Hypothesis: Changing the %NaCl in swelling solution will affect dye release and swelling ratio.Experimental Design: 4 groups (DI water, 10% NaCl, 20% NaCl, and 30% NaCl) with 5 replicates*Please note that maximum solubility of NaCl in water is ~37%. We adjusted the % accordingly.*Introduction
The purpose of the introduction is to set up your experiment contextually and logically. The bulk of your
3+ citations should be here. There are 3 general sections to the introduction: establish background, identify
problem, propose hypothesis. In doing this, you should introduce all of the major concepts / materials that
youll be working with, and provide a logical progression from your identification of the problem to your
hypothesis.
The introduction should include background information that places the study in CONTEXT.
o What topic / materials are we talking about?
o How is this topic important for the field as a whole?
o How does our research expand on research that has been done previously on related topics?
o Answering these questions should tell the reader why our hypothesis is important.
Remain scientific. Present previous work, and stick to pointing out gaps in that work when
formulating your problem statement.
o Do not delve into politics surrounding the field of research, except in the broadest terms to
highlight a need (this is still not recommended though).
o If you do talk about areas of public debate, do not choose sides and do not point fingers.
Use peer-reviewed literature for your citations.
o Review papers are acceptable for concepts, but make sure not to attribute findings to them.
o Avoid editorials, even those from scientific journals. These do not undergo the same vetting
as actual journal articles, so should be approached as opinion pieces. Youre better off going
through their citations to get information more directly.
o Do NOT cite handouts you were given in class, as researchers anywhere else would not have
access to these materials. You may cite the original source.
Dont surprise the reader with an unjustifiably specific hypothesis.
o Specific hypotheses are good, but make sure that you include all necessary logic to support
it.Material & Methods
Your goal in this section is to describe how you carried out the experiment. Exact structure of this section
will change based on the experiment, but it is usually helpful to have 1 section on sample preparation and
separate sections on each experiment (if there is more than 1). If you have multiple experiments, it is often
helpful to start with a short paragraph giving an overview of the entire project.
Treat your reader like a competent researcher.
o Common materials like pipettes, scales, spatulas, and fume hoods are not necessary to
mention.
o It is assumed that if a researcher needs to measure something, they will use the proper tools
and follow any necessary safety precautions.
Experimental Setup!
o If you have multiple experiments, be very clear about which one you are describing.
o Establish what your experimental groups and replicates were before you jump into
experimental details.
o Do NOT include a list of all materials used. These should be included organically as you
describe how your conducted the experiment.
o Control Groups are different than Controlled Variables.
Controlled Variables are things that could affect the experiment that we keep
constant: temperature, curing time, lighting, air flow, etc. The assumption is that you
control environmental variables between experimental group, so you do not have to
list these unless they are of particular importance.
Control Groups are samples that we test, already knowing how they should turn out.
They are the things you compare your experiment against to see if you have a
significant effect and/or if you experiment is working at all (depending on the
experiment). These are very important for verifying that youre actually testing what
you think you are testing.
Experimental Methods!
o Include all relevant information for someone who would want to reproduce the experiment.
o Include the finicky details of an experiment, such as the volumes, masses, sizes, times, etc.
o Use specific numbers (24hrs) rather than vague terms (overnight) whenever possible.
o Use proper terms. If equipment or a technique has a name, use it.
o Include all relevant equations.
Define all variables in all equations.
Equations should be referenced explicitly in the text: eg. Using equations 1 and 2 we
calculated
Statistics!
o Choose the appropriate test for your hypothesis.
Remember that ANOVA requires a post-test if your data is shown to be significant.
When doing a regression, do not average all your data. More points is better for
regression.
o List statistical tests used.
o Include -values when you talk about statistical tests. Since these are essentially arbitrary,
you must let the reader know what level of confidence you demanded.
o When talking about post-hoc tests, be specific. What type of test (T-tests with Bonferroni
corrections) and what adjusted -values?