11 Jan 2024

Classifying and Benchmarking High-Entropy Alloys and Associated Materials for Electrocatalysis: A Brief Review of Best Practices

Abstract: In light of the immense compositional diversity of high-entropy materials (HEMs) recently reported (e.g., high-entropy chalcogenides, perovskites, ceramics, etc.) and the relatively amorphous definition of High-Entropy, it is imperative that consistent material classification and benchmarking practices be employed to facilitate comparison between reported figures of merit. In this opinion, an updated form of the numerical high entropy definition is reviewed, which renders a universal entropy metric applicable to high-entropy alloys and emerging HEMs alike. Analytical methods to verify the existence of a solid-solution microstructure, elucidate atomic valence states, and probe atomic disorder are discussed with literature examples to facilitate the physical classification of HEMs. Electrocatalytic benchmarking is discussed in the context of water splitting reactions and best practices are reviewed for determining the electrocatalytically active surface area, reaction overpotential, and electrocatalyst stability.

8 Jan 2024

Scaled-Up Synthesis of Water-Retaining Alginate-Based Hydrogel

Purpose: Synthesis of a scaled-up version of a lithium-ion-based alginate/poly(acrylamide-co-stearyl methacrylate) [Li-alginate/P(AAm-co-SMA)] hydrogel with several optimizations for thermal signature investigations on various environmental substrates.

8 Jan 2024

Assessing Differences in the Wetland Functional Capacity of Wet Pine Flatwood Compensatory Mitigation Sites Managed with Prescribed Fire and Mechanical Mowing

Abstract: This report assesses the functional capacity of wet pine flatwood wetland habitats in the Gulf Coastal region of the United States, with a specific focus on compensatory mitigation sites maintained using mowing or prescribed fire, or both, as understory management strategies. The use of mowing in lieu of prescribed fire treatments has been proposed for a variety of reasons, including when mitigation sites are located near residential areas or where fires pose a risk to private property and public safety. This study evaluates the effects of mechanized mowing on ecosystem functions by using the hydrogeomorphic (HGM) wetland functional-assessment method to compare mitigation sites managed by mowing to sites managed by prescribed-fire regimes. Assessing mowing as a vegetation-control strategy in lieu of prescribed-fire regimes provides valuable information that can improve the design and management of wet pine flatwoods mitigation sites throughout portions of the southeastern United States, where this wetland class occurs.

4 Jan 2024

Radio Frequency Heating of Washable Conductive Textiles for Bacteria and Virus Inactivation

Abstract: The ongoing COVID-19 pandemic has increased the use of single-use medical fabrics such as surgical masks, respirators, and other personal protective equipment (PPE), which have faced worldwide supply chain shortages. Reusable PPE is desirable in light of such shortages; however, the use of reusable PPE is largely restricted by the difficulty of rapid sterilization. In this work, we demonstrate successful bacterial and viral inactivation through remote and rapid radio frequency (RF) heating of conductive textiles. The RF heating behavior of conductive polymer-coated fabrics was measured for several different fabrics and coating compositions. Next, to determine the robustness and repeatability of this heating response, we investigated the textile’s RF heating response after multiple detergent washes. Finally, we show a rapid reduction of bacteria and virus by RF heating our conductive fabric. 99.9% of methicillin¬resistant Staphylococcus aureus (MRSA) was removed from our conductive fabrics after only 10 min of RF heating; human cytomegalovirus (HCMV) was completely sterilized after 5 min of RF heating. These results demonstrate that RF heating conductive polymer-coated fabrics offer new opportunities for applications of conductive textiles in the medical and/or electronic fields.

4 Jan 2024

Influence of Chemical Coatings on Solar Panel Performance Snow Accumulation

Abstract: Solar panel performance can be impacted when panel surfaces are coated with substances like dust, dirt, snow, or ice that scatter and/or absorb light and may reduce efficiency. As a consequence, time and resources are required to clean solar panels during and after extreme weather events or whenever surface coating occurs. Treating solar panels with chemical coatings that shed materials may decrease the operating costs associated with solar panel maintenance and cleaning. This study investigates three commercial coatings for use as self-cleaning glass technologies. Optical and thermal properties (reflectivity, absorption, and transmission) are investigated for each coating as well as their surface wettability and particle size. Incoming solar radiation was continuously monitored and snow events were logged to estimate power production capabilities and surface accumulation for each panel. In terms of power output, the commercial coatings made little impact on overall power production compared to the control (uncoated) panels. This was attributable to the overall high transmission, low absorption, and low reflection of each of the commercial coatings, making their presence on the surface of solar panels have minimal impact besides to potentially shed snow While the coatings made no observable difference to increase power production compared to the control panels, the shedding results from video monitoring suggest both the hydrophilic or hydrophobic test coatings decreased snow accumulation to a greater extent than the control panels (uncoated). Controlling the wettability properties of the solar panel surfaces has the potential to limit snow accumulation when compared to uncoated panel surfaces.

28 Nov 2023

Investigation of Steam Adsorption Chillers to Modernize Existing Central Steam Plant Systems

Abstract: This report investigates the integration of steam adsorption chillers as a modernization strategy for conventional central steam plant systems. Our objective is to assess the feasibility, advantages, and challenges of incorporating steam adsorption chillers into existing steam plant setups to enhance energy efficiency and cooling capabilities. Central steam plant systems have historically been used for steam-based heating but often lack cooling capabilities, necessitating additional cooling infrastructure. Steam adsorption chillers offer a potential solution by using waste steam for cooling, optimizing energy utilization and reducing reliance on traditional cooling methods. Through a comprehensive analysis, this report evaluates the technical compatibility and potential cost implications of implementing steam adsorption chillers. It explores factors such as system integration, operational dynamics, and maintenance requirements to provide a holistic view of the feasibility and benefits of this modernization approach. The findings aim to offer valuable insights to decision-makers and Army facility managers seeking innovative ways to upgrade central steam plant systems. By considering the technical and economic aspects of adopting steam adsorption chillers, this report contributes to the knowledge base for sustainable and efficient energy utilization in central plant operations.

20 Nov 2023

Internal Standard and Deuterated Solvent Selection: A Crucial Step in PFAS-based Fluorine-19 (¹⁹F) NMR Research

Purpose: This work is vital because it provides researchers with a framework and rationale for selecting the best internal standard and deuterated solvent for their nuclear magnetic resonance (NMR) analysis of per- and polyfluoroalkyl substances (PFAS)-based compounds. Selecting the best internal standard and deuterated solvent will help to ensure that their results are accurate, precise, and sensitive. The internal standard that is chosen can significantly affect the accuracy, precision, sensitivity, and quantification of NMR measurements. Therefore, it is essential to carefully select an internal standard and a matching deuterated solvent that are well-suited for analyzing PFAS compounds.

17 Nov 2023

Advancing Engineering With Nature Initiatives in Point Hope, Alaska

Purpose: Growing environmental risk threatens communities in cold regions, particularly as climate change contributes to permafrost thaw, a reduction in sea-ice extent, and some of the largest rates of coastal erosion on earth. In the context of these significant and growing risks, the Engineering With Nature® (EWN®) program formed its cold regions work unit in 2021 to explore the potential to apply EWN approaches in these areas to mitigate environmental risk while supporting resilient outcomes. The work unit’s objectives include working with communities to preserve the natural environment and traditions, advancing the work unit’s understanding of cold-region environments, and providing guidance on the implementation of natural and nature-based features (NNBF) and EWN in cold regions to increase resilience. This technical note (TN) provides an overview of the EWN in cold regions technical approach as applied to Point Hope, Alaska, which includes community engagement, the integration of traditional ecological knowledge (TEK) throughout the project, and the development of cold-regions-specific knowledge and tools.

8 Nov 2023

Environmental Monitoring of Munitions Constituents During a Demonstration of the Underwater Cut-and-Capture System Demilitarization Technology

PURPOSE: The presence of underwater military munitions (UWMM) in aquatic environments may present explosive blast risks and potentially affect the environment because of the release of munitions constituents (MC). Therefore, in situ demilitarization of UWMM is highly desirable. This technical note presents the results of environmental monitoring measuring water and sediment contamination resulting from the demonstration of an in situ technology that uses high-pressure water jets to render UWMM safe.

31 Oct 2023

Marine Bioinvasion Risk: Review of Current Ecological Models

Abstract: This special report describes the first phase of developing an ecological model to inform marine bioinvasion risks in the United States. The project responds to the needs of the US Army Corps of Engineers (USACE) Aquatic Nuisance Species Research Program, or ANSRP, which addresses all problematic invasive aquatic species affecting the nation’s waterways, infrastructure, and associated resources, and the needs of the USACE navigation and dredging programs. Multiple port-deepening studies are either in progress or under consideration, and all must address ecological risk. Understanding whether and how increased dredging contributes to in-creased marine bioinvasion risk allows risk mitigation during early planning phases. Considering the potential impacts of future environmental change, such as changing sea level, ocean temperature, and ocean chemistry, will further strengthen planning for marine bioinvasion risk. There-fore, this special report documents current ecological modeling approaches to marine bioinvasion risk models and identifies models that in-corporate shipping as a vector. The special report then presents a conceptual model and identifies historic vessel position data from the Automatic Identification System, or AIS, now available for most commercial and some recreational vessels around the United States, as a key source for future model development and testing.