Detecting Changes in Pressure Using a Graphene Field Effect Transistor

Graphene is a single, atomic layer, hexagonal lattice with useful electrical properties. Discovered as a stable isolated sheet in the early 2000s, graphene field effect transistors (GFET) are an effective way to detect small changes in electrical activity. When an electrolytic fluid is placed on a GFET, a double layer capacitor can develop at the interface between the fluid and graphene. Surprisingly, this interface is sensitive to barometric pressure, making GFETs a viable device for measuring pressure changes. In this work we built a pressure vessel and placed GFETs inside to test the performance limits of graphene based on its environment

Measuring the Effects of a Liquid Environment on Graphene Biotransistors

Mobility is a measure of the ease with which electrical carriers pass through a material. This work studies the mobility of graphene when measured within a liquid electrolyte environment. We use two different techniques to measure their mobilities at different concentrations of the electrolyte to compare results

crisscrossing Science Episode 031: Encore LIGO

The 2017 Nobel Prize winners were announced beginning the week of October 2. The Physics Prize for 2017 was awarded to three individuals: Rainer Weiss, Barry C. Barish, and Kip S. Thorne, for their work on LIGO, the Laser Interferometer Gravitational-Wave Observatory. In episode 007 of crisscrossing Science, Chris Gaiser (professor of biology at Linfield College) and Mike Crosser (professor of physics at Linfield College) discussed this experiment and the science behind it. Given the Nobel announcement, Crosser recorded a new introduction to the original episode. (To hear the original episode, click the link in the Related Resource field below.

crisscrossing Science Episode 045: Rebroadcast of How Muscles Work

In episode 015 of crisscrossing Science, Chris Gaiser (professor of biology at Linfield College) and Mike Crosser (professor of physics at Linfield College) chatted with David Altman (associate professor of physics at Willamette University) about his research into different forms of a protein called myosin. After meeting up again with Altman and some of his students, Crosser recorded a new introduction to the episode for this encore presentation. (To hear the original episode, click the link in the Related Resource field below.

Drag Coefficients of Varying Dimple Patterns

There are many golf balls on the market today with varying dimple sizes, shapes, and distribution. These proprietary differences are all designed to reduce drag on the balls during flight. There are limited published studies comparing how varying the dimples affects the reduction of drag. An experiment was developed in which golf balls were pulled through a water tank to measure the drag force acting on each ball. The water was chosen to allow for testing at slower velocities. A range of dimple patterns were tested and compared to determine which pattern has the lowest associated drag coefficient

crisscrossing Science Episode 073: Rebroadcast of Lightbulbs

In episode 060 of crisscrossing Science, Mike Crosser (professor of physics at Linfield College) and Chad Tillberg (professor of biology at Linfield College) discussed lightbulbs, how different types produce light, and which types of bulbs are better. Crosser recorded a new introduction to the episode for this encore presentation. (To hear the original episode, click the link in the Related Resource field below.

crisscrossing Science Episode 052: It\u27s Still Good to Be the Queen

In episode 012 of crisscrossing Science, Chris Gaiser (professor of biology at Linfield College) and Mike Crosser (professor of physics at Linfield College) invited Chad Tillberg (professor of biology at Linfield College) into the studio to discuss eusocial animals: bees, ants, wasps, and naked mole-rats. Each of these animal groups lives in a nest and has distinct classes of individuals, from workers to queens. Because Tillberg will be joining the crisscrossing Science team as a new co-host while Chris Gaiser is on sabbatical, Crosser recorded a new introduction so listeners can revisit the start of it all. (To hear the original episode, click the link in the Related Resource field below.

crisscrossing Science Episode 004: Oceans

In this episode, Chris Gaiser (professor of biology at Linfield College) and Mike Crosser (professor of physics at Linfield College) discuss the origins of the oceans on Earth, as well as what may happen to the oceans in the distant future

crisscrossing Science Episode 050: Biogeography: Why Things Are Where They Are

In episode 049 of crisscrossing Science, Chris Gaiser (professor of biology at Linfield College) and Mike Crosser (professor of physics at Linfield College) briefly touched on how biology and the similarity of organisms can tell us how recently organisms in different areas had been separated. This is a field called biogeography, and this is the topic for this episode. We consider how the Earth\u27s latitude affects life and how islands are interesting examples of isolated organisms evolving on their own

Modeling the Behavior of the Surface to Liquid Interfaces in an Electrolytic Liquid

Understanding the mechanism for charge transfer between electrodes within an electrolyte dissolved in water is vital to better understanding the sources of electrical noise in the system. This research compares the electrical properties of liquid top gated graphene devices with the properties of two metal probes to model the system. By measuring the impedance of these systems at different frequencies, it is possible to develop a model of their electrical properties and to consider techniques to improve signal to noise at graphene interfaces