A simple one-dimensional heterogeneous-source model was used to simulate dissolution of organic liquid that was non-uniformly distributed in physically heterogeneous porous media. The permeability ...field was depicted as a pseudo-homogeneous medium. The source zone was discretized into multiple domains representing different organic-liquid configurations and hydraulic accessibilities, each with a different representative upscaled mass transfer rate coefficient that is temporally variable. This simplified approach represents a system where minimal information is available regarding system heterogeneities. All factors that influence dissolution were incorporated into the calibrated mass transfer terms. The mass transfer terms were calibrated for each zone separately. The one-dimensional, heterogeneous-source model adequately simulated the multi-stage dissolution behavior observed for column-scale systems that were packed with different natural soils, as well as for flow-cell systems wherein the source zone consisted of both a residual zone and pool. The results indicate that the model adequately simulated the presence of multiple organic-liquid zones in porous media with different configurations and hydraulic accessibilities, which accounts for the non-ideal dissolution behavior observed. The calibrated mass transfer terms for each source type were consistent with those obtained for systems that contained only one of either source type.
•NAPL dissolution in heterogeneous media was simulated by a 1D heterogeneous-source model.•The model simulated the presence of multiple organic-liquid domains in porous media.•The model adequately simulated the multi-stage dissolution behavior.•Incorporating the temporal change in mass transfer is important to simulate dissolution.
Multiphase-fluid distribution and flow is inherent in numerous areas of hydrology. Yet, pore-scale characterization of transitions between two and three immiscible-fluids is limited. The objective of ...this study was to examine the impact of such transitions on the pore-scale configuration of organic liquid in a multi-fluid system comprising natural porous media. Three-dimensional images of an organic liquid (trichloroethene) in two-phase (organic-liquid/water) and three-phase (air/organic-liquid/water) systems were obtained using X-ray microtomography before and after drainage and imbibition. Upon transition from a two-phase to a three-phase system, a significant portion of the organic liquid (intermediate wetting fluid) was observed to exist as lenses and films in contact with air (nonwetting fluid). In these cases, the air was either encased by or contiguous to the organic liquid. The presence of air resulted in an increase in the surface-area-to-volume ratios for the organic-liquid blobs. Upon imbibition, the air was displaced downgradient, and concomitantly, the morphology of the organic-liquid blobs no longer in contact with air reverted to that characteristic of a two-phase distribution (i.e., more spherical blobs and ganglia). This change in morphology resulted in a reduction in the surface-area-to-volume ratio. These results illustrate the impact of transitions between two-phase and three-phase conditions on fluid configuration, and they demonstrate the malleable nature of fluid configuration under dynamic, multiphase-flow conditions. The results have implications for characterizing and modeling pore-scale flow and mass-transfer processes.
As antiviolence activists and university professors teaching and learning about violence prevention and feminist movements, authors Laurie Fuller and Ann Russo write that they are inspired by the ...collaborative visioning of Critical Resistance and Incite! Women of Color Against Violence with regard to ending violence without reproducing it. Fuller and Russo have committed themselves to taking a vision of collective commitment based on guaranteeing the survival and care of all peoples into their women's and gender studies classrooms. They strive to create feminist community that practices building reciprocal and accountable relationships across the power lines produced by interlocking systems of racism, patriarchy, capitalism, and heteronormativity. They seek to develop and enhance our skills and imagination for collective responses to everyday oppression and violence that do not rely on policing or punishment. In this essay they share stories from their classrooms where using these teaching and learning skills demonstrates the possibilities and difficulties inherent in practicing collective responses to everyday oppression and violence. They draw from the work of small and large feminist groups across the country, inspired by the visionary work of Incite!
First published in 2001. Routledge is an imprint of Taylor & Francis, an informa company.
Ann Russo is Professor of Women's Studies at DePaul University. She has written for Sojourner and Women's ...Review of Books .
Column experiments were conducted using ideal natural sands and stainless-steel beads to examine the complete dissolution behavior of an organic immiscible liquid. Trichloroethene was used as the ...representative organic liquid. The elution curves exhibited multi-step behavior, with multiple extended periods of relatively constant contaminant flux. These secondary steady-state stages occurred at concentrations several orders-of-magnitude below aqueous solubility for the well-sorted sands. In contrast, the secondary steady-state stages occurred within 1 log of aqueous solubility for the poorly sorted sand. The non-ideal behavior is hypothesized to result from constraints to hydraulic accessibility of the organic liquid to flowing water, which may be expected to be mediated by the pore-scale configuration of the flow field and the fluid phases.
In this article, I reflect on relationship and movement building across power lines that I have experienced or witnessed in and outside of academia. I argue that the "anesthetic aesthetic" of ...whiteness, as illuminated by Mab Segrest, compels those like myself who are trained to be white to distance ourselves from the pain and suffering of others (as well as our own) in order to accept and assimilate into the hegemonic normative systems of power. I offer stories from my experience of feminist and queer organizing that demonstrate how this distancing looks and feels, and places of where it might be transformed. Then, I turn to healing justice as a praxis that creates communal spaces for naming, recognizing, and healing from violence, spaces to share our brokenheartedness, and to serve as a way of breaking up the gravitational pulls of white supremacist patriarchy.
This article explores two decolonial and healing justice projects from which the authors have attempted to make our own humanity visible, through reclaiming, testimonio, "re-membering" of and from ...our painful past through connecting, restoring, celebrating survival and joy, and envisioning alternative structures and conditions that embody an ethic of care. The first project is the Next Generation (NEXTGEN) "Pagbabalik" (Coming Home) Program, which supports second-generation Filipinx Americans to visit their home country for the first time. These trips have served as a cultural portal to a country of origin that has been impacted by over 350 years of colonialism, first by Spain and then by the United States, and from which many Filipinx leave behind to live in the land of their colonizers. It is a project designed to facilitate meaningful connection to a "homeland" that did not previously exist. The second project is the Healing Justice Dialogue Series, established to honor restorative justice practice involving peaceful resistance and indigenous practices of healing as forms of decolonization. These gatherings have encouraged critical self-reflection, steeping in our own discomfort, and acknowledging the healing many of our communities need amidst the anguish, rage, violence, illness, trauma, and loss they continue to disproportionately experience. Bridging our experiences between and within these two projects are our shared values, the most prominent being an ethic of care. As coconspirators invested in our individual and collective healing, we each share our testimonies and how these projects are a form of resistance, peacebuilding, and healing.
Public Significance Statement
With the use of testimonios, authors discuss two projects that engage an ethic of care by cultivating spaces in communal care and collective healing within academia and the Filipinx American community impacted by a history of colonization and trauma. These two projects serve as models that facilitate fundamental practices of a healing justice that seeks to mend, to heal as well as to dismantle interlocking systems of oppression and violence.
Epilogue ANN RUSSO
The Intersectional Approach,
01/2010
Book Chapter
The Intersectional Approach: Transforming the Academy through Race, Class, and Gendercould not be more timely. I say this in the face of the 2008 feminist debates over the U.S. Democratic Party ...primaries. On January 8, 2008, Gloria Steinem, in an Op-Ed for theNew York Times,urged people to vote for Hillary Clinton on the grounds that “women are never front-runners.” She wrote, “Gender is probably the most restricting force in American life, whether the question is who must be in the kitchen or who could be in the White House.” While she qualifies her argument with “I’m not
A series of column and flow cell experiments were conducted to investigate the impact of nonuniform organic liquid distribution on the relationship between reductions in contaminant mass discharge ...and reductions in source zone mass under conditions of enhanced-solubilization flushing. Trichloroethene was used as the model organic liquid, and sodium dodecyl sulfate and ethanol were used as representative enhanced-flushing reagents. The results were compared to those of waterflood control experiments. Concentrations of trichloroethene in the effluent exhibited a multi-step behavior with time, wherein multiple secondary periods of quasi steady state were observed. This nonideal behavior was observed for both the waterflood and enhanced-flushing experiments. For all flow cell experiments, the later stage of mass removal was controlled by the more poorly accessible mass associated with higher-saturation zones. The profiles relating reductions in contaminant mass discharge and reductions in mass exhibited a generally similar behavior for both the waterflood and enhanced-flushing experiments. This indicates that while the rates and magnitudes of mass removal are altered by the presence of a solubilization reagent solution, the fundamental mass removal process is not. The profiles obtained for the flow cell systems differed from those obtained for the column systems, highlighting the impact of source zone heterogeneity on mass removal behavior.
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