Satetha Siyang

E-nose based on metallo-tetraphenylporphyrin/ SWNT-COOH for alcohol detection

A handheld electronic nose (e-nose) based on metallo-tetraphenylporphyrin/carboxylic-functionalized single- walled carbon nanotube (MTPP/SWNT-COOH) chemical gas sensors has been demonstrated as a promising instrument for monitoring in food production process. In this work, the gas sensor array was fabricated by dispersing SWNT-COOH in the matrix of different MTPP compounds, namely, MnTPP, FeTPP, ZnTPP, CoTPP and CuTPP. The sensing responses were studied in terms of the changing sensor resistance under the atmosphere of various volatile compounds. The results show that the central metals in tetraphenylporphyrin (TPP) ring play a major role in the selectivity of each gas sensor to each volatile gas. We have investigated the functionality of this handheld e-nose by monitoring the odor of fermented rice during the 5-day fermentation process. Based on the principal component analysis, it was found that the handheld e-nose can track the change of odors generated from the fermentation, in which largest odor change happens on the fifth day.

Low cost weather station for climate-smart agriculture

Climate-smart agriculture is one of the techniques that maximizes agricultural outputs through proper management of inputs based on climatological conditions. Real-time weather monitoring system is an important tool to monitor the climatic conditions of a farm because many of the farms related problems can be solved by better understanding of the surrounding weather conditions. There are various designs of weather monitoring stations based on different technological modules. However, different monitoring technologies provide different data sets, thus creating vagueness in accuracy of the weather parameters measured. In this paper, a weather station was designed and deployed in an Edamame farm, and its meteorological data are compared with the commercial Davis Vantage Pro2 installed at the same farm. The results show that the lab-made weather monitoring system is equivalently efficient to measure various weather parameters. Therefore, the designed system welcomes low-income farmers to integrate it into their climate-smart farming practice.

Indoor air quality monitoring system based on polymer/functionalized-SWNT gas sensors

Recently, people pay more attention to healthy living conditions. Such changing lifestyle leads to demand for wearable health monitoring, new medical technology, healthy food and clean air. Thus, indoor air monitoring and control will be an emerging industry with a huge market size. In this paper, we have developed an indoor air monitoring system with ability to observe volatile contaminants, especially related to household origin. This system consists of an array of chemical gas sensor based on polymer/functionalized single-walled carbon nanotubes (SWNT) with ability to detect different gases. A microcontroller was used for data processing and alarming when the concentration of a target gas becomes danger. This system was developed based on consumer-friendly having a compact size and using low-cost technologies. From the experiment, it was demonstrated that such indoor air monitoring device provides an ability to detect contaminated gases in ambient air. The results imply a possibility appropriate for indoor air monitoring in general home and even in factory as well.