私たちは、財政支援のためのLindback財団、博士アレクサンダー·シドレンコとエルザチュー実り議論や技術支援のために、そしてCと支援のための教授のロバート·スミスに感謝虫アッセイ 。

注：以下の手順では、実験室の安全ガイドラインは、必ず従わなければなりません。特に重要なのは、高電圧（&gt; 500 V）および取り扱い化学物質を扱う安全である。 キャンドルすすと導電性基板の1.コーティング<ol><li>長方形に切断の銅金属（0.5mm厚75×43ミリメートル）。約20秒間水道水で洗って、約30秒間銅エッチング液に浸漬することにより、各銅基板をきれいにし、紙で乾燥させます。 注：以下の方法1を使用する場合は、マシンに収まるように75×25 mmの寸法を変更します。 </li><li>ほぼ均一なすすコーティングを得るために、30〜45秒間、銅基板の下に点灯してパラフィンろうそくをスイープ（約40μm厚）。火炎内部〜1センチメートルで基板を保管してください。脆弱なすす面に触れないでください。 </li></ol> 2.コーティングでスート層の保護注：スート層は非常に脆弱である、および保護のために被覆しなければならない。つの単純な代替案（メソッド1及び2）は、ここで提案されているが、より堅牢なプロトコルが現在開発中である。 <ol><li>方法1 <ol><li>金属蒸発器またはスパッタリング装置内に試料をロードします。システムの操作手順に従って、チャンバを排気し、スート層（150〜200ナノメートル）の上に金の制御された堆積を開始します。デバイスは、室温まで冷却してみましょう。 </li><li>化学フード内部10分間1-ドデカンチオール溶液（1％v / v、95％エタノール中で、ACS / USPグレード）、ディップコート金属化基板。その後、60°に近い角度でデバイスを保持し、静かにエタノールのみの数滴で表面を洗う。一晩、デバイスは、乾燥してみましょう。 </li></ol></li><li>方法2 <ol><li>基板はまだろうそくの炎から温かいうちに化学フード内で、すぐに煤を基板上に塗布した後、のいずれかの側にフッ素化された液体の一部の液滴を堆積し基板、および90°に近い角度に基板を傾けます。より多くの液滴を堆積し、それらが全体のすす表面上を転がるましょう。 注：液滴がスポットに当たるときは、煤がその領域から洗い流される。フッ素化された液体の液滴の広がりを可能な限りう。 </li><li>化学フード内部のホットプレート（15分間160℃）上の基板焼く。 </li><li>基板は、使用前に室温で一晩放置します。無期限に保管してください。 </li></ol></li></ol> 3.上部電極の作製（Abdelgawad らから適応。12） <ol><li>グラフィックデザインソフトウェアを使用して電極を描画します。各電極は、幅0.3mm、長さ2mmであり、電極間のギャップは0.3mmである。接点（下記参照、コネクタにスナップするため）との間のギャップは2.3ミリメートルです（ 図1）。 </li><li>モナーク形式に柔軟な銅積層（厚さ35μm）（3.87×7.5インチ）トリム。他のサイズを使用してIプリンタと互換性fを。カラープリンタの手差しトレイに積層体をロードします。 </li><li>銅板に印刷する場合、エッチング中に印刷されたパターンを保護する、銅基板上のブラックインクの密度の高い層を可能にするために「リッチブラック」、または「登録黒&quot;を使用してください（詳細についてはAbdelgawad ら 12を参照）ことを確認してください。プリント基板に完全に乾燥させ、一晩。 </li><li>化学フード内では、（40°C）、銅エッチング液を50 mlのビーカーを温める。ビーカー内の印刷された積層体を浸し、ゆっくり約10分間溶液中にそれを振る。エッチング時間は、銅エッチング溶液によって異なります。数分ごとには、腐食を確認し、パターンが無傷であるかどうかを確認。 </li><li>慎重に水で積層体を洗って、化学フード内でアセトン、エタノールでコーティングを除去。もう一度洗って、優しくペーパータオルで積層体を乾燥させます。 </li><li>慎重にGLAに電極を積層板を取り付けるSSスライド（75×25ミリメートル、厚さの〜1ミリメートル）、両面テープを使用した。エアポケットを避けてください。 </li><li>テープを使用して、電極にパーフルオロアルコキシPFAのフィルムを取り付けます。これは、液滴と電極の偶発的な接触を防止するのに役立つによる短絡の損傷上部電極。 </li></ol> 4.（図2の回路）電子インターフェース<ol><li>ユニバーサル回路基板にリレーやコンデンサCを半田付けします。 </li><li>電子回路用のブレッドボード上で10のリレードライバの残りの部分を組み立てます。 </li><li>各ワイヤは、制御基板内のチャネルに、運転者の入力をリレー。 </li><li>慎重にコネクタ（ 図3）に上部電極をスナップ。図に示すように、ワイヤそれぞれは、上部電極にドライバの出力を中継する。電気ノイズを最小化するために、リレーからの一対のワイヤ間に接地されたコネクタ接点があることに留意されたい。 注：コネクターは、Tを制御するために調節可能なプラットフォーム上に座っ彼は距離頂部と底部との間（0.1〜0.5ミリメートル）（スートコーティングされた）基板。 </li><li>その後2345年、3456 など ; 0.8秒、作動させるために1234年、すなわち運動（の方向に1電極をずらし、同時に4電極に高電圧（HV）アプリケーション（約0.8秒）のタイミングを制御するプログラムを使用してください。0.8グループごとに秒、その後、後方に、反対方向に移動するので、液滴も同様）。 </li></ol> 5.液滴可視化と取扱い<ol><li> CCDカメラと組み合わせ96X倍率アセンブリ - 液滴の動きを記録するために、24Xで構成されている可視化システムを使用する。 Sビデオを使用してカメラにビデオレコーダーを接続します。 </li><li> Cを含む4μlの滴をピペットですす被覆基板の底部にあるメディアでエレガンス 。 </li><li>液滴上記〜0.3ミリメートルに上部電極を持参してください。液滴がより簡単に操作のための、ちょうど第五電極直下の、真ん中に近くなければなりません。 </li><li>電子インターフェースと高電圧（500 V RMS）の電源をオンにし、それが移動を開始するまでの液滴に上部電極の距離を調整する。上部電極は、液滴を接触させてはいけません。 </li><li>電気パルスに応答したデバイス上で成功した液滴転送回数を記録することによって、データを収集する。成功した実験は、少なくとも700滴転送、 すなわち 、各電気パルスの後1転送することを特徴とする。 </li><li>滴が5から10パルスに応答して、もはや動かないまで、継続的にデータを収集する。 注：表面が劣化し始めると、動きが近い液滴に上部電極にすることによって回復することができた。 </li></ol>

<ol>
	<li>Fair, R. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Digital+microfluidics:+is+a+true+lab-on-a-chip+possible.">Digital microfluidics: is a true lab-on-a-chip possible.</a> Microfluid Nanofluid. 3 (3), 245-281 (2007).</li><li>Gupta, S., Alargova, R. G., Kilpatrick, P. K., Velev, O. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On-Chip+Dielectrophoretic+Coassembly+of+Live+Cells+and+Particles+into+Responsive+Biomaterials.">On-Chip Dielectrophoretic Coassembly of Live Cells and Particles into Responsive Biomaterials.</a> Langmuir. 26 (5), 3441-3452 (2009).</li><li>Shih, S. 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The authors declare that they have no competing financial interests.

プロトコルの最も重要なステップは、直接、液滴を動かすの成功に関連付けられている、スート層の保護である。スート層（上記の方法1）を金属化することは、製造の成功の100％に近いことができる。しかし、最大動作時間は約10分である。おそらく、小滴のフラクションは、金属層の貫通孔煤湿潤される。フッ素化液体とのスート層をコーティングすることは、最も簡単かつ最速の代替で?...

液体を扱う装置の小型化は、「ラボオンチップ」のプラットフォームの開発のために最も重要である。この方向では、最後の二十年は、様々なアプリケーションで、マイクロフルイディクスの分野で大きな進歩を目撃した。1-5同封チャンネル（チャンネルマイクロフルイディクス）内の流体の輸送に対照的な、DMFは、電極のアレイ上の液滴を操作する。この技術の最も魅力的なメリットの一つは、流体を輸送するための可動部がないことで、動きを瞬時に電気信号をオフにすることによって停止される。 しかし、液滴の運動は、液滴の内容、ユニバーサル」ラボオンチップ」プラットフォームの確かに望ましくない特性に依存する。タンパク質や他の検体を含む液滴が移動不能になって、デバイス表面に固執する。間違いなく、これをDMFアプリケーションの適用範囲を広げるための主要な制限されている; 6-8不要な表面の汚れを最小にする選択肢は、潜在的に液滴コンテンツに影響を与える可能性が液滴またはその周囲に余分な化学種の添加を含む。 以前、我々のグループは、追加の添加剤（電界DW装置）なしで、DMF中の細胞およびタンパク質の輸送を可能にする装置を開発し9これは、液滴圧延を優先するデバイス·ジオメトリを有するキャンドルすす、10に基づいて、面を組み合わせることによって達成されたさらに、液滴表面相互作用を減少させる、液滴に上向きの力をもたらす。このアプローチでは、液滴の運動は、表面の濡れに関連付けられていない。11 以下に説明する詳細な方法の目的は、余分な添加剤を含まない、タンパク質、細胞、および生物全体を含む液滴を輸送することができるDMFデバイスを製造することである。フィールド-DWデバイスは、大部分が独立して液滴化学者の作業完全に制御プラットフォームへの道を開くRY。 ここでは、それを示す、本シミュレーションでは、デバイスの動作に必要な高電圧にもかかわらず、液滴の両端の電圧降下は、液滴内部bioanalytesにほとんど影響を示し、印加電圧のごく一部である。実際には、 線虫（C.エレガンス ）、生物学の研究のさまざまな目的で使用線虫を用いた予備試験では、電圧が印加されるとワームが乱さ泳ぐことを示している。

<table border="0" cellpadding="0" cellspacing="0" width="1230">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Name of Material/ Equipment</td>
			<td style="width:119px;">Company</td>
			<td style="width:161px;">Catalog Number</td>
			<td style="width:720px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Paraffin candle</td>
			<td style="width:119px;"></td>
			<td style="width:161px;"></td>
			<td>Any paraffin candle</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">Sputtering system</td>
			<td style="width:119px;">Denton Vacuum, Moorestown, NJ</td>
			<td style="width:161px;"></td>
			<td>Sputter coater Desk V HP equipped with an Au target.&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">1-dodecanethiol</td>
			<td style="width:119px;">Sigma-Aldrich</td>
			<td align="right" style="width:161px;">471364</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Teflon</td>
			<td style="width:119px;">Dupont</td>
			<td style="width:161px;">AF-1600</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Fluorinert FC-40</td>
			<td style="width:119px;">Sigma-Aldrich</td>
			<td style="width:161px;">F9755</td>
			<td>Fluorinated liquid: Prepare Teflon-AF resin in Fluorinert FC-40, 1:100 (w/w), to create the hydrophobic coating.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">Graphic design software -Adobe Illustrator</td>
			<td style="width:119px;">Adobe Systems</td>
			<td style="width:161px;"></td>
			<td>Other softwares might be used as well.</td>
		</tr>
		<tr height="18">
			<td height="18" style="height:18px;width:231px;">Copper laminate</td>
			<td style="width:119px;">Dupont</td>
			<td style="width:161px;">LF9110</td>
			<td></td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:231px;">Laser Printer</td>
			<td style="width:119px;">Xerox</td>
			<td style="width:161px;">Phaser 6360 or similar</td>
			<td>Check for the compatibility with &#34;rich black&#34; or &#34;registration black&#34; (see text).</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Copper Etchant</td>
			<td style="width:119px;">Transene</td>
			<td style="width:161px;">CE-100</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Perfluoroalkoxy (PFA) film</td>
			<td style="width:119px;">McMaster-Carr</td>
			<td style="width:161px;">84955K22</td>
			<td></td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:231px;">Breadboard</td>
			<td style="width:119px;">Allied Electronics</td>
			<td style="width:161px;">70012450 or similar</td>
			<td>Large enough to allow the assemble of 10 drivers.</td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:231px;">Universal circuit board</td>
			<td style="width:119px;">Allied Electronics</td>
			<td style="width:161px;">70219535 or similar</td>
			<td></td>
		</tr>
		<tr height="28">
			<td height="28" style="height:28px;width:231px;">Connector</td>
			<td style="width:119px;">Allied Electronics</td>
			<td style="width:161px;">5145154-8 or similar</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">Control board and control program (LabView software)</td>
			<td style="width:119px;">National Instruments</td>
			<td style="width:161px;">NI-6229 or similar</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">High-voltage amplifier</td>
			<td style="width:119px;">Trek</td>
			<td style="width:161px;">PZD700</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Resistor R 27 k&#8486;, 1/4 W</td>
			<td style="width:119px;">Allied&#160;</td>
			<td align="right" style="width:161px;">2964762</td>
			<td></td>
		</tr>
		<tr height="27">
			<td height="27" style="height:27px;width:231px;">Capacitors C and C1, 100 nF, 60 V</td>
			<td style="width:119px;">Allied&#160;</td>
			<td align="right" style="width:161px;">8817183</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Transistor T, NPN</td>
			<td style="width:119px;">Allied&#160;</td>
			<td align="right" style="width:161px;">9350289</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Diode D, 1N4007</td>
			<td style="width:119px;">Allied&#160;</td>
			<td align="right" style="width:161px;">2660007</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Relay&#160;</td>
			<td style="width:119px;">Allied&#160;</td>
			<td align="right" style="width:161px;">8862527</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:231px;">Visualization system</td>
			<td style="width:119px;">Edmund Optics</td>
			<td style="width:161px;">VZM 200i or similar</td>
			<td>System magnification 24X- 96X. It is combined with a Hitachi KP-D20B 1/2 in CCD Color Camera.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">Recorder</td>
			<td style="width:119px;">Sony</td>
			<td style="width:161px;">GV-D1000 NTSC or similar</td>
			<td>It is connected to the camera by an S-video cable.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:231px;">Simulations</td>
			<td style="width:119px;">COMSOL Multiphysics</td>
			<td style="width:161px;">V. 4.4</td>
			<td></td>
		</tr>
	</tbody>
</table>

taking advantage of reduced droplet-surface interaction to optimize transport of bioanalytes in digital microfluidics

Digital microfluidics (DMF), a technique for manipulation of droplets, is a promising alternative for the development of &#8220;lab-on-a-chip&#8221; platforms. Often, droplet motion relies on the wetting of a surface, directly associated with the application of an electric field; surface interactions, however, make motion dependent on droplet contents, limiting the breadth of applications of the technique.
Some alternatives have been presented to minimize this dependence. However, they rely on the addition of extra chemical species to the droplet or its surroundings, which could potentially interact with droplet moieties. Addressing this challenge, our group recently developed Field-DW devices to allow the transport of cells and proteins in DMF, without extra additives.
Here, the protocol for device fabrication and operation is provided, including the electronic interface for motion control. We also continue the studies with the devices, showing that multicellular, relatively large, model organisms can also be transported, arguably unaffected by the electric fields required for device operation.

以前、我々は、DMF中のタンパク質の運動を可能にするためにフィールド-DWデバイスを使用している。特に、ウシ血清アルブミン（BSA）を有する液滴が以前に（添加剤なし）、他の著者によって報告されたものより2000倍高い濃度で移動することができる。これは滴と表面との間の相互作用の減少によるものであった; 図4は、蛍光標識したBSAを（。フレイレら参照実験?...

Watch this Scientific Journal Video about Taking Advantage of Reduced Droplet-surface Interaction to Optimize Transport of Bioanalytes in Digital Microfluidics at JoVE.com

Taking Advantage of Reduced Droplet-surface Interaction to Optimize Transport of Bioanalytes in Digital Microfluidics

The protocol for fabrication and operation of field dewetting devices (Field-DW) is described, as well as the preliminary studies of the effects of electric fields on droplet contents.

デジタルマイクロフルイディクスにBioanalytesの輸送を最適化するための縮小液滴表面相互作用の活用

Digital microfluidics (DMF), a technique for manipulation of droplets, is a promising alternative for the development of &#8220;lab-on-a-chip&#8221; ...

taking-advantage-reduced-droplet-surface-interaction-to-optimize

Research

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Electrical Engineering

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Unit 1

The Laplace Transform

SCIENTISTS IN ACTION

7.8K ビュー.  University of the Sciences. The protocol for fabrication and operation of field dewetting devices (Field-DW) is described, as well as the preliminary studies of the effects of electric fields on droplet contents.

ビデオ: Taking Advantage of Reduced Droplet-surface Interaction to Optimize Transport of Bioanalytes in Digital Microfluidics

Evaluating Plasmonic Transport in Current-carrying Silver Nanowires

Plasmonics is an emerging technology capable of simultaneously transporting a plasmonic signal and an electronic signal on the same information support1,2,3. In this context, metal nanowires are especially desirable for realizing dense routing networks4. A prerequisite to operate such shared nanowire-based platform relies on our ability to electrically contact individual metal nanowires and efficiently excite surface plasmon polaritons5 in this information support. In this article, we describe a protocol to bring electrical terminals to chemically-synthesized silver nanowires6 randomly distributed on a glass substrate7. The positions of the nanowire ends with respect to predefined landmarks are precisely located using standard optical transmission microscopy before encapsulation in an electron-sensitive resist. Trenches representing the electrode layout are subsequently designed by electron-beam lithography. Metal electrodes are then fabricated by thermally evaporating a Cr/Au layer followed by a chemical lift-off. The contacted silver nanowires are finally transferred to a leakage radiation microscope for surface plasmon excitation and characterization8,9. Surface plasmons are launched in the nanowires by focusing a near infrared laser beam on a diffraction-limited spot overlapping one nanowire extremity5,9. For sufficiently large nanowires, the surface plasmon mode leaks into the glass substrate9,10. This leakage radiation is readily detected, imaged, and analyzed in the different conjugate planes in leakage radiation microscopy9,11. The electrical terminals do not affect the plasmon propagation. However, a current-induced morphological deterioration of the nanowire drastically degrades the flow of surface plasmons. The combination of surface plasmon leakage radiation microscopy with a simultaneous analysis of the nanowire electrical transport characteristics reveals the intrinsic limitations of such plasmonic circuitry.

Silver nanowires can simultaneously transport electrons and optical information in the form of surface plasmons. A procedure is described here to realize such a shared circuitry and the limitations at propagating both information carriers are evaluated.

Plasmonics is an emerging technology capable of simultaneously transporting a plasmonic signal and an electronic signal on the same information ...

工学

Characterization of Thermal Transport in One-dimensional Solid Materials

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials, including conductive, semi-conductive or nonconductive one-dimensional structures. This technique broadens the measurement scope of materials (conductive and nonconductive) and improves the accuracy and stability. If the sample (especially biomaterials, such as human head hair, spider silk, and silkworm silk) is not conductive, it will be coated with a gold layer to make it electronically conductive. The effect of parasitic conduction and radiative losses on the thermal diffusivity can be subtracted during data processing. Then the real thermal conductivity can be calculated with the given value of volume-based specific heat (&#961;cp), which can be obtained from calibration, noncontact photo-thermal technique or measuring the density and specific heat separately. In this work, human head hair samples are used to show how to set up the experiment, process the experimental data, and subtract the effect of parasitic conduction and radiative losses.

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials.

一次元固体材料の熱輸送のキャラクタリゼーション

The TET (transient electro-thermal) technique is an effective approach developed to measure the thermal diffusivity of solid materials, including ...

Real-Time DC-dynamic Biasing Method for Switching Time Improvement in Severely Underdamped Fringing-field Electrostatic MEMS Actuators

Mechanically underdamped electrostatic fringing-field MEMS actuators are well known for their fast switching operation in response to a unit step input bias voltage. However, the tradeoff for the improved switching performance is a relatively long settling time to reach each gap height in response to various applied voltages. Transient applied bias waveforms are employed to facilitate reduced switching times for electrostatic fringing-field MEMS actuators with high mechanical quality factors. Removing the underlying substrate of the fringing-field actuator creates the low mechanical damping environment necessary to effectively test the concept. The removal of the underlying substrate also a has substantial improvement on the reliability performance of the device in regards to failure due to stiction. Although DC-dynamic biasing is useful in improving settling time, the required slew rates for typical MEMS devices may place aggressive requirements on the charge pumps for fully-integrated on-chip designs. Additionally, there may be challenges integrating the substrate removal step into the back-end-of-line commercial CMOS processing steps. Experimental validation of fabricated actuators demonstrates an improvement of 50x in switching time when compared to conventional step biasing results. Compared to theoretical calculations, the experimental results are in good agreement.

The robust device design of fringing-field electrostatic MEMS actuators results in inherently low squeeze-film damping conditions and long settling times when performing switching operations using conventional step biasing. Real-time switching time improvement with DC-dynamic waveforms reduces the settling time of fringing-field MEMS actuators when transitioning between up-to-down and down-to-up states.

重度不足減衰フリンジフィールド静電MEMSアクチュエータに時間改善スイッチング用リアルタイムDC-ダイナミックバイアス方式

Mechanically underdamped electrostatic fringing-field MEMS actuators are well known for their fast switching operation in response to a unit step input ...

How to Build a Vacuum Spring-transport Package for Spinning Rotor Gauges

The spinning rotor gauge (SRG) is a high-vacuum gauge often used as a secondary or transfer standard for vacuum pressures in the range of 1.0 x 10-4 Pa to 1.0 Pa. In this application, the SRGs are frequently transported to laboratories for calibration. Events can occur during transportation that change the rotor surface conditions, thus changing the calibration factor. To assure calibration stability, a spring-transport mechanism is often used to immobilize the rotor and keep it under vacuum during transport. It is also important to transport the spring-transport mechanism using packaging designed to minimize the risk of damage during shipping. In this manuscript, a detailed description is given on how to build a robust spring-transport mechanism and shipping container. Together these form a spring-transport package. The spring-transport package design was tested using drop-tests and the performance was found to be excellent. The present spring-transport mechanism design keeps the rotor immobilized when experiencing shocks of several hundred g (g = 9.8 m/sec2 and is the acceleration due to gravity), while the shipping container assures that the mechanism will not experience shocks greater than about 100 g during common shipping mishaps (as defined by industry standards).

Here we describe how to build a robust spring-transport mechanism for a spinning rotor gauge. This device securely immobilizes the rotor and keeps it under vacuum during transportation. We also describe packaging that minimizes the risk of damage during transport. Tests show our design works for typical shocks during transport.

どのようにローターゲージをスピニングするための真空春輸送パッケージをビルドするには

The spinning rotor gauge (SRG) is a high-vacuum gauge often used as a secondary or transfer standard for vacuum pressures in the range of 1.0 x 10-4 Pa to ...

Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less environmentally damaging with lower processing temperatures presenting a viable and low cost alternative to conventional production. This paper further enhances these environmental credentials by evaluating the digital printing and therefore additive production route for these cells. This is achieved here by investigating the formation and performance of a metal oxide photoelectrode using nanoparticle sized titanium dioxide. An ink-jettable material was formulated, characterized and printed with a piezoelectric inkjet head to produce a 2.6 &#181;m thick layer. The resultant printed layer was fabricated into a functioning cell with an active area of 0.25 cm2 and a power conversion efficiency of 3.5%. The binder-free formulation resulted in a reduced processing temperature of 250 &#176;C, compatible with flexible polyamide substrates which are stable up to temperatures of 350 &#730;C. The authors are continuing to develop this process route by investigating inkjet printing of other layers within dye sensitized solar cells.

This paper investigates the suitability of inkjet printing for the manufacturing of dye-sensitized solar cells. A binder-free TiO2 nanoparticle ink was formulated and printed onto a FTO glass substrate. The printed layer was fabricated into a cell with an active area of 0.25 cm2 and an efficiency of 3.5%.

色素増感太陽電池用二酸化チタンのデジタル印刷

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less ...

Ultrasonic Fatigue Testing in the Tension-Compression Mode

Ultrasonic fatigue testing is one of a few methods which allow investigating fatigue properties in the ultra-high cycle region. The method is based on exposing the specimen to longitudinal vibrations on its resonance frequency close to 20 kHz. With use of this method, it is possible to significantly decrease the time required for the test, when compared to conventional testing devices usually working at frequencies under 200 Hz. It is also used to simulate loading of material during operation in high speed conditions, such as those experienced by components of jet engines or car turbo pumps. It is necessary to operate only in the high and ultra-high cycle region, due to the possibility of extremely high deformation rates, which can have a significant influence on the test results. Specimen shape and dimensions have to be carefully selected and calculated to fulfill the resonance condition of the ultrasonic system; thus, it is not possible to test the full components or specimens of arbitrary shape. Before each test, it is necessary to harmonize the specimen with the frequency of the ultrasonic system to compensate for deviations of the real shape from the ideal one. It is not possible to run a test until a total fracture of the specimen, since the test is automatically terminated after initiation and propagation of the crack to a certain length, when the stiffness of the system changes enough to shift the system out of the resonance frequency. This manuscript describes the process of evaluation of materials' fatigue properties at high-frequency ultrasonic fatigue loading with use of mechanical resonance at a frequency close to 20 kHz. The protocol includes a detailed description of all steps required for a correct test, including specimen design, stress calculation, harmonizing with the resonance frequency, performing the test, and final static fracture.

A protocol for ultrasonic fatigue testing in the high and ultra-high cycle region in axial tension-compression loading mode.

超音波疲労引張圧縮モードでのテスト

Ultrasonic fatigue testing is one of a few methods which allow investigating fatigue properties in the ultra-high cycle region. The method is based on ...

Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions

The microstructure of soft matter directly impacts macroscopic rheological properties and can be changed by factors including colloidal rearrangement during previous phase changes and applied shear. To determine the extent of these changes, we have developed a microfluidic device that enables repeated phase transitions induced by exchange of the surrounding fluid and microrheological characterization while limiting shear on the sample. This technique is &#181;2rheology, the combination of microfluidics and microrheology. The microfluidic device is a two-layer design with symmetric inlet streams entering a sample chamber that traps the gel sample in place during fluid exchange. Suction can be applied far away from the sample chamber to pull fluids into the sample chamber. Material rheological properties are characterized using multiple particle tracking microrheology (MPT). In MPT, fluorescent probe particles are embedded into the material and the Brownian motion of the probes is recorded using video microscopy. The movement of the particles is tracked and the mean-squared displacement (MSD) is calculated. The MSD is related to macroscopic rheological properties, using the Generalized Stokes-Einstein Relation. The phase of the material is identified by comparison to the critical relaxation exponent, determined using time-cure superposition. Measurements of a fibrous colloidal gel illustrate the utility of the technique. This gel has a delicate structure that can be irreversibly changed when shear is applied. &#181;2rheology data shows that the material repeatedly equilibrates to the same rheological properties after each phase transition, indicating that phase transitions do not play a role in microstructural changes. To determine the role of shear, samples can be sheared prior to injection into our microfluidic device. &#181;2rheology is a widely applicable technique for the characterization of soft matter enabling the determination of rheological properties of delicate microstructures in a single sample during phase transitions in response to repeated changes in the surrounding environmental conditions.

We demonstrate the fabrication and use of a microfluidic device that enables multiple particle tracking microrheology measurements to study the rheological effects of repeated phase transitions on soft matter.

繰り返し相転移の間に柔らかい物質のレオロジー的性質を決定するためのマイクロ流体システムとレオロジーを組み合わせること

The microstructure of soft matter directly impacts macroscopic rheological properties and can be changed by factors including colloidal rearrangement ...

Fabrication of Refractive-index-matched Devices for Biomedical Microfluidics

The use of microfluidic devices has emerged as a defining tool for biomedical applications. When combined with modern microscopy techniques, these devices can be implemented as part of a robust platform capable of making simultaneous complementary measurements. The primary challenge created by the combination of these two techniques is the mismatch in refractive index between the materials traditionally used to make microfluidic devices and the aqueous solutions typically used in biomedicine. This mismatch can create optical artifacts near the channel or device edges. One solution is to reduce the refractive index of the material used to fabricate the device by using a fluorinated polymer such as MY133-V2000 whose refractive index is similar to that of water (n = 1.33). Here, the construction of a microfluidic device made out of MY133-V2000 using soft lithography techniques is demonstrated, using O2 plasma in conjunction with an acrylic holder to increase the adhesion between the MY133-V2000 fabricated device and the polydimethylsiloxane (PDMS) substrate. The device is then tested by incubating it filled with cell culture media for 24 h to demonstrate the ability of the device to maintain cell culture conditions during the course of a typical imaging experiment. Finally, quantitative phase microscopy (QPM) is used to measure the distribution of mass within the live adherent cells in the microchannel. This way, the increased precision, enabled by fabricating the device from a low index of refraction polymer such as MY133-V2000 in lieu of traditional soft lithography materials such as PDMS, is demonstrated. Overall, this approach for fabricating microfluidic devices can be readily integrated into existing soft lithography workflows in order to reduce optical artifacts and increase measurement precision.

This protocol describes the fabrication of microfluidic devices from MY133-V2000 to eliminate artifacts that often arise in microchannels due to the mismatching refractive indices between microchannel structures and an aqueous solution. This protocol uses an acrylic holder to compress the encapsulated device, improving adhesion both chemically and mechanically.

生体の屈折率-屈折率整合素子の作製

The use of microfluidic devices has emerged as a defining tool for biomedical applications. When combined with modern microscopy techniques, these devices ...

Crack Monitoring in Resonance Fatigue Testing of Welded Specimens Using Digital Image Correlation

A procedure using digital image correlation (DIC) to detect cracks on welded specimens during fatigue tests on resonance testing machines is presented. It is intended as a practical and reproducible procedure to identify macroscopic cracks at an early stage and monitor crack propagation during fatigue tests. It consists of strain field measurements at the weld using DIC. Images are taken at fixed load cycle intervals. Cracks become visible in the computed strain field as elevated strains. This way, the whole width of a small-scale specimen can be monitored to detect where and when a crack initiates. Subsequently, it is possible to monitor the development of the crack length. Because the resulting images are saved, the results are verifiable and comparable. The procedure is limited to cracks initiating at the surface and is intended for fatigue tests under laboratory conditions. By visualizing the crack, the presented procedure allows direct observation of macrocracks from their formation until rupture of the specimen.

Digital image correlation is used in fatigue tests on a resonance testing machine to detect macroscopic cracks and monitor crack propagation in welded specimens. Cracks on the specimen surface become visible as increased strains.

デジタル画像相関を用いた溶接試料の共振疲労試験における亀裂モニタリング

A procedure using digital image correlation (DIC) to detect cracks on welded specimens during fatigue tests on resonance testing machines is presented. It ...

Automated Delivery of Microfabricated Targets for Intense Laser Irradiation Experiments

Described is an experimental procedure that enables high-power laser irradiation of microfabricated targets. Targets are brought to the laser focus by a closed feedback loop that operates between the target manipulator and a ranging sensor. The target fabrication process is explained in detail. Representative results of MeV-level proton beams generated by irradiation of 600 nm thick gold foils at a rate of 0.2 Hz are given. The method is compared with other replenishable target systems and the prospects of increasing the shot rates to above 10 Hz are discussed.

A protocol is presented for automated irradiation of thin gold foils with high intensity laser pulses. The protocol includes a step-by-step description of the micromachining target fabrication process and a detailed guide for how targets are brought to the laser&#39;s focus at a rate of 0.2 Hz.

激しいレーザー照射実験のためのマイクロ加工対象の自動送達

Described is an experimental procedure that enables high-power laser irradiation of microfabricated targets. Targets are brought to the laser focus by a ...