Search results for "Rota"
showing 10 items of 2706 documents
Pirkstiņrotaļas un rotaļas ar priekšmetiem 3- 4 gadus vecu bērnu griešanas prasmes sekmēšanai
2019
Kvalifikācijas darba tēma ir, “Pirkstiņrotaļas un rotaļas ar priekšmetiem 3-4 gadus vecu bērnu griešanas prasmes sekmēšanai”. Darba mērķis ir teorētiski analizēt un praktiski pētīt, kā pirkstiņrotaļu un rotaļu ar priekšmetiem pielietošana sekmē 3-4 gadus vecu bērnu griešanas prasmes. Mērķa sasniegšanai tika izvirzīti vairāki uzdevumi: 1. Analizēt pedagogu un psihologu atziņas par 3-4 gadus vecu bērnu attīstību un raksturot griešanas prasmes. 2.Analizēt pedagogu atziņas par rotaļu, pirkstiņrotaļu pētījuma kontekstā. 3.Veikt pētījumu par griešanas prasmju sekmēšanu rotaļā. Darba pirmajā daļā teorētiski tiek analizēta pedagogu un psihologu atziņas par bērna attīstības īpatnībām vidējā pirmskol…
Asymptotic behavior of global solutions of aerotaxis equations
2019
Abstract We study asymptotic behavior of global solutions of one-dimensional aerotaxis model proposed in Knosalla and Nadzieja (2015) [9] .
Mathematical modelling of the feed rod shape in floating zone silicon crystal growth
2017
Abstract A three-dimensional (3D) transient multi-physical model of the feed rod melting in the floating zone (FZ) silicon single-crystal growth process is presented. Coupled temperature, electromagnetic (EM), and melt film simulations are performed for a 4 inch FZ system, and the time evolution of the open melting front is studied. The 3D model uses phase boundaries and parameters from a converged solution of a quasi-stationary axisymmetric (2D) model of the FZ system as initial conditions for the time dependent simulations. A parameter study with different feed rod rotation, crystal pull rates and widths of the inductor main slit is carried out to analyse their influence on the evolution …
System for control of polarization state of light and generation of light with continuously rotating linear polarization
2019
We present a technique for generating light in an arbitrary polarization state. The technique is based on interference of two orthogonally polarized light beams, whose amplitudes and phases are controlled with a Mach-Zehnder inteferometer with acousto-optic modulators (AOMs) placed in each arm. We demonstrate that via control over amplitudes, phases, and frequencies of acoustic waves driving the AOMs, any polarization state can be synthesized. In particular, we demonstrate generation of linearly polarized light, whose polarization plane continuously rotates at a rate from 1 kHz to 1 MHz. Such light finds applications in science (e.g., investigations of Bloch-Siegert effect) and technology (…
Spontaneous order in ensembles of rotating magnetic droplets
2019
Ensembles of elongated magnetic droplets in a rotating field are studied experimentally. In a given range of field strength and frequency the droplets form rotating structures with a triangular order - rotating crystals. A model is developed to describe ensembles of several droplets, taking into account the hydrodynamic interactions between the rotating droplets in the presence of a solid wall below the rotating ensemble. A good agreement with the experimentally observed periodic dynamics for an ensemble of four droplets is obtained. During the rotation, the tips of the elongated magnetic droplets approach close to one another. An expression is derived that gives the magnetic interaction be…
Localized domain wall nucleation dynamics in asymmetric ferromagnetic rings revealed by direct time-resolved magnetic imaging
2016
We report time-resolved observations of field-induced domain wall nucleation in asymmetric ferromagnetic rings using single direction field pulses and rotating fields. We show that the asymmetric geometry of a ring allows for controlling the position of nucleation events, when a domain wall is nucleated by a rotating magnetic field. Direct observation by scanning transmission x-ray microscopy (STXM) reveals that the nucleation of domain walls occurs through the creation of transient ripplelike structures. This magnetization state is found to exhibit a surprisingly high reproducibility even at room temperature and we determine the combinations of field strengths and field directions that all…
Exotic SiO(2)H(2) Isomers: Theory and Experiment Working in Harmony.
2016
Replacing carbon with silicon can result in dramatic and unanticipated changes in isomeric stability, as the well-studied CO2H2 and the essentially unknown SiO2H2 systems illustrate. Guided by coupled-cluster calculations, three SiO2H2 isomers have been detected and spectroscopically characterized in a molecular beam discharge source using rotational spectroscopy. The cis,trans conformer of dihydroxysilylene HOSiOH, the ground-state isomer, and the high-energy, metastable dioxasilirane c-H2SiO2 are abundantly produced in a dilute SiH4/O2 electrical discharge, enabling precise structural determinations of both by a combination of isotopic measurements and calculated vibrational corrections. …
A Rotational Thermalization Model for the Calculation of Collisionally Narrowed Isotropic Raman-Scattering Spectra - Application to the Srs-N2 Q-Bran…
1986
Abstract A model for the calculation of collisionally narrowed isotropic. Raman scattering spectra is proposed. In this model, the rotational transition probabilities are calculated within the strong collision approximation, allowing the rotational energy transfer rates to be expressed in terms of the sole individual Q( J ) line broadening coefficients. These transfer rates satisfy both detailed balance principle and unitarity of the scattering matrix in contrast with most of the previous approaches. Under further approximation concerning the rotational distribution of the collisional frequency, simpler expressions for transfer rates are deduced, which do not satisfy necessarily both unitar…
High-resolution rovibrational spectroscopy of c-C3H2+: The ν7 C–H antisymmetric stretching band
2020
Abstract The ν 7 antisymmetric C–H stretching fundamental of c- C 3 H 2 + has been characterized in a cryogenic 22-pole ion trap by a novel type of action spectroscopy, in which the rovibrational excitation of c- C 3 H 2 + is detected as a slowing down of the low-temperature reaction c- C 3 H 2 + + H2 → C 3 H 3 + + H. Ninety-one rovibrational transitions with partly resolved fine structure doublets were measured in high resolution. Supported by high-level quantum chemical calculations, spectroscopic parameters were determined by fitting the observed lines with an effective Hamiltonian for an asymmetric rotor in a doublet electronic ground state, X ˜ A 1 2 , yielding a band origin at 3113.6…
Catalytic activity of biscobalt porphyrin-corrole dyads toward the reduction of dioxygen
2009
A series of biscobalt cofacial porphyrin-corrole dyads bearing mesityl substituents at the meso positions of the corrole ring were investigated as to their electrochemistry, spectroelectrochemistry, and CO binding properties in nonaqueous media and then applied to the surface of a graphite electrode and tested as electrocatalysts for the reduction of dioxygen to water or hydrogen peroxide in air-saturated aqueous solutions containing 1 M HClO(4). The catalytic reduction of O(2) with the same dyads was also investigated in the homogeneous phase using 1,1'-dimethylferrocene as a reductant in PhCN containing HClO(4). The examined compounds are represented as (PMes(2)CY)Co(2), where P = a porph…