Input-output linearization of retarded non-linear systems by using an extension of Lie derivative

This paper considers the input-output linearization problem for retarded non-linear systems, which have time-delays in the state. By using an extension of the Lie derivative for functional differential equations, we derive a coordinates transformation and a static state feedback to obtain linear input-output behaviour for a class of retarded non-linear systems. The obtained coordinates transformation is allowed to contain not only the current value of the state variables but also the past values of ones. In addition, we show that the coordinates transformation is invertible in a neighbourhood of the origin and examine the stability condition of the closed loop system with the static state feedback. The effectiveness of the proposed technique is demonstrated through numerical simulations.     

Lithium silicon sulfide as an anode material in all-solid-state lithium batteries

The electrochemical properties of Li₂SiS₃ were investigated in a solid electrolyte. Li₂SiS₃ was converted to elemental Si, and the resultant Si was formed into Si-Li alloy in the reduction process; however, the reverse reaction was not completed due to the loss of electronic conduction upon reoxidation. FeS was dispersed as a conductive additive in Li₂SiS₃ films by pulsed laser deposition (PLD). The addition allowed successive reactions to proceed at a large capacity with small capacity-fading during the cycling process in spite of the small FeS fraction. This result indicates that Li₂SiS₃ + FeS thin film is a promising anode for solid-state lithium batteries.     

Recent advances in phosphorylation of food proteins: A review

Phosphorylation is a useful method for improving the functional properties of food proteins. In this article, various methods of phosphorylation are reviewed. Dry-heating phosphorylation, a method developed recently, is also introduced. Some characteristics of phosphate groups are involved, and the effects of phosphorylation on the structural changes, the functional properties, and the physiological functions in vitro of food proteins, are discussed. The types of phosphate linkages and the phosphopeptides from phosphorylated proteins are identified. The molten (partially unfolded) conformations of food proteins formed by phosphorylation are discussed. The phosphorylation of food proteins improved a number of functional properties, including heat stability, emulsifying properties, foaming properties, gelling properties, water absorption capacity, oil absorption capacity, and calcium phosphate-solubilizing ability. In vitro physiological function studies of protein (α-lactoalbumin) indicated that the digestibility (ovalbumin) was improved and the inflammatory response (α-lactoalbumin) was suppressed by phosphorylation. Experiments with animals are necessary to evaluate the toxicity and physiological functions of phosphorylated proteins.     

ACCELERATION OF CRACK GROWTH UNDER INTERMITTENT OVERSTRESSING IN DIFFERENT ENVIRONMENTS

Fatigue crack growth behaviour under intermittent overstressing was investigated in moist air, dry air, nitrogen and vacuum with low carbon steels under tension-compression loading with a few tests under compression-tension loading. A very small number of cycles of overstress applied intermittently during a very large number of cycles of understress below threshold caused significant acceleration, of about one hundred times, in crack growth rate as compared to the case of steady cyclic stress in the cases of moist air, dry air and nitrogen. In the region of low understress, the acceleration in moist air was appreciably less than that in dry air and nitrogen due to oxide-induced crack closure. The acceleration in vacuum was smaller than that in other environments over all understress levels, possibly because of rewelding. There was no effect of an overstress sequence on the acceleration.     

Development of confocal laser microscope system for examination of microscopic characteristics of radiophotoluminescence glass dosemeters

A confocal laser microscope system was developed for the measurement of radiophotoluminescence (RPL) photons emitted from a minute alpha-ray-irradiated area in an RPL glass dosemeter. The system was composed mainly of an inverted-type microscope, an ultraviolet laser, an XY movable stage and photon-counting circuits. The photon-counting circuits were effective in the reduction of the background noise level in the measurement of RPL photons. The performance of this microscope system was examined by the observation of standard RPL glass samples irradiated using (241)Am alpha rays. The spatial resolution of this system was ～ 3 μm, and with regard to the sensitivity of this system, a hit of more than four to five alpha rays in unit area produced enough amount of RPL photons to construct the image.     

High‐Yield Preparation,Versatile Structural Modification,and Properties of Layered Cobalt Hydroxide Nanocones

A low‐cost oil bath synthetic route is presented to produce uniform and highly crystalline layered cobalt hydroxide nanocones (NCs) intercalated with dodecyl sulfate anions (C₁₂H₂₅OSO₃^?, DS^?). A new exfoliating procedure, by gradually unravelling/unzipping these NCs through heat treatment in formamide‐water binary solution, is developed to prepare unilamellar nanosheets. Moreover, the NCs can be readily modified with various inorganic or organic anions via a conventional anion‐exchange process at ambient temperature. The exchanged product, for example, NO₃^?–intercalated NCs, can be more easily and rapidly transformed into cobalt oxides (e.g., Co₃O₄ and CoO) than the original DS^?–intercalated form while retaining a conical feature. Both the cobalt hydroxide NCs and exfoliated nanosheets are electrochemically redoxable, exhibiting a Faradaic pseudocapacitive behavior. The magnetic measurements further reveal both antiferromagnetic behaviors for transformed Co₃O₄ and CoO NCs. Their Néel temperature values are lower than those of bulk oxides due to finite size and geometric confinement effect. The peculiar conical feature of NCs with a hollow interior and tunable layer spacing, as well as exfoliated unilamellar nanosheets with all surface area exposed, may show promise for potential applications in electrochemical energy storage and magnetic devices.     

Effect of cross-flow on the frequency of bubble formation from a single-hole nozzle

Bubble formation from a single-hole nozzle placed vertically upward in a rotating water bath was investigated using a high-speed video camera. Air was used as the working gas. The measured values of the frequency of bubble formation, f _B, were compared with those observed in a stationary bath, f _B0. The velocity of cross-flow, ν_θ, affected the bubble formation significantly when it exceeded a critical value, ν_θc . The ratio of f _B to f _B0 was unity for ν_θ≦ν_θc , but it changed in a complex manner for ν_θ>ν_θc . In the latter case, when the air flow rate Q _g was relatively low, f _B/f _B0 became larger than unity irrespective of Q _g, and an empirical correlation of f _B/f _B0 was proposed as a function of ν_θ and the inner diameter of the nozzle, d _ni. As the gas flow rate increased, f _B/f _B0 decreased monotonically and became smaller than unity, and an empirical correlation of f _B/f _B0 was derived as a function of Q _g, ν_θ, and d _ni. These empirical correlations could approximate the measured values of f _B/f _B0 within a scatter of −15 to +20 pct.