Problem Set

What has caused the breakthrough in early 1990s in developing the first miniaturized liquid separation chip since the GC chip was first reported in 1979 (2 marks) 

Name three kinds of glass substrates commonly used to fabricate microchips. Describe the process of photolithography used in glass micromachining. (5 marks) 

What is the difference between a photomask and an etch mask in glass micromachining (2 marks) 

Compare and contrast positive and negative photoresists. (4 marks) 

Describe the use of NH4F in the wet HF etch process for glass micromachining. (2 marks) 

Demonstrate that the extended planar zigzag conformation of crystalline polyethylene is not permitted in crystalline polytetrafluoroethylene. 

In the planar zigzag conformation of polyethylene (see Fig. 2.2) the centers of the substituents (hydrogen atoms) of alternate carbons will be separated 

For a single crystal of polyethylene of thickness 12 nm, estimate the number of monomer units in each section of chain in the extended zigzag conformation as well as the number of folds of a chain of molecular weight M = 10 g/mol. 

Each monomer unit, — CH2—CH2 —, occupies a length of extended chain given by 

Therefore, there are 12/0.255 = 47 monomer units in each section. 

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The derivation of equation 7.31 is considered in problem 33 in the end-of-chapter problem set. 

Because exceeds the confidence interval s upper limit of 0.346, there is reason to believe that a 2 factorial design and a first-order empirical model are inappropriate for this system. A complete empirical model for this system is presented in problem 10 in the end-of-chapter problem set. 

This book, for the most part, is a stand-alone text. It addresses not only the fundamentals of PSA as a science, but insights on the regulatory framework affecting its development and apidication. In particular, it provides the basic methods of analysis that can be employed, available databases, an excellent set of examples, software resources, chapter summaries that tacilitate comprehension, and problem sets that are very well connected to the theory. While much has been written about probabilistic safety assessment over the last three decades, this is the most comprehensive attempt so far to provide a much needed college level textbook for the education of risk and safety professionals. It also provides a valuable reference for any individual curious enough about the risk and safety sciences to want to become much more informed. 

The actual invariants in invariant properties of a lamina include not only U., U4, and U5 because they are the constant terms in Equation (2.93) but functions related to U-), U4, and U5 as shown in Problem Set 2.7. The terms U2 and U3 are not invariants. The only invariants of an orthotropic lamina can be shown to be... 

I have come to expect my students to interpret or transform the sometimes highly abbreviated, and thus relatively uninformative, problem set statements at the end of each section such as derive Equation (3.86) to the more formal, descriptive, and revealing form ... 

ThomsonUOW Click Organic Interactive to practice naming alkenes in this interactive problem set. 

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