Explain why the same surface roughness values do not necessarily represent the same type of surface. Please give some examples. Hint: surfaces that have the same Ra values, may be are very different geometrically and have different tribological performance. Give examples.
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Cubic boron nitride is used as an abrasive in machining steel as an alternative to diamond, whereas hexagonal boron nitride is frequently used as a lubricant in electronic and high-temperature applications. Explain how these different properties result from different crystal structures and bonding in this material. (Hint: think about the different crystal structures of carbon!)
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Describe examples of how different methods of dating events and rocks were used to reconstruct the geologic history of the Grand Canyon; and illustrate why the canyon does not represent all of geologic time.
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Give 2 examples of how to determine a thermodynamic properties (H, S, G, etc) of a substance by using the thermodynamic diagrams (PH Diagram, TS Diagram and Mollier Diagram).
Give 2 examples of how to determine a thermodynamic properties (H, S, G, etc) of a substance by using the tables of thermodynamic properties.
Each example must be different from each other
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Describe the specific properties of the surface of the Moon, and how they got there. Be specific, using descriptions as though you were speaking to a friend who doesn't know anything about the subject.
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How do detrital sedimentary rocks differ from chemical sedimentary rocks? Explain how the soil pedon contains all aspects of mechanical and chemical weathering leading to sedimentary rock formation (include all of the different layers and the different types of rocks they would represent if exposed to the surface).
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In engineering economic (chemical engineer) evaluation, what's the definition for these terms?
Extended credit
In process inventory
Product inventory
Please explain using language that can be understood by laymen, preferably adding day to day analogies.
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1. Truth or false
Risk assessment involves (1) hazard identification or evaluation, (2) dose-repsonse evaluation, (3) exposure evaluation, and (4) risk characterization.
Exposure routes include respiration, dermal contact, and oral intake.
Volatility and bioconcentration quickly reduce a substance’s availability, while dissolution and adsorption often prolong it.
Contact frequency is not related to exposure at all.
Approximately 50% of our population is exposed to toxic chemicals.
Uncertainty is an uncommon feature of risk characterization.
Assessment of ecological risk follows different steps as that for humans.
Risk assessment involves dose-response extrapolations.
Metabolism and disposition of drugs often are not related to physiological time and development.
Ecosystems possess energy and material flows, biogeochemical cycling, nutrient retention and an ability to resist changes and detoxify pollutants.
Risk management considers only risk, but not benefits.
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Petroleum Engineering:
How can the knowledge of grain size distribution aid in the
evaluation of a petroleum reservoir?
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Discuss ways in which the constraints on possible solutions to an engineering design problem arise.
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What are the disadvantages of polymers? What is an electrical property of a polymer and is there any exception to that electrical property? if so, what is it?
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