ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

Hits per page

hits 1 - 2 | 2 hits

Sorting

Electronic Resource

Methyl salicylate and (−)-(1R,5S)-myrtenal are plant-derived repellents for black bean aphid,Aphis fabae Scop. (Homoptera: Aphididae) (1994)

Hardie, Jim ; Isaacs, Rufus ; Pickett, John A. ; [et al.]

Springer

Journal of chemical ecology 20 (1994), S. 2847-2855

add to mindlist on the mindlist

Details

ISSN: 1573-1561

Keywords: Aphid ; Aphis fabae ; Homoptera ; Aphididae ; semiochemicals ; chemical ecology ; electrophysiology ; salicylate ; monoterpenoid

Source: Springer Online Journal Archives 1860-2000

Topics: Biology , Chemistry and Pharmacology

Notes: Abstract Methyl salicylate and (−)-(1R,5S)-myrtenal stimulate specific olfactory cells in the primary rhinaria on the sixth and fifth antennal segments, respectively, of the black bean aphid.Aphis fabae. In behavioral studies employing a linear track olfactometer, both compounds were repellent toA. fabae and also inhibited attraction to volatiles from its host, broad bean (Vicia faba). Methyl salicylate is associated with secondary metabolite-based defense in plants, and the monoterpenoid (−)-(1R,5S)-myrtenal is metabolically related to (−)-(1S,5S)-α-pinene, an abundant component of defensive resins produced by gymnosperms. It is argued that these two compounds are employed byA. fabae as indicators of nutritionally unsuitable or nonhost plants.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF02098393

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Characterization of the oxidation of tantalum nitride (1993)

Ibidunni, A. O. ; Masaitis, R. L. ; Opila, R. L. ; [et al.]

Chichester [u.a.] : Wiley-Blackwell

Surface and Interface Analysis 20 (1993), S. 559-564

add to mindlist on the mindlist

Details

ISSN: 0142-2421

Keywords: Chemistry ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Physics

Notes: Sputter-deposited non-stoichiometric tantalum nitride films are used for laser-trimmed thin-film resistors owing to their stability and processability. The films are stabilized by heating in air to form a passive Ta2O5 film. This passive film can be destroyed if the resistors are exposed to aggressive thermal or chemical conditions. Thus we have studied sputtered TaN films and resistors deposited on SiO2 and Al2O3 substrates and exposed to either KOH solutions or air at 250-500 °C for various times. The oxidized films have been characterized with Auger electron spectroscopy (AES), x-ray photelectron spectroscopy (XPS), x-ray absorption near-edge spectroscopy (XANES) and extended x-ray absorption fine structure (EXAFS). Chemical shifts in the NOO Auger spectrum have been used to show that the initial fraction of deposited TaN reacts with the SiO2 surface to form Ta2O5. X-ray photoelectron spectroscopy showed that although significant amounts of oxygen can be present in the sputered films, little of the tantalum is fully oxidized to Ta2O5. X-ray photoelectron spectroscopy was also used to show that the oxide layer slowly increases in thickness when heated in air. Finally, KTaO3 was identified by XANES on the surface of films exposed to KOH. Once the passive Ta2O5 is converted to KTaO3, further oxidation of the underlying films occurs. The mechanism of oxidation of these films and the unique advantages of each spectroscopic technique are discussed.

Additional Material: 6 Ill.