Using Generic Pheromone Lures to Expedite Identification of Aggregation Pheromones for the Cerambycid Beetles Xylotrechus nauticus, Phymatodes lecontei, and Neoclytus modestus modestus

Males of several species of longhorned beetles in the subfamily Cerambycinae produce sex or aggregation pheromones consisting of 2,3-hexanediols and/or hydroxyhexanones. We tested the hypothesis that this diol/hydroxyketone pheromone motif is highly conserved within the subfamily, and the resulting prediction that multiple cerambycine species will be attracted to compounds of this type. We also tested the concept that live traps baited with generic blends of these compounds could be used as a source of live insects from which pheromones could be collected and identified. Traps placed in a mature oak woodland and baited with generic blends of racemic 2-hydroxyhexan-3-one and 3-hydroxyhexan-2-one captured adults of both sexes of three cerambycine species: Xylotrechus nauticus (Mannerheim), Phymatodes lecontei Linsley, and Phymatodes decussatus decussatus (LeConte). Odors collected from male X. nauticus contained a 9:1 ratio of two male-specific compounds, (R)- and (S)-3-hydroxyhexan-2-one. Field trials with synthetic compounds determined that traps baited with (R)-3-hydroxyhexan-2-one (94% ee), alone or in blends with other isomers, attracted similar numbers of X. nauticus of both sexes, whereas (S)-3-hydroxyhexan-2-one (94% ee) attracted significantly fewer beetles. Phymatodes lecontei and P. d. decussatus also were caught in traps baited with hydroxyhexanones, as well as a few specimens of two other cerambycine species, Neoclytus modestus modestus Fall (both sexes) and Brothylus gemmulatus LeConte (only females). Male N. m. modestus produced (R)-3-hydroxyhexan-2-one, which was not present in extracts from females. Neoclytus m. modestus of both sexes also responded to lures that included (R)-3-hydroxyhexan-2-one as one of the components. The only male-specific compound found in extracts from P. lecontei was (R)-2-methylbutan-1-ol, and adults of both sexes were attracted to racemic 2-methylbutan-1-ol in field bioassays. Surprisingly, P. lecontei of both sexes also were attracted to (R)- and (S)-3-hydroxyhexan-2-ones, although neither compound was detected in extracts from this species. Males of all five beetle species had gland pores on their prothoraces that were similar in structure to those that have been associated with volatile pheromone production in other cerambycine species. The attraction of multiple cerambycine species of two tribes to (R)-3-hydroxyhexan-2-one in this study, and in earlier studies with other cerambycine species, suggests that this compound is a widespread aggregation pheromone component in this large and diverse subfamily. Overall, the attraction of multiple species from different cerambycine tribes to this compound at a single field site supports the hypothesis that the hydroxyketone pheromone structural motif is highly conserved within this subfamily.     

Dye sensitized CO<Subscript>2</Subscript> reduction over pure and platinized TiO<Subscript>2</Subscript>

TiO₂ thin and thick films promoted with platinum and organic sensitizers including novel perylene diimide dyes (PDI) were prepared and tested for carbon dioxide reduction with water under visible light. TiO₂ films were prepared by a dip coating sol–gel technique. Pt was incorporated on TiO₂ surface by wet impregnation [Pt(on).TiO₂], or in the TiO₂ film [Pt(in).TiO₂] by adding the precursor in the sol. When tris (2,2′-bipyridyl) ruthenium(II) chloride hexahydrate was used as sensitizer, in addition to visible light activity towards methane production, H₂ evolution was also observed. Perylene diimide derivatives used in this study have shown light harvesting capability similar to the tris (2,2′-bipyridyl) ruthenium(II) chloride hexahydrate.     

Transamination Reactivity of Ti(NMe2)4 and Zr(NMe2)4 with 1,3,4,5,6-Pentamethyl-2-aminoborazine and Aryl Amines. Model Chemistry for the Formation of Metalloborazine Preceramic Polymers and MN/BN (M?=?Ti, Zr) Ceramic Composites

The transamination reactions between Ti(NMe₂)₄ and 1,3,4,5,6-pentamethyl-2-aminoborazine, (Me)₃N₃(Me)₂B₃(NH₂), and diphenylamine (Ph₂NH) and between [Zr(NMe₂)₄]₂ and 1,3,4,5,6-pentamethyl-2-aminoborazine, aniline (PhNH₂) and diphenylamine have been studied and the molecular product species have been isolated, spectroscopically characterized and single crystal X-ray structure analyses completed. The results of these studies have been used to interpret the outcome of reactions of Ti(NMe₂)₄ and Zr(NMe₂)₄ with borazinylamine preceramic polymers that, upon pyrolysis, produce TiN/BN, ZrN/BN and ZrH_0.6N/BN composite powders. The transamination reactivity of a two-point poly(borazinylamine) oligomer having terminal –NH₂ amino groups with Ti(NMe₂)₄ and Zr(NMe₂)₄ has been used to obtain metallated preceramic oligomers that, upon pyrolysis, give TiN/BN and ZrN/ZrH_0.6N/BN nanocomposites. Model reactions of 1,3,4,5,6-pentamethyl-2-amino borazine, aniline and Ph₂NH₂ with Ti(NMe₂)₄ and Zr(NMe₂)₄ are also described as models for the formation of the metallated oligomers. Molecular structure determinations for the metal amides are presented. We dedicate this paper to Professor Christopher W. Allen in recognition of his distinguished career and his accomplishments in inorganic ring and polymer chemistry.     

Pd(111) versus Pd–Au(111) in carbon monoxide oxidation under elevated pressures

The oxidation of CO on Pd(111) and Pd₇₀Au₃₀(111) has been studied under pressures upto 100 Torr. Gold is found to decrease the surface activity by inhibiting oxygen dissociation. For a sufficient conversion time depending on the CO coverage and the surface identity, a dramatic boost of activity occurs. This is ascribed to a switch from CO-induced inhibition of O₂ adsorption to a regime determined by CO adsorption. The other kinetic features are explained by oxidation of palladium and adsorption-induced restructuring of the surfaces.     

尼龙及超细尼龙专用活性染料-ERIOFAST

Eriofast是亨斯迈纺织染化部专门为尼龙及超细尼龙染色而并发的专用活性染料.本文除了叙述Eriofast活性染料开发的背景外,还阐明了使用与其相匹配而专用的Eriofast Fix交链剂的优点,尤其突出的是在染色工艺中使用氯化钙可以在全消光的聚酰胺纤维上获得很深的色相.     

Interfacial reaction between cubic boron nitride and Ti during active brazing

Thermodynamic and reaction process analyses were performed to understand the joining characteristic during high temperature brazing between cubic boron nitride (CBN) grit and a silver-base filler alloy containing Ti as an active element. Experimental information on the microstructure of the brazed joint, the composition of the interface, and the shape of the compounds formed on the surface of the grit was obtained by scanning electron microscopy, energy-dispersive x-ray, and x-ray diffraction. The results indicate that Ti in the molten filler alloy facilitated good wetting between the solid CBN crystals and braze filler alloy. The transition layer formed by the interaction of TiN and TiB₂ was one of the key factors in joining the CBN and steel substrate.     

Exploring thermal spray gray alumina coating pore network architecture by combining stereological protocols and impedance electrochemical spectroscopy

Complex multiscale pore network architecture characterized by multimodal pore size distribution and connectivity develops during the manufacture of ceramic thermal spray coatings from intra- and interlamellar cracks generated when each lamella spreads and solidifies to globular pores resulting from lamella stacking defects. This network significantly affects the coating properties and their in-service behaviors. De Hoff stereological analysis permits quantification of the three-dimensional (3D) distribution of spheroids (i.e., pores) from the determination of their two-dimensional (2D) distribution estimated by image analysis when analyzing the coating structure from a polished plane. Electrochemical impedance spectroscopy electrochemically examines a material surface by frequency variable current and potential and analyzes the complex impedance. When a coating covers the material surface, the electrolyte percolates through the more or less connected pore network to locally passivate the substrate. The resistive and capacitive characteristics of the equivalent electrical circuit will depend upon the connected pore network architecture. Both protocols were implemented to quantify thermal spray coating structures. Al₂O₃-13TiO₂ coatings were atmospherically plasma sprayed using several sets of power parameters, are current intensity, plasma gas total flow rate, and plasma gas composition in order to determine their effects on pore network architecture. Particle characteristics upon impact, especially their related dimensionless numbers, such as Reynolds, Weber, and Sommerfeld criteria, were also determined. Analyses permitted identification of (a) the major effects of power parameters upon pore architecture and (b) the related formation mechanisms. This article was originally published inBuilding on 100 Years of Success, Proceedings of the 2006 International Thermal Spray Conference (Seattle, WA), May 15–18, 2006, B.R. Marple, M.M. Hyland, Y.-Ch. Lau, R.S. Lima, and J. Voyer, Ed., ASM International, Materials Park, OH, 2006.     

Enhancement of magnetic texture and functional characteristics of iron-based soft magnetic alloys

It has been shown that the formation of nitride-oxide magnetically active electrically insulating coatings on ribbons of iron-based soft magnetic alloys using the method of ion-plasma deposition and subsequent magnetic annealing in an ac magnetic field leads to a substantial improvement of their static and dynamic magnetic properties.     

Shock-wave compacting of a Fe-Ni-Al powder mixture and its study

The results are presented which concern measurements of X-ray diffraction spectra, microstructure, temperature dependences of the real part of the complex magnetic susceptibility, the elastic modulus, and internal friction of an Fe₆₅Ni₂₃Al₁₂ powder mixture obtained by shock-wave compacting. A series of anomalies of the magnetic and elastic properties have been found. It has been assumed that the observed features of magnetic and acoustic spectra of the composite can be caused by a number of factors, such as the formation of a metastable state, intermediate phases, and superstructures or by polymorphic transformations arising upon shockwave compacting at particle boundaries.     

Surface modification of rutile TiO2 by submerged arc discharge for improved photoreactivity

Titanium dioxide is well known for its photocatalytic activity, but it works effectively only in the ultraviolet (UV) range. Given the relatively low flux of solar UV that reaches earth, the potential of exploring its photocatalytic capacity for environmental protection applications is very limited. In this study, rutile, the least photocatalytic of the three existing titanium dioxide crystalline forms, was suspended in water or acetonitrile and treated with oxygen or argon plasmas, using a novel dense-medium plasma technology (submerged arc discharge). As a result of the plasma treatment, rutile particles were doped with various trace elements that originated in electrodes made of different metals. Subsequent analyses show that the photocatalytic capacity of plasma-modified rutile is comparable to or even better than that of unmodified anatase, the most photocatalytic form of titanium dioxides. The color change of TiO₂ samples after plasma treatment indicates that the modified rutile absorbs visible light and may therefore work as a photocatalyst in the visible range. Given the fact that rutile can be produced in large quantity more easily and cheaply than can anatase, these results are very encouraging and open up possibilities in using rutile for photocatalytic applications in the visible range. This paper was presented at the Third International Surface Engineering Congress and Exposition held August 2–4, 2004 in Orlando, FL.