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4versionb. Analyzing Polymers -PC12 Below is a DSC thermogram of polyethylene-like polycarbonates with varying amounts of methylene in their polymer sequence (where n=2,4,6,8, or 10) according to the general structure also shown below. Note that no glass transition temperature is indicated on the thermogram for any of the polymers.  A. (.4 pt) What is the Tc for the polymer PC12? B. (.4 pt) What is the Tm for the polymer PC12? C. (.6 pts) Which polymer has the highest percent crystallinity and briefly describe why? D. (.6 pts) Which polymer would be more susceptible to creep and briefly describe why?       The same polymers were also analyzed with XRD and compared to high-density polyethylene (HDPE) E. (0.5 pts) Based on these results, which polymers have crystal structures similar to HDPE and which likely have different crystal structures? F. (0.5 pts) The plane indicated around 2Ɵ=21° has a miller indices of (110). Draw the plane.  G. (1 pts) You’ve determined your % crystallinity for your PC12 sample is 62% and has a density of 140,000 g/cm3.  Calculate the density of the density of completely amorphous PC12 if the density of completely crystalline PC12 is 190,000 g/cm3? Show all work H. (0.5 pts) You decided to run gel filtration chromatography (a form of size-exclusion chromatography) on your PC samples, but you forgot to label your samples. Which of your PC samples do you think corresponds to the lightest gray (furthest to the right) in your GPC plot and why? 

3. Metal crystal structures consist of lattice patterns that can be broken down to the smallest repetitive volume, known as a unit cell. We have discussed three types of cubic structures, simple cubic (SC), body centered cubic (BCC), and face centered cubic (FCC) structures. Answer the following questions below:  A. (0.5pts) Sketch a SC structure AND a FCC structure B. (1pts) Calculate the number of atoms per cell AND atomic packing factor for SC AND FCC (MUST state/illustrate how to determine parameters for both structures – show work/thought process). C. (0.5pts) For a metal that consists of a FCC structure, describe one plane in detail that is susceptible to slip/deformation. Responses can include sketches if it helps convey your thought process – responses that include a sketch must explain the main concept of why this plane is susceptible to slip/deformation.  

1. Your company standards mandate that the polydispersity index for your new polymer processing procedure yield a polydispersity index of less than or equal to 1.15. Your polymer processing ends with 3 fractions, labeled D, E, & F in the table below with the breakdown of different size chains within your new polymer sample. Does your new fabrication method meet that standard? Show all your work and justify your answer (describe the measurement you are comparing and why).    Fraction MW # of Chains Ni*Mi Ni*Mi^2 D 75 25 1875 140625 E 140 100 14000 1960000 F 250 120 30000 7500000 SUM: 465 245 45875 9600625

Which practice is most associated with supplier risk management?

Choose the pathology that is misspelled below:

Write down 2 symptoms of Abdominal Aortic Aneurysm (AAA).

Write down the name of 2 vessels that arise anteriorly from the aorta.

Write down 3 risk factors/causes of abdominal aortic aneurysm (AAA) that were discussed in the lecture.

A 72-year-old patient with a history of congestive heart failure is admitted with shortness of breath. On exam, you note dyspnea when lying flat, bilateral pedal edema, and jugular venous distention. Which of the following is the most likely underlying cause of these findings?

A disease process causing consolidation, that results in increased lung density will result in which of the following? I. increased tactile fremitus II. dull percussion note III. decreased thoracic expansion IV. decreased WOB I, II, III I, III, IV II, III, IV I, II, III, IV