The captive bubble method is a method for measuring contact angle between a liquid and a solid, by using drop shape analysis. In this method, a bubble of air is injected beneath a solid, the surface of which is located in the liquid, instead of placing a drop on the solid as in the case of the sessile drop technique. The method is particularly suitable for solids with high surface free energy on which liquids spread out. Hydrogels, such as soft contact lenses for example, are likewise inaccessible for the standard arrangement; the captive bubble method is also used in such cases. The captive bubble method is a scientific method for measuring the contact angle between a solid surface and liquid in a fluid. A contact angle is formed on a smooth, periodically heterogeneous solid surface. Above the solid surface, a liquid drop is submerged to the solid in a fluid. The measurement of contact angles usually contributes to the measurement of the surface energy of solids in the industry. Different from other methods of measuring the contact angle, such as the sessile drop method, the system utilized in the captive bubble method has the fluid bubble attached from below to the solid surface, in which both the liquid bubble and the solid interact with a fluid. (Wikipedia).
Hydraulic cylinder with fixed piston
Green cylinder with machine table reciprocates. Pressure fluid is conducted into cylinder via holes on fixed piston rod. The hoses can be stationary. In case using holes on the cylinder the hoses have to move with the cylinder. The arrows show flows of pressure fluid.
From playlist Mechanisms
This video will show how to make a vacuum pump, a device that can be used to suck the air out of sealed environments. This is the same pump I use to operate my vacuum cannon seen here: http://youtu.be/CVL99yIB3NQ A clear vacuum chamber such as the one seen in the video can be obtained by
From playlist Practical Projects & Skills
Steam Vacuum - Making/How it Works
A steam vacuum is a vacuum that's create by making steam in a container (I use a microwave and a kettle) and then rapidly cooling it back to water (condensing it), leaving behind a vacuum. This vacuum is a low pressure are that dramatically sucks in more water and, if in a flexible contain
From playlist Science Projects
Gravity Filtration and Vacuum Filtration
The first laboratory technique that we will learn together is a very simple one, filtration. This is how we separate a mixture of liquids and solids. There are two common ways a chemist will perform filtration, those being gravity filtration and vacuum filtration. These are very easy to un
From playlist Chemistry Laboratory Techniques
Now You Know: Bursting Balloons
When you stick a needle in a balloon, the rubber tears—the balloon pops. But high-speed video reveals the details, and there are some surprises to be had. How does the rubber unzip as it tears? It’s different for a round balloon and a longer balloon-animal balloon. And if the balloon is fi
From playlist Now You Know
What Happens When You Put Bubble Solution In A Huge Vacuum Chamber?
In this video I put bubble solution in my vacuum chamber. I don't need to actually blow bubbles in the vacuum chamber because once it starts boiling it will make its own bubbles! Watch as the chamber fills with bubbles once I turn on the vacuum pump. The most amazing part is once it is fil
From playlist The Action Lab Vacuum Chamber Awesomeness!
Visit https://brilliant.org/scishow/ to get started learning STEM for free, and the first 200 people will get 20% off their annual premium subscription. You might think the way mammals eat is pretty simple: They open their mouths and bite the thing they want to eat. But for some marine ma
From playlist Biology
This is the first test of the flapturbine in water. Even though the device is designed from simple components it performed well. We believe that this device could be used for tidal energy production as well as producing power or pumping water from rivers. You can find more detailed info a
From playlist Turbines
Phillis Wheatley: Crash Course Black American History #7
Despite all the hardship of being a Black person in Colonial America, some Black people were able to defy the harsh conditions and create art. Today we're learning about a teenager who attained literacy and wrote poems that reached a large slice of the population and helped changed the way
From playlist Black American History
To learn how I made the vacuum pump used to operate this cannon, take a look at this video: http://youtu.be/UkPLu6mgdWA A vacuum cannon is an interesting physics demonstration that shows how much atmospheric pressure there is at the earths surface, though we do not feel it because our bod
From playlist Science & Experiments
Chinchillas! What, Where, and How
Jessi shares what Chinchillas are, where the come from, and how to care for them in captivity. Featuring Cheerio the chinchilla! Chinchilla Introduction Info: http://www.chinchillachronicles.com/introducing_chinchillas.html Our Video Sponsors: Barbara Lea Weaver-Mercado Robert K. Jer Ka
From playlist What, Where, and How
Lucie Green presents, The Expansion of the Sun, at Ignite Sci Foo 2011
From playlist Ignite Sci Foo 2011
Slavery in the American Colonies: Crash Course Black American History #2
In the 17th century, as the British colonies in the Americas were getting established in places like Jamestown, VA, the system of chattel slavery was also developing. Today, we'll learn about the role that slavery played in early American economy and how slavery became a legally accepted p
From playlist Back to School - Expanded
Preserving Lonesome George Short Doc
As the last survivor of his species, Lonesome George became a worldwide icon of conservation decades before he died from natural causes in the Galapagos in 2012. When the Pinta Island tortoise arrived at the American Museum of Natural History in early 2013 to be preserved, Museum scienti
From playlist Earth Day
Experimental Methods: Flow visualization (Part 1) by Jaywant Arakeri
Summer school and Discussion Meeting on Buoyancy-driven flows DATE: 12 June 2017 to 20 June 2017 VENUE: Ramanujan Lecture Hall, ICTS, Bengaluru Buoyancy plays a major role in the dynamics of atmosphere and interiors of planets and stars, as well as in engineering applications. This field
From playlist Summer school and Discussion Meeting on Buoyancy-driven flows
The Natives and the English - Crash Course US History #3
In which John Green teaches you about relations between the early English colonists and the Native people they encountered in the New World. In short, these relations were poor. As soon as they arrived, the English were in conflict with the native people. At Jamestown, Captain John Smith b
From playlist US History
Air bubbles sink and steel spheres rise in an unusual fluid
Counterintuitive effect occurs in mixtures with both liquid and solid properties. Learn more: http://bit.ly/2gSTqfL
From playlist Materials and technology
Bubbles | SciShow Tangents Podcast
Kids Month floats on as we talk about possibly our lightest subject ever: bubbles! Pop in to learn what makes a simple soapy membrane so fascinating to kid and adult like! Want more SciShow Tangents? Check out hundreds more episodes of our podcast here: https://scishow-tangents.simplecas
From playlist SciShow Tangents
The Germantown Petition Against Slavery: Crash Course Black American History #5
In 1688, in Pennsylvania, a group of four men created the Germantown Petition, which made the case that slavery was immoral and that it was inconsistent with Christian beliefs in general, and Quaker beliefs specifically. While the petition wasn't ultimately adopted by the Quaker hierarchy
From playlist Black American History
Progress on vacuum chamber build - helium leak detection, custom flanges
I machined a few custom aluminum adapters for KF/NW vacuum fittings on the lathe this weekend. Next time, I hope to have electrical feedthroughs and should be ready to start depositing material!
From playlist Mechanics