This work was supported by the New Professor Research Foundation Program, funded by Gyeongsang National University (Grant Number 2015-04-020).

1.植物苯酚衍生的高分子染料的制备<ol><li> 32毫升的100mM乙酸钠缓冲液（pH5.0）和8毫升无水乙醇中的儿茶素水合物（0.1克） - 溶解儿茶酚（0.1克）和（+）。 </li><li>添加10毫克的T.云芝漆酶的catechol-和含儿茶素的缓冲区。混合大力和将溶液倒入方形培养皿。在室温下孵育皿在24小时的振荡培养箱（25转）。从透明的暗黑色溶液的显着的颜色变化可以用肉眼漆酶诱导的偶合反应之后观察到。 </li><li>离心溶液10分钟以20,000 xg离心以降速不溶的聚合物颗粒。使用进一步的脱盐深黑上清。 </li><li>脱盐用5 kDa的超滤光盘反应溶液中。浓缩反应体积至20ml通过超滤后，通过加入300毫升蒸馏水交换反应缓冲液。最后，使用过滤，浓缩溶液的体积至25ml。 </li></ol> 2.灰色头发角蛋白染色解决方案<ol><li>准备以下六个聚合物溶液:聚合物染料，聚合物染料/ 硫酸亚铁，聚合物染料/ 硫酸亚铁在pH为3的水，聚合物染料/ 硫酸亚铁在pH为11的水，聚合物染料/ 硫酸亚铁用乙酸，和聚合物染料/硫酸亚铁4与氨。 <ol><li>为聚合染料，混合溶于5ml蒸馏水用1ml脱盐聚合物染料（1.4）的。 </li><li>为媒染剂溶液，从步骤2.1.1添加0.33克的FeSO 4的混合物中。大力涡旋溶解硫酸亚铁完全。 </li><li>对于pH为3或11的水溶液，调整用1N HCl或1N的NaOH5毫升蒸馏水的pH值。再加入1毫升脱盐聚合染料（1.4）和0.33克硫酸亚铁的。 </li><li>对于乙酸 - 或氨处理的溶液，混匀1.0毫升GL的acial乙酸或1.0毫升氨水用5ml蒸馏水。再加入1毫升脱盐聚合染料（1.4）和0.33克硫酸亚铁的。 </li></ol></li><li>于6ml蒸馏水中，有或没有0.33克的FeSO 4的儿茶素水合物（0.1克），浸泡在头发-为对植物的单体，混合邻苯二酚（0.1克）和（+）。 </li><li>如从步骤2.1和2.2的染色溶液制备不久，完全浸泡在溶液5厘米长的灰色人发束（0.2克）。孵育在32℃的发束在2.5小时的摇动培养箱（160转）。 </li><li>此后，取出发束，用流水冲洗。使用电子头发干燥器以除去水分。引起的聚合物染料颜色变化可以用肉眼可视化。 <ol><li>以获得颜色参数（ 即，L *，a *和b *的 ），使用根据制造商的协议的常规色度计。揉碎头发Ťresses成一团，从而使他们能够用比色计的透镜来测量。重复在毛发上与色度计透镜的不同区域这一过程。 </li><li>测量每个染色发辫七倍的颜色参数。计算平均值和所述参数的标准偏差。使用下式计算ΔE:[（100 - L *）2 +（A *）2 +（B *）2] 1/2。 </li></ol></li></ol> 3.颜色耐久性试验<ol><li>在40毫升的蒸馏水中溶解200毫克十二烷基硫酸钠（SDS）的。完全浸泡染发在含有SDS的水，在室温下5分钟。取出发束，然后用足够的自来水冲洗一下，以除去洗涤剂。使用电子头发干燥器以除去水分。 </li><li>以获得颜色参数（ 即，L *，a *和b *的 ），采用根据厂家专业的常规色度计呃的协议。重复步骤3.1与同染发描述再次浸泡，然后再测量参数。 </li><li>溶解800毫克的SDS在40毫升的蒸馏水。如步骤3.1中所述，多重复用相同的染发浸泡两次。总体而言，共四次对待每染发束用SDS溶液。 </li></ol>

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The authors declare that they have no competing financial interests.

有趣的是，我们的方法减少花染的头发角蛋白具有天然酚类物质氧化引起的聚合反应的时间。它还通过聚合物染料的简单的操作，如改变pH值和施加媒染剂诱导的毛发颜色多样。 在头发角蛋白与植物酚类的漆酶催化氧化的原位培养过于需要很长的培育时间以达到有效的染色7。这种缓染动力学可能是由于植物酚类的差结合能力，并具有非常低的分子量，?...

漆酶是氧化酶是对酚和多酚化合物的活性。他们已经在各种生物体，包括植物，真菌，昆虫和细菌被确定。他们的行动酶有助于几种形态的现象1。酶催化底物的单电子氧化，导致在被进一步耦合到小的有机物和固体表面自由基的形成。这种耦合过程导致的低聚物和聚合物的合成和表面functionalizations 2,3。当漆酶底物是从天然来源，如植物酚类，酶促反应是相对于绿色化学的极大兴趣。这里，两种反应物和催化剂是从天然来源。此外，所得到的产品类似于天然产物，因为整个反应模拟天然酚的体内合成聚合物，包括植物木质素，聚（flavono编号），和腐殖质其中小植物酚类化合物是高度交联通过氧化酶诱导的自由基偶合4。 从植物衍生的酚的漆酶催化的偶联反应衍生的产品可以用于通过原位孵育染灰发，并且可以开发作为替代市售染料1。这样的替代是重要的，因为是基于对苯二胺（PPD）商业染发剂，PPD相关二胺化合物，以及过氧化氢，这已被证明是有毒的，致癌和过敏人类5,6在漆酶催化的偶联反应中，漆酶和植物酚类功能替换分别过氧化氢和对苯二胺，7。但是，基于漆酶系统的染色速度比商用一个慢得多。在一般情况下，基于PPD-染色剂需要不到一小时，以实现在角蛋白毛发有效的颜色变化，而基于漆酶反应需要过夜温育7。缓慢染色动力学可以通过两种可能的现象进行说明。第一，使用低pH值缓冲液（ 例如，pH值为5），以最大限度地提高漆酶活性已被观察到降低在角蛋白基质溶胀，从而抑制染料成矩阵的深穿透程度。实际上，代理允许染色反应在高pH条件下进行已被证明是不可或缺的商用头发染色产品8。其次，聚合反应过程中表现出很强的吸附到角质表面可能发色团分子的数量已经被证明是成比例的孵育时间（ 即，聚合的程度）。例如，多巴胺聚多巴胺的转化显示出诱导到许多表面，这是伴随着黑色9的形成强粘合力。&lt;/ P&gt; 在目前的工作中，预合成由T.获得的聚合物产品云芝儿茶素和儿茶酚的漆酶催化氧化反应被用来治疗头发角蛋白染色。我们推测的聚合物的吸附能力将比单体植物酚的强得多，他们将最初形成的低分子量的低聚物。结果表明，使用预先合成的聚合物时，酶促氧化电源不再需要。这表明，pH值可被控制，并且金属离子可以染发处理中使用，而不管酶的活性。这个协议提供了一个简单而快速的方法，同时使用生态友好的和可再生的来自植物的酚（ 图1）的染料在颜色的各种色调角蛋白毛发。

<table border="0" cellpadding="0" cellspacing="0" width="802">
	<tbody>
		<tr height="32">
			<td height="32" style="height:32px;width:208px;">Sodium dodecyl Sulfate</td>
			<td style="width:205px;">Promega</td>
			<td style="width:208px;">H5114</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">Laccase from Trametes versicolor</td>
			<td style="width:205px;">Sigma</td>
			<td style="width:208px;">38429-1G</td>
			<td style="width:181px;">Enzyme activity is denoted as 0.53 U/mg</td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">(+)-catechin hydrate</td>
			<td style="width:205px;">Sigma</td>
			<td style="width:208px;">C1251-5G</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">1,2-dihydroxybenzene (catechol)</td>
			<td style="width:205px;">Sigma</td>
			<td style="width:208px;">135011-5G</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">Ammonia water&#160;</td>
			<td style="width:205px;">Duksan</td>
			<td style="width:208px;">701</td>
			<td style="width:181px;">Ammonia contents is denoted as 25 ~ 30%</td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">Acetic acid, glacial</td>
			<td style="width:205px;">Duksan</td>
			<td style="width:208px;">448</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:208px;">Iron (II) sulfate heptahydrate</td>
			<td style="width:205px;">JUNSEI</td>
			<td style="width:208px;">83380-1250</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:208px;">Ultracell 5kDa</td>
			<td style="width:205px;">Amicon</td>
			<td style="width:208px;">PLCC06210</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:208px;">Stirred ultrafiltration cells</td>
			<td style="width:205px;">Millipore</td>
			<td style="width:208px;">Model 8200</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:208px;">Human gray hair</td>
			<td style="width:205px;">PheonixKorea</td>
			<td style="width:208px;">Not available</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:208px;">Colorimeter</td>
			<td style="width:205px;">SPEC</td>
			<td style="width:208px;">JCS-10</td>
			<td style="width:181px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:208px;">Square dish</td>
			<td style="width:205px;">SPL</td>
			<td style="width:208px;">10125</td>
			<td style="width:181px;">125 * 125 * 20 (mm)</td>
		</tr>
	</tbody>
</table>

synthesis of plant phenol-derived polymeric dyes for direct or mordant-based hair dyeing

有效的头发染色通过在角蛋白毛发与植物酚的真菌漆酶催化的聚合的产物的原位孵育先前已经证明。然而，染色过程需要较长的时间相比，商业的染发产品来完成。为了克服这一瓶颈，预先合成的栓的云芝上儿茶素和儿茶酚漆酶氧化反应的聚合物产品，无论是有或没有媒剂（ 例如， 硫酸亚铁），这里被用来实现永久角蛋白毛发染色的各种颜色和色调。在酸性醋酸钠缓冲液漆酶耦合作用厂酚之间的反应后，导致了深黑的颜色。然后将着色染料产物脱盐并浓缩，之后用超滤。染料，有或没有媒剂，导致在灰色人类头发的WiΔE值（ 即，色差值）显著增加薄2.5小时。此外，不同的角蛋白颜色和色调取决于媒染和pH值的变化被诱导。染色的毛发还表现出对洗涤剂处理有很强的抵抗力，表明我们的方法可以产生永久染发。总的来说，我们的工作提供了新颖的洞察显影生态友好的染发方法以替代商业有毒二胺类染料。

首先，聚合物染料的染色能力相比，来自植物的单体（ 即，儿茶素和儿茶酚）的。的聚合物染料诱导的灰色角蛋白毛发（ 图2A和图3）的颜色显著变化，而头发的先天灰色保持与植物的单体非常稳定的（ 数据未显示 ）。然后媒染对聚合物产品的染色能力剂的作用进行了评价。如在图2A中看到的，除了Fe离子导致的灰...

Watch this Scientific Journal Video about Synthesis of Plant Phenol-derived Polymeric Dyes for Direct or Mordant-based Hair Dyeing at JoVE.com

Synthesis of Plant Phenol-derived Polymeric Dyes for Direct or Mordant-based Hair Dyeing

Here, we present a protocol to use pre-synthesized polymeric products derived from fungal laccase-catalyzed polymerization of plant phenols, either with or without mordant agents (e.g., FeSO4), to induce detergent-resistant keratin hair dyeing within 2.5 hours.

对于直接或媒介为基础的头发染色厂苯酚衍生的高分子染料的合成

Effective hair dyeing through in situ incubation of keratin hair with the products of fungal laccase-catalyzed polymerization of plant phenols has been ...

synthesis-plant-phenol-derived-polymeric-dyes-for-direct-or-mordant

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9.2K 次观看.  Gyeongsang National University. Here, we present a protocol to use pre-synthesized polymeric products derived from fungal laccase-catalyzed polymerization of plant phenols, either with or without mordant agents (e.g., FeSO4), to induce detergent-resistant keratin hair dyeing within 2.5 hours.

视频: Synthesis of Plant Phenol-derived Polymeric Dyes for Direct or Mordant-based Hair Dyeing

Microwave-assisted Intramolecular Dehydrogenative Diels-Alder Reactions for the Synthesis of Functionalized Naphthalenes/Solvatochromic Dyes

Functionalized naphthalenes have applications in a variety of research fields ranging from the synthesis of natural or biologically active molecules to the preparation of new organic dyes. Although numerous strategies have been reported to access naphthalene scaffolds, many procedures still present limitations in terms of incorporating functionality, which in turn narrows the range of available substrates. The development of versatile methods for direct access to substituted naphthalenes is therefore highly desirable.
The Diels-Alder (DA) cycloaddition reaction is a powerful and attractive method for the formation of saturated and unsaturated ring systems from readily available starting materials. A new microwave-assisted intramolecular dehydrogenative DA reaction of styrenyl derivatives described herein generates a variety of functionalized cyclopenta[b]naphthalenes that could not be prepared using existing synthetic methods. When compared to conventional heating, microwave irradiation accelerates reaction rates, enhances yields, and limits the formation of undesired byproducts.
The utility of this protocol is further demonstrated by the conversion of a DA cycloadduct into a novel solvatochromic fluorescent dye via a Buchwald-Hartwig palladium-catalyzed cross-coupling reaction. Fluorescence spectroscopy, as an informative and sensitive analytical technique, plays a key role in research fields including environmental science, medicine, pharmacology, and cellular biology. Access to a variety of new organic fluorophores provided by the microwave-assisted dehydrogenative DA reaction allows for further advancement in these fields.

Microwave-assisted intramolecular dehydrogenative Diels-Alder (DA) reactions provide concise access to functionalized cyclopenta[b]naphthalene building blocks. The utility of this methodology is demonstrated by one-step conversion of the dehydrogenative DA cycloadducts into novel solvatochromic fluorescent dyes via Buchwald-Hartwig palladium-catalyzed cross-coupling reactions.

微波辅助分子内Diels-Alder反应的功能化萘/变色染料的合成脱氢

Functionalized naphthalenes have applications in a variety of research fields ranging from the synthesis of natural or biologically active molecules to ...

科研

化学

Synthesis of Indoxyl-glycosides for Detection of Glycosidase Activities

Indoxyl glycosides proved to be valuable and versatile tools for monitoring glycosidase activities. Indoxyls are released by enzymatic hydrolysis and are rapidly oxidized, for example by atmospheric oxygen, to indigo type dyes. This reaction enables fast and easy screening in vivo without isolation or purification of enzymes, as well as rapid tests on agar plates or in solution (e.g., blue-white screening, micro-wells) and is used in biochemistry, histochemistry, bacteriology and molecular biology. Unfortunately the synthesis of such substrates proved to be difficult, due to various side reactions and the low reactivity of the indoxyl hydroxyl function. Especially for glucose type structures low yields were observed. Our novel approach employs indoxylic acid ester as key intermediates. Indoxylic acid esters with varied substitution patterns were prepared on scalable pathways. Phase transfer glycosylations with those acceptors and peracetylated glycosyl halides can be performed under common conditions in high yields. Ester cleavage and subsequent mild silver mediated glycosylation yields the peracetylated indoxyl glycosides in high yields. Finally deprotection is performed according to Zempl&#233;n.

Indoxyl glycosides are well-established and widely used tools for enzyme screening and enzyme activity monitoring. Especially for glucose type structures previous syntheses proved to be challenging and low yielding. Our novel approach employs indoxylic acid esters as precious intermediates to yield a considerable number of indoxyl glycosides in good yields.

的吲哚酚苷的检测糖苷酶活动的合成

Indoxyl glycosides proved to be valuable and versatile tools for monitoring glycosidase activities. Indoxyls are released by enzymatic hydrolysis and are ...

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products

The guanidine functional group, displayed most prominently in the amino acid arginine, one of the fundamental building blocks of life, is an important structural element found in many complex natural products and pharmaceuticals. Owing to the continual discovery of new guanidine-containing natural products and designed small molecules, rapid and efficient guanidinylation methods are of keen interest to synthetic and medicinal organic chemists. Because the nucleophilicity and basicity of guanidines can affect subsequent chemical transformations, traditional, indirect guanidinylation is typically pursued. Indirect methods commonly employ multiple protection steps involving a latent amine precursor, such as an azide, phthalimide, or carbamate. By circumventing these circuitous methods and employing a direct guanidinylation reaction early in the synthetic sequence, it was possible to forge the linear terminal guanidine containing backbone of clavatadine A to realize a short and streamlined synthesis of this potent factor XIa inhibitor. In practice, guanidine hydrochloride is elaborated with a carefully constructed protecting array that is optimized to survive the synthetic steps to come. In the preparation of clavatadine A, direct guanidinylation of a commercially available diamine eliminated two unnecessary steps from its synthesis. Coupled with the wide variety of known guanidine protecting groups, direct guanidinylation evinces a succinct and efficient practicality inherent to methods that find a home in a synthetic chemist&#39;s toolbox.

Here, we present a protocol for direct, early stage guanidinylation that enables rapid total synthesis of aminoguanidine-containing small organic molecules. An advanced synthetic intermediate used in the synthesis of a blood coagulation factor XIa inhibitor was prepared using this protocol.

一个直接的，早期胍基协议的复杂含氨基胍，天然产物合成

The guanidine functional group, displayed most prominently in the amino acid arginine, one of the fundamental building blocks of life, is an important ...

Hydroquinone Based Synthesis of Gold Nanorods

Gold nanorods are an important kind of nanoparticles characterized by peculiar plasmonic properties. Despite their widespread use in nanotechnology, the synthetic methods for the preparation of gold nanorods are still not fully optimized. In this paper we describe a new, highly efficient, two-step protocol based on the use of hydroquinone as a mild reducing agent. Our approach allows the preparation of nanorods with a good control of size and aspect ratio (AR) simply by varying the amount of hexadecyl trimethylammonium bromide (CTAB) and silver ions (Ag+) present in the "growth solution". By using this method, it is possible to markedly reduce the amount of CTAB, an expensive and cytotoxic reagent, necessary to obtain the elongated shape. Gold nanorods with an aspect ratio of about 3 can be obtained in the presence of just 50 mM of CTAB (versus 100 mM used in the standard protocol based on the use of ascorbic acid), while shorter gold nanorods are obtained using a concentration as low as 10 mM.

This paper describes a protocol for the synthesis of gold nanorods, based on the use of hydroquinone as reducing agent, plus the different mechanisms for controlling their size and aspect ratio.

金纳米棒基于对苯二酚合成

Gold nanorods are an important kind of nanoparticles characterized by peculiar plasmonic properties. Despite their widespread use in nanotechnology, the ...

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

We demonstrate a method for the synthesis of cyclic polymers and a protocol for characterizing their diffusive motion in a melt state at the single molecule level. An electrostatic self-assembly and covalent fixation (ESA-CF) process is used for the synthesis of the cyclic poly(tetrahydrofuran) (poly(THF)). The diffusive motion of individual cyclic polymer chains in a melt state is visualized using single molecule fluorescence imaging by incorporating a fluorophore unit in the cyclic chains. The diffusive motion of the chains is quantitatively characterized by means of a combination of mean-squared displacement (MSD) analysis and a cumulative distribution function (CDF) analysis. The cyclic polymer exhibits multiple-mode diffusion which is distinct from its linear counterpart. The results demonstrate that the diffusional heterogeneity of polymers that is often hidden behind ensemble averaging can be revealed by the efficient synthesis of the cyclic polymers using the ESA-CF process and the quantitative analysis of the diffusive motion at the single molecule level using the MSD and CDF analyses.

A protocol for the synthesis and characterization of diffusive motion of cyclic polymers at the single molecule level is presented.

环状聚合物的合成及其在熔融状态扩散运动的表征在单分子水平

We demonstrate a method for the synthesis of cyclic polymers and a protocol for characterizing their diffusive motion in a melt state at the single ...

Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of Chalcogenidoplumbates(II or IV)

The phases of &#34;PbCh2&#34; (Ch = Se, Te) are obtained from solid-state syntheses (i.e., by the fusion of the elements under inert conditions in silica glass ampules). Reduction of such phases by elemental alkaline metals in amines affords crystalline chalcogenidoplumbate(II) salts comprised of [PbTe3]2- or [Pb2Ch3]2- anions, depending upon which sequestering agent for the cations is present: crown ethers, like 18-crown-6, or cryptands, like [2.2.2]crypt. Reactions of solutions of such anions with transition-metal compounds yield (poly-)chalcogenide anions or transition-metal chalcogenide clusters, including one with a &#181;-PbSe ligand (i.e., the heaviest-known CO homolog).
In contrast, the solid-state synthesis of a phase of the nominal composition &#34;K2PbSe2&#34; by successive reactions of the elements and by the subsequent solvothermal treatment in amines yields the first non-oxide/halide inorganic lead(IV) compound: a salt of the ortho-selenidoplumbate(IV) anion [PbSe4]4-. This was unexpected due to the redox potentials of Pb(IV) and Se(-II). Such methods can further be applied to other elemental combinations, leading to the formation of solutions with binary [HgTe2]2- or [BiSe3]3- anions, or to large-scale syntheses of K2Hg2Se3 or K3BiSe3 via the solid-state route.
All compounds are characterized by single-crystal X-ray diffraction and elemental analysis; solutions of plumbate salts can be investigated by 205Pb and 77Se or 127Te NMR techniques. Quantum chemical calculations using density functional theory methods enable energy comparisons. They further allow for insights into the electronic configuration and thus, the bonding situation. Molecular Rh-containing Chevrel-type compounds were found to exhibit delocalized mixed valence, whereas similar telluridopalladate anions are electron-precise; the cluster with the &#181;-PbSe ligand is energetically favored over a hypothetical CO analog, in line with the unsuccessful attempt at its synthesis. The stability of formal Pb(IV) within the [PbSe4]4- anion is mainly due to a suitable stabilization within the crystal lattice.

Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV

The synthesis of chalcogenidoplumbates(II,IV) via the in situ reduction of nominal "PbCh2" (Ch = Chalcogen) and via a solid-state reaction and subsequent solvothermal reactions is presented. Additionally, reactivities of plumbate(II) solutions are portrayed, which yield the heaviest-known CO homolog known to date: the &#181;-PbSe ligand.

结合固态和基于解决方案的技术合成及Chalcogenidoplumbates的反应（II或IV）

The phases of &#34;PbCh2&#34; (Ch = Se, Te) are obtained from solid-state syntheses (i.e., by the fusion of the elements under inert conditions in silica ...

Direct Imaging of Laser-driven Ultrafast Molecular Rotation

We present a method for visualizing laser-induced, ultrafast molecular rotational wave packet dynamics. We have developed a new 2-dimensional Coulomb explosion imaging setup in which a hitherto-impractical camera angle is realized. In our imaging technique, diatomic molecules are irradiated with a circularly polarized strong laser pulse. The ejected atomic ions are accelerated perpendicularly to the laser propagation. The ions lying in the laser polarization plane are selected through the use of a mechanical slit and imaged with a high-throughput, 2-dimensional detector installed parallel to the polarization plane. Because a circularly polarized (isotropic) Coulomb exploding pulse is used, the observed angular distribution of the ejected ions directly corresponds to the squared rotational wave function at the time of the pulse irradiation. To create a real-time movie of molecular rotation, the present imaging technique is combined with a femtosecond pump-probe optical setup in which the pump pulses create unidirectionally rotating molecular ensembles. Due to the high image throughput of our detection system, the pump-probe experimental condition can be easily optimized by monitoring a real-time snapshot. As a result, the quality of the observed movie is sufficiently high for visualizing the detailed wave nature of motion. We also note that the present technique can be implemented in existing standard ion imaging setups, offering a new camera angle or viewpoint for the molecular systems without the need for extensive modification.

We present a protocol for creating a real-time movie of a molecular rotational wave packet using a high-resolution Coulomb explosion imaging setup.

激光驱动的超快分子旋转直接成像

We present a method for visualizing laser-induced, ultrafast molecular rotational wave packet dynamics. We have developed a new 2-dimensional Coulomb ...

Microfluidic-based Synthesis of Covalent Organic Frameworks (COFs): A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

Covalent Organic Frameworks (COFs) are a class of porous covalent materials which are frequently synthesized as unprocessable crystalline powders. The first COF was reported in 2005 with much effort centered on the establishment of new synthetic routes for its preparation. To date, most available synthetic methods for COF synthesis are based on bulk mixing under solvothermal conditions. Therefore, there is increasing interest in developing systematic protocols for COF synthesis that provide for fine control over reaction conditions and improve COF processability on surfaces, which is essential for their use in practical applications. Herein, we present a novel microfluidic-based method for COF synthesis where the reaction between two constituent building blocks, 1,3,5-benzenetricarbaldehyde (BTCA) and 1,3,5-tris(4-aminophenyl)benzene (TAPB), takes place under controlled diffusion conditions and at room temperature. Using such an approach yields sponge-like, crystalline fibers of a COF material, hereafter called MF-COF. The mechanical properties of MF-COF and the dynamic nature of the approach allow the continuous production of MF-COF fibers and their direct printing onto surfaces. The general method opens new potential applications requiring advanced printing of 2D or 3D COF structures on flexible or rigid surfaces.

Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

We present a novel microfluidic-based method for synthesis of covalent organic frameworks (COFs). We demonstrate how this approach can be used to produce continuous COF fibers, and also 2D or 3D COF structures on surfaces.

基于微流体的共价有机骨架（COFs）的合成:用于连续生产COF纤维和直接印刷在表面上的工具

Covalent Organic Frameworks (COFs) are a class of porous covalent materials which are frequently synthesized as unprocessable crystalline powders. The ...

Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain

Barium titanate (BaTiO3, hereafter BT) is an established ferroelectric material first discovered in the 1940s and still widely used because of its well-balanced ferroelectricity, piezoelectricity, and dielectric constant. In addition, BT does not contain any toxic elements. Therefore, it is considered to be an eco-friendly material, which has attracted considerable interest as a replacement for lead zirconate titanate (PZT). However, bulk BT loses its ferroelectricity at approximately 130 &#176;C, thus, it cannot be used at high temperatures. Because of the growing demand for high-temperature ferroelectric materials, it is important to enhance the thermal stability of ferroelectricity in BT. In previous studies, strain originating from the lattice mismatch at hetero-interfaces has been used. However, the sample preparation in this approach requires complicated and expensive physical processes, which are undesirable for practical applications.
In this study, we propose a chemical synthesis of a porous material as an alternative means of introducing strain. We synthesized a porous BT thin film using a surfactant-assisted sol-gel method, in which self-assembled amphipathic surfactant micelles were used as an organic template. Through a series of studies, we clarified that the introduction of pores had a similar effect on distorting the BT crystal lattice, to that of a hetero-interface, leading to the enhancement and stabilization of ferroelectricity. Owing to its simplicity and cost effectiveness, this fabrication process has considerable advantages over conventional methods.

Here, we present a protocol for the synthesis of porous barium titanate (BaTiO3) thin film by a surfactant-assisted sol-gel method, in which self-assembled amphipathic surfactant micelles are used as an organic template.

孔隙诱导应变法合成多孔钛酸钡薄膜及铁电相热稳定性

Barium titanate (BaTiO3, hereafter BT) is an established ferroelectric material first discovered in the 1940s and still widely used because of its ...

Synthesis of Substrate-Bound Au Nanowires Via an Active Surface Growth Mechanism

Advancing synthetic capabilities is important for the development of nanoscience and nanotechnology. The synthesis of nanowires has always been a challenge, as it requires asymmetric growth of symmetric crystals. Here, we report a distinctive synthesis of substrate-bound Au nanowires. This template-free synthesis employs thiolated ligands and substrate adsorption to achieve the continuous asymmetric deposition of Au in solution at ambient conditions. The thiolated ligand prevented the Au deposition on the exposed surface of the seeds, so the Au deposition only occurs at the interface between the Au seeds and the substrate. The side of the newly deposited Au nanowires is immediately covered with the thiolated ligand, while the bottom facing the substrate remains ligand-free and active for the next round of Au deposition. We further demonstrate that this Au nanowire growth can be induced on various substrates, and different thiolated ligands can be used to regulate the surface chemistry of the nanowires. The diameter of the nanowires can also be controlled with mixed ligands, in which another &#34;bad&#34; ligand could turn on the lateral growth. With the understanding of the mechanism, Au nanowire-based nanostructures can be designed and synthesized.

We report a solution-based method to synthesize substrate-bound Au nanowires. By tuning the molecular ligands used during the synthesis, the Au nanowires can be grown from various substrates with different surface properties. Au nanowire-based nanostructures can also be synthesized by adjusting the reaction parameters.