Molecular line opacity of LiCl in the mid-infrared spectra of brown dwarfs

We present a complete line list for the X 1Sigma+ electronic ground state of LiCl computed using fully quantum-mechanical techniques. This list includes transition energies and oscillator strengths in the spectral region 0.3-39,640.7 cm-1 for all allowed rovibrational transitions in absorption within the electronic ground state. The calculations were performed using an accurate hybrid potential constructed from a spectral inversion fit of experimental data and from recent multi-reference single- and double-excitation configuration interaction calculations. The line list was incorporated into the stellar atmosphere code PHOENIX to compute spectra for a range of young to old T dwarf models. The possibility of observing a signature of LiCl in absorption near 15.8 microns is addressed and the proposal to use this feature to estimate the total lithium elemental abundance for these cool objects is discussed.Comment: 8 pages, 2 figures, 1 table. Accepted for publication in ApJ 613, Sept. 20 200

Electric-field noise from carbon-adatom diffusion on a Au(110) surface: first-principles calculations and experiments

The decoherence of trapped-ion quantum gates due to heating of their motional modes is a fundamental science and engineering problem. This heating is attributed to electric-field noise arising from the trap-electrode surfaces. In this work, we investigate the source of this noise by focusing on the diffusion of carbon-containing adsorbates on the surface of Au(110). We show by density functional theory, based on detailed scanning probe microscopy, how the carbon adatom diffusion on the gold surface changes the energy landscape, and how the adatom dipole moment varies with the diffusive motion. A simple model for the diffusion noise, which varies quadratically with the variation of the dipole moment, qualitatively reproduces the measured noise spectrum, and the estimate of the noise spectral density is in accord with measured values.Comment: 8 pages, 6 figure

Технология проведения капитального ремонта магистрального газопровода "Нижневартовский газоперерабатывающий завод-Парабель"

Объектом исследования является магистрального газопровода "Нижневартовский газоперерабатывающий завод-Парабель". Цель работы: изучение методов капитального ремонта магистрального газопровода. В процессе исследования проводились расчет толщины стенки газопровода, определение пропускной способности. Рассмотрены вопросы разработки траншеи, прокладки, монтажа газопровода, проведение пневматических испытаний. . Проведены мероприятия по охране труда и безопасности строительства, охране окружающей среды.The object of research is the main gas pipeline "Nizhnevartovsk gas processing plant-Parabel". The purpose of the work: to study the methods of capital repairs of the main gas pipeline. In the course of the study, the calculation of the wall thickness of the gas pipeline and the determination of the throughput capacity were carried out. The issues of trench development, gas pipeline laying, installation, and pneumatic testing are considered. . Measures on labor protection and construction safety, environmental protection were carried out

The Molecular Line Opacity of MgH in Cool Stellar Atmospheres

A new, complete, theoretical rotational and vibrational line list for the A-X electronic transition in MgH is presented. The list includes transition energies and oscillator strengths for all possible allowed transitions and was computed using the best available theoretical potential energies and dipole transition moment function with the former adjusted to account for experimental data. The A-X line list, as well as new line lists for the B'-X and the X-X (pure rovibrational) transitions, were included in comprehensive stellar atmosphere models for M, L, and T dwarfs and solar-type stars. The resulting spectra, when compared to models lacking MgH, show that MgH provides significant opacity in the visible between 4400 and 5600 Angstrom. Further, comparison of the spectra obtained with the current line list to spectra obtained using the line list constructed by Kurucz (1993) show that the Kurucz list significantly overestimates the opacity due to MgH particularly for the bands near 5150 and 4800 Angstrom with the discrepancy increasing with decreasing effective temperature.Comment: 10 pages, 4 figures, 3 table

Spiral Chain O4 Form of Dense Oxygen

Oxygen is in many ways a unique element: the only known diatomic molecular magnet and the capability of stabilization of the hitherto unexpected O8 cluster structure in its solid form at high pressure. Molecular dissociations upon compression as one of the fundamental problems were reported for other diatomic solids (e.g., H2, I2, Br2, and N2), but it remains elusive for solid oxygen, making oxygen an intractable system. We here report the theoretical prediction on the dissociation of molecular oxygen into a polymeric spiral chain O4 structure (\theta-O4) by using first-principles calypso method on crystal structure prediction. The \theta-O4 stabilizes above 2 TPa and has been observed as the third high pressure phase of sulfur (S-III). We find that the molecular O8 phase remains extremely stable in a large pressure range of 0.008 - 2 TPa, whose breakdown is driven by the pressure-induced instability of a transverse acoustic phonon mode at zone boundary, leading to the ultimate formation of \theta-O4. Remarkably, stabilization of \theta-O4 turns oxygen from a superconductor into an insulator with a wide band gap (approximately 5.9 eV) originating from the sp3-like hybridized orbitals of oxygen and the localization of valence electrons. (This is a pre-print version of the following article: Li Zhu et al, Spiral chain O4 form of dense oxygen, Proc. Natl. Acad. Sci. U.S.A. (2011), doi: 10.1073/pnas.1119375109, which has been published online at http://www.pnas.org/content/early/2011/12/27/1119375109 .)Comment: 13 apages, 3 figure

Stability of tryptophan during food processing and storage: 1. Comparative losses of tryptophan, lysine and methionine in different model systems

1. The stability of tryptophan was evaluated in several different food model systems using a chemical method (high pressure liquid chromatography after alkaline-hydrolysis) and rat assays. Losses of tryptophan were compared with the losses of lysine and methionine. 2. Whey proteins stored in the presence of oxidizing lipids showed large losses of lysine and extensive methionine oxidation but only minor losses of tryptophan as measured chemically. The observed decrease in bioavailable tryptophan was explained by a lower protein digestibility. 3. Casein treated with hydrogen peroxide to oxidize all methionine to methionine sulphoxide showed a 9% loss in bioavailable tryptophan. 4. When casein was reacted with caffeic acid at pH 7 in the presence of monophenol monooxygenase (tyrosinase; EC 1.14.18.l), no chemical loss of tryptophan occurred, although fluorodinitrobenzene-reactive lysine fell by 23%. Tryptophan bioavailability fell IS%, partly due to an 8% reduction in protein digestibility. 5. Alkali-treated casein (0.15 M-sodium hydroxide, 80°,4 h) did not support rat growth. Chemically-determined tryptophan, available tryptophan and true nitrogen digestibility fell 10, 46 and 23% respectively. Racemization of tryptophan was found to be 10% (D/(D+L)). 6. In whole-milk powder, which had undergone ‘early' or ‘advanced' Maillard reactions, tryptophan, determined chemically or in rat assays, was virtually unchanged. Extensive lysine losses occurred. 7. It was concluded that losses of tryptophan during food processing and storage are small and of only minor nutritional importance, especially when compared with much larger losses of lysine and the more extensive oxidation of methionin

Strengthening Competence of Therapists-in-Training in the Treatment of Health Anxiety (Hypochondriasis): Validation of the Assessment of Core CBT Skills (ACCS)

Although the observation and assessment of psychotherapeutic competences is central to training, supervision, patient care, quality control, and life‐long practice, structured instruments are used only occasionally. In the current study, an observation‐based tool for the Assessment of Core CBT Skills (ACCS) was translated into German and adapted, and its psychometric properties were pilot evaluated. Competence of therapists‐in‐training was assessed in a random sample of n = 30 videos on cognitive‐behavioral therapy including patients diagnosed with hypochondriasis. Two of three raters independently assessed the competences demonstrated in the entire, active treatment sessions (n = 60). In our sample, internal consistency was excellent, and interrater reliability was good. Convergent validity (Cognitive Therapy Scale) and discriminant validity (Helping Alliance Questionnaire) were within the expected ranges. The ACCS total score did not significantly predict the reduction of symptoms of hypochondriasis, and a one‐factorial structure of the instrument was found. By providing multiple opportunities for feedback, self‐reflection and supervision, the ACCS may complement current tools for the assessment of psychotherapeutic competences and importantly, support competence‐based training and supervision

The Molecular Continuum Opacity of MgH in Cool Stellar Atmospheres

The opacity due to photodissociation of 24MgH is investigated in the atmospheres of cool stars. The lowest two electronic transitions A 2Pi -- X 2Sigma+ and B' 2Sigma+ -- X 2 Sigma+ are considered where the cross sections for the latter were published previously (Weck, Stancil, & Kirby 2002) while the former are presented in this work. Model atmospheres calculated with the PHOENIX code are used to investigate the effect of the photodissociation opacity on spectra of cool stars. The A -- X photodissociation cross sections are obtained using a combination of ab initio and experimentally derived potential curves and dipole transition moments. Partial cross sections have been evaluated over the accessible wavelength range 1770-4560 Angstrom for all rotational transitions from the vibrational levels v''=0-11. Assuming a Boltzmann distribution of the rovibrational levels of the X 2Sigma+ state, LTE photodissociation cross sections are presented for temperatures between 1000 and 5000 K. Shape resonances, arising from rotational predissociation of quasi-bound levels of the A 2Pi state near threshold, characterize the LTE photodissociation cross sections. A sum rule is proposed as a check on the accuracy of the photodissociation calculations.Comment: 9 pages, 8 figure