涉及个人行走的实验与运动和姿势分析实验室鲁汶（MALL）25合作进行的。他们的合作和支持表示感谢。

所有的程序是由鲁汶大学附属医院的伦理委员会批准，每个受试者参与前发表了书面知情同意书。 1. 3D运动跟踪:配置和数据采集<ol><li>确保各个传感器完全充电（ 图1A）。此步骤需要约1小时，但可以在之前的实际测量的日子进行。按照制造商的计费协议。 </li><li> MT管理器-数据采集2: <ol><li>启用与传感器的无线连接，并指定所需的采样率（无线配置&gt;启用所有无线大师）。 注意:为了允许行人行为的精确表征，至少60赫兹的采样率被劝告。各个传感器记录的3D线性加速度，角速度（大地）磁场和大气压力的数据。 </li><li>激活操作模式并开始测量模式:使与传感器动作迟缓约1分钟（无线配置&gt;上的所有无线大师开始测量）。 </li><li>显示所有有源传感器（视图&gt;显示&gt;惯性数据）的惯性与磁性数据。确保，而静止的，传感器的取向不机会。 注意:固定传感器的改变方向将指示磁干扰的环境，并且由此不准确的定向信息。 </li></ol></li><li>方向复位:应用对象/航向复位（对象/航向复位&gt;复位方位）来定义实验（ 图1B）2的全球参考框架。 </li><li>放置在尽可能靠近到位于第五腰椎（ 图1C）的水平质体中心（COM）的传感器。紧紧地和稳健拧紧单个传感器上带有S每个参与者pecially设计的点击式全身吊带（ 图1C）。 </li><li>按要求记录的数据。 </li><li>负载的利息（打开文件）的记录，指定导出设置（工具&gt;首选项&gt;出口商），并导出加速度（和方向矩阵）的数据进行后续分析2（文件&gt;导出）。 </li></ol> 2.力板:安装和配置注意:本步骤讨论的力板的应用程序注册的GRFS。在该行走/跑步者参与的情况下，一系列的力板或仪表跑步机将被用于注册由后续步骤3中感生的装载，协议本身是类似的。 <ol><li>确保力板牢固地固定在试验室地上（ 图2）。 </li><li>配置设备和采集设置4（NDI打开捕捉&gt;数据&gt;设备设置&gt; SettiNGS）。选择适当的"增益"和"采样率"。配置和检查外部触发设置，如果需要的话4。 <ol><li>选择在根据所希望的精度和所涉及的加载类型的增益和采样率。用于本申请中，使用128（最大挤压力4,879 N）和采样率200Hz的增益。 </li></ol></li><li>启动和结束与空力盘每次试验:去皮力板时，空（NDI打开捕捉&gt;数据&gt;设备设置&gt;设置&gt;去皮）。 </li><li>为了验证目的:将一个已知重量之前测力板的顶部，每次试验后。 注意:在本申请5kg的质量被使用，但是，使用另一个公知的硬质的质量（&gt; 2的千克）可以同等服务于这个验证测试。 </li><li>按要求记录并保存数据GRF。导出GRFS供后续分析4。 </li></ol> 3.结构Accele的测量口粮注意:本步骤的目的是在结构上的一个或多个相关位置以收集结构振动。本申请使用GeoSIG GMS录像机（ 图3）以注册结构加速度。其他类型的传感器与所涉及的应用适当的特点，可同样适用。 <ol><li>确保各个传感器完全充电。此步骤可能需要几个小时，但可以在之前的实际测量的日子进行。按照制造商的计费协议。 </li><li>安装在主结构的所希望的位置的传感器:水平传感器和，如果需要的话，提供适当的固定到主结构（ 例如，通过利用磁铁）。 注意:给定个体的高质量GMS录像机（&gt; 6千克）和所涉及的低频振荡（&lt;6赫兹），没有额外的固定在此情况下是必要的。 </li><li>对于地理DAS数据采集5:配置并启用GMS无线网络和连接与传感器5。检查时间设置和同步设置（如有必要）（右键点击传感器&gt;更多信息）。 </li><li>上的所需位置的传感器定位和在与全球基准帧协议他们的水平。 </li><li>对于GeoDAS数据采集5:导出记录的数据供后续分析（右键点击传感器&gt;仪器控制&gt;发送一个请求&gt;用户请求&gt; GETEVT 5）。 </li></ol> 4.实验受控的实验室环境<ol><li>配置/设置3D运动跟踪（在第1节讨论）。 </li><li>配置/设置力板（在第2节讨论）。 </li><li>在操作过程中:目视检查实时两个无线惯性传感器和力板的测量，以验证他们的操作模式。 </li><li>问particip蚂蚁跨上力板和静置至少30秒:这允许识别每个单独的重量。 </li><li>配置节拍器信号:选择想要的节奏， 也就是说，根本迫使频率。 注:节拍器信号可以使用免费在线或智能手机应用程序可轻松配置。 </li><li>开始记录的力板和无线惯性传感器两者的数据。 </li><li>请参与者以启动所需的活动:行走，跳跃或于节拍器信号指示的（目标起搏）率上下摆动（ 见图4）。 </li><li>记录加载循环， 例如，步骤，跳跃或摆动周期所选择的数量。请参与者下车力板。 注意:为了验证目的，建议考虑在这些条件下卸载一些额外的录制时间。在文献中，有关于要求为C的最小数量加载循环没有明确的共识haracterize周期到周期变率6。根据经验和在提出的工作[6]，这里提出的研究认为，连续的60个周期，由此在第一和最后五个加载循环被排除在进一步的分析中排除在试验的开始和结束的装载模式的不规则性。 </li></ol> 5.实验原位 <ol><li>配置/安装跟踪参与者的运动3D惯性传感器网络（见第2和图5）。 </li><li>配置/安装程序在注册结构加速度无线加速度计的大湄公河次区域网络（见第4节）。 </li><li>在操作过程中:（目视）检查无线惯性传感器的实时测量，以验证他们的操作模式。 </li><li>定义明确的协议，它允许如果需要的话所涉及的测量系统同步。 注:这一步是必要的时候介入数据采集​​系统不允许直接同步由于缺少一个触发器或公共信道的。后者是用于现场试验（5.1和5.2）在所施加的所述无线测量系统的情况。因此，一个明确的协议已经通过了网站，允许对数据集离线同步。在本申请中，所涉及的测量系统通过一个相同的事件的登记， 也就是说，冲击同步，在开始和每次试验结束时，由每个所涉及测量系统中的至少一个传感器记录。正确对齐时间向量通过这些事件的离线对准随后获得。 </li><li>配置节拍器信号: 在原位 ，使用扩音器的扩增是必需的目标节拍。 </li><li>收集足够数量的试验，以检查试验的可重复性。根据经验，作者建议记录至少3个，或优选4，TRIALS。 </li></ol> 6.数据分析<ol><li>预处理的要求所涉及的设备的原始数据:应用适当的过滤器，以除去不需要的影响，例如不相关的高频贡献和测量噪声，并根据制造商的协议保留有关的时间窗口。 注意:滤波特性应根据应用来选择。在本研究中，在MATLAB信号处理工具箱7被施加到以20Hz进行的低通带的截止频率滤波对于所有涉及的信号。 </li><li>每个参与者:计算离散傅立叶利用MATLAB信号处理工具箱7 Com的注册加速度的变换，并确定平均载荷的频率在所获得的频谱中的基波的主峰的频率。 </li><li>识别时间的负载周期中的任何两个名义上相同的事件之间S使用[3]或PediVib MATLAB工具箱8 lc_timing工具的详细方法<ol><li>加载数据载体（lc_timing&gt;加载）。 </li><li>指定的采样率和估算的平均加载频率。指定相关的时间窗，如果需要的话。保存标称相同事件的确定时间， 即负载周期（lc_timing&gt;保存）。 </li></ol></li><li>计算平均加载频率作为在随后的负载循环之间的平均时间（如在6.3标识）的倒数。 </li><li>在实验室的实验中:应用在6.3为所得地面反作用力和在每个单独的COM注册的加速度详述的方法。 注意:此步骤可作为验证的程序适用于其中GRFS不能直接测得的原位实验。中详述的方法[3]展示了如何的时变起搏频率行人可以通过表征个体的COM附近注册的加速度和随之而来的GRFS之间的关系来确定。 </li><li> 原位实验:应用在6.3在每个单独的COM注册的加速度详述的方法。 </li></ol>结构响应的7模拟与分析注意:用MATLAB 7被执行的随后的步骤。结构响应使用PediVib工具箱，由作者8开发的MATLAB工具箱（ 图6）计算:人类活动引起的力通过广义负荷模型的应用决定由李等人定义9（步行）和巴赫曼。 等 1（跳跃，奔跑和防暴加载），和结构模型中的模态被配制坐标10。随附的手册包括教程，清楚地表明了以下步骤。 <ol><li>结构响应仿真<ol><li>定义测试结构的模态参数:固有频率，模态阻尼比，质量标准化模式的位移，配合相应的节点（PediVib&gt;结构参数&gt;新建）。目视检查模式输入信息（PediVib&gt;结构参数&gt;查看）。 </li><li>定义行人的特点和相应的感应负载:负载类型，重量，行走路径/位置，平均起搏频率，每个负载周期的开始（PediVib&gt;单人行&gt;新建）。运行并保存所涉及的参与者模拟结构响应。目视检查的结果（PediVib&gt;单人行&gt;查看）。 </li></ol></li><li>计算通过各个响应的叠加， 也就是，相应的矢量求和的总结构响应，并将结果与实测结构响应比较，例如，通过创建其中显示测量和模拟结构响应的数字。 </li></ol>

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The authors have nothing to disclose.

人体运动和由此产生GRFS通常用测力板的应用识别，仪表跑步机以及光学动作捕捉技术，如维科18和19 CODA。这些技术的应用是，然而，限制在实验室环境。在回答这个缺点，那允许"自然"的人的行为测量过多次反复，不间断循环创新技术的潜力正在调查20。替代技术包括使用压敏鞋垫系统21或仪表鞋22。这些系统允许接触力的结构上直接测量，但一般只产生垂...

通过效率的经济需求和（新）材料，建筑师和工程师正在推动的界限越来越长建，更高，更轻的结构，实力的不断增强推动。通常情况下，重量轻，修长的结构具有说谎的人类共同的活动，如散步，跑步或跳跃的主导频谱中的一个或多个自然频率。可能是受到（近）共振激发，他们往往过分响应人体运动，造成1令人不安的，甚至有害的振动。这些细长和轻型结构，振动适用性日益受到关注，经常构成重要的设计要求的问题。 人体运动，将所得地面反作用力（GRFS）通常实验在实验室条件下确定的。目前，设计人员不得不依赖 - 假设什么是"保守" - 当量的1-OAD模型，从单人的测力放大的。随着设计通过在高密度人群的动态性能的约束，强大的需求存在当前可用负荷模型的验证和完善。 本协议采用了行人的自然运动的特征三维惯性运动跟踪技术。它示出该信息如何可以被用来定义行人以及相应的感应负载之间的相关性。在随后的步骤中，其特征行人行为用于数值模拟的感应结构响应。与登记的结构响应比较允许量化的不明人-结构交互的现象， 例如 ，效果，所添加的阻尼因行人的存在。该方法是用于说明全尺度试验一个真正的人行桥，其中结构响应和面值的议案ticipants同时注册。

<table border="0" cellpadding="0" cellspacing="0" width="1081">
	<tbody>
		<tr height="65">
			<td height="65" style="height:65px;width:301px;">MTw Development Kit + MT Manager Software</td>
			<td style="width:107px;">Xsens</td>
			<td style="width:280px;">MTW-38A70G20-1</td>
			<td style="width:393px;">Development kit with wireless, highly accurate, small and lightweight 3D human motion trackers and accompanying click-in full body straps.</td>
		</tr>
		<tr height="65">
			<td height="65" style="height:65px;width:301px;">True Impulse Kinetic Measurement System + NDI Open Capture Data Acquisition and Visualization System</td>
			<td style="width:107px;">NDI Northern Digital Inc.</td>
			<td style="width:280px;">791028</td>
			<td style="width:393px;">TrueImpulse measures reaction forces exerted by humans during a wide variety of activities.</td>
		</tr>
		<tr height="65">
			<td height="65" style="height:65px;width:301px;">GMS-24</td>
			<td style="width:107px;">GeoSIG Ltd</td>
			<td style="width:280px;">Rev. 03.08.2010</td>
			<td style="width:393px;">(Wireless) accelerometers to register the structural vibrations.</td>
		</tr>
		<tr height="65">
			<td height="65" style="height:65px;width:301px;">GeoDAS GeoSIG Data Acquisition System</td>
			<td style="width:107px;">GeoSIG Ltd</td>
			<td style="width:280px;">Rev. 03.08.2010</td>
			<td style="width:393px;">Graphical MS Windows application running under Windows 9x/NT/2000, providing a software interface between users and GeoSIG recorders GSR/GCR/GBV/GT.</td>
		</tr>
		<tr height="65">
			<td height="65" style="height:65px;width:301px;">PediVib toolbox</td>
			<td style="width:107px;">KU Leuven</td>
			<td style="width:280px;">/</td>
			<td style="width:393px;">Software interface/toolbox to simulate the structural vibrations induced by pedestrians.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:301px;">Metronome</td>
			<td style="width:107px;">/</td>
			<td style="width:280px;">/</td>
			<td style="width:393px;">A device to indicate the targetted pacing rate of the activity (free applications are available online for pc/laptop/smartphone).</td>
		</tr>
	</tbody>
</table>

simulation of human-induced vibrations based on the characterized in-field pedestrian behavior

对于纤细轻巧的结构，振动舒适度是越来越多的关注，往往构成重要的设计要求的问题。随着设计的人类活动引起的载荷作用下管辖的动态性能，强大的需求存在的现有负荷模型验证和完善。本贡献使用的内场行人行为的表征三维惯性运动跟踪技术。该技术是在实验室的实验第一次测试与相应的地面反作用力的同时注册。实验包括散步的人，以及有节奏的人类活动，如跳跃和上下摆动。它表明，在登记的运动允许活动的时变起搏率的识别。与人的重量，并在文献中可获得的广义的力模型的应用一起，所识别的时间变起搏率允许为characterize人类造成的负荷。此外，无线运动跟踪器之间的时间同步允许识别所述参与者之间的同步速率。接着，该技术被用在其中的人和感应结构振动的两者的运动被登记一个真实天桥。它示出了其特征场行人行为如何可以适用于模拟的感应结构响应。它表明， 在确定原地踱步率和同步率构成了人类引起的负荷的仿真和验证的必要投入。拟议的方法的主要潜在应用是人类与结构相互作用现象的估计和合适的模型对实际交通状况行人之间的相关性的发展。

首先，示出的个人的COM附近登记的加速度如何可以用来表征结果GRFS。其结果在这里讨论了行走个别3。完全可比观测制成时有节奏的人类活动， 即，跳跃和上下摆动，被考虑。 图7A和7B示出了连续的垂直脚的力的振幅谱和步行的COM附近注册相应加速度水平定性高度相似即，在形状和频率。该活动的平均起搏速率可以被标识为?...

Watch this Scientific Journal Video about Simulation of Human-induced Vibrations Based on the Characterized In-field Pedestrian Behavior at JoVE.com

Simulation of Human-induced Vibrations Based on the Characterized In-field Pedestrian Behavior

的协议，提出了在现场行人行为的特征和所产生的结构响应的模拟。现场试验表明， 在确定原地踱步参与者之间的速率和同步率构成了人类引起的负荷的仿真和验证的必要投入。

基于该特征场行人行为人类引起的振动模拟

For slender and lightweight structures, vibration serviceability is a matter of growing concern, often constituting the critical design requirement. With ...

simulation-human-induced-vibrations-based-on-characterized-field

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8.7K 次观看.  KU Leuven. 的协议，提出了在现场行人行为的特征和所产生的结构响应的模拟。现场试验表明， 在确定原地踱步参与者之间的速率和同步率构成了人类引起的负荷的仿真和验证的必要投入。 

视频: Simulation of Human-induced Vibrations Based on the Characterized In-field Pedestrian Behavior

Simulation, Fabrication and Characterization of THz Metamaterial Absorbers

Metamaterials (MM), artificial materials engineered to have properties that may not be found in nature, have been widely explored since the first theoretical1 and experimental demonstration2 of their unique properties. MMs can provide a highly controllable electromagnetic response, and to date have been demonstrated in every technologically relevant spectral range including the optical3, near IR4, mid IR5 , THz6 , mm-wave7 , microwave8 and radio9 bands. Applications include perfect lenses10, sensors11, telecommunications12, invisibility cloaks13 and filters14,15. We have recently developed single band16, dual band17 and broadband18 THz metamaterial absorber devices capable of greater than 80% absorption at the resonance peak. The concept of a MM absorber is especially important at THz frequencies where it is difficult to find strong frequency selective THz absorbers19. In our MM absorber the THz radiation is absorbed in a thickness of ~ &lambda;/20, overcoming the thickness limitation of traditional quarter wavelength absorbers. MM absorbers naturally lend themselves to THz detection applications, such as thermal sensors, and if integrated with suitable THz sources (e.g. QCLs), could lead to compact, highly sensitive, low cost, real time THz imaging systems.

This protocol outlines the simulation, fabrication and characterization of THz metamaterial absorbers. Such absorbers, when coupled with an appropriate sensor, have applications in THz imaging and spectroscopy.

模拟，太赫兹超材料吸收器的制备与表征

Metamaterials (MM),  artificial materials engineered to have properties that may not be found in  nature, have been widely explored since the first ...

科研

工程学

Simulation of the Planetary Interior Differentiation Processes in the Laboratory

A planetary interior is under high-pressure and high-temperature conditions and it has a layered structure. There are two important processes that led to that layered structure, (1) percolation of liquid metal in a solid silicate matrix by planet differentiation, and (2) inner core crystallization by subsequent planet cooling. We conduct high-pressure and high-temperature experiments to simulate both processes in the laboratory. Formation of percolative planetary core depends on the efficiency of melt percolation, which is controlled by the dihedral (wetting) angle. The percolation simulation includes heating the sample at high pressure to a target temperature at which iron-sulfur alloy is molten while the silicate remains solid, and then determining the true dihedral angle to evaluate the style of liquid migration in a crystalline matrix by 3D visualization. The 3D volume rendering is achieved by slicing the recovered sample with a focused ion beam (FIB) and taking SEM image of each slice with a FIB/SEM crossbeam instrument. The second set of experiments is designed to understand the inner core crystallization and element distribution between the liquid outer core and solid inner core by determining the melting temperature and element partitioning at high pressure. The melting experiments are conducted in the multi-anvil apparatus up to 27 GPa and extended to higher pressure in the diamond-anvil cell with laser-heating. We have developed techniques to recover small heated samples by precision FIB milling and obtain high-resolution images of the laser-heated spot that show melting texture at high pressure. By analyzing the chemical compositions of the coexisting liquid and solid phases, we precisely determine the liquidus curve, providing necessary data to understand the inner core crystallization process.

The high-pressure and high-temperature experiments described here mimic planet interior differentiation processes. The processes are visualized and better understood by high-resolution 3D imaging and quantitative chemical analysis.

模拟行星内部分化过程中的实验室

A planetary interior is under high-pressure and high-temperature conditions and it has a layered structure. There are two important processes that led to ...

Laboratory Drop Towers for the Experimental Simulation of Dust-aggregate Collisions in the Early Solar System

For the purpose of investigating the evolution of dust aggregates in the early Solar System, we developed two vacuum drop towers in which fragile dust aggregates with sizes up to ~10 cm and porosities up to 70% can be collided. One of the drop towers is primarily used for very low impact speeds down to below 0.01 m/sec and makes use of a double release mechanism. Collisions are recorded in stereo-view by two high-speed cameras, which fall along the glass vacuum tube in the center-of-mass frame of the two dust aggregates. The other free-fall tower makes use of an electromagnetic accelerator that is capable of gently accelerating dust aggregates to up to 5 m/sec. In combination with the release of another dust aggregate to free fall, collision speeds up to ~10 m/sec can be achieved. Here, two fixed high-speed cameras record the collision events. In both drop towers, the dust aggregates are in free fall during the collision so that they are weightless and match the conditions in the early Solar System.

We present a technique to achieve low-velocity to intermediate-velocity collisions between fragile dust aggregates in the laboratory. For this purpose, two vacuum drop-tower setups have been developed that allow collision velocities between &#60;0.01 and ~10 m/sec. The collision events are recorded by high-speed imaging.

实验室落塔的粉尘聚集在碰撞早期太阳系的实验模拟

For the purpose of investigating the evolution of dust aggregates in the early Solar System, we developed two vacuum drop towers in which fragile dust ...

Selective Area Modification of Silicon Surface Wettability by Pulsed UV Laser Irradiation in Liquid Environment

The wettability of silicon (Si) is one of the important parameters in the technology of surface functionalization of this material and fabrication of biosensing devices. We report on a protocol of using KrF and ArF lasers irradiating Si (001) samples immersed in a liquid environment with low number of pulses and operating at moderately low pulse fluences to induce Si wettability modification. Wafers immersed for up to 4 hr in a 0.01% H2O2/H2O solution did not show measurable change in their initial contact angle (CA) ~75&#176;. However, the 500-pulse KrF and ArF lasers irradiation of such wafers in a microchamber filled with 0.01% H2O2/H2O solution at 250 and 65 mJ/cm2, respectively, has decreased the CA to near 15&#176;, indicating the formation of a superhydrophilic surface. The formation of OH-terminated Si (001), with no measurable change of the wafer&#8217;s surface morphology, has been confirmed by X-ray photoelectron spectroscopy and atomic force microscopy measurements. The selective area irradiated samples were then immersed in a biotin-conjugated fluorescein-stained nanospheres solution for 2 hr, resulting in a successful immobilization of the nanospheres in the non-irradiated area. This illustrates the potential of&#160;the method for selective area biofunctionalization and fabrication of advanced Si-based biosensing architectures. We also describe a similar protocol of irradiation of wafers immersed in methanol (CH3OH) using ArF laser operating at pulse fluence of 65 mJ/cm2 and in situ formation of a strongly hydrophobic surface of Si (001) with the CA of 103&#176;. The XPS results indicate ArF laser induced formation of Si&#8211;(OCH3)x compounds responsible for the observed hydrophobicity. However, no such compounds were found by XPS on the Si surface irradiated by KrF laser in methanol, demonstrating the inability of the KrF laser to photodissociate methanol and create -OCH3 radicals.

We report on a process of in situ alteration of HF treated Si (001) surface into a hydrophilic or hydrophobic state by irradiating samples in microfluidic chambers filled with&#160;H2O2/H2O solution (0.01%-0.5%) or methanol solutions using pulsed UV laser of a relative low pulse fluence.

硅表面润湿性的选择区域改性脉冲紫外激光照射在液体环境

The wettability of silicon (Si) is one of the important parameters in the technology of surface functionalization of this material and fabrication of ...

Knowledge Based Cloud FE Simulation of Sheet Metal Forming Processes

The use of Finite Element (FE) simulation software to adequately predict the outcome of sheet metal forming processes is crucial to enhancing the efficiency and lowering the development time of such processes, whilst reducing costs involved in trial-and-error prototyping. Recent focus on the substitution of steel components with aluminum alloy alternatives in the automotive and aerospace sectors has increased the need to simulate the forming behavior of such alloys for ever more complex component geometries. However these alloys, and in particular their high strength variants, exhibit limited formability at room temperature, and high temperature manufacturing technologies have been developed to form them. Consequently, advanced constitutive models are required to reflect the associated temperature and strain rate effects. Simulating such behavior is computationally very expensive using conventional FE simulation techniques.
This paper presents a novel Knowledge Based Cloud FE (KBC-FE) simulation technique that combines advanced material and friction models with conventional FE simulations in an efficient manner thus enhancing the capability of commercial simulation software packages. The application of these methods is demonstrated through two example case studies, namely: the prediction of a material's forming limit under hot stamping conditions, and the tool life prediction under multi-cycle loading conditions.

The following paper presents a novel FE simulation technique (KBC-FE), which reduces computational cost by performing simulations on a cloud computing environment, through the application of individual modules. Moreover, it establishes a seamless collaborative network between world leading scientists, enabling the integration of cutting edge knowledge modules into FE simulations.

板料成形过程的知识基于云的有限元模拟

The use of Finite Element (FE) simulation software to adequately predict the outcome of sheet metal forming processes is crucial to enhancing the ...

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.

弯曲对基于晶体的柔性有机单场效应晶体管的电气特性的影响

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

Preparation and High-temperature Anti-adhesion Behavior of a Slippery Surface on Stainless Steel

Anti-adhesion surfaces with high-temperature resistance have a wide application potential in electrosurgical instruments, engines, and pipelines. A typical anti-wetting superhydrophobic surface easily fails when exposed to a high-temperature liquid. Recently, Nepenthes-inspired slippery surfaces demonstrated a new way to solve the adhesion problem. A lubricant layer on the slippery surface can act as a barrier between the repelled materials and the surface structure. However, the slippery surfaces in previous studies rarely showed high-temperature resistance. Here, we describe a protocol for the preparation of slippery surfaces with high-temperature resistance. A photolithography-assisted method was used to fabricate pillar structures on stainless steel. By functionalizing the surface with saline, a slippery surface was prepared by adding silicone oil. The prepared slippery surface maintained the anti-wetting property for water, even when the surface was heated to 300 &#176;C. Also, the slippery surface exhibited great anti-adhesion effects on soft tissues at high temperatures. This type of slippery surface on stainless steel has applications in medical devices, mechanical equipment, etc.

Slippery surfaces provide a new way to solve the adhesion problem. This protocol describes how to fabricate slippery surfaces at high temperatures. The results demonstrate that the slippery surfaces showed anti-wetting for liquids and a remarkable anti-adhesion effect on soft tissues at high temperatures.

不锈钢滑面的制备及高温抗粘接性能研究

Anti-adhesion surfaces with high-temperature resistance have a wide application potential in electrosurgical instruments, engines, and pipelines. A ...

Study of Siphon Breaker Experiment and Simulation for a Research Reactor

Under the design conditions of a research reactor, the siphon phenomenon induced by pipe rupture can cause continuous outward flow of water. To prevent this outflow, a control device is required. A siphon breaker is a type of safety device that can be utilized to control the loss of coolant water effectively.
To analyze the characteristics of siphon breaking, a real-scale experiment was conducted. From the results of the experiment, it was found that there are several design factors that affect the siphon breaking phenomenon. Therefore, there is a need to develop a theoretical model capable of predicting and analyzing the siphon breaking phenomenon under various design conditions. Using the experimental data, it was possible to formulate a theoretical model that accurately predicts the progress and the result of the siphon breaking phenomenon. The established theoretical model is based on fluid mechanics and incorporates the Chisholm model to analyze two-phase flow. From Bernoulli&#39;s equation, the velocity, quantity, undershooting height, water level, pressure, friction coefficient, and factors related to the two-phase flow could be obtained or calculated. Moreover, to utilize the model established in this study, a siphon breaker analysis and design program was developed. The simulation program operates on the theoretical model basis and returns the result as a graph. The user can confirm the possibility of the siphon breaking by checking the shape of the graph. Furthermore, saving the entire simulation result is possible and it can be used as a resource for analyzing the real siphon breaking system.
In conclusion, the user can confirm the status of the siphon breaking and design the siphon breaker system using the program developed in this study.

The siphon breaking phenomenon was investigated experimentally and a theoretical model was proposed. A simulation program based on the theoretical model was developed and the results of the simulation program were compared with experimental results. It was concluded that the results of the simulation program matched the experimental results well.

研究堆虹吸断路器试验与仿真研究

Under the design conditions of a research reactor, the siphon phenomenon induced by pipe rupture can cause continuous outward flow of water. To prevent ...

Predicting Catalyst Extrudate Breakage Based on the Modulus of Rupture

The mechanical strength of extruded catalysts and their natural or forced breakage by either collision against a surface or by a compressive load in a fixed bed are important phenomena in catalyst technology. The mechanical strength of the catalyst is measured here by its bending strength or flexural strength. This technique is relatively new from the perspective of applying it to commercial catalysts of typical sizes used in the industry. Catalyst breakage by collision against a surface is measured after a fall of the extrudates through the ambient air in a vertical pipe. Quantifying the impact force is done theoretically by applying Newton's second law. Measurement of catalyst breakage due to stress in a fixed bed is done following the standard procedure of the bulk crush strength test. Novel here is the focus on measuring the reduction in the length to diameter ratio of the extrudates as a function of the stress.

Here we present a protocol to measure the modulus of rupture of an extruded catalyst and the breakage of said catalyst extrudates by collision against a surface or by compression in a fixed bed.

基于断裂模量的催化剂挤出断裂预测

The mechanical strength of extruded catalysts and their natural or forced breakage by either collision against a surface or by a compressive load in a ...

A 100 KW Class Applied-field Magnetoplasmadynamic Thruster

Applied-field magnetoplasmadynamic thrusters (AF-MPD thrusters) are hybrid accelerators in which electromagnetic and gas dynamic processes accelerate plasma to high speed; they have considerable potential for future space applications with the significant advantages of high specific impulse and thrust density. In this paper, we present a series of protocols for designing and manufacturing a 100 kW class of AF-MPD thruster with water-cooling structures, a 130 V maximum discharge voltage, a 800 A maximum discharge current, and a 0.25 T maximum strength of magnetic field. A hollow tantalum tungsten cathode acts as the only propellant inlet to inhibit the radial discharge, and it is positioned axially at the rear of the anode in order to relieve anode starvation. A cylindrical divergent copper anode is employed to decrease anode power deposition, where the length has been reduced to decrease the wall-plasma connecting area. Experiments utilized a vacuum system that can achieve a working vacuum of 0.01 Pa for a total propellant mass flow rate lower than 40 mg/s and a target thrust stand. The thruster tests were carried out to measure the effects of the working parameters such as propellant flow rates, the discharge current, and the strength of applied magnetic field on the performance and to allow appropriate analysis. The thruster could be operated continuously for significant periods of time with little erosion on the hollow cathode surface. The maximum power of the thruster is 100 kW, and the performance of this water-cooled configuration is comparable with that of thrusters reported in the literature.

The goal of this protocol is to introduce the design of a 100 kW class applied-field magnetoplasmadynamic thruster and relevant experimental methods.

一个100千瓦级的应用场磁等离子体动力学推进器

Applied-field magnetoplasmadynamic thrusters (AF-MPD thrusters) are hybrid accelerators in which electromagnetic and gas dynamic processes accelerate ...