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    Space groups list

    Does anyone know of anywhere on the internet where I may find a spreadsheet containing the names of the 230 space groups? In a perfect world this would simply be a csv file containing the schoenflies and hermann-maguin notations; but I can't be too picky. Thanks
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    X-ray Photoelectron Spin-orbit Splitting

    I have some XPS spectrums that I am trying to fit (my first time doing so), using XPSpeak. I understand that for spin-orbit splitting the FWHM, line shape (i.e.% gaussian/lorentzian) must be equal (more or less), peak area ratios set (i.e. 2:3 for 3d3/2 and 3d5/2), and the peak separation...
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    Determine density of states from an XPS spectrum

    I've heard any many places that the density of states (DOS) can be determined from an x-ray photoelectron spectroscopy (XPS) spectrum. Perhaps someone more knowledgeable than me can explain how this is done, or can direct me to a good resource? Thanks!
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    [Thin-Film Optics] Incident white light to color

    I figured it out using the method described in sec 6.1 of along with my own implementation in python.
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    [Thin-Film Optics] Incident white light to color

    I found this: an online calculator that calculates the reflectance of a multi-layer system. They mention they used the "complex matrix form" of the Fresnel equations. I'm guessing that means the scattering/wave-transfer matrices?
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    [Thin-Film Optics] Incident white light to color

    Bad word choice I suppose, the top layer is somewhere in-between transparent and opaque.
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    Online Materials Science Resources

    I would suggest:
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    [Thin-Film Optics] Incident white light to color

    I would imagine that in the end I want to get the reflectance as a function of wavelength which will essentially divulge the color information. To get there I'm guessing I need to first use the fresnel equations to determine transmittance/reflectance for each layer. Then use the resulting...
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    [Thin-Film Optics] Incident white light to color

    Hello, as you might have guessed, my question revolves around thin film optics. My intention is: Given a two thin-film system residing on top of a semi-infinite (bulk) layer, how can I estimate the reflecting color (RGB preferably) when illuminated by white light? (Illustrated below). I...
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    Maximum thermal cycle range to avoid onset of plasticity

    Homework Statement The linear thermal expansion coefficient of aluminum is 22.2x10-6 m/m K and that of alumina is 5.4x10-6 m/m K. If the criterion for onset of dislocation plasticity is related to thermal mismatch exceeding Burgers vector for aluminum, which is 2.8x10-10 m. What is the...
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    Electron in a potential well (numerical problem)

    Homework Statement The width of the potential well of an electron can be assumed to be 2angstrom. Calculate the energy of an electron (in joules and eV) from this information for various values of n. I believe I have messed up my units somewhere in the final calculation, but I have...
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    Ashtray suddenly fractured

    We have an ashtray on an elevated table in our balcony. No one was outside and it suddenly fractured into 4 nearly even pieces on the table. Strangely enough, all the cigarette buds were lit. This is the ashtray we used...
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    (Heat Flow) Find the Temperature and Cooling Rate

    So I will return to this step: \frac{dT}{dt}=\frac{2h}{\rho C_vr}(T_i-T_f) Which was supposed to be: \frac{dT}{dt}=\frac{2h}{\rho C_vr}(T_f-T) Since the last T now depends on time, I will need to move it over to the left of the equation. \frac{dT}{dt}+\frac{2h}{\rho C_vr}T=\frac{2h}{\rho...
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    (Heat Flow) Find the Temperature and Cooling Rate

    I think I got it now, It didn't occur to me to actually write out the thermal energy in the control volume. \frac{dE_T}{dt}=\frac{∂}{∂t}\int\int\int_\Omega \rho C_vTd\Omega \frac{∂}{∂t}\int\int\int_\Omega \rho C_vTd\Omega=(\int\int_A \rho C_vTvdA)_{in}-(\int\int_A \rho C_vTvdA)_{out}+Q+S From...
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    (Thermodynamics) Express adiabatic bulk modulus in terms of

    Homework Statement The adiabatic bulk modulus is defined as: \beta_s=-V(\frac{∂P}{∂V})_s Express it in terms of experimental variables: C_p, C_v, \alpha, \beta Homework Equations Heat capacity at constant pressure:C_P=(\frac{∂Q}{∂T})_P Heat capacity at constant volume:C_V=(\frac{∂Q}{∂T})_V...
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    (Heat Flow) Find the Temperature and Cooling Rate

    Would you care to elaborate some more? For your convenience, the photo at the bottom is from the main part of the section this problem is from:
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    (Heat Flow) Find the Temperature and Cooling Rate

    I'm really not sure, have I gone through the right process here? I didn't actually finish the calculation, I'm just curious about the process.
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    (Heat Flow) Find the Temperature Distribution

    I have a hunch that is the case since there is no mention of an IC (but I took the assumption that since there is a different T at both ends, there would be an initial T distribution, f(z)). I am not totally sure though since they didn't explicitly state "steady-state" like they do in other...
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    (Heat Flow) Find the Temperature Distribution

    EDIT: Typo, the Z' should be Z''
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    Calculate the Madelung Constant

    Here is a screenshot of my professors notes I took these equations from. This is our book: What equations would you have used?
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    Calculate the Madelung Constant

    Homework Statement Calculate the Madelung constant for an octahedral arrangement of doubly charged anions about a doubly charged cation. Use r0 for the anion−cation distance. (Hint: Remember that the Madelung constant considers the sum of Coulomb interactions over all atom/ion pairs)...
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    (Thermo) Show that in a Reversible Adiabatic process

    Homework Statement Show that in a reversible adiabatic process, for 1 mole of ideal gas P1V1γ=P2V2γ Where, γ=CP/CV Homework Equations Listed above. The Attempt at a Solution Frankly, I don't really understand what I'm being asked to do.
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    (Fluid Flow) Differential momentum balance problem

    I think I might have figured it out. Take a look at the attached pdf and double check my work.
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    (Fluid Flow) Differential momentum balance problem

    Attached pdf contains the problem, and my progress in working it. My question is, I'm not really sure how to proceed. Anyone care to push me in the right direction?
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    Fluid flow problem with the momentum balance equation

    Ooops So the answer is then: Fp = -\rhovj2\frac{\pi}{4}(D12 - D22)
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    Fluid flow problem with the momentum balance equation

    All problem info, and my work is done in the attached pdf. Basically, I'm not sure that I have done it correctly.
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    Solve Fick's second law of diffusion

    I'm curious how to solve Fick's second law of diffusion \frac{∂c}{∂t}=D \frac{∂^2c}{∂x^2}For conditions:c(x,0)=0c(0,t)=Ac(\infty,t)=0Physically this means: -c(x,t) is the concentration at point x at time t. -Initially there is no concentration of diffusing species. -At x=0 for all t the is a...
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    Resource for modelling with differential equations

    I've actually heard about that book before, but my interests have to do with engineering - particularly mechanical and materials engineering.
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    Prove the convolution of f and g

    This was the bonus question on my test, I couldn't really figure out how to begin.
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    Solve the differential equation

    I already posted this on a different website, so I'm just going to screenshot and post here.
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    Resource for modelling with differential equations

    I'm looking for a good resource about modelling for differential equations. I've completed two courses on ODE's and PDE's, but they both lacked in the applications/modelling department. Can anyone recommend a good resource/book on modelling?
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    Is My Battery Safe After Extended Heat Exposure?

    So a battery to one of my phones got left in the car (just the battery) for an extended period of time during a Texas summer. The sides of the battery expanded by a couple millimeters. But I can compress the sides with my fingers as if there was a pocket of air in between the outer tape (with...
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    Solve 3rd order ode using variation of parameters

    Homework Statement Solve using variation of parameters y''' - 2y'' - y' + 2y = exp(4t) Homework Equations Solve using variation of parameters The Attempt at a Solution I got the homogenous solutions to be 1, -1, and 2. So, y = Aexp(t) + Bexp(-t) + Cexp(2t) + g(t) I got...
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    Driving force of polymorphism

    I was wondering what the driving force behind polymorphism is. What causes polymorphic materials to change crystal structures at certain temperatures? Such as the iron phases alpha-ferrite, gamma-austenite, delta-ferrite, hexaferrum?