Browse Topic: Hazardous materials

Items (4,047)
ABSTRACT Discrete Particles are just as they sound, individual particles that represent Air, Soil and HE (High Explosives). They are not based upon a continuum theory and should not be confused with SPH (Smooth Particle Hydrodynamics) which is a full Lagrangian continuum theory. The modeling of Air, Soil and HE (High Explosives) with discrete particles requires millions of particles to accurately model the blast event. The innovation in software coupled with the advent of GPU Technology provides an efficient and robust solution to perform the analyses. Consider that the latest GPU processor, the Tesla K40, based upon NVIDIA Kepler™ Architecture, has 12 GB of GDDR5 memory and 2880 CUDA Cores. A standard workstation with an NVIDIA Tesla GPU is all that is required to perform the calculations and the benefits are a high degree of accuracy and simplified model setup. To demonstrate the use of Discrete Particles to model the blast event and show the effectiveness of GPU computing, the
Mindle, Wayne L.Gasbarro, Michelle D.Olovsson, Lars
This document is intended for connectors typically found on aerospace platforms and ground support equipment. The document provides the reasons for proper fiber optic cleaning, an in-depth discussion of available cleaning methods, materials, packaging, safety, and environmental concerns. Applicable personnel include: Managers Designers Engineers Technicians Trainers/Instructors Third Party Maintenance Agencies Quality Personnel Purchasing Shipping/Receiving Production
AS-3 Fiber Optics and Applied Photonics Committee
This document provides recommended best practice methods and processes for the in-service inspection, evaluation and cleaning of all physical contact (PC) fiber optic interconnect components (termini, alignment sleeves and connectors), test equipment and test leads for maintainers qualified to the approved aerospace fiber optic training courses developed in accordance with ARP5602 or ARINC807. This document also provides a decision-making disposition flowchart to determine whether the fiber optic components are acceptable for operation. For definitions of individual component parts refer to ARP5061
AS-3 Fiber Optics and Applied Photonics Committee
Passenger vehicles like buses tend to soak up heat when they are parked under an open sky. The temperatures inside the vehicle can get very high during daytime due to heating, which reduces the thermal comfort levels. All three modes of heat transfer, i.e., conduction, convection and radiation contribute to the heating process. Cool-down tests are performed to replicate this thermal behaviour and evaluate the time required for cooling the internal bus volume to comfortable temperatures. The phenomenon can also be analysed using CFD, and accounts of numerous such studies are available however, the effects of all three modes of heat transfer for practical application are rarely studied. In view of this, an effort has been made to develop a fast and reasonably accurate transient numerical method to predict the thermal behaviour of the cool-down process for a school bus cabin. The effects of all three modes of heating (conduction, convection, and solar radiation) have been evaluated, and
Sharma, ShantanuSingh, RamanandZucker, JamesMoore, Chris
This document provides guidance for oxygen cylinder installation on commerical aircraft based on airworthiness requirements, and methods practiced within aerospace industry. It covers considerations for oxygen systems from beginning of project phase up to production, maintenance, and servicing. The document is related to requirements of DOT-approved oxygen cylinders, as well to those designed and manufactured to standards of ISO 11119. However, its basic rules may also be applicable to new development pertaining to use of such equipment in an oxygen environment. For information regarding oxygen cylinders itself, also refer to AIR825/12
A-10 Aircraft Oxygen Equipment Committee
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
Researchers at Tufts School of Engineering have developed a method to detect bacteria, toxins, and dangerous chemicals in the environment with a biopolymer sensor that can be printed like ink on a wide range of materials — including wearables
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
Because they can go where humans can’t, robots are especially suited for safely working with hazardous nuclear waste. Now, scientists at the U.S. Department of Energy’s (DOE) Argonne National Laboratory have designed and tested a remote-controlled, dual-arm telerobotics system with human-like capabilities that has the potential to revolutionize hazardous waste clean-up and holds potential for broader applications
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
A novel method for Single Event Effect (SEE) Radiation Testing using Built-In Self-Test (BIST) feature of indigenously developed Vikram1601 processor is discussed. Using BIST avoids need of exhaustive test vectors to ensure test coverage of all internal registers and a physical memory to store test vectors. Thus, processor is the only element vulnerable to radiation damage during testing. In the first part, a brief introduction, need and methods of radiation testing of electronics especially SEE of radiation on Silicon based devices, different radiation effects, radiation damage mechanisms and testing methods are described. A brief introduction to Vikram1601 processor, the instruction – TST, used as BIST and testing scheme implementation using TST for studying the SEE is explained. Radiation test facilities are explained with respect to the types of testing possible, capabilities, radiation particle species and maximum energies possible, size limitations of Silicon under test and
Joseph, Dominic GeorgeDaniel, JojiK, PadmakumarL, JayalekshmyDevi, Athula
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
Remember that party where you were swinging glow sticks above your head or wearing them as necklaces? Fun times, right? Science times, too. Turns out those fun party favors are now being used by a University of Houston researcher to identify emerging biothreats for the United States Navy
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
Zhang, WeiQiu, ZizhenKong, ZhiguoHuang, XinWang, Fang
Determining occupant kinematics in a vehicle crash is essential when understanding injury mechanisms and assessing restraint performance. Identifying contact marks is key to the process. This study was conducted to assess the ability to photodocument the various fluids on different vehicle interior component types and colors with and without the use of ultraviolet (UV) lights. Biological (blood, saliva, sweat and skin), consumable and chemical fluids were applied to vehicle interior components, such as seatbelt webbing, seat and airbag fabrics, roof liner and leather steering wheel. The samples were photodocumented with natural light and UV light (365 nm) exposure immediately after surface application and again 14 days later. The review of the photos indicated that fabric type and color were important factors. The fluids deposits were better visualized on non-porous than porous materials. For example, blood was better documented on curtain airbags than side or driver airbags. Blood and
Boysen, KevinParenteau, ChantalToomey, DanielGregg, Richard H.
In radiography testing, the radioactive elements Iridium 192 (Ir192) and Cobalt 60 (Co60) are employed to detect subsurface and inner flaws. These radioactive components are kept secure within the radiation-protected source camera. Despite the fact that the camera is safe, there is a little quantity of radiation that may harm human body cells. In this present study, it restricts radiation emission by placing a lead sheet over the source camera, which absorbs the produced radiation. The innovative concept involves in this present work is to place a manually operated switch near the radiation source to emit radiation
Suresh Balaji, R.Daniel Das, A.Marimuthu, S.Manivannan, S.
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
The objective of this paper is to determine and design an optimized thermal management system for a solar electric four-wheeler while considering system influence. The major systems that will be analyzed and optimized include the HVAC, solar system, and battery. The HVAC system imposes a challenge to the designers to fulfill the passenger’s comfort and to operate it efficiently under a wide range of external loads from solar radiation, ambient temperature & and humidity, human metabolic activity, and other loads like the propulsion system temperature on the cabin. From the literature, it is found that the air conditioning system reduces on average 14% of the total battery capacity whereas the heating system reduces it by 18% [1], which makes the HVAC system design a crucial aspect to consider for the system influence. The battery car voltage changes significantly to meet the power demand and because of this, the battery system produces a large amount of heat while discharging which
Karthikeyan, Vikram RajGumma, Muralidhar
Corrosion affects all industrial sectors where metals or metal alloys are used in their structures. In the automotive industry, the continuous search for lightweight parts has increased the demand for effective corrosion protection, in order to improve vehicle performance without compromising durability and safety. In this scenario, coatings are essential elements to preserve and protect vehicle parts from various environmental aggressions. Automotive coatings can be classified into primers, topcoats, clearcoats, and specialty coatings. Primers provide corrosion resistance and promote adhesion between the substrate and topcoat. Topcoats provide color, gloss, and durability to the coating system, while clearcoats enhance the appearance and durability of the finish. Specialty coatings provide additional properties, such as scratch resistance, chemical resistance, and UV protection. In addition to these categories, there are the smart coatings, defined as those capable of modifying their
Vanzetto, Andrielen BrazNeves, GuilhermeAlves, Tamires PereiraMoura, João Henriquede Bortoli, Bruna FariasSantana, Leande Oliveira Polkowski, Rodrigo Denizarte
The phenomenon of liquid transfer in the liquid tank of the semi-trailer vehicle for transporting dangerous cargo (SVTDC) during braking is analyzed and the relevant mathematical model is established. The braking dynamic model of the SVTDC considering the liquid sloshing in the tank is established, and the model is verified based on the co-simulation method. Based on the typical conditions, the braking deceleration and axle load calculation functions of the model are simulated and analyzed, and the application prospect of the model in the development of driving automation control strategy is discussed
Li, GangyanZhao, RanFu, Teng
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
In the coming years, moving towards a hundred percent electric vehicles will be one of the key areas in the automotive industry. The main advantages of using e-mobility are operational flexibility, lower carbon emission and regenerative energy. Thermal management in an e-vehicle plays a vital role for the reliability of the system and any thermal failure can cost a significant amount of money to a company per vehicle. Inverter assembly is widely used to convert Direct Current (DC) to Alternating Current (AC) in the e-mobility platform to operate the motor for vehicle propulsion. It consists of various electronic transmitters, controllers, capacitors, and semi-conductors which will emit an enormous amount of heat during their operation. Since inverters are highly temperature sensitive in nature, it is necessary to improve the temperature distribution in the device. For this reason, adequate cooling system and ventilation is inevitable to keep the components operational. In this study
Govindarasu, AnbarasuT, SukumarSathyamoorthy, GugainamasivayamSubramanian, Vivek
The usage of asbestos-free material has grown in the automotive, aviation, and marine sectors due to its carcinogenic nature. The present investigation is to evaluate the non-asbestos organic friction material for automotive applications using aramid fibers. The aramid fibers or pulp is one of the essential ingredients of friction material as it possesses good qualities of friction material like high wear resistance and reliability. The present work is to optimize the pulp required for the best performance of friction lining material for brake pads in the automotive industry. The pulp percentage is varied by 0, 5, 7.5, and 10 weight percentages in hybrid composite friction materials. The various mechanical, wear and microstructural analysis are studied. The experimental result revealed that friction material having 10 wt% of aramid fiber (AF) proved the best performance with superior mechanical and wear characteristics
J, ChandradassT, ThirugnanasambandhamM, Amutha SurabiP, Baskara SethupathiRajendran, R
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
Currently, emission regulations for the LVs using standard spark ignited ICEs considering only gaseous pollutants, just as CO, HC and NOx. Following the upcoming legislation for personal vehicles sector, the LVs might also include limits of PN and PM. Regarding fuel injection strategies, the MPFI which was previously excluded from particulate control will be incorporated into the new regulation [1]. In terms of social harm, there will be a necessity to reduce engine particulate emissions, as they are known for being carcinogenic substances [2, 3, 4]. Generally, the smaller the particulate diameter, the more critical are the damages for human health therefore, the correct determination of PN and particulate diameter is essential. Beside future challenges for reducing and controlling particulates, the reduction of fossil fuel usage is also an imminent target, being the replacement by eFuels one of the most promising alternatives. Therefore, the particulate generation behavior of eFuels
Schurl, SebastianBatalha, GuilhermeKupper, MartinSchmidt, StephanKrasa, Helmut
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
MAHMUD, RizalTAKAHASHI, TatsukiKINOSHITA, HiroyukiSHIMIZU, FumikaNAGANAWA, ArenoMOROOKA, MasatoAIZAWA, Tetsuya
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
A presentation of work comparing efficacy of a traditional IR method used as a standard within the U.S. Army Combat Capabilities Development Command (DEVCOM) and by international collaborators with that of an emerging technology, cavity ring down spectroscopy (CRDS). Army Combat Capabilities Development Command, Aberdeen Proving Ground, MD A threat in the form of chemical vapor may not be visible, but rapid detection is critical for preservation of life and property. In addition, understanding the surrounding environment informs the posture that the warfighter will need to take. The field of chemical vapor detection spans far beyond the warfighter and is rich in research. A search in SciFinder for “chemical vapor detection” provides over 400,000 results with over 3,000 books, 26,000 reviews, and nearly 300,000 journal articles. The focus of this document will be with an eye towards perimeter monitoring for a wide range of gas-phase chemicals. To accomplish such sensing, compound
Upcoming legislation towards zero carbon emission is pushing the electric vehicle as the main solution to achieve this goal. However, electric vehicles still require further battery development to meet customer’s requirements as fast charge and high energy density. Both demands come with the cost of higher heat dissipation as lithium transport and chemical reaction inside the battery need to be performed faster, increasing the joule effect inside the battery. Due to its working principle, which guarantees an adiabatic environment, an accelerating rate calorimeter is used to study thermal phenomena in batteries like a thermal runaway. However, this equipment is not prepared to work with optical access, which helps to study and to comprehend battery surface distribution and other thermal aspects. This paper aims to show a methodology to correct temperature measurement when using a thermographic camera and optical access of sapphire in an accelerating rate calorimeter. The problem comes
Pastor, Jose V.Micó, CarlosLewiski, FelipeGolke, Diego
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
This specification covers a butyl (IIR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes
AMS CE Elastomers Committee
This specification covers requirements for producing brazed joints in parts fabricated from corrosion- and heat-resistant steels, carbon or low-alloy steels, or copper alloys, and the properties of such joints
AMS B Finishes Processes and Fluids Committee
This specification covers a cleaner in the form of a liquid
AMS J Aircraft Maintenance Chemicals and Materials Committee
This specification covers a water-soluble, oil-dispersing cleaner in the form of a liquid
AMS J Aircraft Maintenance Chemicals and Materials Committee
This specification provides requirements and procedures for hydraulic-pressure leak testing of parts
AMS B Finishes Processes and Fluids Committee
This specification covers nonfluorescent magnetic particles in the form of a mixed, ready-to-use suspension in an odorless oil vehicle and packaged in aerosol cans
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This specification covers nonfluorescent, magnetic particles having black, red, gray, or other color, as specified, supplied in the form of dry powders
AMS K Non Destructive Methods and Processes Committee
This procurement specification covers aircraft quality bolts and screws made from a low alloy, heat resistant steel of the type identified under the Unified Numbering System as UNS K14675
E-25 General Standards for Aerospace and Propulsion Systems
This SAE Standard specifies requirements for vulcanized rubbers in sheet form for use as standards in characterizing the effect of test liquids and service fluids. The appendices contain the standard reference elastomer formulas. The property changes of the SRE in contact with the indicated fluid under specified test conditions are the responsibility of the user. See 7.3 and Table 1. This standard is not designed to provide formulations of elastomeric product compositions for actual service
Committee on Automotive Rubber Specs
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
Gomes Lobato, Thiago HenriqueSottek, Roland
Community noise at vertiports is one of the most important questions related to upcoming urban air mobility (UAM) operations. While fixed-wing and/or fixed-rotor aircraft can mainly be treated by their changing operational parameters, such as rotor or propeller rpm, tilt-wing or tilt-engine configurations are more difficult to simulate because of their constantly changing noise emission and spatial radiation characteristics. The work presented in this paper is providing an overview of the noise situation at a virtual vertiport which is being approached and departed by a tilt-wing air-taxi in different ways. Several different departure procedures are simulated with the same generic air-taxi. For the noise emission semi-empiric methods were used. During the air-taxi’s descent and climb, different tilt configurations are included, mainly defined by the time dependent engine’s tilt-angle, but also related to different approach paths. Each approach or departure procedure is generating
Bauer, Michael
This specification covers a closed cell silicone rubber sponge in the form of sheet, strip, extrusions, and molded shapes
AMS CE Elastomers Committee
This specification covers a nitrile (NBR) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes
AMS CE Elastomers Committee
The author has been conducting research on UV based photocatalytic air purifier systems for the past 5 years to eliminate living organic germs, bacteria, pathogens, etc. from the cabin air. An HVAC system has been developed by using a filter impregnated by titanium di-oxide (TiO2) with UV lights to improve and maintain cabin air quality. The author has designed and constructed a 3rd generation HVAC unit for cabin air purification for automobiles that is based on UV photocatalytic process by using UV-C LEDs to eliminate viruses that typically exist in conditioned space. The author has conducted tests with HVAC unit to determine power consumptions of air purification systems. An HVAC unit that employs a HEPA (high efficiency particulate air filter) filter is compared with the same HVAC unit with UV & titanium dioxide based photocatalytic system. The pressure drops of the HEPA, particulate and TiO2 filters have been investigated that contribute to the overall energy consumption. The
Mathur, Gursaran
In recent years, the removal of lead (Pb), which is an environmentally hazardous material often used in bearings for automotive engines, has been continuously promoted. Bismuth (Bi) is attracting attention as a substitute for lead, and it is currently being used mainly for passenger cars and trucks as a lead replacement. However, lead has not been replaced for motorcycles where the bearings are exposed to high temperatures at high rotation speeds, and trucks and generators where high loading capacity, long lifetime and good corrosion resistance are required. It has been difficult to achieve both high load and corrosion resistant for a bearing overlay material. The purpose of this development is to improve the corrosion resistance and fatigue resistance of bismuth overlay by developing a bismuth- antimony alloy overlay in which antimony (Sb) is added to the bismuth matrix. However, concern arises that antimony may form a compound with copper (Cu) in the bearing alloy underneath the
Ando, AkiraKanaya, RyujiHaneda, Yuma
Currently the automotive industry has been under extremely important technological changes. Part of these changes are related to the way that users interact with the vehicle and fundamental components are the new digital cluster and screens. These devices have created a disruption in the way information is transmitted to the user, being essential for vehicle operation, including safety. Due to new operating conditions, multiple evaluations need to be performed, one of them is the solar temperature Load to ensure correct operation without compromising user safety. This test is required to identify the thermal performance on the screens mounted on the instrument panel. The performance identification is performed on both sides, analytical and physical. In regards finite element simulation it represents the solar chamber as the main source of heat and being the main mechanism of transmission the radiation. To model this boundary conditions, Taitherm® Software [1] is used, and it allows to
Alonso, LilianaSaavedra, Oscar
Army Research Laboratory, Adelphi, MD Developing single photon UV detection for compact chemical and biological sensors. This report summarizes the main lines of effort for the Electro-Optics Materials Research (EOMR) program including its goals and major accomplishments, focusing on the past 5 years. This EOMR program was an effort within 601102A.31B.1 titled “Optoelectronic and Integrated Photonic Materials and Device Research” for FY16-FY19 and 611102A.AA8.1 titled “Photonic Materials and Device Research” for FY20-FY21. The focus of this EOMR for most of the program was to develop novel semiconductor optoelectronic devices to reduce the size, weight, power, and cost (SWaP-C) of chemical and biological detection and identification systems. Specifically, the program addressed the need for high sensitivity photodetectors in the near-UV (NUV) spectrum between 300 and 350 nm for biological agent detection using light-induced fluorescence techniques employed by the Tactical Biological
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