Chapter 5
Smartphone Spectrometers: The Intersection of Environmental Chemistry and Engineering Downloaded by UNIV OF LEEDS on April 26, 2016 | http://pubs.acs.org Publication Date (Web): November 30, 2015 | doi: 10.1021/bk-2015-1214.ch005
A. Kahl* Environmental Engineering, Penn State Greater Allegheny, 4000 University Dr., McKeesport, Pennsylvania 15132, United States *E-mail:
[email protected] Project-based learning is an engaging way to allow undergraduate students to explore environmental chemistry by providing them with an open-ended problem to solve rather than the traditional format of prescribed laboratory exercises. This technique also allows for partnerships with other disciplines like engineering. In this exercise, chemistry and engineering students worked together using paper spectrometers originally designed by PublicLab. The students compared the performance of the paper spectrometer with existing instruments using prepared water samples and brainstormed how they might improve the design. Students also discussed how the portability of an instrument might affect field measurements and how “citizen science” can be used to get data. Students appreciated the interdisciplinary collaboration and felt that the activity enhanced their understanding of spectrometry beyond that of a traditional laboratory.
Introduction The changing nature of education necessitates novel approaches for teaching the next generation. Scientists must often cross interdisciplinary boundaries to develop solutions to environmental problems, and researchers must share knowledge across pedagogical borders (1, 2). Water resources, and clean water in particular, lend themselves to a non-traditional course approach, as the issue is current and evolving (3). Non-traditional students must also be engaged by course delivery, and one way in which to reach this audience is to provide links to real © 2015 American Chemical Society Lanigan et al.; Chemistry and the Environment: Pedagogical Models and Practices ACS Symposium Series; American Chemical Society: Washington, DC, 2015.
Downloaded by UNIV OF LEEDS on April 26, 2016 | http://pubs.acs.org Publication Date (Web): November 30, 2015 | doi: 10.1021/bk-2015-1214.ch005
world problems outside the classroom. These users benefit from interacting with their peers in ways which the traditional classroom can lack, as those students often feel that their opinions go unheard in the class “group-think. “The term non-traditional student refers to adult learners, or those who may have been away from the classroom for an extended length of time. Tilbury and Wortman have identified several skills that should be evident in sustainable chemistry environment, in particular systemic thinking and critical reasoning which we hoped to strengthen with this activity (4). In particular, these students often find themselves in the sciences and engineering as they hope to expand their career options.
Methods In this exercise, students from both general chemistry and engineering were scaffolded into the design challenge of evaluating tools for gaining community data about clean water with a series of lectures about water quality and analytical chemistry tools. This is the first time students have used a spectrophotometer so they were provided the schematic that appears in Figure 1.
Figure 1. Schematic of a single beam spectrophotometer. Students were primarily freshman and sophomore level with some adult learners. Students from general chemistry and engineering were participants in this project. Students worked separately for initial measurements of the water samples using the traditional spectrometer and then together as a combined class for the paper spectrometer. In-class discussions were held as a combined class as well. Students were required to attend regular class meetings as well as participate in the laboratory portion of both courses. Throughout the semester, students reflected upon their learning, and were occasionally surveyed regarding the courses. Unique cross-disciplinary topics included the chemistry of climate change, worldwide water usage, and hydraulic fracturing. The architecture of this environment has been to scaffold the student with a foundation of knowledge so that they not only understand the material, but interact actively with it by providing real world questions based in chemistry or engineering for students to explore. The scenario discussed herein is how to obtain crowd-sourced water quality data that can be used for communities to make decisions about their water resources. Students from chemistry and engineering courses worked cooperatively for this exercise. 70 Lanigan et al.; Chemistry and the Environment: Pedagogical Models and Practices ACS Symposium Series; American Chemical Society: Washington, DC, 2015.
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Our students are digital natives, so it was chosen by instructors to compare a smartphone paper spectrophotometer from PublicLab that allows one to gather data using a smartphone app with a traditional spectrophotometer. This spectrophotometer is comprised of a folded piece of heavy paper with a diffraction grating made from a piece of a DVD. The paper is folded to fit around the lens of a smartphone with the diffraction grating inside. The Public Laboratory for Open Technology and Science, known as PublicLab, is a non-profit organization that develops open source tools for environmental exploration investigation. PublicLab can be found on the web at publiclab.org. The traditional spectrometer was a recent model made by PASCO that is also lightweight, but with more bulk and that is run by computer application. These instruments are shown in Figures 2 and 3.
Figure 2. PublicLab smartphone spectrophotometer.
Figure 3. Traditional spectrophotometer. 71 Lanigan et al.; Chemistry and the Environment: Pedagogical Models and Practices ACS Symposium Series; American Chemical Society: Washington, DC, 2015.
Students then used these tools to evaluate prepared water samples. The prepared water sample consisted of tap water that had varying levels of ammonia present. Using HACH pillows, students reacted each water sample and then used the spectrophotometers to estimate the ammonia concentration. HACH pillows use ammonia cyanurate as a reagent to give a colorimetric estimate of the ammonia content. This bright color gradient gave students sufficient information for their spectrophotometers to estimate a measurement of the ammonia concentration as well as to evaluate the tools given. During this challenge, students were required to answer the following questions:
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Do smartphone spectrophotometers give good data compared to a traditional spectrophotometer? Are smartphone spectrophotometers easy to use? Could the design of the smartphone spectrophotometer be improved? In what way? What are potential spectrophotometer?
community
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Students answered these questions both orally and in the written form of a laboratory reflection. It was found that the smartphone spectrometers performed as well as the traditional spectrometers within a reasonable margin of error (10-15%). In the field, the smartphone devices were more portable and easier to use than the traditional spectrometers. Students critically evaluated the two instruments with regards to performance, ease of use and portability in their laboratory reflections. They were also required to redesign the smartphone spectrophotometer and present their design to the class.
Discussion The redesign activity resulted a series of student schematics, along with an extension activity discussing community or crowdsourced data in class. Students proposed many differences between the paper and traditional spectrometer. It was frequently noted that the traditional spectrometer is bulky and impractical for transport, while the smartphone spectrometer is small and portable. Students requested additional class time to talk about the topic, and were each granted 5 minutes to clarify and defend their designs in class. There was also additional discussion regarding citizen science, as students tried to think of ways that the smartphone tool could be used in the community. One student example of possible citizen science use was to give out paper spectrometers to residents affected by floodwaters as a way to measure water quality and changes over time. Others suggested that smartphone spectrometers could be used to create a database for areas affected by mine drainage. Students responded positively to the inclusion of the design challenge as a way to enhance interaction with course materials, 72 Lanigan et al.; Chemistry and the Environment: Pedagogical Models and Practices ACS Symposium Series; American Chemical Society: Washington, DC, 2015.
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all (n=50) citing either agree or strongly agree in answer to the question “Did the real world activities enhance your learning in this course?” One student noted that the interdisciplinary nature of the project “…helped me to see science from another’s’ perspective. It was great to work with my peers!” In response to the query “Did the redesign portion of the course help you feel more comfortable with the material?” all students except for one who responded neutrally (neither agree nor disagree) cited either agree or strongly agree as a response. Students also noted in the comments portion of the survey that presenting their ideas to the class helped them to better understand the material. One student put it thusly “Often in class I feel that I’m not quite sure I’m getting the entire concept. By presenting to the class I was able to refine my ideas and really grasp the material.”
Conclusions This novel course activity has resulted in an engaged student experience that provides in-depth topic exploration and familiarity with the material. Students benefited from the interaction with real world problems as well as the presentation of material by their peers to provide enhanced understanding. Students responded overwhelmingly positively to this activity, and it is planned to continue to include this type of engagement with material as a regular feature of the course.
Acknowledgments The author would like to acknowledge the support of the Penn State Greater Allegheny community during preparation of this submission.
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Kurland, N. B.; Michaud, K. E. H.; Best, M.; Wohldmann, E.; Cox, H.; Pontikis, K.; Vasishth, A Overcoming Silos: The Role of an Interdisciplinary Course in Shaping a Sustainability Network. Academy of Management Learning and Education 2010, 9 (3), 457–476. Michener, W. K.; Baerwald, T. J.; Firth, P.; Palmer, M. A.; Rosenberger, J. L.; Sandlin, E. A.; Zimmerman, H Defining and Unraveling Biocomplexity. BioScience 2001, 51 (12), 1018–1023. Parker, J Competencies for Interdisciplinarity in Higher Education. International Journal for Sustainability in Higher Education 2010, 11 (4), 325–338. Tilbury, D; Wortman, D. Engaging People in Sustainability; IUCN, The World Conservation Union: Gland, Switerzland and Cambridge, U.K., 2004; pp 81−91.
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