Download or read book Sterilization and Decontamination of Surfaces Contaminated With Biological and Chemical Warfare Agents Using Atmospheric Pressure Plasma Discharges written by and published by . This book was released on 1999 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our Phase I effort was meant to demonstrate that an effective technology for rapid surface sterilization of biological contaminants and neutralization of chemical warfare agents could be developed based on the application of an atmospheric pressure plasma. We used both a DC corona and dielectric barrier discharge for the sterilization tests which were conducted on a variety of substrates including metals and chemically resistant fabrics. Medically accepted biological indicator spores (Bacillus subtilis var niger and Bacillus stearothermophilus) were used to determine the effectiveness of the plasma discharge. The chemical neutralization tests were conducted using a DC corona discharge on a metal substrate contaminated with either diisopropylmethyl phosphonate or dimethylmethyl phosphonate. These simulants are of similar chemical structure to classes of chemical warfare agents like GB and Sarin. Results include decomposition of the chemical agent simulants with decomposition by-products including water, acetic acid and gases like CO2; complete sterilization in 15 minutes of some substrates contaminated with up to 105 spores over about a 1 cm2 and the concentration of the model pathogens and the surface characteristics of the contaminated substrate affects the sterilization results. A rough surface with defects is difficult to completely sterilize on short time scales
Download or read book Atmospheric pressure Plasma Decontamination sterilization Chamber written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An atmospheric-pressure plasma decontamination/sterilization chamber is described. The apparatus is useful for decontaminating sensitive equipment and materials, such as electronics, optics and national treasures, which have been contaminated with chemical and/or biological warfare agents, such as anthrax, mustard blistering agent, VX nerve gas, and the like. There is currently no acceptable procedure for decontaminating such equipment. The apparatus may also be used for sterilization in the medical and food industries. Items to be decontaminated or sterilized are supported inside the chamber. Reactive gases containing atomic and metastable oxygen species are generated by an atmospheric-pressure plasma discharge in a He/O.sub. 2 mixture and directed into the region of these items resulting in chemical reaction between the reactive species and organic substances. This reaction typically kills and/or neutralizes the contamination without damaging most equipment and materials. The plasma gases are recirculated through a closed-loop system to minimize the loss of helium and the possibility of escape of aerosolized harmful substances.
Download or read book Plasma Assisted Decontamination of Biological and Chemical Agents written by Selçuk Güçeri and published by Springer Science & Business Media. This book was released on 2011-10-12 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma decontamination is a rapidly expanding area of modern science and engineering. An increasing number of engineers are using plasma methods for decontamination of chemical and biological agents. Plasma decontamination is effectively applied today to clean and sterilize different surfaces, high volume air and water streams, industrial exhausts, and even living tissue of animals and humans. This book provides a fundamental introduction to virtually all aspects of modern plasma decontamination, as well as the most recent technological achievements in the area. The book is segmented into four specific sections of modern plasma decontamination: (1) plasma bio-decontamination, including disinfection and sterilization of surfaces, water and air streams; (2) plasma decontamination of chemical agents, including cleaning of air, water, and industrial exhaust gases from different pollutants and especially volatile organic compounds VOC; (3) plasma treatment of living tissue, including different subjects of plasma medicine from skin sterilization to tissue engineering; (4) major electric discharges applied for the plasma-assisted decontamination of chemical and biological agents.
Download or read book A DC Atmospheric Corona Discharge System for Sterilization and Chemical Neutralization written by Eusebio Garate and published by . This book was released on 1998 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our phase I research effort was meant to demonstrate that an effective technology for rapid sterilization of biological contaminants and neutralization of chemical warfare agents could be developed based on the application of an atmospheric pressure nonthermal plasma generated from a corona discharge. The effort was divided into two main technical objectives and a third task. The first technical objective was the construction and testing of the atmospheric pressure plasma discharge system. The corona discharge was generated by a pin array electrode that could be biased either DC, AC or pulsed. The second technical objective was the application of the system to rapid sterilization of simple biological contaminants and decomposition of chemical warfare agent simulants. Escherichia coli and bacillus subtilus cells were used as the biological contaminants. Diisopropylmethyl phosphonate and dimethylmethyl phosphonate were used to model chemical warfare agents. These simulants are characterized by relatively low toxicity levels and they have similar chemical structure to classes of chemical warfare agents standard gas chromatography and mass spectroscopy techniques. The task of this phase I effort was to prepare a comprehensive plan on how to make the system field portable, how to test the effectiveness of the unit against a full spectrum of chemical and biological warfare agents and how to optimize the proven system for battlefield use.
Download or read book Decontamination and Sterilization of Surfaces by Means of a One Atmosphere Uniform Glow Discharge Plasma written by and published by . This book was released on 2000 with total page 49 pages. Available in PDF, EPUB and Kindle. Book excerpt: Decontamination of surfaces that have been exposed to biological agents must be accomplished quickly under battlefield conditions. Current decontamination processes utilize corrosive solutions. which require careful handling and can damage the equipment that must be treated. A simple. fast-acting. and safe method for equipment decontamination would minimize equipment downtime and minimize the number of personnel needed. It has been demonstrated that exposure of microorganisms to gas discharge plasma reaction products leads to their destruction. In particular. an air stream. treated by the One Atmosphere Uniform Glow Discharge Plasma (OAUGDP). has been shown to destroy microorganisms in a time frame of tens of seconds. Simulants of biological agents coating surfaces similar to military equipment were exposed to the OAUGDP reactor under various operating parameters. Exposure time was the principal variable. The performance of the OAUGDP reactor applied to several types of microorganism was evaluated. All microorganisms used were destroyed within seconds to minutes of plasma exposure. The results indicate that the OAUGDP can be successfully used for military biological decontamination. The OAUGDP reactor is especially useful for the decontamination of sensitive equipment. which would be harmed by chemical washes.
Download or read book A Characteristic Study of the Atmospheric Pressure Nonthermal Resistive Barrier Plasma Discharge for Biological Decontamination written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Steady-state atmospheric pressure nonthermal plasmas can splendidly debilitate bacteria in liquids, gases and on surfaces, as well as can disintegrate hazardous chemicals. The nonthermal gas discharge at atmospheric pressure, such as resistive barrier discharge is investigated for low temperature sterilization purposes. In specific, exploring and understanding the hidden secrets of the plasma sterilization mechanisms and the intensification of the main microbial reduction pathways are the objectives of the research. A dual-mode steady-state atmospheric pressure resistive barrier ionized gas (plasma) generator has been designed and developed to meet the environmental health and federally mandated safety standards. Electrical, chemical, optical, and biological studies are carried out on the Steady-State, Atmospheric Pressure Resistive Barrier Discharge, with the intent of identifying the chemically and biologically active species produced. The goals of the research work are to prepare an effective, inexpensive plasma sterilization process and to identify and escalate the main contributing active species responsible for plasma sterilization. The effectiveness of ionized gases produced by the resistive barrier plasma discharge on sterilizing bacteria has been analyzed. Bacteria at a dilution that achieved a countable number of colonies were exposed or not exposed to ionized gases for various periods of time and monitored to determine the effects of ionized gas treatment.
Download or read book Decontamination Using a One Atmosphere Uniform Glow Discharge Cold Plasma written by and published by . This book was released on 2002 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atmospheric Glow Technologies is developing an innovative mobile atmospheric plasma decon system based upon the patented one atmosphere uniform glow discharge plasma (OAUGDP) technology. This advanced system will be a deployable military protection system that will decontaminate highly toxic chemicals and microorganisms on sensitive equipment, personnel protective equipment, and aircraft, vehicle, and shelter interiors. Phase I efforts demonstrated feasibility of the system in the neutralization of chemical warfare simulants (99.3% reduction). Phase II efforts will extend studies to biological warfare agents including spores, building upon the proven efficacy of the OAUGDP against a wide range of microorganisms. Future work will involve optimizing the system for recirculation of the airflow and air cooling. Studies are currently underway to determine the concentration of atmospheric plasma produced active species as well as the extent of chemical and biological degradation achieved. The system will also be tested for materials and device compatibility as well as neutralization studies of actual chemical and biological warfare agents.
Download or read book Plasma for Bio Decontamination Medicine and Food Security written by Zdenko Machala and published by Springer. This book was released on 2012-02-05 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-thermal (cold) plasmas at atmospheric pressure have recently found many breakthrough applications in biology, medicine, and food security. Plasmas can efficiently kill bacteria, yeasts, moulds, spores, biofilms and other hazardous microorganisms, including potential bio-terrorism agents. They can be employed for bio-decontamination and sterilization of surfaces, medical instruments, water, air, food, even of living tissues without causing their damage. Direct or indirect plasma interaction with living cells of microorganisms or even humans enables novel bio-medical applications, e.g. treatment of skin diseases and ulcers. Plasma-enhanced blood coagulation coupled with its antiseptic properties proved success in wound healing and opens new possibilities in surgery, emergency medicine and military applications. Plasma treatment allows cell manipulations, their removal and targeted transfer into the injured area, which can accelerate wound healing. Plasma induced apoptosis (programmed cell death) of tumor cells brings forth a great potential for cancer treatment. Besides, plasma enables painless treatment of dental caries, root canal disinfection, and other dentistry applications. This book is a selection of reviewed manuscripts issuing from the NATO Advanced Research Workshop Plasma for bio-decontamination, medicine and food security held in Jasná, Slovakia, on 15-18 March 2011. It provides a comprehensive overview of the current knowledge and research activities focused at the plasma applications in areas such as bio-decontamination, water chemistry, effects on cells; biofilm inactivation, UV sterilization, and medicine, especially tissue treatment and wound healing, as well as dentistry and food security.
Download or read book Atmospheric Pressure Plasma Cleaning of Contaminated Surfaces written by and published by . This book was released on 1999 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this project is to identify the key physics and chemistry underlying the use of atmospheric pressure plasmas for etching removal of actinides and actinide surrogates. This includes understanding of basic discharge mechanism at atmospheric pressure, gas and surface phase chemistry, and optimization and scale-up effort of atmospheric pressure plasma jet (APPJ).
Download or read book Atmospheric pressure Plasma Cleaning of Contaminated Surfaces 1998 Annual Progress Report written by and published by . This book was released on 1998 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The object of this research program is to develop an atmospheric-pressure plasma jet for converting transuranic wastes (TRUs) into low-level radioactive wastes (LLWs). This plasma process will be used to efficiently decontaminate a wide range of structures and equipment. This report summarizes work after 1 year and 9 months of a 3-year project. A picture of the atmospheric-pressure plasma jet is shown in Fig. 1. This new plasma source consists of two concentric electrodes through which a mixture of helium and reactive gases flow. The plasma is ignited by applying 13.56 MHz RF power to the inner electrode. The characteristics of this discharge are different from other atmospheric-pressure plasmas, such as transferred arcs, torches, coronas and silent discharges. Shown in Fig. 2 is the current-voltage curve for the plasma jet. Spark breakdown occurs at 0.01 A, and is proceeded by a normal glow region, in which the voltage remains constant with increasing current, and an abnormal glow region, in which the voltage increases rapidly with current. At about 1.0 A and 225 V, the plasma begins to arc. The normal glow region is rarely observed in atmospheric pressure plasmas. They usually proceed directly from spark breakdown to arcing. The trend shown in the figure indicates that the plasma jet is stable over a wide range of operating conditions. The distribution of reactive species in a plasma jet, containing oxygen and helium, has been characterized by Langmuir probe measurements, optical emission spectroscopy, and ultraviolet absorption spectroscopy. The charged particle density ranges from about 5 x 1011 cm−3 inside the plasma to 1 x 101° cm−3 in the jet exit. The concentration of metastable oxygen molecules (a 1 Dg and b 1 Sg) is estimated to be between 1012 to 1013 cm−3 . By contrast, the ozone concentration increases from about 5 x 1014 cm−3 inside the plasma to 1 x 1016 cm−3 in the effluent. The ozone molecules are produced by the reaction of O atoms with O2 molecules: O + O2 + M a O3 + M. To generate the amount of ozone observed, the O atom concentration in the plasma must be near 1 x 1016 cm−3, or about 10% of the oxygen fed. These results are quite unexpected, because most non-equilibrium, low-temperature plasmas achieve a much lower degree of dissociation. The etching of actinide metals has been simulated by using tantalum as a surrogate material. Tantalum etching rates of up to 1.2 mm/min are achieved with the plasma jet using a CF4/O2/He gas feed. This is 10 times faster than conventional plasma systems, and indicates that the atmospheric-pressure plasma is a promising technology for decontamination of DOE sites. Finally, the plasma jet has been successfully modified to process larger areas, up to about 1.0 ft2 . Work is underway to increase the process scale further. The authors are confident that this technology is capable of being adapted for decontamination operations in the field.
Download or read book Experimental Analyses of an Atmospheric Pressure Electrical Plasma Decontaminator written by Eric Pius Pradeep and published by . This book was released on 2006 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electrical Gas Plasmas have been widely utilized in the frontiers of sterilization and disinfection of hazardous chemicals and unsafe microorganisms. In this research Atmospheric Pressure Non-thermal Plasma has been employed using various working gases such as air, helium and nitrogen to study its decontamination effects. Focus is given to analyze the constituents of the plasma such as UV light, charged particles, and chemical components produced during the operation of the discharge which influences the incapacitation of the exposed entities, in this specific study, only bacteria and bacteriophages were exposed. Biological tests involved the cultivation of bacteria and bacteriophages on Petri dishes and their corresponding viability analysis after exposure to the plasma discharge, which was performed in an effort to realize the effectiveness of the treatment using the sterilizer. The results from the experiments were very encouraging in terms of debilitation, energy consumption and time requirements offering a comprehensive explanation of the efficiency of the sterilizer and its potential applications in various areas which includes military, medicine, post offices, hand sanitizers, recycling of hazardous wastes and many more. Use of Hydrogen Peroxide as a moistening agent in the discharge instead of water has yielded some astonishing results concerning the death rate of the microorganisms. Most importantly its prospect of being developed into a large scale medical sterilizer are reasonably high due to the fact that it does not need intricate operating regimes and therefore installing and operating the sterilizer will not require medical or engineering proficiency.
Download or read book Atmospheric Pressure Plasma Cleaning of Contaminated Surfaces written by Hans W. Herrmann and published by . This book was released on 2003 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this work is to demonstrate a practical, atmospheric pressure plasma tool for the surface decontamination of radioactive waste. Decontamination of radioactive materials that have accumulated on the surfaces of equipment and structures is a challenging and costly undertaking for the US Department of Energy. Our technology shows great potential for accelerating this clean up effort.
Download or read book Low Temperature Plasma for Biomedical Applications written by Mounir Laroussi and published by Frontiers Media SA. This book was released on 2023-11-09 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: Low-temperature plasmas (LTP) at atmospheric gas pressure play an increasing role in biomedical applications. The experimentally observed benefits of LTP for these applications are attributed to the controllable fluxes of chemically active species that can be produced in air at near room temperatures and delivered to bio-matter to induce desired effects. Recent research on the biomedical applications of LTP has generated new scientific knowledge regarding the interaction of plasma with soft matter including cells, tissues, seeds, and plants. The observed effects of LTP on biological cells are mediated by the plasma-produced reactive oxygen species (ROS) and reactive nitrogen species (RNS). These include hydroxyl, OH, atomic oxygen, O, singlet delta oxygen, O2(1Δ), superoxide, O2-, hydrogen peroxide, H2O2, and nitric oxide, NO. Some of these species are known to play important roles in biology serving as signaling molecules in living organisms. When they come in contact with biological cells these species interact with the lipids and proteins of the cell membrane, enter the cell and increase the intracellular ROS concentrations, which can lead to DNA damage and may compromise the integrity of other cell organelles. ROS and RNS can also trigger cell signaling pathways, which can lead to cellular death by apoptosis or necrosis. Other plasma-generated agents that could play biological roles are charged particles (electrons and ions), UV photons, and electric fields.
Download or read book Skin Decontamination written by Hanjiang Zhu and published by Springer Nature. This book was released on 2019-09-26 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: The skin is the first line of defense against chemical warfare agents including nerve agents and toxic industrial chemicals, providing a possible barrier or delay to systemic distribution. However, some chemicals act directly on the skin including vesicants sulfur mustard and corrosive compounds such as strong acids or bases, and do not have to gain access to systemic circulation to cause extensive skin damage. Early and rapid skin decontamination is extremely important following exposure to chemical warfare agents and toxic industrial chemicals because it decreases serious skin damage to the patient and, potentially, their doctor. This multi-authored international text pulls together a century of decontamination research and helps the reader expedite solutions that will decrease morbidity and mortality. Complete with dozens of hiqh quality photographs and illustrations, Skin Decontamination aids industrial hygiene, dermatology, occupational physicians and those involved in the public health arena.
Download or read book Encyclopedia of Agricultural Food and Biological Engineering written by Dennis R. Heldman and published by CRC Press. This book was released on 2010-10-21 with total page 2001 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examining the role of engineering in delivery of quality consumer products, this expansive resource covers the development and design of procedures, equipment, and systems utilized in the production and conversion of raw materials into food and nonfood consumer goods. With nearly 2000 photographs, figures, tables, and equations including 128 color figures the book emphasizes and illustrates the various engineering processes associated with the production of materials with agricultural origin. With contributions from more than 350 experts and featuring more than 200 entries and 3600 references, this is the largest and most comprehensive guide on raw production technology.
Download or read book Cold Plasma written by MDPI and published by MDPI. This book was released on 2021-01-20 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Non-equilibrium plasma (or low-temperature plasma, LTP) offers a chemically rich medium without the need for high power and elevated temperatures. This unique characteristic has made LTP very useful for various industrial and biomedical applications where thermal effects are not desirable. In addition, the relative simplicity of the design of sources capable of generating non-equilibrium plasma at atmospheric pressure makes LTP a very attractive technology that can accomplish the same or better results than much more complex and expensive approaches. This book describes various low-temperature plasma sources and some of their environmental and biomedical applications. The plasma sources covered in this book include low-temperature plasma jets which are novel devices that can launch low-power, low-temperature plasma plumes in ambient air. These plasma plumes can accurately and reliably be aimed at a surface to be treated or at a biological target such as cells and tissues. The application of these plasma jets in medicine, including in cancer therapy, are thoroughly discussed in this book. The contents of this book will appeal to engineers, medical experts, academics, and students who work with plasma technology.
Download or read book Atmospheric Pressure Plasma Cleaning of Contamination Surfaces 1997 Mid year Progress Report written by and published by . This book was released on 1997 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Goals of the project are to (1) identify the key physics and chemistry underlying the use of high pressure plasmas for etching removal of actinides and actinide surrogates; and (2) identify key surface reactions and plasma physics necessary for optimization of the atmospheric pressure plasma jet. Technical description of the work decommissioning of transuranic waste (TRU) into low-level radioactive waste (LLW) represents the largest cleanup cost associated with the nuclear weapons complex. This work is directed towards developing a low-cost plasma technology capable of converting TRU into LLW, based upon highly selective plasma etching of plutonium and other actinides from contaminated surfaces. In this way, only the actinide material is removed, leaving the surface less contaminated. The plasma etches actinide material by producing a volatile halide compound, which may be efficiently trapped using filters. To achieve practical, low-cost operation of a plasma capable of etching actinide materials, the authors have developed a y-mode, resonant-cavity, atmospheric pressure plasma jet (APPJ). In contrast to conventional, low pressure plasmas, the APPJ produces a purely-chemical effluent free of ions, and so achieves very high selectivity and produces negligible damage to the surface. Since the jet operates outside a chamber, many nuclear wastes may be treated including machinery, duct-work, concrete and other building materials. In some cases, it may be necessary to first remove paint from contaminated surfaces using a plasma selective for that surface, then to switch to the actinide etching chemistry for removal of actinide contamination. The goal of this work is to develop the underlying science required for maturation of this technology and to establish early version engineering prototypes. Accomplishments to Date The authors have made significant progress in this program. The work conducted jointly at Los Alamos and at UCLA. This has been facilitated by exchange of people, equipment and designs between the two locations. The study can be divided into three (3) components: (1) source design, operation and physics, (2) effluent characterization and analysis, (3) surface reactions and decontamination. Some of the key accomplishments in each area are noted.
