This research was supported by the "Development of technologies for safety evaluation and standardization of nanomaterials and nanoproducts" (10059135)" through the Korea Evaluation Institute of Industrial Technology by the Korean Ministry of Trade, Industry &amp; Energy.

1.仪器和样品的制备<ol><li> Abrasor <ol><li>基于磨耗试验机，使用一个abrasor与一种样品旋转台（140毫米直径），两个磨轮支架，和30的旋转速度 - 80转。 </li><li>使用权重的磨损轮固定在磨损轮夹持，这也适用于负载的试样。 </li><li>安装一个额外的空气入口为abrased颗粒提供较好的悬浮， 如图3。使用1/8" -直径管仅有15毫米的位置和40 mm的试验片的中心距离。 </li></ol></li><li> 砂轮 <ol><li>包裹砂轮（直径55毫米13毫米厚）用砂纸（100砂砾和全新的）。 </li></ol></li><li> 标本 <ol><li>样品是包含磨耗试验纳米材料的复合材料。要安装在abrasor，试样应该准备机智ħ140毫米直径。 </li></ol></li><li> 房间 <ol><li>使用不锈钢室壁以避免由于静电力颗粒沉积。放置所述腔室（体积1米3）（ 表1）内的abrasor，并分别定位在腔室的上部和下部的空气入口和出口。使用混合器，由三个多孔板，在空气出口处实现了均匀混合的颗粒流。 </li></ol></li><li> 中和剂 <ol><li>作为静电的颗粒提高在室壁上颗粒沉积，使用的中和剂（软X射线离子发生器），以最大限度地减少颗粒的带电状态。 </li></ol></li><li> 在线测量仪器12，13 <ol><li>使用单次点击和OPC来测量粒子个数浓度和粒度分布按照制造商的说明。 </li><li>安装在outle党和OPC腔室的吨至测量颗粒个数浓度及粒径分布。 </li></ol></li><li> 粒子采样仪器 <ol><li>样品使用含粒子取样的过滤介质或TEM网格来分析颗粒形态和成分的释放的粒子。 </li><li>在腔室的出口处安装含粒子取样的过滤介质或TEM网格来分析释放颗粒的形态。 </li></ol></li></ol>使用室系统2.磨损试验的纳米粒子释放注:磨损试验条件在表2中描述。 <ol><li>定位在腔室的中心abrasor。 </li><li>在abrasor的试样旋转阶段安装试验片。 </li><li>固定在磨轮支架的磨损轮与千克体重施加负载到测试样品。 </li><li>找到中和剂（软X射线离子发生器）28厘米从试样在45°角的中心距离，如在图2中看到的，为了减少在室壁上的静电颗粒沉积。 注:中和剂删除由束曝光的静电力。然而，由于进气口和磨损轮上方的样品旋转台，这限制了中和剂束到测试样品表面的访问。因此，在中和器位于斜，以允许光束到达尽可能多的试样表面尽可能的。 </li><li>操作安装在腔室的出口的鼓风机以50升/分钟的流速。 </li><li>供给25升/分钟，用空气压缩机通过附加空气入口附加无颗粒的悬浮液的空气。 注:颗粒，这是由摩擦而产生的，沉积在试样和磨损轮的表面上，强烈。因此，很难以测量abrased颗粒。额外的进气口可以HELp来解决这个问题，以粒子悬浮液。 </li><li>检查背景颗粒数浓度腔室内部达到的平均颗粒数浓度使用中共低于1＃/立方厘米1小时，如在图4中描述。 </li><li>操作使用的步进马达，在每分钟72与1000转旋转试样旋转阶段abrasor的检体旋转的阶段。 </li><li>测量并记录使用党和OPC释放的粒子数浓度和粒径分布。 注意:从纳米复合材料释放的颗粒悬浮和通过正被泵送的空气中进行。这些悬浮颗粒最终被输送到气流以下的出口。被释放的颗粒然后由中共和OPC在腔室的出口处检测到。每次点击成本和OPC最常用于测量粒子个数浓度，而一个OPC还可以测量粒径分布。 </li><li>桑普乐使用含有过滤介质或TEM网格上的粒子采样器释放粒子。 注:因磨损举动从纳米复合材料释放到腔室的气流以下出口处的颗粒。在腔室的出口，被释放的颗粒可以使用粒子采样进行采样。收集在过滤介质或TEM网格释放粒子然后可以用TEM或SEM（扫描电子显微镜）分析。 </li><li>停止测量和取样时，下面的粒子个数浓度达到峰值粒子个数浓度为0.1％。 </li><li>保存所有数据（CPC，OPC），并删除所有样品（样品）。 </li><li>使用一个新的样品和新磨损轮为每个测试，和洗涤腔室和各磨损试验后的Kimwipes和IPA（异丙醇）abrasor确认重复性。 </li></ol>

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The authors have nothing to disclose.

使用的磨损试验进行从纳米复合材料nanorelease测试时最重要的步骤是:1使用具有中和剂由不锈钢制成的腔室系统以除去因磨损所产生的静电荷，并减少在室壁上的颗粒的沉积）; 2）提供额外的空气以提供更好的颗粒悬浮液; 3）抽样利用包含由三个多孔板的混频器出口的中国共产党和OPC释放粒子和在线监测。 耐磨测试仪最初设计基于ISO 7784-1或ISO 5470-1 14-15评估耐磨性。耐...

纳米材料的曝光大多被研究有关工人工作场所制造，处理，制造，包装纳米材料，而消费者接触还没有被广泛研究。通过纳米技术国际理事会（ICON）创造了环境和健康文献数据库的最近的分析也表明，大多数纳米材料安全性研究都集中在危害（83％）和潜在风险（16％），与纳米复合材料的发布，代表消费者接触，仅相当于0.8％1。因此，很少有人知道有关消费者接触纳米材料。 纳米颗粒释放已被用来估计在模拟研究，包括磨损，纳米复合材料，洗涤纺织品，或含尘测试方法，如旋转鼓的方法，涡流振荡方法以及其它摇床方法2-3的风化消费者接触。此外，一些国际尝试，如ILSI（国际生命科学研究所）nanorelease和欧盟NanoReg，已经进行了技术开发，以了解在消费产品中使用的纳米材料的释放。于2011年推出的ILSI nanorelease消费产品代表了生命周期方法，从消费类产品，其中第一阶段涉及纳米材料的选择纳米材料的释放，第二阶段涵盖的评价方法，以及第3阶段实施间研究。在消费类产品纳米材料的安全性几个专着和出版物也已出版了4-6。 同时，NanoReg代表欧洲共同的方法来制造纳米材料的法规测试，并提供了在使用模拟方法的程序方法，从消费产品到nanorelease 2. ISO TC 229还试图制定有关消费者的安全标准，并提交新工作项目建议为消费者的安全。经合组织WPMN（worki纳克纳米材料派对），特别是SG8（督导组暴露评估和暴露减缓），最近在今后的工作，尤其是消费者和环境暴露评估的方向进行了调查。因此，在这些国际活动的光，贸易，工业和能源部韩国部委发起于2013年的分层项目主要集中在了"纳米材料和纳米产品的安全性评价和标准化的技术发展。"此外，一些消费者安全相关的研究，以规范从消费产品的纳米材料的释放也已出版了7-8。 磨损试验是包括在ILSI nanorelease和NanoReg 2-3用于确定从不同的商业复合产品纳米颗粒的电势发射电平的模拟方法之一。质量重量损失推导基于之前和阿巴拉后在试样重量差离子使用abrasor。所述纳米复合材料样品以恒定的速度磨损，采样吸收了气溶胶，然后将颗粒用粒子计数装置，如一个冷凝粒子计数器（CPC）或光学粒子计数器（OPC）进行分析，并收集在TEM （透射电子显微镜）网格或膜，用于进一步的视觉分析。然而，进行了纳米复合物材料的磨损试验需要一致的纳米颗粒的释放，这是困难的，因为颗粒充电作为磨损的结果，并当粒子采样发光点2-3，9-11邻近进行。 因此，本文提出了一种腔系统，作为纳米复合材料的磨损情况评估纳米材料释放的新方法。当与其它磨损和模拟测试相比，该室系统提供了在磨损的情况下一致纳米粒子释放的数据。此外，这种新的测试方法已在室内空气质量和半行为行业占总粒子数的计数方法的领域广泛使用的12，13，因此，可以预见，该方法可被开发成用于从含有消费品测试纳米粒子释放的标准化方法纳米材料。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Foamex</td>
			<td>Taeyoung, R. of Korea</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>MWCNT (multiwalled carbon nanotube) composite</td>
			<td>Hanwha, Incheon, R. of Korea</td>
			<td></td>
			<td>2% MWCNTs in low density polyethylene</td>
		</tr>
		<tr>
			<td>Abrasion Paper</td>
			<td>Derfos, R. of Korea</td>
			<td>#100</td>
			<td>100 grit sand paper</td>
		</tr>
		<tr>
			<td>Condensation Particle Counter (CPC)</td>
			<td>TSI Inc, Shoreview, MN</td>
			<td>UCPC 3775</td>
			<td></td>
		</tr>
		<tr>
			<td>Optical Paritcle Counter (OPC)</td>
			<td>Grimm, Ainring, Germany</td>
			<td>1.109</td>
			<td></td>
		</tr>
		<tr>
			<td>Mini Particle Sampler</td>
			<td>Ecomesure, Saclay, France</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Quantifoil Holey Carbon Film</td>
			<td>TED PELLA Inc. USA</td>
			<td>1.2/1.3</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter Holder</td>
			<td></td>
			<td></td>
			<td>custom made</td>
		</tr>
		<tr>
			<td>Polycarbonate Filter&#160;</td>
			<td>Millipore, USA</td>
			<td>CAT No. GTTP02500</td>
			<td></td>
		</tr>
		<tr>
			<td>Soft X-ray Ionizer (Neutralizer)</td>
			<td>SUNJE, R. of Korea</td>
			<td>SXN-05U</td>
			<td></td>
		</tr>
		<tr>
			<td>Field Emission-Scanning Electron Microscope (FE-SEM)</td>
			<td>Hitachi</td>
			<td>S-4300</td>
			<td></td>
		</tr>
	</tbody>
</table>

testing of nanoparticle release from a composite containing nanomaterial using a chamber system

随着纳米技术作为在 21世纪最重要的技术之一的迅速发展，在含有纳米材料的消费品的安全利益也越来越多。从评估含有纳米材料的产品的纳米材料释放在评估这些产品的安全性的关键一步，并导致一些国际努力，以建立一致的，可靠的技术，为规范纳米材料释放的评价。在这项研究中，从含有纳米材料的制品纳米材料的释放，使用的腔室系统，其包括缩合粒子计数器，光学粒子计数器，和取样口，以收集电子显微镜分析滤波器样品进行评价。所提出的腔室系统是使用abrasor和圆盘型纳米复合材料样品以确定所述纳米材料释放是否是在可接受的范围内可重复和一致的测试。测试结果表明，颗粒在每个测试的总数是从平均20％的范围内经过多次试验。流行趋势的发布是相似的，它们显示出非常良好的重复性。因此，所提出的腔室系统可有效地用于含纳米材料的纳米材料的产品释放测试。

磨损试验重复性使用室系统总颗粒数分别为8磨损试验相一致，如表3所示。中共测定3.67×10 9个粒子的平均值，而在OPC计数1.98×10 9颗粒（&gt; 0.3微米）的平均。的偏差为20％，这表示磨损期间颗粒的一致释放内。 Nanorelease从纳米复合材料<p class="jove_content" f...

Watch this Scientific Journal Video about Testing of Nanoparticle Release from a Composite Containing Nanomaterial Using a Chamber System at JoVE.com

Testing of Nanoparticle Release from a Composite Containing Nanomaterial Using a Chamber System

Nanoparticle release is tested using a chamber system that includes a condensation particle counter, an optical particle counter and sampling ports to collect filter samples for microscopy analysis. The proposed chamber system can be effectively used for nanomaterial release testing with a repeatable and consistent data range.

从使用室系统一个复合含纳米材料的纳米颗粒释放测试

With the rapid development of nanotechnology as one of the most important technologies in the 21st century, interest in the safety of consumer products ...

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6.7K 次观看.  Hanyang University. Nanoparticle release is tested using a chamber system that includes a condensation particle counter, an optical particle counter and sampling ports to collect filter samples for microscopy analysis. The proposed chamber system can be effectively used for nanomaterial release testing with a repeatable and consistent data range.

视频: Testing of Nanoparticle Release from a Composite Containing Nanomaterial Using a Chamber System

Characterization of Recombination Effects in a Liquid Ionization Chamber Used for the Dosimetry of a Radiosurgical Accelerator

Most modern radiation therapy devices allow the use of very small fields, either through beamlets in Intensity-Modulated Radiation Therapy (IMRT) or via stereotactic radiotherapy where positioning accuracy allows delivering very high doses per fraction in a small volume of the patient. Dosimetric measurements on medical accelerators are conventionally realized using air-filled ionization chambers. However, in small beams these are subject to nonnegligible perturbation effects. This study focuses on liquid ionization chambers, which offer advantages in terms of spatial resolution and low fluence perturbation. Ion recombination effects are investigated for the microLion detector (PTW) used with the Cyberknife system (Accuray). The method consists of performing a series of water tank measurements at different source-surface distances, and applying corrections to the liquid detector readings based on simultaneous gaseous detector measurements. This approach facilitates isolating the recombination effects arising from the high density of the liquid sensitive medium and obtaining correction factors to apply to the detector readings. The main difficulty resides in achieving a sufficient level of accuracy in the setup to be able to detect small changes in the chamber response.

A growing number of radiation therapy devices offer the advantage of delivering the dose through very small beams to the tumor, allowing for increased conformity and higher doses per fraction. Many different detectors can be used for the dosimetry of these small fields. In the present study, the effect of ion recombination is investigated for a liquid ionization chamber using a stereotactic radiation therapy system.

重组的影响在液体电离室表征用于一个电波加速器的剂量学

Most modern radiation therapy devices allow the use of very small fields, either through beamlets in Intensity-Modulated Radiation Therapy (IMRT) or via ...

科研

工程学

Visible-light Induced Reduction of Graphene Oxide Using Plasmonic Nanoparticle

Present work demonstrates the simple, chemical free, fast, and energy efficient method to produce reduced graphene oxide (r-GO) solution at RT using visible light irradiation with plasmonic nanoparticles. The plasmonic nanoparticle is used to improve the reduction efficiency of GO. It only takes 30 min&#160;at RT by illuminating the solutions with Xe-lamp, the r-GO solutions can be obtained by completely removing gold nanoparticles through simple centrifugation step. The spherical gold nanoparticles (AuNPs) as compared to the other nanostructures is the most suitable plasmonic nanostructure for r-GO preparation. The reduced graphene oxide prepared using visible light and AuNPs was equally qualitative as chemically reduced graphene oxide, which was supported by various analytical techniques such as UV-Vis spectroscopy, Raman spectroscopy, powder XRD and XPS. The reduced graphene oxide prepared with visible light shows excellent quenching properties over the fluorescent molecules modified on ssDNA and excellent fluorescence recovery for target DNA detection. The r-GO prepared by recycled AuNPs is found to be of same quality with that of chemically reduced r-GO. The use of visible light with plasmonic nanoparticle demonstrates the good alternative method for r-GO synthesis.

A simple protocol for the preparation of reduced graphene oxide using visible light and plasmonic nanoparticle is described.

可见光诱导的还原氧化石墨烯的使用电浆纳米粒子

Present work demonstrates the simple, chemical free, fast, and energy efficient method to produce reduced graphene oxide (r-GO) solution at RT using ...

Measurement of Scattering Nonlinearities from a Single Plasmonic Nanoparticle

Plasmonics, which are based on the collective oscillation of electrons due to light excitation, involve strongly enhanced local electric fields and thus have potential applications in nonlinear optics, which requires extraordinary optical intensity. One of the most studied nonlinearities in plasmonics is nonlinear absorption, including saturation and reverse saturation behaviors. Although scattering and absorption in nanoparticles are closely correlated by the Mie theory, there has been no report of nonlinearities in plasmonic scattering until very recently. 
Last year, not only saturation, but also reverse saturation of scattering in an isolated plasmonic particle was demonstrated for the first time. The results showed that saturable scattering exhibits clear wavelength dependence, which seems to be directly linked to the localized surface plasmon resonance (LSPR). Combined with the intensity-dependent measurements, the results suggest the possibility of a common mechanism underlying the nonlinear behaviors of scattering and absorption. These nonlinearities of scattering from a single gold nanosphere (GNS) are widely applicable, including in super-resolution microscopy and optical switches. 
In this paper, it is described in detail how to measure nonlinearity of scattering in a single GNP and how to employ the super-resolution technique to enhance the optical imaging resolution based on saturable scattering. This discovery features the first super-resolution microscopy based on nonlinear scattering, which is a novel non-bleaching contrast method that can achieve a resolution as low as l/8 and will potentially be useful in biomedicine and material studies.

Saturable and reverse saturable scattering were discovered in isolated plasmonic particles and adopted as a novel non-bleaching contrast method in super-resolution microscopy. Here the experimental procedures of detecting and extracting nonlinear scattering are explained in detail, as well as how to enhance resolution with the aid of saturated excitation microscopy.

从单电浆纳米粒子散射非线性测量

Plasmonics, which are based on the collective oscillation of electrons due to light excitation, involve strongly enhanced local electric fields and thus ...

Ultrasonic Welding of Thermoplastic Composite Coupons for Mechanical Characterization of Welded Joints through Single Lap Shear Testing

This paper presents a novel straightforward method for ultrasonic welding of thermoplastic-composite coupons in optimum processing conditions. The ultrasonic welding process described in this paper is based on three main pillars. Firstly, flat energy directors are used for preferential heat generation at the joining interface during the welding process. A flat energy director is a neat thermoplastic resin film that is placed between the parts to be joined prior to the welding process and heats up preferentially owing to its lower compressive stiffness relative to the composite substrates. Consequently, flat energy directors provide a simple solution that does not require molding of resin protrusions on the surfaces of the composite substrates, as opposed to ultrasonic welding of unreinforced plastics. Secondly, the process data provided by the ultrasonic welder is used to rapidly define the optimum welding parameters for any thermoplastic composite material combination. Thirdly, displacement control is used in the welding process to ensure consistent quality of the welded joints. According to this method, thermoplastic-composite flat coupons are individually welded in a single lap configuration. Mechanical testing of the welded coupons allows determining the apparent lap shear strength of the joints, which is one of the properties most commonly used to quantify the strength of thermoplastic composite welded joints.

A straightforward procedure for ultrasonic welding of thermoplastic composite coupons for basic mechanical testing is described. Key characteristics of this ultrasonic welding process are the use of flat energy directors for simplified process preparation and the use of process data for the fast definition of optimum processing conditions.

通过单搭接剪切试验的热塑性复合材料优惠券焊接接头的力学特性的超声波焊接

This paper presents a novel straightforward method for ultrasonic welding of thermoplastic-composite coupons in optimum processing conditions. The ...

Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging

The fabrication of polymer-nanoparticle composites is extremely important in the development of many functional materials. Identifying the precise composition of these materials is essential, especially in the design of surface catalysts, where the surface concentration of the active component determines the activity of the material. Antimicrobial materials which utilize nanoparticles are a particular focus of this technology. Recently swell encapsulation has emerged as a technique for inserting antimicrobial nanoparticles into a host polymer matrix. Swell encapsulation provides the advantage of localizing the incorporation to the external surfaces of materials, which act as the active sites of these materials. However, quantification of this nanoparticle uptake is challenging. Previous studies explore the link between antimicrobial activity and surface concentration of the active component, but this is not directly visualized. Here we show a reliable method to monitor the incorporation of nanoparticles into a polymer host matrix via swell encapsulation. We show that the surface concentration of CdSe/ZnS nanoparticles can be accurately visualized through cross-sectional fluorescence imaging. Using this method, we can quantify the uptake of nanoparticles via swell encapsulation and measure the surface concentration of encapsulated particles, which is key in optimizing the activity of functional materials.

Here we present a reliable method to monitor the incorporation of nanoparticles into a polymer host matrix via swell encapsulation. We show that the surface concentration of cadmium selenide quantum dots can be accurately visualized through cross-sectional fluorescence imaging.

纳米粒子 - 聚合物复合材料使用直接荧光成像的先进成分分析

The fabrication of polymer-nanoparticle composites is extremely important in the development of many functional materials. Identifying the precise ...

A System to Create Stable Nanoparticle Aerosols from Nanopowders

Nanoparticle aerosols released from nanopowders in workplaces are associated with human exposure and health risks. We developed a novel system, requiring minimal amounts of test materials (min. 200 mg), for studying powder aerosolization behavior and aerosol properties. The aerosolization procedure follows the concept of the fluidized-bed process, but occurs in the modified volume of a V-shaped aerosol generator. The airborne particle number concentration is adjustable by controlling the air flow rate. The system supplied stable aerosol generation rates and particle size distributions over long periods (0.5-2 hr and possibly longer), which are important, for example, to study aerosol behavior, but also for toxicological studies. Strict adherence to the operating procedures during the aerosolization experiments ensures the generation of reproducible test results. The critical steps in the standard protocol are the preparation of the material and setup, and the aerosolization operations themselves. The system can be used for experiments requiring stable aerosol concentrations and may also be an alternative method for testing dustiness. The controlled aerosolization made possible with this setup occurs using energy inputs (may be characterized by aerosolization air velocity) that are within the ranges commonly found in occupational environments where nanomaterial powders are handled. This setup and its operating protocol are thus helpful for human exposure and risk assessment.

We designed and developed an effective nanopowder aerosolization setup and operating protocol. The system generated nanoparticle aerosols with stable number concentrations and size distributions for long durations, requiring only small quantities of test material (min. 200 mg).

系统创建从纳米粉体纳米稳定气溶胶

Nanoparticle aerosols released from nanopowders in workplaces are associated with human exposure and health risks. We developed a novel system, requiring ...

Plasmonic Trapping and Release of Nanoparticles in a Monitoring Environment

Plasmonic tweezers use surface plasmon polaritons to confine polarizable nanoscale objects. Among the various designs of plasmonic tweezers, only a few can observe immobilized particles. Moreover, a limited number of studies have experimentally measured the exertable forces on the particles. The designs can be classified as the protruding nanodisk type or the suppressed nanohole type. For the latter, microscopic observation is extremely challenging. In this paper, a new plasmonic tweezer system is introduced to monitor particles, both in directions parallel and orthogonal to the symmetric axis of a plasmonic nanohole structure. This feature enables us to observe the movement of each particle near the rim of the nanohole. Furthermore, we can quantitatively estimate the maximal trapping forces using a new fluidic channel.

A microchip fabrication process that incorporates plasmonic tweezers is presented here. The microchip enables the imaging of a trapped particle to measure maximal trapping forces.

电浆捕获和纳米粒子的释放在监控环境

Plasmonic tweezers use surface plasmon polaritons to confine polarizable nanoscale objects. Among the various designs of plasmonic tweezers, only a few ...

Subsurface Defect Localization by Structured Heating Using Laser Projected Photothermal Thermography

The presented method is used to locate subsurface defects oriented perpendicularly to the surface. To achieve this, we create destructively interfering thermal wave fields that are disturbed by the defect. This effect is measured and used to locate the defect. We form the destructively interfering wave fields by using a modified projector. The original light engine of the projector is replaced with a fiber-coupled high-power diode laser. Its beam is shaped and aligned to the projector&#39;s spatial light modulator and optimized for optimal optical throughput and homogeneous projection by first characterizing the beam profile, and, second, correcting it mechanically and numerically. A high-performance infrared (IR) camera is set up according to the tight geometrical situation (including corrections of the geometrical image distortions) and the requirement to detect weak temperature oscillations at the sample surface. Data acquisition can be performed once a synchronization between the individual thermal wave field sources, the scanning stage, and the IR camera is established by using a dedicated experimental setup which needs to be tuned to the specific material being investigated. During data post-processing, the relevant information on the presence of a defect below the surface of the sample is extracted. It is retrieved from the oscillating part of the acquired thermal radiation coming from the so-called depletion line of the sample surface. The exact location of the defect is deduced from the analysis of the spatial-temporal shape of these oscillations in a final step. The method is reference-free and very sensitive to changes within the thermal wave field. So far, the method has been tested with steel samples but is applicable to different materials as well, in particular to temperature sensitive materials.

This method aims at locating vertical subsurface defects. Here, we couple a laser with a spatial light modulator and trigger its video input to heat a sample surface deterministically with two anti-phased modulated lines while acquiring highly resolved thermal images. The defect position is retrieved from evaluating thermal wave interference minima.

使用激光投射光热法构造加热的地下缺陷定位

The presented method is used to locate subsurface defects oriented perpendicularly to the surface. To achieve this, we create destructively interfering ...

Experimental Implementation of a New Composite Fabrication Method: Exposing Bare Fibers on the Composite Surface by the Soft Layer Method

The bipolar plate is a key component in proton exchange membrane fuel cells (PEMFCs) and vanadium redox flow batteries (VRFBs). It is a multi-functional component that should have high electrical conductivity, high mechanical properties, and high productivity.
In this regard, a carbon fiber/epoxy resin composite can be an ideal material to replace the conventional graphite bipolar plate, which often leads to the catastrophic failure of the entire system because of its inherent brittleness. Though the carbon/epoxy composite has high mechanical properties and is easy to manufacture, the electrical conductivity in the through-thickness direction is poor because of the resin-rich layer that forms on its surface. Therefore, an expanded graphite coating was adopted to solve the electrical conductivity issue. However, the expanded graphite coating not only increases the manufacturing costs but also has poor mechanical properties.
In this study, a method to expose fibers on the composite surface is demonstrated. There are currently many methods that can expose fibers by surface treatment after the fabrication of the composite. This new method, however, does not require surface treatment because the fibers are exposed during the manufacture of the composite. By exposing bare carbon fibers on the surface, the electrical conductivity and mechanical strength of the composite are increased drastically.

A protocol to expose bare fibers on the composite surface by eliminating resin rich area is presented. The fibers are exposed during fabrication of the composites, not by the post surface treatment. The exposed carbon composites exhibit high electrical conductivity in the through-thickness direction and high mechanical property.

一种新的复合制备方法的实验实现: 用软层法对复合材料表面裸露纤维进行曝光

The bipolar plate is a key component in proton exchange membrane fuel cells (PEMFCs) and vanadium redox flow batteries (VRFBs). It is a multi-functional ...

A 3D-printed Chamber for Organic Optoelectronic Device Degradation Testing

In this manuscript, we outline the manufacture of a small, portable, easy-to-use atmospheric chamber for organic and perovskite optoelectronic devices, using 3D-printing. As these types of devices are sensitive to moisture and oxygen, such a chamber can aid researchers in characterizing the electronic and stability properties. The chamber is intended to be used as a temporary, reusable, and stable environment with controlled properties (including humidity, gas introduction, and temperature). It can be used to protect air-sensitive materials or to expose them to contaminants in a controlled way for degradation studies. To characterize the properties of the chamber, we outline a simple procedure to determine the water vapor transmission rate (WVTR) using relative humidity as measured by a standard humidity sensor. This standard operating procedure, using a 50% infill density of polylactic acid (PLA), results in a chamber that can be used for weeks without any significant loss of device properties. The versatility and ease of use of the chamber allows it to be adapted to any characterization condition that requires a compact-controlled atmosphere.

Here, we present a protocol for the design, manufacture, and use of a simple, versatile 3D-printed and controlled atmospheric chamber for the optical and electrical characterization of air-sensitive organic optoelectronic devices.

用于有机光电器件降解测试的3维印制腔

In this manuscript, we outline the manufacture of a small, portable, easy-to-use atmospheric chamber for organic and perovskite optoelectronic devices, ...