1.6 What is the activity of 1 gm of 235U in [Ci] and in [Bq]? Do the same for 232Pu.

It is desired to study the first excited state of oxygen, which is at an energy of 6.049 MeV. (a) Using the (a, n) reaction on a target of ¹³C, what is the minimum energy of incident alphas which will populate the excited state? (b) In what direction will the resulting neutrons travel? (c) If it is desired to detect the neutrons at 90° to the incident beam, what is the minimum a energy that can result in the excited state being populated?

6) Welcome to Mars! After a glowing review by your ME461 Instructor, you are the chief nuclear refueling engineer at the Londres Nova Nuclear Power Station on Mars. This power station consists of 3 Fissionator-class nuclear power plants, each producing 3000MW. a) What is the minimum amount of U-235 will you need to order from the Ceres Uranium Corporation to keep these reactors running for two years? (Assume complete burnup) b) The Phobos Plutonium Production Plant is interested in selling you Pu fuel. Since Fissionator-class reactors can also run off of Pu-239, calculate how much plutonium it would take to keep them running the same amount of time. (hint: this will require finding a new value in table 3.4 for your equation)/n7) Due to your excellent work on the previous refueling outage (the reactor hasn't melted yet!), the nearby Mariner Valley Nuclear Power Station has requested some assistance. They would like you to calculate the macroscopic neutron absorption cross section of a proposed UO2 fuel loading that they're considering. Assume 7 w/o enriched uranium. Their reactor operates at a fuel temperature of 600 deg C (i.e., Assume non 1/v behavior).

1. Calculate the total binding energy and the binding energy per nucleon of (a) 7Be and (b) 56Fe. An isotope of fission is 1515m, with a half-life of 90 y. How long will it take 0.05 g to decay to 0.01 g? 5. Assume that a source of 60Co can be safely managed if it contains less than 0.01 Ci. How long would it take for a source containing 5 Ci of 60Co to reach this value? 6. Write the following in equation form to show the balance of atomic and mass number and the compound nucleus: (a) 'Li(p, a), (b) Be(d, p), (c) 'Be(p, a), and (d) ºBe(d, a). 9. 10 mCi of 90Sr is separated from a fission product mixture and allowed to sit for 90y to grow in. What is the activity of 90Y at (a) 20 h and (b) 600 h?

2.1 First, watch the first two parts of The Real Chernobyl on YouTube. This is a mostly a human-interest documentary about the people involved with the aftermath of the Chernobyl accident. Next, read the "Chernobyl Appendix 1: Sequence of Events," available on Canvas. In the space below, provide a three- paragraph summary of the Chernobyl accident, including the main causes, resulting damage, lasting impacts, and lessons learned.

1.6 What is the activity of 1 gm of 235U in [Ci] and in [Bq]? Do the same for 232Pu. 94 1.7 What is the time required for 238U to decay by 1%? 1.8 The nuclide Po emits either an alpha particle or a beta particle with a half-life of 3.10 min. a) Write equations for each reaction. b) Calculate the decay constant for these reactions. c) Determine the number of atoms in a sample if it has an activity of 100 μCi. d) Calculate the activity after 1, and 2 half-lives in [Ci] 1.9 The reaction and decay equations for conversion of 232U to 232 Pu are shown below. 94 232U + n → ²32U+Y 92 232U233Np +_iß 233Np 23 Pu+_iß 93 (Note the notation for ß decay in the equations.) What is the total energy given off in these reactions? [MeV]

1. A core consists of 157 fuel assemblies, each fuel assembly forming a square-lattice 17x17 array. In each assembly, 24 locations of that lattice are reserved for control assembly rodlets, and additionally, the central location is reserved for instrumentation. The remaining locations contain fuel rods. Fuel rods are formed by UO2 fuel pellets clad in Zr-based cladding. The outside cladding diameter is 0.374", the clad thickness is 0.0225", and the diametral gap is 0.0065". (This is the gap between the clad and pellet; note that the diametral gap is twice the radial gap.) Axially, the fuel pellet stack (so-called active core) is 14 feet tall. Pellets are made of UO2 sintered to 95.5% of its theoretical density which is 10.96 g/cm3. Dishing and chamfering amount to 1% of the pellet volume. Assume that fuel enrichment is 4 wt%. The thermal power of AP 1000 is 3,400 MW-th. a. Calculate the total heavy metal loading, i.e., the total uranium weight in the cycle 1 fresh core. [Justify all assumptions.] b. Calculate specific power expressed in W/gU. Also, calculate specific power expressed in MW/tU. c. Assume that the reactor has an annual refueling cycle composed of 15 days of shutdown for refueling, and the remaining -11.5 months of operation at power. Further assume that the average capacity factor, when operating at power, is 98%. What is the average burnup that fuel receives each year? You may express burnup in MWd/tU or GWd/tU or MWd/kgU. [Note that "t" will always denote metric tons, i.e., 1,000 kg, unless very specifically stated otherwise. Also, U in burnup units refers to the initial mass of uranium (ALL uranium, not just U235).

6. A narrow beam of 10,000 photons per second is normally incident on a 6 mm aluminum sheet. The beam consists of equal numbers of 200 keV photons and 2 MeV photons. (a) Calculate the number of photons per second of each energy that are transmitted without interaction through the sheet. (b) How much energy is removed from the beam per second by the sheet? (c) How much energy is absorbed in the sheet per second? 7. A source of 1 MeV gamma rays produces a uniform flux of 106 photons/cm²*s at a distance of 150 cm. (a) What is the absorbed dose rate at that distance? (b) What is the absorbed dose rate at 2 m? 8. A planar disk source with a diameter of 200 cm emits 662 keV gamma rays with strength (SA) of 107 y/cm²*s. What is the dose rate to air at a point 5 cm over the centerline of the disk? 9. A 2 Ci ¹37 Cs point source is placed at the center of a spherical (R=10 cm) lead shield. Calculate the photon flux 50 cm away from the point source, considering photon attenuation in air./n10. What thickness of lead is required to attenuate a broad beam of 500 keV photons to one half of the original number? Be sure to use appropriate buildup factors!