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Removal Of Reactive Azo Dyes From Water By Zero-Valent Iron Reduction Followed By Peroxidase-Catalyzed Polymerization., Mousumi Mani Biswas
Removal Of Reactive Azo Dyes From Water By Zero-Valent Iron Reduction Followed By Peroxidase-Catalyzed Polymerization., Mousumi Mani Biswas
Electronic Theses and Dissertations
Removing reactive azo dyes from textile wastewater is a significant challenge due to their color, non-biodegradability and toxicity. Although various treatment methods are available, it was hypothesized that reduction by zero-valent Fe followed by enzymatic treatment could be an environmentally friendly and cost effective approach. Zero-valent Fe cleaves the azo bond, reducing the dyes to aromatic amines, which are then oxidized and polymerized by enzymatic treatment. Finally, these polymers are removed by coagulant (PEI) aided sedimentation and filtration. The effectiveness of zero-valent Fe and Arthromyces ramosus peroxidase (ARP) treatment in the proposed process were studied on two representative reactive azo …
Strengthening Reinforced Concrete Column-Slab Connection Using Cfrp Sheets., Hazem Abou El-Enein
Strengthening Reinforced Concrete Column-Slab Connection Using Cfrp Sheets., Hazem Abou El-Enein
Electronic Theses and Dissertations
Due to the high cost of new construction and the increasing inventory of otherwise adequate structure, the need for repair, strengthening, or reinforced-concrete structures is growing significantly in Canada and worldwide. Fiber reinforced polymer technology has emerged during the past decade as a particular tool to upgrade existing structures. These materials are an excellent option for use as external reinforcing because of their light weight, resistance to corrosion, and high strength. This thesis introduces a strengthening technique of slab-column connection in flat-slab structures to enhance its flexural strength. Six flat-slab column connections were fabricated and then tested under increasing gravity …
The Effectiveness Of Life Cycle Inventories: Conceptual Data Versus Site-Specific Data., Faiza Iskandar Abdulrahem
The Effectiveness Of Life Cycle Inventories: Conceptual Data Versus Site-Specific Data., Faiza Iskandar Abdulrahem
Electronic Theses and Dissertations
Conducting a life cycle inventory (LCI) is the first step in carrying out a life cycle analysis (LCA). However, life cycle inventories are often based on surrogate or generic data because site specific data from the facility, product, or process in question does not yet exist or cannot be measured. This thesis investigates the effects of using different types of data on the credibility of life cycle inventories, and evaluates differences that exist between using site-specific data and conceptual sources of data. In particular, the thesis examines if a life cycle inventory developed by assuming data from external sources for …
Effect Of Welding On The Width Of The Heat-Affected Zone Of Aluminum Alloys., Vincent Aleo
Effect Of Welding On The Width Of The Heat-Affected Zone Of Aluminum Alloys., Vincent Aleo
Electronic Theses and Dissertations
Present aluminum design standards and specifications in North America require that the zone affected by welding be taken to extend a distance of 25 mm each side from the centre of the weld and that the yield strength of the metal in the zone affected by the weld be taken as the welded yield strength. The objective of this investigation is to determine the effect of welding on the width of the heat-affected zone (HAZ) of aluminum alloys. This was required for the development of an equation to determine the width of the HAZ for different parameters. One hundred and …
Determination Of The Equivalent Thickness Of Base Layer Of Flexible Pavement Reinforced By Geogrid., Md Badruzzaman
Determination Of The Equivalent Thickness Of Base Layer Of Flexible Pavement Reinforced By Geogrid., Md Badruzzaman
Electronic Theses and Dissertations
This thesis presents a numerical analysis for the determination of the equivalent thickness of a homogeneous base layer of an unreinforced multilayered system subjected to the repetitive loadings of a constant value. The system demonstrates the same performance as the analogous multilayered system does which contains the geogrid inclusion as reinforcement in the placement of interest of the base layer. The constitutive model adopted in the analysis is the modification of the small displacement theory of elastic continuum. Employing the proposed constitutive model the permanent modulus in each homogeneous isotropic layer of the unreinforced multilayered systems is determined for each …
Analysis Of Piles Embedded In P-Y Sand Below Water Table Subjected To Cyclic Lateral Loading: Sensitivity Analysis., T. I. M. Nazmur Rahman
Analysis Of Piles Embedded In P-Y Sand Below Water Table Subjected To Cyclic Lateral Loading: Sensitivity Analysis., T. I. M. Nazmur Rahman
Electronic Theses and Dissertations
The response of a pile to lateral loads and bending moments is a typical example of the soil-structure interaction system. The non-linear analysis of the pile-soil system can be conducted when the soil adjacent to the pile structure is described by means of p-y relationship. The sensitivity results in the form of sensitivity operators that affect the changes of the maximum generalized deformation of the pile-soil system caused by the changes of the variations of continuous design variables are discussed in detail. The quantitative assessment which physically represents the integration of each sensitivity integrand along the length of pile allows …
Advancement Of Waste Management Strategies In Developing Nations (Costa Rica)., Luis Alvarez
Advancement Of Waste Management Strategies In Developing Nations (Costa Rica)., Luis Alvarez
Electronic Theses and Dissertations
Planning a comprehensive waste management strategy in developing nations can be both difficult and markedly different from established waste practices in developed nations. Commonly accepted data sampling methods and approaches to waste management may have to be modified extensively to suit an area's unique characteristics. This thesis proposes a waste sampling protocol and a waste management strategy appropriate for developing nations. The proposed methods of study were tested with data from the cities of San Pablo and San Isidro in Costa Rica at the Las Joyas dumpsite. Volume based sampling was found to be a reasonable approach where truck weigh …
Inactivation Of Laccase And Enzymatic Removal Of Phenol From Water., Shovini Dasgupta
Inactivation Of Laccase And Enzymatic Removal Of Phenol From Water., Shovini Dasgupta
Electronic Theses and Dissertations
Laccase, as a developmental preparation from an industrial enzyme producer, catalyzes the oxidation of phenols. The reaction products are insoluble polymers and are readily removed from the solution. Experiments were conducted to evaluate the potential use of laccase in an alternative enzyme based treatment technology to remove parent phenol from buffered distilled water at room temperature. All tests were conducted in continuously stirred batch reactor. pH was optimized. At an optimum condition of pH, effects of substrate concentration, product formation, dissolved oxygen (DO) availability, hydrogen peroxide addition, and aeration on phenol removal were investigated. The turnover capacity of laccase (defined …
Short-Term Performance Of A Newly Developed Connection For Use In Precast Double Tee Systems., William D. Tape
Short-Term Performance Of A Newly Developed Connection For Use In Precast Double Tee Systems., William D. Tape
Electronic Theses and Dissertations
The focus of this work was to investigate the effectiveness of using advanced composite materials to enhance double tee to double tee connections in regions of significant seismic and lateral load. This work stems partly from the unfortunate losses experienced during the 1994 Northridge California earthquake. Moreover, this work was also developed from discussions with a local precasting company, which is concerned about premature failure of the connection due to stress concentrations. The author contends that the current connection method, intermittent welded plates, does result in stress concentrations, which can effect the system's overall performance. The proposed connection was formed …
Effects Of Submergence And Test Startup Conditions On Local Scour By Plane Turbulent Wall Jets., Niranjan P. Deshpande
Effects Of Submergence And Test Startup Conditions On Local Scour By Plane Turbulent Wall Jets., Niranjan P. Deshpande
Electronic Theses and Dissertations
Experiments were carried out to study the interaction of plane turbulent wall jets with cohesionless soils during scour. The jet of water having a constant mean velocity of 1.16 m/s and thickness of 25.4 mm at the nozzle exit was set to initially flow tangentially along the sand bed with a median grain size of 2.15 mm. Both scour profile measurements and velocity measurements were obtained for a range of submergences, defined by the ratio of the tailwater depth to the nozzle opening. The results confirm the presence of two distinct types of flow fields, one that occurs at lower …
Dynamic And Static Analyses Of Continuous Curved Composite Multiple-Box Girder Bridges., Magdy Said Samaan
Dynamic And Static Analyses Of Continuous Curved Composite Multiple-Box Girder Bridges., Magdy Said Samaan
Electronic Theses and Dissertations
Horizontally curved concrete deck on multiple steel box girder bridges is a structurally efficient, economic, and aesthetically pleasing method of supporting curved roadway systems. Modern highway constructions are often in need of bridges with horizontally curved alignments due to the tight geometry restrictions. Continuous curved composite box girder bridges allow for the use of longer spans, thus reducing costs of the substructure. Despite all inherent advantages of continuous curved composite box girder bridges, they do pose challenging problems for engineers in calculating the load distribution due to moving vehicles across the bridges. Curved bridges are subjected to high torsional as …
Piles Embedded In P-Y Sand Below Water Table Subjected To Static Loading-Sensitivity Investigations., Zain Al Abedin
Piles Embedded In P-Y Sand Below Water Table Subjected To Static Loading-Sensitivity Investigations., Zain Al Abedin
Electronic Theses and Dissertations
Laterally loaded pile is a complex system involving pile-soil interaction which is dependent on a number of parameters. The design process of laterally loaded pile is lengthy and at times obscure. This study aims at visualizing this process and relating performance of the pile to the design variables through sensitivity analysis. Short as well as long single piles, both hinged and fixed, embedded in sand, under different range of lateral static loads have been studied. Pile groups have also been studied. The behaviour of the pile is modeled by means of one dimensional beam element. The adjacent soil is simulated …
Predicting Spatial Distributions Of Sediments In Fluvial Environments Using Kriging And Flowline Based Distances., Jason S. Wintermute
Predicting Spatial Distributions Of Sediments In Fluvial Environments Using Kriging And Flowline Based Distances., Jason S. Wintermute
Electronic Theses and Dissertations
The process of predicting reasonable spatial distributions of surficial sediments in fluvial environments using interpolation techniques can be quite challenging. The process of sediment transport creates anisotropy in the spatial distributions that follow the direction of flow. Standard geostatistical software only allow for the incorporation of one anisotropy direction for the entire problem domain. This is problematic for fluvial environments because an average direction usually misrepresents the local changes in anisotropy throughout the river. A distance transformation technique based on flowlines was applied in an attempt to improve the way geostatistical algorithms deal with anisotropy. The standard geostatistical method of …
Sensitivity Analysis Of Laterally Loaded Piles Embedded In Stiff Clay Above Water Table., Lebing Liu
Sensitivity Analysis Of Laterally Loaded Piles Embedded In Stiff Clay Above Water Table., Lebing Liu
Electronic Theses and Dissertations
This study presents the theoretical formulation and numerical investigation of sensitivity analysis of laterally loaded piles embedded in stiff clay located above the water table. Single piles with various lengths and boundary conditions subjected to static and cyclic loadings applied to the pile-head as lateral forces and bending moments are analyzed. The cyclicity is introduced explicitly to p-y curve. The p-y soil response is of quasi static type. The pile groups of 3 x 3 piles with various spacing (2D, 3D, 4D and 5D) are also analyzed in the study. For single piles, the pile structure is considered as one-dimensional …