Selective salt recovery from reverse osmosis concentrate using inter-stage ion exchange

A treatment process for reverse osmosis concentrate was developed to recover selected salts and increase fresh water recovery. The process utilizes cation and anion exchange to exchange all ions in the concentrate stream for sodium and chloride. The sodium chloride stream, with reduced scaling potential, can be treated further by a second reverse osmosis stage or another volume reduction technique to recover additional fresh water. The resulting concentrated sodium chloride stream can be used as ion exchange regeneration solution. Regeneration solutions from the cation and anion exchange columns are mixed to precipitate specific salts. In order to demonstrate the concepts behind this process, several phases of research were conducted. First, ion exchange batch isotherms were measured to characterize resin selectivity under ionic strength conditions common to reverse osmosis concentrate. A mathematical model was developed in which these isotherms were used to predict breakthrough curves. Regressions relationships developed from the batch tests were used in conjunction with the model to predict the number of bed volumes to breakthrough of calcium, magnesium, and sulfate. Model and regression relationships were verified by a series of column experiments. Attempts to separate ions during the regeneration process were not successful. Ion distribution within a loaded column was characterized using a specially designed column from which resin samples could be taken along the longitudinal axis. Third, simulated cation and anion regeneration solutions were combined to precipitate selected salts which were analyzed to determine their constituents. Finally, the process was tested with a continuously operated pilot scale system. Mixing of simulated and pilot generated cation and anion regeneration solutions resulted in precipitation of calcium sulfate when mixed at pH below 4.5 and mixed carbonate salts when pH was not adjusted. The pilot system can produce 12 kg of precipitate per cubic meter of regeneration solution and recover approximately 45% of the calcium and 28% of the sulfate

I Gotta Testify: Kanye West, Hip Hop, and the Church

The goal of this project, “I Gotta Testify: Kanye West, Hip Hop, and the Church,” is to add a new perspective to the scholarly discourse on Hip Hop and Christianity within classrooms, religious institutions, and popular culture by focusing on Kanye. We chose to focus on Kanye because he has been one of Hip Hop’s most influential artists in the past decade. Furthermore, Kanye is one of the most polarizing celebrities in America and across the globe. His music, fashion, political views, and family (which includes the Kardashians) dominate discourse on social media, blogs, television, and other forms of mass media. With the exception of Julius Bailey’s 2014 edited book, The Cultural Impact of Kanye West, there has been little scholarly work published on Kanye. Bailey’s book contained just one essay, written by Monica R. Miller, dedicated to the theme of Kanye and religion. We intended to produce a nontraditional journal issue, partly because Kanye has never adhered to traditional boundaries. We also chose this method because we wanted to provide a document suitable for both academic and popular audiences. Kanye West identifies as a Christian and primarily uses Christian themes in his music, videos, concerts, and messaging. Dr. Joshua K. Wright, Dr. Adria Y. Goldman and Dr. VaNatta S. For

Chaucer and the medieval sciences

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Humanities, 1972.Includes bibliographical references (leaf 51).by Joshua Aaron Goldman.B.S

Laptops and spatial use at MIT

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (p. 47-50).Individuals have a particular set of tasks they need to accomplish or what might be called a "life pattern." These tasks must be accomplished within a particular set of places or "life spaces." What is the role of the laptop in defining these life spaces and patterns and how does it either enable or constrain an individual from acting out their life pattern within a particular life space? This study uses a variety of quantitative and qualitative analytical methods for understanding the adaptation of student behavior to new technologies on MIT campus with a focus on the Sloan School of Management. Laptops will only enable spatial flexibility if the nature of one's work ("life pattern") affords it (Norman, 1999), "mobility" or "flexibility" is perceived to be advantageous, and there are suitable behavior settings (Barker, 1989; Schoggen, 1989) within their "life space." Most students are not creating "a new office" (Duffy, 1997) or choosing "special places" (Mitchell, 2003) to work. They mostly choose to use a very limited range of locations, often similar to office-type spaces. Only an exceptional minority of most techno-enabled are becoming free roaming "neonomads" (Abbas, 2005).(cont.) Rather than being more "mobile," most people are now more "connected" wherever they go (Castells, 2006). Instead, they might rather be labeled technologically enhanced cyborgs (Mitchell, 2003, Picon, 2000). Our relationship to the physical surrounding environment changes depending on the degree to which we require our technological enhancements and how much our cyborg selves are supported by that environment.by Ezra Goldman.M.C.P

Stimulating a Response: Does Exposure to the Confederate Flag Impact People’s Attitudes Regarding Social Dominance Orientation, Ethnocultural Empathy, and their Political Beliefs?

Minimal psychological research has looked at whether priming participants with the Confederate flag impacts psychological functioning. The current study examined whether Confederate flag priming and people’s political orientation would account for various indicators of how people reconcile in-group/out-group divisions- social dominance orientation (SDO) and ethnocultural empathy (EE). Previous research noted that exposing people to the Confederate flag activates schemas resulting in biased judgments of out-group members (Becker, Enders-Comber, Wagner, Christ, & Butz, 2012; Callahan & Ledgewood, 2016; Kemmelmeier & Winter, 2008). Other studies noted that exposure to the Confederate flag changed voter’s preferences for political candidates, such as Barack Obama due to the activation of negative feelings towards Blacks (Ehrlinger et al., 2011). The current study builds from such work by examining the political attitudes of 194 participants enrolled in a midsized, primarily minority-serving university in the southern United States. Participants were exposed to 30 seconds of either the Confederate flag or a control group condition (an Olympic flag). After the exposure, participants’ attitudes towards SDO and EE were reported. Findings indicated that political ideology interacted with the flag condition and that the disparities were most pronounced when people of a particular political orientation were exposed to the Confederate rather than Olympic flag condition. Specifically, when exposed to the Confederate flag conservatives reported more SDO (i.e., less endorsement of group equality) and less EE (e.g., empathic feelings). By contrast, for liberals EE empathic awareness subscale scores were especially higher in the Confederate flag condition. Multiple main effects also emerged in which liberals generally reported lower SDO and higher EE than conservatives did (regardless of the flag priming). Implications concerning the current political climate in the U. S. and information shortcuts for potential voting behavior are also discussed

Membrane Protein Production and Purification from Escherichia coli and Sf9 Insect Cells

A major obstacle to studying membrane proteins by biophysical techniques is the difficulty in producing sufficient amounts of materials for functional and structural studies. To overexpress the target membrane protein heterologously, especially an eukaryotic protein, a key step is to find the optimal host expression system and perform subsequent expression optimization. In this chapter, we describe protocols for screening membrane protein production using bacterial and insect cells, solubilization screening, large-scale production, and commonly used affinity chromatography purification methods. We discuss general optimization conditions, such as promoters and tags, and describe current techniques that can be used in any laboratory without specialized expensive equipment. Especially for insect cells, GFP fusions are particularly useful for localization and in-gel fluorescence detection of the proteins on SDS-PAGE. We give detailed protocols that can be used to screen the best expression and purification conditions for membrane protein study.Peer reviewe

The crystal structure of PD1, a Haemophilus surface fibril domain

The Haemophilus surface fibril (Hsf) is an unusually large trimeric autotransporter adhesin (TAA) expressed by the most virulent strains of H. influenzae. Hsf is known to mediate adhesion between pathogen and host, allowing the establishment of potentially deadly diseases such as epiglottitis, meningitis and pneumonia. While recent research has suggested that this TAA might adopt a novel `hairpin-like' architecture, the characterization of Hsf has been limited to in silico modelling and electron micrographs, with no high-resolution structural data available. Here, the crystal structure of Hsf putative domain 1 (PD1) is reported at 3.3 Å resolution. The structure corrects the previous domain annotation by revealing the presence of an unexpected N-terminal TrpRing domain. PD1 represents the first Hsf domain to be solved, and thus paves the way for further research on the `hairpin-like' hypothesis.Peer reviewe

Joining Together to Build More: The New England Software Carpentry Library Consortium

In 2017 a group of academic library and information technology staff from institutions across New England piloted a process of joining The Carpentries, an organization developed to train researchers in essential computing skills and practices for automating and improving their handling of data, as a consortium. The New England Software Carpentry Library Consortium (NESCLiC) shared a gold-level tier membership to become a Carpentries member organization. NESCLiC members attended a Software Carpentry workshop together and then participated in instructor training as a cohort, collaborating on learning the material, practicing, and beginning to host and teach workshops as a group. This article describes both the successes and challenges of forming this new consortium, suggests good practices for those who might wish to form similar collaborations, and discusses the future of this program and other efforts to help researchers improve their computing and data handling skills