase molecules.

用自由电子激光器进行飞秒近红外/紫外 XUV 泵-探针实验的实验协议

This protocol describes key steps in performing and analyzing femtosecond pump-probe experiments that combine a femtosecond optical laser with a ...

Microfluidic Chips for In Situ Crystal X-ray Diffraction and In Situ Dynamic Light Scattering for Serial Crystallography

This protocol describes fabricating microfluidic devices with low X-ray background optimized for goniometer based fixed target serial crystallography. The devices are patterned from epoxy glue using soft lithography and are suitable for in situ X-ray diffraction experiments at room temperature. The sample wells are lidded on both sides with polymeric polyimide foil windows that allow diffraction data collection with low X-ray background. This fabrication method is undemanding and inexpensive. After the sourcing of a SU-8 master wafer, all fabrication can be completed outside of a cleanroom in a typical research lab environment. The chip design and fabrication protocol utilize capillary valving to microfluidically split an aqueous reaction into defined nanoliter sized droplets. This loading mechanism avoids the sample loss from channel dead-volume and can easily be performed manually without using pumps or other equipment for fluid actuation. We describe how isolated nanoliter sized drops of protein solution can be monitored in situ by dynamic light scattering to control protein crystal nucleation and growth. After suitable crystals are grown, complete X-ray diffraction datasets can be collected using goniometer based in situ fixed target serial X-ray crystallography at room temperature. The protocol provides custom scripts to process diffraction datasets using a suite of software tools to solve and refine the protein crystal structure. This approach avoids the artefacts possibly induced during cryo-preservation or manual crystal handling in conventional crystallography experiments. We present and compare three protein structures that were solved using small crystals with dimensions of approximately 10-20 &#181;m grown in chip. By crystallizing and diffracting in situ, handling and hence mechanical disturbances of fragile crystals is minimized. The protocol details how to fabricate a custom X-ray transparent microfluidic chip suitable for in situ serial crystallography. As almost every crystal can be used for diffraction data collection, these microfluidic chips are a very efficient crystal delivery method.

Microfluidic Chips for In Situ Crystal X-ray Diffraction and In Situ Dynamic Light Scattering for Serial Crystallography

This protocol describes in detail how to fabricate and operate microfluidic devices for X-ray diffraction data collection at room temperature. Additionally, it describes how to monitor protein crystallization by dynamic light scattering and how to process and analyze obtained diffraction data.

用于原位晶体 x 射线衍射和原位的微流控芯片系列晶体学的动态光散射

This protocol describes fabricating microfluidic devices with low X-ray background optimized for goniometer based fixed target serial crystallography. The ...

A Rapid Synthesis Method for Au, Pd, and Pt Aerogels Via Direct Solution-Based Reduction

Here, a method to synthesize gold, palladium, and platinum aerogels via a rapid, direct solution-based reduction is presented. The combination of various precursor noble metal ions with reducing agents in a 1:1 (v/v) ratio results in the formation of metal gels within seconds to minutes compared to much longer synthesis times for other techniques such as sol-gel. Conducting the reduction step in a microcentrifuge tube or small volume conical tube facilitates a proposed nucleation, growth, densification, fusion, equilibration model for gel formation, with final gel geometry smaller than the initial reaction volume. This method takes advantage of the vigorous hydrogen gas evolution as a by-product of the reduction step, and as a consequence of reagent concentrations. The solvent accessible specific surface area is determined with both electrochemical impedance spectroscopy and cyclic voltammetry. After rinsing and freeze drying, the resulting aerogel structure is examined with scanning electron microscopy, X-ray diffractometry, and nitrogen gas adsorption. The synthesis method and characterization techniques result in a close correspondence of aerogel ligament sizes. This synthesis method for noble metal aerogels demonstrates that high specific surface area monoliths may be achieved with a rapid and direct reduction approach.

A rapid, direct solution-based reduction synthesis method to obtain Au, Pd, and Pt aerogels is presented.

直接溶液还原法快速合成金、钯、铂气凝胶的研究

Here, a method to synthesize gold, palladium, and platinum aerogels via a rapid, direct solution-based reduction is presented. The combination of various ...

Pretargeted Radioimmunotherapy Based on the Inverse Electron Demand Diels-Alder Reaction

While radioimmunotherapy (RIT) is a promising approach for the treatment of cancer, the long pharmacokinetic half-life of radiolabeled antibodies can result in high radiation doses to healthy tissues. Perhaps not surprisingly, several different strategies have been developed to circumvent this troubling limitation. One of the most promising of these approaches is pretargeted radioimmunotherapy (PRIT). PRIT is predicated on decoupling the radionuclide from the immunoglobulin, injecting them separately, and then allowing them to combine in vivo at the target tissue. This approach harnesses the exceptional tumor-targeting properties of antibodies while skirting their pharmacokinetic drawbacks, thereby lowering radiation doses to non-target tissues and facilitating the use of radionuclides with half-lives that are considered too short for use in traditional radioimmunoconjugates. Over the last five years, our laboratory and others have developed an approach to in vivo pretargeting based on the inverse electron-demand Diels-Alder (IEDDA) reaction between trans-cyclooctene (TCO) and tetrazine (Tz). This strategy has been successfully applied to pretargeted positron emission tomography (PET) and single-photon emission computed tomography (SPECT) imaging with a variety of antibody-antigen systems. In a pair of recent publications, we have demonstrated the efficacy of IEDDA-based PRIT in murine models of pancreatic ductal adenocarcinoma and colorectal carcinoma. In this protocol, we describe protocols for PRIT using a 177Lu-DOTA-labeled tetrazine radioligand ([177Lu]Lu-DOTA-PEG7-Tz) and a TCO-modified variant of the colorectal cancer targeting huA33 antibody (huA33-TCO). More specifically, we will describe the construction of huA33-TCO, the synthesis and radiolabeling of [177Lu]Lu-DOTA-PEG7-Tz, and the performance of in vivo biodistribution and longitudinal therapy studies in murine models of colorectal carcinoma.

This protocol describes the synthesis and characterization of a trans-cyclooctene (TCO)-modified antibody and a 177Lu-labeled tetrazine (Tz) radioligand for pretargeted radioimmunotherapy (PRIT). In addition, it details the use of these two constructs for in vivo biodistribution and longitudinal therapy studies in a murine model of colorectal cancer.

基于逆电子需求函数-alder 反应的隐形放射免疫治疗

While radioimmunotherapy (RIT) is a promising approach for the treatment of cancer, the long pharmacokinetic half-life of radiolabeled antibodies can ...