常州市衡正电子仪器有限公司是一家集软件开发、制造、销售、服务于一体的科技型现代化企业。
扫描手机二维码
扫描微信二维码
13861223798

新闻中心

NEWS CENTER

网站公告:测试信息来自互联网,若涉及侵权,请联系我们删除! 您当前所在位置:首页 > News > company news > 正文返回

Understand some of the knowledge of surface tension

更新时间:2017-04-20 10:28:04点击次数:1815次字号:T|T
As we all know, we can explain the nature of the liquid according to the mutual attraction between molecules. The attraction of this molecule is called molecular cohesion or van der Waals force. The surface tension, interfacial tension and similar phenome
What is surface tension?
As we all know, we can explain the nature of the liquid according to the mutual attraction between molecules. The attraction of this molecule is called molecular cohesion or van der Waals force. The surface tension, interfacial tension and similar phenomena are used to explain the basic physical phenomena of molecular cohesion.
Specifically, the force of the molecules constituting the liquid on the surface is not the same as that within the body. The forces in the body are symmetrical and balanced. While the molecules on the surface are attracted by the molecules in the body without counterbalance. That is to say, it is pulled into the body of the force. In other words, trying to narrow the surface area, so that this imbalance in the state tends to balance the state. The theory of thermodynamics is to minimize the surface energy of the system, which is called "surface tension", also known as the free energy per unit area (J / m2), that is, the formation or expansion of the unit area of the interface The minimum energy required. Its value is consistent with the surface tension (N / m). Due to the habit, the commonly used surface tension represents the surface free energy, which plays a vital role in the physical and chemical phenomena on the liquid surface. In daily life, morning dew on the lotus leaves, cups in the curved surface, etc. are surface tension phenomenon.
Several methods commonly used to measure surface / interfacial tension
First, the platinum plate method
When the sensation of the platinum plate immersed in the measured liquid, the platinum plate will be affected by the role of surface tension, the liquid surface tension will pull down the platinum plate as much as possible. When the liquid surface tension and other related force and balance force to achieve a balance, the sensing platinum plate will stop into the liquid inside the immersion. At this time, the balance sensor of the instrument measures the depth of immersion and converts it into the surface tension of the liquid.
In the specific test process, the platinum plate method of the test steps are: (1) the platinum plate gradually immersed in the liquid; (2) immersed in the liquid surface state, by the sensor sense of balance; (3) will be the balance value Converted to surface tension values and displayed.
Second, the platinum ring method
Also known as du Nouy Ring method, du Nouy ring method, ring method surface tension meter, de-ring surface tension meter. The principle is: (1) the platinum ring gently immersed in the liquid; (2) the platinum ring slowly up, that is, the relative decline in liquid surface, making the platinum ring below the formation of a liquid column, and eventually with Separation of platinum rings. The platinum ring method is to sensate a maximum value, and this highest value is formed in the platinum ring with the liquid sample that will depart from the time. Because this method is used very early, so the original surface tension meter are basically using this method, a lot of existing data is measured in this way.
1. The platinum ring hangs over the liquid surface and has been zeroed.
2. Platinum ring has just come into contact with the liquid surface, because the platinum ring at this time contact with the liquid surface that layer of film; At this point the display began to show the value. (The number is small or negative)
3. Platinum ring began to immerse into the liquid inside, because the role of surface tension shows the value began to become larger.
4. Platinum ring immersed in the liquid to stop at 5mm, this time the value is displayed on the liquid two platinum rings connected to the role of the surface tension. (The size of the value depends on the wire diameter)
5. Start slowly lowering the sample stage.
6. The value on the display is getting larger.
7. As the sample stage slows down, the platinum ring forms a column of liquid film over the liquid surface. The value shown at this point has reached the maximum.
8. The final platinum ring and liquid from the liquid film rupture, showing a reduced value.
(The above two test methods are the most commonly used method)
Third, the largest bubble method
Four, spin drop method
This method is suitable for measuring ultra-low interfacial tension, the range is generally below 10mN / m.
(编辑:HengZheng)
0 条评论
不想登录?直接点击发布即可作为游客留言。

新闻中心列表

公司新闻
行业资讯

新闻推荐

FA系列电子天平日常使用方法是...

FA系列电子天平按结构可分为上皿式和下皿式两种。称盘在支架上面为...

JA系列电子天平怎么用?

小颗粒物和液体在称量时一般都是需要使用容器,我们可先将空的容器放...

电子天平称重结果不稳定有哪些原...

通过拆解,可以看出电子天平是精密的机电仪表,比较娇气,操作规程要...

卤素水分测定仪测量不准确的原因...

卤素水份仪是一种新型快速的水分检测仪器。采用环形卤素灯加热,智能...

如何选购合适的电子天平?

选择电子天平应该从电子天平的绝对精度(分度值e)上去考虑是否符合称量...

电子天平校准的方法有几种?

电子天平在长时间未使用或第一次使用前都要进行校准,否则就会导致测...

FA系列电子天平使用方法

FA系列电子天平采用高精度电磁力平衡传感器。使得测量结果精确性更...

联系我们

地址:江苏省常州市钟楼区龙城大道2188号新闸科技园

联系人:查小姐
邮编:213000
电话:0519-83263587
传真:0519-83268313
网址:http://www.czhzyq.com/

联系我们
地址:常州市钟楼区龙城大道2188号新闸科技园10栋313
联系人:查小姐
电话:0519-83263587
传真:0519-83268313
网址:http://www.czhz17.com
关注衡正
Copyright © 2017 - 2024 All Rights Reserved 常州市衡正电子仪器有限公司 版权所有  苏ICP备17024635号 技术支持:冉冉科技 网站地图