이 작품은 고급 냉각 기술에서 미국 국립 과학 재단과 그랜트 번호 117041PO9621에서 그랜트 번호 CBET-0651283에 의해 지원되었다.

1. 실리카의 준비 증착을위한 Nanoparticles <ol><li> 건식 실리카 파우더는 것부터 시작해서, 먼저 대형 집계를 제거하여 코팅을 위해 샘플을 준비합니다. </li><li> 에탄올과 실리카 입자 (젤-TEC 사에서 구입한 200 nm의 직경) (190 증명 순수)를 씻고 에탄올 모든 수분 증발까지 퓸 후드 아래에 샘플을 둡니다. </li><li> 모든 나머지 agglomerations을 깰 수 있도록 금속 meshes 일련의 (미국 # 100-400)을 통해 입자를 엄밀히 조사하다. </li><li> 그림 1에서와 같이 장소 입자와 관형 반응기에 작은 자석 활동가 바,. 입자 플라즈마 영역 안에 배치해야합니다. </li><li> 둘은 유리관의 끝에 하나는 펌프에 연결된 파이프의 끝 부분에 하나, 플랜지 사이에 O-링을 게재하여 유리 반응기를 밀봉합니다. </li><li> 플랜지와 손을 클램프 주위에 나사를 조여 주위의 스테인레스 스틸 클램프 링을 설치합니다. </li></ol> 2.진공 시스템의 준비 <ol><li> 액체 질소 트랩을 채우기 다음, 트랩의 표면 냉정하게 될 수 있습니다. 5 분 정도 기다립니다. </li><li> 버블러에 이소프로판올을 추가하고 플라즈마 반응기에 연결합니다. </li><li> 금속 파이프 주위에 고무 O-링을 배치하여 버블러을 봉쇄하고 버블러 연결로 파이프의 자리까지 너트를 조여 것은 봉인된다. </li></ol> 3. 플라즈마 증착 프로세스 <ol><li> ± 2 ° C. 34 온도로 물을 욕조에 버블러를 배치 </li><li> 아르곤 가스 유량 컨트롤러의 전원을 켜고 세트 포인트와 같은 6.00 sccm를 입력하십시오. </li><li> 점차적으로 펌프가 작동되는 동안 펌프로 유리 튜브를 연결하는 게이트 밸브를 엽니다. 압력의 갑작스런 감소는 입자 흐름에 날아되는 원인이 될 수 있기 때문에 신중하게이 단계를 수행합니다. 압력이 200 mTorr에 도달할 때까지 기다린 후 게이트 밸브를 완전히 열어두고. </li><li> 유리관 아래 자성 활동가를 삽입 및 100 R 속도를 설정시. </li><li> 무선 주파수에 관형 유리 반응기, RF, 발전기 주변 알루미늄 링을 연결하고 그라운드에 스테인리스 스틸 클램프를 연결합니다. </li><li> 매칭 네트워크 AC 라인과에서 RF 발생기 전원을 전환 후 (ENI MW-5D) 먼저 켜십시오. 전체 프로세스 30 W의 전력을 설정합니다. </li><li> 각각 시간 (10, 20, 또는 40 분)과 일치하는 네트워크를 해제, RF 발생기 및 AC 전원의 특정 기간 후에. </li><li> 체크 밸브를 닫고 다음 아르곤 유량 컨트롤러를 해제합니다. 밸브에서 버블러을 분리하고 점차적으로 대기로 원자로 압력을 증가. </li><li> 클램프를 열고 금속 주걱을 사용하여 플라스틱 그릇에 관에서 입자를 전송합니다. </li></ol> 4. 코어 재질의 해산에 의한 빈 입자의 작성 <ol><li> 불화 수 소산​​ 산성을 추가하는 전체 과정에 대한 퓸 후드 아래에 샘플을 놓습니다. </li><li> 불화 수 소산​​ 산성은 매우 공동입니다눈 및 피부의 rrosive 산성 및 노출은 영구적인 손상을 줄 수 있습니다. 얼굴 방패로 고글을 사용하고 HF를 다룰 때 실험실 코트를 착용하십시오. </li><li> 10 ML 탈이온수와 불화 수 소산​​ 산성 (올드 리치 49 %)의 10 ML을 섞어서 코팅 입자가 들어있는 플라스틱 접시에 추가할 수 있습니다. </li><li> 자기 활동가에 플라스틱 접시를 놓고 핵심은 24 시간 동안 용해 수 있습니다. </li><li> 언젠가는 50 ML 탈이온수으로 샘플을 희석하고 1 시간 동안 시료를 원심 분리기 후. 플라스틱 용기의 상단에있는 액체 층을 버리고 플라스틱 배양 접시에있는 입자를 포함 아래쪽 레이어를 전송합니다. </li><li> 50 ML 탈이온수과 와동 샘플을 추가하고 다시 원심 분리기. 상위 레이어 배출하고 깨끗한 배양 접시에있는 입자 레이어를 전송합니다. </li><li> 에탄올로 입자를 워시 공기 샘플을 건조하고, 뚜껑과 함께 유리병에 속이 빈 입자를 전송하고 건조기에 입자 보관하십시오. </li></ol> 5. Chara투과율의 cterization (핵심 릴리스의 비율) 재료 : 핵심 자료에 대한 염화칼륨 <ol><li> 1리터 탈이온수과 KCl 혼합 0.0745 g에서 0.001 어금니 칼륨 염화물 (KCl) 용액을 준비합니다. </li><li> 일정한 출력 분무기 모델 3076의 유리병을 기입하고 병 뚜껑을 설치합니다. </li><li> 분무기의 가스 유입구에 연결되어 멤브레인 드라이어,로 압축 공기 호스를 연결합니다. 그런 다음 KCl nanoparticles를 수집하기 위해 아웃렛 호스에 필터를 부착합니다. </li><li> 점차적으로 압축 공기 밸브를 열고 멤브레인 드라이어를 통해 공기 흐름을 보자. 입자는 5 시간 동안 필터에 축적 허용합니다. </li><li> 압축 공기 밸브를 닫고 조심스럽게 필터를 제거하고 입자를 수집합니다. 코팅 공정 이전 건조기에서 입자를 놓습니다. </li><li> 균일하게 코팅 KCl 입자를 얻기 위해 프로토콜 2, 3을 따르십시오. </li><li> 10 ML deionized WA로 코팅 KCl를 섞어유리관에 ter. 완벽하게 샘플을 섞어하려면 솔루션으로 자기 활동가 중단하고 자기 활동가에 둡니다. 25 ° C.에 샘플을 품어 </li><li> 유리병에 전도도 미터 프로브 (써모 오리온 모델 105) 넣고 30 일 동안 전도성을 기록합니다. </li></ol> 6. 대표 결과 우리는 그림 2에 표시된, 산화물 (실리카), 염 (KCl)과 금속 (알루미늄)를 포함하여 핵심 재료의 다양한으로이 과정을 적용했습니다. 전송 전자 현미경은 영화의 요골 균일를 확인하고 두께를 측정하는 데 사용되었습니다. 우리는 37 나노미터의 직경은 200 nm의 (그림 2)에 이르기까지 성공적으로 코팅 입자를 가지고 있지만이 방법으로 치료할 수 입자의 크기에 아무런 근본적인 제한이 없습니다. 쉘 증착의 비율은 약 1 nm의 / 분입니다. 이것은 다소 느린 속도는 가능한 매우 필름의 두께를 제어할 수있게정확하게 증착 시간을 통해. 플라즈마-polymerized 껍질은 핵 물질이 에칭 또는 해산에 의해 제거 수있다는 사실에 의해 증명 투과 장벽이다. 그림 3은 실리카 코어가 제거된 후 남아있는 빈 껍질을 보여줍니다. 코어의 제거가 완료하며 영화의 요골 균일하며 두께가 꽤 높다. 이 영화를 통해 투자율을 평가의 목적을 위해 우리는 KCl의 해산이 솔루션의 이온 전도도를 통해 쉽게 모니터링할 수 있기 때문에 핵심 소재로서 KCl로 전환되었습니다. 그림 4는 네 개의 샘플에 대한 핵심에서 KCl의 출시를 보여줍니다 서로 다른 두께 20 nm의, 40 nm의, 75 nm의, 및 95 nm의 각각으로. 코팅 KCl 입자가 물에 중단되었으며 용액의 전도도는 30 일 기간 동안 미행했다. 네 개의 샘플 이외에 uncoated KCl 입자로 구성되어 컨트롤도 모니터링되었습니다. Uncoated KCl 입자 disso약 1 분 짧은 시간 내에 대비를 위해 2001 년 9 월 11. 반대로 코팅된 KCl은 상당히 느린 릴리스 율을 보여줍니다. 코팅 입자의 릴리스 프로필은 필름의 두께에 따라 완료하는 데 며칠이 걸립니다 훨씬 느린 릴리스 다음, 첫 번째 시간 내에 이루어지는 초기 버스트이 특징입니다. <img alt="그림 1" src="/files/ftp_upload/4113/4113fig1.jpg" /> 그림 1. nanoparticles, 플라즈마 증착 및 중공 입자 형성 준비 도식 표현. <img alt="그림 2" src="/files/ftp_upload/4113/4113fig2.jpg" /> 그림 2. TEM의 코팅의 이미지 (), (B) D와 실리카 입자 = 200 nm의, D = 37 nm의와 (다) 실리카 입자, D와 (D) 알루미늄 ~ 100 nm의, 그리고 (마) KCl 입자와 D = 100 nm의 <img alt="그림 3" src="/files/ftp_upload/4113/4113fig3.jpg" /> 그림 3. T200 nm의 직경, 그리고 (c) KCl 코어와 (), (B) 실리카 코어를 식각 후 EM 중공 입자의 이미지를. <img alt="그림 4" src="/files/ftp_upload/4113/4113fig4.jpg" /> 그림 4. 릴리스 프로파일 쉘 두께의 영향. 삽입된 페이지 그래프는 첫 번째 시간 동안 릴리스를 보여줍니다.

<ol>
	<li>Xu, X., Asher, S. A. <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+Utilization+of+Monodisperse+Hollow+Polymeric+Particles+in+Photonic+Crystals.">Synthesis and Utilization of Monodisperse Hollow Polymeric Particles in Photonic Crystals.</a> Journal of the American Chemical Society. 126, 7940-7945 (2004).</li><li>Lou, X., Archer, L., Yang, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hollow+Micro-/nanostructures:+Synthesis+and+Applications.">Hollow Micro-/nanostructures: Synthesis and Applications.</a> Advanced Material. 20, (2008).</li><li>Kim, D. J., Kang, J. Y., Kim, 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=Coating+of+TiO2+Thin+Films+on+Particles+by+a+Plasma+Chemical+Vapor+Deposition+Process.">Coating of TiO2 Thin Films on Particles by a Plasma Chemical Vapor Deposition Process.</a> Advanced Powder Technology. 21, 136-140 (2010).</li><li>Marino, E., Huijser, T., Creyghton, Y., van der Heijden, A. <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+Coating+of+Copper+Oxide+Nanoparticles+Using+Atmospheric+Pressure+Plasmas.">Synthesis and Coating of Copper Oxide Nanoparticles Using Atmospheric Pressure Plasmas.</a> Surface and Coatings Technology. 201, 9205-9208 (2007).</li><li>Hakim, L., King, D., Zhou, Y., Gump, C., George, S., Weimer, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoparticle+Coating+for+Advanced+Optical,+Mechanical+and+Rheological+Properties.">Nanoparticle Coating for Advanced Optical, Mechanical and Rheological Properties.</a> Advanced Functional Materials. 17, 3175-3181 (2007).</li><li>Kim, S. H., Kim, J., Kang, B., Uhm, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Superhydrophobic+CFx+Coating+via+In-Line+Atmospheric+RF+Plasma+of+He-CF4-H2.">Superhydrophobic CFx Coating via In-Line Atmospheric RF Plasma of He-CF4-H2.</a> Langmuir. 21, 12213-12217 (2005).</li></ol>

관심의 어떠한 충돌 선언 없습니다.

코팅 nanoparticles에서 가장 큰 도전 중 하나는 코팅과 기판 1,2 사이에 호환되는 화학을 제공하는 것입니다. 여기서 설명한 방법은 재료 고유 아니라는 장점이 있습니다. 플라즈마 폴리머는 특수 표면 변형 3에 대한 필요없이 하드 금속 (그림 2 (C)), 실리카 (그림 2 (C)), 실리콘, 또는 부드러운 재료 (예 : 폴리머)를 포함하여 기판의 다양한에서 우수한 접착력을...

<table border="1"><tbody><tr><td> 실리카 입자 </td><td> Geltech 주식 회사 </td><td></td><td></td></tr><tr><td> 염화칼륨 (크리스탈) </td><td> EMD 화학 주식 회사 </td><td></td><td></td></tr><tr><td> 이소 프로필 알코올 (99.9 %) </td><td> 시그마 - 올드 리치 </td><td></td><td></td></tr><tr><td> 불화 수 소산​​ 산성 (48~51%) </td><td> VWR </td><td></td><td></td></tr><tr><td> 파이프 및 플랜지 </td><td> Swagelok </td><td></td><td> ¼의 직경이 1 인치 </td></tr><tr><td> 펌프 적응 </td><td> 에드워즈 </td><td></td><td></td></tr><tr><td> 액체 질소 트랩 </td><td> &amp; N 주식 회사 </td><td></td><td></td></tr></tbody></table>

encapsulation and permeability characteristics of plasma polymerized hollow particles

이 프로토콜에서는 코어 쉘 nanostructures는 플라즈마 강화 화학 기상 증착에 의해 합성된다. 우리는 실리카와 칼륨 염화 등 다양한 고체 기판, 대한 이소프로판올의 플라즈마 중합에 의한 비정질 장벽을 생산하고 있습니다. 이 다재 다능한 기술은 누구의 두께가 1 nm의에서 100 nm의의 이상으로 어디 에나있을 수있는 영화를 입금하여, 37 nm의에서 1 마이크론까지 크기의 nanoparticles과 nanopowders을 치료하는 데 사용됩니다. 코어의 해산은 우리가 영화를 통해 침투의 속도를 공부할 수 있습니다. 이 실험에서 우리는 코팅 KCL의 nanocrystals에 의해 배리어 필름을 통해 KCl의 확산 계수를 결정하고 이후 물 속에 정지 코팅된 입자의 이온 전도도를 모니터링. 이 과정에서 가장 큰 관심은 캡슐과 solutes의 지연 릴리스입니다. 껍질의 두께는 우리가 릴리스의 속도를 제어하는​​ 독립 변수 중 하나입니다. 그것은 속도에 강력한 영향을 미치지릴리스의 어느 30 일 이상 장기 릴리스 (쉘 두께가 95 nm의이다)까지 여섯 시간 릴리스 (쉘 두께 20 nm의입니다)에서 증가한다. 릴리스 프로파일 특성 동작을 보여줍니다 해산의 시작 후 첫 5 분 및 핵심 자료의 모든 때까지 느린 릴리즈 중에 빠른 릴리스 (최종 재료의 35 %)이 나오는 거죠.

Watch this Scientific Journal Video about Encapsulation and Permeability Characteristics of Plasma Polymerized Hollow Particles at JoVE.com

Encapsulation and Permeability Characteristics of Plasma Polymerized Hollow Particles

우리는 몇 nm의 다양한 재료의 나노 크기의 입자에 대한 몇 백 nm의에 이르기까지 박막을 입금 플라즈마 강화된 화학 기상 증착을 사용했습니다. 우리 투자율 껍질의 두께에 의해 제어됩니다 중공 nanoshells을 생산하기 위해 이후 에칭 핵심 소재. 우리는 작은 solutes 이러한 코팅의 투자율을 특성화하고 이러한 장벽 며칠 동안 핵심 소재의 지속적인 출시를 제공할 수 있다고 보여줍니다.

플라즈마 Polymerized 빈 입자의 캡슐화 및 투과율 특성

In this protocol, core-shell nanostructures are synthesized by plasma enhanced chemical vapor deposition. We produce an amorphous barrier by plasma ...

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Permeability of Concrete

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10.6K 조회수.  The Pennsylvania State University. 우리는 몇 nm의 다양한 재료의 나노 크기의 입자에 대한 몇 백 nm의에 이르기까지 박막을 입금 플라즈마 강화된 화학 기상 증착을 사용했습니다. 우리 투자율 껍질의 두께에 의해 제어됩니다 중공 nanoshells을 생산하기 위해 이후 에칭 핵심 소재. 우리는 작은 solutes 이러한 코팅의 투자율을 특성화하고 이러한 장벽 며칠 동안 핵심 소재의 지속적인 출시를 제공할 ...

비디오: Encapsulation and Permeability Characteristics of Plasma Polymerized Hollow Particles

Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses

Early plasma is generated owing to high intensity laser irradiation of target and the subsequent target material ionization. Its dynamics plays a significant role in laser-material interaction, especially in the air environment1-11.
Early plasma evolution has been captured through pump-probe shadowgraphy1-3 and interferometry1,4-7. However, the studied time frames and applied laser parameter ranges are limited. For example, direct examinations of plasma front locations and electron number densities within a delay time of 100 picosecond (ps) with respect to the laser pulse peak are still very few, especially for the ultrashort pulse of a duration around 100 femtosecond (fs) and a low power density around 1014 W/cm2. Early plasma generated under these conditions has only been captured recently with high temporal and spatial resolutions12. The detailed setup strategy and procedures of this high precision measurement will be illustrated in this paper. The rationale of the measurement is optical pump-probe shadowgraphy: one ultrashort laser pulse is split to a pump pulse and a probe pulse, while the delay time between them can be adjusted by changing their beam path lengths. The pump pulse ablates the target and generates the early plasma, and the probe pulse propagates through the plasma region and detects the non-uniformity of electron number density. In addition, animations are generated using the calculated results from the simulation model of Ref. 12 to illustrate the plasma formation and evolution with a very high resolution (0.04 ~ 1 ps).
Both the experimental method and the simulation method can be applied to a broad range of time frames and laser parameters. These methods can be used to examine the early plasma generated not only from metals, but also from semiconductors and insulators.

An experimental method to examine the early plasma evolution induced by ultrashort laser pulses is described. Using this method, high quality images of early plasma are obtained with high temporal and spatial resolutions. A novel integrated atomistic model is used to simulate and explain the mechanisms of early plasma.

초기 플라즈마 진화의 조사는 극단으로 짧은 레이저 펄스에 의해 유도된

Early plasma is generated owing to high intensity laser irradiation of target and the subsequent target material ionization. Its dynamics plays a ...

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공학

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids

An experimental study is performed to measure the terminal settling velocities of spherical particles in surfactant based shear thinning viscoelastic (VES) fluids. The measurements are made for particles settling in unbounded fluids&#160;and fluids between parallel walls. VES fluids over a wide range of rheological properties are prepared and rheologically characterized. The rheological characterization involves steady shear-viscosity and dynamic oscillatory-shear measurements to quantify the viscous and elastic properties respectively. The settling velocities under unbounded conditions are measured in beakers having diameters at least 25x the diameter of particles. For measuring settling velocities between parallel walls, two experimental cells with different wall spacing are constructed. Spherical particles of varying sizes are gently dropped in the fluids and allowed to settle. The process is recorded with a high resolution video camera and the trajectory of the particle is recorded using image analysis software. Terminal settling velocities are calculated from the data.
The impact of elasticity on settling velocity in unbounded fluids is quantified by comparing the experimental settling velocity to the settling velocity calculated by the inelastic drag predictions of Renaud et al.1&#160;Results show that elasticity of fluids can increase or decrease the settling velocity. The magnitude of reduction/increase is a function of the rheological properties of the fluids and properties of particles. Confining walls are observed to cause a retardation effect on settling and the retardation is measured in terms of wall factors.

This paper demonstrates the experimental procedure to measure terminal settling velocities of spherical particles in surfactant-based shear thinning viscoelastic fluids. Fluids over a wide range of rheological properties are prepared and settling velocities are measured for a range of particle sizes in unbounded fluids and fluids between parallel walls.

An experimental study is performed to measure the terminal settling velocities of spherical particles in surfactant based shear thinning viscoelastic ...

How to Ignite an Atmospheric Pressure Microwave Plasma Torch without Any Additional Igniters

This movie shows how an atmospheric pressure plasma torch can be ignited by microwave power with no additional igniters. After ignition of the plasma, a stable and continuous operation of the plasma is possible and the plasma torch can be used for many different applications. On one hand, the hot (3,600 K gas temperature) plasma can be used for chemical processes and on the other hand the cold afterglow (temperatures down to almost RT) can be applied for surface processes. For example chemical syntheses are interesting volume processes. Here the microwave plasma torch can be used for the decomposition of waste gases which are harmful and contribute to the global warming but are needed as etching gases in growing industry sectors like the semiconductor branch. Another application is the dissociation of CO2. Surplus electrical energy from renewable energy sources can be used to dissociate CO2 to CO and O2. The CO can be further processed to gaseous or liquid higher hydrocarbons thereby providing chemical storage of the energy, synthetic fuels or platform chemicals for the chemical industry. Applications of the afterglow of the plasma torch are the treatment of surfaces to increase the adhesion of lacquer, glue or paint, and the sterilization or decontamination of different kind of surfaces. The movie will explain how to ignite the plasma solely by microwave power without any additional igniters, e.g., electric sparks. The microwave plasma torch is based on a combination of two resonators &#8212; a coaxial one which provides the ignition of the plasma and a cylindrical one which guarantees a continuous and stable operation of the plasma after ignition. The plasma can be operated in a long microwave transparent tube for volume processes or shaped by orifices for surface treatment purposes.

This movie shows how an atmospheric plasma torch can be ignited by microwaves with no additional igniters and provides a stable and continuous plasma operation suitable for plenty of applications.

어떻게 추가 점화기없이 대기압 마이크로 웨이브 플라즈마 토치를 점화

This movie shows how an atmospheric pressure plasma torch can be ignited by microwave power with no additional igniters. After ignition of the plasma, a ...

Methods for Measuring the Orientation and Rotation Rate of 3D-printed Particles in Turbulence

Experimental methods are presented for measuring the rotational and translational motion of anisotropic particles in turbulent fluid flows. 3D printing technology is used to fabricate particles with slender arms connected at a common center. Shapes explored are crosses (two perpendicular rods), jacks (three perpendicular rods), triads (three rods in triangular planar symmetry), and tetrads (four arms in tetrahedral symmetry). Methods for producing on the order of 10,000 fluorescently dyed particles are described. Time-resolved measurements of their orientation and solid-body rotation rate are obtained from four synchronized videos of their motion in a turbulent flow between oscillating grids with R&#955; = 91. In this relatively low-Reynolds number flow, the advected particles are small enough that they approximate ellipsoidal tracer particles. We present results of time-resolved 3D trajectories of position and orientation of the particles as well as measurements of their rotation rates.

We use 3D printing to fabricate anisotropic particles in the shapes of jacks, crosses, tetrads, and triads, whose alignments and rotations in turbulent fluid flow can be measured from multiple simultaneous video images.

Experimental methods are presented for measuring the rotational and translational motion of anisotropic particles in turbulent fluid flows. 3D printing ...

Fabrication and Operation of Acoustofluidic Devices Supporting Bulk Acoustic Standing Waves for Sheathless Focusing of Particles

Acoustophoresis refers to the displacement of suspended objects in response to directional forces from sound energy. Given that the suspended objects must be smaller than the incident wavelength of sound and the width of the fluidic channels are typically tens to hundreds of micrometers across, acoustofluidic devices typically use ultrasonic waves generated from a piezoelectric transducer pulsating at high frequencies (in the megahertz range). At characteristic frequencies that depend on the geometry of the device, it is possible to induce the formation of standing waves that can focus particles along desired fluidic streamlines within a bulk flow. Here, we describe a method for the fabrication of acoustophoretic devices from common materials and clean room equipment. We show representative results for the focusing of particles with positive or negative acoustic contrast factors, which move towards the pressure nodes or antinodes of the standing waves, respectively. These devices offer enormous practical utility for precisely positioning large numbers of microscopic entities (e.g., cells) in stationary or flowing fluids for applications ranging from cytometry to assembly.

Acoustofluidic devices use ultrasonic waves within microfluidic channels to manipulate, concentrate and isolate suspended micro and nanoscopic entities. This protocol describes the fabrication and operation of such a device supporting bulk acoustic standing waves to focus particles in a central streamline without the aid of sheath fluids.

제조 및 Acoustofluidic 장치의 작동은 입자의 초점 쉬스에 대한 대량 음향 서 파도 지원

Acoustophoresis refers to the displacement of suspended objects in response to directional forces from sound energy. Given that the suspended objects must ...

Applying X-ray Imaging Crystal Spectroscopy for Use as a High Temperature Plasma Diagnostic

X-ray spectra provide a wealth of information on high temperature plasmas; for example electron temperature and density can be inferred from line intensity ratios. By using a Johann spectrometer viewing the plasma, it is possible to construct profiles of plasma parameters such as density, temperature, and velocity with good spatial and time resolution. However, benchmarking atomic code modeling of X-ray spectra obtained from well-diagnosed laboratory plasmas is important to justify use of such spectra to determine plasma parameters when other independent diagnostics are not available. This manuscript presents the operation of the High Resolution X-ray Crystal Imaging Spectrometer with Spatial Resolution (HIREXSR), a high wavelength resolution spatially imaging X-ray spectrometer used to view hydrogen- and helium-like ions of medium atomic number elements in a tokamak plasma. In addition, this manuscript covers a laser blow-off system that can introduce such ions to the plasma with precise timing to allow for perturbative studies of transport in the plasma.

X-ray spectra provide a wealth of information on high temperature plasmas. This manuscript presents the operation of a high wavelength resolution spatially imaging X-ray spectrometer used to view hydrogen- and helium-like ions of medium atomic number elements in a tokamak plasma.

하이 온도 플라즈마 진단으로 사용하기 위해 X 선 영상 크리스탈 분광학 적용

X-ray spectra provide a wealth of information on high temperature plasmas; for example electron temperature and density can be inferred from line ...

Effect of Bending on the Electrical Characteristics of Flexible Organic Single Crystal-based Field-effect Transistors

The charge transport in an organic semiconductor depends highly on the molecular packing in the crystal, which influences the electronic coupling immensely. However, in soft electronics, in which organic semiconductors play a critical role, the devices will be bent or folded repeatedly. The effect of bending on the crystal packing and thus the charge transport is crucial to the performance of the device. In this manuscript, we describe the protocol to bend a single crystal of 5,7,12,16-tetrachloro-6,13-diazapentacene (TCDAP) in the field-effect transistor configuration and to obtain reproducible I-V characteristics upon bending the crystal. The results show that bending a field-effect transistor prepared on a flexible substrate results in nearly reversible yet opposite trends in charge mobility, depending on the bending direction. The mobility increases when the device is bent toward the top gate/dielectric layer (upward, compressive state) and decreases when bent toward the crystal/substrate side (downward, tensile state). The effect of bending curvature was also observed, with greater mobility change resulting from higher bending curvature. It is suggested that the intermolecular &#960;-&#960; distance changes upon bending, thereby influencing the electronic coupling and the subsequent carrier transport ability.

This manuscript describes the bending process of an organic single crystal-based field-effect transistor to maintain a functioning device for electronic property measurement. The results suggest that bending causes changes in the molecular spacing in the crystal and thus in the charge hopping rate, which is important in flexible electronics.

유연한 유기 단결정 기반 전계 효과 트랜지스터의 전기적 특성에 영향 절곡

The charge transport in an organic semiconductor depends highly on the molecular packing in the crystal, which influences the electronic coupling ...

An Atmospheric Pressure Plasma Setup to Investigate the Reactive Species Formation

Non-thermal atmospheric pressure (&#39;cold&#39;) plasmas have received increased attention in recent years due to their significant biomedical potential. The reactions of cold plasma with the surrounding atmosphere yield a variety of reactive species, which can define its effectiveness. While efficient development of cold plasma therapy requires kinetic models, model benchmarking needs empirical data. Experimental studies of the source of reactive species detected in aqueous solutions exposed to plasma are still scarce. Biomedical plasma is often operated with He or Ar feed gas, and a specific interest lies in investigation of the reactive species generated by plasma with various gas admixtures (O2, N2, air, H2O vapor, etc.) Such investigations are very complex due to difficulties in controlling the ambient atmosphere in contact with the plasma effluent. In this work, we addressed common issues of &#39;high&#39; voltage kHz frequency driven plasma jet experimental studies. A reactor was developed allowing the exclusion of ambient atmosphere from the plasma-liquid system. The system thus comprised the feed gas with admixtures and the components of the liquid sample. This controlled atmosphere allowed the investigation of the source of the reactive oxygen species induced in aqueous solutions by He-water vapor plasma. The use of isotopically labelled water allowed distinguishing between the species originating in the gas phase and those formed in the liquid. The plasma equipment was contained inside a Faraday cage to eliminate possible influence of any external field. The setup is versatile and can aid in further understanding the cold plasma-liquid interactions chemistry.

An experimental setup was created for the helium-operated kHz frequency plasma jet. The setup includes a cage for the plasma power supply and jet and an in-house built reactor to monitor plasma-induced reactive species without the interference of the ambient atmosphere.

대기압 플라즈마 설치 프로그램은 반응성 종 형성을 조사하기

Non-thermal atmospheric pressure (&#39;cold&#39;) plasmas have received increased attention in recent years due to their significant biomedical potential. ...

Spark Plasma Sintering Apparatus Used for the Formation of Strontium Titanate Bicrystals

A spark plasma sintering apparatus was used as a novel method for diffusion bonding of two single crystals of strontium titanate to form bicrystals with one twist grain boundary. This apparatus utilizes high uniaxial pressure and a pulsed direct current for rapid consolidation of material. Diffusion bonding of strontium titanate bicrystals without fracture, in a spark plasma sintering apparatus, is possible at high pressures due to the unusual temperature dependent plasticity behavior of strontium titanate. We demonstrate a method for the successful formation of bicrystals at accelerated time scales and lower temperatures in a spark plasma sintering apparatus compared to bicrystals formed by conventional diffusion bonding parameters. Bond quality was verified by scanning electron microscopy. A clean and atomically abrupt interface containing no secondary phases was observed using transmission electron microscopy techniques. Local changes in bonding across the boundary was characterized by simultaneous scanning transmission electron microscopy and spatially resolved electron energy-loss spectroscopy.

A viable technique for the formation of strontium titanate bicrystals at high pressure and fast heating rate via the spark plasma sintering apparatus is developed.

스트론튬 티탄 Bicrystals의 형성에 사용되는 플라즈마 소결 장치 불꽃

A spark plasma sintering apparatus was used as a novel method for diffusion bonding of two single crystals of strontium titanate to form bicrystals with ...

Optimization, Test and Diagnostics of Miniaturized Hall Thrusters

Miniaturized spacecraft and satellites require smart, highly efficient and durable low-thrust thrusters, capable of extended, reliable operation without attendance and adjustment. Thermochemical thrusters which utilize thermodynamic properties of gases as a means of acceleration have physical limitations on their exhaust gas velocity, resulting in low efficiency. Moreover, these engines demonstrate extremely low efficiency at small thrusts and may be unsuitable for continuously operating systems which provide real-time adaptive control of the spacecraft orientation, velocity and position. In contrast, electric propulsion systems which use electromagnetic fields to accelerate ionized gases (i.e., plasmas) do not have any physical limitation in terms of exhaust velocity, allowing virtually any mass efficiency and specific impulse. Low-thrust Hall thrusters have a lifetime of several thousand hours. Their discharge voltage ranges between 100 and 300 V, operating at a nominal power of &lt;1 kW. They vary from 20 to 100 mm in size. Large Hall thrusters can provide fractions of millinewton of thrust. Over the past few decades, there has been an increasing interest in small mass, low power, and high efficiency propulsion systems to drive satellites of 50-200 kg. In this work, we will demonstrate how to build, test, and optimize a small (30 mm) Hall thruster capable of propelling a small satellite weighing about 50 kg. We will show the thruster operating in a large space environment simulator, and describe how thrust is measured and electric parameters, including plasma characteristics, are collected and processed to assess key thruster parameters. We will also demonstrate how the thruster is optimized to make it one of the most efficient small thrusters ever built. We will also address challenges and opportunities presented by new thruster materials.

Here, we present a protocol to test and optimize space propulsion systems based on miniaturized Hall-type thrusters.

최적화, 테스트 그리고 소형된 홀 로켓의 진단

Miniaturized spacecraft and satellites require smart, highly efficient and durable low-thrust thrusters, capable of extended, reliable operation without ...