Corrosion and wear characteristics of pulse-plated chromium deposits

Corrosion and wear characteristics of pulse-plated chromium deposits, obtained from a self-regulating highspeed (SRHS) bath have been studied as a function of pulse current parameters such as duty cycle, average current density and pulse period. The chromium deposits obtained at duty cycles of 100 (direct current) to 60% were composed of a hemispherical nodular growth with a body centred cubic (b c c) lattice while those obtained at 20% duty cycle were composed of a needle-like structure containing a mixture of b c c lattice and hexagonal hydride. Corrosion rate, wear loss of chromium deposits and occluded hydrogen content in the deposits decreased up to 60% duty cycle, and then increased with further decrease in duty cycle to 20%. A two-stage variation of corrosion and wear properties with decreasing duty cycle is discussed in terms of crack density and the crystal structure of chromium deposits.     

In vitro and in vivo anti-inflammatory activities of mixed fruit and vegetable juice

Food Science and Biotechnology - In this study, we attempted to develop fruit-based functional juice with anti-inflammatory activity for consumers living under heavy air pollution. At first, four...     

Characterization of biofilm structure and its effect on membrane permeability in MBR for dye wastewater treatment

Two membrane bioreactors were operated at aerobic (DO=6.0mg/L) and anoxic (DO<0.3mg/L) conditions for the treatment of synthetic dye wastewater to determine the effect of dissolved oxygen on membrane filterability. The rate of membrane fouling for the anoxic MBR was five times faster than that for the aerobic MBR. Differences in the nature of the biofilm that was formed on the membrane surface as the result of different DO level was the main factor in the different fouling rates. The biofilm structure was characterized using digital image analysis techniques. Biofilm images were obtained using confocal laser scanning microscopy (CLSM) at various operation points. Structural parameters were then computed from these images using an image analysis software (ISA-2). The structural parameters indicated that the anoxic biofilm was thinner than the aerobic biofilm but the anoxic biofilm was spread out on the membrane surface more uniformly and densely, resulting in the higher membrane fouling. Based on the extracellular polymeric substances (EPS) visualization and quantification, it was also found that EPS, key membrane foulants were spread out more uniformly in the anoxic biofilm in spite of lower amount of EPS compared to that in the aerobic biofilm.     

A study on the rapid bulk combustion of premixture using the radical seeding

The objective of this study is the rapid bulk combustion of mixture in a constant volume chamber with a tiny sub-chamber. Some narrow passage holes were arranged to induce simultaneous multi-point ignition in the main chamber by jet of burned and unburned gases including radicals from the sub-chamber, and the equivalence ratios of pre-mixture in the main chamber and the sub-chamber were the same. The principal factors of the Radical Induced Auto-Ignition (RIAl) method are the diameter of the passage holes and the volume of sub-chamber. The relationship between the sub-chamber and diameter of passage hole was represented by the ratios of sub-chamber volume to passage hole volume. The ratios are non-dimensional coefficients for sub-chamber characteristics. As a result, the RIAI method reduced the combustion period, which expanded the lean limit in comparison with SI method.     

Soy products fermented with sprouted garlic have increased neuroprotective activities and restore cognitive functions

Food Science and Biotechnology - Enhanced antioxidant activities of sprouted garlic over garlic were considered. The popular Korean traditional fermented soybean product cheonggukjang (CGJ) was...     

A 0.18-/spl mu/m CMOS 3.5-gb/s continuous-time adaptive cable equalizer using enhanced low-frequency gain control method

This paper describes a high-speed CMOS adaptive cable equalizer using an enhanced low-frequency gain control method. The additional low-frequency gain control loop enables the use of an open-loop equalizing filter, which alleviates the speed bottleneck of the conventional adaptation method. In addition, combined adaptation of low-frequency gain and high-frequency boosting improves the adaptation accuracy while supporting high-frequency operation. The open-loop equalizing filter incorporates a merged-path topology and offers infinite input impedance, which are suitable for higher frequency operation and cascaded design. This equalizing filter controls its common-mode output voltage level in a feedforward manner, thereby improving bandwidth. A prototype chip was fabricated in 0.18-/spl mu/m four-metal mixed-mode CMOS technology. The realized active area is 0.48/spl times/0.73 mm/sup 2/. The prototype adaptive equalizer operates up to 3.5 Gb/s over a 15-m RG-58 coaxial cable with 1.8-V supply and dissipates 80 mW. Moreover, the equalizing filter in manual adjustment mode operates up to 5 Gb/s over a 15-m RG-58 coaxial cable.     

Zur Kinetik der verschleißinduzierten Wasserstoffeffusion aus unlegiertem Stahl

Unter Anwendung elektrochemischer und massenspektrometrischer Methoden wird in der vorliegenden Arbeit versucht, sowohl die einzelnen Beiträge zur verschleißinduzierten Wasserstoffeffusion quantitativ zu erfassen wie auch den Zusammenhang zwischen der verschleißgeförderten Wasserstoffeffusion und der Wasserstoffanreicherung in oberflächennahen Bereichen zu erforschen. Haftungsverschleiß- und Furchungsverschleiß-induzierte Wasserstoffeffusionsmechanismen sind meistens auf die mechanische Abtragung der wasserstoffangereicherten Schichten bzw. auf die Thermodiffusion aus diesen Schichten zurückzuführen. Nach einem Anlaufstadium stellt sich ein Gleichgewicht zwischen dem effundierenden und dem eingefangenen Wasserstoff ein. In diesem Stadium erfolgt die Wasserstoffeffusion mit stationärer Geschwindigkeit.