Questions tagged [liquid-crystals]
Questions related to matter in a state that has properties between those of conventional liquid and those of solid crystal.
22 questions
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Why can't we make liquid crystal displays out of soap?
Liquid Crystal Displays (LCDs) are widely used everywhere, especially in the screens of computer monitors, TVs, and small devices like thermostats. As its name suggests, LCDs use substances with ...
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How to use DSC to differentiate first and second order phase transition?
The DSC trace below was recorded for a thermotropic calamitic liquid crystal. The heating rate was 5 $^\text{o}$C min$^{-1}$; a heating scan is followed by a cooling scan.
Based on the previously ...
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How do dielectric molecules in a liquid phase align when polarized?
As seen in the diagram, when a dielectric material becomes electrically polarized, the molecules align themselves in a manner where the respective charges are parallel to each other horizontally.
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Can polarizing film reflect light instead of blocking light?
I was thinking about how to electorally switch glass between transparent and reflective just out of curiosity. I thought that maybe you could polarize the reflective glass in the vertical direction ...
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liquid crystal and light [closed]
The liquid crystal can be control using polarizes light. This means we can control the arrangement of the liquid crystal molecules, then when the light passes through it can be manipulated.
But why ...
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Liquid crystals for academic outreach?
I am interested in making a Schlieren texture of liquid crystals to show kids at an outreach event (see image below). I have the polarizers and camera for the imaging part, but I don't know of a place ...
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Liquid to solid crystal when exposed to air [closed]
Im working on a prototype weapon based on the needler from the Halo series. And yes while I do realize that this game series is fantasy, I still find it fun to try and recreate working versions of ...
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Can I supercool and solidify a liquid multiple times?
Let's say that I supercool a bottle of beer and then tap it so it freezes and solidifies. If I were to allow the frozen beer to melt completely, and then freeze the same bottle again, would it still ...
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Assigning labels and answering questions using given DSC graph
I'm currently working through past exam papers in preparation for my upcoming Inorganic Chemistry exam and I got to this question. We really haven't looked at DSC graphs, so I'm not completely sure ...
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Common hydrogen bonded liquids [closed]
For some experiments I need liquids with and without hydrogen bond which are pure or highly concentrated. I have only found $\ce{HNO3, CH3COOH}$ concentrated. But i need more liquids. And it would be ...
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Why is the addition of methanol during the prepartion of the liquid crystal cholesteryl benzoate necesary
Here's one way to prepare cholesteryl benzoate crystals:
Step 1 Dissolve 1.0 g of cholesterol in 3 cm3
of pyridine in a conical flask.
Step 2 Add 0.40 cm3
of benzoyl chloride.
Step 3 Heat the ...
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Why is ice sticky between −20 to −8 degrees Celsius but not below −30 °C?
I was watching an Air crash investigation video where the cause of the plane crash was determined to be due to blockage of fuel pipes by ice crystals (from the water in the jet fuel) which would have ...
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Growing crystals that are in a magnetic field or subjected to an electric field
I know different crystals resonant at different frequencies but is it possible to grow crystal at a certain frequency. An example would be growing crystals using Epsom salt or Alum in a magnetic ...
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Why does sodium polyacrylate solidify, on addition of water?
Sodium polyacrylate is a white powder with a characteristic odor. But when we add water to this powder, instead of forming an aqueous solution, it instantaneously solidifies and forms more amount of ...
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What is the explanation of the odd even effect in liquid crystals?
What is the most accepted theory for explaining the odd even effect in liquid crystals? Can anyone explain and refer the corresponding paper?
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Deformation of the nematic phase of liquid crystals surviving in the solid state
Does anyone know if I were to cool a liquid crystal with a deformed nematic phase quickly, if it will preserve the deformation in the crystal lattice?
I didn't find any information in classical ...
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Electrodeposition of Ni
How can one electrodeposit Nickel on a substrate using a liquid crystal template?
substrate is Indium Tin Oxide coated plate and the template is cetyl trimethylammonium bromide(CTAB)+WATER+ETHANOL
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What type of Organic Substance is used in LCD
I know that the liquid crystal displays contain some class of organic compound, which is somehow used to polarise light to make contrast variations(In calculator displays).
My Question is What type ...
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What are the key chemical structures of liquid crystals used in display technology?
The majority of current flat screen TVs and computer monitors are based on Liquid Crystal displays.
Liquid crystals are compounds that orient under an applied electric field and alter the ...
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How to determine whether a compound is gas or liquid or solid? [closed]
My book says, methyl chloride, methyl bromide, ethyl chloride and some cholorofluromethanes are gases at room temperature, whereas higher members are liquids or solids. Why?
With this question, I ...
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Why do liquid crystal displays (LCDs) visually distort under pressure?
A venerable question, as old as LCDs themselves. I assume it has something to do with pressure-induced changes in the path length across the display, but that's just a guess. Of particular interest to ...
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Liquid crystal current flow
In a liquid crystal cell used for LCD the conductive substrates, usually made of ITO, are in contact with the liquid crystal. The question is: when a voltage is applied to the electrodes to reorient ...