Identification of chemical oviposition stimulants from rice grain forSitophilus zeamais motschulsky (Coleoptera,Curculionidae)

Chemical components stimulating oviposition bySitophilus zeamais in rice grain were isolated from rice bran and were found to be a mixture of ferulates, diglycerides, and free sterols. Oviposition preference of the species can be induced by synergistic action of these compounds.     

Chemical and Chromatic Bases for Preferential Visiting By the Cabbage Butterfly, Pieris rapae, to Rape Flowers

Scent and coloration of corolla were examined as floral attributes responsible for preferential visiting by the cabbage butterfly, Pieris rapae, to rape flower, Brassica rapa. Floral volatile components that release the flower-visiting behavior of the butterfly were identified by chemical analyses, electroantennography (EAG), and two behavioral bioassays: proboscis extension reflex (PER) in response to odor and attraction to artificial flowers. GC and GC-MS analyses of the headspace volatiles from the flowers revealed the presence of six aromatic compounds, benzaldehyde, phenylacetaldehyde, benzyl alcohol, 2-phenylethanol, phenylacetonitrile, and indole in decreasing order of quantity. Of these, phenylacetaldehyde elicited the highest response in the PER assay. While benzyl alcohol, 2-phenylethanol, benzaldehyde, and phenylacetonitrile evoked moderate responses, the PER-eliciting activity of indole was very weak. In two-choice behavioral bioassays, artificial flowers scented with any one of these PER-active compounds attracted significantly more butterflies than control (unscented) flowers, whereas those treated with indole were almost inactive. The EAG activities of the six chemicals were not high and were about the same at a low dose (1 g), but phenylacetaldehyde elicited a much stronger response from both sexes at higher doses (10 and 100 g). An overall profile of EAG responses at a dose of 100 g was analogous to that of PER performance, suggesting that floral volatiles may be involved in close-range location or recognition of flowers rather than long-range attraction. By spectroscopic and UV-photographic examinations of rape flower, the central part of the corolla was found to absorb UV rays in marked contrast to the other parts, which reflected near-UV rays (_max = 350 nm). This indicates that the flower is endowed with a conspicuous nectar guide that is probably an important visual stimulus for attracting foraging adults of P. rapae. Consequently, the present findings strongly suggest that this elaborate pollination strategy of rape flower, characterized by its good combination of olfactory and visual attractiveness, accounts for preferential visiting by the cabbage butterfly to the flower.     

Design and fabrication of a length-extensional mode rectangular X-cut quartz resonator with zero temperature coefficient.

Rectangular X-cut quartz crystal resonators with cut angles theta > 5.0 degrees and aspect ratios Rzy (= width 2z0/length 2y0) from 0.3 to 0.5 are investigated. The resonators oscillate mode is a length-extensional mode. A semiempirical frequency equation was derived from the stress expressed in terms of the trigonometric and the hyperbolic transcendental functions with constants estimated by the regression curve fit to the stress simulated by the finite-element method (FEM). Contours on which a point satisfies a zero first order temperature coefficient condition are shown in a cut angle theta and Rzy diagram. We proved that a fabricated resonator with Rzy = 0.400 and theta = 16.0 degrees, whose design parameter is located in the area of the contour, had a zero temperature coefficient.     

The pumping performances of the turbomoleculae pump simulated by direct simulation monte carlo method

Turbomolecular pumps (TMPs) are used extensively in several highly important areas of industry and research. The performances of TMP are evaluated by maximum throughput and maximum pressure ratio. In this paper, they are investigated by DSMC method. A 3D analysis in a rotating reference frame is proposed to simulate this flow field. Considering the Coriolis and centrifugal accelerations, the equations about the molecular velocities and position are deduced. The VSS model and NTC collision schemes are used to calculate the intermolecular collisions. The diffuse reflection is employed on the molecular reflection from the surfaces of boundary. The procedures for establishment of the correct collision rate are based on the cells, while individual collision pairs are chosen from the sub-cells. The pump performances of one stage TMP under the different kinds of gas, different heights, and different blade angles are simulated and the results are analyzed. Numerical results agree well with the existing experiment data.     

Reduction of defects and improvement in the performance of blue phosphor for thick‐dielectric electroluminescent displays using Color‐by‐Blue

Abstract— Defect‐free large‐area inorganic thick‐dielectric EL (TDEL) displays using Color by Blue (CBB) technology have been successfully developed. We have achieved the world's highest blue‐phosphor luminance of 900 cd/m² for a single‐pixel device by using CBB and by optimizing the e‐beam gun configuration and the flow rate of H₂S in the vacuum chamber. By analyzing the defects on panels with triple‐pattern phosphors and CBB panels, we also found that the number of defects on CBB panels can be drastically reduced compared with those on triple‐pattern panels. The defect‐free 17‐in. VGA CBB panels show better characteristics, a high peak luminance of 600 cd/m² and a high contrast ratio of 1000:1, compared with those of triple‐pattern panels.     

Sieving of aerosol particles with metal screens

Metal screens with uniform micrometer-sized opening were employed to sieve aerosol particles by suppressing the adhesion of particles smaller than the openings. The collection efficiencies of monodispersed polystyrene latex (PSL) particles were experimentally determined using the metal screens with 1.2, 1.8, 2.5, and 4.2 μm openings at various filtration velocities. The particles smaller than the mesh opening adhered on the metal screen at a low filtration velocity, but the bounce-off of particles on the mesh surface suppressed the adhesion at a high velocity. As a result, we found that the adhesion of PSL particles larger than 0.3 μm mostly suppressed at a filtration velocity higher than 10 m s^?1 and therefore we can sieve aerosol particles according to the opening size of metal screens. We also found that the particle number concentration could be determined by measuring the increase in pressure drop since the clogging of metal screen openings takes place by the individual particles.

© 2016 American Association for Aerosol Research     

Synthesis of Hard Materials by Field Activation: The Synthesis of Solid Solutions and Composites in the TiB2–WB2–CrB2 System

The synthesis of solid solutions of (Ti,W,Cr)B₂ from elemental reactants using the field-activated, pressure-assisted synthesis method and employing the SPS apparatus was investigated. The nature of the products depended on temperature; they were nearly pure solid solutions at 1900°C with minor amounts of β-WB. The product density and microhardness depended on the temperature of synthesis for the same value of applied pressure (64 MPa). Samples with the highest density (94%) corresponded to a hardness of 22.7 GPa. When annealed at 1500°C, the solid solutions decomposed, precipitating a (W,Ti,Cr)B₂ phase in a spinodal form. In addition, β-WB precipitates in the form of thin (0.4–5.3 nm) layers were observed. They existed in a 60°/120° orientation to the (Ti,W,Cr)B₂ matrix, in agreement with previous observations. Highly faceted, small (nanosized) pores associated with the β-WB precipitates were also observed.