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Question 9: a) The contrast transfer function, H, can someti…

Question 9: a) The contrast transfer function, H, can sometimes be written as a product of two terms: H(u)=E(u)B(u) Within the weak phase object approximation, the B(u) term can be simplified to B(u)=exp(iχ(u))∼sin χ(u) and E(u) is referred to as the envelope function. Which lens is most closely associated with the contrast transfer function what lens parameters are the most important? (2) Discuss the factors that contribute to E(u). (2) b) You make measurements of the contrast transfer function of a TEM operating at 300 kV.  The contrast transfer function measured at 3 different defocus values are shown below.  The orange curve is the envelop function and the gray curve is the contrast transfer function. You are interested in studying a sample with important Miller plane spacings of 2.3 and 1.9Å.   Explain the advantages and disadvantages of using each of the three imaging condition to investigate your sample.  Which condition is best and why?  (4) Estimate the spherical aberration coefficient.  (2)

Question 11:  a. With a real space schematic of Miller plane…

Question 11:  a. With a real space schematic of Miller planes near an edge dislocation, explain and illustrate how changes in the diffracting condition enable a dislocation core to be located with weak-beam dark-field imaging.                                                                                    (3) b. A face center cubic (lattice parameter 0.45 nm) is put into a microscope operating at 300kV and the crystal tilted into the [011] projection.  You index the diffraction pattern as shown below.  The material may possess partial dislocations with Burgers vectors [11-2]/6, [1-21]/6 and [-211]/6.  By slightly tilting you can set up 2-beam conditions to perform g.b analysis. By considering the 4 reflections nearest the direct beam, determine if you are able to differentiate these three dislocations.                                                                                                   (4) c. You then image the dislocations using weak beam dark-field imaging with the (-11-1) beam. Estimate the value of excitation error for g-2g and g-5g conditions.                               (3)

Zara Owner Inditex’s Sales Grow as It Holds Off on Major Pri…

Zara Owner Inditex’s Sales Grow as It Holds Off on Major Price Hikes – WSJ 11 01 2024.pdf Based SOLELY on the article above (ABSOLUTELY NOTHING FROM THE INTERNET – IF SO, THE WHOLE QUESTION WILL BE GRADED ZERO!): In a SWOT analysis approach (without using the 4 quadrants), please mention 3 Strengths, 1 Weakness, 3 Opportunities, and 1 Threat – ONLY based on the content within the article. REMEMBER: Strengths and Weaknesses are meant to be INTERNAL; whereas Opportunities and Threats are meant to be EXTERNAL! Avoid repeating the same strength or weakness, etc., in different words or sections from the article. So 8 answers in total. 1.5 points each. Strengths: 1. 2. 3. Weaknesses: 1. Opportunities: 1. 2. Threats: 1. 2.