Search results for "rotation"
showing 10 items of 935 documents
Contactless Nanoparticle-Based Guiding of Cells by Controllable Magnetic Fields
2021
Peter Blümler,1 Ralf P Friedrich,2 Jorge Pereira,3 Olga Baun,1 Christoph Alexiou,2 Volker Mailänder3,4 1Institute of Physics, Johannes Gutenberg-University Mainz, Mainz, 55128, Germany; 2Department of Otorhinolaryngology, Head and Neck Surgery, Section of Experimental Oncology and Nanomedicine (SEON), Else Kröner-Fresenius-Stiftung-Professorship, Universitätsklinikum Erlangen, Erlangen, 91054, Germany; 3Department of Physical Chemistry, Max Planck Institute for Polymer Research, Mainz, 55128, Germany; 4Department of Dermatology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, 55131, GermanyCorrespondence: Peter Blümle…
Double-modulation sideband spectroscopy: μ0 and μ33 of silicon tetrafluoride
1992
Abstract The linear Stark effect in the ν 3 fundamental of 28 SiF 4 has been investigated with IR-IR double resonance employing CO 2 laser sidebands at microwave modulation frequencies. The frequencies needed for the double-resonance experiment were generated from one laser line by a novel double-modulation technique. As a result, the parameter of the vibration-induced dipole moment was determined to μ 33 = −0.10288(56) D. For the centrifugal distortion moment in the ν 3 excited state the value μ 0 = 6.06(36) × 10 −7 D was found. From the Stark splitting in the vibrational ground state, μ 0 = 6.81(10) × 10 −7 was determined.
Numerical study of transient behaviour of molten zone during industrial FZ process for large silicon crystal growth
2004
The fully transient axisymmetric model has been developed for calculation of phase boundaries in large (up to 200 mm diameter) industrial floating zone (FZ) silicon single crystal growth with the needle-eye technique. The transient model is implemented in a specialized computer program. The model and program are based on a previously developed model and program for steady-state FZ process calculations. This transient approach allows studying of such substantially time-dependent process phases as the growth of the starting and ending cones of the crystal rod, which are particularly important for growth of large crystals in practice. Numerous calculations are carried out and the results for r…
Crystal shape 2D modeling for transient CZ silicon crystal growth
2013
Abstract A non-stationary axisymmetric model of Czochralski silicon single crystal growth is presented. The model describes transient behavior of crystal–melt, melt–gas and crystal–gas interfaces in connection with PID-based control of crystal diameter by changing crystal pulling velocity and heater power. To calculate significant crystal shape changes, unstructured finite element mesh is used in crystal and melt together with automatic element size control. Heater temperature changes are modeled with a simplified integral model. A numerical simulation example of start cone growth is given.
Microwave Fourier Transform Spectroscopy of Rovibrational Transitions in the ν 2 /ν 4 Dyads of Methane- 12 C and - 13 C
1987
The ν2/ν4 dyad-dyad spectra of 12CH4 and 13CH4 molecules in the (8÷20) GHz region have been predicted including line strengths. All transitions with γmax > 810-12 cm-1 have been observed directly using a MWFT spectrometer: six F-type transitions for 12CH4 and nine for 13CH4.
High-temperature emission spectroscopy of methane
2008
International audience; A high-enthalpy source (HES) has been developed in Rennes either to heat gases up to 2000K in local thermodynamic equilibrium (LTE) or to generate hypersonic expansions. The HES prototype has been associated with a high-resolution Bruker IFS 120 HR Fourier transform spectrometer to record emission spectra of hot gases, in LTE conditions. A series of emission spectra of methane has been obtained at 1005, 1365, 1485, 1625 and 1820K in the pentad spectral region located around 3000 cm1, at Doppler-limited resolution (0.02 cm1). Spectra have been corrected for the transmission function that strongly affects the infrared radiation emitted by the hot gas. Line-integrated a…
Research on the electrostatic properties of liquid dielectric mixtures
2007
Abstract This paper presents research results, which confirm the possibility of influencing the electrostatic charge tendency (ECT) of selected mixtures of purely insulating liquids. Tests were performed in a spinning disk system, where the factors influencing the value of the electrification current consisted of variable composition of the toluene–cyclohexane mixture, rotational speed, and a disk diameter. Liquid hydrocarbon mixtures displayed changes in ECT as well as classic insulation parameters such as resistivity and relative permittivity for concentration changes of the admixtures. These results can be used to assist the search for inhibitors of ECT and of aging processes in insulati…
Ultrahigh-Resolution Microwave Spectroscopy on TrappedYb+171Ions
1982
Laser frequency stabilization by magnetically assisted rotation spectroscopy
2011
Abstract We present a method of Doppler-free laser frequency stabilization based on magnetically assisted rotation spectroscopy (MARS) which combines the Doppler-free velocity-selective optical pumping (VSOP) and magnetic rotation spectroscopy. The stabilization is demonstrated for the atomic rubidium transitions at 780 nm. The proposed method is largely independent of stray magnetic fields and does not require any modulation of the laser frequency. Moreover, the discussed method allows one to choose between locking the laser exactly to the line center, or with a magnetically-controlled shift to an arbitrary frequency detuned by up to several natural linewidths. This feature is useful in ma…
Unveiling the Sulfur–Sulfur Bridge: Accurate Structural and Energetic Characterization of a Homochalcogen Intermolecular Bond
2018
open 12 si MIUR “PRIN 2015” funds (Grant Number 2015F59J3R) By combining rotational spectroscopy in supersonic expansion with the capability of state-of-the-art quantum-chemical computations in accurately determining structural and energetic properties, the genuine nature of a sulfur–sulfur chalcogen bond between dimethyl sulfide and sulfur dioxide has been unveiled in a gas-jet environment free from collision, solvent and matrix perturbations. A SAPT analysis pointed out that electrostatic S⋅⋅⋅S interactions play the dominant role in determining the stability of the complex, largely overcoming dispersion and C−H⋅⋅⋅O hydrogen-bond contributions. Indeed, in agreement with the analysis of the…