Photothermal Oxidation of Cinnamyl Alcohol with Hydrogen Peroxide Catalyzed by Gold Nanoparticle/Antimony-Doped Tin Oxide Nanocrystals

Gold nanoparticles with different mean sizes were formed on antimony-doped tin oxide nanocrystals by the temperature-varied deposition-precipitation method (Au/ATO NCs). Au/ATO NCs possess strong absorption in the near-infrared region due to Drude excitation in addition to the localized surface plasmon resonance (LSPR) of AuNPs around 530 nm. Au/ATO NCs show thermally activated catalytic activity for the oxidation of cinnamyl alcohol to cinnamaldehyde by hydrogen peroxide. The catalytic activity increases with a decrease in the mean Au particle size (d_Au) at 5.3 nm≤d_Au≤8.2 nm. Light irradiation (λ_ex >660 nm, ∼0.5 sun) of Au/ATO NCs increases the rate of reaction by more than twice with ∼95 % selectivity. Kinetic analyses indicated that the striking enhancement of the reaction stems from the rise in the temperature near the catalyst surface of ∼30 K due to the photothermal effect of the ATO NCs.     

Depth estimation of protoporphyrin IX objects in turbid media considering the fluorescence intensity ratio between two wavelengths of light for application in invasion diagnosis of gastric cancer

Optical Review - This paper demonstrates a method to estimate the depth of a fluorescence object in turbid media using dual-wavelength excited photodynamic diagnosis, to aid in the invasion depth...     

Manuals in orthogonal categories

The notion of a manual, introduced and investigated in detail by Foulis, Randall, and their followers, has turned out to be further reaching than its originators had envisaged. Its omnipresence is comparable with the notion of a sheaf, whose significance is well recognized by every pure and applied mathematician. The principal concern of this paper is to give an appropriate vehicle, as general as possible, by which the theory of manuals can be developed. The vehicle is called an orthogonal category, which is akin to the notion of a category with coproducts. Orthogonal categories provide also a new perspective on the notion of a sheaf over a complete Boolean algebra, deepening our comprehension of Boolean mathematics and paving the way to quantum mathematics.     

Electromagnetic shielding of HF lamps using wire structures:simulation and measurement

High-frequency (HF) operated lamps, such as HF fluorescent lamps, have several advantages over conventional ones but they contaminate the environment with their EM field emissions. The shielding of the electromagnetic emission should be realized without much effect on the emission of the light. Enclosing the lamps in a housing made of widely spaced thin wires could be an appropriate way to shield the electromagnetic field. The paper studies the effectiveness of some wire structures for shielding the electromagnetic emission from HF fluorescent lamps. An analytical study, method of moments (MoM), and measurements have been carried out to evaluate the strength of the near-field and the shielding effectiveness of the structures     

Stage-specific and age-dependent profiles of zinc, copper, manganese, and selenium in rat seminiferous tubules

Stage-specific and age-dependent profiles of zinc, copper, manganese, and selenium in testis were examined in Wistar rats by both inductively coupled argon plasma-mass spectrometry (ICP-MS) with a microdissection technique and in situ elemental imaging of micro-PIXE analysis. The young adult animals (10 weeks old) contained higher levels of zinc and manganese in the seminiferous tubules at stages VII-VIII than stages XI through VI and IX-X and the levels were higher than those of the immature and old animals. Copper and selenium levels at stages VII-VIII of the young adult animals were also higher than those of the immature and old animals. In stages VII and VIII, zinc was higher in the central area of the seminiferous epithelium, where spermatozoa were localized, demonstrating a cell-specific property. This revised version was published online in August 2006 with corrections to the Cover Date.     

Bias-stress-induced increase in parasitic resistance of InP-based InAlAs/InGaAs HEMTs

The reliability of InP-based HEMTs is studied, focussing on how it is affected by the doped layer material and gate recess structure. Bias-and-temperature stress tests reveal that fluorine-induced donor passivation in the recess region, formed adjacent to the gate electrode, causes the source resistance (R_s) to increase at large drain bias voltages. The increase in R_s can be prevented by using InP or InAlP as the carrier supply layer material instead of InAlAs. On the other hand, the increase in the drain resistance (R_d) does not depend on the material of the carrier supply layer, which suggests that a mechanism different from that in the case of R_s should be considered. It is also found that a deep gate recess suppresses the increase in R_d after long-term stressing.     

Electrotunable Non‐reciprocal Laser Emission from a Liquid‐Crystal Photonic Device

A liquid crystal (LC) photonic device with an anisotropic optical heterojunction structure has been fabricated. The device has a phase‐retarding nematic LC (NLC) layer sandwiched between two polymer cholesteric LC films with right‐handed helices of different pitches. Electrotunable non‐reciprocal light transmittance and unidirectional circularly polarized (CP) lasing emission have been successfully demonstrated for this device structure. Two left CP (LCP) lasing emission peaks are observed at the edges of the overlapping region between the two photonic bands in the structure and are shifted upon the application of a voltage. In contrast, a non‐reciprocal right CP (RCP) lasing emission peak emerges at one of the band edges and diminishes upon the application of a voltage. These phenomena are interpreted based on the selective reflection of RCP light and the reorientation of the NLC molecules by the application of a voltage.     

New field measurement system for single-mode fibre dispersion utilising wavelength division multiplexing technique

A new system designed to measure the chromatic dispersion of installed single-mode fibres is presented. This system utilises the modulation phase technique but eliminates the reference laser and fibre. A large dynamic range was demonstrated by the measurement of an 81.1 km length of fibre.