In-service diesel engines are a significant source of particulate matter (PM) emissions, and they have been subjected to increasingly strict emissions standards. Consequently, the wide-scale use of some type of particulate filter is expected. This study evaluated the effect of an Engelhard catalyzed soot filter (CSF) and a Rypos electrically heated soot filter on the emissions from in-service diesel engines in terms of PM mass, black carbon concentration, particle-bound polycyclic aromatic hydrocarbon concentration, and size distribution. Both filters capture PM. The CSF relies on the engine's exhaust to reach the catalyst regeneration temperature and oxidize soot, whereas the electrically heated filter contains a heating element to oxidize soot. The filters were installed on several military diesel engines. Particle concentrations and compositions were measured before and after installation of the filter and again after several months of operation. Generally, the CSF removed at least 90% of total PM, and the removal efficiency improved or remained constant after several months of operation. In contrast, the electrical filters removed 44-69% of PM mass. In addition to evaluating the soot filters, the sampling team also compared the results of several real-time particle measurement instruments to traditional filter measurements of total mass.
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http://dx.doi.org/10.1080/10473289.2004.10470884 | DOI Listing |
Sci Rep
January 2025
School of Instrumental Science and Engineering, Harbin Institute of Technology, 150001, Harbin, People's Republic of China.
In this study, a method for predicting the thermal shock life of coatings is proposed, and a model for predicting the thermal shock life of coatings based on high temperature thermal shock life test and three-dimensional heat transfer analysis is established. Firstly, the thermal shock life of coatings at different cooling and heating cycle temperatures is obtained through a designed thermal shock life testing device for silicide coatings at a wide-temperature range from 500℃ to 3000℃. Secondly, the actual thickness of the coating and the continuous oxidation in the thermal shock life test are taken into consideration.
View Article and Find Full Text PDFSmall
January 2025
Department of Chemistry, Indian Institute of Technology-Guwahati, Guwahati, Assam, 781039, India.
The design of electrically conductive textiles appears to be a promising approach to combat the existing challenge of deaths caused by severe cold climates around the globe. However, reports on the scalable fabrication of tolerant conductive textiles maintaining a low electrical resistance with an ability for unperturbed and prolonged performance are scarce. Here, a breathable and wrappable water-repellent conductive textile (water-repellent CT) with electrothermal and photothermal conversion abilities at low external voltage and in weak solar light is introduced, respectively.
View Article and Find Full Text PDFHeliyon
January 2025
Department of Environmental Science & Engineering, Ewha Womans University, South Korea.
A path to carbon neutrality requires the development of refrigeration units that use no refrigerant or emit less greenhouse gas (GHG), such as Thermoelectric coolers (TECs). Using the life cycle inventory assessment (LCIA), the environmental impacts of the manufacturing process of TECs were analyzed, including greenhouse gas emissions, human carcinogenic toxicity (HCT), terrestrial ecotoxicity (TE), freshwater ecotoxicity (FE), mineral resource scarcity (MRS), and fossil resource scarcity (FRS). The alumina plate manufacturing process produces the most GHG emissions because it uses a lot of electricity in the sintering process.
View Article and Find Full Text PDFHeliyon
January 2025
Department of Mechanical Engineering, Faculty of Engineering, Arak University, Arak 38156-88349, Iran.
This research presents a numerical study over the unsteady natural convection of an electrically conducting fluid in an open-ended vertical parallel plate microchannel under uniform and asymmetric heat flux subjected to a uniform lateral magnetic field. Slip velocity, as well as temperature jump at channel walls, are modeled using a first-order model. The effects of Knudsen number)(, heat flux ratio)rq(, Grashof number)(, and Hartmann number)M(on mass flow rate, the maximum temperature of the wall, and average Nusselt () as a function of time are discussed.
View Article and Find Full Text PDFNat Commun
January 2025
Institute of Humanoid Robots, School of Engineering Science, University of Science and Technology of China, Hefei, 230026, China.
A human hand has 23-degree-of-freedom (DOF) dexterity for managing activities of daily living (ADLs). Current prosthetic hands, primarily driven by motors or pneumatic actuators, fall short in replicating human-level functions, primarily due to limited DOF. Here, we develop a lightweight prosthetic hand that possesses biomimetic 19-DOF dexterity by integrating 38 shape-memory alloy (SMA) actuators to precisely control five fingers and the wrist.
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