Browse Topic: Radiation
In order to meet the demand for the transformation of traditional manufacturing industries into intelligent manufacturing, a virtual monitoring system for the production workshops of nuclear - key products has been built. There are problems such as poor environment, long distance and remote collaborative office in this production workshop, and managers lack information tools to master the workshop status in real time. In order to minimize the harm of nuclear radiation to the human body, in view of the problems of low transparency, poor real - time performance and low data integration in traditional two - dimensional forms, configuration software and video monitoring, a remote monitoring system for virtual workshops driven by digital models has been developed. This system realizes the remote dynamic display of real - time information in the workshop based on data collection and three - dimensional modeling technologies. Virtual monitoring technology improves the management efficiency of
Plastic materials are used for a wide variety of spacecraft applications including seals, bearings, fasteners, electrical insulators, thermal isolators, and radomes. Selecting plastics for use in space is complex due to wide operating temperature ranges, vacuum conditions, and exposure to radiation and atomic oxygen. Additionally, some spacecraft applications require sealing flammable propellants such as hydrogen and oxygen. This article will present some design considerations when selecting plastics for use in spacecraft. It will provide rich data on the performance characteristics of plastics as well as examples of successful spacecraft applications.
Researchers have developed a new type of sensor platform using a gold nanoparticle array. The sensor is made up of a series of gold disk-shaped nanoparticles on a glass slide. When an infrared laser is pointed at a precise arrangement of the particles, they start to emit unusual amounts of ultraviolet (UV) light.
This study presents a novel methodology for optimizing the acoustic performance of rotating machinery by combining scattered 3D sound intensity data with numerical simulations. The method is demonstrated on the rear axle of a truck. Using Scan&Paint 3D, sound intensity data is rapidly acquired over a large spatial area with the assistance of a 3D sound intensity probe and infrared stereo camera. The experimental data is then integrated into far-field radiation simulations, enabling detailed analysis of the acoustic behavior and accurate predictions of far-field sound radiation. This hybrid approach offers a significant advantage for assessing complex acoustic sources, allowing for quick and reliable evaluation of noise mitigation solutions.
Lead-filled aprons are currently used for atomic number (Z)-grade radiation shielding in the medical industry to protect personnel from hazardous gamma radiation. These apron garments are made with lead-filled elastomeric sheets encased in polymeric fabrics and are both heavy and bulky to meet necessary shielding requirements. In addition, there are environmental safety concerns surrounding disposal of these garments due to their lead content. An innovator at NASA Langley Research Center has developed a novel method for making thin, lightweight radiation shielding that can be sprayed or melted onto common textiles used in clothing such as cotton, nylon, polyester, Nomex, and Kevlar.
While DNA damage caused by space radiation exposure has long been recognized as a major threat to astronaut health, a recent study published in Redox Biology (Stolc et al., 2024) reveals an unexpected culprit in the atmosphere of the International Space Station (ISS) itself: elevated carbon dioxide (CO2) levels. In this study, mice were sent into space where they spent 5–6 week aboard the ISS.
X-rays are a common component of diagnostic testing and industrial monitoring, used for everything from monitoring your teeth to scanning your suitcase at the airport. But the high-energy rays also produce ionizing radiation, which can be dangerous after prolonged or excessive exposures. Now, researchers publishing in ACS Central Science have taken a step toward safer x-rays by creating a highly sensitive and foldable detector that produces good quality images with smaller dosages of the rays.
Spaceflight outside of the Earth’s protective magnetic field is dangerous from a cosmic radiation perspective. Inside Earth’s magnetic field, where the manned International Space Station (ISS) orbits, the radiation encountered is minimal and almost all is deflected by our planet’s magnetic fields. However, outside that protective shield, the Sun’s solar wind (high energy radiation, solar energetic particles or SEPs) consisting of protons, electrons, alpha particles, and plasmas continuously bombards the spacecraft for the months or years of spaceflight.
Radiation has garnered the most attention in the research that has been conducted on polyethylene sheets. According to the calculations, there were 145892.35 kGy in total radiation doses administered. An ultraviolet visible spectrophotometer was used to examine the impact that electron beam irradiation had on the optical constants. Two of the most crucial variables taken into account when calculating the optical constants and the absorption coefficient are the reflectance and transmittance of polyurethane sheets. Reduced light transmission through the sheet achieves these characteristics, which are related to the transmittance and reflectance of the Fresnel interface. Cross linking makes it more challenging for the polyurethane molecular chains to become fixed. Both the refractive index and the dispersion properties have been altered as a direct result of this. Despite the fact that the doses of electron irradiation were getting lower, it eventually rose to 105 kGy. Contrary to the
Researchers at the National Institute of Standards and Technology (NIST) and colleagues have developed standards and calibrations for optical microscopes that allow quantum dots to be aligned with the center of a photonic component to within an error of 10 to 20 nanometers (about one-thousandth the thickness of a sheet of paper). Such alignment is critical for chip-scale devices that employ the radiation emitted by quantum dots to store and transmit quantum information.
Advances in optical sensors and imaging technologies are ever more rapidly assimilated into how humans interact, understand themselves, and explore the world around them. The scope of inquiry for optical devices is broad and they enable technologies within, such as implanted transdermal bioMEMS devices, and beyond, or as space-flight surveyors deployed as near and deep space instruments. Central to the functionality of modern optical devices, ultra-narrow bandpass (UNBP) thin-film optical filters enable discrimination of sub-nanometer bands inside broad spectra. These filters, pioneered as NIR DWDM filters for the telecommunications industry, are now essential in extracting meaningful signal from imaging and sensing devices operating anywhere between the deep ultraviolet and the mid infra-red bands.
Sensor packaging, particularly for microelectromechanical systems (MEMS), is a critical aspect of modern electronics. MEMS developers have demonstrated a variety of innovative microsensors for almost every possible sensing modality including temperature, pressure, inertial forces, chemical species, magnetic fields, radiation, etc. While MEMS sensors are revolutionizing various industries with their precision and miniaturization, they can present unique product development challenges and risks during design, development, and manufacturing.
Northwestern University researchers have developed new devices based on a low-cost material to aid in the detection and identification of radioactive isotopes. Using cesium lead bromide in the form of perovskite crystals, the research team found that they were able to create highly efficient detectors in both small, portable devices for field researchers and in very large detectors. The results are more than a decade in the making.
Focused on the permanent magnet synchronous motor (PMSM) used in electric, this paper proposes an online insulation testing method based on voltage injection under high-temperature and high-humidity conditions. The effect of constant humidity and temperature on the insulation performance has been also studied. Firstly, the high-voltage insulation structure and principle of PMSM are analyzed, while an electrical insulation testing method considered constant humidity and temperature is proposed. Finally, a temperature and humidity experimental cycling test is carried out on a certain prototype PMSM, taking heat conduction and radiation models, water vapor, and partial discharge into account. The results show that the electrical insulation performance of the motor under constant humidity and temperature operation environment exhibits a decreasing trend. This study can provide theoretical and practical references for the reliable durability design of PMSM.
An international team of scientists reports a novel technique for a high-brightness coherent and few-cycle duration source spanning seven optical octaves from the UV to the THz.
Recent experiments by a team from the West Virginia University focused on how a weightless microgravity environment affects 3D printing using titania foam, a material with potential applications ranging from UV blocking to water purification. ACS Applied Materials and Interfaces published their findings.
Imagine being able to snap a picture of extremely fast events on the order of a picosecond. Compressed ultrafast photography (CUP) captures the entire process in real time and unparalleled resolution with just one click. The spatial and temporal information is first compressed into an image and then, using a reconstruction algorithm, it is converted into a video.
Most space satellites are powered by photovoltaic cells that convert sunlight to electricity. Exposure to certain orbit radiation can damage the devices, degrading their performance and limiting their lifetime. University of Cambridge scientists have proposed a radiation-tolerant photovoltaic cell design that features an ultrathin layer of light-absorbing material.
As a new method to examine the extremely unsteady and spatially varying wall heat transfer phenomena on diesel engine combustion chamber wall, high-speed imaging of infrared thermal radiation from the chromium coated window surface impinged by a diesel spray flame has been conducted in a constant volume combustion chamber. The infrared radiation from a back surface of the chromium layer was successfully visualized at 10kHz frame rate and 128 × 128 pixel resolution through the window. The distributions of infrared radiation, temperature and heat flux exhibited coherent and streaky structure with radial stripes extending and waving from a stagnation point likely reflecting the near-wall turbulent structure in a wall impinging diesel flame. The experiments were conducted with various parameters such as fuel injection pressure, ambient gas oxygen concentration, wall impinging distance, wall surface roughness and wall materials. Imaging velocimetry analysis was applied to the movement of
An ingestible x-ray dosimeter detects radiation dose in real time. Combining the novel capsule design and a neural network-based regression model that calculates radiation dose from the information captured by the capsule, researchers found that they could provide approximately five times more accurate monitoring of the dose delivered than current standard methods.
Space Dynamics Laboratory Utah State University North Logan, UT 435-713-3400
A wavelength of visible light is about 1,000 times larger than an electron, so the way the two affect each other is limited by that disparity. Now, researchers have come up with a way to make much stronger interactions between photons and electrons possible — in the process producing a hundred-fold increase in the emission of light from a phenomenon called Smith-Purcell radiation.
To empirically estimate the radiation of sound sources, a measurement with microphone arrays is required. These are used to solve an inverse problem that provides the radiation characteristics of the source. The resolution of this estimation is a function of the number of microphones used and their position due to spatial aliasing. To improve the radiation resolution for the same number of microphones compared to standard methods (Ridge and Lasso), a method based on normalizing flows is proposed that uses neural networks to learn empirical priors from the radiation data. The method then uses these learned priors to regularize the inverse source identification problem. The effects of different microphone arrays on the accuracy of the method is simulated in order to verify how much additional resolution can be obtained with the additional prior information.
Radiation shielding for space as well as some terrestrial applications is challenging due to the wide variety and energy ranges of radiation particles. NASA Ames has developed a novel technology that provides a new process for designing and accurately tuning radiation shields to possess the specific characteristics required for each application before testing, reducing the need for iterative radiation beam testing throughout the development process.
This paper takes the single-phase full-bridge power converter of the power generation system of the free-piston engine of the incremental electric vehicle (EV) as the research object. By establishing the three-dimensional (3D) electromagnetic radiation simulation model of the power converter, the electromagnetic radiation field of the power converter is simulated and analyzed by using the equivalent excitation source method. The shielding and suppression effect of the power converter shell on the far-field radiated electromagnetic field and its influence on the internal electromagnetic field are analyzed. The shielding cover of the radiation source and sensitive source of the power converter is designed, and the effectiveness of the electromagnetic radiation shielding device for shielding the radiation source and sensitive source is discussed. The simulation results show that the shell of the power converter can effectively shield the far-field radiation so that the external radiation
Astronauts who spend six months in space are exposed to roughly the same amount of radiation as 1,000 chest X-rays. Having multiple kinds of radiation bombard their bodies puts them at risk for cancer, central nervous system damage, bone loss, and some cardiovascular diseases. NASA funded research into a new method for measuring radiation damage to humans. Now, 19 years later, that fundamental science supports a diagnostic test to improve cancer treatment on Earth, called the OncoMate MSI Dx Analysis System.
UCSD San Diego, CA
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