Effect of annealing time on solute carbon in ultralow-carbon Ti-V and Ti-Nb steels

The influence of annealing temperature and time on solute carbon levels was investigated in four ultralow-carbon (ULC) bake-hardenable steels; two Ti-V ULC steels with different V/C levels and two Ti-Nb ULC steels with different Nb/C levels. Internal-friction and scanning transmission electron microscopy (STEM) techniques were used to understand the precipitation/dissolution behavior in the various steels. An effect of annealing time on the carbon Snoek-peak height was observed in both Ti-V steels and in the Ti-Nb steel having a lower Nb/C ratio. Despite differences between these steels resulting from their composition (and, thus, carbide solubility) differences, after cold rolling and annealing at different temperatures, the maximum Snoek-peak height was achieved after annealing for shorter times in each instance, on the order of 1 minute. The highly stabilized Ti-Nb ULC steel with a higher Nb/C ratio did not show the effect because of the absence of solute carbon. For the Ti-V steels, most of the precipitates examined using STEM contained both Ti and V. The energy-dispersive X-ray (EDX) analysis indicated that both the Ti-V steels annealed at 845 °C for 1 minute have greater Ti/V ratios compared to their corresponding Ti-V steels in the as-received (hot-rolled) condition. This behavior is consistent with dissolution of carbides causing the carbon in solution to increase, as indicated by a greater carbon Snoek-peak height for both Ti-V steels in the annealed condition. The reduction in Snoek-peak height at longer annealing times is believed to be associated with segregation to lower-energy defect sites.     

Early bankruptcy prediction using ENPC

Bankruptcy prediction has long time been an active research field in finance. One of the main approaches to this issue is dealing with it as a classification problem. Among the range of instruments available, we focus our attention on the Evolutionary Nearest Neighbor Classifier (ENPC). In this work we assess the performance of the ENPC comparing it to six alternatives. The results suggest that this algorithm might be considered a good choice.     

Ubiquitin Ligases in Longevity and Aging Skeletal Muscle

The development and prevalence of diseases associated with aging presents a global health burden on society. One hallmark of aging is the loss of proteostasis which is caused in part by alterations to the ubiquitin–proteasome system (UPS) and lysosome–autophagy system leading to impaired function and maintenance of mass in tissues such as skeletal muscle. In the instance of skeletal muscle, the impairment of function occurs early in the aging process and is dependent on proteostatic mechanisms. The UPS plays a pivotal role in degradation of misfolded and aggregated proteins. For the purpose of this review, we will discuss the role of the UPS system in the context of age-related loss of muscle mass and function. We highlight the significant role that E3 ubiquitin ligases play in the turnover of key components (e.g., mitochondria and neuromuscular junction) essential to skeletal muscle function and the influence of aging. In addition, we will briefly discuss the contribution of the UPS system to lifespan. By understanding the UPS system as part of the proteostasis network in age-related diseases and disorders such as sarcopenia, new discoveries can be made and new interventions can be developed which will preserve muscle function and maintain quality of life with advancing age.     

Probing the electromagnetic field distribution within a metallic nanodisk

A Co nanolayer is used as a local probe to evaluate the vertical inhomogeneous distribution of the electromagnetic (EM) field within a resonant metallic nanodisk. Taking advantage of the direct relation between the magneto-optical activity and the electromagnetic field intensity in the Co layer, it is shown that the nonuniform EM distribution within the nanodisk under plasmon resonant conditions has maximum values close to the upper and lower flat faces, and a minimum value in the middle.     

Self-deflection of Three-dimensional Optical Beams by a Thin Nonlinear Layer with Saturable Dispersive and Absorptive Nonlinearity

Abstract

This paper describes self-deflection effects arising from the propagation of symmetric and asymmetric three-dimensional scalar optical beams through thin nonlinear layers. The model of nonlinearity used includes both saturation and absorption. In several cases, significant differences are observed between the present three-dimensional results and previous two-dimensional results based on the Kerr model of nonlinearity. Also, the existence of a large axial component of the self-deflected beam for a three-dimensional geometry against the absence of this component for a two-dimensional geometry is discussed.     

Assessment of Mineralogical,Textural, and Water Chemistry Changes During Long-Distance Tailings-Slurry Transport

An exploratory study demonstrated that subtle changes in solids and process water were caused by long-distance turbulent transport of tailings from the concentrator to the impoundment of a Cu (Mo) porphyry copper deposit. Slurry water chemical analysis was complemented by modelling potential phase precipitation or dissolution and speciation of dissolved metals. It was found that transport did not affect major insoluble mineral phases. However, the degrees of liberation of several phyllosilicates, as determined by automated mineralogy, were reduced close to the impoundment, which points to separation of clay particles from tectosilicate surfaces by the turbulence; this also was observed by SEM examination of micro-aggregate specimens. Reduction of maximum particle sizes, increased N2 monolayer adsorption, and resultant specific surface areas indicate that transport modified the micro-aggregates. Major element water chemistry is controlled by the presence of soluble mineral phases, such as gypsum, and reagents, such as lime, in the flotation process. Changes in the dissolved concentrations of some elements could potentially affect tailings deportment in the impoundment. Increased concentrations of Al may affect the clay settling behaviour, while Mo and As levels will require treatment prior to the discharge of water from the tailings impoundment. This study demonstrated that systematic scrutiny of tailings slurries leaving the concentrator and before entering the impoundment can be potentially useful, though care will have to be exercised to replicate sample handling and analytical conditions, during any long-term monitoring.     

Design of reflectors which will distribute sunlight in a specified manner

A differential equation is obtained for the shape of a reflecting surface which will distribute axially symmetric light intensity into a specified irradiance over a receiver surface which is symmetric about the direction of the incident light. Results are applied to the design of rotationally symmetric solar reflectors and also to a 2-dimensional geometry, that is one in which the reflector is a cylinder with its axis perpendicular to the incident beam. The procedure is used to numerically calculate the shape of reflectors which will uniformly concentrate collimated light and also light from a point source over a flat receiver surface. Results are also applied to determine the shape of a reflector which will distribute collimated light uniformly over the surface of a cylinder and also over a sphere.     

Lateral Thermal Diffusion Effects on Photothermal Signals from Photovoltaic Cells

Thermal diffusion, parallel to the photovoltaic junction and perpendicular to the direction of illumination, can be used to separate the contributions of injected and photogenerated carriers to the generation of heat in a photothermal experiment, and to demonstrate the influence of electronic carrier diffusion on the signal, already at relatively low modulation frequencies. We show this by using an experimental arrangement in which the distance is varied between the illuminated area of the photovoltaic cell and that over which the thermal signal is detected, and the two areas do not overlap. Our results agree with theoretical calculations used to simulate the photothermal responses of solar cells.     

Varistor Ceramics

The development of varistor ceramics is reviewed with an emphasis on ZnO-based varistors formed by liquid-phase sintering. Particular attention is given to the effects of microstructural disorder on the properties of varistors and to the different modes of failure that can occur.