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    How to program a Pulse generator

    Hi there! is anyone here working with a pulse generator? I have Agilent 8114A Pulse generator i want to vary the frequency automatically like 1.1Hz to 10.1Hz with 1-2 secs delay. This pulse generator have a HP-IB bus at the back that can connect in a PC. Base on the Manual it can program using...
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    Resonant frequency of Piezoelectric material

    So i have a piezoelectric film deposited in the metal substrate and i want to determine the resonant frequency. Basically i can determine the resonant frequency base on the dimensions. But i need to proved it using experimental set-up. So i applied AC Voltage to the material then the material...
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    Vibrational frequency of Piezoelectric effect

    when a piezoelectric material experience a stress it generates voltage, and also when you applied voltage the piezo-material experience a vibrational frequency. Using oscilloscope we can determine the induced frequency of the piezo-material with respect to the applied voltage. Now given the...
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    Determine the shear strain

    I don't know how to solve this kind of problem: Given a crystal and its volume V. This Crystal is subjected to a shear stress making a slip plane (h k l ) in a slip direction [h k l]. Given also the lattice parameter a and slip plane spacing L, and the edge dislocation a/2 that passed halfway...
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    What is the stress of the rotated axis

    Given only the triaxial stresses: ax = 10 MPa (along [100]), ay = 10 MPa (along [010]), and ax = -30 MPa (along [001]), what is now the components of stresses in rotated axis? so based on the equation aT = [L][a][LT] let aT the components of stress of rotated axis, L the direction cosine, LT...
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    Effective annealing parameters in N-doped Zinc oxide

    Good day every one! Based on my research as you increased the temperature, the grain size become bigger and the thickness decreased, but in some paper, thickness increased. The effects of annealing temperature is almost the same to the temperature. But if you will considering doping for...
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    What is the best for piezoelectric material?

    Based on my research the effects of the holes, electrons, acceptor and donor concentration is telling you the direction of the polarization and the conventional sign of the electric potential generated. But up until now, i don't know what is the best material to used for piezoelectric material...
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    Relationship of bulk modulus and fractional volume change

    So my question is, if the bulk modulus change by 5%, what is the fractional volume change value? is it times 0.05 or divided by 0.05? or the fractional volume change still the same?
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    Work done up to fracture

    Good day everyone! i have a problem dealing with the fracture analysis. We all know that the work done per unit volume is equal to the area under the curve of stress-strain curve or we can express it in terms of integral form, and if we're looking at necking point stress can be express in this...
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    Difference between ohmic contact and schottky contact

    Hi guys!, i want to know the advantages/disadvantages of using ohmic contact and schottky contact, because i will fabricate a photodiode (p-n junction) and lot of the articles say that ohmic contact is the best for this kind of device. But schottky contact rectify the signal which is more...
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    How dopant enhances the superconductivity of BSCCO

    Good day! i really need your help, I want to know the effect of Dopant (for Example Manganese) in BSCCO (for example Bi-2212) on it's Resistivity? i read some articles saying it increases the critical temperature of the superconductor, But it didn't explain why, and how is that related to the...
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    Role of Mn in Magnetoresistance of Perovskite

    Good Day everyone! right now i'm searching for possible research in magnetoresistance properties of perovskite. So far, i already know the effect of Mn in Perovskite, it enhance the ferromagnetic properties of the material. And Manganites in Ferromagnetic State possessed magnetoresistance in...
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    Heating a Lanthanum Hydroxide

    Hey guys!, I just want to know what will happen when you heat up lanthanum hydroxide La(OH)3 from 20 degree Celsius to 900 degree Celsius in a furnace with O2 gas. Is the mas of La(OH)3 increases? and why? thanks in advance!
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    Factors affecting the size of ZnO thin films (by spray pyrolysis)

    Good day guys, aside solution concentration and depositing time, what are the factors affecting the size of the ZnO thin films deposited by spray pyrolysis. Also please include the articles or links for citation thanks!
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    Role of Bias Voltage in Semiconductor Light detector

    Good day!, today, i visited an Institute about Semiconductor devices, One characterization device (Reflectance Spectrometer) which used to determine the reflectance of the semiconductor materials. This device used Semiconductor detector to detect the reflected light from the sample, but i'm...
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    Criteria for choosing a substrate for thin films

    Hi guys!, i want to know what are the criteria in choosing a substrate to deposit thin films, like what are the physical and chemical properties of the substrate to be compatible in depositing thin films?
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    Silicon wafer as substrate in Zinc oxide thin films

    Good day, many articles used sillicon wafer as substrate over others (like:platinum, glass, sapphire and etc) to grow Zinc oxide thin films, but i'm don't know the real reason they choose silicon wafer as substrate compare to others. so i'm asking what are the advantages of using Silicon wafers...
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    Combining p-type and n-type semiconductor materials

    Hi Guys, i want to fabricate semiconductor p-type and n-type material and i want it to combine to make a p-n junction diode, but i don't know how to combine or merge the two, (my materials are thin films) i'm thinking to solder it but i'm afraid that it will break, or distort, or i'm thinking to...
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    Determine the lattice parameter of Tetragonal system

    As a part of our exercise we need to determine the lattice parameter of the given xrd peaks (http://bama.ua.edu/~mweaver/courses/MTE481/Lab2_PP.pdf [Broken]. the last page of the link), heres the peak data: 2theta 23.73 39.23 46.36 56.69 62.31 71.1 76.15 84.35 89.2 97.29 102.21 110.83 115.9...
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    Role of TiO2 in Gas sensor Device

    Good day, TiO2 have many possible application in material science, one of this is in Memory device, base on some literature TiO2 had a good chemical stability at high temp, so this is one reason why TiO2 is best candidate for this application, but beside of that, what other properties of TiO2...
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    Overall rate of reactions of decomposition of dimethyl ether

    Hi Guys, i'm solving this for almost a week, this is a part of our probset in chemical kinetics: The thermal decomposition of dimethyl ether: CH3OCH3 ---K1--> CH3' + OCH3' CH3' + CH3OCH3 ---K2--> CH4 + CH2OCH3' CH2OCH3' + --k3---> CH3' + HCHO CH3' + CH2OCH3' ---k4--> C2H5OCH3 using steady-state...
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    Basis Atom of Superconductor

    Hi everyone, I'm trying to simulated the XRD pattern of Bi2Sr2Ca2Cu3O10, but i'm having a problem of finding the basis of atom(and their respective position). Also its JCPDS is quite hard to find, so if anyone working with this, may you provide a link or articles about my problem. Thanks...
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    Determine the intensities of GaAs crystal planes

    GaAs crystal structures have basis atoms: Ga: (0 0 0), (0.5 0.5 0),(0.5 0 0.5),(0 0.5 0.5) As: (0.25 0.25 0.25),(0.75 0.75 0.25),(0.75 0.25 0.75),(0.25 0.75 0.75) i'm trying to find intensities at all of its plane, using this equation: I = (F^2)*m*Lf (m= multiplicity, Lf=lorentz factor)...
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    Calculation of Intensity of of AX crystals

    I'm still confuse on using the equation about atomic scattering factor, f = a*e^(-b+((sin(theta)/lamda)^2) + c (general equation), where sin(theta)/lamda = 1/2d = 1/(2*(sqrt(a^2/(h^2 + k^2 +l^2)))), so this term is dependent on the plane. which you will used to find the Intensity of crystals...
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    Determine Crystal structure of non-cubic crystal in XRD plot

    Given only 2theta and intensity, how to know the crystal structure (except cubic) of non cubic crystals, and also determine their lattice parametera,b,and c, if there's a link or website discussing techniques to determine crystal structure of all crystals, please don't hesitate to put it here...
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    Rules in determining family of planes in Hexagonal

    Hi guys, i'm assume that you already know the 7 crystal system, each crystals have unique way of determining the family of planes, for example in cubic, we all know (111) plane is same (-1-1-1), and so on ((-1-11),(-11-1)...) a total of 8, in fact there is pattern to determine how many possible...
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    Specific heat Capacities of metals

    Hi Admin, please allow me to post this here: The General Formula for Specific Heat Capacity is: C(Total) = C(electron)+C(phonon) C(electron) = aT where a is the sommerfield constant. C(phonon) = bT^3 this time i don't know what is b (some constant) so my problem is, how can i determine b...
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    Reducing a mathematical expression

    Hi guys i need your help! How can i reduce this equation: (Nd-Na)*[B*sqrt((Nd-Na)^2) + n^2) - sqrt((Na-Nd)^2) + n^2)] into this: (B-1)*(Nd-Na) + (B+1)*sqrt(Nd-Na)^2) + n^2)? I'm totally depressed, i'm always stocked in sqrt part of the equation: if there's a techniques in dealing this kind...
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    Band Gap of Semiconductor Materials

    Hi Guys, i need your help, where can i download free articles about the band gap of semiconductor materials (like copper (II) oxide). don't mention sciencedirect and arxiv, because i already explore that, and they provide limited research articles. thank you.
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    Metallic Superconductors

    Hi Guys, Please give me an example or list of Metallic superconductors (new metallic superconductors (year 2010-2014). thanks :).
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