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Highly oxygenated guaianolides from Anthemis cretica subsp. cretica
(Elsevier, 1999)
Two new guaianolides, i.e. anthemolide B and 8-O-angeloyl-9-O- acetylanthemolide B, in addition to 12 known closely related guaianolides were identified in the aerial parts of the flowering plant Anthemis cretica subsp. cretica.
Silicon UV flame detector utilizing photonic crystal
(Society of Photo-Optical Instrumentation Engineers, 1999)
Abstract
In this paper we propose a silicon UV flame detector for combustion systems. In gas burners the relative intensity of flame radiation is dominant in the ultraviolet region (below 0.35 μm). In the visible and ...
Enhancement of radiative lifetime in semiconductors using photonic crystals
(Elsevier, 1999)
Abstract
In this work we present a structure consisting of a semiconductor sample immersed between two one-dimensional photonic crystals, designed with the aim to investigate the possibility to increase radiative lifetime ...
The influence of solidification rate on the microstructure and distribution of solute during the solidification of Al-Cu alloy / Uticaj brzine očvršćavanja na mikrostrukturu i raspodelu primesa tokom očvršćavanja legure Al-Cu
(Savez inženjera metalurgije Jugoslavije, 1999)
In this paper investigation of the influence of solidification rate on the microstructure and distribution of solute during the solidification of Al-2.2%Cu by Vertical Bridgman method was performed. The experiments were ...
Electrochemical activation of the electroless deposition of Ni–P alloy and phase structure characterization of the deposit. Part I: Dual bath system
(Springer, 1999)
A typical low temperature alkaline bath was chosen for the investigation of the effect of electrochemical activation on the efficiency of the electroless deposition of Ni and on the phase structure of the Ni–P alloys ...
Stereoselective transformation of cyclodecene-1,4-dione systems, derived from steroids, to the corresponding spiro-g-lactones. A semiempirical MO Study
(MDPI, 1999)
The thermal and acid-catalyzed intramolecular rearrangement of the (Z)- and (E)-cyclodecene-1,4-dione compounds deriving from steroids, 2a,b and 3a,b, respectively, proceeds stereoselectively to give the corresponding ...
The Characterization of Sintered SmCo5 Magnets
(Association for ETRAN Society, 1999)
During the investigation and design of laboratory model of a Sintered SmCo5 magnet, a group of methods for characterizing sintered and heat treated magnets was defined. The direct dependence of the magnetic properties of ...
Electrochemical Deposition and Phase Structure of Electrodeposited Ni-W Alloys / Elektrohemijsko taloženje i fazna struktura legura Ni-W
(Serbian Chemical Society, 1999)
The induced deposition of W in the presence of iron-group metals has been known for a long time without a proper understanding of the mechanism of codeposition. Hints were made by several authors, concerning primarily a ...
13,14-Seco-steroids: A New Type of Modified Steroids Containing a Nine-Membered Ring
(Wiley, 1999)
Oxidations of 14α‐hydroxy‐5α‐cholestan‐3β‐yl acetate (5) with lead tetraacetate under thermal or photolytic conditions or in the presence of iodine proceed mainly by fragmentation of the C(13)−C(14) bond to give as the ...
Guaianolides from Centaurea nicolai: Antifungal activity
(Elsevier, 1999)
A new guaianolide, 3-deacetyl-9-O-acetylsalograviolide A, along with four known closely related lactones, salograviolide A, 9-O- acetylsalograviolide A, kandavanolide and salograviolide B were detected in the aerial parts ...