http://hdl.handle.net/10125/878 Thu, 23 May 2013 15:39:13 GMT 2013-05-23T15:39:13Z http://hdl.handle.net/10125/22263 Endocrine disrupting chemicals (EDCs) are a group of synthetic and natural chemicals that have the potential to mimic the hormone-like activities in the human body. This study was conducted to recognize whether recycled water (a source of EDCs) has the potential to contaminate the environment when such water is used for irrigation purposes. Batch sorption and miscible displacement experiments were conducted to elucidate the fate and transport of four EDCs including estrone, 17β estradiol, octylphenol and nonylphenol in a soil from Hawaii. The sorption capacity of the soil from two depths (2 ft as topsoil and 15 ft as saprolite) was estimated using recycled water and deionized water as the mobile phases. The transport parameters of these contaminants were obtained by using the inverse modeling approaches as provided in the HYDRUS 1D code. All four EDCs sorbed significantly on the soil. Octylphenol and Nonylphenol rapidly degraded during sorption. The Freundlich model was suitable to describe the sorption isotherm. The sorption nonlinearity was relatively higher for saprolite compared to topsoil. Both physical and chemical non-equilibrium processes were found to affect the mobility of the EDCs in the soil. The migration of EDCs in the soil was enhanced in recycled water due to the presence of dissolved organic carbon and elevated salt concentration. The ambient pH had little effect on sorption of EDCs on the soil from either depth. Tue, 01 Aug 2006 00:00:00 GMT http://hdl.handle.net/10125/22263 2006-08-01T00:00:00Z Mohanty, Sanjay K http://hdl.handle.net/10125/22251 Experiments were to study the effects of anionic polyacrylamide (PAM) on viruses and bacteria movement in soil. A water pollution problem which affects all areas with significant rainfall is soil erosion and subsequent transport of soil and all land-based pollutants. In recent year, high molecular weight polymers, such as anionic polyacrylamides (PAMs), have been used for soil erosion control and subsequent environmental problems. PAM is found to enhance infiltration. Land application of manure, sludge, and wastewater is common in many areas of the world, including the United States. Bacteria, viruses and other pathogens can be found in these waste materials. Studies must be conducts to evaluate if the use of polymers will allow water pollution constituents such as chemicals, pesticides, and microbial pathogens to reach groundwater in aquifer. Tue, 01 May 2001 00:00:00 GMT http://hdl.handle.net/10125/22251 2001-05-01T00:00:00Z Wong, Tiow P http://hdl.handle.net/10125/21919 A theoretical non-hydrostatic model is developed to describe the dynamics of a two-layer shallow water system in the presence of viscous and Coriolis effects. The Navier-Stokes equations are integrated over the water depth in each layer to obtain the layer-mean equations. To close the resulting equation set, perturbation expansions of the vertical momentum equation are used and the dynamic pressures are solved in terms of wave elevations and horizontal velocities. A preliminary analysis is also carried out and a result for the quasigeostrophic problems is given based on an previous study. Our final model is of the Bousinesq class which is nonlinear and dispersive, and includes the effects of surface wind stress, bottom friction, eddy diffusion and earth rotation. It is shown that our new model can be readily reduced to previous inviscid non-hydrostatic models. Our model can be used in numerical simulations to study real ocean problems such as hurricane generated waves, tidal induced current, and interactions among surface waves, internal waves and variable topographies. Thesis (M. S.)--University of Hawaii at Manoa, 1995.; Includes bibliographical references (leaves 55-59).; UHM: Has both book and microform. Tue, 01 Aug 1995 00:00:00 GMT http://hdl.handle.net/10125/21919 1995-08-01T00:00:00Z Ye, Feng http://hdl.handle.net/10125/21918 Two nanofiltration membranes, a thin film composite (TFC) membrane, a cellulose triacetate (CTA) membrane, were tested as pretreatment alternatives to extend the effective life of GAC at Mililani Wells I, Oahu, Hawaii. TFC membranes achieved excellent 1,2,3-trichloropropane (TCP), and 1,2-dibromo-3-chloropropane (DBCP) removal percentages whereas CTA membranes performed very poorly. TFC membranes showed promising signs of reducing total organic carbong (TOC) from the nanofiltration unit influent. In Mililani waters, only TCP is present in large amounts. It is suggested that further studies should be conducted where there is a chance of observing membrane's performance against high quantities of 1,2-dibromoethane (EDB), and DBCP. Due to the lack of trained personnel, not many TOC analyses were conducted. It is proven that nanofiltration is a viable treatment alternative and a pilot scale study should be conducted in the future taking economics also into consideration. Thesis (M. S.)--University of Hawaii at Manoa, 1995.; Includes bibliographical references (leaves 46-48).; UHM: Has both book and microform. Tue, 01 Aug 1995 00:00:00 GMT http://hdl.handle.net/10125/21918 1995-08-01T00:00:00Z Chaturvedula, Durgaprasad http://hdl.handle.net/10125/21913 Since actual carbon usage is much greater than predicted at the Granular Activated Carbon (GAC) plant in Mililani, operational costs are higher than estimated. Therefore, diffused aeration and mechanical mixing were examined as possible pretreatment alternatives for removing TCP and DBCP from Mililani groundwater before it enters the GAC plant. Various batch and continuous flow aeration configurations were examined by altering the water heights, air flows, and water flows. The amounts of TCP and DBCP in the Mililani water decreased after aeration pretreatment. Minicolumn experimental results show that the throughput volume before the breakthrough was increased and carbon usage rates were decreased. Therefore, the effective life of the GAC increased. The carbon capacity, i.e. the amount of pesticide adsorbed by the GAC, did not increase after aeration. Therefore, unknown background material not affected by aeration may be utilizing adsorption sites. Thesis (M. S.)--University of Hawaii at Manoa, 1992.; Includes bibliographical references (leaves 130-133).; University of Hawaii at Manoa: Has both book and microform. Tue, 01 Dec 1992 00:00:00 GMT http://hdl.handle.net/10125/21913 1992-12-01T00:00:00Z McParland, Terra L http://hdl.handle.net/10125/21912 Thesis (M. S.)--University of Hawaii at Manoa, 1992.; Includes bibliographical references (leaves 47-48).; Microfiche. Honolulu: University of Hawaii Library, 1992. 2 microfiches: negative.; Master negative: Microfiche MS32123.; UHM: Library has: Both book and microform. Sat, 01 Aug 1992 00:00:00 GMT http://hdl.handle.net/10125/21912 1992-08-01T00:00:00Z Chu, Holly Marie http://hdl.handle.net/10125/20496 Thesis (Ph.D.)--University of Hawaii at Manoa, 2008.; Design of composite structures in many important industrial applications requires good understanding of the fracture behavior in the vicinity of material interfaces. In this study, near-interfacial and interfacial fractures are modeled by the extended finite element method (XFEM), a numerical technique developed recently to model crack propagation. In the XFEM, a crack, or a discontinuity in displacements, is represented by enriching the nodes around the crack with additional degrees of freedom associated with enrichment interpolation functions. Among the advantages of the XFEM are that no remeshing is needed; the crack path is independent of the finite element mesh; it is applicable to preexisting cracks as well as evolving cracks; and it is numerically robust although extra implementation efforts are needed. In order to deal efficiently with changes in the geometry and mesh topology, the level set method (LSM), an algorithm used to track evolving interfaces, is introduced and combined with the XFEM.; The XFEM is first applied to the simulation of near-interfacial crack propagation in a metal-ceramic layered structure. Experimental evidence indicates that, in a ceramic-metal-ceramic sandwich structure, a near-interfacial crack in the ceramic layer can be drawn to or deflect away from the metal layer depending on the difference in elastic properties across the interface. To model near-interfacial fracture, only the Heaviside functions are used for the XFEM, and the vector LSM method, an improvement to the original LSM, where the LSM is adapted to the nature of crack propagation problems, is employed for efficient evaluation of the enrichment functions. The crack propagation paths predicted by the XFEM simulation are found to be consistent with the experimental observation. In the simulation of the interfacial fracture, a bi-material plate with a crack on the interface is modeled. In the proposed scheme, the nodes on the crack are enriched with only the Heaviside functions. The stress intensity factor analysis demonstrates that such an enrichment strategy can produce satisfactory results for interfacial fracture problems.; Includes bibliographical references (leaves 75-83).; Also available by subscription via World Wide Web; 83 leaves, bound 29 cm Tue, 01 Jan 2008 00:00:00 GMT http://hdl.handle.net/10125/20496 2008-01-01T00:00:00Z Yan, Yuhai http://hdl.handle.net/10125/20495 Thesis (M.S.)--University of Hawaii at Manoa, 2008.; Includes bibliographical references (leaves 82-91).; vii, 91 leaves, bound 29 cm Tue, 01 Jan 2008 00:00:00 GMT http://hdl.handle.net/10125/20495 2008-01-01T00:00:00Z Liu, Yuewei http://hdl.handle.net/10125/20494 Thesis (M.S.)--University of Hawaii at Manoa, 2007.; Includes bibliographical references (leaves 71-75).; xi, 75 leaves, bound 29 cm Mon, 01 Jan 2007 00:00:00 GMT http://hdl.handle.net/10125/20494 2007-01-01T00:00:00Z Li, Xiangang http://hdl.handle.net/10125/20493 Thesis (M.S.)--University of Hawaii at Manoa, 2007.; Includes bibliographical references (leaves 138-139).; x, 139 leaves, bound ill. (some col.) 29 cm Mon, 01 Jan 2007 00:00:00 GMT http://hdl.handle.net/10125/20493 2007-01-01T00:00:00Z Ishisaka, Renee http://hdl.handle.net/10125/20492 Thesis (M.S.)--University of Hawaii at Manoa, 2006.; Includes bibliographical references (leaves 113-114).; xi, 132 leaves, bound ill. 29 cm Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/10125/20492 2006-01-01T00:00:00Z Cheng, Huiping http://hdl.handle.net/10125/20491 Thesis (M.S.)--University of Hawaii at Manoa, 2006.; Includes bibliographical references (leaves 94-97).; xi, 97 leaves, bound ill. (some col.) 29 cm Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/10125/20491 2006-01-01T00:00:00Z Sharma, Bhavna http://hdl.handle.net/10125/20490 Thesis (M.S.)--University of Hawaii at Manoa, 2006.; Includes bibliographical references (leaves 89-93).; viii, 93 leaves, bound ill. 29 cm Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/10125/20490 2006-01-01T00:00:00Z Ng, Aileen http://hdl.handle.net/10125/20489 Thesis (M.S.)--University of Hawaii at Manoa, 2006.; Includes bibliographical references (leaves 131-144).; xiv, 144 leaves, bound ill. 29 cm Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/10125/20489 2006-01-01T00:00:00Z Mohanty, Sanjay K http://hdl.handle.net/10125/20488 Thesis (M.S.)--University of Hawaii at Manoa, 2006.; Includes bibliographical references (leaves 36-38).; x, 38 leaves, bound ill., map 29 cm Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/10125/20488 2006-01-01T00:00:00Z Lee, Seung Ha http://hdl.handle.net/10125/20487 Thesis (M.S.)--University of Hawaii at Manoa, 2006.; Includes bibliographical references (leaves 137-138).; xi, 138 leaves, bound ill. (some col.) 29 cm Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/10125/20487 2006-01-01T00:00:00Z Adams, Elizabeth http://hdl.handle.net/10125/20486 Thesis (M.S.)--University of Hawaii at Manoa, 2006.; Includes bibliographical references.; xi, 87 leaves, bound ill., maps 29 cm Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/10125/20486 2006-01-01T00:00:00Z Malalis, Ronald R http://hdl.handle.net/10125/20485 Thesis (M.S.)--University of Hawaii at Manoa, 2006.; Includes bibliographical references (leaves 87-92).; xi, 92 leaves, bound ill., col. maps 29 cm Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/10125/20485 2006-01-01T00:00:00Z Engott, John A http://hdl.handle.net/10125/20484 Thesis (M.S.)--University of Hawaii at Manoa, 2005.; Includes bibliographical references (leaves 104-105).; vi, 105 leaves, bound ill. (some col.), col. maps 29 cm Sat, 01 Jan 2005 00:00:00 GMT http://hdl.handle.net/10125/20484 2005-01-01T00:00:00Z Wallace, Carolyn D http://hdl.handle.net/10125/20483 Thesis (M.S.)--University of Hawaii at Manoa, 2005.; Includes bibliographical references (leaves 120-121).; xii, 282 leaves, bound ill. (some col.) 29 cm Sat, 01 Jan 2005 00:00:00 GMT http://hdl.handle.net/10125/20483 2005-01-01T00:00:00Z Okunaga, Grant J