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

植物フェノール由来のポリマー染料の調製<ol><li> 100 mM酢酸ナトリウム緩衝液（pH 5.0）および無水エタノール8mlの32 ml中カテキン水和物（0.1g）を - カテコール（0.1 g）およびを（+）に溶解します。 </li><li> T. 10mgを追加します。 catechol-とカテキン含有緩衝液にversicolorのラッカーゼ 。激しく混合し、正方形のペトリ皿にソリューションを注ぎます。 24時間振盪インキュベーター（25回転）で、室温で皿をインキュベートします。濃い黒色の透明な溶液からの劇的な色の変化は、ラッカーゼによって誘導されるカップリング反応の後に肉眼で観察することができます。 </li><li>不溶性ポリマー粒子をスピンダウンするために20,000×gで10分間この溶液を遠心分離します。さらに脱塩のための深い黒の上清を使用してください。 </li><li> 5 kDaの限外濾過ディスクとの反応液を脱塩。限外20〜mlまで反応容量を濃縮した後、蒸留水300mlを加えて反応緩衝液を交換し。最後に、濾過を用いて25 mlに溶液の体積を濃縮。 </li></ol>グレーケラチン髪2.染色ソリューション<ol><li>ポリマー染料、ポリマー染料/のFeSO 4、pHが3水中でのポリマー染料/のFeSO 4、pHが11水、酢酸によるポリマー染料/のFeSO 4、及びポリマー染料/のFeSO中のポリマー染料/のFeSO 4：以下の6つのポリマー溶液を準備しますアンモニアと4。 <ol><li>ポリマー色素については、脱塩ポリマー染料（1.4）1mlと5mlの蒸留水を混ぜます。 </li><li>媒染剤のソリューションについては、ステップ2.1.1から混合物へのFeSO 4の0.33グラムを追加します。激しくボルテックス完全のFeSO 4を溶解しました。 </li><li> pHが3または11水溶液のために、1 N HCl又は1NのNaOHを用いて水を5mlの蒸留液のpHを調整します。その後、脱塩ポリマー染料（1.4）の1ミリリットルとのFeSO 4の0.33グラムを追加します。 </li><li>酢酸酸やアンモニア処理液については、GLの1.0ミリリットルを混ぜますacial酢酸または蒸留水5mlとアンモニア水1.0 mlです。その後、脱塩ポリマー染料（1.4）の1ミリリットルとのFeSO 4の0.33グラムを追加します。 </li></ol></li><li>に髪を浸して、のFeSO 4の0.33グラムの有無にかかわらず、蒸留水6mlにカテキン水和物（0.1グラム） -植物モノマーについては、カテコールを（0.1グラム）および（+）混ぜます。 </li><li>すぐにステップ2.1および2.2からの染色溶液を調製しているように、完全に溶液中で5センチ長い灰色の人間の髪の毛の房（0.2グラム）を浸します。 2.5時間振盪インキュベーターで32°C（160 rpm）で髪の房をインキュベートします。 </li><li>その後、毛髪束を取り出し、流水でそれらを洗い流してください。水分を除去するために、電子ヘアドライヤーを使用してください。ポリマー色素による色変化は、肉眼で可視化することができます。 <ol><li>色パラメータ（ すなわち、L *、a *及びb *）を得るために、製造業者のプロトコルに従って、従来の比色計を使用します。髪トンをくしゃくしゃこうして彼らは測色計のレンズを用いて測定することができるように、ボールにresses。測色計レンズで髪の異なる地域にこのプロセスを繰り返します。 </li><li>各染色したトレス7倍の色パラメータを測定します。平均値とパラメータの標準偏差を計算します。式を用いてΔEを計算する：[（100 - のL *）2 +（*）2 +（B *）2] 1/2。 </li></ol></li></ol> 3.色耐久試験<ol><li>蒸留水40mlにドデシル硫酸ナトリウム（SDS）を200mg溶解させます。室温で5分間SDSを含む水の中に完全に染めた髪を浸します。髪の房を取り出し、その後、洗剤を除去するのに十分な流水でそれらを洗い流してください。水分を除去するために、電子ヘアドライヤーを使用してください。 </li><li>色パラメータ（ すなわち、L *、a *及びb *）を得るために、機械製造に記載の従来の比色計を使用えーのプロトコル。同じ染めた髪でもう一度ステップ3.1で説明した浸漬を繰り返してから、再度パラメータを測定します。 </li><li>蒸留水40mlにSDSの800ミリグラムを溶解します。ステップ3.1で説明したように、同じ染めた髪で二回以上浸漬を繰り返します。全体的に、SDS溶液で4回の合計を各染め毛束を扱います。 </li></ol>

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The authors declare that they have no competing financial interests.

興味深いことに、我々の方法は、それが自然なフェノールの酸化剤によって誘発される重合でケラチン髪を染めるためにかかった時間を減少させました。それはまた、pHを変えると媒染剤を適用するなどの高分子染料の簡単な操作を通じて、髪に多様な色を誘導しました。 植物フェノールのラッカーゼ触媒酸化とケラチン髪のその場でのインキュベーションで?...

ラッカーゼは、フェノール及びポリフェノール化合物に対して活性であるオキシダーゼです。それらは、植物、真菌、昆虫、および細菌を含む様々な生物において同定されています。その酵素のアクションは、いくつかの形態形成現象1に貢献しています。酵素はさらに小さな有機物を、固体表面に結合されているラジカルの形成をもたらす、基板の一電子酸化を触媒します。このようなカップリングプロセスは、オリゴマーおよびポリマーの合成につながり、官能基化2、3を表面化。ラッカーゼの基質は、植物フェノール成分として天然源、からのものである場合には、酵素反応は、グリーンケミストリーに関して非常に興味深いです。ここでは、両方の反応物及び触媒は、天然源からのものです。全体的な反応は、植物のリグニン、ポリ（flavono天然フェノール-含むポリマーのインビボ合成を模倣するために加えて、得られた生成物は、天然物に類似していますID）、および腐植、前記小植物フェノール化合物は、高度に架橋されたオキシダーゼによって誘導されるラジカルカップリング4です。 植物由来のフェノールのラッカーゼ触媒カップリング反応に由来する生成物は、 その場でのインキュベーションで白髪を介して染色するために使用することができ、市販の染料1の代替として開発することができます。商業的毛髪染色剤は、毒性発癌性、およびヒト5,6にアレルギー性であることが示されているのpフェニレンジアミン（PPD）、PPD関連のジアミン化合物、過酸化水素、に基づいているので、そのような代替案は、重要である。でラッカーゼ触媒カップリング反応、ラッカーゼ及び植物フェノール類は、機能的には、それぞれ7、過酸化水素およびpフェニレンジアミンを交換してください。しかしながら、ラッカーゼベースのシステムの染色速度が商用のものよりはるかに遅いです。一般に、PPDベースの染色剤は、達成する未満の時間を必要としますケラチン髪に効果的な色の変化、ラッカーゼベースの反応は、一晩のインキュベーション7を必要とします。遅い染色動態は、2つの可能な現象によって説明することができました。まず、低pH緩衝液を使用する（ 例えば、pH 5）ラッカーゼ活性を最大にするためには、このように行列への染料の深い浸透を阻害する、ケラチンマトリックス中での膨潤の程度を低下させることが観察されています。実際、染色反応は、高pH条件で進行させる作用物質は、商業的毛髪染色製品8に不可欠であることが示されています。第二に、重合反応中に角質表面への強い吸着性を示す可能性発色団分子の数は、インキュベーション時間（ すなわち、重合の程度）に比例することが示されています。例えば、ポリドーパミンのドーパミンの変換は、黒色9の形成と同時にた多くの表面に強固な接着を誘導することが示されました。&lt;/ P&gt; 現在の仕事、Tから得た予備合成高分子製品のカテキン及びカテコールのラッカーゼ触媒酸化versicolorの染色のためケラチン髪を治療するために使用しました。我々は、ポリマーの吸着能力は、単量体の植物フェノール類のものよりもはるかに強力であることを、彼らが最初に低分子量のオリゴマーを形成するであろうという仮説を立てました。結果は、事前に合成されたポリマーを使用する場合、酵素的酸化力がもはや必要であったことを実証していません。これは関係なく、酵素活性、pHを制御することができ、その金属イオンは、毛髪染色の治療において使用することができることを示しています。このプロトコルは、環境に優しい再生可能植物由来のフェノール類（ 図1）を使用しながら、色の様々な色合いでケラチン髪を染めるためのシンプルかつ高速な方法を提供します。

<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

植物フェノール類の真菌ラッカーゼ触媒重合の製品とケラチン髪のその場でのインキュベーションの貫通効果的な毛髪染色は、以前に実証されています。しかし、染色工程は、市販の毛染めの製品に比べて完了するまでに長い時間がかかります。このボトルネック、カテキンおよびカテコール上のラッカーゼカワラタケトラメテスの酸化反応の前に合成高分子製品、いずれかの媒染剤剤を伴うまたは伴わない（ 例えば、のFeSO 4）を克服するために、ここでは様々な色や色合いに永久ケラチン染毛を達成するために採用されました。酸性酢酸ナトリウム緩衝液中のラッカーゼのアクションは、植物フェノール類との反応をカップリングした後、深い黒色の着色につながりました。着色された染料生成物は、その後、限外濾過で脱塩し、濃縮しました。媒染剤剤を含むまたは含まない染料は、灰色の人毛のWiにおけるΔE値の有意な増加（ すなわち、色差値）を起し薄い2.5時間。さらに、異なるケラチン色や色合いが媒染およびpH変化に応じて誘導されました。染めた髪はまた、私たちの方法は、永久染毛を生じさせることができることを示す、界面活性剤治療に対する強い抵抗性を示した。全体的に、私たちの仕事は、商用毒性ジアミン系染料の代替として環境に配慮した染毛方法の開発に新たな洞察を提供しています。

まず、ポリマー染料の染着性は、植物由来のモノマー（ すなわち、カテキンおよびカテコール）と比較しました。毛髪の生来のグレー色（ データは示されていない ）植物モノマーと非常に安定したままのポリマー染料は、灰色のケラチン毛髪（ 図2Aおよび図3）の色の有意な変化を誘導しました。ポリマー生成物の染色能...

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.

直接または媒染剤ベースの髪の染色用植物フェノール由来のポリマー染料の合成

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

Research

JoVE Journal

Chemistry

9.2K ビュー.  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.

ビデオ: 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.

官能ナフタレン/ソルバトクロミック色素の合成のためのマイクロ波支援分子内脱水素Diels-Alder反応

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

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.

グリコシダーゼ活性の検出のためのインドキシル配糖体の合成

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.

複雑なアミノグアニジン含有天然物の合成のための直接、早期グアニジニルプロトコル

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.

金ナノロッドのヒドロキノンベースの合成

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.

単一分子レベルでの環状ポリマーの合成と溶融状態におけるそれらの拡散運動のキャラクタリゼーション

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.

組み合わせソリッドステートおよびソリューションベースのテクニック：合成と反応性Chalcogenidoplumbatesの（IIまたは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.

レーザー駆動の超高速分子回転のダイレクトイメージング

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.

コバレント有機骨格（COF）のマイクロ流体ベースの合成：COF繊維の連続生産と表面への直接印刷のためのツール

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.

化学合成チタン酸バリウム多孔質セラミックス薄膜の気孔率誘起歪による強誘電相の熱安定化

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.