冉涛要感谢美国商务部国家标准与技术研究院70NANB15H112的资助。Aaron M. Forster的资金是通过国会拨款给国家标准与技术研究所提供的。

1. 流变仪设置
注意:本节中的实验方案描述了运行流变学实验的基本步骤（适用于单独的电机-传感器流变仪或组合式电机-探头流变仪），包括准备设置、安装适当的几何形状、加载测试材料、设置实验程序、指定几何形状以及开始测试。提供了有关 OSP 操作的具体说明和说明。为了尽量减少探头中的热梯度，建议在操作前至少为流变仪供电 30 分钟。该协议中用于仪器控制和数据收集的流变仪软件在 材料表中进行了说明。有关流变仪规格，请参见 表 1 。
<ol><li>在设置流变仪之前，请在流变仪软件中启用正 交叠加 功能。在测试站上安装一个较低的铂电阻温度计（PRT），用于温度测量和环境控制装置。 注:将载物台抬高至最大高度以进行安装过程（图1a）。在安装环境控制设备之前，请安装正确的PRT。在安装过程中，请注意不要用环境控制装置撞击PRT。使用随附的扳手将环境控制设备固定在测试站上。</li>
	<li>安装双壁同心圆柱几何形状。<ol><li>正确组装内筒和外筒（图1b）以完成双壁杯配置。 注意:在组装杯子之前，请检查内筒上的 O 形圈状况（是否有裂缝、膨胀或其他损坏），并在需要时更换。</li>
		<li>将杯子插入环境控制设备并正确对齐几何形状。</li>
		<li>向下按下几何形状（杯子）以压缩弹簧加载的PRT，同时使用扭矩螺丝刀（固定0.56 N m）拧紧指旋螺钉。 注意: 要检查下部几何结构是否正确安装，请禁用电机电源，然后用手指旋转几何图形。如果下部几何形状在环境控制装置中自由旋转，则安装正确并继续下一步。如果它不能自由旋转，请按与前面步骤相反的顺序从测试站中卸下组件，然后重新安装下部几何形状。验证温度信号是否从较低的PRT接收到。默认情况变仪应自动识别温度传感器;如果没有，请在流变仪软件的温度控制选项中选择较低的 PRT 作为温度控制传感器源。</li>
		<li>将上部几何形状 （bob） 安装在传感器轴上。通过单击流变仪软件中传感器控制面板中的皮重传感器按钮或使用仪器触摸屏上"仪器"选项卡上的皮重和皮重正常值来去皮法向力和扭矩。流变仪的完整设置如图 1c 所示。</li>
		<li>通过从流变仪软件或仪器触摸屏单击间隙控制面板中的"零 夹具 "按钮，将上下几何形状之间的间隙归零。如果需要，执行几何质量校准。 注意: 检查制造商提供的几何文档，以查看刀具质量上限值是否可用。如果没有，请在此步骤结束时执行几何质量校准。按照屏幕上的说明执行上部工具质量校准。完成后，确认接受正确的新夹具质量。</li>
	</ol></li>
</ol>2. 加载测试材料
<ol><li>抬起载物台以提供足够的工作空间将测试材料装入杯中。</li>
	<li>使用移液管或刮刀将测试材料装入杯中。小心处理测试材料，以尽量减少空气夹带到流体中。 注意:要加载低粘度测试材料（例如，小于5 Pa s），请使用可调节体积的移液器（图2a）。填充几何形状的最小体积可以在流变仪软件中"实验"面板下的几何信息中找到。目前可用的OSP几何形状所需的近似体积，即0.5 mm和1.0 mm环形间隙宽度，分别为32 mL和36 mL。对于加载更高粘度的测试材料（例如，高于5 Pa s），请使用刮刀或外置活塞式移液器（图2b）。由于难以对高粘度液体进行精确的体积控制，因此不建议根据流体体积进行微调，以装载高粘度液体。无论如何，预计在此步骤中会略微填充不足而不是过度填充。按照下一步操作，确保精确装载材料。</li>
	<li>将鲍勃降低到杯中，达到几何间隙设定点，然后提起以确定加载几何中的液位。目标是实现流体接触线略高于鲍勃上开口下边缘（约 2 mm）。 注意:此过程可能需要很长的等待时间才能达到所需的液位，因为几何形状的环形间隙宽度很小，并且所需的样品体积相对较大。等待时间主要取决于测试材料的粘度。例如，高粘度液体需要更长的时间才能流入气缸之间的间隙并完全润湿鲍勃表面。</li>
	<li>小心地将上部几何形状降低到流体中，以达到 8 mm 的几何间隙设定点。此过程如图 2c中的步骤1所示。等待几分钟，使鲍勃保持在间隙设置为 8 mm 的位置 （iii）。 注意: 当鲍勃端面接触流体时，降低鲍勃的向下速度。对于高粘度液体或屈服应力流体，请密切监测法向力读数，以防止传感器在此过程中过载。</li>
	<li>使用仪器的慢压摆速度垂直提升摆动到可以目视检查润湿流体接触管路的位置（图3）。接触线指示几何形状在间隙设定点处的液位。如果鲍勃上的线低于鲍勃的上端（鲍勃上开口的下边缘），则表明流体高度低于内缸高度，应在几何形状中添加额外的测试材料。</li>
	<li>小心地将鲍勃抬起到先前的装载位置，以留出足够的工作空间（ 图2c中的步骤2），并根据需要将额外数量的测试材料装入杯中。缓慢向上或向下移动摆动以避免气蚀。小心添加测试材料，以防止引入额外的气泡。</li>
	<li>将上部几何降低到流体中，并再次设置为最终几何间隙。重复步骤1和2（图2c），直到鲍勃上的润湿接触线在上鲍勃开口的下边缘上方约2毫米，如图 3a所示。还要检查鲍勃上开口的下边缘是否正确润湿（图3b）。将鲍勃移动到几何间隙设定点，让测试材料松弛。 注意:等待时间取决于标准材料的粘度。例如，对于 1 Pa s 的液体，15 分钟的等待时间就足够了;而对于 100 Pa s 的液体，需要更长的等待时间（4 小时）。此过程如图 2c中的步骤3所示。完整的样品上样过程如图 2所示。高粘度流体需要较长的时间，并且难以装载。为了减少等待时间，将温度升高几度可能有助于促进粘性校准液流动。</li>
</ol>3. 运行粘度校准测量
注意:本文提供的校准协议特定于应用于OSP技术的最终效应因素。这不包括常规校准或验证检查，包括扭矩和法向力校准、相位角检查、PDMS 检查等。由各个流变仪制造商推荐。这些程序应在本文件的校准方案之前执行。读者应参考流变仪制造商的用户手册，了解执行常规校准或检查的程序。该协议中使用的有机硅粘度标准液在 材料表中注明。
<ol><li>指定几何图形 注意: 在设置实验之前，请确保在流变仪软件中选择正确的几何形状。对于首次使用，请按照以下步骤在流变仪软件中创建新的正交双壁同心圆柱几何形状。<ol><li>添加新的正交双壁同心圆柱几何图形。</li>
		<li>输入几何图形的尺寸，如 表 2 所示。 注意:数字及其相应的符号刻在鲍勃和杯子上。此处使用的实验几何形状的工作间隙为 8 mm，但应由制造商指定。因此，内筒高度等于（浸入高度+ 8毫米）。</li>
	</ol></li>
	<li>指定几何常量。用适当的值填充几何惯性和几何质量字段。为最终效应因子和正交最终效应因子输入 1.00。 注意:制造商指定的 0.5 mm 和 1.0 mm 间隙 OSP 几何形状的几何惯量分别为 15.5 μN m s 2 和 10.3 μN ms 2。确保输入了正确的上部几何体量值。此值可以在制造商提供的几何文档中找到。或者，在几何校准选项卡（协议步骤1.2.5）下执行几何质量校准，并确认应用了正确的新夹具质量。默认的最终效应因子 （C L） 为 1.065，正交的最终效应因子 （CLo） 为 1.04。将两个字段都更改为 1.00。应力常数是根据尺寸和最终效应系数自动计算的。应变常数仅由几何尺寸确定（表达式在以前的工作18 中提供）。尺寸的定义如表2所示，如图4所示。（初级）应力常数 K τ 和正交（线性）应力常数 Kτο 的表达式为: <img alt="Equation 1" src="/files/ftp_upload/61965/61965equ01.jpg"> <img alt="Equation 2" src="/files/ftp_upload/61965/61965equ02.jpg"></li>
</ol>4. 稳态剪切速率扫描测试
注意:粘度校准测量在主要方向或正交方向上独立执行，以校准C L或CLo。对于主要方向，通过执行剪切速率扫描测试来测量稳定的剪切粘度。对于正交方向，通过执行正交频率扫描测试来测量动态复数粘度。
<ol><li>将样品在25°C下调节15分钟，以使测试材料达到热平衡。 注意:校准测量是在报告标准液体认证粘度的温度下进行的，即25°C。 读数仪可以使用适合其牛顿标准液体的不同测试温度。建议使用平衡时间或浸泡时间，即15分钟，以确保环境控制装置、几何形状和样品达到热平衡。</li>
	<li>在流变仪软件的实验程序下选择流动扫描测试。在环境控制下将测试温度设置为25°C。</li>
	<li>指定剪切速率范围从 0.01 s−1 到 100.0 s−1 ，并以每十进程 10 个点对数记录数据。启用自动稳态确定。 注意:此处使用的剪切速率范围基于仪器扭矩灵敏度限值（表1）和测量液体。例如，对于较高粘度的液体（例如，300 Pa s），可以使用10-4 s-1至1 s-1的较低剪切速率范围，反之亦然。</li>
	<li>从流变仪软件开始实验。</li>
</ol>5. 正交扫频测试
<ol><li>从流变仪软件中的探头控制面板将法向力传感器设置为 FRT 模式。 注意: 法向力传感器的默认传感器设置是此独立电机传感器流变仪的弹簧模式。在OSP操作中，法向力传感器作为应力控制或电机-传感器组合流变仪运行，以施加轴向变形，同时测量轴向力。法向力传感器必须设置为FRT模式才能执行OSP测试。</li>
	<li>将样品在25°C下调节15分钟以确保热平衡。</li>
	<li>在流变仪软件的实验程序下选择正交频率扫描测试。将测试温度设置为25°C。</li>
	<li>指定所需的法向应变，并输入 0.0 s−1 作为旋转方向上的剪切速率。 注意: 最大法向应变（轴向应变幅度）取决于 OSP 几何形状的间隙宽度，并受流变仪的最大正交振荡位移（即 50 μm）的限制（表 1）。</li>
	<li>以对数方式指定 0.1 到 40 rad/s 的角度频率范围，每十进程 10 个点。 注意:此处使用的角频率范围是基于仪器轴向频率灵敏度限制（表 1）和间隙载荷条件18 的 OSP 操作的推荐范围。有关更多详细信息，请参阅 "讨论 "部分。</li>
	<li>从流变仪软件开始实验。</li>
</ol>6. 执行分析
<ol><li>确定主要最终影响因素<ol><li>将稳定剪切速率扫描结果（来自协议步骤4.4）导出为开放文件格式，例如.csv或.txt。</li>
		<li>在电子表格软件中计算适当剪切速率范围内报告粘度的平均值。 注意: 只有相应扭矩值高于制造指定限值的粘度数据才能用于计算平均粘度。平均粘度值定义为未校正的主粘度。</li>
		<li>使用平均粘度值找到主要最终效应因子。 注意:此处提供本节是为了显示流变仪软件的主要最终影响因子与直接粘度输出之间的关系的推导。根据实验数据计算最终因子的示例在代表性结果部分进行了演示。初级稳态剪切粘度是剪切应力τ与剪切速率<img alt="Equation" src="/files/ftp_upload/61965/7.png">的比值，这是根据扭矩M和旋转速度的原始信号Ω通过几何常数（K τ和Kγ）计算得出的。表达式由下式给出: <img alt="Equation 3" src="/files/ftp_upload/61965/61965equ03.jpg"> 其中 K τ 是主应力常数（公式 1），Kγ 是完全取决于几何尺寸的主应变常数。因此，将公式1代入公式3，计算出的主粘度或流变仪软件的输出粘度值与初级最终效应因子CL成反比（请注意，公式3中的所有其他变量都是几何常数或原始测量信号）: <img alt="Equation 4" src="/files/ftp_upload/61965/61965equ04.jpg"> 请注意，公式 3 是任何旋转流变测量的一般表达式，其中测量的粘度是根据原始数据（即扭矩和速度）通过取决于所用不同几何形状的应力和应变常数计算的，例如锥板、平行板、同心圆柱等。</li>
	</ol></li>
</ol>7. 正交端效应因子的确定
<ol><li>将正交频率扫描结果（来自协议步骤5.6）导出为开放文件格式，如.csv或.txt。</li>
	<li>在电子表格软件中计算报告的OSP复合物粘度在适当角频率范围内的平均值。 注意: 只有具有高于制造商指定限值的相应振荡力值的粘度数据才能用于计算平均粘度。平均粘度值定义为未校正的正交复合粘度。</li>
	<li>使用平均复粘度值找到正交最终效应因子。 注意:此处提供本节是为了显示流变仪软件输出的正交端效应因子与正交复数粘度之间的关系的推导。根据实验数据计算正交端因子的示例在代表性结果部分进行了演示。正交复黏度等于正交复剪切模<img alt="Equation 9" src="/files/ftp_upload/61965/8.png">量除以正交振荡频率ω<img alt="Equation" src="/files/ftp_upload/61965/1.png" style="font-size: 14px;">，通过振荡力F<img alt="Equation" src="/files/ftp_upload/61965/1.png" style="font-size: 14px;">、振荡位移θ<img alt="Equation" src="/files/ftp_upload/61965/1.png" style="font-size: 14px;">、频率ω<img alt="Equation" src="/files/ftp_upload/61965/1.png" style="font-size: 14px;">（这三者都是原始信号）和几何常数（K το和K γο）可以表示为下面的方程: <img alt="Equation 5" src="/files/ftp_upload/61965/61965equ05.jpg"> 其中 K το 是正交应力常数（公式 2），Kγο 是正交应变常数，仅与几何尺寸相关。因此，将公式2代入公式5，计算出的正交复数粘度或流变仪软件输出的OSP复数粘度值与正交端效应因子CLo成正比（请注意，公式5中的所有其他变量都是几何常数或原始测量信号）: <img alt="Equation 6" src="/files/ftp_upload/61965/61965equ06.jpg"> 请注意，公式5是任何线性运动测量的一般表达式，其中测量的复粘度是根据原始数据（即力、位移和频率）通过取决于所用几何形状的应力和应变常数计算的，例如锥板、平行板、同心圆柱等。</li>
</ol>8. 通过OSP测量进行粘度验证检查
注意:此步骤是使用从校准实验中获得的校准最终效应因子验证校正是否有效。
<ol><li>在几何常量下输入最终效应因子和正交最终效果因子的校准值，最初这些值设置为 1.00。应力常数自动更新，值如 表3所示。</li>
	<li>按照正交频率扫描测试中的步骤设置相同的实验程序。输入 1.0 s−1 作为剪切速率。</li>
	<li>开始实验。</li>
</ol>

<ol>
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I., Williams, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+orthogonal+superposition+of+simple+shearing+and+small-strain+oscillatory+motions.">On the orthogonal superposition of simple shearing and small-strain oscillatory motions.</a> Rheologica Acta. 10 (4), 528-538 (1971).</li><li>Schoukens, G., Mewis, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nonlinear+rheological+behaviour+and+shear-dependent+structure+in+colloidal+dispersions.">Nonlinear rheological behaviour and shear-dependent structure in colloidal dispersions.</a> Journal of Rheology. 22 (4), 381-394 (1978).</li><li>Zeegers, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+sensitive+dynamic+viscometer+for+measuring+the+complex+shear+modulus+in+a+steady+shear+flow+using+the+method+of+orthogonal+superposition.">A sensitive dynamic viscometer for measuring the complex shear modulus in a steady shear flow using the method of orthogonal superposition.</a> Rheologica Acta. 34 (6), 606-621 (1995).</li><li>Mewis, J., Schoukens, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical+spectroscopy+of+colloidal+dispersions.">Mechanical spectroscopy of colloidal dispersions.</a> Faraday Discussions of the Chemical Society. 65, 58-64 (1978).</li><li>Lin, N. Y. C., Ness, C., Cates, M. E., Sun, J., Cohen, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tunable+shear+thickening+in+suspensions.">Tunable shear thickening in suspensions.</a> Proceedings of the National Academy of Sciences. 113 (39), 10774-10778 (2016).</li><li>Gracia-Fern&#225;ndez, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simultaneous+application+of+electro+and+orthogonal+superposition+rheology+on+a+starch/silicone+oil+suspension.">Simultaneous application of electro and orthogonal superposition rheology on a starch/silicone oil suspension.</a> Journal of Rheology. 60 (1), 121-127 (2015).</li><li>Sung, S. H., Kim, S., Hendricks, J., Clasen, C., Ahn, K. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Orthogonal+superposition+rheometry+of+colloidal+gels:+time-shear+rate+superposition.">Orthogonal superposition rheometry of colloidal gels: time-shear rate superposition.</a> Soft Matter. 14 (42), 8651-8659 (2018).</li><li>Colombo, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Superposition+rheology+and+anisotropy+in+rheological+properties+of+sheared+colloidal+gels.">Superposition rheology and anisotropy in rheological properties of sheared colloidal gels.</a> Journal of Rheology. 61 (5), 1035-1048 (2017).</li><li>Jacob, A. R., Poulos, A. S., Kim, S., Vermant, J., Petekidis, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Convective+Cage+Release+in+Model+Colloidal+Glasses.">Convective Cage Release in Model Colloidal Glasses.</a> Physical Review Letters. 115 (21), 218301 (2015).</li><li>Jacob, A. R., Poulos, A. S., Semenov, A. N., Vermant, J., Petekidis, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+dynamics+of+concentrated+starlike+micelles:+A+superposition+rheometry+investigation+into+relaxation+mechanisms.">Flow dynamics of concentrated starlike micelles: A superposition rheometry investigation into relaxation mechanisms.</a> Journal of Rheology. 63 (4), 641-653 (2019).</li><li>Moghimi, E., Vermant, J., Petekidis, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Orthogonal+superposition+rheometry+of+model+colloidal+glasses+with+short-ranged+attractions.">Orthogonal superposition rheometry of model colloidal glasses with short-ranged attractions.</a> Journal of Rheology. 63 (4), 533-546 (2019).</li><li>Tao, R., Forster, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=End+effect+correction+for+orthogonal+small+strain+oscillatory+shear+in+a+rotational+shear+rheometer.">End effect correction for orthogonal small strain oscillatory shear in a rotational shear rheometer.</a> Rheologica Acta. 59 (2), 95-108 (2020).</li><li>Schrag, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deviation+of+velocity+gradient+profiles+from+the+"gap+loading"+and+"surface+loading"+limits+in+dynamic+simple+shear+experiments.">Deviation of velocity gradient profiles from the "gap loading" and "surface loading" limits in dynamic simple shear experiments.</a> Transactions of the Society of Rheology. 21 (3), 399-413 (1977).</li><li>Ewoldt, R. H., Johnston, M. T., Caretta, L. M., Spagnolie, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Complex Fluids in Biological Systems. Biological and Medical Physics, Biomedical Engineering. , 207-241 (2015).</li></ol>

本文中使用的程序的完整描述需要识别某些商业产品及其供应商。包含此类信息绝不应被解释为表明此类产品或供应商已获得NIST的认可或NIST的推荐，或者它们一定是所述目的的最佳材料，仪器，软件或供应商。

在该协议中，我们提出了一个详细的实验程序，用于使用牛顿流体进行粘度校准测量，用于具有双壁同心圆柱几何形状的商业正交叠加流变技术。校准因子，即初级端效应因子C L和正交端效应因子CLo，通过进行稳态剪切速率扫描和正交频率扫描测试独立确定。获得最终因子后，进行验证测试以检查校准结果。验证试验是在一次稳态剪切上叠加正交扫频试...

了解复杂流体的流变特性对于许多行业开发和制造可靠且可重复的产品至关重要1.这些"复杂流体"包括悬浮液、聚合物液体和泡沫，它们广泛存在于我们的日常生活中，例如个人护理产品、食品、化妆品和家用产品中。流变学或流动特性（例如粘度）是建立最终用途和可加工性性能指标的关键量，但流动特性与复杂流体中存在的微观结构相互关联。复杂流体与简单液体的一个突出特征是它们具有跨越多个长度尺度的不同微观结构2。这些微观结构很容易受到不同流动条件的影响，这反过来又会导致其宏观性质的变化。通过复杂流体响应流动和变形的非线性粘弹性行为来解锁这种结构-性能循环仍然是实验流变学家的一项具有挑战性的任务。
正交叠加 （OSP） 流变学3 是应对这一测量挑战的可靠技术。在该技术中，小振幅振荡剪切流正交地叠加到单向初级稳剪切流上，从而能够在施加的初级剪切流下同时测量粘弹性松弛谱。更具体地说，小振荡剪切扰动可以使用线性粘弹性4中的理论进行分析，而非线性流动条件则由初级稳剪切流实现。由于两个流场是正交的，因此没有耦合，因此扰动谱可以直接与初级非线性流5下微观结构的变化有关。这种先进的测量技术为阐明复杂流体中的结构-性能-加工关系提供了机会，以优化其配方、加工和应用。
现代OSP流变学的实施不是突然顿悟的结果;相反，它基于数十年来定制设备的开发。第一个定制的OSP设备可以追溯到1966年由Simmons6，此后进行了许多努力7，8，9，10。这些早期的定制设备存在许多缺点，例如对准问题、泵送流量效应（由于鲍勃的轴向运动以提供正交振荡）以及仪器灵敏度的限制。1997 年，Vermant 等人 3 在商用独立电机传感器流变仪上修改了力再平衡传感器 （FRT），这使得 OSP 测量流体的粘度范围比以前的设备更宽。这种修改使法向力再平衡传感器能够用作应力控制的流变仪，除了测量轴向力外，还可以施加轴向振荡。最近，OSP测量所需的几何形状，在Vermant的方法之后，已经发布了用于商用独立电机传感器流变仪的几何形状。
自从商业OSP流变学问世以来，人们越来越有兴趣将这种技术应用于各种复杂流体的研究。实例包括胶体悬浮液11，12、胶体凝胶13、14和玻璃15、16、17。虽然商用仪器的可用性促进了OSP研究，但与其他常规流变技术相比，复杂的OSP几何形状需要对测量有更深入的了解。OSP 流通池基于双壁同心圆筒（或库埃特）几何形状。它具有开放式顶部和开放式底部设计，使流体能够在环形间隙和储液罐之间来回流动。尽管制造商对几何设计进行了优化，但在进行OSP操作时，流体会遇到不均匀的流场，几何末端效应和残余泵送流量，所有这些都会引入大量的实验误差。我们之前的工作18报告了使用牛顿流体进行该技术的重要终效校正程序。为了获得正确的粘度结果，应在初级和正交方向上应用适当的最终效应因子。在该协议中，我们旨在为OSP流变技术提供详细的校准方法，并为减少测量误差的最佳实践提供建议。本文中描述的有关OSP几何设置，样品加载和OSP测试设置的程序应易于采用，并可转换为非牛顿流体测量。我们建议用户在对任何流体分类（牛顿或非牛顿）进行OSP测量之前，使用此处描述的校准程序来确定其应用的最终效应校正因子。我们注意到，以前没有报告过最终因素的校准程序。本文提供的实验方案还介绍了有关如何进行准确流变测量的分步指南和技巧，以及了解"原始"数据与"测量"数据的技术资源，流变仪用户可能会忽略这些数据。

<table><tbody><tr><td>Advanced Peltier System</td><td>TA Instruments</td><td>402500.901</td><td>Enviromental control device</td></tr><tr><td>ARES-G2 Rheometer</td><td>TA Instruments</td><td>401000.501</td><td>Rheometer</td></tr><tr><td>Brookfield Silicone Fluid, 12500cP</td><td>AMTEK Brookfield</td><td>12500 cps</td><td>Viscosity standard liquid</td></tr><tr><td>OSP Slotted Bob, 33 mm</td><td>TA Instruments</td><td>402796.902</td><td>Bob, upper geometry</td></tr><tr><td>OSP Slotted Double Gap Cup, 34 mm</td><td>TA Instruments</td><td>402782.901</td><td>Double wall cup, lower geometry</td></tr><tr><td>Pipette (1 &amp;ndash; 10 mL)</td><td>Eppendorf</td><td>3120000089</td><td>To load test materials</td></tr><tr><td>Pipette (100 &amp;ndash; 1,000 &amp;micro;L)</td><td>Eppendorf</td><td>3123000063</td><td>To load test materials</td></tr><tr><td>Pipette Tips (0.5 &amp;ndash; 10 mL)</td><td>Eppendorf</td><td>022492098</td><td>To load test materials</td></tr><tr><td>Pipette Tips (50 &amp;ndash; 1,000 &amp;micro;L)</td><td>Eppendorf</td><td>022491555</td><td>To load test materials</td></tr><tr><td>Spatula</td><td>VWR</td><td>82027-532</td><td>To load test materials</td></tr><tr><td>TRIOS</td><td>TA Instruments</td><td>v4.3.1.39215</td><td>Rheometer software</td></tr></tbody></table>

calibration procedures for orthogonal superposition rheology

正交叠加 （OSP） 流变学是一种先进的流变学技术，涉及将小振幅振荡剪切变形与初级剪切流正交叠加。该技术允许在非线性流动条件下测量复杂流体的结构动力学，这对于理解和预测各种复杂流体的性能非常重要。自 1960 年代以来，OSP 流变技术有着悠久的发展历史，主要是通过突出该技术力量的定制设备。OSP 技术现已商业化，可供流变学界使用。鉴于OSP几何形状的复杂设计和非理想流场，用户应了解测量误差的大小和来源。本研究介绍了使用牛顿流体的校准程序，其中包括减少测量误差的最佳实践建议。具体而言，提供了有关最终效应因子确定方法、样品填充程序以及确定适当测量范围（例如剪切速率、频率等）的详细信息。

在12.2 Pa s有机硅粘度标准液上进行粘度校准测量的代表性结果如图5和图6所示。请注意，校准运行的主要最终效应因子和正交最终效应因子均设置为 1.00。图5显示了双y轴图上的稳态剪切粘度和扭矩与剪切速率的函数关系。硅油为牛顿流体;正如预期的那样，获得了与施加的剪切速率无关的恒定粘度。测得的扭矩随着剪切速率的增加...

Watch this Scientific Journal Video about Calibration Procedures for Orthogonal Superposition Rheology at JoVE.com

Calibration Procedures for Orthogonal Superposition Rheology

我们为使用牛顿流体的商业正交叠加流变学技术提供了详细的校准协议，包括最终效应校正因子测定方法和减少实验误差的最佳实践建议。

正交叠加流变学校准程序

Orthogonal superposition (OSP) rheology is an advanced rheological technique that involves superimposing a small-amplitude oscillatory shear deformation ...

calibration-procedures-for-orthogonal-superposition-rheology

Universidad de Cartagena UDEC

Research

JoVE Journal

Engineering

2.0K 次观看.  National Institute of Standards and Technology. 我们为使用牛顿流体的商业正交叠加流变学技术提供了详细的校准协议，包括最终效应校正因子测定方法和减少实验误差的最佳实践建议。

视频: Calibration Procedures for Orthogonal Superposition Rheology

Measurement of the Rheology of Crude Oil in Equilibrium with CO2 at Reservoir Conditions

A rheometer system to measure the rheology of crude oil in equilibrium with carbon dioxide (CO2) at high temperatures and pressures is described. The system comprises a high-pressure rheometer which is connected to a circulation loop. The rheometer has a rotational flow-through measurement cell with two alternative geometries: coaxial cylinder and double gap. The circulation loop contains a mixer, to bring the crude oil sample into equilibrium with CO2, and a gear pump that transports the mixture from the mixer to the rheometer and recycles it back to the mixer. The CO2 and crude oil are brought to equilibrium by stirring and circulation and the rheology of the saturated mixture is measured by the rheometer. The system is used to measure the rheological properties of Zuata crude oil (and its toluene dilution) in equilibrium with CO2 at elevated pressures up to 220 bar and a temperature of 50 &#176;C. The results show that CO2 addition changes the oil rheology significantly, initially reducing the viscosity as the CO2 pressure is increased and then increasing the viscosity above a threshold pressure. The non-Newtonian response of the crude is also seen to change with the addition of CO2.

Measurement of the Rheology of Crude Oil in Equilibrium with CO2 at Reservoir Conditions

A method for measuring the rheology of crude oil in equilibrium with carbon dioxide at reservoir conditions is presented.

与CO平衡的原油流变学测量<sub&gt; 2</sub&gt;在水库条件

A rheometer system to measure the rheology of crude oil in equilibrium with carbon dioxide (CO2) at high temperatures and pressures is described. The ...

科研

环境科学

Dielectric RheoSANS &#8212; Simultaneous Interrogation of Impedance, Rheology and Small Angle Neutron Scattering of Complex Fluids

A procedure for the operation of a new dielectric RheoSANS instrument capable of simultaneous interrogation of the electrical, mechanical and microstructural properties of complex fluids is presented. The instrument consists of a Couette geometry contained within a modified forced convection oven mounted on a commercial rheometer. This instrument is available for use on the small angle neutron scattering (SANS) beamlines at the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR). The Couette geometry is machined to be transparent to neutrons and provides for measurement of the electrical properties and microstructural properties of a sample confined between titanium cylinders while the sample undergoes arbitrary deformation. Synchronization of these measurements is enabled through the use of a customizable program that monitors and controls the execution of predetermined experimental protocols. Described here is a protocol to perform a flow sweep experiment where the shear rate is logarithmically stepped from a maximum value to a minimum value holding at each step for a specified period of time while frequency dependent dielectric measurements are made. Representative results are shown from a sample consisting of a gel composed of carbon black aggregates dispersed in propylene carbonate. As the gel undergoes steady shear, the carbon black network is mechanically deformed, which causes an initial decrease in conductivity associated with the breaking of bonds comprising the carbon black network. However, at higher shear rates, the conductivity recovers associated with the onset of shear thickening. Overall, these results demonstrate the utility of the simultaneous measurement of the rheo-electro-microstructural properties of these suspensions using the dielectric RheoSANS geometry.

Here, we present a procedure for the measurement of simultaneous impedance, rheology and neutron scattering from soft matter materials under shear flow.

介电RheoSANS  - 阻抗，流变性和复杂流体的小角中子散射的同时拷问

A procedure for the operation of a new dielectric RheoSANS instrument capable of simultaneous interrogation of the electrical, mechanical and ...

工程学

Challenges in Rheological Characterization of Highly Concentrated Suspensions &#8212; A Case Study for Screen-printing Silver Pastes

A comprehensive rheological characterization of highly concentrated suspensions or pastes is mandatory for a targeted product development meeting the manifold requirements during processing and application of such complex fluids. In this investigation, measuring protocols for a conclusive assessment of different process relevant rheological parameters have been evaluated. This includes the determination of yield stress, viscosity, wall slip velocity, structural recovery after large deformation and elongation at break as well as tensile force during filament stretching.
The importance of concomitant video recordings during parallel-plate rotational rheometry for a significant determination of rheological quantities is demonstrated. The deformation profile and flow field at the sample edge can be determined using appropriate markers. Thus, measurement parameter settings and plate roughness values can be identified for which yield stress and viscosity measurements are possible. Slip velocity can be measured directly and measuring conditions at which plug flow, shear banding or sample spillover occur can be identified clearly. 
Video recordings further confirm that the change in shear moduli observed during three stage oscillatory shear tests with small deformation amplitude in stage I and III but large oscillation amplitude in stage II can be directly attributed to structural break down and recovery. For the pastes investigated here, the degree of irreversible, shear-induced structural change increases with increasing deformation amplitude in stage II until a saturation is reached at deformations corresponding to the crossover of G' and G'', but the irreversible damage is independent of the duration of large amplitude shear. 
A capillary breakup elongational rheometer and a tensile tester have been used to characterize deformation and breakup behavior of highly filled pastes in uniaxial elongation. Significant differences were observed in all experiments described above for two commercial screen-printing silver pastes used for front side metallization of Si-solar cells.

A protocol for a robust and application relevant rheological characterization of highly concentrated suspensions is presented. Silver pastes used for screen-printing application in solar cell production are employed as model systems.

挑战流变特性高度集中悬架 - 为例进行丝网印刷银浆

A comprehensive rheological characterization of highly concentrated suspensions or pastes is mandatory for a targeted product development meeting the ...

Longitudinal Measurement of Extracellular Matrix Rigidity in 3D Tumor Models Using Particle-tracking Microrheology

The mechanical microenvironment has been shown to act as a crucial regulator of tumor growth behavior and signaling, which is itself remodeled and modified as part of a set of complex, two-way mechanosensitive interactions. While the development of biologically-relevant 3D tumor models have facilitated mechanistic studies on the impact of matrix rheology on tumor growth, the inverse problem of mapping changes in the mechanical environment induced by tumors remains challenging. Here, we describe the implementation of particle-tracking microrheology (PTM) in conjunction with 3D models of pancreatic cancer as part of a robust and viable approach for longitudinally monitoring physical changes in the tumor microenvironment, in situ. The methodology described here integrates a system of preparing in vitro 3D models embedded in a model extracellular matrix (ECM) scaffold of Type I collagen with fluorescently labeled probes uniformly distributed for position- and time-dependent microrheology measurements throughout the specimen. In vitro tumors are plated and probed in parallel conditions using multiwell imaging plates. Drawing on established methods, videos of tracer probe movements are transformed via the Generalized Stokes Einstein Relation (GSER) to report the complex frequency-dependent viscoelastic shear modulus, G*(&#969;). Because this approach is imaging-based, mechanical characterization is also mapped onto large transmitted-light spatial fields to simultaneously report qualitative changes in 3D tumor size and phenotype. Representative results showing contrasting mechanical response in sub-regions associated with localized invasion-induced matrix degradation as well as system calibration, validation data are presented. Undesirable outcomes from common experimental errors and troubleshooting of these issues are also presented. The 96-well 3D culture plating format implemented in this protocol is conducive to correlation of microrheology measurements with therapeutic screening assays or molecular imaging to gain new insights into impact of treatments or biochemical stimuli on the mechanical microenvironment.

Particle-tracking microrheology can be used to non-destructively quantify and spatially map changes in extracellular matrix mechanical properties in 3D tumor models.

细胞外基质刚性三维肿瘤模型的纵向测量用粒子跟踪Microrheology

The mechanical microenvironment has been shown to act as a crucial regulator of tumor growth behavior and signaling, which is itself remodeled and ...

生物工程

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.

微流体和 Microrheology 相结合测定软物质在重复相变过程中的流变特性

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

Studying Large Amplitude Oscillatory Shear Response of Soft Materials

We investigate the sequence of physical processes exhibited during large amplitude oscillatory shearing (LAOS) of polyethylene oxide (PEO) in dimethyl sulfoxide (DMSO) and xanthan gum in water &#8212; two concentrated polymer solutions used as viscosifiers in foods, enhanced oil recovery, and soil remediation. Understanding the nonlinear rheological behavior of soft materials is important in the design and controlled manufacturing of many consumer products. It is shown how the response to LAOS of these polymer solutions can be interpreted in terms of a clear transition from linear viscoelasticity to viscoplastic deformation and back again during a period. The LAOS results are analyzed via the fully quantitative Sequence of Physical Processes (SPP) technique, using free MATLAB-based software. A detailed protocol of performing a LAOS measurement with a commercial rheometer, analyzing nonlinear stress responses with the freeware, and interpreting physical processes under LAOS is presented. It is further shown that, within the SPP framework, a LAOS response contains information regarding the linear viscoelasticity, the transient flow curves, and the critical strain responsible for the onset of nonlinearity.

We present a detailed protocol outlining how to perform nonlinear oscillatory shear rheology on soft materials, and how to run the SPP-LAOS analysis to understand the responses as a sequence of physical processes.

软材料大振幅振荡剪切响应的研究

We investigate the sequence of physical processes exhibited during large amplitude oscillatory shearing (LAOS) of polyethylene oxide (PEO) in dimethyl ...

Macro-Rheology Characterization of Gill Raker Mucus in the Silver Carp, Hypophthalmichthys molitrix

The silver carp, Hypophthalmichthys molitrix, is an invasive planktivorous filter feeder fish that infested the natural waterways of the upper Mississippi River basin due to its highly efficient filter feeding mechanism. The characteristic organs called gill rakers (GRs), found in many such filter feeders, facilitate the efficient filtration of food particles such as phytoplankton that are of a few microns in size.
The motivation to investigate the rheology of the GR mucus stems from our desire to understand its role in aiding the filter feeding process in the silver carp. The mucus-rich fluid, in a &#8216;thick and sticky&#8217; state may facilitate the adhesion of food particulates. The permeation and transport through the GR membrane are&#160;facilitated by the action of external shear forces that induce varying shear strain rates. Therefore, mucus rheology can provide a vital clue to the tremendous outcompeting nature of the silver carp within the pool of filter feeding fish. Based on this it was posited that GR mucus may provide an adhesive function to food particles and act as a transport vehicle to assist in the filter feeding process.
The main objective of the protocol is to determine the yield stress of the mucus, attributed to the minimum shear stress required to initiate flow at which irreversible plastic deformation is first observed across a structured viscoelastic material. Accordingly, rheological properties of the GR mucus, i.e., viscosity, storage, and loss moduli, were investigated for its non-Newtonian, shear-thinning nature using a rotational rheometer. &#160;
A protocol presented here is employed to analyze the rheological properties of mucus extracted from the gill rakers of a silver carp, fished at Hart Creek location of the Missouri River. The protocol aims to develop an effective strategy for rheological testing and material characterization of mucus assumed to be a structured viscoelastic material.

Macro-Rheology Characterization of Gill Raker Mucus in the Silver Carp, Hypophthalmichthys molitrix

This protocol presents a method to perform rheology characterization of mucus that resides on gill rakers (GRs) of the silver carp. Viscoelastic characteristics of GR-mucus, obtained by measuring viscosity, storage and loss moduli, are evaluated for the apparent yield stress to understand the filter feeding mechanism in GRs.

银鲤鱼中吉尔 · 拉克 · 穆库斯的宏观流变特征， 低语种米希里斯 · 莫利特里克斯

The silver carp, Hypophthalmichthys molitrix, is an invasive planktivorous filter feeder fish that infested the natural waterways of the upper Mississippi ...

Microtensiometer for Confocal Microscopy Visualization of Dynamic Interfaces

Adsorption of surface-active molecules to fluid-fluid interfaces is ubiquitous in nature. Characterizing these interfaces requires measuring surfactant adsorption rates, evaluating equilibrium surface tensions as a function of bulk surfactant concentration, and relating how surface tension changes with changes in the interfacial area following equilibration. Simultaneous visualization of the interface using fluorescence imaging with a high-speed confocal microscope allows the direct evaluation of structure-function relationships. In the capillary pressure microtensiometer (CPM), a hemispherical air bubble is pinned at the end of the capillary in a 1 mL volume liquid reservoir. The capillary pressure across the bubble interface is controlled via a commercial microfluidic flow controller that allows for model-based pressure, bubble curvature, or bubble area control based on the Laplace equation. Compared to previous techniques such as the Langmuir trough and pendant drop, the measurement and control precision and response time are greatly enhanced; capillary pressure variations can be applied and controlled in milliseconds. The dynamic response of the bubble interface is visualized via a second optical lens as the bubble expands and contracts. The bubble contour is fit to a circular profile to determine the bubble curvature radius, R, as well as any deviations from circularity that would invalidate the results. The Laplace equation is used to determine the dynamic surface tension of the interface. Following equilibration, small pressure oscillations can be imposed by the computer-controlled microfluidic pump to oscillate the bubble radius (frequencies of 0.001-100 cycles/min) to determine the dilatational modulus The overall dimensions of the system are sufficiently small that the microtensiometer fits under the lens of a high-speed confocal microscope allowing fluorescently tagged chemical species to be quantitatively tracked with submicron lateral resolution.

This manuscript describes the design and operation of a microtensiometer/confocal microscope to do simultaneous measurements of interfacial tension and surface dilatational rheology while visualizing the interfacial morphology. This provides the real-time construction of structure-property relationships of interfaces important in technology and physiology.

用于动态界面共聚焦显微镜可视化的微量天体测量仪

Adsorption of surface-active molecules to fluid-fluid interfaces is ubiquitous in nature. Characterizing these interfaces requires measuring surfactant ...

Characterizing Multiscale Mechanical Properties of Brain Tissue Using Atomic Force Microscopy, Impact Indentation, and Rheometry

To design and engineer materials inspired by the properties of the brain, whether for mechanical simulants or for tissue regeneration studies, the brain tissue itself must be well characterized at various length and time scales. Like many biological tissues, brain tissue exhibits a complex, hierarchical structure. However, in contrast to most other tissues, brain is of very low mechanical stiffness, with Young&#39;s elastic moduli E on the order of 100s of Pa. This low stiffness can present challenges to experimental characterization of key mechanical properties. Here, we demonstrate several mechanical characterization techniques that have been adapted to measure the elastic and viscoelastic properties of hydrated, compliant biological materials such as brain tissue, at different length scales and loading rates. At the microscale, we conduct creep-compliance and force relaxation experiments using atomic force microscope-enabled indentation. At the mesoscale, we perform impact indentation experiments using a pendulum-based instrumented indenter. At the macroscale, we conduct parallel plate rheometry to quantify the frequency dependent shear elastic moduli. We also discuss the challenges and limitations associated with each method. Together these techniques enable an in-depth mechanical characterization of brain tissue that can be used to better understand the structure of brain and to engineer bio-inspired materials.

We present a set of techniques to characterize the viscoelastic mechanical properties of brain at the micro-, meso-, and macro-scales.

表征使用原子力显微镜，冲击压痕和流变测定脑组织的多尺度力学性能

To design and engineer materials inspired by the properties of the brain, whether for mechanical simulants or for tissue regeneration studies, the brain ...

神经科学

Rapid Viscoelastic Characterization of Airway Mucus Using a Benchtop Rheometer

In muco-obstructive lung diseases (e.g., asthma, chronic obstructive pulmonary disease, cystic fibrosis) and other respiratory conditions (e.g., viral/bacterial infections), mucus biophysical properties are altered by goblet cell hypersecretion, airway dehydration, oxidative stress, and the presence of extracellular DNA. Previous studies showed that sputum viscoelasticity correlated with pulmonary function and that treatments affecting sputum rheology (e.g., mucolytics) can result in remarkable clinical benefits. In general, rheological measurements of non-Newtonian fluids employ elaborate, time-consuming approaches (e.g., parallel/cone-plate rheometers and/or microbead particle tracking) that require extensive training to perform the assay and interpret the data. This study tested the reliability, reproducibility, and sensitivity of Rheomuco, a user-friendly benchtop device that is designed to perform rapid measurements using dynamic oscillation with a shear-strain sweep to provide linear viscoelastic moduli (G&#39;, G&#34;, G*, and tan &#948;) and gel point characteristics (&#947;c&#160;and &#963;c) for clinical samples within 5 min. Device performance was validated using different concentrations of a mucus simulant, 8 MDa polyethylene oxide (PEO), and against traditional bulk rheology measurements. A clinical isolate harvested from an intubated patient with status asthmaticus (SA) was then assessed in triplicate measurements and the coefficient of variation between measurements is &#60;10%. Ex vivo use of a potent mucus reducing agent, TCEP, on SA mucus resulted in a five-fold decrease in elastic modulus and a change toward a more &#34;liquid-like&#34; behavior overall (e.g., higher tan &#948;). Together, these results demonstrate that the tested benchtop rheometer can make reliable measures of mucus viscoelasticity in clinical and research settings. In summary, the described protocol could be used to explore the effects of mucoactive drugs (e.g., rhDNase, N-acetyl cysteine) onsite to adapt treatment on a case-by-case basis, or in preclinical studies of novel compounds.

The viscoelastic properties of mucus play a critical role in mucociliary clearance. However, traditional mucus rheological techniques require complex and time-consuming approaches. This study provides a detailed protocol for the use of a benchtop rheometer that can rapidly and reliably perform viscoelastic measurements.

正交叠加流变学校准程序

摘要

探索更多视频

此视频中的章节

与CO平衡的原油流变学测量

介电RheoSANS - 阻抗，流变性和复杂流体的小角中子散射的同时拷问

挑战流变特性高度集中悬架 - 为例进行丝网印刷银浆

细胞外基质刚性三维肿瘤模型的纵向测量用粒子跟踪Microrheology

微流体和 Microrheology 相结合测定软物质在重复相变过程中的流变特性

软材料大振幅振荡剪切响应的研究

银鲤鱼中吉尔 · 拉克 · 穆库斯的宏观流变特征，低语种米希里斯 · 莫利特里克斯

用于动态界面共聚焦显微镜可视化的微量天体测量仪

表征使用原子力显微镜，冲击压痕和流变测定脑组织的多尺度力学性能

使用台式流变仪快速表征气道粘液的粘弹性

正交叠加流变学校准程序

摘要

探索更多视频

此视频中的章节

与CO平衡的原油流变学测量

介电RheoSANS - 阻抗，流变性和复杂流体的小角中子散射的同时拷问

挑战流变特性高度集中悬架 - 为例进行丝网印刷银浆

细胞外基质刚性三维肿瘤模型的纵向测量用粒子跟踪Microrheology

微流体和 Microrheology 相结合测定软物质在重复相变过程中的流变特性

软材料大振幅振荡剪切响应的研究

银鲤鱼中吉尔 · 拉克 · 穆库斯的宏观流变特征， 低语种米希里斯 · 莫利特里克斯

用于动态界面共聚焦显微镜可视化的微量天体测量仪

表征使用原子力显微镜，冲击压痕和流变测定脑组织的多尺度力学性能

使用台式流变仪快速表征气道粘液的粘弹性

银鲤鱼中吉尔 · 拉克 · 穆库斯的宏观流变特征，低语种米希里斯 · 莫利特里克斯