Water and wastewater treatment produce sludge that is dewatered prior to disposal in order to reduce disposal costs. This work combined mathematical modelling of thickeners, filters and centrifuges with accurate measurement of sludge dewatering properties to give improvements in operation, design and control of such devices, including increased throughput and reduced water content. / The theoretical basis of this work was the phenomenological solid-liquid separation theory of Buscall and White, 1987, in which the local volume fraction dependent properties of compressive yield stress, Py(φ), and hindered settling function, R(φ) (which, when combined, give the solids diffusivity, D(φ)), describe the material behaviour in compression. The local conservation equations were given in vector notation, converted to one-dimension, and applied to piston-driven filtration. A range of models of plate-and-frame filter presses and solid-bowl centrifuges were developed. Simple visual basic programs were written to provide operators and designers access to filter model predictions. / Filtration and settling tests were used to measure the material characteristics for water and wastewater treatment sludges from a range of industrial sites, including different coagulants and coagulation conditions, with weekly and seasonal variations. The results showed that ferric-based water treatment sludges have very little variability, while alum sludges can exhibit some changes in properties. New qualitative and quantitative methods were developed for wastewater sludges, which exhibit atypical filtration behaviour. The production of synthetic sewage sludge showed that this is caused by the extracellular polymeric constituent. / The material characteristics were used to predict the throughput and cake solids for filter presses, centrifuges and continuous thickeners. The filter models were validated at a range of water treatment plants, and used to investigate the optimisation and control of press performance. A modified-Darcy’s law, which was validated using model predictions, was used to determine the membrane resistance from on-site measurements. / The centrifuge models included one-dimensional transient and continuous, and two-dimensional continuous decanting models. Algorithms for the solution of the one-dimensional models were developed for both the un-networked and networked cases, and the results for a simple example illustrated. The development of the decanting centrifuge model included conversion of the conservation equations to helical coordinates, consideration of the viscous flow of the centrate down the spiral formed by the blades of the scroll, the movement of the solids due to differential speed of the scroll and the sedimentation-consolidation of the solids due to the centrifugal acceleration. / Civil engineering consolidation theory and testing methods were outlined and compared to filtration. The relevant dewatering parameters were related via a simple equation. The material characteristics of a kaolin sample were measured using oedometer and pressure filtration testing and compared using the derived relationship. / Overall, this represents several important developments in the understanding of water and wastewater sludge dewatering, especially the measurement of water treatment sludge characteristics at a range of sites and with seasonal variations, the development of analysis techniques to determine wastewater sludge characteristics, and the development or adaptation of new or existing models of filters, centrifuges and thickeners. Considerable cost savings were made possible by understanding both the material behaviour and the dewatering device.

Thesis (M.S.)--University of Nevada, Reno, 2004. / "December 2004." Includes bibliographical references. Online version available on the World Wide Web.

<p>Skilsmässa är en vanlig samhällsföreteelse idag. Omfattande forskning visar att separationer får genomgripande konsekvenser för berörda familjer och att en rad faktorer påverkar den individuella anpassningsförmågan. Syftet med denna studie var att med kvalitativ metod beskriva upplevelserna av problem och stöd vid skilsmässa i Sverige. Materialinsamlingen skedde genom halvstrukturerade intervjuer med åtta separerade personer. Resultatet tolkades med hjälp av induktiv tematisk analys och knöts till befintliga teoretiska begrepp. Intervjupersonerna upplevde problem och stöd av interpersonell, materiell och personlig art vid separationen och önskade främst mer interpersonellt stöd. Centrala teman var relationen till expartner och barn samt den privata ekonomin. Resultatet överensstämde i väsentliga avseenden med tidigare forskningsrön, inklusive vissa påvisade kulturella skillnader. Studiens brister ligger främst i generaliserbarheten. Potentiellt stora långsiktiga kostnader för både individ och samhälle motiverar att det svenska samhällets stödinsatser ökas och inriktas på att minimera de negativa effekterna av separationer och underlätta anpassningen för alla inblandade.</p>

A series of compounds, 7-8 and 20-25, were tested as competitive inhibitors of 2,5-dihydroxyacetanilide epoxidase I (DHAE I) and DHAE II. A Hammett plot was constructed for each enzyme to determine the effect of electron density on inhibition. DHAE I gave a linear, highly correlated plot (r²=0.91) that signifies the importance of the amide oxygen in 1 on substrate binding. The plot for DHAE 11 is curved showing the greatest degree of inhibition with 7 suggesting steric factors within the active site control substrate binding. From these data, we conclude that each enzyme binds substrate in an opposite fashion and that this alone controls the stereochemistry of epoxide formation in 2 and 3. Alternative substrates, 26-29 and 33, were also synthesized and tested for product formation. All compounds, except 29, were accepted as alternative substrates, although the rates varied significantly. Surprisingly, 33 was accepted as an alternative substrate of DHAE II suggesting that the conformation of the amide bond in 33 is similar to the conformation required for catalytic activity in this enzyme. This information was then used to design ligands for affinity column separation of DHAE I and DHAE II from their protein mixtures. 35 and 36 were synthesized and attached to carbonyl di-imidazole activated agarose. Column I was tested three times with DHAE I enzyme preparations. The first attempt did not result in active enzyme being eluted from the column. The second attempt maintained the resin in the oxidized state. Protein was found to elute very quickly: no protein was found after fraction 4. The third attempt resulted in active enzyme in fractions 4-23. Column 2 was used twice for the attempted isolation of DHAE II from its protein mixture. The second attempt for column 2 mirrored the results for the third attempt with column 1. Neither column resulted in homogeneous enzyme by SDS-PAGE. / Graduation date: 2003

Isoelectric trapping (IET), has proven to be one of the most successful electrophoretic techniques used for separations of ampholytic compounds. IET is carried out in multicompartment electrolyzers (MCEs) in which adjacent compartments are joined through buffering membranes whose pH values bracket the pI of the ampholytic component to be trapped in the compartment. The present small-scale instruments use plastics as their structural materials, which causes poor Joule heat dissipation. The separation compartments have cylindrical or pear-shaped interiors with large internal diameters, which create long heat transfer paths. The long electrode distances yield low field strengths that lead to low electrophoretic velocities for the analytes. These factors interrelatedly limit the electric power that can be applied to the system, contributing to long separation times. Furthermore, these devices do not offer a realistic solution to the problems associated with the detection of low abundance proteins. To address these problems, two novel IET devices have been developed for small-scale IET separations. The first device, named MSWIFT, was constructed using thermally conductive, high-purity alumina as the structural material of the separation compartments. By creating narrow, 0.1- or 0.2-mL channels in thin alumina blocks, the heat transfer path from the center of the compartment to the wall was significantly decreased; and the distance between electrodes was greatly shortened. MSWIFT achieved 6 to 50 times faster IET separations compared to other MCEs. The second device, named ConFrac, was developed to simultaneously fractionate and concentrate ampholytic components from a complex sample into 0.1-mL collection compartments. By designing a system with a 2-dimensional pH gradient and allowing recirculation of the sample feed, the ConFrac demonstrated enrichment of analytes by a factor of 100 and greater.

Skilsmässa är en vanlig samhällsföreteelse idag. Omfattande forskning visar att separationer får genomgripande konsekvenser för berörda familjer och att en rad faktorer påverkar den individuella anpassningsförmågan. Syftet med denna studie var att med kvalitativ metod beskriva upplevelserna av problem och stöd vid skilsmässa i Sverige. Materialinsamlingen skedde genom halvstrukturerade intervjuer med åtta separerade personer. Resultatet tolkades med hjälp av induktiv tematisk analys och knöts till befintliga teoretiska begrepp. Intervjupersonerna upplevde problem och stöd av interpersonell, materiell och personlig art vid separationen och önskade främst mer interpersonellt stöd. Centrala teman var relationen till expartner och barn samt den privata ekonomin. Resultatet överensstämde i väsentliga avseenden med tidigare forskningsrön, inklusive vissa påvisade kulturella skillnader. Studiens brister ligger främst i generaliserbarheten. Potentiellt stora långsiktiga kostnader för både individ och samhälle motiverar att det svenska samhällets stödinsatser ökas och inriktas på att minimera de negativa effekterna av separationer och underlätta anpassningen för alla inblandade.

I denna studie undersöks den föräldraaktiva inskolningen ur ett anknytningsteoretiskt perspektiv. Syftet med studien är att undersöka hur små barn reagerar på separationen från sina föräldrar efter en föräldraaktiv inskolning. De frågeställningar som tas upp berör barnens beteenden och reaktioner efter den föräldraaktva inskolningen samt pedagogers och föräldrars syn på inskolningen. För att belysa syftet har kvalitativa metoder använts i form av observationer och semistrukturerade intervjuer med föräldrar och förskollärare. Studien omfattar fem barn bestående av två pojkar och tre flickor. De fem barnens föräldrar och två föräskollärare ingår även i urvalsgruppen. De fem barnen observerades i förskolan vid två olika tidpunkter efter det att den föräldraaktiva inskolningen var avslutad. Det har genomförts 3 observationer per dag och observationstillfälle. Totalt genomfördes 29 observationer samt 7 intervjuer med 5 föräldrar och 2 förskollärare. Att utgå från anknytningsteorin i kontakten med barn och pedagoger har gett en möjlighet att sätta fokus på barnets roll och separationsreaktioner efter den föräldraaktiva inskolningen. De beteenden som legat i fokus under alla observationer har sin utgångspunkt i anknytningsteorin när det gäller små barns reaktioner på separationer från sin primära anknytningsperson. Resultatet visar att en majoritet av barnen även efter en längre period på förskolan efter en föräldraaktiv inskolning visar starka separationsreaktioner och har ett stort behov av pedagogens närhet och lyhördhet.

I olika sammanhang och i olika omfattning separeras mor och barn idag inom den perinatala vården. Då barnet behöver vård på neonatalavdelning leder det ofta till upprepad och långvarig separation mellan föräldrarna och barnet. Syftet med denna litteraturstudie är att beskriva föräldrars upplevelse av separation från sitt nyfödda barn efter förlossningen. Metod- studien är en systematisk litteraturstudie där 15 vetenskapliga artiklar ingår. Resultat- situationer som leder till separation mellan mamma och barn kan utgöra ett unikt tillfälle för pappan till nära kontakt och tidig anknytning mellan honom och barnet. Behovet att vara nära sitt barn är starkt och finns hos båda föräldrarna och separation leder till många negativa känslor och ökad stress hos föräldrarna samt utgör ett hinder för den tidiga anknytningen till barnet. Skillnader i behovet att vara nära barnet i den tidiga nyföddhetsperioden kan ses mellan mammor och pappor och mellan föräldrar till prematura barn och fullgångna. Nära hudkontakt och samvård mellan föräldrar och barn har visat sig ha många positiva effekter. Slutsatser- separation mellan föräldrar och barn har många negativa konsekvenser, såväl fysiska, psykiska som sociala. Kontinuerlig närhet efter förlossningen mellan mamman och det nyfödda barnet är viktigt och närhet mellan pappan och det nyfödda barnet är att föredra vid de tillfällen mor och barn måste separeras. Neonatal samvård skapar förutsättningar för en god anknytning mellan föräldrar och barn och ger möjlighet att påbörja föräldraskapet under optimala förutsättningar.

Liquid and gas do not separate naturally in microgravity, presenting a problem for twophase space systems. Increased integration of multiphase systems requires a separation method adaptable to a variety of systems. Researchers at Texas A&M University (TAMU) have developed a microgravity vortex separator (MVS) capable of handling both a wide range of inlet conditions and changes in these conditions. To optimize the MVS design, the effects of nozzle area, separator geometry, and inlet flow rate must be understood. Computational fluid dynamics (CFD), in the form of Adapco’s Star-CD, is used, along with laboratory testing, to accomplish this goal. Furthermore, as analysis aids for the laboratory data and CFD results, relationships for radial pressure, bubble transit time, and momentum transfer were developed. Ground testing data showed a linear relationship between rotational speed and inlet flow rate. The CFD results compared well with the ground data and indicated that the majority of the rotational flow travels at nearly the same rotational speed. Examination of the tangential velocity profile also showed that a reduction of nozzle outlet area resulted in increased tangential velocities. Using dimensional analysis, a relationship between separator radius, inlet momentum rate, fluid properties, and rotational speed was found. Applying this relationship to the ground data and CFD results showed a strong correlation between the two dimensionless groups. Linear regression provided an equation linking rotational speed to the separator parameters. This equation was tested against the ground data and shown to predict average rotational speed well for all separator models. These results were used to calculate the radial and axial transit times of gas bubbles within the separation volume. Radial transit time was found to decrease more rapidly than axial transit time as gas volume increased, indicating axial and radial transit times are closest in value for the all liquid case and increasing gas core diameter improves the operational characteristics of the separator. From a design standpoint, the all liquid case provides a minimum flow rate for successful phase separation. Maximum flow rate depends on the pressure resources of the system.

Isoelectric trapping (IET), has proven to be one of the most successful electrophoretic techniques used for separations of ampholytic compounds. IET is carried out in multicompartment electrolyzers (MCEs) in which adjacent compartments are joined through buffering membranes whose pH values bracket the pI of the ampholytic component to be trapped in the compartment. The present small-scale instruments use plastics as their structural materials, which causes poor Joule heat dissipation. The separation compartments have cylindrical or pear-shaped interiors with large internal diameters, which create long heat transfer paths. The long electrode distances yield low field strengths that lead to low electrophoretic velocities for the analytes. These factors interrelatedly limit the electric power that can be applied to the system, contributing to long separation times. Furthermore, these devices do not offer a realistic solution to the problems associated with the detection of low abundance proteins. To address these problems, two novel IET devices have been developed for small-scale IET separations. The first device, named MSWIFT, was constructed using thermally conductive, high-purity alumina as the structural material of the separation compartments. By creating narrow, 0.1- or 0.2-mL channels in thin alumina blocks, the heat transfer path from the center of the compartment to the wall was significantly decreased; and the distance between electrodes was greatly shortened. MSWIFT achieved 6 to 50 times faster IET separations compared to other MCEs. The second device, named ConFrac, was developed to simultaneously fractionate and concentrate ampholytic components from a complex sample into 0.1-mL collection compartments. By designing a system with a 2-dimensional pH gradient and allowing recirculation of the sample feed, the ConFrac demonstrated enrichment of analytes by a factor of 100 and greater.