Physical Sciences and Mathematics Commons^™

Double Acting Liberation Of Ni And Co In The Pre-Treatment Process To Increase Recovery Of Nickel From Low-Grade Nickel Laterite, Eni Febriana, Muhamad Irham Mulyadi, Wahyu Mayangsari, Januar Irawan, Iwan Setiawan, Ahmad Maksum, Florentinus Firdiyono, Soesaptri Oediyani, Agus Budi Prasetyo, Johny W. Soedarsono

Journal of Sustainable Mining

This study highlights the effectiveness of employing double-acting liberation to release Ni and Co from the complex phases of the low-grade nickel laterite. It includes the addition of concentrated sulphuric acid and NaF as well as the heat treatment prior to roasting and leaching processes to improve the destruction of the complex phases contained. The finding describes that dehydration of iron sulfate and decomposition of the lizardite at a lower temperature, 270°C, were occurred in the pre-treatment process, followed by hematite formation in the roasting process. It subsequently accelerated Ni and Co extraction in the pregnant solution and omitted Fe …

Improving Accessibility And Understanding: Studying The Impact Of Human Activities And Dam Removals On Anadromous Fish Species In The Pacific Northwest, Adia F. Bennett

Scripps Senior Theses

Human activities in North American watersheds have significantly impacted anadromous fish, causing some species of salmon and steelhead to become threatened and endangered. These fish hold ecological, cultural, and economic importance, yet factors such as habitat destruction, overfishing, pollution, climate change, and hydroelectric dams continue to degrade populations. Dams are particularly harmful to anadromous fish, sparking a recent movement advocating for dam removals. This study uses NOAA’s 2022 Biological Viability Assessment to examine the response of anadromous fish to recent dam removals in the Pacific Northwest. Four populations were selected to analyze due to their interaction with sites that had …

Ohio Recovery Housing: Resident Risk And Outcomes Assessment, Elyjiah Potter, Bivin Sadler

SMU Data Science Review

Addiction and substance abuse disorder is a significant problem in the United States. Over the past two decades, the United States has faced a boom in substance abuse, which has resulted in an increase in death and disruption of families across the nation. The State of Ohio has been particularly hard hit by the crisis, with overdose rates nearly doubling the national average. Established in the mid 1970’s Sober Living Housing is an alcohol and substance use recovery model emphasizing personal responsibility, sober living, and community support. This model has been adopted by the Ohio Recovery Housing organization, which seeks …

Studies On Rehabilitation And Recovery Of Degraded Shrub Rangeland In Central China, G. Xiao

IGC Proceedings (1993-2023)

Central China used to be the most important region for animal production, but over-grazing, over- cultivation and deforestation all resulted in a decline in shrub rangeland productivity as well as increasing soil degradation (JiZhou, 1989). Soil erosion, salinisation and desertification have become serious problems. The productivity of shrub rangeland decreased from 3,000~4,000kg/ha to 1,500~2,000kg/ha from the 1960s to the 1990s (Wei, 1991). Since 1990, measures have been taken to solve this problem with promising results.

The Economic Value Of Sea Otters And Recreational Tourism In A California Estuary, Jessica A. Fujii, Charles S. Colgan, Anthony Castelletto, Michelle M. Staedler, Amy G. Wolfrum, Kyle S. Van Houtan

Journal of Ocean and Coastal Economics

The recovery of marine megafauna can lead to improved ecosystem function and services, but not all stakeholders may benefit equally. Quantifying the local economic value of a species’ presence may appeal to broader range of stakeholders when developing conservation strategies. This study aims to examine the economic effect recreational activities can have on a local region, and to determine what role the presence of southern sea otters (Enhydra lutris nereis) had on the value visitors placed on the visit and the area’s preservation. We surveyed visitors to Elkhorn Slough, a small estuary in California known for diverse wildlife, …

Post Wildfire Vegetation Response To The Wildland-Urban Interface: A Case Study Of The Station Fire, Angelo C. De Guzman, Raju Bista, Parveen K. Chhetri

CSU Journal of Sustainability and Climate Change

In the past, wildfires served as a method for mother nature to promote biodiversity and to help maintain a functioning ecosystem. However, climate change alters the fire regime, significantly impacting vegetation recovery. Human disturbances and increased land use and land cover heighten vegetation disruption and abundance after a fire. Wildland-urban interface (WUI) – the region where the vegetation intermingles with the roads, houses, and human-made structures – threatens vegetation and the human population. Overall vegetation recovery after the Station Fire of 2009 spread through the San Gabriel Mountains, Los Angeles County was observed using Digital Elevation Model (DEM), Normalized Difference …

Opportunities And Challenges From Major Disasters Lessons Learned Of Long-Term Recovery Group Members, Eduardo E. Landaeta

Graduate Program in International Studies Theses & Dissertations

Natural hazards caused by the alteration of weather patterns expose populations at risk, with an outcome of economic loss, property damage, personal injury, and loss of life. The unpredictability of disasters is a topic of concern to most governments. Disaster policies need more attention in aligning mitigation opportunities with disaster housing recovery (DHR). The effect of flooding, which primarily impacts housing in coastal areas, is one of the most serious issues associated with natural hazard. Flooding has a variety of causes and implications, especially for vulnerable populations who are exposed to it. DHR is complex, involving the need for effective …

Exploring The Characterization, Liberation And Flotation Response Of A Nigerian Low-Grade Copper Ore, Willie Nheta, Omoyemi O. Ola-Omole

Journal of Sustainable Mining

This study explores the characterization, liberation and flotation response of low-grade copper ore from Anka area, Zamfara state Nigeria. The ore was crushed, milled and sieved in accordance with BS 410 standard. It was characterized with XRD, XRF, SEM-EDS and AAS. Froth flotation was carried out with varying %solids, pH, retention time and collector dosages using SEX and sodium oleate. Particle size distribution of the ore shows its economic liberation between -150 and +106 µm while 80% passing corresponds to 175.7 µm using the Gaudin Schuhmann equation. However, according to metallurgical balance calculation, 63 µm proved to have the highest …

The Ability Of Ruppia Polycarpa To Regenerate From Seed Depends On Seasonal Porewater Salinity Dynamics And Declining Winter Rainfall Could Delay Recruitment, Chanelle L. Webster, Paul S. Lavery, Simone Strydom, Jessica Billinghurst, Kathryn Mcmahon

Research outputs 2022 to 2026

For many plants, regeneration from seed is vital for population recovery. Climate change is modifying the global hydrological cycle and a primary factor controlling germination of marine plants: salinity. How altered salinity regimes, and especially altered porewater salinity regimes, will regulate early life history stages of estuarine seagrasses is poorly understood. Here, we quantified the porewater salinity dynamics in two ephemeral estuaries that are dominated by the cosmopolitan genus Ruppia. Seedbank, germlings (germinated seeds) and seedlings were found in salinities ranging from 5 to 110 over an annual cycle. To understand the germination ecology of the dominant species, Ruppia polycarpa, …

Elevation-Distributed Multistage Reverse Osmosis Desalination With Seawater Pumped Storage, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

A seawater reverse osmosis (RO) plant layout based on multistage RO with stages located at different elevations above sea level is described. The plant uses the weight of a seawater column from pumped storage as head pressure for RO (gravity-driven multistage RO) or to supplement high-pressure pumps used in RO (gravity-assisted multistage RO). The use of gravitational force reduces the specific energy for RO compared to using high-pressure pumps. By locating the RO stages at different elevations based on demand sites, the total specific energy consumption for RO and permeate transport to different elevations above sea level is reduced from …

Separation Efficiency Of Different Methods In Treatment Of A Low-Grade Iron Ore, Özgür Özcan

Bulletin of the Mineral Research and Exploration

In the present study, characterization and beneficiation tests were performed on an iron ore sample for the evaluation of separation efficiency (SE) of different methods. Results showed that the decrease in feed size fraction increases the SE irrespective of to beneficiation method. It was determined from the liberation analyses that the increase in SE values at finer size fractions is related with higher liberation. Calculated SE values revealed that operational parameters significantly affect the SE of all methods and the net forces acting on particles play an important role on SE of different size fractions. Mean SE of different size …

Benthic Community Dynamics And Stony Coral Demographics In Florida In Relation To Acute Disturbances And Chronic Pressures, Nicholas P. Jones

All HCAS Student Capstones, Theses, and Dissertations

The persistence of coral reef communities is threatened by a suite of pressures operating at varying spatial and temporal scales. In general, acute disturbances (short term stochastic events such as marine heatwaves or hurricanes) and chronic pressures, such as ocean warming, have caused the most significant changes to stony coral assemblages (order Scleractinia) and continue to impair recovery potential. Additionally, many coral reefs are subject to local chronic anthropogenic pressures resulting in poor water quality or sedimentation, which further impact stony corals and shape benthic community structure, particularly near urbanized coastlines. For the viability of communities on coral reefs, a …

The Dissolution And Recovery Of Critical Materials (Li2co3 And Uf6) From Ionic Liquid, Cassara Higgins

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lithium and uranium are critical materials in both the energy industry and for national security. Lithium is necessary for the next generation of batteries and 6Li is valuable for the production of tritium necessary for both fusion energy and to maintain our nuclear stockpiles. Uranium is a fuel source or precursor fuel source for commercially operating nuclear fission power. The monitoring of uranium hexafluoride (UF6) enrichment at foreign facilities is important for the monitoring of nuclear safeguards and enforcement of non-proliferation treaties. Recovery methods for lithium at the end of life of batteries are necessary to ensure abundance of the …

Porewater Salinity Influences Germination Of Ruppia Polycarpa In Variable Estuarine Habitats, Chanelle Webster

Research Datasets

Porewater salinity at different depth intervals during different months. Seed, germling and seedling density data in two estuaries and during different months. Seed germination, seedling establishment and growth under experimental conditions.

Overfishing Drives Over One-Third Of All Sharks And Rays Toward A Global Extinction Crisis, Nicholas K. Dulvy, Nathan Pacoureau, Cassandra L. Rigby, Riley A. Pollom, Rima W. Jabado, David A. Ebert, Brittany Finucci, Caroline M. Pollock, Jessica Cheok, Danielle H. Derrick, Katelyn B. Herman, C. Samantha Sherman, Wade J. Vanderwright, Julia M. Lawson, Rachel H.L. Walls, John K. Carlson, Patricia Charvet, Kinattumkara K. Bineesh, Daniel Fernando, Gina M. Ralph, Jay H. Matsushiba, Craig Hilton-Taylor, Sonja V. Fordham, Colin A. Simpfendorfer

Biological Sciences Faculty Publications

The scale and drivers of marine biodiversity loss are being revealed by the International Union for Conservation of Nature (IUCN) Red List assessment process. We present the first global reassessment of 1,199 species in Class Chondrichthyes-sharks, rays, and chimeras. The first global assessment (in 2014) concluded that one-quarter (24%) of species were threatened. Now, 391 (32.6%) species are threatened with extinction. When this percentage of threat is applied to Data Deficient species, more than one-third (37.5%) of chondrichthyans are estimated to be threatened, with much of this change resulting from new information. Three species are Critically Endangered (Possibly Extinct), representing …

Apparent Recovery Of Surface Applied Nitrogen Fertilizer By A Coastcross Pasture, A. C. Primavesi, O. Primavesi, L. A. Corrêa, H. Cantarella, A. G. Silva

IGC Proceedings (1993-2023)

Nitrogen recoveries from five levels of urea and ammonium nitrate surface-applied on coastcross pasture, grown on a dark red latosol (Hapludox), in São Carlos, SP, Brazil, under tropical altitude climate, were estimated. Significant differences occurred within periods (P < 0.05), depending on climatic conditions. Under adequate plant growth conditions, mean N recovery from urea was about 67%, sometimes reaching 80%, of that from ammonium nitrate. Recovery of ammonium nitrate varied from 45 to 68% of applied N.

Ocean Regime Shift Is Driving Collapse Of The North Atlantic Right Whale Population, Erin L. Meyer-Gutbrod, Charles H. Greene, Kimberley T.A. Davies, David G. Johns

Faculty Publications

Ocean warming linked to anthropogenic climate change is impacting the ecology of marine species around the world. In 2010, the Gulf of Maine and Scotian Shelf regions of the Northwest Atlantic underwent an unprecedented regime shift. Forced by climate-driven changes in the Gulf Stream, warm slope waters entered the region and created a less favorable foraging environment for the endangered North Atlantic right whale population. By mid-decade, right whales had shifted their late spring/summer foraging grounds from the Gulf of Maine and the western Scotian Shelf to the Gulf of St. Lawrence. The population also began exhibiting unusually high …

Improved Functional Outcome After Peripheral Nerve Stimulation Of The Impaired Forelimb Post-Stroke, Shih-Yen Tsai, Jennifer A. Schreiber, Natalie S. Adamczyk, Joanna Y. Wu, Son T. Ton, Ryan C. Hofler, James S. Walter, Timothy O'Brien, Gwendolyn Kartje-Tillotson, Russ P. Nockels

Mathematics and Statistics: Faculty Publications and Other Works

Lack of blood flow to the brain, i.e., ischemic stroke, results in loss of nerve cells and therefore loss of function in the effected brain regions. There is no effective treatment to improve lost function except restoring blood flow within the first several hours. Rehabilitation strategies are widely used with limited success. The purpose of this study was to examine the effect of electrical stimulation on the impaired upper extremity to improve functional recovery after stroke. We developed a rodent model using an electrode cuff implant onto a single peripheral nerve (median nerve) of the paretic forelimb and applied daily …

Mitochondria Exert Age-Divergent Effects On Recovery From Spinal Cord Injury, Andrew N. Stewart, Katelyn E. Mcfarlane, Hemendra J. Vekaria, William M. Bailey, Stacey A. Slone, Lauren A. Tranthem, Bei Zhang, Samir P. Patel, Patrick G. Sullivan, John C. Gensel

Physiology Faculty Publications

The extent that age-dependent mitochondrial dysfunction drives neurodegeneration is not well understood. This study tested the hypothesis that mitochondria contribute to spinal cord injury (SCI)-induced neurodegeneration in an age-dependent manner by using 2,4-dinitrophenol (DNP) to uncouple electron transport, thereby increasing cellular respiration and reducing reactive oxygen species (ROS) production. We directly compared the effects of graded DNP doses in 4- and 14-month-old (MO) SCI-mice and found DNP to have increased efficacy in mitochondria isolated from 14-MO animals. In vivo, all DNP doses significantly exacerbated 4-MO SCI neurodegeneration coincident with worsened recovery. In contrast, low DNP doses (1.0-mg/kg/day) improved tissue …

Fast And Pervasive Transcriptomic Resilience And Acclimation Of Extremely Heat-Tolerant Coral Holobionts From The Northern Red Sea, Romain Savary, Daniel J. Barshis, Christian R. Voolstra, Anny Cárdenas, Nicolas R. Evensen, Guilhem Banc-Prandi, Maoz Fine, Anders Meiborn

Biological Sciences Faculty Publications

Corals from the northern Red Sea and Gulf of Aqaba exhibit extreme thermal tolerance. To examine the underlying gene expression dynamics, we exposed Stylophora pistillata from the Gulf of Aqaba to short-term (hours) and long-term (weeks) heat stress with peak seawater temperatures ranging from their maximum monthly mean of 27 °C (baseline) to 29.5 °C, 32 °C, and 34.5 °C. Corals were sampled at the end of the heat stress as well as after a recovery period at baseline temperature. Changes in coral host and symbiotic algal gene expression were determined via RNA-sequencing (RNA-Seq). Shifts in coral microbiome composition were …

Evaluation Of The Fuel Cell Performances Of Tio2/Pan Electrospun Carbon-Based Electrodes, Sema Aslan

Turkish Journal of Chemistry

Electrocatalytic effect of the untreated and TiO2+polyacrylonitrile (PAN) modified discarded battery coal (DBC) and pencil graphite electrodes (PGE) were evaluated in fuel cell (FC) applications. TiO2+PAN solution is coated on PGE and DBC electrodes by electrospinning. According to the FESEM and EDS characterizations, TiO2 and PAN nanofibers are found to be approximately 40 and 240 nm in size. TiO2+PAN/PGE showed the best FC performances with 2.00 A cm-2 current density and 5.05 W cm-2 power density values, whereas TiO2+PAN/DBC showed 0.68 A cm-2 current density and 0.62 W cm-2 power density values. Electrochemical characterizations of PGE and TiO2+PAN/PGE electrodes were …

A Review Of Measuring Ecosystem Resilience To Disturbance, Chuixiang Yi, Nathan Jackson

Publications and Research

Resilience is the central concept for understanding how an ecosystem responds to a strong perturbation, and is related to other concepts used to analyze system properties in the face of change such as resistance, recovery, sustainability, vulnerability, stability, adaptive capacity, regime shift, and tipping point. It is extremely challenging to formulate resilience thinking into practice. The current state-of-art approaches of assessing ecosystem resilience may be useful for policy makers and ecosystem resource managers to minimize climatological or natural disaster related impacts. Here, we review the methods of assessing resilience and classify and limit them to three cases: (1) forest resilience …

Effect Of Gradually Water Stress And Recovery On Photosynthesis, Transpiration, And Stomatal Conductance In Two Plantago Species, A. Rahimi, H. R. Rahimian Mashhadi, M. R. Jahansoz

IGC Proceedings (1993-2023)

No abstract provided.

Extracting Information From Subroutines Using Static Analysis Semantics, Luke A. Burnett

Browse all Theses and Dissertations

Understanding how a system component can interact with other services can take an immeasurable amount of time. Reverse engineering embedded and large systems can rely on understanding how components interact with one another. This process is time consuming and can sometimes be generalized through certain behavior.We will be explaining two such complicated systems and highlighting similarities between them. We will show that through static analysis you can capture compiler behavior and apply it to the understanding of a function, reducing the total time required to understand a component of whichever system you are learning.

Quantitative Analysis Of A Stochastic Seitr Epidemic Model With Multiple Stages Of Infection And Treatment, Olusegun M. Otunuga, Mobolaji O. Ogunsolu

Mathematics Faculty Research

We present a mathematical analysis of the transmission of certain diseases using a stochastic susceptible-exposed-infectious-treated-recovered (SEITR) model with multiple stages of infection and treatment and explore the effects of treatments and external fluctuations in the transmission, treatment and recovery rates. We assume external fluctuations are caused by variability in the number of contacts between infected and susceptible individuals. It is shown that the expected number of secondary infections produced (in the absence of noise) reduces as treatment is introduced into the population. By defining R_T,n and ℛ_T,n as the basic deterministic and stochastic reproduction …

The Rockaway Project - Townes, Diara Jepris D. Townes

Capstones

The Rockaway Project is a story-driven website that provides information on the government response to Superstorm Sandy recovery on the Rockaway peninsula in Queens, New York. Dozens of climate resiliency projects have been delayed or remain unfinished, despite millions of dollars in funding and six years of promises. The website hosts audio, visual and digital content, gathered through interviews and data collection.

Link to capstone project: https://www.youtube.com/watch?v=fAq2BeR4bS0&t=1s

Evidence Of Limited Recruitment Of Pallid Sturgeon In The Lower Missouri River, Kirk D. Steffensen, Kimberly Chojnacki, Jeffrey A. Kalie, Meredith L. Bartron, Edward J. Heist, Kyle R. Winders, Nathan C. Loecker, Wyatt J. Doyle, Timothy L. Welker

United States Geological Survey: Staff Publications

Pallid Sturgeon Scaphirhynchus albus are endemic to the Missouri and Mississippi river basins and are rare throughout their range. The species was listed as federally endangered with little to no evidence of natural recruitment. Since population augmentation was initiated as a recovery objective in the early 1990s, thousands of hatchery-origin Pallid Sturgeon have been stocked in the lower Missouri River (Gavins Point Dam [river kilometer 1,305.1] to the confluence of the Mississippi River [river kilometer 0.0]). Efforts to discriminate natural reproduction and recruitment of wild-origin Pallid Sturgeon from hatchery-origin fish has been hampered by tag loss in hatchery-origin sturgeon, inconsistent …

Evaluating Restoration Success By Tracking The Structural And Functional Recovery Of Restored, Drained, And Intact Wetlands, Renee C. Howard

Electronic Thesis and Dissertation Repository

Wetland restoration efforts have increased on the Canadian prairies to compensate for widespread loss of wetland area, form, and function. Restoration activity presumes a direct replacement for natural wetlands, where restored wetlands provide equivalent ecological functions and services. However, restoration projects often show limited recovery success in biological structure and biogeochemical function. Using plant functional traits is an emerging approach to assessing ecological process and may provide a better indicator of wetland functional recovery than vegetation structural indicators alone. Here, I tracked vegetation structural metrics (i.e., species richness, composition, and cover) and plant functional traits over a chronosequence of restored …

Substantial Red Wolf Genetic Ancestry Persists In Wild Canids Of Southwestern Louisiana, Jennifer R. Adams, John J. Cox, Lisette P. Waits

Forestry and Natural Resources Faculty Publications

Concerns over red wolf (Canis rufus) extinction caused by hybridization with coyotes (C. latrans) led to the capture and removal of remnant wild wolves from southwestern Louisiana and southeastern Texas, United States, during the 1970s. Here we show that despite decades of unmitigated hybridization, and declaration of endangered red wolves as functionally extinct in the wild, red wolf mitochondrial or nuclear DNA ancestry persists in ∼55% of contemporary wild canids sampled in southwestern Louisiana. Surprisingly, one individual had 78–100% red wolf ancestry, which is within the range for 75% red wolf, red wolf backcross, or putative …

Does Stream Water Composition At Sleepers River In Vermont Reflect Dynamic Changes In Soils During Recovery From Acidification?, Jesse R. Armfield, Julia N. Perdrial, Alex Gagnon, Jack Ehrenkranz, Nicolas Perdrial, Malayika Cincotta, Donald Ross, James B. Shanley, Kristen L. Underwood, Peter Ryan

College of Arts and Sciences Faculty Publications

Stream water pH and composition are widely used to monitor ongoing recovery from the deposition of strong anthropogenic acids in many forested headwater catchments in the northeastern United States. However, stream water composition is a function of highly complex and coupled processes, flowpaths, and variations in soil and bedrock composition. Spatial heterogeneity is especially pronounced in headwater catchments with steep topography, potentially limiting stream water composition as an indicator of changes in critical zone (CZ) dynamics during system recovery. To investigate the link between catchment characteristics, landscape position, and stream water composition we used long-term data (1991–2015) from the Sleepers …