Self‐Propelling and Positioning of Droplets Using Continuous Topography Gradient Surface

A radial pattern with continuous topography gradient is presented, which induces a continuous inward wettability gradient and enables self‐propelling and accurate positioning of droplets to the pattern center. The effect of droplet size and wettability gradient of the pattern on the self‐mobility of droplets is investigated. The wettability gradient is found to increase towards the pattern center, enhancing the self‐motion of droplets at the inner area of the pattern. Moreover, larger droplets give rise to a larger solid‐liquid contact diameter, which helps to satisfy the self‐motion criteria that the advancing contact angle at front edge is smaller than the receding contact angle at rear edge. Consequently, a larger droplet size favors self‐motion initiated from the outer area of the pattern. The continuous topography gradient employed here allows the flexible dispensing of droplets at any place within a certain range, and avoids potential pinning defects to droplets at geometrical discontinuities. An average self‐motion velocity up to 4.0 cm/s for microliter‐sized droplets is achieved on the resultant patterned surface.     

Characterization of Process Conditions in Industrial Stainless Steelmaking Electric Arc Furnace Using Optical Emission Spectrum Measurements

Emission spectroscopy is a potential method for gaining information on electric arc furnace (EAF) process conditions. Previous studies published in literature on industrial EAF emission spectra have focused on a smaller scales and DC arc furnaces. In this study emission spectrum measurements were conducted for 140t AC stainless steelmaking EAF at Outokumpu Stainless Oy, Tornio Works, Finland. Four basic types of emission spectra were obtained during the EAF process cycle. The first one is obscured by scrap steel, the second is dominated by thermal radiation of the slag, the third is dominated by alkali peaks and sodium D-lines and the fourth is characterized by multiple atomic emission peaks. The atomic emission peaks were identified by comparing them to the NIST database for atomic emission lines and previous laboratory measurements on EAF slag emission spectra. The comparison shows that the optic emission of an arc is dominated by slag components. Plasma conditions were analyzed by deriving plasma temperature from optical emissions of Ca I lines. The analysis suggests that accurate information on plasma conditions can be gained from outer plasma having a plasma temperature below 7000 K (6727 °C).     

Familial combined hyperlipidemia: detection and characterisation of the hyperlipidemic profile among children and adolescents

BACKGROUND: Familial combined hyperlipidemia is the commonest genetic form of hyperlipidemia among survivors of myocardial infarction and, therefore, its early detection is crucial for the prevention of coronary artery disease. The aim of the study was to establish the prevalence of hyperlipidemia in the offspring of affected families and to characterize their lipid, lipoprotein and apolipoprotein profile. PATIENT AND METHODS: Forty five subjects below the age of 19 were studied from which 30 were from affected families and 15 from healthy control families. Cholesterol and triglycerides in plasma, VLDL, IDL, LDL and HDL as well as apolipoproteins AI, B, C-II and C-III were measured. RESULTS: Hyperlipidemia was detected in 13 children (43%) from affected families. They also presented significantly elevated concentrations of cholesterol in plasma (p < 0.0001), LDL (p < 0.0001) and HDL (p < 0.05); triglycerides in plasma (p < 0.007), VLDL (p < 0.05) and LDL (p < 0.008), together with significantly increased concentrations of apolipoproteins AI (p < 0.02), B (p < 0.0004), C-II (p < 0.0005) and C-III (p < 0.03). No changes were observed in the IDL fraction. CONCLUSIONS: There is an elevated prevalence of hyperlipidemia among the offspring of patients with familial combined hyperlipidemia. On the contrary to that observed in adults, no alterations of the IDL fraction are present among affected children.     

Performance and programmability comparison of the thick control flow architecture and current multicore processors

The Journal of Supercomputing - Commercial multicore central processing units (CPU) integrate a number of processor cores on a single chip to support parallel execution of computational tasks....     

Color classification using color vision models

According to recent physiological research results, there are many individual differences already at the detection level of our color vision system. It is not completely clear yet, how the other levels of color vision system compensate the detection differences. Instead of detecting and analyzing colors exactly in the same way, we all just have learned to classify colors in a certain way, which seems to lead almost always to the same result independent of the individual differences in the color vision system. In this article, we experiment with four models developed for replicating certain properties of human color vision. We examine the color classification abilities of these models and show the differences and similarities in their behavior. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010.     

Control of reflux and reboil flow rates for milli and micro distillation

An accurate control of reflux and reboil flow rates for small scale distillation unit has been evaluated. Its feasibility was studied with a distillation column with good results. The distillation column was planar in shape, and it was operated in a horizontal orientation. Porous, open-cell metal foam was used as the column packing. The distillation unit could be operated at extremely low mass fluxes. The operation of the distillation unit was extremely stable, which was achieved thanks to the rigorous control of the fluid flow rates, and heat losses. The heat loss model was regressed based on distillation experiments with total reflux, and the model was used to optimize the temperature of the column shell in order to minimize the heat losses from the column. The volume of the reboiler, the preheaters, and the heat exchangers was minimized with the use of flat channels for intensified heat exchange. The total liquid holdup of the system was less than 40 cm³. The efficiency of the distillation unit was characterized for two binary and one ternary system.     

Assessment of pitting corrosion in bare and passivated (wet scCO2-induced patination and chemical passivation) hot-dip galvanized steel samples with SVET,FTIR, and SEM (EDS)

In this study, the local electrochemical activity of untreated and passivated (natural or chemical passivation) zinc specimens was observed during immersion in a 0.1-M NaCl solution. The localized anodic activity during the exposure, measured with the scanning vibrating electrode technique, was linked to zinc dissolution by the pitting corrosion mechanism. It was correlated to specific corrosion products characterized by Fourier transmission infrared (FTIR) microscopy. FTIR molecule maps were produced from individual pitting corrosion sites (100–200 µm in width). With argon ion beam milling and latest energy-dispersive X-ray spectroscopy (EDS) technology, element maps with a high spatial resolution (≪100 nm) were recorded from abrasion- and beam-sensitive corrosion products, showing a residual layer structure. This study demonstrates the capability of FTIR mapping, cross-section polishing, and state-of-the-art scanning electron microscopy imaging, and EDS element mapping to produce high-resolution elemental, molecular, and visual information about pitting corrosion mechanisms on a hot-dip galvanized steel sample.     

Particle Entrapment in Hybrid Lubricated Point Contacts

This study proposes an innovative approach for the study of particle entrapment in rolling element bearings (REBs). Two couples of contacting materials were considered, the classical steel–steel and silicon nitride–steel used in hybrid bearings. Numerical simulations, as well as experiments, combine theoretical trajectories for incoming contaminant particles and effective entrapment ratios observed within a twin-disc machine. Linking both approaches allows the highlighting of some key parameters leading to particle entrapment under pure rolling conditions in elastohydrodynamic point contacts.