Reviewing the Technical Literature

1. Reviewing the Technical Literature Brian Paul

2. Gathering Evidence • Keyword searches • Google Scholar • ISI Web of Knowledge • Be sure to evaluate whether the keword database covers the key journals in your field • Keyword searching is iterative • Kewords become more refined over time • Closure • Use citations to find new related papers • When no new papers are found, you have closure

3. Key Features of a Synthesis • It accurately reports information from the sources using different phrases and sentences; • It is organized in such a way that readers can immediately see where the information from the sources overlap; • It makes sense of the sources and helps the reader understand them in greater depth.

4. Different types of syntheses • Background and Relevance • Purpose is to establish context and relevance • What is a relevant research question/problem? • Thesis-driven • Purpose is to establish uniqueness • What is a novel thesis (answer/solution)? • Where are the technical gaps in other theses? • How does the evidence support or deny your thesis?

5. Background • Purpose: to help reader understand context of research • EX: Diffusion bonding of microreactors • What are microreactors? • Microchannels accelerated heat & mass transfer • Increase cross-section of flow by using arrays • Why are microreactors important? • Less time required in the channel  short channel lengths  miniaturization  distributed and portable processing • Faster heating and mixing  better process control  more precise chemical processing

6. Relevance • Purpose: to establish a relevant question/problem • EX: Diffusion bonding of microreactors • Channel warpage is caused during the diffusion bonding of microchannel heat exchangers (MCHX) • Channel warpage can lead to flow maldistribution within the MCHX • Flow maldistribution reduces the effectiveness of MCHX requiring more surface area • More surface area requires the device to be larger • THEREFORE: Channel warpage must be minimized to enable miniaturization • OUTCOME: What causes channel warpage during diffusion bonding?

7. Research Questions • Questions are typically iterative • Why do we miniaturize? (distributed processing) • How do we miniaturize? (chem etch and diff bonding) • What causes channel warpage during diffusion bonding? (nonuniform stress distribution) • What caused channel warpage in a particular diffusion bonding cycle? (thermal warpage?) A B

8. Thesis-driven • Purpose • Show readers that you are familiar with the field and are thus qualified to offer your own opinions • Where are the technical gaps? • Must start with a question • How can we create flow field uniformity within microchannels? • What causes channel warpage during diffusion bonding? • What caused channel warpage in a particular diffusion bonding cycle?

9. Read and Evaluate Each Paper • What does this paper say about my focus? • Gaucho et al.1 found that header cross-sections must be 10X channel cross-sections in order to ensure the uniform distribution of flow. • What is the thesis, purpose or context of the source? What are the limitations of the paper? • In evaluating the distribution of cooling fluids within rocket engines, Gaucho et al. … • Is the source credible? • All claims were based on CFD simulations. No empirical evidence was provided to validate findings. OR • Trial and error methods were used to establish this principle. OR • A full factorial design of experiments was developed based on header diameter and channel diameter. • What questions remain (relevance)? What approaches have not been taken (thesis)? • What did you learn from this paper that is important for the reader to know?

10. Organizing the Body of Your Synthesis • This is the value add • Group the literature together around common themes based on your evaluations (see prior slide) • Requires some thought i.e. this could take a while • How can you bring structure to the literature that has been published? • Chronology • Classification – what are the patterns you see • Diffusion brazing • Conventional brazing compounds • Electroplated phosphates • Nanopowders • …

11. Each Synthesis Paragraph … • Begins with a topic sentence. • Includes information from more than one source. • Clearly indicates which material comes from which source using lead in phrases and in-text citations.  • Beware of accidental plagiarism which most often occurs when students are synthesizing sources and do not indicate where the synthesis ends and their own comments begin or vice verse. • Shows the similarities or differences between the different sources in ways that make the paper as informative as possible. Should include paper summaries and evaluations. • Represents the texts fairly--even if that seems to weaken the paper! You are simply repeating what the source says … • in fewer words • in your own words

12. Synthesis Summary • Remind readers of the most significant themes you have found. • Key concept in creating uniform flow fields is to produce the same pressure drop through all pathways in the device. • Offer an interpretation of the material and/or take a position.  • No uniform flow field micromixers currently exist in the literature. • You may also want to suggest further research or comment on things that it was not possible for you to discuss in the paper. • This paper will discuss the design, fabrication and testing of a uniform flow field micromixer to be used for the production of nanoparticles.

13. Assignment #3 • Due Monday, April 27 • Synthesis paper – 4 to 6 double space pages • 5-7 minute presentation – alphabetical order • See synthesis paper details in syllabus • Perform keyword searches – at least 20 papers • Evaluate each paper • Short summary of what it is about (sentence or two) • What did you learn that the reader should know i.e. that shapes your research question or thesis? • Write synthesis • Expected outline (write like it is the front of a manuscript) • Upfront paragraph(s) provide the context for the lit review • Organize literature into paragraphs (see organization slide) • Summary • If background  Why is your topic important? • If relevance  What is a relevant research question? • If thesis-drive  What are the technical gaps? What is your thesis?