Effects of Anionic and Nonionic Surfactant Mixtures on Bacterial Transport Through Unsaturated Porous Media

Effects of Anionic and Nonionic Surfactant Mixtures on Bacterial Transport Through Unsaturated Porous Media PDF Author: Shweta Tripathi
Publisher:
ISBN: 9780549631118
Category :
Languages : en
Pages : 170

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Book Description
A key aspect of the contamination of groundwater by pathogenic organisms is their transport through both unsaturated and saturated soils. An important source of these pathogens is domestic wastewater, which is released to the soil environment from on-site wastewater treatment systems, such as septic tanks. Surfactants---a major component of consumer detergents---are also present in domestic wastewater and have the potential to significantly enhance the transport of microorganisms through both unsaturated and saturated soils. The goal of this study was to explore how the surfactants present in domestic wastewater effect the bacterial transport through unsaturated porous media.

Effects of Anionic and Nonionic Surfactant Mixtures on Bacterial Transport Through Unsaturated Porous Media

Effects of Anionic and Nonionic Surfactant Mixtures on Bacterial Transport Through Unsaturated Porous Media PDF Author: Shweta Tripathi
Publisher:
ISBN: 9780549631118
Category :
Languages : en
Pages : 170

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Book Description
A key aspect of the contamination of groundwater by pathogenic organisms is their transport through both unsaturated and saturated soils. An important source of these pathogens is domestic wastewater, which is released to the soil environment from on-site wastewater treatment systems, such as septic tanks. Surfactants---a major component of consumer detergents---are also present in domestic wastewater and have the potential to significantly enhance the transport of microorganisms through both unsaturated and saturated soils. The goal of this study was to explore how the surfactants present in domestic wastewater effect the bacterial transport through unsaturated porous media.

Effects of Nonionic Surfactants on Becterial Transport Through Porous Media

Effects of Nonionic Surfactants on Becterial Transport Through Porous Media PDF Author: Derick Gerdts Brown
Publisher:
ISBN:
Category :
Languages : en
Pages : 458

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Effects of Concentration and Order of Addition of Nonionic Surfactant on Bacterial Adhesion

Effects of Concentration and Order of Addition of Nonionic Surfactant on Bacterial Adhesion PDF Author: Vamshi Gangupomu
Publisher:
ISBN:
Category : Bacteria
Languages : en
Pages : 102

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Book Description
Previous investigation has shown that nonionic surfactants reduce bacterial adhesion to surfaces by affecting the physicochemical interactions between the bacteria and the substrate. Nonionic surfactant molecules are known to adsorb to clean glass, quartz sand and to the surface of Sphingomonas species of bacteria. In this work, the extent of Brij-30 adsorption to E.coli and the resulting effects on the cells' adhesion to a glass surface was studied.

Bio-colloidal Transfer in Saturated and Unsaturated Porous Media

Bio-colloidal Transfer in Saturated and Unsaturated Porous Media PDF Author: Hongjuan Bai
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description
The investigation of the transport and retention of bacteria in porous media has a great practical importance in environmental applications, such as protection of the surface and groundwater supplies from contamination, risk assessment from microorganisms in groundwater, and soil bioremediation. The aim of this study is to gain a fundamental understanding of the mechanisms that control bacteria transport and deposition in saturated and unsaturated porous media. Laboratory tracer and bacteria transport experiments at Darcy scale were performed in three porous media with distinct pore size distribution in order to investigate and quantify water and bacteria transport process under steady state flow conditions. A conservative solute was used as water tracer to characterize water flow pathways through porous media. A gram negative, motile Escherichia coli, a gram negative, non-motile Klebsiella sp. and a gram positive, non-motile R. rhodochrous were selected for the transport experiments. Characterization of cell properties (such as cell size and shape, zeta potential, motility and hydrophobicity) was performed for each strain. Numerical simulations with HYDRUS-1D code were performed to characterize water flow and to estimate bacteria transport and deposition parameters. The later were explored to identify bacteria flow patterns and physicochemical or physical mechanisms involved in bacteria deposition. To provide a better understanding of the mechanisms involved on bacteria transport and deposition, pore scale experiments were carried out by using microfluidic devices, designed for this purpose. The information obtained from laboratory experiments and numerical modeling was improved by theoretical calculation of different interactions between bacteria and porous media at air/water/solid interfaces. DLVO and non-DLVO interactions such as hydrophobic, steric, capillary and hydrodynamic forces involved in bacteria deposition were considered to describe bacteria-interface interactions in order to identify their relative impact on physicochemical and physical deposition of bacteria. Results obtained through both laboratory experiments and numerical simulationsoutlined non-uniform flow pathways, which were dependent on both grain/pore size as well as pore size distribution of the porous media. For a given porous medium, water flow patterns became more non-uniform and dispersive with decreasing water saturation due to the presence of air phase, which lead to an increase of the tortuosity of the flow pathways under unsaturated conditions. Bacteria transport pathways were different from the tracer transport, due to size exclusion of bacteria from smaller pore spaces and bacteria motility. Bacteria deposition was greatly influenced by pore network geometry, cell properties and water saturation degree. Both physical straining and physicochemical attachment should be taken into account to well describe bacteria deposition, but their importance on bacteria deposition is closely linked to porous media and cell properties. The results obtained in this work highlighted the simultaneous role of cell properties, pore size distribution and hydrodynamics of the porous media on bacteria transport and deposition mechanisms. The calculation of DLVO and non-DLVO interactions showed that bacteria deposition in saturated and unsaturated porous media was influenced by both kinds of interactions.

The Influence of Nonionic Surfactants on Unsteady Water Flow in Unsaturated Porous Media

The Influence of Nonionic Surfactants on Unsteady Water Flow in Unsaturated Porous Media PDF Author: Mukhtar Ahmed Mustafa
Publisher:
ISBN:
Category : Groundwater flow
Languages : en
Pages : 116

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Transport of Bacteria in Unsaturated Porous Media

Transport of Bacteria in Unsaturated Porous Media PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 21

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Effects of Surfactant Concentration and Sorbent Properties on the Sorption and Transport of Ethoxylated Nonionic Surfactant Mixtures

Effects of Surfactant Concentration and Sorbent Properties on the Sorption and Transport of Ethoxylated Nonionic Surfactant Mixtures PDF Author: T. C. G. Kibbey
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Petroleum Abstracts

Petroleum Abstracts PDF Author:
Publisher:
ISBN:
Category : Petroleum
Languages : en
Pages : 1512

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Progress in Adhesion and Adhesives

Progress in Adhesion and Adhesives PDF Author: K. L. Mittal
Publisher: John Wiley & Sons
ISBN: 1119162327
Category : Technology & Engineering
Languages : en
Pages : 515

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Book Description
This book is based on the 13 review articles written by subject experts and published in 2014 in the Journal Reviews of Adhesion and Adhesives. The rationale for publication of this book is that currently the RAA has limited circulation, so this book provides broad exposure and dissemination of the concise, critical, illuminating, and thought-provoking review articles. The subjects of the reviews fall into 4 general areas: 1. Polymer surface modification 2. Biomedical, pharmaceutical and dental fields 3. Adhesives and adhesive joints 4. General Adhesion Aspects The topics covered include: Adhesion of condensed bodies at microscale; imparting adhesion property to silicone material; functionally graded adhesively bonded joints; synthetic adhesives for wood panels; adhesion theories in wood adhesive bonding; adhesion and surface issues in biocomposites and bionanocomposites; adhesion phenomena in pharmaceutical products and applications of AFM; cyanoacrylate adhesives in surgical applications; ways to generate monosort functionalized polyolefin surfaces; nano-enhanced adhesives; bonding dissimilar materials in dentistry; flame treatment of polymeric materials—relevance to adhesion; and mucoadhesive polymers for enhancing retention of ocular drug delivery.

Bibliography of Agriculture

Bibliography of Agriculture PDF Author:
Publisher:
ISBN:
Category : Agriculture
Languages : en
Pages : 2376

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Book Description