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Letteratura scientifica selezionata sul tema "Luminous Atmospheres"

Autore: Grafiati

Pubblicato: 3 maggio 2025

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Articoli di riviste sul tema "Luminous Atmospheres"

Shaviv, Nir J. "Extremely Luminous Atmospheres". International Astronomical Union Colloquium 169 (1999): 155–58. http://dx.doi.org/10.1017/s025292110007192x.

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AbstractWe present the effects that inhomogeneities have on radiating atmospheres. It is shown that nonuniformities in a medium induce a reduction of the effective opacity which subsequently increases the Eddington Luminosity. The most striking effect however that arises from the dependence of the opacity on the inhomogeneities, is the possibility of a phase transition, where the atmosphere energetically favors exciting horizontally propagating waves due to large fluxes.

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de Jager, Cornells, Joost Carpay, Alex de Koter, Hans Nieuwenhuijzen e Erik Schellekens. "Atmospheric dynamics of luminous stars". International Astronomical Union Colloquium 113 (1989): 211–20. http://dx.doi.org/10.1017/s0252921100004474.

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AbstractA review is given of data and theories on the motion fields in super and hypergiants with special reference to LBV’s. We show that the radiative momentum flux is incapable of driving the episodical bursts of mass loss of these stars, and that there are several indications that the LBV-phenomenon is hydrodynamically driven. The sum of turbulent and radiative accelerations in the atmospheres of the most luminous stars compensates the gravitational acceleration for stars near the Humphreys-Davidson limit. This explains their atmospheric near-instability. The motion field in the atmosphere of a typical LBV consists mainly of low-order gravity waves, while acoustic waves are rapidly damped. These gravitation waves may be stochastic rather than coherently ordered. These stochastic pulsations are assumed to be responsible for the LBV phenomenon.

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Iping, Rosina C., George Sonneborn e Derck L. Massa. "FUSE observations of Luminous Blue Variables". Symposium - International Astronomical Union 212 (2003): 208–9. http://dx.doi.org/10.1017/s0074180900212059.

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P Cyg, AG Car, HD 5980 and η Car were observed with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. FUSE covers the spectral range from 980 Å to 1187 Å at a resolution of 0.05 Å. In this paper we discuss the far-UV properties of these LBVs and explore their similarities and differences. The FUSE observations of P Cyg and AG Car, both spectral type B2pe, are very similar. The atmospheres of both η Car and HD 5980 appear to be somewhat hotter and have much higher ionization stages (Si iv, S iv, and P v) in the FUSE spectrum than P Cyg and AG Car. There is a very good agreement between the FUSE spectrum of P Cygni and the model atmosphere computed by John Hillier with his code cmfgen. The FUSE spectrum of η Car, however, does not agree very well with existing model spectra.

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Forman, W., C. Jones, A. Bogdan, R. Kraft, E. Churazov, S. Randall, M. Sun, E. O’Sullivan, J. Vrtilek e P. Nulsen. "Supermassive Black Hole feedback in early type galaxies". Proceedings of the International Astronomical Union 15, S359 (marzo 2020): 119–25. http://dx.doi.org/10.1017/s1743921320004081.

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AbstractOptically luminous early type galaxies host X-ray luminous, hot atmospheres. These hot atmospheres, which we refer to as coronae, undergo the same cooling and feedback processes as are commonly found in their more massive cousins, the gas rich atmospheres of galaxy groups and galaxy clusters. In particular, the hot coronae around galaxies radiatively cool and show cavities in X-ray images that are filled with relativistic plasma originating from jets powered by supermassive black holes (SMBH) at the galaxy centers. We discuss the SMBH feedback using an X-ray survey of early type galaxies carried out using Chandra X-ray Observatory observations. Early type galaxies with coronae very commonly have weak X-ray active nuclei and have associated radio sources. Based on the enthalpy of observed cavities in the coronae, there is sufficient energy to “balance” the observed radiative cooling. There are a very few remarkable examples of optically faint galaxies that are 1) unusually X-ray luminous, 2) have large dark matter halo masses, and 3) have large SMBHs (e.g., NGC4342 and NGC4291). These properties suggest that, in some galaxies, star formation may have been truncated at early times, breaking the simple scaling relations.

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Malik, Matej, Daniel Kitzmann, João M. Mendonça, Simon L. Grimm, Gabriel-Dominique Marleau, Esther F. Linder, Shang-Min Tsai e Kevin Heng. "Self-luminous and Irradiated Exoplanetary Atmospheres Explored withHELIOS". Astronomical Journal 157, n. 5 (11 aprile 2019): 170. http://dx.doi.org/10.3847/1538-3881/ab1084.

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Höfner, S., S. Bladh, B. Aringer e K. Eriksson. "Dynamic atmospheres and winds of cool luminous giants". Astronomy & Astrophysics 657 (gennaio 2022): A109. http://dx.doi.org/10.1051/0004-6361/202141224.

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Context. The winds observed around asymptotic giant branch (AGB) stars are generally attributed to radiation pressure on dust formed in the extended dynamical atmospheres of these long-period variables. The composition of wind-driving grains is affected by a feedback between their optical properties and the resulting heating due to stellar radiation. Aims. We explore the gradual Fe enrichment of wind-driving silicate grains in M-type AGB stars to derive typical values for Fe/Mg and to test the effects on wind properties and synthetic spectra. Methods. We present new radiation-hydrodynamical DARWIN models that allow for the growth of silicate grains with a variable Fe/Mg ratio and predict mass-loss rates, wind velocities, and grain properties. Synthetic spectra and other observables are computed a posteriori with the COMA code. Results. The self-regulating feedback between grain composition and radiative heating, in combination with quickly falling densities in the stellar wind, leads to low values of Fe/Mg, typically a few percent. Nevertheless, the new models show distinct silicate features around 10 and 18 microns. Fe enrichment affects visual and near-IR photometry moderately, and the new DARWIN models agree well with observations in (J − K) versus (V − K) and Spitzer color–color diagrams. The enrichment of the silicate dust with Fe is a secondary process, taking place in the stellar wind on the surface of large Fe-free grains that have initiated the outflow. Therefore, the mass-loss rates are basically unaffected, while the wind velocities tend to be slightly higher than in corresponding models with Fe-free silicate dust. Conclusions. The gradual Fe enrichment of silicate grains in the inner wind region should produce signatures observable in mid-IR spectro-interferometrical measurements. Mass-loss rates derived from existing DARWIN models, based on Fe-free silicates, can be applied to stellar evolution models since the mass-loss rates are not significantly affected by the inclusion of Fe in the silicate grains.

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Höfner, S., S. Bladh, B. Aringer e R. Ahuja. "Dynamic atmospheres and winds of cool luminous giants". Astronomy & Astrophysics 594 (ottobre 2016): A108. http://dx.doi.org/10.1051/0004-6361/201628424.

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Chakrabarty, Aritra, Sujan Sengupta e Mark S. Marley. "Polarization of Rotationally Oblate Self-luminous Exoplanets with Anisotropic Atmospheres". Astrophysical Journal 927, n. 1 (1 marzo 2022): 51. http://dx.doi.org/10.3847/1538-4357/ac4d33.

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Abstract The young self-luminous giant exoplanets are expected to be oblate in shape, owing to the high rotational speeds observed for some objects. Similar to the case of brown dwarfs, the thermal emission from these planets should be polarized by scatterings of molecules and condensate cloud particles, and the rotation-induced asymmetry of the planet’s disk would yield to net nonzero detectable polarization. Considering an anisotropic atmosphere, we present here a three-dimensional approach to estimating the disk-averaged polarization that arises due to the oblateness of the planets. We solve the multiple-scattering vector radiative transfer equations at each location on the planet’s disk and calculate the local Stokes vectors, and then calculate the disk-integrated flux and linear polarization. For a cloud-free atmosphere, the polarization signal is observable only in the visible wavelength region. However, the presence of clouds in the planetary atmospheres leads to a detectable amount of polarization in the infrared wavelength region where the planetary thermal emission peaks. Considering the different broadband filters of the SPHERE-IRDIS instrument of the Very Large Telescope, we present generic models for the polarization at different wavelength bands as a function of their rotation period. We also present polarization models for the exoplanets β Pic b and ROXs 42B b, as two representative cases that can guide future observations. Our insights into the polarization of young giant planets presented here would be useful for the upcoming polarimetric observations of the directly imaged planets.

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Dorfl, Ernst A., Michael U. Feuchtinger e Alfred Gautschy. "Nonlinear Pulsations of Luminous Blue Variables". International Astronomical Union Colloquium 176 (2000): 109–12. http://dx.doi.org/10.1017/s0252921100057262.

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AbstractWe present the results of various nonlinear radial pulsation calculations of LBVs with different luminosity to mass ratios. Depending on the stellar parameters, most of these objects undergo strongly non-adiabatic pulsations which can also modify their stellar atmospheres. In some cases part of the kinetic energy of the motions is transferred by shock waves into the atmospheric layers leading to an overall decrease or increase of the stellar radius. This results in different mean density accompanied by a change of the pulsational behavior which can be compared to the results of a linear stability analysis. We also find that regular pulsations can occur around a different equilibrium than the initial configuration which has been determined by stellar evolution calculations. In cases of even higher luminosity to mass ratios the linear stability analysis predicts several unstable modes and the nonlinear computations can exhibit rather irregular light curves. Due to the large non-adiabaticity of the pulsation the corresponding velocity curves still remain more regular, but show increasing amplitudes until the energy stored is released. The pulsations are far from equilibrium conditions and may also lead to a pulsationally driven mass loss for certain stellar parameters.

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Linsky, Jeffrey L. "What is the essential physics of mass loss from late-type stars?" Symposium - International Astronomical Union 122 (1987): 271–87. http://dx.doi.org/10.1017/s007418090015658x.

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In this review I consider what clues the data are providing us concerning the mass loss from late-type stars. I consider in turn the major classes of mass-loss mechanisms (thermally-driven winds, radiatively-driven winds, and wave-driven winds), and consider whether the empirical mass loss rates and other data are consistent with any of these mechanisms acting alone. It is likely that several mechanisms act together to produce the large mass loss rates in the Mira and non-pulsating M supergiants. Studies of the solar atmosphere suggest that thermal bifurcation driven by molecular condensation instabilities may play a critical role in cooling the atmospheres of luminous cool stars and forming silicate dust. It is possible that several metastable modes of atmospheric structure may exist for a given set of stellar parameters.

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Più fonti

Tesi sul tema "Luminous Atmospheres"

Atié, Michèle. "Perception des ambiances lumineuses d'architectures remarquables : analyse des impressions en situation réelle et à travers des photographies omnidirectionnelles dans un casque immersif". Electronic Thesis or Diss., Ecole centrale de Nantes, 2024. http://www.theses.fr/2024ECDN0047.

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Cette thèse s’inscrit au croisement des domaines des ambiances lumineuses, de la pédagogie architecturale, de la perception et de l’immersion. Elle se concentre principalement sur la conception et la mise en oeuvre d’une nouvelle méthodologie expérimentale ayant pour but d’évaluer la capacité des photographies statiques omnidirectionnelles stéréoscopiques HDR, projetées dans un casque immersif, à restituer fidèlement des impressions subjectives d’ambiances lumineuses vécues dans des architectures de référence. Une attention particulière est accordée à l’influence des opérateurs de mappage de tons (TMOs). La méthodologie développée comprend plusieurs étapes : la constitution d’une grille d’analyse des ambiances lumineuses de lieux remarquables basée sur des propos d'experts ; la mise en place d’une méthode de collecte de données in situ pour l’évaluation des ambiances lumineuses (questionnaire, relevés lumineux, captationsphotographiques omnidirectionnelles HDR) ; et la mise en place d’une méthode d’évaluation des ambiances lumineuses dans un casque immersif. Les résultats fournissent des connaissances sur les caractéristiques des ambiances lumineuses in situ de sept architectures remarquables et sur la fidélité de perception de chaque impression d’ambiance lumineusedans le casque immersif en fonction des TMOs. Ils mettent également en évidence le lien entre les impressions sélectionnées par les propos d’experts et celles évaluées in situ et dans le casque immersif. Ces connaissances sont utiles pour des applications pédagogiques futures en architecture
This thesis is at the crossroads of the fields of luminous atmospheres, architectural pedagogy, perception and immersion. It focuses on the design and implementation of a new experimental methodology for evaluating the ability of HDR stereoscopic omnidirectional static photographs, projected in an immersive Head-Mounted Display (HMD), to faithfully reproducesubjective impressions of luminous atmospheres experienced in reference architectural places. Specific consideration is given to the impact of tone mapping operators (TMOs). Our methodology involves several steps: designing a grid for analyzing the luminous atmospheres of iconic places based on expert judgement; implementing in situ data collection to assess luminous atmospheres (questionnaire, light measurements, HDR omnidirectional photographic recordings), and implementinga method for assessing luminous atmospheres in an HMD. The results provide knowledge about the characteristics of the in situ luminous atmospheres of seven iconic buildings and the perceptual fidelity of each luminous atmosphere’s impression in the HMD, depending on the TMOs. The findings also highlight the relationship between the impressions selected by the experts and those assessed in situ and in the HMD. This knowledge is useful for future pedagogical applications in architecture

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Romand, Frédéric. "Simulation de la signature infrarouge des phénomènes lumineux transitoires en moyenne atmosphère". Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS091/document.

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Encore jamais été observé, le rayonnement infrarouge moyen et lointain consécutif aux sprites a été prédit et serait lié à l’excitation des états vibrationnels de CO2. En sciences de l’atmosphère, la composition chimique peut être retrouvée par des méthodes de télédétection infrarouge. Pour la Défense, les émissions infrarouges naturelles peuvent causer de fausses alarmes à travers les systèmes de veille optronique satellitaires ou aéroportés. C’est pourquoi il est nécessaire de caractériser les émissions infrarouges des sprites. Pour cela, un modèle de cinétique plasma-vibrationnelle a été développé et couplé à un modèle de transfert radiatif atmosphérique. Celui-ci permet de simuler les effets énergétiques et chimiques consécutifs à la perturbation électrique des streamers, éléments constitutifs des sprites. Les signatures infrarouges évaluées devraient être détectables pour un observateur situé dans la stratosphère ou dans l’espace. Par ailleurs, les effets des incertitudes sur les principaux paramètres du modèle ont été quantifiés à travers une étude de sensibilité. Enfin, ces travaux ont permis de définir certaines spécifications instrumentales pour la mission HALESIS (High Altitude Luminous Events Studied by Infrared Spectro-imagery), qui aura pour but d’observer les sprites et autres phénomènes lumineux de moyenne atmosphère dans l’infrarouge
Even if it hasn’t been observed yet, the existence of emissions in the middle and far infrared following a sprite is suspected and could be related to vibrational excitation of CO2. In atmospheric sciences, the chemical composition can be retrieved through different remote sensing methods. For the Defense, natural infrared emissions could cause false alarms through airborne and spaceborne optronic detection systems. That is why it is necessary to characterize the infrared emissions of sprites. To do so, a plasma-vibrational kinetic model has been developed and coupled to an atmospheric radiative transfer model. This model allows evaluating the energetic and chemical effects following the electrical perturbation caused by the propagation of streamers, main constituent elements of sprites. The evaluated signatures could be detectable for an observer situated in the stratosphere or in space. Otherwise, the effects of the uncertainties on the principal parameters of the model have been quantified through a sensitivity analysis. Finally, this work allowed defining instrumental specifications for the future mission HALESIS (High Altitude Luminous Events Studied by Infrared Spectro-imagery), which will record hyperspectral infrared images of sprites and other middle atmosphere luminous events

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Romand, Frédéric. "Simulation de la signature infrarouge des phénomènes lumineux transitoires en moyenne atmosphère". Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS091.

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Bailey, Matthew A. "Investigating Characteristics of Lightning-Induced Transient Luminous Events Over South America". DigitalCommons@USU, 2010. http://digitalcommons.usu.edu/etd/667.

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Sprites, halos, and elves are members of a family of short-lived, luminous phenomena known as Transient Luminous Events (TLEs), which occur in the middle atmosphere. Sprites are vertical glows occurring at altitudes typically ranging from ~40 to 90 km. In video imagery they exhibit a red color at their top, with blue tendril-like structure at low altitudes. Elves are disk-like glows that occur at the base of the ionosphere, with diameters of ~100-300 km, and have very short lifetimes (~2-3 ms). Halos are diffuse glows that occur at low altitudes, have diameters <100 km, and have a duration that may last up to 10s of ms. A majority of the studies of TLEs have taken place over the Midwestern U.S. where they were first discovered. This area produces large thunderstorms, which in turn generate large lightning discharges that have been associated with the formation of TLEs. Studies have used the low frequency radiation that initiates with these strokes to study characteristics of these events. This low frequency radiation has been used to determine where large numbers of TLEs may occur. Extreme southern Brazil is a region of the globe believed to have many TLEs, but few studies on these phenomena. Two collaborative campaigns involving Utah State University proceeded in 2002-2003, and in 2006. Multiple TLE images were made, proving this is, indeed, a region of the globe where these types of events are prominent. In particular, one storm in February 2003 produced over 440 TLEs imaged by USU video cameras. Of these events, over 100 of them had associated halos. Statistical studies for halos previously had been performed in the U.S., but never abroad. Also, several events from the February storm have been associated with negative cloud to ground lightning, a surprising occurrence, as to date, less than a handful of such events have ever been witnessed or published. In analyzing the TLEs from this campaign, we have shown the halos are similar to those seen in the U.S., even though the storms may be somewhat different. Also, detailed analyses of the negative events show both temporal and spatial morphology heretofore never reported on.

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Kamogawa, Masashi. "Study of earthquake related electromagnetic and luminous phenomena in the atmosphere = Jishin ni kanrensuru taiki denji hakkō genshō no kenkyū /". Electronic version of summary, 2000. http://www.wul.waseda.ac.jp/gakui/gaiyo/2945.pdf.

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Lacour, Thomas. "Influence du statut azoté et du cycle lumineux diurne sur le métabolisme lipidique d'Isochrysis sp. (Haptophyceae)". Phd thesis, Aix-Marseille Université, 2010. http://tel.archives-ouvertes.fr/tel-00852596.

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Cette thèse présente différents cas d'acclimatation d'une espèce de phytoplancton (Isochrysis sp.) à des modifications de son environnement physico-chimique avec une attention particulière portée sur la composante lipidique de la réponse aux changements. Dans ce contexte nous avons étudié les lipides à la fois comme des produits (triacylglycerol) et des acteurs (glycolipides) de la photosynthèse. Tout d'abord, nous avons étudié l'influence de plusieurs types de limitation par l'azote sur la teneur en lipides neutres des algues. Nous avons montré que la relation entre la disponibilité de l'azote et la teneur en lipide n'était pas monotone et qu'elle présentait un caractère hystérétique. Les cellules d'Isochrysis sp. n'accumulent des lipides neutres que transitoirement lors du passage d'une croissance forte vers une croissance faible. Nous nous sommes ensuite intéressé aux relations qui existent entre le cycle nycthéméral et l'accumulation de réserves énergétiques sous forme de lipides et de sucres. Les réserves sont accumulées pendant le jour en disproportion du reste du carbone et consommées pendant la nuit pour alimenter la division cellulaire et la croissance nocturne. La carence en azote dans ces conditions nycthémérales ne provoque pas d'accumulations significatives de lipides. Les variations diurnes de la teneur en lipides neutres sont plus importantes que les variations obtenues en carence. A travers ces différentes expériences nous avons pu mettre en évidences les relations qui existaient entre l'environnement, la croissance, et l'accumulation de réserves. La compréhension de ces mécanismes a permis de déterminer les conditions environnementales qui favorisent la production d'huile en vue d'une utilisation biocarburant. Nous avons aussi étudié l'influence des conditions de croissance sur la composition des glycolipides des membranes des chloroplastes. Les résultats montrent que les changements de la teneur en MGDG, DGDG et SQDG et de l'insaturation des acides gras de ces lipides accompagnent les modifications d'activité photosynthétique des cellules en limitation azotée et en cycle Jour/Nuit.

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Amorim, Miguel David Santos. "Environmental analytical chemistry: development and comparison of simple chemiluminescent and bioluminescent methods to analyze air particulate samples". Master's thesis, 2016. http://hdl.handle.net/10451/35885.

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Trabalho Final de Mestrado Integrado, Ciências Farmacêuticas, Universidade de Lisboa, Faculdade de Farmácia, 2016
The harmful effects of atmospheric pollution’s particulate matter on the human organism have been proven and studied since a long time ago. Innumerous methods have been developed through time to test the composition of air particulate matter and its effect on the human body. A lot of reliable complex methods exist, but there seems to be a need for a simple, affordable, sensitive and accurate method that most laboratories could use to test their own air samples. Two simple methods were developed to analyze particulate matter samples in two highly polluted Italian cities – Quiliano and Vado Ligure, both from the region of Liguria – one chemiluminescent and one bioluminescent method. The chemiluminescent method was based on the reaction between luminol and peroxidase in the presence of oxidizing solution, producing an amount of light directly proportional to the amount of oxidizing compound in the sample. So luminol/enhancer and peroxidase solutions were added to the samples and the light emission was measured using a luminometer. The ability to determine samples’ toxicity is related with the major toxic effect of particulate matter being oxidative stress. By comparing the samples’ luminescence kinetics over time and their maximum signals to previously analyzed heavy metals’ samples we were able to identify the samples’ main compound and quantity’s order of magnitude. On the other hand, the bioluminescent method used naturally luminescent UCIBO bacteria – genetically modified Vibrio fischeri – to evaluate the toxic effect of the samples in living organisms. This way, highly luminescent bacteria were added directly to the samples and their pattern of luminescence signal was compared to healthy colonies, being the difference in luminescence maximum signal a direct proportion of the samples’ toxicity over bacteria. Both methods proved simple and fast to execute, affordable and sensitive. The bioluminescent method showed better accuracy than the chemiluminescent one (12.13% versus 21.50% mean standard deviation), even though both methods developed need improvements to ensure higher accuracy and become more reliable. A direct relation between both methods results was not possible to establish as while the chemiluminescent method focuses more on the amounts of oxidizing material in the samples, the bioluminescent one assesses their toxicity. A sample may have higher values of oxidizing components, giving higher values with the chemical method, and produce less toxic effects than another with lower amount of oxidizing materials, not displaying so high results with the biological method as the second sample. We concluded that both methods can and should be used together, in order to obtain more valuable and complete information about the air pollution samples.
Os efeitos nefastos da poluição atmosférica no corpo humano estão demonstrados e têm vindo a ser estudados há vários anos. Inúmeros métodos têm sido desenvolvidos para testar a composição das partículas aéreas e o seu efeito no corpo humano. Existem uma série de métodos complexos fiáveis, mas parece haver uma necessidade de um método que seja simples de executar, de baixo custo, preciso e sensível, que a maioria dos laboratórios possa utilizar para testar as suas amostras de partículas atmosféricas. Dois métodos simples para testar a poluição atmosférica de duas cidades italianas altamente poluídas – Quiliano e Vado Ligure, da região da Ligúria – foram desenvolvidos. Um método quimioluminescente e um bioluminescente. O método quimioluminescente baseou-se na reacção entre o luminol e a peroxidase, na presença de substâncias oxidantes, produzindo uma quantidade de luz directamente proporcional à quantidade de composto oxidante da amostra. Assim, soluções de luminol/intensificador e peroxidase foram adicionadas às amostras de poluição atmosférica, sendo a luz produzida medida através de um luminómetro. A capacidade para determinar o potencial tóxico das amostras deste método prende-se com o principal mecanismo de toxicidade da poluição atmosférica, o stress oxidativo. Ao comparar as cinéticas de luminescência das amostras e os seus picos de sinal com as de soluções padrão de metais pesados analisadas previamente foi possível identificar os principais componentes das amostras e a ordem de grandeza da sua quantidade. Por outro lado, o método bioluminescente utilizou bactérias UCIBO – Vibrio fischeri geneticamente modificadas – naturalmente luminescentes de forma a avaliar o efeito tóxico das amostras em organismos vivos. Assim sendo, bactérias altamente luminescentes foram adicionadas directamente às amostras de poluição aérea e o seu padrão de sinal foi comparado com o de colónias saudáveis, sendo a diferença entre os picos de ambos uma proporção directa da toxicidade exercida pelas amostras nas bactérias. Ambos os métodos se demonstraram fáceis e rápidos de executar, baratos e sensíveis. O método bioluminescente mostrou-se mais preciso que o quimioluminescente (12.13% versus 21.50% de desvio padrão médio), apesar de ambos os métodos necessitarem de melhorar a sua precisão para se tornarem mais fiáveis. Não foi possível estabelecer uma relação directa entre os resultados dos métodos, pois ao passo que o método quimioluminescente se foca mais na composição qualitativa e quantitativa das amostras, o bioluminescente avalia mais os efeitos tóxicos da amostra nos organismos. Uma determinada amostra pode possuir níveis mais altos de compostos oxidantes que uma segunda, produzindo resultados maiores com o método químico, mas ter efeitos tóxicos menos pronunciados, obtendo valores mais baixos de toxicidade com o métodos biológico. Concluímos que ambos os métodos podem e devem ser utilizados em conjunto, de forma a proporcionar uma melhor e mais completa informação sobre as amostras de poluição atmosférica.

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Libri sul tema "Luminous Atmospheres"

Kaufman, Donald. Color and light: Luminous atmospheres for painted rooms. New York: Clarkson Potter, 1999.

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United States. National Aeronautics and Space Administration., a cura di. Model atmosphere analysis of selected luminous B stars. Princeton, NJ: Princeton University, Dept. of Astrophysical Sciences ; [Washington, DC, 1994.

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Center, Goddard Space Flight, a cura di. Differential absorption lidar measurements of atmospheric water vapor using a pseudonoise code modulated AIGaAs laser. Greenbelt, Md: National Aeronautics and Space Administration, Goddard Space Flight Center, 1994.

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Bychkov, Vladimir. Natural and artificial Ball Lightning in the Earth’s atmosphere. LCC MAKS Press, 2021. http://dx.doi.org/10.29003/m2009.978-5-317-06572-0.

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Abstract (sommario):

Issues related to ball lightning of natural origin and its laboratory modeling in air are presented. The data on the main known researchers of these issues are given. Experiments on modeling long-lived luminous formations and artificial ball lightning are discussed. Observational data on ball lightning are presented. Methods of statistical analysis of observational data on ball lightning are considered. The theoretical models of natural ball lightning are briefly discussed. The book is aimed for senior students of physics and physics and technology departments of universities, as well as for scientists and engineers who deal with complex systems containing low-temperature plasma, plasma aerodynamics, geography and geophysics.

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Murray, John. Experimental Researches: On the Light and Luminous Matter of the Glow-Worm, the Luminosity of the Sea, the Phenomena of the Chameleon, the Ascent of the Spider into the Atmosphere, and the Torpidity of the Tortoise. Cambridge University Press, 2013.

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Capitoli di libri sul tema "Luminous Atmospheres"

Appenzeller, I. "The Role of Radiation Pressure in LBV Atmospheres". In Physics of Luminous Blue Variables, 195–204. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-1031-7_23.

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Kudritzki, R. P., A. Gabler, H. G. Groth, A. W. A. Pauldrach e J. Puls. "Model Atmospheres and Quantitative Spectroscopy of Luminous Blue Stars". In Physics of Luminous Blue Variables, 67–82. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-1031-7_8.

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de Groot, Mart, e Henny J. G. L. M. Lamers. "Observed evolutionary changes in the visual magnitude of the luminous blue variable P Cygni". In The Atmospheres of Early-Type Stars, 121. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/3-540-55256-1_289.

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Tsuji, T. "CO Molecule in Transition Region between Chromosphere and Cool Stellar Wind: A New Probe on the Outer Atmospheres of Cool Luminous Stars". In Circumstellar Matter, 377–78. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3887-8_92.

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de Jager, Cornelis, Joost Carpay, Alex de Koter, Hans Nieuwenhuijzen e Erik Schellekens. "Atmospheric Dynamics of Luminous Stars". In Physics of Luminous Blue Variables, 211–20. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-1031-7_25.

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Leitherer, Claus, David C. Abbott e Werner Schmutz. "Changes in the Atmospheric Structure of LBV’s During Eruptions". In Physics of Luminous Blue Variables, 109–16. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-1031-7_12.

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Leitherer, Claus, Werner Schmutz, David C. Abbott, Ana V. Torres-Dodgen, Wolf-Rainer Hamann e Ulf Wessolowski. "Atmospheric Models for LBV’s at Minimum and Maximum States". In Physics of Luminous Blue Variables, 285–86. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-1031-7_43.

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Bychkov, Vladimir L. "Long-Lived Luminous Formations (LLO), Ball Lightning (BL), and Their Researches". In Springer Atmospheric Sciences, 1–30. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-07861-3_1.

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Nieuwenhuijzen, Hans, e Cornelis de Jager. "Atmospheric Parameters and Accelerations in the Outer Parts of Luminous Hot Stars". In Physics of Luminous Blue Variables, 287–88. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-1031-7_44.

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Dupree, A. K. "New Clues to Atmospheric Heating Processes in Luminous Cool Stars". In Mechanisms of Chromospheric and Coronal Heating, 185–99. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-87455-0_39.

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Atti di convegni sul tema "Luminous Atmospheres"

Atié, Michèle, Céline Drozd, Toinon Vigier e Daniel Siret. "Luminous Atmospheres 360: Comparing VR HMDs and UHD Screens for Reproducing Architectural Daylight Atmospheres". In 2025 IEEE Conference on Virtual Reality and 3D User Interfaces Abstracts and Workshops (VRW), 1420–21. IEEE, 2025. https://doi.org/10.1109/vrw66409.2025.00356.

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Khatami, Reza, e Yiannis A. Levendis. "Soot Volume Fractions in Volatile Matter Envelope Flames of Bituminous Coal Particles in Air and Oxy-Fuel Combustion". In ASME 2013 Power Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/power2013-98163.

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This work calculated volume fractions of soot in volatile matter envelope flames which form around burning single particles of bituminous coal. Both conventional combustion in air and simulated oxy-fuel combustion, with oxygen mole fractions in the range of 20–40% in CO2, were studied. Particles of 75–90 μm were injected in a bench-scale, transparent drop-tube furnace (DTF), at wall temperatures of 1400K. Upon ignition, optical pyrometry and high-speed photography were implemented to optically diagnose the burning particles. The method of Timothy et al[1] was applied to determine the instantaneous spatially-average soot volume fraction in these envelop flames. Results showed that soot shell forming around the particle was thicker and more luminous in air than the shell forming at the same O2 concentration in CO2. The soot volume fraction was decreased when N2 in air was replaced by CO2. Average soot volume fraction in the envelope flames in air was in the order of 7×10−5, whereas it was in the range 3.5×10−5 – 5.0×10−5 in oxy-fuel atmospheres.

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Borisov, Boris D., Yurii Gridnev e Vladimir V. Belov. "Observation of self-luminous objects through scattering media". In Fifth International Symposium on Atmospheric and Ocean Optics, a cura di Vladimir E. Zuev e Gennadii G. Matvienko. SPIE, 1999. http://dx.doi.org/10.1117/12.337024.

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sun, kelin, Jingchuan Yang, Bing Zhang, Bo Li, Kaibin Liu e Chen Li. "Reducing transmitter’s luminous surface with integrated LED arrays for deep-sea wireless optical communication". In Atmospheric and Environmental Optics, a cura di Liang Xu, Jianguo Liu e Jian Gao. SPIE, 2023. http://dx.doi.org/10.1117/12.2646071.

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Kozak, L. V., A. Odzimek, A. E. Volvach, V. M. Ivchenko, P. M. Kozak e V. P. Lapchuk. "Observation and analysis of transient luminous events in the Earth's atmosphere". In 2014 24th International Crimean Conference "Microwave & Telecommunication Technology" (CriMiCo). IEEE, 2014. http://dx.doi.org/10.1109/crmico.2014.6959773.

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Lukin, Vladimir P., Nina N. Botugina, Oleg N. Emaleev e Peter A. Konyaev. "Experimental studies of the correlation of wave-front aberrations of a point coherent source and an extended luminous object". In XXIII International Symposium, Atmospheric and Ocean Optics, Atmospheric Physics, a cura di Oleg A. Romanovskii. SPIE, 2017. http://dx.doi.org/10.1117/12.2283001.

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Arnal, Etienne, Cedric Anthierens e Eric Bideaux. "Consideration of glare from daylight in the control of the luminous atmosphere in buildings". In 2011 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM). IEEE, 2011. http://dx.doi.org/10.1109/aim.2011.6027070.

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Sosnin, Eduard A., Evgenii K. Baksht, Vladimir S. Kuznetsov, Victor A. Panarin, Dmitrii S. Pechenitsyn, Victor S. Skakun e Victor F. Tarasenko. "Apokamp discharge as a laboratory analogue of the transient luminous events of middle atmosphere". In XIV International Conference on Pulsed Lasers and Laser Applications (AMPL-2019), a cura di Anton V. Klimkin, Victor F. Tarasenko e Maxim V. Trigub. SPIE, 2019. http://dx.doi.org/10.1117/12.2541527.

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Maryeva, O., V. Gvaramadze, A. Kniazev e L. Berdnikov. "Wray 15-906 low mass Luminous Blue Variable on a pre-supernova stage". In ASTRONOMY AT THE EPOCH OF MULTIMESSENGER STUDIES. Proceedings of the VAK-2021 conference, Aug 23–28, 2021. Crossref, 2022. http://dx.doi.org/10.51194/vak2021.2022.1.1.059.

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Evolutionary link between Red Supergiants and Luminous Blue variables is interesting, but still poorly understood. Wepresent the results of study of the Galactic candidate luminous blue variable Wray 15-906, revealed via detection of itsinfrared circumstellar shell (of ≈ 2 pc in diameter) with the Wide-ﬁeld Infrared Survey Explorer (WISE) and the HerschelSpace Observatory. Using the stellar atmosphere code CMFGEN and the Gaia parallax, we found that Wray 15-906 is arelatively low-luminosity, log(L/L ⊙ ) ≈ 5.4, star of temperature of 25 ± 2 kK. In the framework of single star evolution,the obtained results suggest that Wray 15-906 is a post-red supergiant star with initial mass of ≈ 25 M ⊙ and that beforeexploding as a supernova it could transform for a short time into a WN11h star. The presence of shell with mass 2.9±0.5 M ⊙indicates that Wray 15-906 has suﬀered substantial mass loss in the recent past.

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Nishita, Tomoyuki, Yasuhiro Miyawaki e Eihachiro Nakamae. "A shading model for atmospheric scattering considering luminous intensity distribution of light sources". In the 14th annual conference. New York, New York, USA: ACM Press, 1987. http://dx.doi.org/10.1145/37401.37437.

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