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Questions tagged [materials]

Material is a general term for a chemical substance or a mixture of substances with certain, well defined physical properties.

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What is wrong with storing deionized water in glass containers?

I have heard that in general storing deionized water in glass bottles is ill advised and that it is better to use plastic. Additionally this is especially important for water used in ICP. I have ...
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Where can I look for a short chain photopolymer?

I am by no means an expert in this field, so please be patient with my explanation. I am looking for a photopolymer with very specific properties. I am not sure how realistic it is to find such a ...
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Properties of poly sponge vs. poly foam?

Question: the aspects in which I'd like to know how the poly sponge compares to the poly foam are: Stretchability (e.g. compression, then rebound back to original shape). Durability as they keep ...
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How can I prevent my spin-coated silica thin film from cracking when I heat it up?

I am spin-coating a porous silica solution on a glass microscope coverslip, and then heating the resulting thin film to $\pu{350 °C}$, in an attempt to create a thin film of porous silica sol gel. I ...
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42 views

Do self-growing hydrogels grow and strengthen infinitely?

Recently, there was a publication [1] (/., YouTube) on self-growing materials using mechanoradically-generated double-network (DN) hydrogels, closely resembling self-strengthening of muscles. We ...
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63 views

It is possible to create any metal? [duplicate]

This question just popped up in head. There are many things which we are good at. We are good at: constructions. build stuff. destroying things. repairing things. cleaning. But I want also to know, ...
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Why can a diamond be broken using a hammer if it's the hardest natural substance known?

I've heard that diamond is the hardest natural known material but, on Google search, I found that it can easily be broken by a hammer as it's not tough. So, what is difference between hardness ...
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Materials used in cooktop heating element, and reason for black appearance

I have been interested in the structure of heating elements/coils used in cooktops. I am referring to something such as in the following picture: I have a cooktop at home with such elements, and at ...
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2answers
48 views

Directional emission from molecules

This might be a silly question (probably is). When a molecule absorbs it has a transition dipole moment, a measure of how strongly a certain transition will interact with light will depend on how ...
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2answers
276 views

Why is FEP transparent and PTFE not?

fluorinated ethylene propylene (FEP) is close relative of poly(tetra-fluoroethylene) (PTFE), both only contain fluorine and carbon atoms,both have very similiar properties yet FEP is relatively ...
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1answer
93 views

Does alumina become transparent at high temperatures?

Consider a normal opaque alumina crucible. I've heard that they become transparent at higher temperatures and therefore, are not appropriate for high precision DSC (caloric) measurements. The reason ...
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2answers
106 views

Which is the cheapest plastic that retains its structure at 85 °C or higher temperature?

In an academic project, I need to protect some electronics components from heat (around 85 °C). I am searching for both a cheap plastic film and a cheap plastic to be used in a injection molding ...
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1answer
47 views

Liquid that burns in a vacuum [duplicate]

This may seem like a silly question, but is there a flammable liquid that could oxidise itself, so it could effectively burn in a vacuum?
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3answers
1k views

Why are calorimeters often made of materials with low specific heats?

When building calorimeters, a material with a low specific heat is often used (such as Styrofoam, aluminum, etc.). However, why would a material with a low specific heat be preferred? My thought ...
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1answer
37 views

What does it mean for a higher glass transition temperature in terms of crystallinity?

The glass transition temperature is associated with amorphous regions in a polymer. If I have observed in a lab experiment that polymers with a higher glass transition temperature tend to have less ...
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1answer
171 views

Which invariant reactions are congruent?

I am studying the concept of incongruent melting and invariant reactions. I was wondering, would all the invariant reactions that I show below be incongruent? As I understand it, we can only have ...
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1answer
120 views

Equation to find specific gravity (or density) from a solution of sugar and water

Is there an equation or simple way to calculate the final density of a solution made from x grams of sugar and y liters of water? And would it work in reverse? if we have y liters of water at z ...
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1answer
89 views

Can I use pure zirconium as an anode in electrolysis?

I read that zirconium is not very reactive even when supplied with a current in an electrolyte. If I had a sizable piece of it, can I use it to perform electrolysis for rust removal of items? Would it ...
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1answer
48 views

Help with Carbon Fibre

I'm having trouble finding articles about carbon fibre that don't contradict other articles. I just have a few questions about the atomic structure and the intermolecular and intramolecular forces. ...
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1answer
41 views

What material most closely resembles/emulates dog's excrements? [closed]

Please get me right - this is no joke! Our engineering team has a terrible contract - we need to find a way to get height from which some dog excrements were dropped judging by what was found on ...
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1answer
63 views

How to correctly mix solutions?

Imagine you have two ingredients - 45 grams of 60% ethanol, and as much water as you wish. The only accurate tool you have is a scale, which measuring error is up to $\pm \pu{1gram}$. How would you ...
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1answer
53 views

Hazards of trivalent chromium and hexavalent chromium

I am examining a material safety data sheet that reports on trivalent and hexavalent chromium in chemical films. It covers each type where it is used in a product individually. Is there a practical ...
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1answer
32 views

Composition of Portland Cement before Hydration [closed]

I recently came across a question- Which of following chemicals is NOT found in Portland Cement? A. Di-calcium silicate B. Tri-calcium silicate C. $\ce{CaSiO3}$ D. $\ce{Ca3(PO4)...
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1answer
29 views

What is spatially and chemically heterogeneous materials?

Follow this paper, Structural analysis of humins formed in the Brønsted acid catalyzed dehydration of fructose They explained "humins are spatially and chemically heterogeneous materials." I found ...
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Long-term durability of linen vs polyamide vs polyester?

What is the comparative long-term durability of linen vs polyamide vs polyester when exposed to oxygen, but not sunlight? I assume that linen, polyamides (Nylon) and polyesters will all oxidize and ...
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56 views

PTFE-to-PTFE or PTFE-to-Copper pressure seal

I am currently working on an engineering project with a friend. Without giving too much away, I have two parallel strips of Zirconium-Copper alloy sandwiched between an upper and lower piece of smooth ...
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Is there a known crown ether analog to fullerenes?

It is well known that endohedral fullerenes have potential quantum computing applications example 1,example 2, and example 3. But, currently they are too expensive, around $167 million per gram at ...
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1answer
59 views

What is the definition of a component in a phase diagram?

I have been trying to understand the concept of a component in relation to phase diagrams in my materials class. I have tried searching online and found that the definition is supposed to be that a ...
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Study long term properties of two polymers

This is a material-science question, and I didn't know where else to put it. I (and two others) are mechanical engineering students and are starting a bachelor's thesis which involves some material ...
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60 views

What material can be used as scraper in a chemical reactor?

I am having a 10L reactor built using SS316 for Plastic Pyrolysis. TEMPERATURE : 550C I would like a scraper to clean the char that forms on the reactor's inner layer. Teflon scraper is available ...
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1answer
32 views

How would ceramic coating inside the reactor affect heat transfer? [closed]

With the ceramic coating, would I be able to get its internal temperature raise upto 520. I would like to get a reactor fabricated for plastic pyrolysis. The temperature would maintained around 520C. ...
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1answer
467 views

How does PEDOT:PSS work (mechanism) in Organic Electrochemical Transistors?

I have a question about the fairly fundamental theory behind the application of PEDOT:PSS in an organic electrochemical transistor (OECT) device. As at least I understand it, the ...
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1answer
117 views

Is matter really divided in two categories?

Page 1 of almost every Textbook start with the ordinary divison of matter in 2 categories: Substances and Mixtures. Substances, or Pure Substances sometimes, are defined as a form of matter that ...
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1answer
268 views

What type of gloves should be used while diluting sulfuric and hydrochloric acids?

What type of gloves should we use on hands while diluting sulfuric and hydrochloric acid? Can we use these gloves in chemistry lab to handle other acids?
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Thermophysical properties of liquid Galden LS 230 between 25 °C and 230 °C

I'm looking for thermophysical properties of Galden LS 230, a liquid polymer (PFPE) produced by Solvay (https://www.solvay.com/en/markets-and-products/featured-products/Galden.html) at temperatures ...
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2answers
86 views

Material that changes solubility when electric potential is applied [closed]

I am looking for a material witch is easy to deposit in thin films and which changes its solubility if a electric potential is applied. Do you know of any such materials ? EDIT: This is for what I ...
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Can such material exist? [closed]

Can a solid material exist, such that it shatters if you hit it lightly (with a solid object) but it deforms and doesn't shatter if you hit it hard (say with a hammer)?
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1answer
74 views

Uncertainty in measuring the mass of the palm oil and the base in saponification

I am a student coming from the domain of mathematics, and I am working on error analysis and uncertainty, but I have a question in the domain of chemistry. I am studying the effect of the ...
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1answer
498 views

What gas has the highest refractive index? [closed]

Coming from this answer on the Worldbuilding stack, I'm trying to find a gas with a high refractive index in the visible light wavelengths. The highest index on this site, is chlorine at 1.000773. Is ...
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1answer
42 views

Material with refraction index similar to Si

I am looking for a material with a refractive index over the visible spectrum , which is close to the refractive index of Si, but which does not oxydise in air. Do you know of any such material ? ...
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1answer
205 views

Isotopic mass to density

I want to figure out/calculate the density ($\pu{g/cm3}$) of the various isotopes, here $\ce{^109Ag}$. I know it's isotopic mass is $\approx109$ and calculated the number of particles/gram. But I ...
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Extraction of Activated Carbon from Lignin

I'm currently working on a research project which involves the extraction of activated carbon from lignin. I'm already aware of the method of preparation using an alkali along with lignin products but ...
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491 views

How can I extract cellulose in plants using acids?

Me and my classmates are doing a research project about the extraction of nano cellulose from plants to form a biocomposite, which can be a material to form an effective biodegradable material. We've ...
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1answer
89 views

Why does a protein crystallize with a specific salt but not with another?

So I am conducting an experiment and I do not understand this super fundamental part. I know salting out works via solubility, and I know crystallization works via ordered structures. But could ...
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2answers
247 views

Brass Instrument: Dezincification or just scrubbed off?

I do own a brass instrument (a trombone). The lacquer is damaged. I asked how to deal with it here. Now I learned that the brass contains zinc, and there is a corrosion process called "...
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0answers
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Accurate way to tell a material is PP with easily available means? [closed]

Sometimes even though certain products that I bought come with a "PP 5" marking on it, I suspect it may not be the case, so I wanna know, is there a relatively safe and accurate way to tell if certain ...
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0answers
44 views

Reducing the thickness of a layer of elemental sulfur

I want to make a very thin film of elemental sulfur. While mechanical polishing can bring a film to 10 microns in thickness, but I need to bring my thickness lower (hundreds of nanometers). Although I ...
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1answer
115 views

Phospors and Phosphorus

I'm not a chemist. I understand that phosphorus comes in multiple forms, one of which is white, volatile, and highly toxic. I know that phosphors come in multiple chemical forms, two of which are ...
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1answer
62 views

Harnessing phase separation to easily make Li film

I want to make a thin, smooth film of pure lithium in a glovebox. In general, I think that I can use a phase separation approach. I will heat a bath of mineral oil above Li's melting point, then ...
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Pseudocapacitive behavior in EC electrode materials [closed]

As we know in electrochemical capacitors or supercapacitors, the basic electrochemical signature is CV (cyclic voltammogram) curve. Some materials like $\ce{RuO2}$ and $\ce{MnO2}$ have a capacitive-...