Influence Of Deposition Temperature On Properties Of Multilayered Gallium Doped Zinc Oxide Films Prepared By Dc Magnetron Sputtering Technique,
2020
Department of Physics, CoNAS, University of Dar es Salaam
Influence Of Deposition Temperature On Properties Of Multilayered Gallium Doped Zinc Oxide Films Prepared By Dc Magnetron Sputtering Technique, Elisante Maloda, Anayesu Malisa
Tanzania Journal of Science
Multilayered transparent conducting films based on ZnO: Ga were deposited onto glass substrate by DC magnetron sputtering technique. The films were prepared from alloy (Zn: Ga) and ceramic (ZnO: Ga) targets with gallium composition of 3 at% and 4 at%, respectively. Crystal structure and phase analysis were measured using X-ray diffractometer (XRD). The XRD structural analysis results indicated that all multilayered films were polycrystalline with (002) orientation slightly shifted of diffracting angles due to gallium dopant concentrations as increase in the deposition temperatures. The films were hexagonal wurtzite structure, having preferred growth orientation in c-axis perpendicular to the substrate surface. …
Projected Surface Water For Fruit And Vegetable Irrigation Under A Changing Climate In The Us,
2020
University of Arkansas, Fayetteville
Projected Surface Water For Fruit And Vegetable Irrigation Under A Changing Climate In The Us, Marty Matlock, Greg Thoma, Kieu Ngoc Le, Eric Cummings, Zach Morgan, Andrew Shaw
Water Systems
Increasing greenhouse gas concentrations in the atmosphere, resulting in climate impacts, are raising concerns over the hydrologic cycle and its effects upon agricultural productivity. If rainfall patterns change, meeting an increased demand for fruits and vegetables will pose a challenge for domestic production regions in the United States (U.S.). Information on potential water supply scarcity in the current production regions provides decision makers with critical information for risk mitigation for future production. We used a hydrologic balance-based model of historic and future water availability to evaluate risk of available irrigation water to support major fruit and vegetable production the US. …
Shallow-Water Coral Communities Support The Separation Of Marine Ecoregions On The West-Central Florida Gulf Coast,
2020
Nova Southeastern University
Shallow-Water Coral Communities Support The Separation Of Marine Ecoregions On The West-Central Florida Gulf Coast, Brian K. Walker, Shelby Eagan, Cory Ames, Sandra Brooke, Sean Keenan, Rene Baumstark
Marine & Environmental Sciences Faculty Articles
Florida’s west coast is a 170,000 km2 bedrock shelf (west Florida shelf, WFS) comprised of north-south discontinuous carbonate outcroppings extending more than 200 km from the intertidal zone to a depth of 200 m. These outcrops support diverse benthic communities, which contribute to a multi-billion dollar recreational and commercial fishing industry, yet only about 5% of their extent has been studied in detail. Benthic communities shift over a 6.5° geographic range, but the locations of these shifts are not well-defined. Previous studies have suggested a break in biogeographic regions at Tampa Bay, south at Cape Romano, and north at …
Studies Of Quaternary Depositional Systems Of The Coastal Plain And Inner Continental Shelf Along The Georgia Bight: South Carolina And Georgia, U.S.A.,
2020
Coastal Carolina University
Studies Of Quaternary Depositional Systems Of The Coastal Plain And Inner Continental Shelf Along The Georgia Bight: South Carolina And Georgia, U.S.A., Joshua H. Long
Electronic Theses and Dissertations
The Quaternary stratigraphy of the continental shelf offshore of South Carolina consists of stratigraphic units deposited in coastal plain, shallow marine, and shelfal environments bound by composite erosional surfaces that developed in response to numerous glacioeustatic cycles and overprinted by regional uplift. These units are commonly distributed laterally rather than stacked vertically, a function of the long-term, low shelf gradient and the resulting lack of accommodation. This study integrates high-resolution geological and geophysical data sets acquired offshore and onshore with existing data onshore into a comprehensive conceptual model describing the Quaternary geologic evolution of the coastal plain and continental shelf …
Long Lived Second Mode Internal Solitary Waves In The Andaman Sea,
2020
University of Porto
Long Lived Second Mode Internal Solitary Waves In The Andaman Sea, J.M. Magalhaes, J.C.B. Da Silva, Maarten C. Buijsman
Faculty Publications
Internal waves are density oscillations propagating along the ocean’s inner stratification, which are now acknowledged as a key constituent of the ocean’s dynamics. They usually result from barotropic tides, which flow over bottom topography, causing density oscillations to propagate along the pycnocline with a tidal frequency (i.e. internal tides). These large-scale waves propagate away from their forcing bathymetry and frequently disintegrate into nonlinear short-scale (higher-frequency) internal wave packets. Typically, short-scale internal wave observations in the ocean are associated with vertical structures (in the water column) of the lowest fundamental mode. Higher vertical modes have recently been documented as well, but …
Investigating The Isotope Signatures Of Dissolved Iron In The Southern Atlantic Ocean,
2020
University of South Florida
Investigating The Isotope Signatures Of Dissolved Iron In The Southern Atlantic Ocean, Brent A. Summers
USF Tampa Graduate Theses and Dissertations
Iron (Fe), used as a cofactor in nitrogen fixation and photosynthesis by oceanic microorganisms, has extremely low dissolved concentrations in the surface ocean, leading to widespread limitation of phytoplankton growth. Dissolved Fe isotope ratios (δ56Fe) have been shown to be useful in helping to quantify the sources and cycling of Fe in the oceans if Fe source signatures and fractionation processes are well understood. Here, this thesis presents data from GEOTRACES section GA10W, and investigate the isotopic signature of sediment-derived dissolved Fe from the South Atlantic margins. My results show that there are both shallow (δ56Fe of -0.2‰) and deep …
Climate Change Impacts The Subsurface Transport Of Atrazine And Estrone Originating From Agricultural Production Activities,
2020
University of Nebraska-Lincoln
Climate Change Impacts The Subsurface Transport Of Atrazine And Estrone Originating From Agricultural Production Activities, Renys Enrique Barrios, Simin Akbariyeh, Chuyang Liu, Khalid Muzamil Gani, Margarita T. Kovalchuk, Xu Li, Yusong Li, Daniel D. Snow, Zhenghong Tang, John Gates, Shannon L. Bartelt-Hunt
Nebraska Water Center: Faculty Publications
Climate change will impact soil properties such as soil moisture, organic carbon and temperature and changes in these properties will influence the sorption, biodegradation and leaching of trace organic contaminants to groundwater. In this study, we conducted a modeling case study to evaluate atrazine and estrone transport in the subsurface under current and future climate conditions at a field site in central Nebraska. According to the modeling results, in the future, enhanced evapotranspiration and increased average air temperature may cause drier soil conditions, which consequently reduces the biodegradation of atrazine and estrone in the water phase. On the other hand, …
Odu, Elizabeth River Project Announce Collaborative Initiative,
2020
Old Dominion University
Odu, Elizabeth River Project Announce Collaborative Initiative, Joe Garvey
News Items
No abstract provided.
Long-Term Ndvi And Recent Vegetation Cover Profiles Of Major Offshore Island Nesting Sites Of Sea Turtles In Saudi Waters Of The Northern Arabian Gulf,
2020
King Fahd University of Petroleum and Minerals
Long-Term Ndvi And Recent Vegetation Cover Profiles Of Major Offshore Island Nesting Sites Of Sea Turtles In Saudi Waters Of The Northern Arabian Gulf, Rommel H. Maneja, Jeffrey D. Miller, Wenzhao Li, Hesham El-Askary, Ace Vincent B. Flandez, Joshua J. Dagoy, Joselito Francis A. Alcaria, Abdullajid U. Basali, Khaled A. Al-Abdulkader, Ronald A. Loughland, Mohamed A. Qurban
Mathematics, Physics, and Computer Science Faculty Articles and Research
Vegetation is an important ecological component of offshore islands in the Arabian Gulf (AG), which maintains long-term resilience of these islands. This is achieved by influencing sediment retention and moisture acquisition via condensation during periods of high humidity and by providing a variety of microhabitats for island fauna. The resilience of offshore islands’ ecosystems in the Saudi waters is important because they host the largest number of nesting hawksbill and green turtles in the AG. This study defines the characteristics and the long-term trends in vegetation cover of the offshore islands used by sea turtles as nesting grounds in the …
Vertebrates On The Brink As Indicators Of Biological Annihilation And The Sixth Mass Extinction,
2020
Universidad Nacional Autónoma de México
Vertebrates On The Brink As Indicators Of Biological Annihilation And The Sixth Mass Extinction, Gerardo Ceballos, Paul R. Ehrlich, Peter H. Raven
Harold W. Manter Laboratory of Parasitology: Library Materials
The ongoing sixth mass species extinction is the result of the destruction of component populations leading to eventual extirpation of entire species. Populations and species extinctions have severe implications for society through the degradation of ecosystem services. Here we assess the extinction crisis from a different perspective. We examine 29,400 species of terrestrial vertebrates, and determine which are on the brink of extinction because they have fewer than 1,000 individuals. There are 515 species on the brink (1.7% of the evaluated vertebrates). Around 94% of the populations of 77 mammal and bird species on the brink have been lost in …
Impacts Of Two Different Types Of El Niño On The Thermal Variability In The South China Sea,
2020
National Museum of Marine Science & Technology, Research & Collection Division, Keelung, Taiwan, R.O.C
Impacts Of Two Different Types Of El Niño On The Thermal Variability In The South China Sea, Chun-Yi Lin, Yung-Hsiang Lee, Feng-Chun Su
Journal of Marine Science and Technology–Taiwan
The El Niño-Southern Oscillation (ENSO) has been classified into two types: the Central-Pacific (CP) type and the Eastern-Pacific (EP) type. To further understand the impacts of the two types of ENSO upon the thermal variability in the South China Sea (SCS), the reanalysis dataset dealing with the parameters of sea surface temperature (SST), surface air temperature, sea surface wind, precipitation, and sea-level pressure are analyzed herein via the regression-empirical orthogonal function. In addition, the Western Pacific Warm Pool (WPWP), the largest warm water mass in the world’s oceans, is known to have a strong impact upon the climate of its …
Determination Of Volatile Organic Compounds At A Marine Terminal In United States Using In-Borehole Gas Monitoring,
2020
Department of Physics/Geology/Geophysics, Faculty of Science, Alex Ekwueme Federal University, Ndufu-Alike Ikwo (AE-FUNAI), Ebonyi State, Nigeria.
Determination Of Volatile Organic Compounds At A Marine Terminal In United States Using In-Borehole Gas Monitoring, A. N. Nwachukwu, C. U. Uwa, K. E. Nwagu, B. E. Ephraim
Journal of Marine Science and Technology–Taiwan
A time-series study was conducted to determine both the aggregate and specific Volatile Organic Compounds (VOCs) concentrations at a Marine Terminal. An in-situ aggregate data of VOC concentrations and some environmental parameters were logged by means of an in-borehole gas monitor called Gasclam (Ion Science, UK). A Tenax TA sorbent tube incorporated into and to work in parallel with the Gasclam was used to adsorb bulk concentrations of VOCs and subsequently desorbed (for characterization) using Thermal Desorption/Gas Chromatography-Mass Spectroscopy (TD/GC-MS) technique. The result shows aggregate VOC concentrations of 31385 ppm and 17140 ppm in wells I and II respectively over …
Great Basin Paleoclimate And Aridity Linked To Artic Warming And Tropical Pacific Sea Surface Temperature,
2020
University of Nevada, Las Vegas
Great Basin Paleoclimate And Aridity Linked To Artic Warming And Tropical Pacific Sea Surface Temperature, Matthew S. Lachniet, Yemane Asmerom, Victor Polyak, Rhawn Denniston
Geoscience Faculty Research
The arid southwestern United States is susceptible to sustained droughts that impact water resources and economic activity for millions of residents. Previous work has not systematically investigated the structure, timing, and possible forcings of Holocene Great Basin sub‐orbital hydroclimate changes, impeding our ability to understand the potential future controls on Southwestern aridity. The objective of this paper is to constrain the potential forcings on Holocene aridity and temperature, via comparison of new high‐resolution speleothem data, an Aridity Index synthesizing hydroclimate records, and linkages of Southwestern paleoclimate to other regions. The high‐resolution data from Leviathan Cave provide a paleoclimate record since …
Seasonal Transport Of Dissolved Inorganic Carbon And Total Alkalinity Across The Louisiana Shelf,
2020
Louisiana State University and Agricultural and Mechanical College
Seasonal Transport Of Dissolved Inorganic Carbon And Total Alkalinity Across The Louisiana Shelf, Michelle M. Anderson
LSU Master's Theses
Rivers and wetlands are a major source of terrestrial derived carbon for coastal ocean margins. Unfortunately, Louisiana’s wetlands are threatened by ongoing high rates of erosion, deterioration, and unprecedented rates of river water discharge that changes seasonally, leading to a net loss of terrestrial carbon into the northern Gulf of Mexico (nGOM). There exists a current lack of understanding about the distribution of dissolved inorganic carbon (DIC) and total alkalinity (TAlk) within the shallowest regions of the Louisiana shelf. Even less is known about how the transport of DIC alters seasonally with changes in river outflow and shelf currents. Quantifying …
Microplastics In Mississippi River Fishes: A Watershed Approach,
2020
Louisiana State University
Microplastics In Mississippi River Fishes: A Watershed Approach, Ahmed Gad
LSU Master's Theses
Microplastics are plastic particles less than 5mm that come from different sources, such as industrial products, cosmetics, and the breakdown of the macroplastics. Microplastics derive from terrestrial sources but concentrate in flowing freshwaters where they may enter aquatic food webs. The northern Gulf of Mexico has shown very high microplastic concentrations, which are assumed to be sourced from the Mississippi River and its watershed. This study seeks to study microplastics in fish in the Mississippi River and the Gulf of Mexico. Fish stomachs and intestines from fish underwent chemical digestion, filtration, and microplastics identification and enumeration through FT-IR spectrometry. Chapter …
Author Correction: Estimating Global Mean Sea-Level Rise And Its Uncertainties By 2100 And 2300 From An Expert Survey,
2020
Rowan University
Author Correction: Estimating Global Mean Sea-Level Rise And Its Uncertainties By 2100 And 2300 From An Expert Survey, Benjamin P. Horton, Nicole S. Khan, Niamh Cahill, Janice S.H. Lee, Timothy A. Shaw, Andra J. Garner, Andrew C. Kemp, Simon E. Engelhart, Stefan Rahmstorf
School of Earth & Environment Departmental Research
Correction to: NPJ Climate and Atmospheric Science https://doi.org/10.1038/s41612-020-0121-5, published online 08 May 2020
Sediment Transport And Geomorphological Evolution In The Transgressive Ship Shoal, Louisiana: Insights From Geophysical Observation, Modeling, And Machine Learning Studies,
2020
Louisiana State University
Sediment Transport And Geomorphological Evolution In The Transgressive Ship Shoal, Louisiana: Insights From Geophysical Observation, Modeling, And Machine Learning Studies, Haoran Liu
LSU Doctoral Dissertations
Ship Shoal has been a high-priority target sand resource for dredging activities to restore the eroding barrier islands in Louisiana, USA. Many studies have been performed in Ship Shoal in recent decades, but our knowledge of temporal and spatial variations of sediment transport and post-dredge morphology is still limited. The objectives of this dissertation are to explore the sediment infilling process, the spatial and temporal evolution of the morphology of dredge pits near and on Ship Shoal by using multiple methods. Scientific methods used in this study include (a) geophysical observation using bathymetry, side-scan and subbottom technique, (b) sediment transport …
Combined Use Of Sentinel‐1 Sar And Landsat
Sensors Products For Residual Soil Moisture
Retrieval Over Agricultural Fields In The Upper Blue
Nile Basin, Ethiopia,
2020
Ethioppian Space Science and Technology Institute
Combined Use Of Sentinel‐1 Sar And Landsat Sensors Products For Residual Soil Moisture Retrieval Over Agricultural Fields In The Upper Blue Nile Basin, Ethiopia, Getachew Ayehu, Tsegaye Tadesse, Berhan Gessesse, Yibeltal Yigrem, Assefa M. Melesse
National Drought Mitigation Center: Faculty Publications
The objective of this paper is to investigate the potential of sentinel‐1 SAR sensor products and the contribution of soil roughness parameters to estimate volumetric residual soil moisture (RSM) in the Upper Blue Nile (UBN) basin, Ethiopia. The backscatter contribution of crop residue water content was estimated using Landsat sensor product and the water cloud model (WCM). The surface roughness parameters were estimated from the Oh and Baghdadi models. A feed‐forward artificial neural network (ANN) method was tested for its potential to translate SAR backscattering and surface roughness input variables to RSM values. The model was trained for three inversion …
Effectiveness Of Topical Antibiotics In Treating Corals Affected By Stony Coral Tissue Loss Disease,
2020
Nova Southeastern University
Effectiveness Of Topical Antibiotics In Treating Corals Affected By Stony Coral Tissue Loss Disease, Karen L. Neely, Kevin A. Macaulay, Emily K. Hower, Michelle A. Dobler
Marine & Environmental Sciences Faculty Articles
Since 2014, Stony Coral Tissue Loss Disease (SCTLD) has led to mass mortality of the majority of hard coral species on the Florida Reef Tract. Following the successful treatment of SCTLD lesions on laboratory corals using water dosed with antibiotics, two topical pastes were developed as vehicles to directly apply antibiotic treatments to wild corals. These pastes were tested as placebos and with additions of amoxicillin on active SCTLD lesions on multiple coral species. The effectiveness of the pastes without antibiotics (placebo treatments) was 4% and 9%, no different from untreated controls. Adding amoxicillin to both pastes significantly increased effectiveness …
Pacific Decadal Oscillation Remotely Forced By The Equatorial Pacific And The Atlantic Oceans,
2020
Utah State University
Pacific Decadal Oscillation Remotely Forced By The Equatorial Pacific And The Atlantic Oceans, Zachary F. Johnson, Yoshimitsu Chikamoto, Shih-Yu Simon Wang, Michael J. Mcphaden, Takashi Mochizuki
Plants, Soils, and Climate Faculty Publications
The Pacific Decadal Oscillation (PDO), the leading mode of Pacific decadal sea surface temperature variability, arises mainly from combinations of regional air-sea interaction within the North Pacific Ocean and remote forcing, such as from the tropical Pacific and the Atlantic. Because of such a combination of mechanisms, a question remains as to how much PDO variability originates from these regions. To better understand PDO variability, the equatorial Pacific and the Atlantic impacts on the PDO are examined using several 3-dimensional partial ocean data assimilation experiments conducted with two global climate models: the CESM1.0 and MIROC3.2m. In these partial assimilation experiments, …
