Search results for "Meta"
showing 10 items of 21438 documents
Electronic structure and elasticity of two-dimensional metals of group 10 : A DFT study
2023
The discovery of two-dimensional (2D) iron monolayer in graphene pores stimulated experimental and computational material scientists to investigate low-dimensional elemental metals. There have been many advances in their synthesis, stability, and properties in the last few years. Inspired by these advancements, we investigated the electronic structure and elasticity of free-standing monolayers of group 10 elemental metals, viz. Ni, Pd, and Pt. Using density-functional theory (DFT), we explored the energetic, geometric, electronic, and elastic properties of hexagonal, honeycomb, and square lattice structures of each element, in both planar and buckled forms. Among planar configurations, the …
Tiokruunueetterien metallikompleksit
2012
Tämä LuK-tutkielma käsittelee tiokruunueetterien metallikomplekseja. Tarkemman tarkastelun kohteeksi on valittu pelkkiä rikkidonoreita sisältävien tiokruunueettereiden hopea-, kulta-, kupari-, palladium- ja platinakompleksit, jotka ovat lisäksi homoleptisiä eli eivät sisällä tiokruunueetterien lisäksi muita ligandeja. Tutkielmassa on keskitetty lähinnä kompleksien rakenteisiin ja koordinaatiokemiaan.
Unlocking mixed oxides with unprecedented stoichiometries from heterometallic metalorganic frameworks for the catalytic hydrogenation of CO 2
2021
[EN] Their complex surface chemistry and high oxygen lattice mobilities place mixed-metal oxides among the most important families of materials. Modulation of stoichiometry in mixed-metal oxides has been shown to be a very powerful tool for tuning optical and catalytic properties. However, accessing different stoichiometries is not always synthetically possible. Here, we show that the thermal decomposition of the recently reported metal-organic framework MUV-101(Fe, Ti) results in the formation of carbon-supported titanomaghemite nanoparticles with an unprecedented Fe/Ti ratio close to 2, not achievable by soft-chemistry routes. The resulting titanomaghemite phase displays outstanding catal…
Alkyl-Substituted Aminobis(phosphonates) : Efficient Precipitating Agents for Rare Earth Elements, Thorium, and Uranium in Aqueous Solutions
2021
The efficient and environmentally sustainable separation process for rare earth elements (REE), especially for adjacent lanthanoids, remains a challenge due to the chemical similarity of REEs. Tetravalent actinoids, thorium, and traces of uranium are also present in concentrates of REEs, making their separation relevant. This study reports six simple water-soluble aminobis(phosphonate) ligands, RN[CH2P(O)(OH)2]2 (1 R = CH2CH3, 2 R = (CH2)2CH3, 3 R = (CH2)3CH3, 4 R = (CH2)4CH3, 5 R = (CH2)5CH3, 6 R = CH2CH(C2H5)(CH2)3CH3) as precipitating agents for REEs, Th, and U, as well as gives insight into the coordination modes of the utilized ligands with REEs at the molecular level. Aminobis(phospho…
The role of motor system in action-related language comprehension in L1 and L2: An fMRI study
2018
The framework of embodied cognition has challenged the modular view of a language-cognition divide by suggesting that meaning-retrieval critically involves the sensory-motor system. Despite extensive research into the neural mechanisms underlying language-motor coupling, it remains unclear how the motor system might be differentially engaged by different levels of linguistic abstraction and language proficiency. To address this issue, we used fMRI to quantify neural activations in brain regions underlying motor and language processing in Chinese-English speakers’ processing of literal, metaphorical, and abstract language in their L1 and L2. Results overall revealed a response in motor ROIs …
Developing a metatheoretical framework for second language development : a cultural-historical theory and dynamic systems theory perspective
2017
The main aim of this article-based dissertation is to construct and articulate a dialectical metatheoretical architecture for the study of second language development termed Purposive-Historical Systems Theory (PHiST) invoking, inter alia, the axiomatic imperatives of dynamic systems theory (DST), Vygotskian cultural-historical theory (CHT), and Pepperian root metaphor theory (RMT). Specifically, it primarily purports, first, to demonstrate the tenability of a dialectical synthesis of DST and CHT; second, to philosophize on the fundamental contours of PHiST; third, to apply a novel metatheoretical perspective, as a quintessential example, to reconceptualizing the seminal construct of the Zo…
“Olen tietoisempi, miten suomen kieli toimii” : havaintoja edistyneen suomenoppijan kielitaidosta täsmäopetushankkeen aikana
2018
Esittelemme tässä artikkelissa Turun yliopiston Täsmäopetusta edistyneille suomenoppijoille ‑hanketta ja tarkastelemme sellaisia edistyneen suomenoppijan kielitaitoon liittyviä ilmiöitä, jotka nousivat esiin tarjoamamme täsmä- eli yksilöopetuksen aikana. nonPeerReviewed
Effect of topical alendronate in periodontal defects: systematic review and meta-analysis
2021
Momentum-space structure of surface states in a topological semimetal with a nexus point of Dirac lines
2016
Three-dimensional topological semimetals come in different variants, either containing Weyl points or Dirac lines. Here we describe a more complicated momentum-space topological defect where several separate Dirac lines connect with each other, forming a momentum-space equivalent of the real-space nexus considered before for helium-3. Close to the nexus the Dirac lines exhibit a transition from type I to type II lines. We consider a general model of stacked honeycomb lattices with the symmetry of Bernal (AB) stacked graphite and show that the structural mirror symmetries in such systems protect the presence of the Dirac lines, and also naturally lead to the formation of the nexus. By the bu…
Sand clams of Ganzirri marine coastal lagoon in Messina (Italy). Extraction and ICP-MS analysis
2008
This paper studies the possible forms or phases of heavy metals in sediments of a marine coastal lagoon, called Ganzirri, located in the Sicilian coast of the Messina’s strait by using sequential extraction. To reduce the extraction time of the Tessier method, the last step of speciation was carried out by mineralization in a microwave oven. Here we report the results of the distribution of As, Be, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, Se, Tl, V and Zn, in four fractions of sediments samples and the concentration of the same metals in clams. This study looked at three bivalve mollusc species, Tapes decussates, Chamelea gallina and Cardium edule, raised in the sediment considered and discussed the…