Search results for "RH"
showing 10 items of 15584 documents
CCDC 651165: Experimental Crystal Structure Determination
2008
Related Article: J.Martinez-Lillo, D.Armentano, G.De Munno, F.Lloret, M.Julve, J.Faus|2008|Dalton Trans.||40|doi:10.1039/b714563b
Vēsturiskās pilsētas ainavas pieeja kultūras mantojuma saglabāšanai Kuldīgā
2015
Kuldīgas vēsturiskajā centrā kultūras mantojums sastopams visplašākajā tā izpratnē. Jau desmit gadu pašvaldība praktizē plānveidīgas kultūras mantojuma pārvaldības aktivitātes, kas pamanītas un atzinīgi novērtētas ne tikai Latvijā, bet arī starptautiski. Tomēr pilsētvide ir dzīva un mainīga, demonstrējot spēju tapt pielāgotai sabiedrības vajadzībām un kalpot tai. Arī kultūras mantojuma aizsardzībai un saglabāšanai tādai vajadzētu būt – visaptverošai, ar ilgtspējīgu vēsturiskās pilsētvides pārvaldību un integrētai vispārējā pilsētas attīstības ietvarā. Šī pētījuma mērķis ir izstrādāt priekšlikumus Kuldīgas kultūras mantojuma pārvaldības pilnveidošanai, balstoties teorētiskajās atziņās par vē…
Servisu orientētas arhitektūras veiktspēja
2017
Mūsdienās, veidojot informācijas sistēmas, nepieciešams tās veidot elastīgas un daudzfunkcionālas, lai varētu nodrošināt klientu vēlmes un spēt sekot līdzi strauji mainīgajai pasaulei. Lai to nodrošinātu, informācijas sistēmas bieži tiek veidotas balstoties uz Servisu orientētu arhitektūru, kurā sistēmas funkcionālā daļa tiek veidota atsevišķi un smalki sadalīta. Darbā apskatītas servisu orientētas arhitektūras, to realizācija un pielietojumi, veiktspējas problēmas, un risinājumi, kā tās samazināt. Izmantojot iegūto informāciju, veikts šo risinājumu salīdzinājums, kurš izmantots lēmumu koka izveidē. Balstoties uz iegūto lēmumu koku, izvēlēts viens no risinājumiem, kas izmantots informācijas…
Hexakis(diethylacetamide)iron(II) hexahalorhenate(IV) ionic salts: X-ray structures and magnetic properties
2015
Two novel Fe<sup>II</sup>-Re<sup>IV</sup> compounds of general formula [Fe<sup>II</sup>(DEA)<inf>6</inf>][Re<sup>IV</sup>X<inf>6</inf>] where DEA = diethylacetamide and X = Cl (1) and Br (2) have been prepared and magnetostructurally characterised. Complexes 1 and 2 are isomorphic ionic salts that crystallise in the trigonal crystal system with space group R(-3). The rhenium(IV) ion in 1 and 2 is six-coordinate with six chloro (1) or bromo (2) ligands building a regular octahedral chromophore. The Fe<sup>II</sup> ion is also six-coordinate, and bonded to six oxygen atoms from six DEA molecules. [Fe<sup>…
Energy transfer in LH2 of Rhodospirillum Molischianum, studied by subpicosecond spectroscopy and configuration interaction exciton calculations.
2001
Two color transient absorption measurements were performed on a LH2 complex from Rhodospirillum molischianum by using several excitation wavelengths (790, 800, 810, and 830 nm) and probing in the spectral region from 790 to 870 nm at room temperature. The observed energy transfer time of ∼1.0 ps from B800 to B850 at room temperature is longer than the corresponding rates in Rhodopseudomonas acidophila and Rhodobacter sphaeroides. We observed variations (0.9-1.2 ps) of B800-850 energy transfer times at different B800 excitation wavelengths, the fastest time (0.9 ps) was obtained with 800 nm excitation. At 830 nm excitation the energy transfer to the B850 ring takes place within 0.5 ps. The m…
Genome architecture enables local adaptation of Atlantic cod despite high connectivity
2017
Adaptation to local conditions is a fundamental process in evolution; however, mechanisms maintaining local adaptation despite high gene flow are still poorly understood. Marine ecosystems provide a wide array of diverse habitats that frequently promote ecological adaptation even in species characterized by strong levels of gene flow. As one example, populations of the marine fish Atlantic cod (Gadus morhua) are highly connected due to immense dispersal capabilities but nevertheless show local adaptation in several key traits. By combining population genomic analyses based on 12K single-nucleotide polymorphisms with larval dispersal patterns inferred using a biophysical ocean model, we show…
Plastic yielding of glass in high-pressure torsion apparatus
2018
International audience; Hardness measurements performed at room temperature have demonstrated that glass can flow under elevated pressure, whereas the effect of high pressure on glass rheology remains poorly quantified. Here, we applied a high-pressure torsion (HPT) apparatus to deform SCHOTT SF6 â glass and attempted to quantify the effect of pressure and temperature on the shear deformation of glass subjected to pressures from 0.3 GPa to 7 GPa and temperatures from 25 ℃ to 496 ℃. Results show that the plastic yield deformation was occurring during the HPT experiments on the SF6 glass at elevated temperature from 350 ℃ to 496 ℃. The yield stress of SF6 glass decreases with increasing tempe…
Pressure-induced instability of the fergusonite phase of EuNbO4 studied by in situ Raman spectroscopy, x-ray diffraction, and photoluminescence spect…
2020
In this article, we present high-pressure experimental investigations on EuNbO4, an interesting technologically important material, using synchrotron based x-ray powder diffraction, Raman spectroscopy, and europium photoluminescence measurements up to 39.2, 31.6, and 32.4 GPa, respectively. All three techniques show the stability of the ambient monoclinic phase until 20 GPa. Beyond that, a pressure-induced structural phase transition takes place with the coexistence of two phases over a wide pressure range. The structure of the high-pressure phase has been determined as orthorhombic (space group: Imma) with a volume discontinuity of nearly 9% at the transition indicating the nature of trans…
Tailoring the anomalous Hall effect of SrRuO$_3$ thin films by strain: a first principles study
2021
Motivated by the recently observed unconventional Hall effect in ultra-thin films of ferromagnetic SrRuO$_3$ (SRO) we investigate the effect of strain-induced oxygen octahedral distortion in the electronic structure and anomalous Hall response of the SRO ultra-thin films by virtue of density functional theory calculations. Our findings reveal that the ferromagnetic SRO films grown on SrTiO$_3$ (in-plane strain of $-$0.47$\%$) have an orthorhombic (both tilting and rotation) distorted structure and with an increasing amount of substrate-induced compressive strain the octahedral tilting angle is found to be suppressed gradually, with SRO films grown on NdGaO$_3$ (in-plane strain of $-$1.7$\%$…
Structure and dielectric properties of Na0.5Bi0.5TiO3-CaTiO3 solid solutions
2016
Despite wide studies of Na0.5Bi0.5TiO3, structure of this material and its connection with the observed physical properties still raise numerous questions due to mutually contradicting results obtained. Here, structure and dielectric properties of poled and unpoled Na0.5Bi0.5TiO3-CaTiO3 solid solutions are studied, projecting the obtained concentration dependence of structure and dielectric properties on pure Na0.5Bi0.5TiO3 as the end member of this material group. X-ray diffraction patterns for Na0.5Bi0.5TiO3-CaTiO3 solid solutions reveal dominating of an orthorhombic Pnma phase, even for the compositions approaching the end composition (Na0.5Bi0.5TiO3), whereas structure of pure Na0.5Bi0.…