scholarly journals Groundwater Remediation of Volatile Organic Compounds Using Nanofiltration and Reverse Osmosis Membranes—A Field Study

Membranes ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 61
Author(s):  
Thomas J. Ainscough ◽  
Darren L. Oatley-Radcliffe ◽  
Andrew R. Barron
Keyword(s):  
Reverse Osmosis ◽  
Groundwater Remediation ◽  
Operating Pressure ◽  
Significant Extent ◽  
Groundwater Samples ◽  
Volatile Organic ◽  
Microfiltration Membranes ◽  
The Subject ◽  
A Site ◽  
Initial Results

Groundwater contamination by chlorinated hydrocarbons represents a particularly difficult separation to achieve and very little is published on the subject. In this paper, we explore the potential for the removal of chlorinated volatile and non-volatile organics from a site in Bedfordshire UK. The compounds of interest include trichloroethylene (TCE), tetrachloroethylene (PCE), cis-1,2-dichloroethylene (DCE), 2,2-dichloropropane (DCP) and vinyl chloride (VC). The separations were first tested in the laboratory. Microfiltration membranes were of no use in this separation. Nanofiltration membranes performed well and rejections of 70–93% were observed for synthetic solutions and up to 100% for real groundwater samples. Site trials were limited by space and power availability, which resulted in a maximum operating pressure of only 3 bar. Under these conditions, the nanofiltration membrane removed organic materials, but failed to remove VOCs to any significant extent. Initial results with a reverse osmosis membrane were positive, with 93% removal of the VOCs. However, subsequent samples taken demonstrated little removal. Several hypotheses were presented to explain this behavior and the most likely cause of the issue was fouling leading to adsorption of the VOCs onto the membrane and allowing passage through the membrane matrix.

Analysis and calculation of the process of low-pressure reverse osmosis during recycling of hygienic water

2019 ◽  
pp. 28-36
Author(s):  
Leonid S. Bobe ◽  
Nikolay A. Salnikov
Keyword(s):  
Mass Transfer ◽  
Reverse Osmosis ◽  
Life Support ◽  
Space Station ◽  
Low Pressure ◽  
Operating Pressure ◽  
Life Support System ◽  
Cleaning Agent ◽  
The Difference ◽  
Pressure Channel

Analysis and calculation have been conducted of the process of low-pressure reverse osmosis in the membrane apparatus of the system for recycling hygiene water for the space station. The paper describes the physics of the reverse osmosis treatment and determines the motive force of the process, which is the difference of effective pressures (operating pressure minus osmotic pressure) in the solution near the surface of the membrane and in the purified water. It is demonstrated that the membrane scrubbing action is accompanied by diffusion outflow of the cleaning agent components away from the membrane. The mass transfer coefficient and the difference of concentrations (and, accordingly, the difference of osmotic pressures) in the boundary layer of the pressure channel can be determined using an extended analogy between mass transfer and heat transfer. A procedure has been proposed and proven in an experiment for calculating the throughput of a reverse osmosis apparatus purifying the hygiene water obtained through the use of a cleaning agent used in sanitation and housekeeping procedures on Earth. Key words: life support system, hygiene water, water processing, low-pressure reverse osmosis, space station.

‘Yr Beast’: Gender Parrhesia and Punk Trans Womanhoods

2021 ◽  
Vol 127 (1) ◽  
pp. 119-134
Author(s):  
Jay Szpilka
Keyword(s):  
Embodied Experience ◽  
Challenges And Opportunities ◽  
The Subject ◽  
Trans Women ◽  
A Site ◽  
Significant Attention ◽  
The Way

While the subject of women’s activity in historical and contemporary punk scenes has attracted significant attention, the presence of trans women in punk has received comparatively little research, in spite of their increasing visibility and long history in punk. This article examines the conditions for trans women’s entrance in punk and the challenges and opportunities that it offers for their self-assertion. By linking Michel Foucault’s notion of parrhesia with the way trans women in punk do their gender, an attempt is made at showing how the embodied experience of a trans woman making herself heard from the punk stage can serve as a site of ‘gender pluralism’.

scholarly journals Scarred souls, weary warriors, and military intervention: the emergence of the subject in the just war writings of Jean Bethke Elshtain

2012 ◽  
Vol 39 (4) ◽  
pp. 859-880 ◽  
Author(s):  
PETER LEE
Keyword(s):  
International Relations ◽  
Political Theory ◽  
Just War ◽  
Military Intervention ◽  
Military Force ◽  
The Past ◽  
History Of ◽  
The Subject ◽  
Just War Tradition ◽  
A Site

AbstractOver the past three decades Jean Bethke Elshtain has used her critique and application of just war as a means of engaging with multiple overlapping aspects of identity. Though Elshtain ostensibly writes about war and the justice, or lack of justice, therein, she also uses just war a site of analysis within which different strands of subjectivity are investigated and articulated as part of her broader political theory. This article explores the proposition that Elshtain's most important contribution to the just war tradition is not be found in her provision of codes or her analysis of ad bellum or in bello criteria, conformity to which adjudges war or military intervention to be just or otherwise. Rather, that she enriches just war debate because of the unique and sometimes provocative perspective she brings as political theorist and International Relations scholar who adopts, adapts, and deploys familiar but, for some, uncomfortable discursive artefacts from the history of the Christian West: suffused with her own Christian faith and theology. In so doing she continually reminds us that human lives, with all their attendant political, social, and religious complexities, should be the focus when military force is used, or even proposed, for political ends.

scholarly journals Agency and Analogy in African History: the Contribution of Extra-Mural Studies in Ghana

2007 ◽  
Vol 34 ◽  
pp. 273-296 ◽  
Author(s):  
Kate Skinner
Keyword(s):  
Second World War ◽  
Gold Coast ◽  
Academic Disciplines ◽  
African History ◽  
World War ◽  
Significant Extent ◽  
The United Kingdom ◽  
Autobiographical Texts ◽  
The Subject ◽  
Second World

As the pioneering generation of postwar British academics retired, some produced autobiographical texts which revealed the personal circumstances and intellectual influences that brought them to the study of Africa. Edited volumes have also provided broader reflections on the academic disciplines, methodologies, and institutions through which these scholars engaged with the continent. In one such text, Christopher Clapham and Richard Hodder-Williams noted the special relationship between extramural studies (also known as university adult education) and the academic study of Africa's mass nationalist movements:The impetus for this study came to a remarkable degree from a tiny group of men and women who pioneered university extra-mural studies in the Gold Coast immediately after the [Second World War], and to a significant extent established the parameters for subsequent study of the subject [African politics]. Gathered together under the aegis of Thomas Hodgkin […], they were led by David Kimble […], and included among the tutors Dennis Austin, Lalage Bown and Bill Tordoff, all of whom were to play a major role in African studies in the United Kingdom over the next forty years.

scholarly journals For lack of a better word: neo-identities in non-cisgender, non-straight communities on Tumblr

2021 ◽  
Author(s):  
Christine Feraday
Keyword(s):  
Social Media ◽  
Academic Research ◽  
The Internet ◽  
Social Media Platforms ◽  
The Subject ◽  
The Creation ◽  
A Site

Non-cisgender and non-straight identity language has long been a site of contention and evolution. There has been an increase in new non-cisgender, non-straight identity words since the creation of the internet, thanks to social media platforms like Tumblr. Tumblr in particular has been host to many conversations about identity and self-naming, though these conversations have not yet been the subject of much academic research. Through interviews and analysis of Tumblr posts, this thesis examines the emergence of new identity words, or neo-identities, used by non-cisgender and non-straight users of Tumblr. The work presents neo-identities as strategies for resisting and challenging cisheteronormative conceptions of gender and attraction, as well as sources of comfort and relief for non-cisgender/non-straight people who feel ‘broken’ and excluded from mainstream identity categories. This thesis also posits that Tumblr is uniquely suited for conversations about identity because of its potential for self-expression, community, and anonymity.

A Vibration Monitoring/Fault Diagnosis Simulation Package

1995 ◽  
Vol 23 (2) ◽  
pp. 103-111
Author(s):  
I. A. Craighead
Keyword(s):  
Fault Diagnosis ◽  
Teaching Methods ◽  
Analytical Techniques ◽  
Vibration Monitoring ◽  
Traditional Teaching ◽  
Significant Extent ◽  
Traditional Teaching Methods ◽  
The Subject ◽  
Simulation Package ◽  
Real Plant

The subject of condition monitoring is becoming increasingly popular on engineering courses. One of the principal techniques used to assess the condition of plant and machinery is vibration monitoring. Traditional teaching methods can adequately present the analytical techniques to students and case studies illustrate their application but the art of diagnosing faults in machinery is usually not addressed to any significant extent. To overcome this deficiency a ‘game’ has been devised which gives students the opportunity to apply aspects of vibration monitoring to a simulated piece of real plant.

Deadhead Minimization with a Flexible Facility Locator Tool

2021 ◽  
pp. 036119812110444
Author(s):  
Kara Todd ◽  
Freyja Brandel-Tanis ◽  
Daniel Arias ◽  
Kari Edison Watkins
Keyword(s):  
Open Source Software ◽  
Operating Cost ◽  
Bus Rapid Transit ◽  
Rapid Transit ◽  
Flexible Tool ◽  
The Subject ◽  
Transit Agencies ◽  
A Site

As transit agencies expand, they may outgrow their existing bus storage and service facilities. When selecting a site for an additional facility, an important consideration is the change in bus deadhead time, which affects the agency’s operating costs. Minimizing bus deadhead time is the subject of many studies, though agencies may lack the necessary software or programming skill to implement those methods. This study presents a flexible tool for determination of bus facility location. Using the R dodgr package, it evaluates each candidate site based on a given bus network and existing depots and calculates the network minimum deadhead time for each potential set of facilities. Importantly, the tool could be used by any transit agency, no matter its resources. It runs on open-source software and uses only General Transit Feed Specification (GTFS) and data inputs readily available to transit agencies in the U.S.A., filling the accessibility gap identified in the literature. The tool is demonstrated through a case study with the Metropolitan Atlanta Rapid Transit Authority (MARTA), which is considering a new bus depot as it builds its bus rapid transit network. The case study used current MARTA bus GTFS data, existing depot locations, and vacant properties from Fulton County, Georgia. The tool evaluated 17 candidate sites and found that the winning site would save 29.7 deadhead hours on a typical weekday, which translates to more than $12,000 daily based on operating cost assumptions. The output provides important guidance to transit agencies evaluating sites for a new bus depot.

‘Agitate! Agitate! Agitate!’: Sport as a site for political activism and social change

Organization ◽  
2020 ◽  
Vol 27 (6) ◽  
pp. 952-968
Author(s):  
Kwame J. A. Agyemang ◽  
John N. Singer ◽  
Anthony J. Weems
Keyword(s):  
Social Change ◽  
Political Activism ◽  
Political Protest ◽  
Race And Racism ◽  
High Profile ◽  
The Us ◽  
The Subject ◽  
Nuanced Understanding ◽  
A Site ◽  
Coffee Shops

Is sport an appropriate forum for activists to engage in political protest? In recent years, this question has been the subject of conversations in households, public spaces such as barbershops and coffee shops, and social media and newsrooms, as various high-profile athletes have used their sport platforms to call attention to various social injustices existing within the US society. The purpose of the following interview is to provide further insight into this intersection between sport and politics and the use of sport as a site for political resistance and social change. Dave Zirin, a critical sports journalist, is the sports editor for The Nation and author of several books on the politics of sport. This interview with Dave Zirin offers a nuanced understanding on the recent occurrences involving athlete activism and the overall use of sport as a site for political activism and social change. Topics covered include race and racism in America, social responsibility, and social movements, among others.

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