Search results for "S2"
showing 10 items of 200 documents
Cs2 molekulas A~b kompleksa augstas izšķirtspējas spektroskopiskie pētījumi un elektroniskās struktūras analīze
2019
Šajā maģistra darbā veikts Cs2 molekulas 〖A^1∑〗_u^+ un 〖b 〗^3 Π_u stāvokļu kompleksa elektroniskās-svārstību-rotācijas struktūras pētījums pielietojot Furjē transformāciju spektroskopijas un lāzera inducētās fluorescences (LIF) metodes. 〖A^1∑〗_u^+ un 〖b 〗^3 Π_u stāvokļus raksturo spēcīga spin-orbitālā mijiedarbība, kuras rezultātā stāvokļi veido saistītu A~b kompleksu. Cs2 molekulas pētīšanai maģistra darbā pielietota LIF metode, izmantojot dažādas lāzeru sistēmas, kombinācijā ar Furjē transformāciju spektrometru (Bruker IFS-125HR). Eksperimentāli reģistrēti un analizēti Cs2 molekulas spektri pārejās no A~b kompleksa uz pamatstāvokli. Darbā aprakstīts spektru apstrādes process, kura rezultā…
The crystal structure of bacteriophage Qβ at 3.5 å resolution
1996
Abstract Background: The capsid protein subunits of small RNA bacteriophages form a T=3 particle upon assembly and RNA encapsidation. Dimers of the capsid protein repress translation of the replicase gene product by binding to the ribosome binding site and this interaction is believed to initiate RNA encapsidation. We have determined the crystal structure of phage Qβ with the aim of clarifying which factors are the most important for particle assembly and RNA interaction in the small phages. Results The crystal structure of bacteriophage Qβ determined at 3.5 a resolution shows that the capsid is stabilized by disulfide bonds on each side of the flexible loops that are situated around the fi…
HPLC-DAD-ESI-MS2analytical profile of extracts obtained from purple sweet potato after green ultrasound-assisted extraction
2016
International audience; Ultrasound pre-treatment (UAE) was applied to assist the extraction of valuable compounds (polyphenols (especially anthocyanins), and proteins) from purple sweet potato (PSP). Under optimum conditions (ultrasound time (40 min); supplementary hot extraction (80 °C) up to 120 min; pH: 2.5; ethanol concentration: 58%), the highest concentrations of polyphenols (3.877 mg/g), anthocyanins (0.293 mg/g), and proteins (0.753 mg/g) were found, with minimal specific energy consumption (8406 J/mg).Moreover, anthocyanin and non-anthocyanin polyphenols in PSP extract from optimized extraction temperature were identified using HPLC-DAD-ESI-MS2. The major identified anthocyanins we…
Malliavin Calculus and Skorohod Integration for Quantum Stochastic Processes
2000
A derivation operator and a divergence operator are defined on the algebra of bounded operators on the symmetric Fock space over the complexification of a real Hilbert space $\eufrak{h}$ and it is shown that they satisfy similar properties as the derivation and divergence operator on the Wiener space over $\eufrak{h}$. The derivation operator is then used to give sufficient conditions for the existence of smooth Wigner densities for pairs of operators satisfying the canonical commutation relations. For $\eufrak{h}=L^2(\mathbb{R}_+)$, the divergence operator is shown to coincide with the Hudson-Parthasarathy quantum stochastic integral for adapted integrable processes and with the non-causal…
On rural development of NUTS 2 and 3: a non parametric approach of distribution dynamics analysis
2008
This work presents a study about dynamics of territorial gaps in agriculture between EU NUTS 2 and 3 from three perspectives: agricultural production model, rural development and productivity. Our choice of methodology is driven by two considerations. First of all, different performances in agriculture of EU areas may lead to multimodal distributions of indicators, and this implies that no significant average behaviour a parametric estimates refers to can be identified. Secondly, even if one wants to highlight multimodality within distributions, techniques like univariate density estimates can not catch intra-distribution dynamics which lead to the formation of "poles" of units showing a "s…
Cryopreservation of white mulberry (Morus alba L.) by encapsulation-dehydration and vitrification
2011
Shoot apices of in vitro-grown plantlets of white mulberry, Morus alba L. cv Florio, were cryopreserved using either encapsulation-dehydration or vitrification. For encapsulation-dehydration, alginate beads containing apices were dehydrated for 1, 3, 5 or 7 days in a liquid medium containing various sucrose concentrations (0.5, 0.75, 1.0 or 1.25 M). Bead desiccation was performed using silica gel for either 0, 4, 6, 8, 9 or 14 h. For vitrification, apices were directly immersed for either 5, 15, 30 or 60 min in a vitrification solution (PVS2). Following encapsulation-dehydration, treatment of alginate beads with 0.75 M sucrose was more effective in promoting re-growth of explants after imme…
Multiscale Investigation of the Structural, Electrical and Photoluminescence Properties of MoS2 Obtained by MoO3 Sulfurization
2022
In this paper, we report a multiscale investigation of the compositional, morphological, structural, electrical, and optical emission properties of 2H-MoS2 obtained by sulfurization at 800 °C of very thin MoO3 films (with thickness ranging from ~2.8 nm to ~4.2 nm) on a SiO2/Si substrate. XPS analyses confirmed that the sulfurization was very effective in the reduction of the oxide to MoS2, with only a small percentage of residual MoO3 present in the final film. High-resolution TEM/STEM analyses revealed the formation of few (i.e., 2–3 layers) of MoS2 nearly aligned with the SiO2 surface in the case of the thinnest (~2.8 nm) MoO3 film, whereas multilayers of MoS2 partially standing up with r…
Micrometer-size crystalline monolayer MoS2 domains obtained by sulfurization of molybdenum oxide ultrathin films
2023
In this work, the formation of micrometer-size crystalline monolayer (1L) MoS2 flakes with triangular shape and a central multilayer core is obtained by the sulfurization at 800 °C of pre-deposited ultrathin MoOx films (1.2–1.8 nm) on c-sapphire substrates. The thickness uniformity, crystalline quality, doping and strain distribution in the MoS2 flakes as a function of the initial MoOx thickness was evaluated by micro-Raman (μR) mapping. The excellent crystalline quality of the triangular 1L-MoS2 flakes was confirmed by micro-photoluminescence (μPL) maps, showing a very intense peak at ∼1.85 eV, that decreases in the central part, as expected for multilayers MoS2. A biaxial strain of ∼0.38–…
Robust Communications for the Underwater Internet of Things
2023
In recent years, the emergence of numerous applications and activities involving the underwater world have given rise to a new class of technologies that takes the name of Internet of Underwater Things (IoUT). Submarine activities such as remote control, pollution monitoring, data collection, disaster detection or even early warning and assisted navigation are just some of the main applications that require the use of underwater communication systems capable of providing connectivity between static and mobile nodes deployed at different depths. Generally, underwater communications employ audio signals which can propagate relatively far but are also significantly affected by Doppler distorti…
SNP variation in the bitter taste TAS2R38 gene evaluated in student populations of several italian universities and isolates
2007
People vary widely in their sensitivities to bitter compounds, but the all intercorrelation of these sensitivities is unknown. The study of genetic influences on bitter taste perception originated from the discovery in the 1930s that some individuals had taste to phenylthiocarbamide(PTC), whereas others found it extremely bitter. Subsequently, many studies were carried out on PTC and the structurally related compound propylthiouracil (PROP) to assess this viability and to determine the root causes. Initial family studies strongly suggested that PTC no tasting was due to a recessive allele in a single gene and heritability was estimated at 0,5. 55-85% of variation in PTC detection. The PTC ge…