No description available.

No description available.

This experim ental project aims to describe the influencing factors in the vacuum boiling o f w ater in w ater vapour refrigeration system s Testing was conducted using a 2 kW three-stage steam je t ejector system, w ith barom etric condensers, as the com pression device. Three direct-contact evaporators were used to investigate the boiling phenom ena. T hese were : a through-flow evaporator w here heal and mass transfer rates were established for boiling m echanism s at various positions within the evaporator; a vertical cylinder where small quantities o f w ater were subjected to rapid decom pression and the effects m easured, and a sim ple channel for photographic studies o f the process. Boiling in direct-contact water vapour systems is described herein The vacuum boiling proo ss was found to be controlled by a com bination o f the w ater surface tem perature and the hydrostatic pressure gradient, these being governed by the w ater vapour flow geometry between the w ater surface and ejector suction and convective heat transfer below the boiling region. The contributions o f the various boiling regim es to the total heat transfer are discussed. Heat and mass transfer coefficients and their applicability to evaporator design are presented

Este trabalho tem como objetivo analisar e otimizar o desempenho de uma bomba hidráulica de fluxo através do redimensionamento de seu rotor. A partir da teoria acerca do pré-dimensionamento de rotores pelo método clássico (também conhecido como método geométrico) propõe-se uma planilha eletrônica que permite obter as dimensões básicas necessárias para o projeto de um rotor a partir de dados iniciais de operação e coeficientes empíricos. De modo a validar o dimensionamento teórico este trabalho apresenta um estudo de caso em uma bomba-teste. A partir dos dados do software de dimensionamento e recomendações coletadas na bibliografia um novo rotor é desenvolvido tendo como objetivo principal melhorar o desempenho de operação da bomba. Durante o desenvolvimento do novo rotor são utilizados aplicativos CAD e CAM de modo a auxiliar a elaboração do projeto e execução da usinagem. Uma bancada especial de teste de bombas é utilizada no levantamento dos dados experimentais. Os resultados dos ensaios demonstram um ganho máximo na eficiência de operação de 8% e redução de até 0,7 kW na potência da bomba operando com o novo rotor. / This work has as objective to analyze and to optimize the performance of a flow hydraulic pump by the re-design of pumps impeller. From the theory about impeller design by the classic method (also known as geometric method) proposes an electronic spread that allows obtaining the basic dimensions of impeller from initial pump operation data and empiric coefficients In order to validate the theoretical design this work presents a study of case on a pump test. From the design software data and recommendations collected in the bibliography review a new impeller is developed with the main objective to improve the pump performance. During the new impeller development are used applications CAD and CAM to aid the elaboration of the design and the execution of machining. A special hydraulic pump test bench is used to collect experimental data. The tests results shown a maximum gain of 8% in the efficiency of operation and a reduction of until 0,7 kW in the pump power consumption operating with the new impeller.

Renewable energy systems have received considerable attention as a sustainable technology in the building sector. Specifically, the use of ground-source heat pump (GSHP) and air-source heat pump (ASHP) for heating and cooling of buildings is increasing rapidly, and the combination with photovoltaic (PV) systems and heat pump systems provide energy savings and environmental benefits. This study investigates the feasibility of replacing conventional heating and cooling systems in a multifamily, residential building with GSHP and ASHP systems and their combination with PV. The integration of PV with GSHP and ASHP systems presents an opportunity for increased solar energy usage resulting in a reduction of electricity demanded and a reduction of emissions of greenhouse gases. To analyze different heat pumps systems with and without PV, system modeling and computer simulations are performed with RETScreen Expert software.<div><br></div><div>A multifaceted verification and validation study is conducted for the system model and computer simulation. The important objective of this part of the study is to understand and develop confidence for modelling individual studies in RETScreen Expert software. To accomplish this, RETScreen Expert is used for modeling and simulating the performance of PV systems in several geographical locations, including Fort Wayne, IN. A comparison is made to performance predictions from System Advisory Model (SAM) software. In addition, a study is done to compare predictions from both software to previously published data.<br></div><div><br></div><div>In the further phase of the study, eQUEST software, a tool for building energy simulation is used to predict outputs such as electricity consumption, heating loads, and cooling loads for the multifamily residential building considered in this study. These outputs, as well as, building parameters are used as inputs to RETScreen Expert. Since, this study focuses on modeling and simulating the heating and cooling systems coupled with PV for feasibility analysis, only a few minor modifications to the eQUEST default settings are made.<br></div><div><br></div><div>The outputs from eQUEST are used as inputs to RETScreen Expert and analysis of ASHP and GSHP systems, as well as their combination with a PV system are performed. The results include the technical performance and financial model of each system, which can be used to indicate feasibility. The results show that both GSHP and ASHP systems are environmentally friendly and reduce energy consumption. These systems are economically feasible, with payback periods of under 10 years, when electricity prices are high. When combined technology is preferred, PV-GSHP systems are more environmentally friendly and have fuel savings far better than any other proposed systems. But the feasibility of the both the GSHP and PV-GSHP systems strongly depends on loop installation cost.<br></div>

In this dissertation, I employed a combination of in vitro and in silico techniques to characterize two bacterial membrane proteins: the MtrE efflux conduit from Neisseria gonorrhoeae and the AmtB ammonia transporter from Escherichia coli. MtrE is an efflux conduit located in the outer membrane of N. gonorrhoeae. It can form a protein complex with MtrC (a periplasmic adapter) and MtrD (an inner membrane active transporter). This tripartite machinery actively extrudes a diverse set of compounds from the periplasm to the exterior of the bacteria. The MtrCDE complex and homologous tripartite efflux pumps are amongst the major contributors to the emergence of super-resistant Gram-negative bacteria. The efforts to abolish the activity of these protein complexes have so far concentrated on the inhibition of the active pump, but had little clinical success to date. I carried out a combination of Planar Lipid Bilayer electrophysiology experiments, Molecular Dynamics simulations, and protein homology modeling on the MtrE and the MtrC proteins. I characterized the MtrE conduit as being slightly cation selective, as opposed to other homologous proteins which exhibit a much stronger selectivity. Additionally, I demonstrated that the opening of MtrE is modulated by the binding of the adapter protein MtrC. These results have a critical importance because they imply that the tripartite pump activity can be diminished not only by the MtrD inhibition, but by targeting the interface between MtrC and MtrE. The AmtB ammonia transporter is a protein embedded in the inner membrane of E. coli in situations of growth-limiting low levels of ammonia. The transport has been shown to be electrogenic in similar orthologous proteins, but the exact mechanism has so far remained elusive. The only inner pathway that has been identified in AmtB is lined by hydrophobic amino acids and for this reason it has been proposed to carry neutral ammonia. My Molecular Dynamics simulations reveal the opening of a water wire separated from the well known hydrophobic pore. This finding suggests a transport mechanism in which the neutral ammonia and the proton travel along different conduits. My simulations on several AmtB mutants gave additional important insights into the protein function. Notably my results explain the structural determinants of the switching of substrate from NH4+ to K+ observed for the H168D/H318E double mutant. Lastly, I identified several 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol (POPG) binding sites on AmtB, which could possibly contribute to modulating the transport. Importantly, these in silico experiments were guided and confirmed by Solid Supported Membrane-electrophysiology measurements carried out in collaboration with the Javelle group. The data presented in this Thesis highlights the strength of a coordinated approach, in which experimental and computational findings direct, and integrate with each other.

No description available.

Nine pages of Addenda and eight pages of Errata in back pocket. / Includes bibliographical references. / vii, 192, [78] : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemical Engineering, 1994

This work examines electrohydrodynamic enhancement of capillary pump loops (CPL) for use in extraterrestrial nuclear applications. A capillary pump uses capillary action through a porous wick to transport heat and mass. The capillary pump is being considered as a method to improve heat transport in extraterrestrial nuclear applications. The work consists of a literature review of electrohydrodynamics, capillary pumped loops and space type nuclear reactors. Current CPLs are assessed for their performance and several design solutions are investigated using theoretical and analytical techniques. Experimental analysis is performed on an electrohydrodynamic gas pump to determine their suitability for implementation into the vapour leg of a capillary pump loop. The results suggest the EHD gas pumps could offer improved performance and it is recommended experiments should be performed in future work with an EHD gas pump in a CPL for verification. A new design for the electrohydrodynamic evaporator is also developed for enhanced performance. / UOIT

The primary objective of this research was to evaluate the effectiveness of a checklist, compared to a smart pump and bar-code verification system, at detecting different categories of errors in intravenous medication administration. To address this objective, a medication administration safety checklist was first developed in an iterative user-centered design process. The resulting checklist design was then used in a high-fidelity simulation experiment comparing the effectiveness of interventions towards two classifications of error: execution and planning errors. Results showed the checklist provided no additional benefit for error detection over the control condition of current nursing practice. Relative to the checklist group, the smart pump and bar-coding intervention demonstrated increased effectiveness at detecting planning errors. Results of this work will this work will help guide the selection, implementation and design of appropriate interventions for error mitigation in medication administration.