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Electrokinetic instability (EKI) emerges when fluids with differing electrical conductivities interact with an applied electric field, resulting in interfacial waves that can either disrupt or en-hance microfluidic processes. Previous studies on EKI have primarily focused on Newtonian flu-ids though many practical applications involve the mixing of different rheological fluids. This work investigates the effects of Newtonian and shear thinning rheology mixing on EKI using a T-shaped microchannel. We find that adding xanthan gum (XG) polymer to the high-conductivity buffer results in lower threshold electric fields and higher wave speeds/amplitudes than the con-figuration with XG in the low-conductivity buffer. In contrast, the threshold electric fields for the configuration with XG in both buffers are in between the two rheology mixing configurations. These findings suggest the gradient of rheology interacts with that of conductivity and may itself be able to induce instability in electrokinetic flows. We also perform a scaling analysis to account for the fluid shear thinning effect on the electric Rayleigh number in terms of a power-law model. The critical values of this dimensionless number for the onset of EKI exhibit similar variations to the threshold electric field across fluid configurations and XG concentrations. 

The number of students with multicultural experiences are growing in the United States. We define multicultural experiences as the multiple cultures that students experience in their early life and through family, which differs from the culture at their higher education institution. Many students immigrate to the US with their families after spending formative years in other countries, which gives them unique perspectives on multiple cultures. Multicultural engineering students have a different understanding of engineering from those without such experiences. These experiences both provide these students with certain advantages in engineering and present challenges in their educational pursuits. Examining both advantages and challenges provides an opportunity to understand these students’ strengths and adaptation strategies. Engineering is a field that requires new thoughts, insights, and opinions to advance. Their meaningful life experiences (particularly their multicultural experiences) can bring new light to issues in engineering as well. The study utilizes data from a larger mixed-methods study of Black students in engineering for in-depth interview transcripts, survey data, and an identity circle artifact. Two cases were purposefully selected for the current study – both participants were raised by African parents and had an additional international experience in a predominantly White country before studying engineering in the US. Both participants used this third point of reference to reflect on and give a rich description of their experience in the US. Through qualitative analysis of these cases, we will address the question: In what ways do Black students who are first- or second-generation immigrants from Africa and have studied abroad leverage community cultural wealth in engineering in the US? We use Yosso’s Community Cultural Wealth (CCW) framework to highlight the strengths these students leverage in engineering. CCW is an asset-based framework developed to highlight the strengths of the students from Communities of Color. There are six assets used as a guiding lens to inform research in these communities: familial, social, aspirational, navigational, resistance, and linguistic capital that students bring from their familial and community background. This framework names and categorizes the numerous skills Students of Color have obtained through lived experiences and how the students are able to be successful in academia. Furthermore, students have the ability to utilize these capitals to their advantage in order to be successful beyond academia. Exploring the CCW of Black immigrant students from African countries will give researchers a better understanding of the assets and strengths these students possess as well as the challenges they face. Through an examination of the CCW and various forms of capital for two Black immigrant students, we will emphasize the strengths of students with multicultural experiences in the hopes that they will be further valued and supported by university administrators. 

Asset-based theories explain how people can apply their talents and skills to thrive in diverse environments. When applied to engineering education, these theories can highlight the unique strengths of students of color that help them succeed in college and beyond. An asset-based framework allows both students and instructors to see the potential in students in ways that were previously overlooked or unexplored. This paper combines one asset-based framework and a powerful contextual theory to highlight the assets of Black students in engineering. First, Yosso’s Community Cultural Wealth (CCW) framework examines familial, linguistic, aspirational, resistant, navigational, and social capital. Second, Bronfenbrenner’s Ecological Systems Theory (EST) describes the relationships that surround an individual as a set of systems that influence the individual in different ways. We combine the CCW and EST frameworks, to develop the C2WEST framework. This new framework can be used explore the experiences and strengths of Black students in engineering and the contexts that best describe those strengths. The various levels of influence included in EST will be used as a tool for describing the proximity of the assets to the individual as described by CCW. We present an illustrative example to demonstrate the power of combining these two frameworks. We posit that synthesizing these frameworks provides researchers with unique opportunities to analyze interviews based on the type of capital and the impact the particular capital could have on the individual’s engineering journey. In addition to creating a unique way to analyze the experiences of Black engineering students, we anticipate the merged frameworks could be used to help students of Color realize the strengths they bring to the classroom. By identifying their assets, students could feel more empowered in engineering by recognizing the unique strengths they possess. We hope the tool will be used to help students realize their own strengths and for faculty and administrators to further realize how to support students.