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Sesquiterpene lactones from Achillea crithmifolia
(Elsevier, 1991)
The isolation of guaianolides rupicolin-A, rupicolin-B, their acetates and a new germacranolide 1β,10α-epoxy-3β,9β-diacetoxy-11α,13-dihydrocostunolide, identified by means of PS DQF COSY and PS NOESY, from Achillea ...
Identification of intermetallic compounds in thin layers of electrodeposited Cu–Cd alloys using electrochemical techniques
(USA :Taylor & Francis INC, 1991)
An attempt was made to analyse the phase structure of thin layers of electrodeposited Cu–Cd alloys using anodic linear sweep voltammetry combined with a potentiostatic pulse technique (ALSV–PPT). The results were compared ...
Sesquiterpene lactones from Achillea crithmifolia
(American Chemical Society, 1994)
The isolation of three highly oxygenated guaianolides, desacetyl-1α-4α- dihydroxybishopsolicepolide [1], its 4β-hydroxy epimer 2 (a new compound), and 1β,2β:3β,4β-diepoxy-8α,10α-dihydroxyguai-12(13)-en-12,6α-olide [3], ...
Photodiode quantum efficiency optimization using spherical pits on active surfaces
(Elsevier, 1995)
A numerical model of a photodiode with etched spherical pits on an active surface has been developed. Several geometrical parameters (radius of curvature, depth and arrangement of spherical pits, sample thickness and area, ...
Regioselectivity in Cyclofunctionalization of Olefinic Alcohols with Benzeneselenenyl Halides at Different Temperatures
(Wiley, 1992)
The regioselectivity in cyclofunctionalization of some acyclic olefinic alcohols with benzeneselenenyl halides (PhSeCl and PhSeBr) at different temperatures (−78°C, 0°C and room temperature) is investigated. It has been ...
Pulse deposition of Au on graphite
(Elsevier, 1996)
In this paper we present pulse deposition as a new method to favor the self-assembly of nanostructured materials. Nucleation and growth of gold thin layers deposited on highly oriented pyrolytic graphite substrate have ...
Single-particle settling velocity through liquid fluidized beds
(Elsevier, 1991)
Single-particle settling velocities through waterfluidized
beds have been studied experimentally using
a standard fluidtzation column 40 mm in diameter.
All the particles used were spherical. The combinations
of ...
Hydrogen adsorption on single-crystal platinum electrodes in alkaline solutions
(Elsevier, 1992)
Hydrogen adsorption on single-crystal platinum low-index and stepped surfaces was studied in 0.1 M and 0.01 M NaOH solutions. A strong dependence on the crystallographic orientation of the electrode surface was found. The ...
Properties of activated alumina obtained by flash calcination of gibbsite
(Elsevier, 1992)
On exposing gibbsite, with granulation below 10 μm to flash calcination of 0.5 s in the regime of pneumatic transport and at temperatures above 883 K, a microcrystalline material with a high degree of amorphization was ...
Surface morphology and the response of piezoelectric gas sensors
(Elsevier, 1995)
The surface morphology of gold electrodes on piezoelectric quartz crystals was characterized by scanning electron microscopy and scanning tunnelling microscopy. Sensors with various coating materials as polymers, liquid ...