Material Definition and 1000 Threads

I was wondering if anyone has ever tried to model/fit a crack on a material surface with a Weierstrass function.

What material is most suitable as a filler for pillows, which material can provide optimal comfort and neck support? Examples of Filler Materials: Feathers Buckwheat Cotton Cloth Fibers Synthetic Plastic Fibers Foam Viscoelastic Foam Memory Foam Latex Compressed Air Examples...

I was pondering this while I was staring at a salad dressing bottle at home (an oily dressing that doesn't stay mixed when untouched for a period of time...), how well could you mix (shake up) a bottle with different oils in a micro-gravity environment, if at all? Moreover, my actual question...

Is there a type of piezoelectric material that only produces a current when bent one way or only bends one way when applied a current?

Hello Everybody I want to do the comparison of metals like Silver, Gold, Aluminum, Copper, Sodium and Potassium as plasmonic metals. Now, I am confused about some parameters about what they really mean. 1. what does ε(int) means? Is it better for a plasmonic material to have less ε(int)...

Homework Statement Suppose we have a lens of known focal length, f=100 cm. (a) If light enters the lens from air, but after the lens enters a medium with index 1.33, how far from the lens will focus? (Assume the incident light is collimated.) (b) What if there is instead air after the lens...

I am looking for a material that will change colors depending on how long it is in the sunlight. Any thoughts?

Hi! How can I tell, based on my Raman and X-Ray Diffraction studies, if a thin film is nanocrystalline or amorphous? The maximum thickness of my films is about 200nm, the XRay diffractograms showed nothing but the substrate (is it because of the thickness?), and my Raman spectra showed some...

Are there any easy to obtain and fast responding photoresistors out there ? The resistance of material must decrease when light in shining on it, and the response must be fast. Note: I know that photodiodes respond extremely fast but they must be used coupled with a transistor to amplify the...

Hi all. I am doing a project in which I have a 99%clear transparent Silicone sheet. LEDs make light pass through this material which is than picked up by phototransistors on the other side. when someone/something touches the Silicone, this deforms and the phototransistors pick up different...

What happens when radio waves of around 1900mhz (cell phone) is confined in an aluminum box. Will the waves be able to pass through the box to the outside. What would be the best way to get the waves to the outside of the box with only modifying the box. If i cut a hole would that improve how...

I want to learn some basics of Computational Fluid Dynamics.But most of the books that I found dealt mostly with the theory of it with very less examples or problems to be solved numerically. I know Matlab and am pretty good at coding too.So, I am searching for a book from which I can learn CFD...

What is the name of this parts and what is the material is used to make this part? http://upload.wikimedia.org/wikipedia/en/8/8c/Stone_Grinder.jpg Thank you

I wonder what is the material is used to make an electronic chip? http://datasheet.seekic.com/ImageFile/MCP/Microchip_MCP4922-E_ST85280.jpg"]Image[/PLAIN] of an electronic chip. I also would like to know what is the material of the bottle of the coca cola soft drink? Is it pure silica glass...

Why the ground state HOMO level of a molecule with two opposite-spin electrons, is singlet while we know that a level with two opposite-spin electrons may be singlet(s=0,m=0) or triplet(s=1,m=0)?

As you know,the set of light wavelengths that a material is transparent to,is sth dependent on the properties of the material.My question is,can we find a material which is transparent to a specific wavelength range? For example,I want a material,which,among the visible light wavelengths,is...

I am in process of doing a project for school. The basic aim of the project is to address the following issue. I live in a country where we have a lot of street vendors and beggars that stand in the street at night and as a result are not visible to oncoming traffic. i would like to create a...

I need help exploring this question: what makes a solid transparent/opaque? If I have clear sheet of plastic and I introduce imperfections (such as small air bubbles inside), it turns white if the # of imperfections is large. Is it possible to maintain the polymer transparent with such air...

Hello, I am looking to read up on some popular science kind of books on Materials Science and Engineering. Something on the lines of "future of materials" or "materials of the future". Does anyone have any recommendations? Thanks

What is meant by the sub-material? Such as if you mix three differential materials, for example, coffee + sugar + water, which one them is the sub-material? Thank you

Hello, I was wondering if anyone could tell me of an easily available (to a primary school teacher) solid material that conducts electricity, but noticeably poorly, so that it can be demonstrated and hopefully performed by 9 year olds. To be exact, I want a solid material that can be...

Hi all, I am looking for the best material for IR (infra red) absorption, preferably something that I can make it into a thin film; any material that would work from semiconductors, metals to more exotic materials like graphene or... I appreciate your help. Thank you

Homework Statement A) To= 35 °C find α And β B) determine the temp in which this material becomes a super conductor as predicted by the equation below. ρ=ρ0(1 + α(T-To) + β(T-To)^2)To= 35 C. ρo=2.5e-8Ω m T1= 0 C. ρ1=2.346e-8Ω m T2= 100 C. ρ2=3.036e-8Ω mHomework Equations ρ=ρ0(1 +...

Homework Statement I am trying to enter the strain and stress properties of a piezoelectric material, I only have d31 and e33 constant with no dielectric constant. I don't know how or where to enter these values in Abaqus since it ask for a Matrix. Homework Equations The Attempt at a...

Hey everyone! I am currently working on a project regarding the synthesis of variously substituted isatins using the Sandmeyer methodology, involving the condensation of chloral hydrate, hydroxylamine and substituted aniline (in this case the 4-ethylaniline) to nitrosoacetanilide with...

Hi everyone, I got some past papers to revise for my second year final exams in may the course I am in is called electrical and electronic engineering (I am studying in the uk). I was just hoping if any of you guys know any good youtube channels like khanacademy but for engineering topics...

Hi, I'm looking for a good beginner text on Wavelets. Preferably an undergraduate or early graduate level. The background material that I'm missing most is infinite dimensional vector spaces/function spaces and Fourier analysis. Any advice would really be appreciated! Thanks!

In the future I would really like to enroll in an aerospace engineering course and I was wondering if there are any good books out there which cover the important parts of this discipline? I came across the following page which contains some of the topics that will be taught in university (at...

So basically I'm not sure of the solution and just want someone to tell me if what I did is correct. It's important I have an upcoming exam. Thank you.

Is there any material or book that explains how one could go from data to differential equation comprehensively? More like functional data analysis+differential equations

Hi, I will be enrolling in an Analysis I course (highly theoretical calculus course, emphasizes proofs) at UofT this upcoming fall and was wondering if there are any materials that can adequately prepare me for this course.

Hi All, I'm wondering if anyone is aware of a piezoelectric material that is both liquid and is transparent/colorless/ lower refractive index? Is there database online where I could compare these values? Google has not been kind to me:( Any help would be so appreciated.

Right now I am working on a small project. I have a board (made of PVC) that is nearly 3ft long (1ft wide) and supported on each end. Mounted to the board will be various items. To save money and weight I am looking to calculate the minimum thickness I need so that the board can support...

Is there any material that can be ionized (plasma state) at realtively low temperature, say 30 or 40C?

Time and time again I am forced into purchasing a new hockey stick simply because the bottom of my hockey blade wears out. This is a common problem with any hockey stick which hockey stick manufacturers love as it keeps you purchasing more sticks frequently. Are there any suggestions of a very...

Lets say you have a block of iron with a mass "m" exposed to an infinitely strong magnetic field "B." If there was a strong wooden interface preventing this iron block from moving towards the magnetic field source, how can you calculate the force the iron block would exert on the wooden board?

I'm currently designing an observation deck as a project. We have to consider a strong, light and cheap material that will hold 15<x<25kg. I considered bamboo, any other ideas?

Hi, I want to use piezoelectric material to harvest compression energy, i need to calculate the power output but i can't find enough information on the web to figure it out... First, I want to learn how to calculate the power output of piezoelectric material using d33 and g33 data...

I'm interested in building a forge, mainly for flux crystallization of corundum (ruby/sapphire), but I want it to be versatile. General Requirements: Withstand temperatures up to 1400 C (2550 F) for months at a time (crystallization can have very slow kinetics) Walls with a thermal...

Hey guys, I am new to this forum so I don't know if this is the correct place to post this thread. Anyways, I was wondering what kind of material would be better for a milkshake straw. Would a highly thermal conductive material (like silver) or a thermal resistant material (like glass) be...

As a material is heated, it increases in temperature until it enters a phase transition. During the transition, added heat does not increase the temperature. As this heat is being added, what is the substance? Is it a mixture of liquid and gas perhaps? If so, what are the proportions? In...

for my senior project in mechanical engineering .I'm thinking I'd like to design a machine for recycling .Basically ,different kinds of garbage can be thrown into it and separation of the materials for recycling is done by the machine .I'm not sure how to go about it though .I'm thinking the...

If I have a rod with a steel core bonded to an aluminum shell, how can I find the stress in the rod when it is subjected to a temperature change? I know how to find the stress due to temp change if the tool is made of the same material throughout, but how do I do it if there are two? I...

Can anyone give me links with supplementary notes and problem sets for math 55? Of course I'm no harvard student, I'm just a physics major with an interest in math. Thanks in advance! ^_^

Hi guys, I'm doing a quantitative finance research project that is based on the following papers: "Systemic Risk and Sovereign Debt in the Euro Area" - Deyan Radev (can be downloaded here: Systemic Risk and Sovereign Debt in the Euro Area by Deyan Radev :: SSRN) and "Consistent Information...

Does anyone have any information on what the clear plastic cases (lens, capsule, w/e) are made of for LEDs? Google says it is some sort of epoxy, but I also read somewhere a while ago that sometimes it is acrylic. Is this true, and can you buy LEDs anywhere that are made of thermoplastic like...

What is the Difference between Substrate & Base material in Printed Circuit Board? What is the difference between Substrate material in PCB and in semiconductor [VLSI] ?Is the VLSI substrate Cu plate? Is the substrate of VLSI a fibre glass or it is something else? What is the base...

Is there any material in the world which cools when it is heated?

Different materials emit different frequencies of radiation when heated by a source of heat such as electricity. Examples include gases and solid filaments that emit infrared, visible and ultraviolet radiation, and the scheelite calcium tungstate filaments used to produce x-rays in fluoroscopes...

Hello everyone! What materials are used for making optical filter glasses? I bought this: http://www.alibaba.com/product-gs/495852853/Digital_Camera_lens_43mm_950nm_IR.html and took its transmission spectrum. So, it reminds me a transmission spectrum of CdTe. But a-CdTe is more...