Name: blast quantification using hopkinson pressure bars
Uploaded: 2016-07-05T14:00:00.000+00:00
Duration: 9 min 41 s
Description: Watch this Scientific Journal Video about Blast Quantification Using Hopkinson Pressure Bars at JoVE.com

The authors wish to thank the Defence Science and Technology Laboratory for funding the published work.

1.刚反力架<ol><li>确定经缩放的距离在该测试将采取使用公式1，其中，R是从炸药的中心的距离的地方，并且W是质量表示为TNT的等效质量的电荷。 Z = R / W 1/3（1） </li><li>计算近似的最大冲击这一安排将通过数值模拟产生（见附录A）或诸如ConWep 3特定的工具。 注意:使用ConWep 3的仅适用于自由空气鼓风，是否需要从埋电荷产生的压力的估计，需要更先进的数值模拟。 </li><li>从造型检查估计负载不会产生面内的超过0.5毫米的目标板的位移。 </li><li>增加了10倍计算出的负载占在建模误差，并为未来的TES增加灵活性婷。 </li><li>设计一个刚性的反应框架能够抵御16计算的最大负荷。工程部门，执行内部这些计算;否则寻求结构工程师的服务。 <ol><li>促使刚性反应框架，承揽专业承包商制造和安装帧结构工程师的设计。 </li></ol></li><li>采购目标板，承揽专家钢制造商。 注意，该板将需要被安装在负载细胞（如果使用的话），并且用于HPBs（第3节中设计的）的孔将需要通过板安装之前钻出。 </li></ol><img alt="图1" src="/files/ftp_upload/53412/53412fig1.jpg" /> 图1.原理测试框架（ 一 ）统筹安排，（B）目标板的计划，（C）目标板的特写图。 ŧ让他们坐下来与目标板的表面齐平，他霍普金森杆从酒吧组装接收器挂起。这样就可以记录作用于目标板充分体现压力。 <a href="https://www.jove.com/files/ftp_upload/53412/53412fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 2.负载单元设计<ol><li>采购或制造称重传感器（如果使用）。这些可以是关闭的，现成的通用（压缩/张力）应变计罐模型或内置在内部使用焊接到安装在惠斯登电桥形成固定应变仪板厚壁软钢管材的截面， 如图2。 </li><li>如果负载细胞已在内部被制作，并将它们发送到校准外部承包商。 </li></ol><img alt="图2" src="/files/ftp_upload/53412/53412fig2.jpg" /> 图2.图在内部制造的称重传感器。（A）侧视图，（B）结束高程 。深灰色的钢瓶是厚壁钢管装下这株。该菌株用作装载过程中没有旋转经历一个应变仪记录下来。来自称重传感器应变可以与回施加的应力的校准。 <a href="https://www.jove.com/files/ftp_upload/53412/53412fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 3. Hopkinson压杆设计<ol><li>确定记录的持续时间， <img alt="公式9" src="/files/ftp_upload/53412/53412eq9.jpg" /> ，捕捉从爆炸的满载要求。所需的最低持续时间是在数值模型（1.2节）的压力返回到零，在初始压力​​尖峰之后的时间。在这里，使用1.2毫秒。 </li><li>德西德上选择用于HPBs的材料。这会影响弹性波的速度， <img alt="10式" src="/files/ftp_upload/53412/53412eq10.jpg" /> ，其中由下式给出的条<img alt="11式" src="/files/ftp_upload/53412/53412eq11.jpg" />哪里<img alt="12式" src="/files/ftp_upload/53412/53412eq12.jpg" />是杨氏模量和<img alt="13式" src="/files/ftp_upload/53412/53412eq13.jpg" />是密度。用于测量高压电击，用硬材料，如钢;在这里，如果一个较弱冲击的预期，使用较少的硬材料如镁合金或甚至尼龙。 </li><li>选择在HPB的立场是应变计将被定位，是尽可能接近到HPB的装载面对，以尽量减少分散。在靶板的当前的建立的厚度和以适应杆就位所需的操作性意味着压力表只能安装从装入面250毫米。 </li><li>计算HP使用要求B长度<img alt="14式" src="/files/ftp_upload/53412/53412eq14.jpg" /> ，其中<img alt="15式" src="/files/ftp_upload/53412/53412eq15.jpg" />是从HPB的装载面的应变仪的距离和<img alt="16式" src="/files/ftp_upload/53412/53412eq16.jpg" /> （3.25米）。 </li><li>确定所需HPB半径有足够的带宽使用捕获事件: <img alt="17式" src="/files/ftp_upload/53412/53412eq17.jpg" />千赫，其中<img alt="18式" src="/files/ftp_upload/53412/53412eq18.jpg" />是在毫米22,23（5毫米）的HPB半径。 </li><li>决定捕捉的压力在整个板的分布所需要的空间分辨率。这通常是尽可能接近，同时保持目标板的结构完整性。在目前的工作中，使用25毫米。 </li><li>在目标板装入HPBs钻孔（这可以是制造过程的一部分）。紧密配合，需要无覆盖旦是HPBs与板接触。这里，使用容差为0.5mm，在十字形状（ 图1b）被钻17的孔。 </li><li>促使HPBs（17），并确保有螺纹，以允许悬浮液在杆组件接收机（ 图3A）的远端。 </li></ol> 4.实验装置及数据采集注意:对于该反应框架，靶板， ​​测压元件和HPBs设计和制造，组装可以开始， 如图1，而在协议部分1而设计的。 <ol><li>安装半导体应变片HPBs（ 图3B）和称重传感器使用瞬干胶，小心翼翼地确保通过所有的电缆接地的连续性。用于HPBs惠斯登电桥的一个例子示于图3C。 <ol><li>确认所有接地电缆连接，以确保地球上的连续性。良好接地测试仪将提高信号质量明显。 </li></ol></li><li>确保布线是足够长，以确保示波器是在鼓风自由区域（屏蔽布线应当使用具有足够的信号带宽）可定位。 </li><li>适合目标板到刚性反应帧，使用可选的称重传感器（如果存在）（ 图1C）。 </li><li>杭HBPS从酒吧组装接收器，通过加载端穿过靶板正确的孔径。从旋到HPB的螺纹远端的螺母自由悬挂的HPBs。 </li><li>确保酒吧用酒精水准仪（相应地调整接收器）是垂直的。 </li><li>检查HPBs的面是与目标板水平，相应地调整螺母。 </li><li>设置在调理电路（ 图3C）的可变电阻器的微调，以保持示波器的测试期间的范围内的电压。通过试验做到这一点，错误旨在设定失去平衡各通道上的数字读出作为看到的放大器框为零。 </li><li>连接扩增仪输出到合适的数字示波器。配置为具有取样频率（1.56兆赫），记录持续时间（28.7毫秒）为3.3毫秒的预触发时间。 <ol><li>设置在记录时，在断裂线通道上的电压（其本身有线到示波器）超过一个"超出窗口"来触发。对于每个连接的压力表（总共22，17 HPBs，4个称重传感器和休息线）和时间记录电压。 </li></ol></li></ol><img alt="图3" src="/files/ftp_upload/53412/53412fig3.jpg" /> 图3.（A）图装到目标板，通过HPB（B）部分在表安装位置，（C）例如惠斯通电桥电路的HPB的。两个应变计在惠斯通电桥，使得使用和Hopkinson杆弯曲为cancelled出来。 <a href="https://www.jove.com/files/ftp_upload/53412/53412fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 5.准备爆炸<ol><li>决定的炸药量和对峙在测试中所使用（为75毫米100克PE4）。 </li><li>决定收费是否在自由空气或其他介质（土壤，水等 ）内被引爆。对于自由的空气测试一个球形形状主管通常利用而埋收费标准是3:1蹲缸24,25。 </li><li>对于自由空气测试: <ol><li>暂停在正确的对峙（75毫米）的目标板下方的电荷。用细木条或通过将负责对聚乙烯的薄片实现这一目标。 </li><li>放置电荷同轴与测量阵列，以确保有效的读数。 </li><li>对于自由空气测试使用的电雷管，雷管放置半进入从基座上的电荷。射击时的范围内已经取得安全之前，在最后时刻做到这一点。 </li></ol></li><li>对于埋地测试: <ol><li>制造为介质的合适的容器中。对于土壤，目前测试使用1/4比例的容器23。 </li><li>作出决定要利用的土壤类型和岩土条件:水分含量和土壤的干密度，见参考文献15更多细节。 </li><li>决定埋藏深度在测试中使用。这通常为100毫米的全尺寸试验，因为目前的测试在四分之一比例完成。这意味着25毫米的埋藏深度。 </li><li>混合土壤彻底使用适当大小的建筑混合器达到目标水分含量。为砂所需的混合时间是10分钟。 <ol><li>通过除去少量检查混合物的水分含量并称重，以计算总质量， <img alt="19式" src="/files/ftp_upload/53412/53412eq19.jpg" /> 。干除去的土壤，并重新称重来计算的水的质量， <img alt="20式" src="/files/ftp_upload/53412/53412eq20.jpg" /> 。岩土水分含量在重量的水分含量来规定， <img alt="21式" src="/files/ftp_upload/53412/53412eq21.jpg" /> 。 </li><li>如果含水量内容差继续，否则重新混合的土壤。的±0.05-0.1％的容差已在当前的工作已经实现。 </li></ol></li><li>称量空容器的土壤和计算体积，使土壤密度计算一次全（步骤5.4.7）。 </li><li>压缩在层中的土壤，足够薄，以保证在目标密度，确保土壤进入容器的质量是已知的。对于莱顿巴扎德沙15这是在两层完成。 </li><li>一旦容器是满的，检查土壤的密度范围内的公差（±0.2％）。在莱顿巴扎德砂所有测试目标干密度为1.6毫克/米3。计算干密度，使用<img alt="式（22）" src="/files/ftp_upload/53412/53412eq22.jpg" /> ，其中ρd是干密度，M是土壤加入到容器中的总质量，V是土壤容器的容积和w是水分含量。 </li><li>挖掘一个小孔≈50毫米，以允许电荷在正确的埋藏深度（25毫米）被放置在顶表面。 </li><li>放置的非电雷管到电荷的基础上，并且挖掘一个合适的信道，以在容器的侧面，以确保一旦土壤被替换的容器的顶面是不间断的。 </li><li>将装药和雷管到挖好的洞，检查埋藏深度是正确的。回填土出土材料的孔中。 </li></ol></li></ol> 6.点火顺序注意:有一个与协议第5条的重叠少量由于NAT测试的URE。该点火顺序应着眼于最大限度地降低风险，只能由经过适当培训的工作人员进行。 <ol><li>对于自由空气测试: <ol><li>安排在正确的对峙（75毫米）目标板下方的免费支持。 </li><li>关闭范围。部署哨兵保证范围为烧制过程清晰。 </li><li>将负责向支持同轴的仪器。附加断丝到雷管，并将雷管中的电荷。 </li></ol></li><li>对于埋地测试: <ol><li>放置土壤容器，使得电荷被置于同轴到HPB阵列。 </li><li>关闭范围。部署哨兵保证范围为烧制过程清晰。 </li><li>连接线突破，以确保它是围绕充电外围（这使引爆埋费更可重复的时间）包裹。 </li></ol></li><li>移动到发射点，并确认仪器正在运行。 </li><li>供电破线。请与哨兵它是安全的烧制进行。 </li><li>启动炸药。使试验区的安全。 </li><li>下载并备份数据。 </li><li>重新打开测试范围。 </li></ol> 7.一种用于一维HPB阵列的数值内插<ol><li>从原始数据文件中的数据导入到Matlab。 </li><li>使每一杆的峰值压力到达的同时使用等式2（ 图4B）的中心杆的峰值压力在径向方向上的时间偏移的所有数据。 <img alt="23式" src="/files/ftp_upload/53412/53412eq23.jpg" /> （2） </li><li>插在从图4B任何径向距离上的压力。 </li><li>画出到达时间（ <img alt="24式" src="/files/ftp_upload/53412/53412eq24.jpg" /> ）用于对准的峰值压力和适合通过数据（ 图4C）的立方方程式。 </li><li>内插数据的时间偏移，以适应到达时间，属婷连续冲击前（ 图4D）。 </li><li>重复每个单独的测试数据。 </li></ol><img alt="图4" src="/files/ftp_upload/53412/53412fig4.jpg" /> 图4.插值序列一维数组HPB（A）原始数据，（B），时移数据，（C）震前到达时间，和（D）最终的插值压时间数据16。压力时间历程的离散性可以清楚地在（A）和有作为峰值压力之间没有连续性在每五个轨距位置看到。当由峰值压力如在（B）的压力在任何径向距离内插（假定相同的到达时间）对准是可能的。通过记录对齐峰值压力震荡前沿的到达时间所需的时间偏移可被计算为的sh（C）中自己的。这就使得（B）和（C）给予所看到的（D）的最终插值的压力。时间要计算的到达时间和压力时程任何径向距离是从压力插<a href="https://www.jove.com/files/ftp_upload/53412/53412fig4large.jpg" target="_blank">请点击这里查看大图版本这个数字。</a> 8.一种用于二维HPB阵列的数值内插注意:用于运行在Matlab插值的代码已经与将在本节被称为一个示例结果文件一起提供。 <ol><li>从原始数据文件中的数据导入到Matlab。对于本例的测试数据，对test_data.mat双击文件，然后单击"完成"在导入向导。 </li><li>打开interpolation2d.m MATLAB脚本。 </li><li>定义规则的网格超过该插补通过改变网格运行。确保这是相同的分辨率在任何未来的数值模拟26,27的网格。这是在&#39;网格％细节"代码段设置。 </li><li>运行interpolation2d.m MATLAB脚本。请注意以下步骤中的代码被实现在这里列出了清晰度。 <ol><li>通过时移所有HPB压力痕迹<img alt="24式" src="/files/ftp_upload/53412/53412eq24.jpg" /> （式2）。原始数据示出了用于<img alt="25式" src="/files/ftp_upload/53412/53412eq25.jpg" />毫米图5B，使用相同的数据时移图5C。 注意:时移被要求允许插值例程成功定位的休克前在任何给定的时间。这主要涉及对齐数据对于每个放射状阵列，这样所有的最大压力对齐。 </li><li>计算半径， <img alt="26式" src="/files/ftp_upload/53412/53412eq26.jpg" />和昂<html>乐， <img alt="27式" src="/files/ftp_upload/53412/53412eq27.jpg" />用于对电网的兴趣的给定点， 如图5A所示。 </li><li>应用一维内插最靠近所述兴趣点两个HPB阵列为当前半径<img alt="26式" src="/files/ftp_upload/53412/53412eq26.jpg" /> （对于<img alt="28式" src="/files/ftp_upload/53412/53412eq28.jpg" />内插将使用<img alt="29式" src="/files/ftp_upload/53412/53412eq29.jpg" />和<img alt="30式" src="/files/ftp_upload/53412/53412eq30.jpg" />数组）。 </li><li>基于该2压力之间线性插入<img alt="31式" src="/files/ftp_upload/53412/53412eq31.jpg" /> （同样的<img alt="28式" src="/files/ftp_upload/53412/53412eq28.jpg" />加权将是50％ <img alt="29式" src="/files/ftp_upload/53412/53412eq29.jpg" />和的50％的<html> 12eq30.jpg"/&gt;阵列计算的压力）。 </li><li>由网格间距（区）内插的压力，得到负载乘以计算瞬时负载。 </li><li>由采样的时间步长乘以负载获得的瞬时脉冲。 </li><li>重复所有地点和时间（求和瞬间冲动给总冲）。 </li><li>时间偏移中的压力的时间记录为基于三次插值的冲击到达时间（ 图5D）的每个位置。 </li></ol></li></ol><img alt="图5" src="/files/ftp_upload/53412/53412fig5.jpg" /> 图5.插值序列二维数组HPB。用（A）登录约定，（B）的原始数据<img alt="35式" src="/files/ftp_upload/53412/53412eq35.jpg" />毫米，（C）的时移数据412 / 53412eq36.jpg"/&gt;毫米，并为每个径向方向16（D）的到达时间，对于酒吧2D阵列在任何点处的压力的时间历史取决于径向距离和哪个象限的兴趣点位于如果鼓风是完全对称的，然后在（B）中的压力将形成的垂直线，如图（C）中，在（B）中可以看出，冲击前是在达到50 mm的位置<img alt="30式" src="/files/ftp_upload/53412/53412eq30.jpg" />轴第一。 <a href="https://www.jove.com/files/ftp_upload/53412/53412fig5large.jpg" target="_blank">请点击此处查看该图的放大版本。</a>

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Impact Eng. 37 (7), 865-877 (2010).</li><li>Pickering, E. G., Chung Kim Yuen, S., Nurick, G. N., Haw, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+response+of+quadrangular+plates+to+buried+charges.">The response of quadrangular plates to buried charges.</a> Int. J. Impact Eng. 49, 103-114 (2012).</li><li>Bergeron, D. M., Trembley, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Canadian+research+to+characterize+mine+blast+output.">Canadian research to characterize mine blast output.</a> , (2000).</li><li>Hlady, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+soil+parameters+on+landmine+blast.">Effect of soil parameters on landmine blast.</a> , (2004).</li><li>Fourney, W. L., Leiste, U., Bonenberger, R., Goodings, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanism+of+loading+on+plates+due+to+explosive+detonation.">Mechanism of loading on plates due to explosive detonation.</a> Int. J. on Blasting and Fragmentation. 9 (4), 205-217 (2005).</li><li>Anderson, C. E., Behner, T., Weiss, C. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mine+blast+loading+experiments.">Mine blast loading experiments.</a> Int. J. Impact Eng. 38 (8-9), 697-706 (2011).</li><li>Fox, D. M., 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=The+response+of+small+scale+rigid+targets+to+shallow+buried+explosive+detonations.">The response of small scale rigid targets to shallow buried explosive detonations.</a> Int. J. Impact Eng. 38 (11), 882-891 (2011).</li><li>Ehrgott, J. Q., Rhett, R. G., Akers, S. A., Rickman, D. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+fabrication+of+an+impulse+measurement+device+to+quantify+the+blast+environment+from+a+near-surface+detonation+in+soil.">Design and fabrication of an impulse measurement device to quantify the blast environment from a near-surface detonation in soil.</a> Experimental Techniques. 35 (3), 51-62 (2011).</li><li>Pope, D. J., Tyas, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+hydrocode+modelling+techniques+to+predict+loading+parameters+from+free+air+hemispherical+explosive+charges.">Use of hydrocode modelling techniques to predict loading parameters from free air hemispherical explosive charges.</a> , (2002).</li><li>Clarke, S. D., 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=Repeatability+of+buried+charge+testing.">Repeatability of buried charge testing.</a> , (2014).</li><li>Clarke, S. D., 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+large+scale+experimental+approach+to+the+measurement+of+spatially+and+temporally+localised+loading+from+the+detonation+of+shallow-buried+explosives.">A large scale experimental approach to the measurement of spatially and temporally localised loading from the detonation of shallow-buried explosives.</a> Meas Sci Technol. 26, 015001 (2015).</li><li>Hopkinson, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Method+of+Measuring+the+Pressure+Produced+in+the+Detonation+of+High+Explosives+or+by+the+Impact+of+Bullets.">A Method of Measuring the Pressure Produced in the Detonation of High Explosives or by the Impact of Bullets.</a> Philos. Trans. R. Soc. (London) A. 213, 437-456 (1914).</li><li>Rigby, S. E., Tyas, A., Fay, S. D., Clarke, S. D., Warren, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validation+of+semi-empirical+blast+pressure+predictions+for+far+field+explosions+-+is+there+inherent+variability+in+blast+wave+parameters?.">Validation of semi-empirical blast pressure predictions for far field explosions - is there inherent variability in blast wave parameters?.</a> , (2014).</li><li>Rigby, S. E., Tyas, A., Bennett, T., Clarke, S. D., Fay, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+negative+phase+of+the+blast+load.">The negative phase of the blast load.</a> Int. J. of Protective Structures. 5 (1), 1-20 (2014).</li><li>Rigby, S. E., Fay, S. D., Tyas, A., Warren, J. A., Clarke, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Angle+of+incidence+effects+on+far-field+positive+and+negative+phase+blast+parameters.">Angle of incidence effects on far-field positive and negative phase blast parameters.</a> Int. J. of Protective Structures. 6 (1), 23-42 (2015).</li><li>Tyas, A., Warren, J., Bennett, T., Fay, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prediction+of+clearing+effects+in+far-field+blast+loading+of+finite+targets.">Prediction of clearing effects in far-field blast loading of finite targets.</a> Shock Waves. 21 (2), 111-119 (2011).</li><li>Tyas, A., Watson, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+study+of+the+effect+of+spatial+variation+of+load+in+the+pressure+bar.">A study of the effect of spatial variation of load in the pressure bar.</a> Meas Sci Technol. 11 (11), 1539-1551 (2000).</li><li>Tyas, A., Watson, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+investigation+of+frequency+domain+dispersion+correction+of+pressure+bar+signals.">An investigation of frequency domain dispersion correction of pressure bar signals.</a> Int. J. Impact Eng. 25 (1), 87-101 (2001).</li><li>NATO Standardisation Agency. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Procedures+for+evaluating+the+protection+level+of+logistic+and+light+armoured+vehicles.">Procedures for evaluating the protection level of logistic and light armoured vehicles.</a> Allied Engineering Publication (AEP) 55. 2, (2011).</li><li>Elgy, I. D., 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> UK ministry of defence technical authority instructions for testing the protection level of vehicles against buried blast mines. , (2014).</li><li>Clarke, S. 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O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> LS-DYNA theory manual. , (2006).</li><li>Fay, S. D., 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=Capturing+the+spatial+and+temporal+variations+in+impulse+from+shallow+buried+charges.">Capturing the spatial and temporal variations in impulse from shallow buried charges.</a> , (2013).</li><li>Fay, S. D., 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=Measuring+the+spatial+and+temporal+pressure+variation+from+buried+charges.">Measuring the spatial and temporal pressure variation from buried charges.</a> , (2014).</li></ol>

The authors have nothing to disclose.

使用提交上面概述的协议已经表明，有可能从炸药得到高度变负载的高保真测量，使用的霍普金森压力棒的阵列。使用插值例程概述的离散压力 - 时间历史记录可以转化成一个连续的冲击前它是直接使用如在数值模拟或作为这种模型的输出验证数据的加载功能。 当使用掩埋费用于制备在协议部分5中概述的土壤容器中的方法必须进行检查，以确保有足够的压实能量被提供以达?...

表征炸药输出有很多好处，军事（抵御当前冲突地区埋简易爆炸装置）和民用（设计结构部件）。近来这个话题已经得到相当的重视。多收集的知识已经针对从电荷输出的量化，以便更有效地保护结构的设计。这里的主要问题在于，如果所取得的测量是高保真的不那么在这些炸药事件负荷转移的机制尚不清楚。这反过来又导致了验证数值模式依赖于这些测量结果进行验证的问题。 近场的术语是用来描述与缩放的距离，Z小于〜1米/公斤1/3，其中Z = R / W 1/3，R是从炸药的中心的距离，而W爆炸在电荷质量表示作为TNT的等效质量。在这种状态的负载量为典型特征是非常高的幅度，高空间和时间上的非均匀的负荷。强大的仪器，因此被要求测量与近场加载相关的极端压力。在缩放距离ž&lt;0.4米/ kg的1/3，爆破参数的直接测量要么不存在或很少1和此范围内的半经验预测的数据几乎完全基于参数研究。这包括使用由Kingery和Bulmash 2，这是笔者的预期范围之外给出的半经验预测。虽然基于这些预测3,4工具允许装载的优秀一阶估计他们并不完全捕捉近场事件，这都是当前研究的重点的机制。 近场爆破的测量有近来集中量化OUTP从葬费UT斯达康。所采用的方法，从评估造成结构目标5-7全球直接冲击测量8-13变形而变化。这些方法提供了保护系统设计验证有价值的信息，但不能够完全调查负荷转移的机制。测试可以在两个实验室天平（1/10满刻度）进行，或在附近的满刻度（&gt; 1/4），与实际的理由，例如控制埋藏深度或确保休克前的没有固有形状是由所生成的使用雷管，而不是裸露的费用14。埋电荷的土壤条件需要进行高度控制，以保证在测试15的可重复性。 独立的电荷是否被放置在自由空气或埋设，在测量产生爆炸的最根本的问题是确保测量由仪器deplo制成的有效性YED。在设计的测试装置16固定的&#39;刚性&#39;的目标板是用来屏蔽霍普金森杆17（HPBs），而在同一时间确保杆的末端，只能记录充分体现压力。笔者以前曾表明反射压力的该测量从一个硬指标更准确，比事件重复，或"自由场"三围18-20。该板的几 ​​何形状是这样的，通过围绕目标边缘21清零或流动而产生的任何压力释放可以忽略不计。这个新的测试装置已在1/4比例被构造。在以上的埋藏条件和炸药这种规模紧密控制可以确保，与按比例缩小至78克5公斤满刻度充电的大小，在25毫米的埋藏深度。

<table><tbody><tr><td>Load Cell</td><td>RDP</td><td>RSL0960</td><td>This is only indicative, the exact load cell should be able to resolve the required loading</td></tr><tr><td>Steel target plate / HPBs</td><td>Garratts&amp;nbsp;</td><td></td><td>Fabricated to order</td></tr><tr><td>Strain gauge</td><td>Kyowa</td><td>KSP-2-120-E4</td><td>To use with steel HPBs</td></tr><tr><td>Cyanoacrylate</td><td>Kyowa</td><td>CC-33-A</td><td>Check with manufacturer depending on mar material to be used</td></tr><tr><td>Digital Oscilloscope</td><td>TiePie</td><td>HS4 16-bit Handyscopes&amp;nbsp;</td><td>6 used in parallel in current testing</td></tr><tr><td>Leighton Buzzard sand</td><td>Garside sands</td><td>Garside 14/25</td><td>Uniform silica sand&amp;nbsp;</td></tr></tbody></table>

blast quantification using hopkinson pressure bars

近场爆炸荷载的测量提供了一个问题的许多传感器类型，因为它们必须承受非常侵蚀性环境，并能够向上测量压力数百兆帕。在这方面，霍普金森压力棒的简单有，虽然Hopkinson杆的测定端可承受并暴露于恶劣的条件下，应变仪安装到杆可以一定距离被固定的一大优势。这允许利用防护罩用于保护所述应变计，但不与测量采集干扰。使用压力杆阵列的允许测量在离散已知点的压力 - 时间历史记录。本文还描述了用于在感兴趣的平面未仪表化的位置以得到压力 - 时间历史内插程序。目前，该技术已被用来测量在自由空气高能炸药装在各种土壤埋藏浅。

一个有效的刚性反应框架需要被提供。在目前的测试几百牛顿秒的总赋予的冲动需要以最小的变形予以抵制。用的硬质反应框架的图示于图1中给出。在每帧50毫米钢"受体"板已被铸入横梁的底部。虽然没有明确要求，这允许该负载细胞/靶板的容易固定，并提供额外的保护，以在混凝土梁的面。目前进行的接近的缩放距离已经0.15米/ kg的1/3。 <p class="j...

Watch this Scientific Journal Video about Blast Quantification Using Hopkinson Pressure Bars at JoVE.com

Blast Quantification Using Hopkinson Pressure Bars

This protocol details the use of Hopkinson pressure bars to measure reflected blast loading from near-field explosive events. It is capable of interpolating a pressure-time history at any point on a reflective boundary and as such can be used to fully characterize the spatial and temporal variations in loading produced.

高炉利用定量霍普金森杆

Near-field blast load measurement presents an issue to many sensor types as they must endure very aggressive environments and be able to measure pressures ...

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8.9K 次观看.  University of Sheffield. This protocol details the use of Hopkinson pressure bars to measure reflected blast loading from near-field explosive events. It is capable of interpolating a pressure-time history at any point on a reflective boundary and as such can be used to fully characterize the spatial and temporal variations in loading produced.

视频: Blast Quantification Using Hopkinson Pressure Bars

Impulsive Pressurization of Neuronal Cells for Traumatic Brain Injury Study

A novel impulsive cell pressurization experiment has been developed using a Kolsky bar device to investigate blast-induced traumatic brain injury (TBI). We demonstrate in this video article how blast TBI-relevant impulsive pressurization is applied to the neuronal cells in vitro. This is achieved by using well-controlled pressure pulse created by a specialized Kolsky bar device, with complete pressure history within the cell pressurization chamber recorded. Pressurized neuronal cells are inspected immediately after pressurization, or further incubated to examine the long-term effects of impulsive pressurization on neurite/axonal outgrowth, neuronal gene expression, apoptosis, etc. We observed that impulsive pressurization at about 2 MPa induces distinct neurite loss relative to unpressurized cells. Our technique provides a novel method to investigate the molecular/cellular mechanisms of blast TBI, via impulsive pressurization of brain cells at well-controlled pressure magnitude and duration.

A novel impulsive cell pressurization experiment has been developed using a Kolsky bar device to investigate the molecular/cellular mechanisms of blast-induced traumatic brain injury.

创伤性脑损伤研究神经细胞的脉冲增压

A novel impulsive cell pressurization experiment has been developed using a Kolsky bar device to investigate blast-induced traumatic brain injury (TBI). ...

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Research and Development of High-performance Explosives

Developmental testing of high explosives for military applications involves small-scale formulation, safety testing, and finally detonation performance tests to verify theoretical calculations. For newly developed formulations, the process begins with small-scale mixes, thermal testing, and impact and friction sensitivity. Only then do subsequent larger scale formulations proceed to detonation testing, which will be covered in this paper. Recent advances in characterization techniques have led to unparalleled precision in the characterization of early-time evolution of detonations. The new technique of Photonic Doppler Velocimetry (PDV) for the measurement of detonation pressure will be shared and compared with traditional fiber-optic detonation velocity and plate-dent calculation of detonation pressure. In particular, the role of aluminum in explosive formulations will be discussed. Recent developments led to the development of explosive formulations that result in reaction of aluminum very early in the detonation product expansion. This enhanced reaction leads to changes in the detonation velocity and pressure due to reaction of the aluminum with oxygen in the expanding gas products.

Developmental testing of high explosives for military applications involves small-scale formulation, safety testing, and finally detonation performance tests to verify theoretical calculations. This paper will share typical development tests associated with the measurement of detonation velocity and detonation pressure.

高性能炸药的研究与发展

Developmental testing of high explosives for military applications involves small-scale formulation, safety testing, and finally detonation performance ...

工程学

Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis

Nuclear reaction analysis (NRA) via the resonant 1H(15N,&#945;&#947;)12C reaction is a highly effective method of depth profiling that quantitatively and non-destructively reveals the hydrogen density distribution at surfaces, at interfaces, and in the volume of solid materials with high depth resolution. The technique applies a 15N ion beam of 6.385 MeV provided by an electrostatic accelerator and specifically detects the 1H isotope in depths up to about 2 &#956;m from the target surface. Surface H coverages are measured with a sensitivity in the order of ~1013 cm-2 (~1% of a typical atomic monolayer density) and H volume concentrations with a detection limit of ~1018 cm-3 (~100 at. ppm). The near-surface depth resolution is 2-5 nm for surface-normal 15N ion incidence onto the target and can be enhanced to values below 1 nm for very flat targets by adopting a surface-grazing incidence geometry. The method is versatile and readily applied to any high vacuum compatible homogeneous material with a smooth surface (no pores). Electrically conductive targets usually tolerate the ion beam irradiation with negligible degradation. Hydrogen quantitation and correct depth analysis require knowledge of the elementary composition (besides hydrogen) and mass density of the target material. Especially in combination with ultra-high vacuum methods for in-situ target preparation and characterization, 1H(15N,&#945;&#947;)12C NRA is ideally suited for hydrogen analysis at atomically controlled surfaces and nanostructured interfaces. We exemplarily demonstrate here the application of 15N NRA at the MALT Tandem accelerator facility of the University of Tokyo to (1) quantitatively measure the surface coverage and the bulk concentration of hydrogen in the near-surface region of a H2 exposed Pd(110) single crystal, and (2) to determine the depth location and layer density of hydrogen near the interfaces of thin SiO2 films on Si(100).

We illustrate the application of 1H(15N,&#945;&#947;)12C resonant nuclear reaction analysis (NRA) to quantitatively evaluate the density of hydrogen atoms on the surface, in the volume, and at an interfacial layer of solid materials. The near-surface hydrogen depth profiling of a Pd(110) single crystal and of SiO2/Si(100) stacks is described.

通过与核反应分析深度剖面的表面和界面层和颗粒材料氢含量的定量

Nuclear reaction analysis (NRA) via the resonant 1H(15N,&#945;&#947;)12C reaction is a highly effective method of depth profiling that quantitatively and ...

A Uniaxial Compression Experiment with CO2-Bearing Coal Using a Visualized and Constant-Volume Gas-Solid Coupling Test System

Injecting carbon dioxide (CO2) into a deep coal seam is of great significance for reducing the concentration of greenhouse gases in the atmosphere and increasing the recovery of coalbed methane. A visualized and constant-volume gas-solid coupling system is introduced here to investigate the influence of CO2 sorption on the physical and mechanical properties of coal. Being able to keep a constant volume and monitor the sample using a camera, this system offers the potential to improve instrument accuracy and analyze fracture evolution with a fractal geometry method. This paper provides all steps to perform a uniaxial compression experiment with a briquette sample in different CO2 pressures with the gas-solid coupling test system. A briquette, cold-pressed by raw coal and sodium humate cement, is loaded in high-pressure CO2, and its surface is monitored in real-time using a camera. However, the similarity between the briquette and the raw coal still needs improvement, and a flammable gas such as methane (CH4) cannot be injected for the test. The results show that CO2 sorption leads to peak strength and elastic modulus reduction of the briquette, and the fracture evolution of the briquette in a failure state indicates fractal characteristics. The strength, elastic modulus, and fractal dimension are all correlated with CO2 pressure but not with a linear correlation. The visualized and constant-volume gas-solid coupling test system can serve as a platform for experimental research about rock mechanics considering the multifield coupling effect.

A Uniaxial Compression Experiment with CO2-Bearing Coal Using a Visualized and Constant-Volume Gas-Solid Coupling Test System

This protocol demonstrates how to prepare a briquette sample and conduct a uniaxial compression experiment with a briquette in different CO2 pressures using a visualized and constant-volume gas-solid coupling test system. It also aims to investigate changes in terms of coal&#8217;s physical and mechanical properties induced by CO2 adsorption.

使用可视化和恒定体积气体-固体耦合测试系统使用 CO2轴承煤的单轴压缩实验

Injecting carbon dioxide (CO2) into a deep coal seam is of great significance for reducing the concentration of greenhouse gases in the atmosphere and ...

环境科学

A Coupled Experiment-finite Element Modeling Methodology for Assessing High Strain Rate Mechanical Response of Soft Biomaterials

This study offers a combined experimental and finite element (FE) simulation approach for examining the mechanical behavior of soft biomaterials (e.g. brain, liver, tendon, fat, etc.) when exposed to high strain rates. This study utilized a Split-Hopkinson Pressure Bar (SHPB) to generate strain rates of 100-1,500 sec-1. The SHPB employed a striker bar consisting of a viscoelastic material (polycarbonate). A sample of the biomaterial was obtained shortly postmortem and prepared for SHPB testing. The specimen was interposed between the incident and transmitted bars, and the pneumatic components of the SHPB were activated to drive the striker bar toward the incident bar. The resulting impact generated a compressive stress wave (i.e. incident wave) that traveled through the incident bar. When the compressive stress wave reached the end of the incident bar, a portion continued forward through the sample and transmitted bar (i.e. transmitted wave) while another portion reversed through the incident bar as a tensile wave (i.e. reflected wave). These waves were measured using strain gages mounted on the incident and transmitted bars. The true stress-strain behavior of the sample was determined from equations based on wave propagation and dynamic force equilibrium. The experimental stress-strain response was three dimensional in nature because the specimen bulged. As such, the hydrostatic stress (first invariant) was used to generate the stress-strain response. In order to extract the uniaxial (one-dimensional) mechanical response of the tissue, an iterative coupled optimization was performed using experimental results and Finite Element Analysis (FEA), which contained an Internal State Variable (ISV) material model used for the tissue. The ISV material model used in the FE simulations of the experimental setup was iteratively calibrated (i.e. optimized) to the experimental data such that the experiment and FEA strain gage values and first invariant of stresses were in good agreement.

The current study prescribes a coupled experiment-finite element simulation methodology to obtain the uniaxial dynamic mechanical response of soft biomaterials (brain, liver, tendon, fat, etc.). The multiaxial experimental results that arose because of specimen bulging obtained from Split-Hopkinson Pressure Bar testing were rendered to a uniaxial true stress-strain behavior when simulated through iterative optimization of the finite element analysis of the biomaterial.

一个耦合试验，有限元建模方法以评估生物材料软的高应变率力学响应

This study offers a combined experimental and finite element (FE) simulation approach for examining the mechanical behavior of soft biomaterials (e.g. ...

Conducting Elevated Temperature Normal and Combined Pressure-Shear Plate Impact Experiments Via a Breech-end Sabot Heater System

A novel approach for conducting normal and/or combined pressure-shear plate impact experiments at test temperatures up to 1000 &#176;C is presented. The method enables elevated temperature plate-impact experiments aimed towards probing dynamic behavior of materials under thermomechanical extremes, while mitigating several special experimental challenges faced while performing similar experiments using the conventional plate impact approach. Custom adaptations are made to the breech-end of a single-stage gas-gun at Case Western Reserve University; these adaptations include a precision-machined extension piece made from SAE 4340 steel, which is strategically designed to mate the existing gun-barrel while providing a high tolerance match to the bore and keyway. The extension piece contains a vertical cylindrical heater-well, which houses a heater assembly. A resistive coil heater-head, capable of reaching temperatures of up 1200 &#176;C, is attached to a vertical stem with axial/rotational degrees of freedoms; this enables thin metal specimens held at the front-end of a heat-resistant sabot to be heated uniformly across the diameter to the desired test temperatures. By heating the flyer plate (in this case, the sample) at the breech-end of the gun-barrel instead of at the target-end, several critical experimental challenges can be averted. These include: 1) severe changes in the alignment of the target plate during heating due to the thermal expansion of the several constituents of the target holder assembly; 2) challenges that arise due to the diagnostics elements, (i.e., polymer holographic gratings, and optical probes) being too close to the heated target assembly; 3) challenges that arise for target plates with an optical window, where crucial tolerances between the sample, bond layer, and window become increasingly difficult to maintain at high temperatures; 4) in the case of combined compression-shear plate impact experiments, the need for high-temperature resistant diffraction gratings for the measurement of transverse particle velocity at the free surface of the target; and 5) limitations imposed on the impact velocity necessary for unambiguous interpretation of the measured free surface velocity versus time profile due to thermal softening and possibly yielding of the bounding target plates.By utilizing the adaptations mentioned above, we present results from a series of reverse geometry normal plate impact experiments on commercial purity aluminum at a range of sample temperatures. These experiments show decreasing particle velocities in the impacted state, which are indicative of material softening (decrease in post-yield flow stress) with increasing sample temperatures.

Here, we present a detailed protocol of a new approach for conducting elevated temperature reverse normal plate impact, and combined pressure-and-shear plate impact. The approach involves the use of a breech-end resistive coil heater to heat a sample held at the front-end of a heat-resistant sabot to the desired temperature.

采用臀端穿甲弹加热系统进行高温常压联合压力-剪切板冲击试验

A novel approach for conducting normal and/or combined pressure-shear plate impact experiments at test temperatures up to 1000 &#176;C is presented. The ...

Use of Atomic Force Microscopy to Measure Mechanical Properties and Turgor Pressure of Plant Cells and Plant Tissues

We present here the use of atomic force microscopy to indent plant tissues and recover its mechanical properties. Using two different microscopes in indentation mode, we show how to measure an elastic modulus and use it to evaluate cell wall mechanical properties. In addition, we also explain how to evaluate turgor pressure. The main advantages of atomic force microscopy are that it is non-invasive, relatively rapid (5~20 min), and that virtually any type of living plant tissue that is superficially flat can be analyzed without the need for treatment. The resolution can be very good, depending on the tip size and on the number of measurements per unit area. One limitation of this method is that it only gives direct access to the superficial cell layer.

Here, we present atomic force microscopy (AFM), operated as a nano- and micro-indentation tool on cells and tissues. The instrument allows the simultaneous acquisition of 3D surface topography of the sample and its mechanical properties, including cell wall Young's modulus as well as turgor pressure.

利用原子力显微镜测量植物细胞和植物组织的机械特性和Turgor压力

We present here the use of atomic force microscopy to indent plant tissues and recover its mechanical properties. Using two different microscopes in ...

发育生物学

A Novel In Vitro Model of Blast Traumatic Brain Injury

Traumatic brain injury is a leading cause of death and disability in military and civilian populations. Blast traumatic brain injury results from the detonation of explosive devices, however, the mechanisms that underlie the brain damage resulting from blast overpressure exposure are not entirely understood and are believed to be unique to this type of brain injury. Preclinical models are crucial tools that contribute to better understand blast-induced brain injury. A novel in vitro blast TBI model was developed using an open-ended shock tube to simulate real-life open-field blast waves modelled by the Friedlander waveform. C57BL/6N mouse organotypic hippocampal slice cultures were exposed to single shock waves and the development of injury was characterized up to 72 h using propidium iodide, a well-established fluorescent marker of cell damage that only penetrates cells with compromised cellular membranes. Propidium iodide fluorescence was significantly higher in the slices exposed to a blast wave when compared with sham slices throughout the duration of the protocol. The brain tissue injury is very reproducible and proportional to the peak overpressure of the shock wave applied.

A Novel In Vitro Model of Blast Traumatic Brain Injury

This paper describes a novel model of primary blast traumatic brain injury. A compressed-air driven shock tube is used to expose in vitro mouse hippocampal slice cultures to a single shock wave. This is a simple and rapid protocol generating a reproducible brain tissue injury with a high throughput.

一种新的脑外伤体损伤模型

Traumatic brain injury is a leading cause of death and disability in military and civilian populations. Blast traumatic brain injury results from the ...

神经科学

Low-intensity Blast Wave Model for Preclinical Assessment of Closed-head Mild Traumatic Brain Injury in Rodents

Traumatic brain injury (TBI) is a large-scale public health problem. Mild TBI is the most prevalent form of neurotrauma and accounts for a large number of medical visits in the United States. There are currently no FDA-approved treatments available for TBI. The increased incidence of military-related, blast-induced TBI further accentuates the urgent need for effective TBI treatments. Therefore, new preclinical TBI animal models that recapitulate aspects of human blast-related TBI will greatly advance the research efforts into the neurobiological and pathophysiological processes underlying mild to moderate TBI as well as the development of novel therapeutic strategies for TBI.
Here we present a reliable, reproducible model for the investigation of the molecular, cellular, and behavioral effects of mild to moderate blast-induced TBI. We describe a step-by-step protocol for closed-head, blast-induced mild TBI in rodents using a bench-top setup consisting of a gas-driven shock tube equipped with piezoelectric pressure sensors to ensure consistent test conditions. The benefits of the setup that we have established are its relative low-cost, ease of installation, ease of use and high-throughput capacity. Further advantages of this non-invasive TBI model include the scalability of the blast peak overpressure and the generation of controlled reproducible outcomes. The reproducibility and relevance of this TBI model has been evaluated in a number of downstream applications, including neurobiological, neuropathological, neurophysiological and behavioral analyses, supporting the use of this model for the characterization of processes underlying the etiology of mild to moderate TBI.

We present here a protocol of a blast wave model for rodents to investigate neurobiological and pathophysiological effects of mild to moderate traumatic brain injury. We established a gas-driven, bench-top setup equipped with pressure sensors allowing for reliable and reproducible generation of blast-induced mild to moderate traumatic brain injury.

低强度冲击波模型用于啮齿动物闭头轻度创伤性脑损伤的临床前评估

Traumatic brain injury (TBI) is a large-scale public health problem. Mild TBI is the most prevalent form of neurotrauma and accounts for a large number of ...

Shocktube 方法模拟小鼠高度重复的低水平爆炸

Modeling Highly Repetitive Low-level Blast Exposure in Mice

Exposure to explosive blasts is a significant risk factor for brain trauma among exposed persons. Although the effects of large blasts on the brain are well understood, the effects of smaller blasts such as those that occur during military training are less understood. This small, low-level blast exposure also varies highly according to military occupation and training tempo, with some units experiencing few exposures over the course of several years whereas others experience hundreds within a few weeks. Animal models are an important tool in identifying both the injury mechanisms and long-term clinical health risks following low-level blast exposure. Models capable of recapitulating this wide range of exposures are necessary to inform acute and chronic injury outcomes across these disparate risk profiles.
Although outcomes following a few low-level blast exposures are easily modeled for mechanistic study, chronic exposures that occur over a career may be better modeled by blast injury paradigms with repeated exposures that occur frequently over weeks and months. Shown here are methods for modeling highly repetitive low-level blast exposure in mice. The procedures are based on established and widely used pneumatic shocktube models of open-field blast exposure that can be scaled to adjust the overpressure parameters and the number or interval of the exposures. These methods can then be used to either enable mechanistic investigations or recapitulate the routine blast exposures of clinical groups under study.

作者聚焦:破译小鼠低水平爆炸暴露的长期影响

Presented here are methods for producing repeated low-intensity blast exposures using mice.

对小鼠高度重复的低水平爆炸暴露进行建模

Exposure to explosive blasts is a significant risk factor for brain trauma among exposed persons. Although the effects of large blasts on the brain are ...