共查询到20条相似文献,搜索用时 234 毫秒
1.
20 0 1年 9月 2 2日 11时 4 5分左右 ,广西融安县举办的桂北三县第八届“宝庆杯”龙舟大赛赛事正酣时 ,1只广告氢气球突然在人群中爆炸 ,造成 16人脸部、手部灼伤 (其中 6名儿童 )。据介绍 ,事发前已发现悬在空中的气球泄气 ,5名工作人员赶到现场将坠下的气球重新用鼓风机充气 ,因漏洞太大 ,他们就蹲下来用透明胶进行补漏时 ,就炸开了广西融安一氢气球爆炸16人被灼伤$杭州杭氧科技公司标准化室@项红 相似文献
2.
3.
4.
土地利用遥感动态监测能够快速提取土地利用变化信息,更新土地利用现状图,对于土地资源合理利用、科学管理具有重要的意义。本文主要阐述了土地利用动态遥感监测的方法和过程。 相似文献
5.
6.
提出了一种利用空域采样实现相移干涉计量的新方法和实验演示装置。演示装置使用倾斜镜或阶梯镜作为相移器件,线阵CCD做为光学传感器。实验表明:此方法非常适用于测量快速变化的目标或动态过程,其测量精度与传统时域采样相移技术相当但具有更好的稳定性和更高的测量速度,而测量范围是离焦量的2倍。 相似文献
7.
《中国新技术新产品》2016,(14)
系留气球是一种利用内部浮升气体净浮力升空的飞行器,随着其应用越来越广泛,对结冰探测的要求也越来越高。本文通过对系留气球产品的简介、结冰危害、结冰探测需求等方面出发,提出了利用现有飞机用结冰信号器来解决系留气球结冰探测问题的方法,包括安装位置、结冰程度判断等。 相似文献
8.
9.
反应磁控溅射方法制备AlN薄膜是一种很普遍的方法,但采用该方法制备时,各个参数相互作用使过程复杂化.为了增强对该过程的理解,建立了反应溅射过程的动态模型.应用该模型分析了当氮流量增加或减少时,过程中的各个参数随时间变化的瞬态行为.计算出的溅射参数与实测值相符.模型清楚地表明,过程的初始状态对其动态行为有显著的影响. 相似文献
10.
随着5G时代的到来,地震过程能通过密集分布的摄像头实时记录并快速传输处理,以动态图像的形式更直观地呈现出来。如能从中快速准确的提取地震动参数等数据,将会是地震资料的宝库,弥补地震台站布置密度的不足。通过振动台模拟地震过程,结合图像识别和结构动力学分析方法,提出一种基于图像动态识别技术的地震动参数快速判别方法。通过不同摄像头高度、波形和振动频率下的计算和实测加速度曲线对比分析,多数加速度峰值误差在40%以内,证明该方法具有应用推广价值,能为将来地震动分析工作提供另一层面的解决途径。 相似文献
11.
12.
为研究输气管道音波法泄漏检测技术的基本原理和应用方法,对输气管道中泄漏音波的产生机理进行了研究。首先从理论上确定输气管道气动噪声的产生机理;其次将仿真模拟得到四极子声源和偶极子声源产生的泄漏音波进行分析并总结规律;再次将音波传感器测得泄漏音波与仿真模拟得到的泄漏音波进行对比验证;然后对比分析多工况条件下仿真模拟和实验方法得到的泄漏音波;最后通过分析仿真模拟中泄漏音波产生机理和实验中所用的音波传感器的工作机理总结输气管道音波法泄漏检测技术的基本原理。研究结果表明:输气管道泄漏音波产生的根本原因是气体泄漏时产生的湍流脉动导致的四极子声源和偶极子声源;实验中音波传感器测得的压力波动主要成分为声源产生的音波波动;仿真模拟和实验的方法可以研究输气管道泄漏音波的产生机理。 相似文献
13.
论证了大爆破对水工隧洞的作用与影响,该问题可近似按弹性平面应变问题处理分析,在此简化前提下,进行了动态光弹性模型实验研究。文中介绍了该研究的试验方法与技术特点;得出在爆炸荷载作用下全过程模型动态应力等色线条纹图,揭示与解说了隧洞的爆炸动态响应应力变化过程;求得模型隧洞拱顶最大拉应力条纹整级数N_(max)与隧洞直径D对隧洞至爆源距离R的比值(即D/R)之间的关系,根据试验资料与模拟相似关系,给出了爆炸条件下估算圆形隧洞最大爆炸拉应力的经验表达式,该式可供工程应用与理论分析参考。 相似文献
14.
15.
16.
17.
18.
19.
Zimerman B Arnold M Ulmer J Blümmel J Besser A Spatz JP Geiger B 《IEE proceedings. Nanobiotechnology》2004,151(2):62-66
Cell motility consists of repeating cycles of protrusion of a leading edge in the direction of migration, attachment of the advancing membrane to the matrix, and pulling of the trailing edge forward. In this dynamic process there is a major role for the cytoskeleton, which drives the protrusive events via polymerisation of actin in the lamellipodium, followed by actomyosin contractility. To study the transition of the actin cytoskeleton from a 'protrusive' to 'retractive' form, we have monitored the formation of focal adhesions and stress fibres during cell migration on a micro-patterned surface. This surface consisted of parallel arrays of 2 microm-wide, fibronectin-coated gold stripes, separated by non-adhesive (poly(ethylene glycol)-coated) glass areas with variable width, ranging from 4-12 microm. Monitoring the spreading of motile cells indicated that cell spreading was equally effective along and across the adhesive stripes, as long as the non-adhesive spaces between them did not exceed 6 microm. When the width of the PEG region was 8 microm or more, cells became highly polarised upon spreading, and failed to reach the neighboring adhesive stripes. It was also noted that as soon as the protruding lamella successfully crossed the PEG-coated area and reached an adhesive region, the organisation of actin in that area was transformed from a diffuse meshwork into a bundle, oriented perpendicularly to the stripes and anchored at its ends in focal adhesions. This transition depends on actomyosin-based contractility and is apparently triggered by the adhesion to the rigid fibronectin surface. 相似文献
20.
Khac An Dao D. Khang Dao T. Dai Nguyen A. Tuan Phan Hung Manh Do 《Journal of Materials Science: Materials in Electronics》2012,23(11):2065-2074
Using VLS method with the separated 220 nm thick Au catalyst circles/stripes configurations sputtered onto GaAs substrate surface, this paper investigated the effects of the Au droplets/clusters formation as well as the nanowires growth process inside and outside the Au circles/stripes configurations. The Au surface outward diffusion from the Au layer edge up to several tens of micrometers has strongly dominated. The effects of Au surface diffusion to formation of Au droplets/cluster and to the nanowires growth on GaAs semiconductor substrate in the region outside the Au layers have been shown. The mechanism of the droplets/clusters formation outside the Au layer could explained by the surface cluster diffusion, meanwhile the nanowires have grown simultaneously during the Au outward diffusion. The growth could explain by the diffusion of Ga and As atoms into the diffusing Au droplets/clusters via dissociative mechanism to form nanowire seeds inside for nanowires growth. The Au droplets/clusters formation and nanowires growth on GaAs substrate outside Au layer could be applied for making nanodevices blocks outside the Au layer. Unfortunately if this Au surface diffusion phenomenon is occurring on the GaAs semiconductor containing the Au stripes interconnections in micro/nanocircuits this could also cause the short-circuits phenomenon, even at thin Au layer. 相似文献