Material Definition and 1000 Threads

Good evening, I'm an undergraduate astrophysics student currently doing research, and I wanted to get the opinion of some knowledgable chemists about a particular reaction my professor and I wish to emulate. Using a specific type of laser (Nd: YAG, for example), I'd like to mimic something...

Hi, To begin with, I am not a native English speaker and have very limited knowledge regarding magnetic fields and thus want to apologize in advance for probable use of incorrect terms. http:// In the picture above, M represents a magnet. S is a material that is not allowed to be affected by...

Is there any real-world material that is both reflective and transparent in 3D? A simple plane of glass is 3D and transparent, but reflective only in two 2D planes. I'm looking for something that is reflective in a large number of parallel 2D planes so that the reflection has depth. How...

I teach soil mechanics and I introduce to my students brittle and ductile materials. Failure of brittle materials is obvious for them but not for ductile materials. Do you know any ductile material that can be easily broken by traction? Unfortunately I do not have any tensile testing machine so...

I am doing a project that relates to welding acrylic. I got the bottle today, and I can't use it because its flammable and has chemicals known by the state of California to cause cancer (makes you wonder why the hell they would market this crap). Are there any clean, non-flammable, and...

And what is the difference between refractive index and absolute refractive index? Why do we use relate two absolute refractive index to find the refractive index of a particular material say we need to find refractive index of water with respect to ice.and why do we always put the higher value...

This system consists of a shaft that is connected to a motor that is rotating at 200rpm. The whole shaft consists of two gears. The input power of the system is 500W. Is there a way i can calculate how exactly i can find the best material for my gears that is able to withstand the input power...

Hi. I am re-engineering a 40+ year old carburettor design. The current throttle slide has stress raiser flaws and is the same material as the mixing chamber that it slide interfaces with. The prototype slides were printed in ABS for fitment trials. The functional trials used Acetal allowing for...

Hi All, I have been taking a class recently, and for some reason or another, professor has chosen not to return neither assigned papers nor exams , although some homeworks have been returned. I brought it up and got a non-responsive answer to the effect of "we cannot just do that". I have...

Homework Statement The half life T½ of Carbon-14 is 5730 years. What is its decay constant? After what length of time will 35% of an initial sample of Carbon-14 remain? Homework Equations Decay constant λ= 0.693 / T½ Where N = amount of radioactive substance, N=N0e-λt The Attempt at a...

I have observed that certain materials can drive fluids into themselves and push their own molecules apart, thus inflating itself. When, I try to reason, I'm not quite successful. Even if there is surface tension or under atm pressure, extension of intermol. distance is departure from...

I know almost nothing about engineering, so my question is very basic. Basically, assuming that I have a scheme for a prototype of something, how do make it from a raw material? If it is still not clear what do I ask, let me further simplify. Suppose that I want to make a well-shaped iron ball -...

ZrO2 is an ionic conductor used in automobile engine control systems. At 800oC the mobility of Zr4+ is 0.01m2/V.sec, and of O2- it is 0.04 m2/V.sec., there are 4.5 x 1017 mobile Zr4+ ions/m3, and 2.0 x 1018 mobile O2- ions/m3. What is the conductivity of ZrO2 at this temperature, in S.m-1...

Homework Statement I am doing an assignment with multiple heat transfers, and have to investigate the effects of including thermal radiation vs saying that thermal radiation is negligible. I know that the equation for thermal radiation is q = A*σ*(T14 - T24) (*) In my case the equation...

I'm looking for a material to use as a light shroud for a joint between a spectrometer and camera. Basically, I want something that is flexible, opaque, black, and fairly thin and not too fragile and something I can readily buy. Do you know any such material? I have used Poron foam before which...

Hi I am about to fabricate a part exposed to super critical water (600C & 250bar). In the past people have been using titanium or convoluted methods to prevent excessive corrosion induced by dissolved solids (principally Cl-), which under supercritical conditions precipitate, coming back into...

Homework Statement Or is it only valid in vacuum condition? Segment of straight wire carrying current I (at distance r) dB = u.Idl x r / 4pi . r^2 (I've came across it on a book about Maxwell's Equations.) Homework EquationsThe Attempt at a Solution Does correction have to be made for...

I need some advice on my design for a tablet holder that I want to get 3-D printed using a printing service, not my own printer. I need to decide which material to use and how thin I can make it. I asked for advice already on a 3-D printing forum, but they could only tell to find out through...

I have a hollow 2024-T3 rectangular bar and need to check its mechanical and physical properties. So i went through the MIL-HDBK-5J, and it have 3 choice for this material; 1. Sheet 2.Drawn tubing 3.Extruded Bar,rod,and shapes. so for hollow rectangular bar, which one should i choose. 2 or 3...

My series foundation is really weak, and this spring I'll be taking Differential Equations. I know series plays a big role in solving some ODEs, so I'll be re-learning the material from Calc 2 to make sure I'm up to par for the class. I'll be working through Stewart's chapter on series but was...

hi, I have studied the general expression for metamaterial as n=√(εμ) for dielectric relative permeability is one and we have n=√ε, but what would be the refractive index for magnetic material , by seeing symmetry I figure out as n=√μ will it be valid and we have Lorentz model for dielectric...

I'm currently studying from a rented Stewarts Multivariable Calculus: Concepts and Contexts however for single varibale calculus I used a lot of different sources for study Kahn, Mooculus and Pauls. I've been self studying calculus for for about a year and a half now. In regards to moving to...

Does anyone know which formula is used or how to arrive at the righthand side of the equation below, which is the dot product of del and rho*a 2nd order tensor(V V). . represents dot product and X a vector quantity This problem is in connection with transforming cauchy's equation in terms of...

Anyone have any suggestions on other [mold-proof] materials that might be good to diffuse moisture (distilled water) into a vessel? For a project, I am trying to create a re-humidification vessel to re-humidify certain materials that have dried out, and am trying to think of the best material...

I am doing the Bottle Rocket event for Science Olympiad and I have to have an egg strapped to an air pressured rocket which should not crack on the way down. What is the best and lightest material I can use to absorb the impact? I was thinking of a sponge or cotton. The rocket will be floating...

I'm not sure if I'm supposed to post this here, if I'm not, I'm sorry. That being said, what kinds of rubber can be heated up to 30 degrees c without degradation but can be melted. I would like to sandwich a heating filament between two sheets of rubber and seal them together with heat.

Good evening, forum members... I'm currently enrolled in an Engineering class in my school and I'm considering engineering as one of my career pathways, but I would like to know the good, the bad, and the prospects of an engineering career before making a decision. I'm also interested to know...

Transparent materials such as glass can let visible light pass through nearly undisturbed. I don't understand how photons just pass through atoms in that material. I can understand the concept of atoms not absorbing the photons in that specific wavelengths, but how can photons avoid deflection...

I sent a summary about ultrasound elastography to my teacher and somehow I wrote incompressible material in my paper. now he wants me to really explain him what is Incompressible material. I looked at internet about compressibility and Poisson ratio but doesn't still give a good understanding...

i am new to rubber components , now i am developing a bladder for pulsation dampener, so for that i need to check the spring rate or elasticity of viton material and to determine the thickness for the bladder, I am struggling a lot to find the shear modulus of rubber, if have this valve i have...

Hi, is there any independent research group I could tap into in thermal and material engineering and general physics. What are the credits and funding I could get from it?

I am currently in my second year of a bachelor of science with a major in physics. The class I am taking is notorious for being hard and the professor is very hard to understand (understanding the material, not what she's saying). The class is all about oscillations and waves. The textbook is...

Consider the Lindhard response function: \chi(\vec{q})=\int\frac{d\vec{k}}{(2\pi)^d}\frac{f_\vec{k}-f_{\vec{k}+\vec{q}}}{\epsilon_\vec{k}-\epsilon_{\vec{k}+\vec{q}}} where ##\vec{q}## is the wavevector, ##\epsilon## is the free electron energy and ##f## is Fermi-Dirac distribution function. For...

I am manufacturing a plastic cube out of six flat, hard pieces plastic, of the same consistency as water bottle plastic. The top and bottom sides of the cube will be connected to the middle 4 panels by condom rubber. I need some kind of bendable plastic that can expand so that the cube can grow...

... transparent to sound. Hi, I am looking for a material that will have almost zero effect on the degradation of a sound wave as it passes through. It must be a flat surface. It will be used like this: Can any of you materials guys think of anything that would work? Thanks for any ideas.

Would SS304 or SS316 be a better choice for a reactor containing 200 kg/hr sulphuric acid (97%), 2000 kg/hr methanol (98%) and 3500 kg/hr free fatty acids mixture? My initial choice was SS304 since the sulphuric acid amount was little, but upon reading more on methanol, I'm considering about 316...

Homework Statement Find the general solution to the equation. Homework Equations (dy/dx) - y - e^3x=0 The Attempt at a Solution [/B] I rewrote this as dy/dx - y = e^3x This is a linear first order ODE, in the form dy/dx + P(x)y = f(x) P(x) = 1; f(x) = e^3x The integrating factor =...

I've been trying to build a closed system water electrolyser with easily available materials which allows me to collect the gases separately. To do so, I've been meaning to build an acrylic housing with a textile separator in the middle of two compartments which houses the anode and cathode. The...

Homework Statement The prisms have a refractive index ##n_1=1.3## at wavelength ##\lambda=300nm## and are connected by a material with refractive index ##n_2##. What is the refractive index ##n_2## so that light of wavelength ##>\lambda## follow path 2, and light at ##<\lambda## follow path 3...

Hi everyone, I just wanted to know/understand that, why do the dielectrics don't get polarized, when subjected to induced electric field ? Because, according to the definition of electric field(which is a vector), it is the force per unit charge, which implies, that electric field has a unique...

what about a material causes it to be shiny and reflect light. would it be reflecting 100% of the photos when the material looks bright white i.e. shiny. what about the atoms in the material causes the material to be shiny? can any material be shiny? why do shiny objects the part that is...

So, I am watching this show about airline crashes and apparently, a A380 has gone down because the speed limiter on a spinning engine rotor broke, and the part spun so fast its ultimate yield strength was reached and the material shatterted. Thats got to be one really fast spinning rotor! But...

Hello everyone. This is my first post.. I have been given the task of building some large RF reflectors that will reflect 35GHz RF energy. Can anyone give me an idea of what material / thickness of material I could use. For an example.. Would a pyramid made from wooden pallets covered in...

Well what I want to ask is that If someone does graduation in material science. SO WHAT kind of job he/she gets.? Infact what is material science what is being studied in this subject.?

Homework Statement Water corresponds to approximately 20 vol.% of the bone in mammals. On a dry weight basis, approximately 70 wt.% of the bone is composed of carbonated apatite. The density of apatite is ~3.0 g/cm3. Density of dry collagens is ~ 1.2 g/cm3. Calculate the volume percentages of...

Hi everyone, I know this is a standard textbook question but I am really wondering whether I am wrong or not. My solution is shown as below but can anybody please give me some opinion? Cause I think it is too simple for this question...Thank you so much. Water corresponds to approximately 20...

Looking to build a bike frame that is made of transparent material. Must be able to safely hold up a rider like typical steel frames. Any suggestions?

I don't actually find this probable, it was merely the most concise way of phrasing my concern. In the linked description of the mechanism of transparency (), it is stated that opaque objects do not allow light to pass because the incident light is absorbed (as photons, naturally) in the...

Consider a block of a piezoelectric material sandwiched between two parallel plate conductors, sort of like a parallel plate capacitor with a piezoelectric material as its "dielectric." If applying the same pressure to two of these configurations, does the thickness of the piezoelectric block...

Is it made of quartz or stainless steel/aluminum or what? Does it matter which?that's all I need to know, I just can't seem to find if they can be made of standard vacuum metals or if they have to be quartz. Only really seen some diagrams mention quartz tubes but the pictures of large ones seem...