HazeL: A Low-Cost Learning Platform for Aerosol Measurements

Abstract

The switch to online instruction during the COVID-19 pandemic forced educators to adapt hands-on environmental engineering experiments to a remote curriculum previously conducted in a laboratory using expensive analytical instruments (> $2000 per device). Here, we describe how we developed a low-cost (<$200) aerosol sensor platform as a successful solution for supporting remote laboratories on air quality for environmental engineering courses in Spring 2021, and continued for in-person classes in Spring 2022. This sensor platform, called HazeL (Haze Laser Sensor), consists of an externally mounted aerosol sensor, a GPS receiver, and temperature and pressure sensors coupled to an Arduino MKR WiFi 1010 microcontroller connected via a Grove system. Using a project-based learning approach and implementing the scientific method, students worked asynchronously to design experiments, collect aerosol measurements, and analyze and visualize data using the R programming language. Students generated hypotheses regarding factors affecting air pollution, measured ≥0.3 μm particles in different locations, tested differences between samples, and rejected the null hypothesis if appropriate. HazeL was also used for projects on data processing and statistical inference in an upper-level computational course. We present an instructional guide on manufacturing the HazeL platform and using it as a teaching tool for enhancing student experiential learning, participation, and engagement.

Building an Arduino-Based Open-Source Programmable Multichannel Syringe Pump: A Useful Tool for Fluid Delivery in Microfluidics and Flow Chemistry

“…The Arduino platform allows people to create quite impressive products in a very short period of time, and the 3D printer is a classic example of using Arduino in practice . With the aid of Arduino community, researchers have created many excellent lab-built instruments with low costs for data acquisition, analysis, and equipment control in chemical fields based on Arduino platform. ,,− A large number of Arduino-based teaching devices for chemical laboratory teaching have been developed, which greatly reduces the cost of chemistry teaching and provides a wealth of optional low-cost teaching devices for teachers engaged in chemistry laboratory teaching. ,− Moreover, based on Arduino microcontroller, chemical experiments can become more interesting, greatly expanding the teaching content and interest. − For syringe pumps, the core components are stepper motors and related mechanical parts that drive the precision movement of the syringe piston. And recently some articles related to the manufacture of syringe pumps have been reported in the literature. ,, Similar to the 3D printer, the heart of the syringe pump is the stepper motor and related mechanical components.…”

“Internet +” Automation Platform for Plate and Frame Filtering Experiment

“…Data Acquisition Device for Chemical Instrumentation, previously fabricated by the Grinias’ team, is a good example of the combination of Python and data acquisition; since Python is easy to learn, the software can be easily updated by different developers . Lower cost is also a very important aspect that many teams always pay attention to when developing teaching software. − …”

Use of Uncertainty Calculation Software as a Didactic Tool to Improve the Knowledge of Chemistry Students in Analytical Method Validation

“…Environmental education plays a critical role in creating a more aware, engaged, and capable society that can address environmental challenges. In the literature, some educational projects on measuring outdoor and indoor air quality using commercial sensors ,,− and passive air samplers , have been described. However, exercises based on the interpretation and visualization of atmospheric data are still scarce, and no didactic tools are available to assist students in the correct validation of these low-cost analyzers.…”