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Railways operate in an open environment where temperature, humidity, and the oxidation conditions are subjected to change. An experimental investigation used a pin-on-disc machine to examine the influence of environmental conditions and iron oxides on the wear performance of the wheel-rail contact. The wear mechanisms were analyzed using scanning electron microscopy and found to be highly dependen
The coefficient of friction between railway wheels and rails is crucial to the railway adhesion, further greatly affecting railway operation and maintenance. Since the wheel-rail system is an open system, the coefficient of friction is significantly influenced not only by various types of contaminants but also by environmental conditions. This paper conducted a set of pin-on-disc tests measuring t
Aluminum matrix fly ash (AMFA) cenosphere composites were fabricated using the stir casting technique. The used type of fly ash cenosphere, which accounted for over 60% in all fly ash particles, was in narrow and small size (2-30 μm). During synthesis, effects of several key technological parameters on microstructure and properties were investigated using orthogonal experimental design. The optima
The effect of aluminum on microstructure and properties of martensitic wear-resistant and heat-resistant steels was investigated. The results indicate that as-cast microstructure of the specimens is composed of ferrite, pearlite and carbides. After quenching at 1,000 C and tempering at 600 C, the microstructure of the specimens consists of tempered sorbite and Fe-Cr-Al intermetallic compounds whic
Effect of aluminium on microstructure and properties of austenitic heat resistant steel was investigated. The results showed that Al addition led to formation of spheroidal and dispersed Ni3Al. After solution treatment, Ni3Al particles experienced a significant refinement from 1.5 μm to nanoscale (∼80 nm). Matrix transformed from austenite to ferrite when addition of Al was >4.72%. Oxidation resis
High-ductility ductile iron was alloyed with 0-1.8wt% Ni in this paper. The low-temperature impact toughness test and corrosion test of simulated seawater static whole-soaking were conducted to research the effect of nickel on the low-temperature impact toughness and corrosion resistance of high-ductility ductile iron. The results show that with nickel increasing, the impact toughness under low te
In this study, effect of tungsten on microstructure and properties of high chromium cast iron was investigated. The experimental results indicated that tungsten distributed uniformly in the matrix and carbides. W carbides are composed of WC1-x, W6C2.54 and CW3 and W2C. With the increase of tungsten content, bulk hardness and matrix microhardness both increased gradually and reached the peak at 62.
Autonomous vehicle is being developed for widespread deployment. Its reliability and safety are critically dependent on advanced wireless technologies, e.g., vehicle-to-everything (V2X) communication. The frontend of a V2X system needs an antenna module that enables the vehicle to reliably connect to all other networks. Designing V2X antenna is challenging due to the complex in-vehicle environment
Experimental governance is increasingly being implemented in cities around the world through laboratories, testbeds, plat- forms, and innovation districts to address a wide range of complex sustainability challenges. Experiments often involve public-private partnerships and triple helix collaborations with the municipality as a key stakeholder. This stretches the responsibilities of local authorit
Municipal leaders around the world are demonstrating significant interest in urban greening to realize a range of socioecological benefits. The urban greening toolkit often includes street trees, an essential component of urban design informed by historic legacies of both human and environmental factors. To date, there has been little comparative analysis of street tree density and distribution ac
Techno-politics is alive and well in cities of the twenty-first century, most prominently with the rise of smart cities and the digitalization of urban life but also in the myriad debates about climate and environment, social cohesion and democracy, and economic prosperity and well-being. This commentary uses the special issue on ‘Urban Techno- Politics’ as inspiration to reflect on three emerging
Conventional pastureland management has brought Southern Brazilian dairy farms to a financial and environmental crisis. In this context, the management-intensive grazing system (MIG) emerges as a viable alternative to conventional pastureland management. This study aims to analyze the Social-Ecological System (SES) transformation process of the dairy system in Santa Rosa de Lima, Southern Brazil,
Today’s smart city agendas are the latest iteration of urban sociotechnical innovation. Their aim is to use information and communication technologies (ICT) to improve the economic and environmental performance of cities while hopefully providing a better quality of life for residents. Urban planners have a long-standing tradition of aligning technological in- novation with the built environment a
A three-dimensional reactive multi-phase particle-in-cell (MP-PIC) model is employed to investigate biomass combustion and gasification in fluidized bed furnaces. The MP-PIC model considered here is based on a coarse grain method (CGM) which clusters fuel and sand particles into parcels. CGM is computationally efficient, however, it can cause numerical instability if the clustered parcels are pass
Exposure to airborne particles causes detrimental health effects, hence their assessment in indoor environments, where people spend most of the time, is important. The influence of energy renovation and occupants' activities on airborne particle concentrations was assessed in seven occupied Swedish residences. Ultrafine particle (UFP, <100 nm) number concentrations, PM2.5 (<2.5 μm) and black carbo
Background: Osteoporosis is an underdiagnosed and undertreated disease worldwide. Recent studies have highlighted the use of simple vertebral trabecular attenuation values for opportunistic osteoporosis screening. Meanwhile, machine learning has been used to accurately segment large parts of the human skeleton. Purpose: To evaluate a fully automated deep learning-based method for lumbar vertebral
Hydrothermal processes are an attractive clean technology and cost-effective engineering platform for biorefineries based in the conversion of biomass to biofuels and high-value bioproducts under the basis of sustainability and circular bioeconomy. The deep and detailed knowledge of the structural changes by the severity of biomasses hydrothermal fractionation is scientifically and technological n
Automatic methods for feature extraction, volumetry, and morphometric analysis in clinical neuroscience typically operate on images obtained with magnetic resonance (MR) imaging equipment. Although CT scans are less expensive to acquire and more widely available than MR scans, their application is currently limited to the visual assessment of brain integrity and the exclusion of co-pathologies. CT
We investigated the water sorption properties of macroporous cryogels of gelatine (Gel) and dextran dialdehyde (DDA) prepared via cryogelation at 260 K and following the freeze drying processes. Water vapour sorption isotherms for aerogels were studied at 293 K by two inde-pendent methods: static-gravimetric and dynamic vapour sorption (DVS) over a water activity range of 0.11–1.0. Experimental da
Highly efficient gas turbines are beneficial for improving the energy structure, reducing carbon dioxide emissions and protecting the Earth's environment. A highly efficient gas turbine means a higher inlet temperature and requires a more efficient cooling structure. Due to the limitations of aerodynamics, structure and strength, cracks, fractures and ablation easily form at the trailing edge of g
