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1.
为实现对纳米气泡粒径的原位和实时测量,将可视化粒子追踪与图像动态光散射技术相结合,开发出一种新的测量方法.首先,基于可视化方法,利用暗场显微镜成像,得到纳米气泡的原位粒径分布.然后,采用图像动态光散射法,对纳米气泡制备过程进行实时粒径监测,并得到了样品池中纳米气泡在稳态下的纵向粒径分布.结果表明,与商用ZetaSizer纳米粒子测量仪相比,利用所提测量方法能够获得整个样品池中的纳米气泡粒径信息,实验数据更详细,结果更准确.因此,该测量方法是一种准确性较高、实时简单的测量技术,为准确测量纳米气泡和纳米粒子的粒径分布提供了一种新手段.  相似文献   

2.
设计了一款快速高精度的甲醛自动测量仪.测量仪通过电化学甲醛传感器获取质量浓度信息,利用STM32单片机进行数据处理、储存.通过OLED模块显示质量浓度信息,另外开发了基于Android平台的监控软件系统,可实时显示当前质量浓度信息及历史数据.对该仪器的测量精度进行了测试,并与化学试剂检测结果进行精度对比分析,以验证该系统测量的准确性.在此基础上进行了两组封闭环境下甲醛质量浓度变化检测实验,结果表明,该甲醛自动监测仪具有操作界面简洁、精准度高、反应时间快等优点,能够远程检测甲醛质量浓度信息,具有一定的使用价值.  相似文献   

3.
本文综合前向小角光散理论及消光原理,提出一种测量粉尘平均粒径及粉尘浓度的光学方法.该方法测量透过粉尘的散射光在前向两个空间立体角内的光强及出射光强,可以方便地计算出粉尘的平均粒径及粉尘浓度的大小.实验结果表明该方法可作为一种在线的测尘方法.  相似文献   

4.
微气泡激光散射特性研究   总被引:4,自引:0,他引:4  
根据Mie散射理论研究了在水介质中微空气泡的光散射特性,给出了相应的散射强度分布、散射光的偏振度与散射角的关系,以及前向散射光强与气泡半径的关系.发现在一定波长下,前向散射光强与气泡半径呈线性关系,为空气泡的测量提供了理论模型.  相似文献   

5.
选煤厂产尘环节粉尘颗粒扩散方程的建立   总被引:1,自引:0,他引:1  
由风力扬起的粉尘是由不同粒径所组成的颗粒群,能否用数值方法再现出不同粒径的颗粒群的运动轨迹是预测含尘质量分数的前提和关键。从研究粉尘粒子在空间中的受力情况及在这些力作用下的运动状态,通过研究粉尘在紊流气流中的扩散规律,得出粉尘颗粒的运动轨迹,为最后达到粉尘控制奠定基础。  相似文献   

6.
交通信号灯的颜色可不是随意选用的哟,这其中大有学问呢!我们知道,空气中除了氮气、氧气等各种气体分子外,还悬浮着许多灰尘小颗粒,所以光在空气中传播时会产生散射现象.散射与光的波长有关,波长越短,散射作用越强.在可见光中,红光的波长最长,空气对它  相似文献   

7.
张彦斌 《教育技术导刊》2009,19(11):146-149
随着光散射法测量PM2.5颗粒物浓度技术的发展,该技术成为测量大气PM2.5浓度的主要手段之一。散射激光雷达接收到的信号为回波信号图,通过建立回波信号图灰度值与PM2.5浓度的关系模型,实现对颗粒物浓度的测量。该技术需要对回波信号图进行预处理并提取散射信号,为了实现一种高性能、可实时测量的回波信号图预处理系统,设计一款基于Delphi7语言的实时图像处理软件。该软件通过对内存分配双缓冲区域、设置采集频率以及图像裁剪等方法,提高图片的采集与处理速率。实验结果表明,该软件操作简单、运行稳定且可扩展性较强。  相似文献   

8.
设计了一种大气环境散射率测量装置,用于测量普通大气环境中粒子对激光散射率,用以反映测量环境对光束的散射程度,进而评估测量环境能否满足散射测量。该装置以稳功率激光器为光源,让光束穿过积分球空腔,使空腔内的粒子在空腔内发生散射,从而散射光都被积分球所收集,再使用光电倍增管测量积分球收集的散射光强,并采用相关检查方法进行信号处理,有效去除背景噪声。在实验室环境进行了测量,结果表明,测量精度最高可达0.1×10~(-6),装置误差达到±2%,实现了散射率的高精度测量。  相似文献   

9.
通过粉尘粒径与扬尘风速关系研究,得到通过增大矿尘粒径,增大其扬尘风速,从而减少矿尘飞扬的方法;通过粉尘间凝聚力的比较分析,得到粉尘的保湿能使液体桥联力起主导作用力,促使小颗粒积聚成大颗粒,减少矿井扬尘的结论。YCH抑尘剂的应用说明,它能使路面上松散细小粉尘湿润凝并,不仅使单个粉尘质量增大而且粉尘间作用力也增大,降低粉尘扬起。  相似文献   

10.
交通信号灯是维护交通秩序、保障交通安全和畅通的重要保障,因此交通信号灯的颜色可不是随意选用的,这其中大有学问呢! 我们知道,空气中除了氮气、氧气等各种气体外,还悬浮着许多灰尘小颗粒,所以光在空气中传播时会产生散射现象。散射与光的波长有关,波长越短,散射作用越强。在可见光  相似文献   

11.
汉字倒说     
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。  相似文献   

12.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

13.
一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/  相似文献   

14.
《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?  相似文献   

15.
钱生钱!     
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了  相似文献   

16.
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex.  相似文献   

17.
《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.  相似文献   

18.
王菲 《华章》2007,(12):273-273
Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.  相似文献   

19.
现在,我们可以没有面包,没有钱,没有房子,没有车子……但我们唯独不能丢失的是高尚的情操,笃定的信念,还有,满满的希望!  相似文献   

20.
Using virtual reality for interactive design gives a designer an intuitive vision of a design and allows the designer to achieve a viable, optimal solution in a timely manner. The article discusses the process of making the Virtual Reality System of the Humble Administrator's Garden. Translating building data to the Virtual Reality Modeling Language (VRML) is by far unsatisfactory. This creates a challenge for computer designers to do optimization to meet requirements. Five different approaches to optimize models have been presented in this paper. The other methods are to optimize VRML and to reduce the file size. This is done by keeping polygon counts to a minimum and by applying such techniques as object culling and level-ofdetail switching.  相似文献   

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