SEARCH · Engineering Papers
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Decontamination of spacecraft components with ethylene oxide as function of parameters of gas concentration, time, temperature, and relative humidity
Mathematical models for microorganism exponential die-off rate and variance estimation from decontamination data
Truckloads of materials such as rare books, papers, engineering drawings, blue prints, art work, leather objects such as shoes, and clothing were successfully dried, decontaminated and impregnated against future infestation by microorganisms in a large 12 x 24 foot vacuum chamber designed originally for testing unmanned spacecraft. The process is unique in that it allows either frozen or wet material, soaked by some castastrophic event to be dried and sterilized in the same chamber with a minimum of handling and transportation.
Recent technical advances made in the field of sterilization and decontamination and their applicability to private and commercial interests are discussed. Government-sponsored programs by NASA produced the bulk of material presented in this survey. The summary of past and current research discussed is detailed to enhance an effective transfer of technology from NASA to potential users.
Nonlinear mathematical models of a rotor system, referred to as rotating blade-element models, produce steady-state, high-frequency harmonics of significant magnitude. In a discrete simulation model, certain of these harmonics may be incompatible with realistic real-time computational constraints because of their aliasing into the operational low-pass region. However, the energy is an aliased harmonic may be suppressed by increasing the computation rate of an isolated, causal nonlinearity and using an appropriate filter. This decontamination technique is applied to Sikorsky's real-time model of the Black Hawk helicopter, as supplied to NASA for handling-qualities investigations.
Most propulsion systems are designed to be filled and flown, draining can be done but decontamination may be difficult. Transport of these systems may be difficult as well because flight weight vessels are not designed around DOT or UN shipping requirements. Repairs, failure analysis work or post firing inspections may be difficult or impossible to perform due to the hazards of residual propellants being present.
A system for decontaminating a medium. The system can include a medium having one or more contaminants disposed therein. The contaminants can be or include bacteria, fungi, parasites, viruses, and combinations thereof. A microwave energy radiation device can be positioned proximate the medium. The microwave energy radiation device can be adapted to generate a signal having a frequency from about 10 GHz to about 100 GHz. The signal can be adapted to kill one or more of the contaminants disposed within the medium while increasing a temperature of the medium by less than about 10 C.
A system for decontaminating a medium. The system can include a medium having one or more contaminants disposed therein. The contaminants can be or include bacteria, fungi, parasites, viruses, and combinations thereof. A microwave energy radiation device can be positioned proximate the medium. The microwave energy radiation device can be adapted to generate a signal having a frequency from about 10 GHz to about 100 GHz. The signal can be adapted to kill one or more of the contaminants disposed within the medium while increasing a temperature of the medium by less than about 10 C.
Plant growth research for food production at Kennedy Space Center looks at how future residents of Mars and the Moon will enjoy the sight, smell, taste, and nutrition of plants. Overall, the goal is to provide a sustainable source of healthy food, on long-duration space flights, so astronauts can get the nutrition they need and produce food. The sustainable production of food will aid in the efforts of closed life support. Plants have a vital application for bio regenerative life support as demands for food and oxygen can be provided through photosynthesis, while the carbon dioxide from human respiration is removed. Transpiration is also used in life support processes as waste water that can be recycled through plant systems with the resultant humidity then condensed as clean water. Selected crops will provide the nutrient requirements needed for long duration space flight. Currently, projects in food production are investigating how plants grow in Martian regolith simulant, new crops testing with tomato and pepper cultivars, acquiring real-time photosynthetic data on crops, assessing plant growth in porous concrete media, and the use of plasma for surface decontamination of seeds.
Radiation detectors and methods of using the radiation detectors that provide a route for surface decontamination during use are described. The detectors utilize light illumination of an internal surface during use. Light is in the longer UV to near-infrared spectra and desorbs contamination from internal surfaces of radiation detectors. The methods can be carried out while the detectors are in operation, preventing the appearance of the negative effects of radioactive and non-radioactive contamination during a detection regime and following a detection regime.
Radiation detectors and methods of using the radiation detectors that provide a route for surface decontamination during use are described. The detectors utilize light illumination of an internal surface during use. Light is in the longer UV-to-near-infrared spectra and desorbs contamination from internal surfaces of radiation detectors. The methods can be carried out while the detectors are in operation, preventing the appearance of the negative effects of radioactive and non-radioactive contamination during a detection regime and following a detection regime.
Not Available
A lack of N95 Filtering Facepiece Respirators (FFRs) during the COVID-19 crisis has placed healthcare workers at risk. It is important for any N95 reuse strategy to determine the effects that proposed protocols would have on the physical functioning of the mask, as well as the practical aspects of implementation. Here we propose and implement a method of heating N95 respirators with moisture (85°C, 60-85% humidity). We test both mask filtration efficiency and fit to validate this process. Our tests focus on the 3M 1860, 3M 1870, and 3M 8210 Plus N95 models. After five cycles of the heating procedure, all three respirators pass both quantitative fit testing (score of >100) and show no degradation of mask filtration efficiency. We also test the Chen Heng V9501 KN95 and HKYQ N95 finding no degradation of mask filtration efficiency, however even for unheated masks these scored <50 for every fit test. The heating method presented here is scalable from individual masks to over a thousand a day with a single industrial convection oven, making this method practical for local application inside health-care facilities.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
This paper describes laser cleaning of contaminated tools in a nuclear power facility in Chalk River, Ontario Canada and also the same for EnergySolutions facility in Memphis facility. For the Chalk River facility, other methods of cleaning which included dry ice blasting, disassemble and wipe clean and steam cleaning, generated secondary waste and were time consuming. Laser cleaning of the tools in facility did not create secondary waste, was more efficient and safer for the operator. The laser cleaning method was compared with other methods. For the EnergySolutions facility in Memphis, laser cleaning was compared with hands on cleaning and laser removal by applying them to a rail car, a metal plate and a metal skate. (authors)
The treatment of radioactive wastewater from the operating nuclear industry (energy production, reprocessing of spent fuel, decommissioning of shut-down facilities, etc.) or in case of incidental or accidental situation (such as Fukushima Daichii NPP accident) is an important issue requiring constant improvement of the technologies and techniques used to prevent radioactive releases into the environment and/or to reduce the production of secondary waste. CEA, Orano and CTI are collaborating since 2014, with the support of the French government's program 'investments for the future', to develop Sorbmatech{sup R}Cs, an innovative and patented selective sorbent (Grandjean and Barre 2014) to deal with the removal of radioactive {sup 137}Cs, one of the most hazardous isotope to be managed in nuclear waste, highly efficient either in agitated reactor or in column process. Sorbmatech{sup R}Cs sorbent consists of mesoporous silica particles loaded with potassium-copper hexacyanoferrate nanoparticles (KCu-HCF). This peculiar structure enables much faster sorption kinetics compared to denser crystalline structures, such as Silicotitanate or Zeolite sorbents, whose drawback consists in hindering the diffusion process through the material, and whose larger sorbent particles slow down the ion exchange process. The equilibrium of Sorbmatech{sup R}Cs is reached in few minutes, even at high flow rates in a fixed-bed column process (up to 10 m.h{sup -1} Darcy velocity) with low drop pressure. Moreover, Sorbmatech{sup R}Cs can be used over a wide pH range from 2 to 10 and has a very high selectivity towards {sup 137}Cs even in brine solution (saline, mineral or sea water). This new sorbent also has a K{sub d} higher than 10{sup 5} mL.g{sup -1} depending on the salinity of the wastewater, enabling a highly efficient removal of Cs trace in radioactive wastewater compared to Cs selective sorbent such as Zeolites and Silicotitanates. Its radiological resistance enables the treatment of high, medium and low activity wastewater. The CEA-Orano-CTI/ALSYS partnership leads to the development of a simple and low-cost synthetic route, which demonstrated large-scale manufacturing of the product on a batch of 100 kg. Two products have been developed and are ready for short run market introduction so far with grain size well adapted either for column processes or agitated reactors.. Finally, the industrial implementation has been studied and largely benefits from the properties of the sorbent. Indeed, its high sorption kinetics enable high flow rates resulting in a decrease of operation times, unit sizes, and volumes of secondary waste produced. Moreover, Sorbmatech{sup R}Cs is designed to be combined into a full and integrated solution, ranging from preliminary optimization of operating conditions through numerical dimensioning model, industrial implementation and treatment of the wastewater (through cartridge or preconditioned columns systems developed thanks to Orano's extensive expertise), to long-term stabilization of generated waste (under progress). (authors)
After the Fukushima Daiichi NPP accident, a large area of East Japan was contaminated by radio-Cs. To discuss the final disposal of the contaminated wastes off-site and the required development of related technologies, it is important to understand the volume and radiation concentration of the wastes after various treatments. For a scientific investigation purpose, a research committee has been formed by the Society for the Remediation of Radioactive Contamination in the Environment, which is independent from the Ministry of Environment. This committee's work is focused on discussing various scenarios for the final disposal considering a mass balance evaluation of the entire process, economic evaluations, and stakeholder consultation for final consensus. The current discussions of this committee are herein reported. (authors)