Search results for "BESS"
showing 10 items of 144 documents
Zvaigžņotā Debess: 2005, Rudens
2005
Latvijas Zinātnes padome, Latvijas Universitāte
Karyological observations on plant taxa endemic to the Balearic Islands
2007
Mitotic chromosome numbers are reported from 35 vascular plant taxa endemic to the Balearic Islands that are poorly known cytogenetically. The chromosome numbers of Chaenorhinum rodriguezii (2n = 14), Coristospermum huteri (2n = 22), Carduus ibicensis (2n = 26), Filago petro-ianii (2n = 26), Ononis crispa ssp. zschackei (2n = 30), and Ophrys bertolonii ssp. balearica (2n = 36) were determined for the first time. New chromosome numbers are reported in Pimpinella bicknellii (2n = 22), Calamintha rouyana (2n = 46), Vicia bifoliolata (2n = 14), and Teucrium asiaticum (2n = 30). A new diploid cytotype (2n = 16) was found in Ranunculus paludosus ssp. barceloi, which is restricted to populations f…
Zvaigžņotā Debess: 2014/15, Ziema (226)
2014
Contents: “ZVAIGŽŅOTĀ DEBESS” FORTY YEARS AGO: J.Stradiņš. Vestige of Otto Schmidt in Latvia (abridged) ; Leonora Roze. All-Union Conference in Latvian State University (abridged) ; DEVELOPMENTS in SCIENCE: K.Schwartz. Gravitational Waves and Cosmic Inflation ; DISCOVERIES: A.Alksnis. Light Echoes from Supernova 2014J in Galaxy M82 ; A.Alksnis. Discovery of the Benešov Meteorites 20 Years after the Bolide Event ; I.Pundure. Giant Filament on the Sun Watched by NASA's SDO ; I.Pundure. MAVEN’s Mars Exploration Mission Started ; SPACE RESEARCH and EXPLORATION: R.Misa. Plasma Engines and Ad Astra Rocket Company ; LATVIAN SCIENTISTS: J.Freimanis. Reviewing My 60 Years of Life (concluded) ; KĀRLI…
Volatile components from aerial parts of Centaurea gracilenta and C. ovina ssp. besserana growing wild in Bulgaria
2011
The essential oils of Centaurea gracilenta Velen. (CG) and C. ovina Pall. ex Willd. ssp. besserana (DC.) Dostál (COB) growing wild in Bulgaria, were studied by GC and GC-MS. Forty-five compounds for CG, representing the 90.1% of the oil, and 68 compounds for COB, representing the 91.9% of the oil, were identified. The oils were rich in sesquiterpenoids (33.4% for CG and 27.3% for COB), hydrocarbons (28.3% for CG and 10.7% for COB) and carbonylic compounds (12.7% for CG and 13.1% for COB). Fatty acids were abundant only for COB (31.3%). beta-Eudesmol (12.8%), nonacosane (11.8%) and p-vinyl guiacol (7.5%) were recognized as the main constituents for CG, while hexadecanoic acid (21.4%), spathu…
Zvaigžņotā debess: 2020, Pavasaris (247)
2020
Zvaigžņotā Debess: 2009, Vasara (204)
2009
Contents: E.Conners. The Trojan Asteroids ; V.Šmēlings. Men on the Moon! ; E.Bervalds. Astronomical Domes and “Sauna” ; Z.Alksne, A.Alksnis. Sakurai’s Object Fails to Escape Own Dust ; Z.Alksne, A.Alksnis. R CrB Stars Surrounded by Dust Clouds ; M.Gills. April Started with Astronomy ; A.Alksnis. First Stamps Dedicated to Astronomy by Latvia’s Post-Office ; I.Pundure. Arturs Balklavs and Astronomy of Latvia (till 1969) ; M.Sudārs. Satellite Collisions – What Threat Do They Pose? ; I.Vilks. Dwarf Planets Names in Latvian ; Announcement on the 2nd International Symposium on Dark-sky Parks: 14-19 September 2009, Slovenia ; A.Andžāns. The Best Way to Fight Darkness Is to Switch on Light (Intervi…
Zvaigžņotā Debess: 2008, Vasara
2008
Latvijas Zinātņu akadēmija, Latvijas Universitāte
Zvaigžņotā Debess: 2004, Rudens (185)
2004
Contents: L.Kondraševa and I.Zimina. New Riga Planetarium ; I.Rabinovičs. Remembering Fricis Blumbahs ; N.Cimahoviča. 50 cm Reflector Constructed in Riga ; J.Tambergs. Problems of Dialogue between Quantum Mechanics and Theology. A.Alksnis, Z.Alksne. The Sloan Great Wall ; A.Balklavs. Radio Galaxy – Emitter of Very High Energy Gamma-Rays ; A.Balklavs. Cosmic Objects in Photos – 2 ; A.Balklavs. New Assessments of Fine-Structure Constant Variability ; N.Cimahoviča. Dark Electric Matter Objects Around Us ; A.Balklavs. New Data on the Solar Granulation ; J.Jaunbergs. The Sinking Cliffs on Io ; D.Krieviņš. Space Launchers of Early XXI Century ; M.Sudārs. SpaceShipOne Closest to X-Prize ; J.Harja.…
Zvaigžņotā Debess: 2007, Rudens
2007
Latvijas Zinātnes padome, Latvijas Universitāte
High speed cleaving of crystals with ultrafast Bessel beams
2017
International audience; We develop a novel concept for ultra-high speed cleaving of crystalline materials with femtosecond lasers. Using Bessel beams in single shot, fracture planes can be induced nearly all along the Bessel zone in sapphire. For the first time, we show that only for a pulse duration below 650 fs, a single fracture can be induced in sapphire, while above this duration, cracks appear in all crystallographic orientations. We determine the influential parameters which are polarization direction, crystallographic axes and scanning direction. This is applied to cleave sapphire with a spacing as high as 25 μm between laser impacts.