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Articles 61 - 90 of 222
Full-Text Articles in Environmental Engineering
Re-Aerosolization Of Dense Metal Oxide Simulating Radiological Contamination From Military Clothing, Joseph M. Chapman
Re-Aerosolization Of Dense Metal Oxide Simulating Radiological Contamination From Military Clothing, Joseph M. Chapman
Theses and Dissertations
Radiological contamination from nuclear accidents or the terrorist use of a Radiological Dispersal Device (RDD) are events that first responders must be prepared for. It is currently assumed that removal of the victims clothing will remove 80-90 of contamination. Many RDD radioisotopes produce dense aerosols that would then contaminate victim clothing and re-aerosolize during clothing removal. A series of experiments were conducted during which clothing was contaminated with a dense aerosol simulating the radioisotope of Strontium 90. Compared to background, there was statistically significant re-aerosolization from the clothing. This demonstrates inhalation hazards from re-aerosolization of RDD contamination.
An Analysis Of Various Hydrogen Production Methods For Fleet Vehicle Fuel, Eugene J. Denezza Ii
An Analysis Of Various Hydrogen Production Methods For Fleet Vehicle Fuel, Eugene J. Denezza Ii
Theses and Dissertations
As conflict, the environment, and politics cause changes around the world, the United States Air Force is pursuing a diversification of drop-in and alternative fuel sources. Hydrogen fuel cells for vehicles are gaining popularity worldwide. Yet, how to best produce hydrogen gas still remains a question. This thesis will provide an overview of various hydrogen production methods and their respective environmental impacts, costs, efficiencies, and viability; and will perform sensitivity analysis to determine an optimal solution. The optimal production method is Thermolysis followed by Steam Reformation of Landfill or Natural Gas, Coal Gasification, and PEM Electrolysis. Based on varying requirements …
The Effect Of Molar Peroxide Ratio On The Oxidation Of 2,4-Dinitroanisole In An Ultraviolet Light Emitting Diode Advanced Oxidation Process, Troy M. Searcy
The Effect Of Molar Peroxide Ratio On The Oxidation Of 2,4-Dinitroanisole In An Ultraviolet Light Emitting Diode Advanced Oxidation Process, Troy M. Searcy
Theses and Dissertations
Insensitive munitions (IMs) are increasingly employed by the U.S. military to prevent unintended detonations associated with conventional munitions. One IM used extensively is 2,4 dinitroanisole (DNAN). This research employed an ultraviolet light emitting diode (LED) and hydrogen peroxide advanced oxidation process (AOP) to treat DNAN-contaminated water at the laboratory scale. Five molar peroxide ratios (50:1, 100:1, 250:1, 500:1, 1000:1) were evaluated using the observed pseudo first-order rate constant as the performance metric. Both peroxide-limiting reactions and radical scavenging were observed over the range of ratios tested, with overall removal of DNAN decreasing above a ratio of 500:1.
The Effect Of Molar Peroxide Ratio On The Oxidation Of Bisphenol A In An Ultraviolet Light Emitting Diode/Hydrogen Peroxide Advanced Oxidation Process, Megan C. Shade
Theses and Dissertations
Bisphenol A is a compound widely used in industry that is detrimental to human health and ecological systems. Ultraviolet light emitting diodes and hydrogen peroxide can be combined t produces hydroxyl radicals. These highly reactive radicals have the potential to degrade contaminants in water. This research utilized 50, 100, 250, 500, and 1000:1 H2O2:BPA molar ratios for analysis. These results illustrated that the reactions at the 50, 100, and 250:1 ratios were hydrogenperoxide limited. The 1000:1 results exhibited evidence of radical scavenging that limited the degradation of BPA.
Evaluation Of Efficient Water Reuse Technologies For Sustainable Forward Operating Bases, Kelsie L. Crouch
Evaluation Of Efficient Water Reuse Technologies For Sustainable Forward Operating Bases, Kelsie L. Crouch
Theses and Dissertations
A secure water source is essential to the resiliency and readiness of military installations and contingency operation locations, especially those located in the dry climates the US military operates in today. There are multiple issues of concern when identifying water sources, such as security, cleanliness, accessibility, and sustainability. Water resources pose a potential vulnerability to mission readiness in a remote, agile environment, such as a forward operating base (FOB). Having a secure water resource helps facilitate mission readiness in the contingency environment, offering the opportunity to be more resilient and cost-effective. Current water treatment technologies present the possibility to perform …
Fluid Dynamics Modeling For Per- And Polyfluoroalkyl Substances Removal In Legacy Fire Suppression Systems, Jacob G. Spaulding
Fluid Dynamics Modeling For Per- And Polyfluoroalkyl Substances Removal In Legacy Fire Suppression Systems, Jacob G. Spaulding
Theses and Dissertations
Legacy per- and polyfluoroalkyl substances (PFASs) exist in the form of aqueous film-forming foams within hangar fire suppression systems throughout the country, posing a threat to both surrounding environments as well as local populations. The United States (US) Department of Defense (DoD), in conjunction with the US Environmental Protection Agency (EPA), is investigating best practices to flush out existing contaminants prior to disposal and replacement with a less environmentally harmful replacement. While current procedures dictate a triple rinse of the entire system to yield contaminant levels acceptable to the DoD, the practice has never truly been tested. Designed as a …
An Analysis Of Tinker Air Force Base Thermal Spray Hazardous Waste Stream From 2003-2019 And Its Potential Reclamation, Amy E. Silverbush
An Analysis Of Tinker Air Force Base Thermal Spray Hazardous Waste Stream From 2003-2019 And Its Potential Reclamation, Amy E. Silverbush
Theses and Dissertations
The disposal of hazardous waste threatens the environment and human health. However, certain hazardous wastes can be recycled or reclaimed to alleviate environmental and financial impacts associated with its disposal and resource demand reduction. A hazardous powder produced by the United States Air Force stems from aircraft maintenance and is composed of metals and ceramics, called thermal spray. This waste can be purchased by an industrial recycler if the waste is composed of valuable metals. Historic data from the depot-level maintenance base Tinker Air Force Base initiated an analysis of annual thermal spray hazardous waste disposal fees, which combined with …
Comparison Of The Pfas Adsorption Capabilities Of A Coconut Shell Based Granular Activated Carbon And A Bituminous Coal Based Granular Activated Carbon, Matthew D. Holliday
Comparison Of The Pfas Adsorption Capabilities Of A Coconut Shell Based Granular Activated Carbon And A Bituminous Coal Based Granular Activated Carbon, Matthew D. Holliday
Theses and Dissertations
This research compares the ability of two granular activated carbons (GAC) from different material sources to adsorb perfluoroalkyl substances (PFAS) in deionized water. A bottle study design was used to conduct the research, which measured the reduction in perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). The carbons used were the bituminous coal based Calgon Filtrasorb 600 (F600) and the coconut shell based Evoqua AquaCarb 1230CX (AC1230CX). Additionally, the research focused on the rates at which the two contaminants were removed and compared them to previous research conducted with different forms of GAC. Results showed that both GACs were capable …
The Effect Of Aeration Rate And Free-Floating Carrier Media On The Emission Of Bacillus Globigii In Bioaerosols, Andrew J. Owens
The Effect Of Aeration Rate And Free-Floating Carrier Media On The Emission Of Bacillus Globigii In Bioaerosols, Andrew J. Owens
Theses and Dissertations
Aerosols produced by turbulent mechanical mixing and bubble aeration at Waste Water Treatment Plants (WWTPs) become bioaerosols with the entrainment of biological materials. Bioaerosols become a public health risk when human pathogens are present. This study evaluated bioaerosols containing Bacillus globigii (BG) spores, and the effects that aeration rate and the addition of Free-Floating Carrier Media (FFCM) had on the amount of BG spores collected following aerosolization. A series of laboratory-scale experiments investigated two different sizes of floating polystyrene spheres as FFCM and four different aeration rates. When the differences in compared aeration rates were sufficiently large, a positive correlation …
Using Nano- And Micro- Structural Materials For Concrete Environmental Applications, Hala Nabeel Elia
Using Nano- And Micro- Structural Materials For Concrete Environmental Applications, Hala Nabeel Elia
Theses and Dissertations
Utilized globally in the construction industry, concrete is an integral component of homes, roads, airports, skyscrapers, and tunnels. Traditional concrete components are cement, fine aggregate (sand), coarse aggregate (gravel or crushed stone), and water. When cement and water compound together they will make a paste which binds all the aggregates together to make the concrete. Unfortunately, every one ton of cement manufactured emits 0.9 ton of CO2into the air. The goal of this two-part work was to obtain an environmentally friendly concrete. The first part used supplementary cementitious materials (SCM), fly ash and silica fume, to create concrete with high …
Development Of A Subsurface Landfill Fire Risk-Index, Samain Sabrin
Development Of A Subsurface Landfill Fire Risk-Index, Samain Sabrin
Theses and Dissertations
Landfill subsurface fires create environmental hazards by emitting potentially dangerous particulates into the atmosphere and damaging liners, potentially contaminating surrounding soil and groundwater aquifers with leachate. Currently, the only means of detecting underground fires are physical tests. This paper is used to describe an index that can be employed to track fire risk across a landfill. The landfill parameters analyzed for fire risk susceptibility in Chapter 1 include residual nitrogen concentration, oxygen exceedance, methane concentration, carbon monoxide level, methane and carbon dioxide ratio and monitoring well temperature. Incorporating these factors, a landfill fire index ranging from 1 to 10 was …
A Surprising Symbiosis: Examining The Mutualism In Department Of Defense Conservation Partnerships, Andrew J. Lankow
A Surprising Symbiosis: Examining The Mutualism In Department Of Defense Conservation Partnerships, Andrew J. Lankow
Theses and Dissertations
Because of the DoD’s unique and significant role in the conservation of natural resources, military leaders and natural resource managers need a trail guide to frame interagency collaboration in a way that shapes productive partnerships. The purpose of this research was to examine successful DoD conservation partnerships in order to identify key success factors (KSFs) and the most prominent challenges faced, and how those characteristics enable the accomplishment of each partner’s objectives. The research questions were answered through a comprehensive literature review and the use of the multiple-case study method. 19 key informants from three installations participated in semi-structured interviews, …
Cost And Performance Difference Of High Performance Sustainable Buildings, Philip A. Ramsey
Cost And Performance Difference Of High Performance Sustainable Buildings, Philip A. Ramsey
Theses and Dissertations
Varying legislation and executive orders coupled with needs for energy resiliency have led the United States Air Force to pursue sustainable construction. The limited understandings of initial costs to implement these changes have contributed to poor project cost estimating and changed implementation of legal requirements. A student t-test for populations with unequal variance was accomplished on the final normalized contract cost of 1628 Air Force Military Construction (MILCON) projects executed between 2002 and 2017. Future design considerations for net zero energy buildings were compiled from a net zero energy residential community in Fontana, California. There was no statistically significant difference …
The Effect Of Ms2 Bacteriophage On The Activity And Performance Of Activated Sludge, Sean M. Stuntz
The Effect Of Ms2 Bacteriophage On The Activity And Performance Of Activated Sludge, Sean M. Stuntz
Theses and Dissertations
As a medical waste product, the MS2 bacteriophage has been discharged into wastewater distribution and treatment networks. To categorize its impact to suspended growth treatment methods, this research investigated the effect of the MS2 bacteriophage on activated sludge through a series of respirometry tests. The effects of MS2 bacteriophage at a concentration of 3.2x108 PFU/mL were assessed by determining peak O2 consumption, cumulative O2 consumption, molar CO2/O2 ratios, and shape factors. None of the MS2 samples caused statistically significant effects on the peak or cumulative O2 consumption. The molar CO2/O2 …
Dynamics Of Chemical Degradation In Water Using Photocatalytic Reactions In An Ultraviolet Light Emitting Diode Reactor, John E. Stubbs
Dynamics Of Chemical Degradation In Water Using Photocatalytic Reactions In An Ultraviolet Light Emitting Diode Reactor, John E. Stubbs
Theses and Dissertations
This work examined ultraviolet (UV) light emitting diodes (LED) and hydrogen peroxide in an advanced oxidation process in support of a USAF installation net zero water initiative. A UV LED reactor was used for degradation of soluble organic chemicals. There were linear relationships between input drive current, optical output power, and first order degradation rate constants. When drive current was varied, first order degradation rates depended on chemical identities and the drive current. When molar peroxide ratios were varied, kinetic profiles revealed peroxide-limited or radical-scavenged phenomena. Molar absorptivity helped explain the complexity of chemical removal profiles. Degradation kinetics were used …
Characterization Of Jet Fuel Combustion Emissions During A C-130 Aeromedical Evacuation Engines Running Onload, Michelle L. Page
Characterization Of Jet Fuel Combustion Emissions During A C-130 Aeromedical Evacuation Engines Running Onload, Michelle L. Page
Theses and Dissertations
The purpose of this research was to characterize jet fuel combustion emissions (JFCE) in an occupational setting. Prior research demonstrated that aircraft emit hazardous species, especially at engine start-up and ground idle. Complaints of eye, nose, and throat irritation from occupational exposures near aircraft exist. In this study JFCE were tested during an aeromedical evacuation engines running patient onload (ERO) on a C-130 Hercules at the 179th Airlift Wing, Mansfield-Lahm Air National Guard. Ultrafine particles, VOC, formaldehyde, carbon monoxide (CO), sulfuric acid, and metals were sampled simultaneously in approximate crew and patient breathing zones. Testing methods were portable condensation …
Adsorption Of Perfluorinated Compounds From Post-Emergency Response Wastewater, Christopher T. Schmidt
Adsorption Of Perfluorinated Compounds From Post-Emergency Response Wastewater, Christopher T. Schmidt
Theses and Dissertations
This research investigated the efficacy of granular activated carbon (GAC) as a method to treat water impacted with aqueous film forming foam (AFFF) after a firefighting response. Bench-top experiments were conducted and compared to field scale adsorber performance removing mg/L concentrations of PFAS in water contaminated with Military Specification AFFF. Batch tests compared four adsorbents, and determined Calgon F600 GAC and Rembind Plus mixed carbon media had the greatest perfluorooctane sulfonate (PFOS) capacities. Additional batch isotherm experiments using AFFF and higher PFOS concentrations (mg/L) indicated larger amounts of GAC are required (>30mg/L) for effective removal. Full-scale testing simulated an …
Toxicological Differences Between Perfluoroalkyl Substances (Pfas) Isomers Using Developmental Biomarkers, Gabriel A. Cantu
Toxicological Differences Between Perfluoroalkyl Substances (Pfas) Isomers Using Developmental Biomarkers, Gabriel A. Cantu
Theses and Dissertations
Perfluoroalkyl substances (PFAS) are metabolically stable synthetic chemicals that have been manufactured for commercial and industrial purposes since the 1950s. PFAS possess surfactant properties that make them ideal to fight hydrocarbon fires and are therefore present in aqueous film forming foams (AFFF). Furthermore, AFFF may contain blends of both linear and branched PFAS isomers. Research suggests that branched PFAS isomers have greater relative placental transfer efficiencies than their linear counterpart, but few studies have evaluated their toxicity. Therefore, the sustained use of AFFF in the U.S. Air Force presents a risk of branched PFAS exposures in pregnant females. This study …
A Simulation-Based Analysis Of Chemical And Radiological Hazard Zones Adapted To Physical Boundaries, Mickie J. Sundheim
A Simulation-Based Analysis Of Chemical And Radiological Hazard Zones Adapted To Physical Boundaries, Mickie J. Sundheim
Theses and Dissertations
In the United States, industrial and terrorist use of chemical, biological, radiological, and nuclear (CBRN) materials pose a risk to public safety. During the initial phase of typical CBRN incidents, emergency responders establish hazard zones based on standard distances from published guidelines and recommendations. This research investigates how standard hazard zones change in a real world environment that accounts for physical boundaries. Using a python simulation in ArcGIS®, new hazard zones were created by expanding standard hazard zones to follow nearby roads, railroads, and rivers. The new and standard zones were compared by calculating the population and area affected by …
The Effect Of Ph And Pulsed Ultraviolet Light Emitting Diode Duty Cycles On The First Order Rate Constant And Byproduct Profile Of The Advanced Oxidation Of Tartrazine, Brandon M. Stewart
The Effect Of Ph And Pulsed Ultraviolet Light Emitting Diode Duty Cycles On The First Order Rate Constant And Byproduct Profile Of The Advanced Oxidation Of Tartrazine, Brandon M. Stewart
Theses and Dissertations
Water treatment capability is required for military operations, production of drinking water, and industrial wastewater treatment. The Advanced Oxidation Process (AOP) is one of many viable steps for treating water; however, it is important to understand the byproducts of the treatment process to avoid creating other constituents more severe than the first. Tartrazine (TAR) was oxidized with pulsed Ultra- Violet (UV) Light Emitting Diodes (LEDs) in combination with hydrogen peroxide (H2O2) in an AOP at the laboratory scale. The relative concentration of TAR was reduced from 1 to between 1 – 0.75 over pH values between 6 and 9, and …
Removal Of Perfluorooctanoic Acid From Water Using Primitive, Conventional And Novel Carbonaceous Sorbent Materials, Christopher K. Brown
Removal Of Perfluorooctanoic Acid From Water Using Primitive, Conventional And Novel Carbonaceous Sorbent Materials, Christopher K. Brown
Theses and Dissertations
Polyfluoroalkyl Substances (PFAS), like perfluorooctanoic acid, have been used for the last 50 years in a wide variety of industrial processes and consumer-based products, including polymer additives, lubricants, fire retardants and suppressants, pesticides, and surfactants (Buck et al. 2015). The Department of Defense (DoD) has used PFAS-based Aqueous Film Forming Foam (AFFF) at fire training facilities and aircraft hangars. AFFF has contaminated approximately 600 sites classified as fire training facilities with PFAS (Huang, 2013).
This study focused on testing the most likely carbonaceous adsorbent compounds to remediate PFAS-contaminated sites on Air Force installations. Batch tests were performed to determine the …
Material And Design Considerations For A Portable Ultra-Violet (Uv) Light Emitting Diode (Led) Water Purification Device, Drew D. Gallucci
Material And Design Considerations For A Portable Ultra-Violet (Uv) Light Emitting Diode (Led) Water Purification Device, Drew D. Gallucci
Theses and Dissertations
Department of Defense personnel often deploy to austere environments where clean water is not readily available. Ultraviolet (UV) radiation through the use of light emitting diodes (LEDs) in a portable device offers a potential method for expedient water treatment. This research studied the application of one diode, low power, UV LEDs and nine diode, high power, UV LEDs within a portable steel reactor and Teflon reactors of three different wall thicknesses. Reactor efficiency was determined through measuring and comparing the rate constants for Advanced Oxidation of hydrogen peroxide with yellow tartrazine as a witness dye. Experiments conducted with low power …
Characterizing Emissions From Open Burning Of Military Food Waste And Packaging From Forward Operating Bases, Thomas Dominguez
Characterizing Emissions From Open Burning Of Military Food Waste And Packaging From Forward Operating Bases, Thomas Dominguez
Theses and Dissertations
Emissions were characterized and compared from the open burning of four compositions of Meals, Ready-To-Eat (MRE) and four types of MRE fiberboard packaging in response to inhalation concerns at military forward operating bases. Measurements of particulate matter (PM2.5, PM10) showed that MREs account for 70-90 percent of PM emissions when burned in unison with the current fiberboard container and liner and that PM2.5 constitutes a vast majority of the particulates emitted. Targeted replacement of MRE constituents may be more effective in reducing volatile organic compound (VOC) and polycyclic aromatic hydrocarbon (PAH) emissions than the variation of fiberboard packaging designs, while …
A System Dynamics Approach To The Efficacy Of Oxime Therapy In Sub Lethal Exposure To Sarin Gas, Daniel J. Droste
A System Dynamics Approach To The Efficacy Of Oxime Therapy In Sub Lethal Exposure To Sarin Gas, Daniel J. Droste
Theses and Dissertations
The 2010 National Security Strategy states, The effective dissemination of a lethal agent would endanger the lives of thousands of people and have unprecedented economic, societal, and political consequences. We must continue to work at home with first responders and health officials to reduce the risk associated with high-consequence threats . Nerve agents, such as Sarin gas, are considered high consequence threats. The threat of use of agents such as Sarin is as much a threat today as any other time in our history. However, the suggested treatment protocol is not as precise as it could be. Debate exists over …
Pulsed Ultraviolet Light Emitting Diodes For Advanced Oxidation Of Tartrazine, Patrick M. Mudimbi
Pulsed Ultraviolet Light Emitting Diodes For Advanced Oxidation Of Tartrazine, Patrick M. Mudimbi
Theses and Dissertations
A study was conducted to evaluate the advanced oxidation of organic contaminants using pulsed ultraviolet light emitted diode (UV LED). Tartrazine was used as a surrogate organic compound. Low pressure Mercury-based lamps currently used in the treatment of water pose potential health risks if broken and create final disposal issues at the end of their service life. UV LED offers an alternative solution due to its non-toxicity, flexible design, and longer operating life compared to the mercury-based lamps. The apparent first order reaction rate constant for tartrazine degradation increased linearly with increasing duty cycle. At a continuous 100% duty cycle, …
The Effect Of Malathion On The Activity And Performance Of Activated Sludge, Erik G. Rauglas
The Effect Of Malathion On The Activity And Performance Of Activated Sludge, Erik G. Rauglas
Theses and Dissertations
Decontamination activities following a chemical weapons incident may generate significant quantities of contaminated wash water that may enter the wastewater collection system either intentionally or accidentally. This raises concerns about the effect of chemical warfare agents (CWAs) on the operation of a biological wastewater treatment plant. The goal of the study was to evaluate the effect of malathion on the activity and performance of activated sludge. Malathion is an organophosphate (OP) and is considered an environmental surrogate for VX. This study employed respirometry, short term batch tests, and long term exposure experiments to investigate the effects of different concentrations of …
Micro- And Macro-Scale Modeling Of Filter Aging: Effects Of Particle Poly-Dispersity And Fiber Cross-Sectional Shape, Ahmed M. Saleh
Micro- And Macro-Scale Modeling Of Filter Aging: Effects Of Particle Poly-Dispersity And Fiber Cross-Sectional Shape, Ahmed M. Saleh
Theses and Dissertations
The goal of this study is to further advance the state of the art in developing self-sufficient methods to predict the performance of an aerosol filter. The simulation methods developed in this study are based on first principles and consequently, they do not rely on empirical correction factors. These simulation methods can be used to predict the instantaneous collection efficiency and pressure drop of a filter under dust-loading conditions. In the current study, 3-D micro- and macroscale CFD models are developed to simulate the service life of flat-sheet and pleated filters. These CFD micro- and macroscale models are also used …
Ultraviolet Light Emitting Diode Use In Advanced Oxidation Processes, Kelsey L. Duckworth
Ultraviolet Light Emitting Diode Use In Advanced Oxidation Processes, Kelsey L. Duckworth
Theses and Dissertations
Cleanup from a hazardous chemical release can result in large volumes of water containing hazardous materials, such as organophosphates. Unfortunately, this water cannot be treated in a municipal wastewater treatment plant without adversely affecting the performance of the plant. A known method for pretreating this water to prepare it for processing in a traditional treatment plant includes the addition of hydrogen peroxide, followed by ultraviolet (UV) light exposure to form reactive hydroxyl radicals which oxidize the chemical. Light emitting diodes (LEDs) are explored as a UV source as they are durable; compact; can be powered by low voltage, direct current …
Design Considerations For A Water Treatment System Utilizing Ultra-Violet Light Emitting Diodes, Michael J. Spencer
Design Considerations For A Water Treatment System Utilizing Ultra-Violet Light Emitting Diodes, Michael J. Spencer
Theses and Dissertations
UV LED technology is in its infancy and research as it applies to UV water treatment is required to advance knowledge for practical application. This thesis focused on two subjects. First, the design, fabrication, and operation of a water treatment reaction system utilizing Ultra-Violet (UV) Light Emitting Diodes (LEDs). Second, the measurement of UV LED output angle in water which is necessary to support future reactor designs. Several characteristics of the LED-water interface were revealed which impacted the effectiveness of the vessel including; UV dose requirements, LED wavelength, photon dispersion geometry, LED placement, optical efficiency, vessel material, and electronic control …
Development Of Peptide Nanotube-Modified Biosensors For Gas-Phase Organophosphate Detection, Peter A . Baker
Development Of Peptide Nanotube-Modified Biosensors For Gas-Phase Organophosphate Detection, Peter A . Baker
Theses and Dissertations
Vapor-phase detection of the model organophosphate malathion was achieved using enzymes encapsulated in peptide nanotubes and attached to gold screen-printed electrodes. Malathion was chosen as the model for this experiment because its binding mechanism with acetylcholinesterase (AChE) is identical to its more potent counterparts (such as sarin or VX), but it has an extremely low human toxicity, which makes it both practical and easy to use. The peptide nanotubes had horseradish peroxidase encapsulated inside and were coated with both acetylthiocholine (ASCh) and AChE on the outside. ASCh hydrolysis, which produces thiocholine, was catalyzed by the AChE. The thiocholine was then …