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2012

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Full-Text Articles in Engineering

An Assessment Of The Effects Of Desertification In Yobe State, Nigeria, Jibril Musa Phd Dec 2012

An Assessment Of The Effects Of Desertification In Yobe State, Nigeria, Jibril Musa Phd

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

Desertification is one of the most serious environmental and socio-economic problems of our time. Desertification describes circumstances of land degradation in arid, semi-arid and dry sub-humid regions resulting from the climatic variation and human activities. The fundamental goal of this thesis was to assess the effects of desertification in Yobe State, Nigeria. The present threat of desertification in the sahel has reached an alarming stage where crops cultivation and animal rearing/grazing are no more productive, soil has lost its nutrient/fertility, various infrastructure had given way because of windstorm from the neighbouring Niger Republic and sand dunes had taken over. The …


Using Remote Sensing Data To Improve Rice Production In Kutigi, Niger State, Nigeria, Jibril Musa Phd, M B. Yunusa Dec 2012

Using Remote Sensing Data To Improve Rice Production In Kutigi, Niger State, Nigeria, Jibril Musa Phd, M B. Yunusa

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

This research work looked in the used of Remote Sensing to improve Agricultural production in Kutigi, Niger State. The aim of the study is to use remote sensing to improve rice farming activities in Kutigi, Niger State. It is very important to identify such methods to improve Agricultural production because experts are always interested in new researches and findings to better the standard of living in any environment. In view of this, Remotely-sensed data could be used or employed to elevate most of these agricultural problems in Kutigi through the following objectives: Using Landsat imagery to assess the present landuse …


Topographic Influences On Trends And Cycles In Nutrient Export From Forested Catchments On The Precambrian Shield, Samson G. Mengistu Dec 2012

Topographic Influences On Trends And Cycles In Nutrient Export From Forested Catchments On The Precambrian Shield, Samson G. Mengistu

Electronic Thesis and Dissertation Repository

This dissertation explored topographic controls on spatial and temporal patterns in water yield and nutrient (carbon, nitrogen and phosphorus) export from forested headwater catchments in the Turkey Lakes Watershed in central Ontario, where other factors contributing to differences in water yield and nutrient export, including climate, geology, forest, and soils, are relatively constant. Topographic characteristics, including (a) hydrological flushing potential (expansion of water table into nitrate-N producing areas); (b) hydrological storage potential (area of wetlands, which can alternatively allow water and nutrients to bypass wetlands when storage capacity is filled with water or to trap them when not filled); and …


Modelling Three-Phase Flow In Metallurgical Processes, Christoph Goniva, Gijsbert Wierink, Kari Heiskanen, Stefan Pirker, Christoph Kloss Dec 2012

Modelling Three-Phase Flow In Metallurgical Processes, Christoph Goniva, Gijsbert Wierink, Kari Heiskanen, Stefan Pirker, Christoph Kloss

Gijsbert Wierink

The interaction between gasses, liquids, and solids plays a critical role in many processes, such as coating, granulation and the blast furnace process. In this paper we present a comprehensive numerical model for three phase flow including droplets, particles and gas. By means of a coupled Computational Fluid Dynamics (CFD) - Discrete Element Method (DEM) approach the physical core phenomena are pictured at a detailed level. Sub-models for droplet deformation, breakup and coalescence as well as droplet-particle and wet particle-particle interaction are applied. The feasibility of this model approach is demonstrated by its application to a rotating drum coater. The …


A Watershed Scale Evaluation Of Selected Second Generation Biofeedstocks On Water Quality, Gurdeep Singh Dec 2012

A Watershed Scale Evaluation Of Selected Second Generation Biofeedstocks On Water Quality, Gurdeep Singh

Graduate Theses and Dissertations

This study compares a novel simulation approach to the conventional Soil and Water Assessment Tool (SWAT) modeler's approach for targeting biofuel crop production on marginal lands. In conventional SWAT modeling approach, non-spatial definition of hydrological response units (HRUs) results in the simulation of biofuel crops on both marginal and non-marginal land. This study provides an alternative approach in which a marginal-land raster was integrated into the land use and land cover (LULC) raster in such a way that the land uses were divided into marginal and non-marginal components. This modified LULC was used for model setup which resulted in marginal …


Study On Pore Distribution And Formation Rule Of Sepiolite Mineral Nanomaterials, Qingguo Tang, Fei Wang, Mengran Tang, Jinsheng Liang, Chongyan Ren Nov 2012

Study On Pore Distribution And Formation Rule Of Sepiolite Mineral Nanomaterials, Qingguo Tang, Fei Wang, Mengran Tang, Jinsheng Liang, Chongyan Ren

Electrical and Computer Engineering Faculty Publications

Theoretical research and specific surface area analysis of nitrogen adsorption indicated that a lot of structural micropores exist in sepiolite minerals fibers. However, the microporous size, existing form, and the distribution relationship between microporous structures were not proved yet. In this paper, the section TEM samples of nanofibers were prepared on the basis of the metal embedding and cutting technique, and the inner structure of sepiolite nanofibers was observed by TEM. The results showed that sepiolite fibers have multiplayer structure similar to concentric circles, and many micropores with the size of about 2–5 nm are normal and parallel to the …


Development Of A Ground Based Remote Sensing Approach For Direct Evaluation Of Aerosol-Cloud Interaction, Bomidi Lakshmi Madhavan, Yuzhe He, Yonghua Wu, Barry Gross, Fred Moshary, Samir Ahmed Oct 2012

Development Of A Ground Based Remote Sensing Approach For Direct Evaluation Of Aerosol-Cloud Interaction, Bomidi Lakshmi Madhavan, Yuzhe He, Yonghua Wu, Barry Gross, Fred Moshary, Samir Ahmed

Publications and Research

The possible interaction and modification of cloud properties due to aerosols is one of the most poorly understood mechanisms within climate studies, resulting in the most significant uncertainty as regards radiation budgeting. In this study, we explore direct ground based remote sensing methods to assess the Aerosol-Cloud Indirect Effect directly, as space-borne retrievals are not directly suitable for simultaneous aerosol/cloud retrievals. To illustrate some of these difficulties, a statistical assessment of existing multispectral imagers on geostationary (e.g., GOES)/Moderate Resolution Imaging Spectroradiometer (MODIS) satellite retrievals of the Cloud Droplet Effective Radius (Reff) showed significant biases especially at larger solar zenith angles, …


Variations In Climatic Parameters And Food Crop Yields: Implications On Food Security In Benue State, Nigeria., Emmanuel Adamgbe, Fanan Ujoh Oct 2012

Variations In Climatic Parameters And Food Crop Yields: Implications On Food Security In Benue State, Nigeria., Emmanuel Adamgbe, Fanan Ujoh

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

Agricultural production in Nigeria like in other developing countries is highly vulnerable to variations in climatic parameters which may have inverse or direct effect on the performance of food crops. This paper examines the patterns and trends of the variations in the climatic parameters and the implications of such variations on efficient yield rates of some food crops in Benue State using data on climatic variables (rainfall, temperature, sunshine) and the yield of some crops per hectare for 25 years (1986-2010). Data on the climatic variables were collected from the Nigerian Meteorological Agency, AirForce Base, Makurdi while the data on …


Identifying The Retention Mechanisms Of (Bio)Colloids In Single, Saturated, Variable-Aperture Fractures, Sandrina Rodrigues Oct 2012

Identifying The Retention Mechanisms Of (Bio)Colloids In Single, Saturated, Variable-Aperture Fractures, Sandrina Rodrigues

Sarah E Dickson

No abstract provided.


First-Order Catchment Mass Balance During The Wet Season In The Panama Canal Watershed, Fred Ogden Aug 2012

First-Order Catchment Mass Balance During The Wet Season In The Panama Canal Watershed, Fred Ogden

Fred L. Ogden

Tropical hydrology is poorly understood for a number of reasons. Intense biological activity in the tropics introduces complexities to the hydrologic process. Bioturbation, rapid rates of decay, and intensive insect activity all tend to promote rapid flow paths in the upper soil. Aggressive weathering leads to clays depleted of light cations and deep soil profiles. Processes in the seasonal tropics are further complicated by seasonal transitions, and very large changes in catchment storage between seasons. Beginning in 2005, we installed a suite of hydrologic sensors in a 16.7 ha first-order catchment in the Panama Canal Watershed to observe hydrologic variables …


Electric Currents Due To Stress-Activated Positive Hole Charge Carriers In Ice, Cary T. Keller P.E., Friedemann T. Freund, Dale P. Cruikshank Aug 2012

Electric Currents Due To Stress-Activated Positive Hole Charge Carriers In Ice, Cary T. Keller P.E., Friedemann T. Freund, Dale P. Cruikshank

STAR Program Research Presentations

Jupiter’s satellite Europa, whose surface is composed of ice with a possible water ocean beneath, could conceivably serve as an abode for extraterrestrial life. This and other icy celestial bodies may contain organic macromolecular solid material that is produced when surface ices are exposed to ultraviolet radiation and/or electrical energy. Tidal and tectonic stresses or meteorite impacts in icy crusts may produce electrical discharges, which would provide the energy for in-situ synthesis of the organic solids. This electrical energy can be provided by positive hole charge carrier activation. Positive holes exhibit properties such as the ability to flow out of …


Investigation Of Spillover Effect To Enhance Hydrogen Storage, Sarah C. Corrigan, Lin Simpson, Thomas Gennett Aug 2012

Investigation Of Spillover Effect To Enhance Hydrogen Storage, Sarah C. Corrigan, Lin Simpson, Thomas Gennett

STAR Program Research Presentations

Hydrogen is an attractive energy option because of its low
environmental impact, but a critical problem is its low energy
density, which makes it difficult to store. For example, the US
Department of Energy (DOE) hydrogen plan for fuel cell powered
vehicles requires a gravimetric density of 6.5 wt%. There are several
existing hydrogen storage methods, including compressed gas,
liquefaction, metal hydrides, and physisorption, but at present, none
of these technologies comes close to achieving the targets set by the
DOE. Although chemical storage methods have been claimed to be the
most promising hydrogen storage technology, and activated carbons the …


Environmental Impacts Of Stover Removal In The Corn Belt, Alicia English, Wallace E. Tyner, Juan Sesmero, Phillip Owens, David J. Muth Jr. Aug 2012

Environmental Impacts Of Stover Removal In The Corn Belt, Alicia English, Wallace E. Tyner, Juan Sesmero, Phillip Owens, David J. Muth Jr.

David J. Muth

When considering the market for biomass from corn stover resources erosion and soil quality issues are important to consider. Removal of stover can be beneficial in some areas, especially when coordinated with other conservation practices, such as vegetative barrier strips and cover crops. However, benefits are highly dependent on several factors, namely if farmers see costs and benefits associated with erosion and the tradeoffs with the removal of biomass. This paper uses results from an integrated RUSLE2/WEPS model to incorporate six different regime choices, covering management, harvest and conservation, into a simple profit maximization model to show these tradeoffs.


Potential Significance Of Photoexcited No2 On Global Air Quality With The Nmmb/Bsc Chemical Transport Model, O. Jorba, D. Dabdub, Christopher S. Blaszczak-Boxe, C. Pérez, Z. Janjic, J. M. Baldasano, M. Spada, A. Badia, M. Gonçalves Jul 2012

Potential Significance Of Photoexcited No2 On Global Air Quality With The Nmmb/Bsc Chemical Transport Model, O. Jorba, D. Dabdub, Christopher S. Blaszczak-Boxe, C. Pérez, Z. Janjic, J. M. Baldasano, M. Spada, A. Badia, M. Gonçalves

Publications and Research

Atmospheric chemists have recently focused on the relevance of the NO2* + H2O → OH + HONO reaction to local air quality. This chemistry has been considered not relevant for the troposphere from known reaction rates until nowadays. New experiments suggested a rate constant of 1.7 × 10−13 cm3 molecule−1 s−1, which is an order of magnitude faster than the previously estimated upper limit of 1.2 × 10−14 cm3 molecule−1 s−1, determined by Crowley and Carl (1997). Using the new global model, NMMB/BSC Chemical Transport Model (NMMB/BSC-CTM), simulations are presented that assess the potential significance of this chemistry on global …


Joint Diagonalization Applied To The Detection And Discrimination Of Unexploded Ordnance, Fridon Shubitidze, Juan Pablo Fernández, Irma Shamatava, Benjamin Barrowes, Kevin O’Neill Jul 2012

Joint Diagonalization Applied To The Detection And Discrimination Of Unexploded Ordnance, Fridon Shubitidze, Juan Pablo Fernández, Irma Shamatava, Benjamin Barrowes, Kevin O’Neill

Dartmouth Scholarship

Efforts to discriminate buried unexploded ordnance from harmless surrounding clutter are often hampered by the uncertainty in the number of buried targets that produce a given detected signal. We present a technique that helps determine that number with no need for data inversion. The procedure is based on the joint diagonalization of a set of multistatic response (MSR) matrices measured at different time gates by a time-domain electromagnetic induction sensor. In particular, we consider the Naval Research Laboratory’s Time-Domain Electromagnetic Multisensor Towed Array Detection System (TEMTADS), which consists of a 5×5 square grid of concentric transmitter/receiver pairs. The diagonalization process …


The Influence Of Non-Equilibrium Pressure On Rotating Flows, Irfan Rashid Zardadkhan Jul 2012

The Influence Of Non-Equilibrium Pressure On Rotating Flows, Irfan Rashid Zardadkhan

Mechanical & Aerospace Engineering Theses & Dissertations

This study was undertaken to investigate the influence of pressure relaxation on steady, incompressible flows with strong streamline curvature. In the early part of this dissertation research, the significance of non-equilibrium pressure forces in controlling the structure of a steady, two dimensional axial vortex was demonstrated. In order to extend the study of pressure relaxation influences on more complex rotating flows, this dissertation has examined other rotating flow features that can be associated with hurricanes, tornadoes and dust devils. To model these flows, modified boundary layer equations were developed for a fluid column rotating near a solid plane including the …


Observations Of Localised Effects Of The Busselton Compensating Basins On Surface Water, Groundwater And Soil Salinity, D L. Bennett, Richard J. George Dr Jun 2012

Observations Of Localised Effects Of The Busselton Compensating Basins On Surface Water, Groundwater And Soil Salinity, D L. Bennett, Richard J. George Dr

Resource management technical reports

Between 2001 and 2009 the Water Corporation constructed three flood-compensating basins on farmland in the Vasse and Sabina river catchments, upstream of in the city of Busselton. The basins are designed to reduce the risk of flooding in urban areas of Busselton by temporarily storing and then regulating runoff during flood events. This report fulfils the reporting requirements of a contract between the Water Corporation and the Department of Agriculture and Food. Data relating to the local groundwater and surface-water dynamics, salinity, nutrients and pH, plus changes to shallow and deep-soil salinity (from repeat ground-based electromagnetic induction [EM] surveying), was …


Estimating Land Surface Temperature Using A Thermal Sharpening Technique, Yitong Jiang, Qihao Weng May 2012

Estimating Land Surface Temperature Using A Thermal Sharpening Technique, Yitong Jiang, Qihao Weng

Symposium 2012

No abstract provided.


Dynamics Of Land Use/Land Cover Changes And Its Implication On Food Security In Anyigba, North Central, Nigeria, Tokula E. Arome, Sunday P. Ejaro (Phd) May 2012

Dynamics Of Land Use/Land Cover Changes And Its Implication On Food Security In Anyigba, North Central, Nigeria, Tokula E. Arome, Sunday P. Ejaro (Phd)

Confluence Journal Environmental Studies (CJES), Kogi State University, Nigeria

This study assessed land use/land cover changes and its effect on Agricultural land in Anyigba. The objectives were to identify and delineate different land use / land cover categories, assess the rate of change that occurred and examine the impact of land use/land cover change on food security using satellite remote sensing data collected at three different years (1987 Land sat TM, 2001 Land Sat TM and 2011 Land Sat ETM). The study utilized GIS software such as Idrisi Andes academic and ArcGIS 9.3. The study area covers approximately 31.8km2, and four major land use/cover classes were utilized (built up, …


Evaluation Of Hydraulic Conductivity Of Non Aqueous Phase Liquids In Partially Saturated Soils, Chijioke Ekeleme Akamiro Apr 2012

Evaluation Of Hydraulic Conductivity Of Non Aqueous Phase Liquids In Partially Saturated Soils, Chijioke Ekeleme Akamiro

Civil & Environmental Engineering Theses & Dissertations

This study seeks to investigate a problem of predicting the hydraulic conductivity of NAPLs in partially saturated soils and to relate the hydraulic conductivity to basic soil parameters that are either easy to determine or are in wide use. To evaluate hydraulic conductivity in partially saturated soils, previous researchers have focused on flow geometry, soil and chemical properties, etc. used in CHEMFLO program by Nofziger et al., (1989) and saturation equations by such authors as Van Genutchen (1980) and Brooks and Corey (1964). Among those, the soil-water characteristic curve (SWCC) is the most widely used constitutive relations for unsaturated soils …


Bioretention: Evaluating Their Effectiveness For Improving Water Quality In New England Urban Environments, Mary Dehais Mar 2012

Bioretention: Evaluating Their Effectiveness For Improving Water Quality In New England Urban Environments, Mary Dehais

Mary Dehais

Nonpoint source (NPS) pollution is one of the leading causes of water quality problems in the United States. Bioretention has become one of the more frequently used stormwater management practices for addressing NPS pollution in urbanized watersheds in New England. Yet despite increased acceptance, bioretention is not widely practiced. This study explores and evaluates the efficacy of bioretention for protecting urban water quality. This research found that numerous monitoring methods are used by researchers and industry experts to assess the effectiveness of stormwater best management practices (BMPs) and low impact development (LID) practices that include bioretention. The two most common …


Real-Time Change And Damage Detection Of Landslides And Other Earth Movements Threatening Public Infrastructure, Michael J. Olsen, Shawn Butcher, Evon P. Silvia Mar 2012

Real-Time Change And Damage Detection Of Landslides And Other Earth Movements Threatening Public Infrastructure, Michael J. Olsen, Shawn Butcher, Evon P. Silvia

TREC Final Reports

Geologic hazards such as coastal erosion, landslides, seismic loading, etc. constantly threaten public highway construction and maintenance. Repeat surveys using terrestrial laser scanning (TLS, ground-based LiDAR) enable rapid 3D data acquisition to map, see, analyze, and understand the processes generating such problems. Previously, change detection and analysis between scan surveys was conducted during post-processing upon return to the office, instead of while collecting data in the field. Change detection in the field improves the effectiveness and efficiency of the field investigation. We have developed a new algorithm that quickly geo-references scans upon field acquisition and simultaneously performs change detection by …


Global Monthly Water Scarcity: Blue Water Footprints Versus Blue Water Availability, Arjen Y. Hoekstra, Mesfin Mekonnen, Ashok K. Chapagain, Ruth E. Mathews, Brian D. Richter Feb 2012

Global Monthly Water Scarcity: Blue Water Footprints Versus Blue Water Availability, Arjen Y. Hoekstra, Mesfin Mekonnen, Ashok K. Chapagain, Ruth E. Mathews, Brian D. Richter

Daugherty Water for Food Global Institute: Faculty Publications

Freshwater scarcity is a growing concern, placing considerable importance on the accuracy of indicators used to characterize and map water scarcity worldwide. We improve upon past efforts by using estimates of blue water footprints (consumptive use of ground- and surface water flows) rather than water withdrawals, accounting for the flows needed to sustain critical ecological functions and by considering monthly rather than annual values. We analyzed 405 river basins for the period 1996–2005. In 201 basins with 2.67 billion inhabitants there was severe water scarcity during at least one month of the year. The ecological and economic consequences of increasing …


The Water Footprint Of Humanity, Arjen Y. Hoekstra, Mesfin Mekonnen Feb 2012

The Water Footprint Of Humanity, Arjen Y. Hoekstra, Mesfin Mekonnen

Daugherty Water for Food Global Institute: Faculty Publications

This study quantifies and maps the water footprint (WF) of humanity at a high spatial resolution. It reports on consumptive use of rainwater (green WF) and ground and surface water (blue WF) and volumes of water polluted (gray WF). Water footprints are estimated per nation from both a production and consumption perspective. International virtual water flows are estimated based on trade in agricultural and industrial commodities. The global annual average WF in the period 1996–2005 was 9,087 Gm3 ∕y (74% green, 11% blue, 15% gray). Agricultural production contributes 92%. About one-fifth of the global WF relates to production for export. …


Exploring The Effects Of Aperture Size, Aperture Variability And Matrix Properties On Biocolloid Retention In A Single, Saturated Fracture, Margaret Burke Jan 2012

Exploring The Effects Of Aperture Size, Aperture Variability And Matrix Properties On Biocolloid Retention In A Single, Saturated Fracture, Margaret Burke

Sarah E Dickson

No abstract provided.


Slides: Unconventional Gas And Oil – Potential Air Emissions, John Imse Jan 2012

Slides: Unconventional Gas And Oil – Potential Air Emissions, John Imse

Air Quality Impacts from Oil and Gas Development (January 27)

Presenter: John Imse, Hydrogeologist, ENVIRON International Corporation presents an overview of the current methods for developing a shale play and the typical site operations

10 slides


Slides: Air Monitoring And Litigation Update, John Jacus Jan 2012

Slides: Air Monitoring And Litigation Update, John Jacus

Air Quality Impacts from Oil and Gas Development (January 27)

Presenter: John Jacus, Partner, Davis Graham & Stubbs LLP, reviews recent litigation aimed at oil and gas development activities with respect to air emissions impacts, and also several recent and ongoing studies and ambient monitoring efforts focused upon air emissions from oil and gas activities

23 slides


Slides: Air Quality - Oil And Gas Development, Paul R. Tourangeau Jan 2012

Slides: Air Quality - Oil And Gas Development, Paul R. Tourangeau

Air Quality Impacts from Oil and Gas Development (January 27)

Presenter: Paul Tourangeau, Assistant General Counsel, DCP Midstream, LP and former Director, Colorado Air Pollution Control Division, addresses regulatory requirements and policies related to air emissions from the oil and gas sector, including recent and current initiatives at the state and federal level

8 slides


Slides: Hydrofracking: Air Issues And Community Exposure, Debra A. Kaden Jan 2012

Slides: Hydrofracking: Air Issues And Community Exposure, Debra A. Kaden

Air Quality Impacts from Oil and Gas Development (January 27)

Presenter: Debra Kaden, Ph.D., Toxicologist, ENVIRON International Corporation, discusses air concentrations of chemicals of potential health concern surrounding oil and gas development activities, as well as temporal and spatial patterns of these chemicals in the ambient environment. Such information is necessary to evaluate possible health impacts of the drilling process on air in surrounding communities.

19 slides


Agenda: Air Quality Impacts From Oil And Gas Development, University Of Colorado Boulder. Natural Resources Law Center Jan 2012

Agenda: Air Quality Impacts From Oil And Gas Development, University Of Colorado Boulder. Natural Resources Law Center

Air Quality Impacts from Oil and Gas Development (January 27)

Oil and gas development and hydraulic fracturing have received enormous attention over the past few years, and most of that attention has focused on the potential impacts of such development on water quality. However, the potential impacts on air quality from oil and gas development have received far less public and media attention and discussion. This two-hour program will assess the current scientific knowledge, regulatory requirements and policies regarding the impacts on air quality from oil and gas development and will address current initiatives at the state and national levels to further regulate and control those impacts.