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The RO VII is a monoplane with two 230 BMW engines mounted on top of the wing. It seats 4 passengers with room for a pilot and a mechanic in the cockpit.
This paper describes the use of an exact fast Fourier transform (FFT) method to prepare specified vibrational-rotational states of triatomic molecules. The method determines the Fourier coefficients needed to describe the coordinates and momenta of a vibrating-rotating triatomic molecule. Once the Fourier coefficients of a particular state are determined, it is possible to easily generate as many random sets of initial cartesian coordinates and momenta as desired. All the members of each set will correspond to the particular vibrational-rotational state selected. For example, in the case of the ground vibrational state of a non-rotating water molecule, the calculated actions of 100 sets of initial conditions produced actions within 0.001 h(bar) of the specified quantization values and energies within 5 cm(sup -1) of the semiclassical eigenvalue. The numerical procedure is straightforward for states in which all the fundamental frequencies are independent. However for states for which the fundamental frequencies become commensurate (resonance states), there are additional complications. In these cases it is necessary to determine a new set of "fundamental" frequencies and to modify the quantization conditions. Once these adjustments are made, good results are obtained for resonance states. The major problems are in labelling the large number of Fourier coefficients and the presence of regions of chaotic motion. Results are presented for the vibrational states of H2O and HCN and the ro-vibrational states of H2O.
A description is given of an algorithm for computing ro-vibrational energy levels for tetratomic molecules. The expressions required for evaluating transition intensities are also given. The variational principle is used to determine the energy levels and the kinetic energy operator is simple and evaluated exactly. The computational procedure is split up into the determination of one dimensional radial basis functions, the computation of a contracted rotational-bending basis, followed by a final variational step coupling all degrees of freedom. An angular basis is proposed whereby the rotational-bending contraction takes place in three steps. Angular matrix elements of the potential are evaluated by expansion in terms of a suitable basis and the angular integrals are given in a factorized form which simplifies their evaluation. The basis functions in the final variational step have the full permutation symmetries of the identical particles. Sample results are given for HCCH and BH3.
A three-dimensional time-dependent quantum dynamics approach using a recently developed ab initio potential energy surface is applied to study ro-vibrational excitation in N+N2 exchange scattering for collision energies in the range 2.1- 3.2 eV. State-to-state integral exchange cross sections are examined to determine the distribution of excited rotational states of N(sub 2). The results demonstrate that highly-excited rotational states are produced by exchange scattering and furthermore, that the maximum value of (Delta)j increases rapidly with increasing collision energies. Integral exchange cross sections and exchange rate constants for excitation to the lower (upsilon = 0-3) vibrational energy levels are presented as a function of the collision energy. Excited-vibrational-state distributions for temperatures at 2,000 K and 10,000 K are included.
Challenges in retrieving D- and E-region Ne from GPS-RO, New algorithm, Initial results, Implications for energetic electron precipitation (EEP).
At the Fukushima Daiichi Nuclear Power Station (NPS) site, concentrated waste water was stored in tanks, awaiting treatment to remove radionuclides using various multi-nuclide removal systems. To accelerate the treatment for risk reductions of radiation dose and tank leakage, we constructed reverse-osmosis (RO) concentrated water treatment equipment. The equipment consists of filters and five adsorbent vessels containing Cs-Sr simultaneous adsorbents with the removal ability of Sr being 1/1000(max) to 1/100(min), and the overall treatment capacity of 500 to 900 m{sup 3}/day. We developed a simulation code to calculate the Sr concentration of outlet water for each vessel in order to evaluate the bed life of the media. The simulation code makes it possible to plan when to change media in the vessels during the equipment operation. The successful treatment of concentrated waste water was conducted using the equipment from January to May 2015. Total amount of water treated was 82,194 m{sup 3}. (authors)
Machine learning models were developed for intermittent multi-mode operation of a wellhead reverse osmosis water purification and desalination system to predict salt passage, nitrate passage, and permeate flux. The models, based on long short-term memory (LSTM) recurrent neural network (RNN) architecture, included an attention mechanism to increase model performance in proximity of the regulatory limit for nitrate. Training and testing of the models for the Startup, Production, Shutdown and Flushing operational modes were based on operational data (consisting of 22 process variables per data sample) acquired every 2–5 s over a six-month period. The significant sets of model input attributes for the different operational modes were assessed via Spearman ranking correlation, Self-Organizing Map (SOM) analysis and feed forward feature selection (FFFS). Although the variability of nitrate passage, salt passage and permeate flux was significant over the four operational modes, prediction performance for the three outcomes were with R2 and Average Absolute Relative Error (AARE) of 0.78–0.95 and 2.96–6.16 %, respectively. Model updates post membrane elements replacement demonstrated similar levels of prediction accuracy. The study results suggest that there is merit in exploring the utility of multi-mode models for sensor fault detection, data imputation, and for potential use in model-predictive control.
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We analyzed a thousand visible spectra of Fulcher-α band measured for divertor plasmas in Large Helical Device. With a coronal model and Bayesian inference, the population distribution of hydrogen molecule in the electronic ground state was estimated. The non-thermal population distribution was recovered with a two-temperature model, which has two sets of rotational and vibrational temperatures, as well as their mixture coefficient. The lower rotational temperature significantly changes according to the plasma parameters. Its nearly linear dependence on the electron density was found, which is consistent with previous works. The lower vibrational temperature also shows a small density dependence, as reported by a previous work. On the other hand, the higher rotational and vibrational temperatures as well as the mixture coefficient only show slight changes over the broad range of plasma parameters. These population parameters show a significant correlation; with higher electron density, all the temperatures and the fraction of the higher-temperature component increase simultaneously. In conclusion, this suggests that the electron impact plays an important role to determine the population distribution.
EDGE2D-EIRENE profiles characteristic for low recycling, high recycling and detached plasmas are postprocessed applying a vibrationally resolved collisional radiative (CR) model based on the Yacora solver to predict excited state densities and thus the molecular Lyman-, Werner- and Fulcher band emission intensities. These emission intensities are compared to predictions from the AMJUEL database standardly used in EIRENE. Lower Fulcher band and higher Lyman- and Werner band emission is predicted by the Yacora model in comparison to AMJUEL suggesting that inconsistent results from model based evaluation of measured spectra are expected depending on which model and molecular emission band is considered. The implications on detachment rate predictions are discussed.
A published ab initio-based potential energy surface and newly constructed dipole moment surface of acetylene have been used to compute vibrational band intensities. The line intensity calculations employed the variational nuclear motion code WAVR4 for computation of wave functions and energy levels, and a newly developed code DIPOLE4 for computation of dipole transitions. Owing to the high computational cost of J>0 transitions using direct variational methods only J=0 and J=1 states and transitions have been computed variationally. The intensities of J>1 transitions were extrapolated from J=0 and J=1 using Honl-London coefficients. The resulting effective rotational constants B and transition intensities are compared with experimental data for the (3 nu(4)+nu(5)) combination band, the nu(3) and the nu(5) fundamental band. The prospects of using this procedure for extensive calculations of a hot line list, important for cool stars and extrasolar planets are discussed.
We present high-resolution near-infrared spectra of {beta} Pictoris-a nearby young star with a debris disk. Fundamental low-J CO absorption lines are detected and strict upper limits are placed on the flux of v = 2-1 low-J CO emission lines. The limit on the UV fluorescent emission flux in the v = 2-1 lines is used to place a tight constraint on the inner extent of the CO gas. Assuming H I is the primary collision partner, the sub-thermal population of the low-J v = 0 rotational levels constrains the density of the gas in the disk to n{sub H} = (2.5{sup +7.1}{sub -1.2}) x 10{sup 5} cm{sup -3}. If the distribution of hydrogen follows that of the other metals in the disk, we find that the mass of the gas in the disk is 0.17{sup +0.47}{sub -0.08} M{sub +}. We compare this mass to the gas mass necessary to brake the metals in the disk through ion-neutral reactions.
The protonated argon ion, {sup 36}ArH{sup +}, was recently identified in the Crab Nebula from Herschel spectra. Given the atmospheric opacity at the frequency of its J = 1-0 and J = 2-1 rotational transitions (617.5 and 1234.6 GHz, respectively), and the current lack of appropriate space observatories after the recent end of the Herschel mission, future studies on this molecule will rely on mid-infrared observations. We report on accurate wavenumber measurements of {sup 36}ArH{sup +} and {sup 38}ArH{sup +} rotation-vibration transitions in the v = 1-0 band in the range 4.1-3.7 μm (2450-2715 cm{sup –1}). The wavenumbers of the R(0) transitions of the v = 1-0 band are 2612.50135 ± 0.00033 and 2610.70177 ± 0.00042 cm{sup –1} (±3σ) for {sup 36}ArH{sup +} and {sup 38}ArH{sup +}, respectively. The calculated opacity for a gas thermalized at a temperature of 100 K and with a linewidth of 1 km s{sup –1} of the R(0) line is 1.6 × 10{sup –15} × N({sup 36}ArH{sup +}). For column densities of {sup 36}ArH{sup +} larger than 1 × 10{sup 13} cm{sup –2}, significant absorption by the R(0) line can be expected against bright mid-IR sources.
In 1950 Purcell and Ramsey suggested that the electron might have a CP-violating electric dipole moment (e-EDM) proportional to its spin angular momentum. This possibility initiated an ongoing hunt for the e-EDM that has been spurred on by the recognition of the importance of CP-violation to the formation of a matter-dominated universe[2] as well as a difference in magnitude of the Supersymmetric and Standard Model[4] prediction for its value. The current limit on the e-EDM is 1.6E 27.cm as determined in a Ramsey beam resonance study of the Tl atom. The PbF molecule provides a unique opportunity to measure the e-EDM. The molecules odd electron, heavy mass, and large internal field combine to give it an intrinsic sensitivity to an e-EDM that is over three orders of magnitude bigger than that of the Tl atom. In addition to this increased intrinsic sensitivity, the ground state of the PbF molecule allows for a "magic" electric field at which the magnetic moment vanishes[7]. All of these advantages create an opportunity to significantly lower the current limit on the e-EDM. These advantages can only be realized if an intense source of ground-state PbF molecules can be created and detected with high efficiency. The scope of this project is to (1) create a rotationally cold molecular beam source of PbF, (2) achieve a continuous ionization scheme for sensitive state selective detection of the PbF molecule.
Organic peroxy (ROO•) and hydroperoxy (•QOOH) radicals are key reactive intermediates that are formed via the oxidation of volatile organic compounds during combustion or in the Earth’s atmosphere. Their primary fate is continued unimolecular decay or bimolecular chemistry, the relative branching for which is heavily structure- and temperature-dependent. This article outlines a combined single- and multi-reference quantum chemical study to characterize the near-UV accessible electronically excited states of the prototypical ROO• and •QOOH intermediates, tert-butyl peroxy and hydroperoxy-tert-butyl radicals—the ground-state chemistries of which have been well studied both experimentally and computationally. Additionally, we simulate the electronic absorption profiles of these ROO• and •QOOH intermediates with a variety of multi- and single-reference methods. The results show an interesting conformer dependence on the electronically excited-state character and electronic absorption maxima of •QOOH. The results show promise for electronic absorption spectroscopy to be used as a selected probe for determining •QOOH conformers. Additionally, electronic absorption may contribute to the daytime removal of long-lived •QOOH intermediates formed in the troposphere. We expect that our studies will motivate experiments on the electronic absorption spectra of experimentally achievable ROO• and •QOOH.