Writing the Discussion Section

A Discussion section should be as satisfying to read as the last chapter of a mystery novel. The groundwork is laid in the Introduction section, technological tools are described in the Methods section, evidence is revealed in the Results section, but it is in the Discussion section where the mystery is solved. 

This chapter focuses on the Discussion section, the iast part of the standard IMRD structure for a journai articie. The Discussion section, as mentioned in chapter 4, can stand aione or can be part of a combined Resuits and Discussion (R D) section. in either case, it serves the same major purpose to interpret the results of the study. In this chapter, we analyze excerpts from various Discussion sections, including those that accompany results presented in chapter 4 (excerpts 4B-4G). Upon completion of this chapter, you should be able to do the following  

As you work through this chapter, you will write a Discussion section for your own paper. The Writing on Your Own tasks throughout the chapter will guide you step by step as you do the following  

Words that soften interpretations and suggest that interpretations are not absoiute facts. Common hedges in scientific papers inciude the foiiowing  

To begin the analysis of the Discussion section, we ask you to read and analyze the Discussion section from the article on the analysis of aldehydes in beer. 

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Despite the frequency with which combined R D sections now appear in the chemical literature, we have chosen to address the sections separately in this textbook. The different purposes of Results and Discussion sections are important to understand and distinguish, even if you ultimately choose to write a combined R D section. In this chapter, we focus on the Results section. The Discussion section and the integrated R D approach are examined in chapter 5. 

Read and review the Discussion sections of the journal articles that you collected during your literature search (begun with Writing on Your Own task 2C). Read these Discussion sections to learn more about your topic and to find ways to describe and interpret your findings. Examine how the authors applied their findings to a broader research context. Identify articles that you want to cite in your paper, such as works that offer supporting or conflicting evidence. Jot down careful notes as you read. 

The first move is reiterated as needed for multiple sets of results, ideally paralleling the order that was used in the Results section. As in the Results section, you can use subheadings to help the reader locate the discussion for each result. If, while writing the discussion, you question the logic of your sequencing, you need to revise both the Results and Discussion sections to align them. 

With the audience, purpose, and organization of the Discussion section in mind, we are ready to analyze excerpts of Discussion sections from the chemistry literature. We begin by analyzing the excerpts move by move and then examine a few writing conventions common to the entire section. 

Part 2 Analyzing Writing across the Discussion Section... 

Here, we examine writing conventions that are common throughout the Discussion section. We focus on tense and voice in addition to two word-choice issues, the use of we and hedging words. 

Reflect on what you have learned about writing a Discussion section for a journal article. Select one of the reflection questions below and write a thoughtful and thorough response ... 

Using parts 2 and 3 of the Peer Review Memo on the Write Like a Chemist Web site, review the Discussion section below. We have included the last paragraph from the Introduction section to help you better understand the Discussion. You do not need to review the Introduction. Provide specihc suggestions that your classmate can use to improve the Discussion section. (The Discussion section below is adapted from an original source, noted in the Instructor s Answer Key.) [Excerpt from the Introduction]... 

We note at the outset that this chapter deals specifically with the electrochemistry of CPs per se electrochemistry and mechanisms associated with polymerization processes are discussed in the next chapter. It is also noted that it has been attempted to write the first section (4.1) specifically for readers with little knowledge of electrochemistry and no familiarity with electrochemistry of CPs. 

Maintenance costs account for a large fraction of the total operating expenditure (opex) of a project. Because of the bath tub curve mentioned above, maintenance costs typically increase as the facilities age just when the production and hence revenues enter into decline. The measurement and control of opex often becomes a key issue during the producing lifetime of the field as discussed in Section 14.0. However, the problem should be anticipated when writing the FDP. 

In writing Eq. (8.41), we have clearly treated Aw as a contribution to enthalpy. This means we neglect volume changes (AHp jj. versus AUp jj.) and entropy changes beyond the configurational changes discussed in the last section (AGp jj. versus AH jj.). In a subsequent development it is... 

In this section we derive a nonpenetration condition between crack faces for inclined cracks in plates and discuss the equilibrium problem. As it turns out, the nonpenetration condition for inclined cracks is of nonlocal character. This means that by writing the condition at a fixed point we have to take into account the displacement values both at the point and at the other point chosen at the opposite crack face. As a corollary of this fact, the equilibrium equations hold only in a domain located outside the crack surface projection on the mid-surface of the plate. This section follows the papers (Khludnev, 1997b Kovtunenko et ah, 1998). 

The units of AG are joules (or kilojoules), with a value that depends not only on E, but also on the amount n (in moles) of electrons transferred in the reaction. Thus, in reaction A, n = 2 mol. As in the discussion of the relation between Gibbs free energy and equilibrium constants (Section 9.3), we shall sometimes need to use this relation in its molar form, with n interpreted as a pure number (its value with the unit mol struck out). Then we write... 

A78. M. J. Udy, ed., Chromium, ACS Monograph No. 132. Reinhold, New York, 1956. Volume 1 Chemistry of chromium and its compounds. Chapter 6, M. C. Udy The physical and chemical properties of compounds of chromium. The last section, pp. 240-246, organometallic chromium compounds, is almost entirely concerned with a discussion of polyphenylchromium compounds, at the time of writing not recognized as bis-7r-arenechromium derivatives. 

Once again, we emphasize that the order of reaction and the value of the rate constant must be determined by doing experiments. Knowing the order of reaction then makes it possible to write the specific rate law for the chemical process. In the next three sections, we discuss how chemists determine orders of reactions and further explore how rate laws are related to chemical mechanisms. 

Using a unnormalized n-electron Slater determinant D(j) as system wavefunction, constructed as discussed in section 5.1, then one can write the n-th order density function p " (j) as ... 

We now single out one of these interactions for our discussion of the integer-spin 5 = 2 system, and we defer an explanation of this deliberate choice to the end of this section. We write the spin Hamiltonian for an isolated system (i.e., no interactions between paramagnets) with 5 = 2 and 7=0 (i.e., no hyperfine interactions) as... 

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