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Gotowe bibliografie tematyczne / Molecular jets

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Gotowa bibliografia na temat „Molecular jets”

Autor: Grafiati

Data publikacji: 4 czerwca 2021

Data aktualizacji: 1 lutego 2022

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Artykuły w czasopismach na temat "Molecular jets"

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Smith, Michael D., Roland Völker, Gerhard Suttner i Harold W. Yorke. "The Class 0 Outflow Hammered Out?" Symposium - International Astronomical Union 182 (1997): 303–12. http://dx.doi.org/10.1017/s0074180900061726.

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Dense molecular jets cutting through dense molecular clouds are simulated here using a ZEUS-type hydrodynamics code extended with molecular physics. H2 ‘hot snapshots’ and CO ‘historical views’ are nicely modelled with overdense uniform jets. Attention is drawn to some remaining hot problems: observed jet knots are bow shaped, bipolar outflows can be highly asymmetric, some proper motions within jets are enigmatically low and H2 excitation can be exceedingly uniform.We present the Hammer Jet, in which the nozzle introduces high velocity variations, as well as a strong ripping and spray action. Prominent jet bow shocks in H2 and CO emission lines are then produced. Wide tubular CO structures with concave bases show up. Proper motions are simulated. The asymmetries are modelled by jet break-out from a molecular core into a diffuse atomic environment.

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Hollenbach, David. "The Physics of Molecular Shocks in YSO Outflows". Symposium - International Astronomical Union 182 (1997): 181–98. http://dx.doi.org/10.1017/s0074180900061647.

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Shock waves light up the jets, winds and outflows around YSOs and diagnose the physical conditions and processes resident in these regions. This paper discusses the differences between the jet/wind shock and the ambient shock, between C shocks and J shocks, and between the shocks produced by pure jets and by collimated wide angle winds. Basic shock physics is briefly reviewed, with a special focus on the temperature structure in shocks and the Wardle instability of C shocks. Application is made to the origin of shocked H2 emission and to H2O masers.

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Hirano, Naomi, Paul P. T. Ho, Sheng-Yuan Liu, Hsien Shang, Chin-Fei Lee i Tyler L. Bourke. "EXTREME ACTIVE MOLECULAR JETS IN L1448C". Astrophysical Journal 717, nr 1 (7.06.2010): 58–73. http://dx.doi.org/10.1088/0004-637x/717/1/58.

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Snell, Ronald L. "Structure and kinematics of molecular jets". Canadian Journal of Physics 64, nr 4 (1.04.1986): 431–33. http://dx.doi.org/10.1139/p86-077.

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Observational studies of the structure and kinematics of the supersonic molecular gas in star-forming regions are reviewed. These studies have suggested that the bulk of the high-velocity gas may be ambient-cloud material swept up by a collimated stellar wind. The actual structures of these outflows, however, are poorly understood. One source that may provide a better understanding of molecular outflows is that in the nearby dark cloud L1551. New observations of this outflow are presented and discussed in context of the models proposed by Snell and Schloerb.

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Smith, M. D., i A. Rosen. "Hydrodynamic simulations of rotating molecular jets". Monthly Notices of the Royal Astronomical Society 378, nr 2 (21.06.2007): 691–700. http://dx.doi.org/10.1111/j.1365-2966.2007.11816.x.

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Tabone, B., B. Godard, G. Pineau des Forêts, S. Cabrit i E. F. van Dishoeck. "Molecule formation in dust-poor irradiated jets". Astronomy & Astrophysics 636 (kwiecień 2020): A60. http://dx.doi.org/10.1051/0004-6361/201937383.

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Context. Recent ALMA observations suggest that the highest velocity part of molecular protostellar jets (≳80 km s−1) are launched from the dust-sublimation regions of the accretion disks (≲0.3 au). However, the formation and survival of molecules in inner protostellar disk winds, in the presence of a harsh far-ultraviolet radiation field and the absence of dust, remains unexplored. Aims. We aim to determine if simple molecules, such as H2, CO, SiO, and H2O, can be synthesized and spared in fast and collimated dust-free disk winds or if a fraction of dust is necessary to explain the observed molecular abundances. Methods. This work is based on a recent version of the Paris-Durham shock code designed to model irradiated environments. Fundamental properties of the dust-free chemistry are investigated from single point models. A laminar 1D disk wind model was then built using a parametric flow geometry. This model includes time-dependent chemistry and the attenuation of the radiation field by gas-phase photoprocesses. The influence of the mass-loss rate of the wind and of the fraction of dust on the synthesis of the molecules and on the attenuation of the radiation field is studied in detail. Results. We show that a small fraction of H2 (≤10−2), which primarily formed through the H− route, can efficiently initiate molecule synthesis, such as CO and SiO above TK ~ 800 K. We also propose new gas-phase formation routes of H2 that can operate in strong visible radiation fields, involving CH+ for instance. The attenuation of the radiation field by atomic species (e.g., C, Si, and S) proceeds through continuum self-shielding. This process ensures the efficient formation of CO, OH, SiO, and H2O through neutral–neutral reactions and the survival of these molecules. Class 0 dust-free winds with high mass-loss rates (Ṁw ≥ 2 × 10−6 M⊙ yr−1) are predicted to be rich in molecules if warm (TK ≥ 800 K). Interestingly, we also predict a steep decrease in the SiO-to-CO abundance ratio with the decline of mass-loss rate, from Class 0 to Class I protostars. The molecular content of disk winds is very sensitive to the presence of dust, and a mass-fraction of surviving dust as small as 10−5 significantly increases the H2O and SiO abundances. Conclusions. Chemistry of high velocity jets is a powerful tool to probe their content in dust and uncover their launching point. Models of internal shocks are required to fully exploit the current (sub)millimeter observations and prepare future JWST observations.

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Tan, Zhi Kai, Zhen Hua Xie, Hong Jie Wang, Bin Liu, Chun Yi Tong i Yong Jun Tan. "Jet Stabilities in the Electrospraying of Macro-Molecules Solutions for Controllable Micro-Printing". Advanced Materials Research 900 (luty 2014): 531–37. http://dx.doi.org/10.4028/www.scientific.net/amr.900.531.

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Electrospraying (ES) is of great interest in research for its finely controlled delivery of biomaterials. This study investigated mechanisms involved in the electrospraying of biological macro-molecules which may cause spraying instabilities. Hyaluronan (HA) solutions with concentrations ranging from 1 to 5 w/v % (w in g and v in 100 ml) were prepared for spraying trials using nozzles with a size of 30 μm. In electrifying HA solutions with a high molecular weight of 2.1 MDa, controllable jets can be achieved only at the lowest concentration of 1 w/v %. Generally, further use of a sonication method to reduce the molecular size, stable cone jets can be performed relatively easily than using HA solutions of higher concentrations. The improvement of spray stabilities can be attributed to the reduction in viscosity of the solutions after the sonication. Steady micro-sized jets were observed during the ES process and the jet size was found to increase with the increase of both the molecular size and the concentration. Both parameters can be directly ascribed to the rheological property of the solutions. Results show that a suitable viscosity is critically important in stabilizing the electrospray of macro-molecules. A concentration reduction of HA molecules also happens during electrospraying, which indicates that there is a partial reflection of macro-molecules inside the Taylor-cone with the fluid motions during the spraying process. This partial reflection process is affected by molecular sizes, solution concentrations and spraying time.

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Eislöffel, Jochen. "Molecular Hydrogen Emission in Embedded Flows". Symposium - International Astronomical Union 182 (1997): 93–102. http://dx.doi.org/10.1017/s007418090006157x.

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This overview of recent observations of molecular hydrogen (H2) in outflows from young stars discusses the morphology, the excitation and the kinematics of the H2 gas in these flows. A comparison between the H2 and CO outflows will lead us to the conclusion that highly-collimated jets may drive the latter. We also discuss the mechanisms which can entrain ambient molecular gas into the jet flow.

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Imai, Hiroshi, Tetsuo Sasao, Kumiko Obara, Toshihiro Omodaka i Philip J. Diamond. "A collimated molecular jet in W 43A traced by water maser emission". Symposium - International Astronomical Union 206 (2002): 80–83. http://dx.doi.org/10.1017/s0074180900222110.

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We present the spatial and velocity distributions of water masers in W 43A. Most of the maser features are spatially and kinematically collimated to a surprising extent. It is very likely that the jet in W 43A is predominantly composed of warm molecules traced by water maser emission. The position angle of the spatial collimation of the maser clusters is slightly different from the directions of both the cluster separation and the proper motions. We propose a model involving a precessing jet to explain the axis offsets. The discovery of a molecular jet with precession in W 43A provides important information on our understanding of the formation of collimated molecular jets and may provide clues on specific stages of stellar evolution.

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Mundt, Reinhard. "Jets From Young Stars". International Astronomical Union Colloquium 89 (1986): 6–9. http://dx.doi.org/10.1017/s0252921100085997.

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AbstractRecent optical observations have shown that many young stars are capable of generating highly-collimated bipolar flows. Such flows are evident from narrow emission-line jets extending over 0.01-1 pc and having opening angles of a few degrees. Their measured radial velocities reach values of up to 400 km/s. For most known jets the “driving stars” are T Tauri stars or IR-sources of low to moderate luminosity (1-100 L⊙) . The typical velocities, Mach numbers, particle densities, and mass fluxes of these jets are estimated to be 200-400 km/s, 10-40, 15-150 cm−3, and 10−10−10−7 M⊙/yr, respectively. The estimated mass fluxes and velocities are consistent with our present knowledge of T Tauri star wind properties.The emission-line spectra of the jets are the same as observed in Herbig-Haro (HH) objects. Furthermore, the brightest parts of some jets (hot spots) are known as HH objects, having often been discovered many years before their associated jet. Thus, both phenomena are highly related and in both cases the emission lines are very probably formed in the cooling regions of shock waves with velocities of 50-100 km/s. There are a variety of mechanisms, which can in principal excite internal (oblique) Shockwaves in these jets. Examples of likely excitation mechanisms are fluid dynamical instabilities or pressure gradients in the ambient medium.A model is proposed in which HH objects are representing the locations of the most strongly radiating (internal)shock waves in these jets. For those HH objects being located at the end of the jet the observational data strongly suggest that they are tracing the working surface of the jet. This idea is consistent with the observed proper motions of these HH objects, the typical densities near the edges of their associated molecular clouds, and with the jet parameter given above. For a more detailed discussion of these jets the reader is refered to the review articles listed below.

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Rozprawy doktorskie na temat "Molecular jets"

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Bence, Stephen John. "Stellar jets and molecular outflows". Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627089.

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Guzmán, Fernández Andrés Ernesto. "Ionized Jets and Molecular Outflows in High-Mass Young Stellar Objects". Tesis, Universidad de Chile, 2012. http://repositorio.uchile.cl/handle/2250/102759.

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Uno de los problemas claves en el estudio de la formación de estrellas es determinar si acaso el paradigma de formación de estrellas de baja masa, específicamente, contracción gravitacional y la posterior presencia de un disco de acreción y chorros altamente colimados, se extiende a las estrellas de alta masa. En esta tesis se lleva a cabo una búsqueda sistemática de chorros ionizados hacia objetos estelares jóvenes de alta masa. La presencia de estos chorros entrega evidencia que sostiene dos importantes nociones astrofísicas: que las estrellas de alta masa pasan por una fase de eyección chorros y acreción desde un disco, y que además estos chorros serían la fuente de energía de los flujos moleculares masivos. Para la búsqueda de chorros se utilizó interferometría en el radio continuo centimétrico. Como sub-producto de esta búsqueda, se presenta también una lista de objetos estelares jóvenes de alta masa candidatos a albergar un chorro ionizado. Para el estudio del gas molecular y los flujos bipolares se utilizan telescopios sub-milimétricos ubicados en el Norte Grande de Chile. Analizando la incidencia y las características de estos chorros y de los flujos moleculares asociados, se extraerán conclusiones respecto al proceso de formación de estrellas de alta masa, la pertinencia de los chorros en este proceso, y algunas características físicas de éstos.

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Davis, Christopher John. "The molecular structure of Herbig-Haro objects, outflows and jets from young stellar objects". Thesis, University of Edinburgh, 1992. http://hdl.handle.net/1842/27879.

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The observations discussed in this thesis are of regions of star-formation where outflow is believed to be occurring. Specifically, radio, millimeter/sub-millimeter and infrared observations are made to illustrate the molecular structure of outflows and related phenomena. CO J = 2-1 observations of the molecular outflow from the infrared reflection nebulae GGD27 IRS complement earlier CO J&61 1-0 observations and further allow us to revise previous estimates of the outflow mass and energetics. The mass derived here is comparable to mass estimates for other outflows from similarly luminous sources, though it is a factor of ~10 less than that derived from the earlier CO 1-0 observations. This difference is due to the choice of excitation temperature used in deriving the outflow mass; here combining CO 2-1 observations with the 1-0 studies allows us to calculate T_ex more precisely. I also show that the conical outflow overlaps the plain of the sky, and find that the observed molecular flow is not powerful enough to excite the associated HH nebulae HH80/81. Studies of the molecular environment around the HH objects HH1 and 2, and towards the optical jet/HH bow-shock system HH34 reveal the presence of dense, quiescent molecular material associated with all three HH objects. The presence of such stationary, molecular clumps, particularly evident in HH2 and HH34, does not support current popular HH models. Observations of these regions in a number of molecular species also show how contrasting and sometimes misleading observations in different molecular gas tracers can be: In HH2 peaks seen in NH_3 (,1) do not coincide with the well resolved clump observed in HCO^+ J = 3-2, whilst the C^18O J = 2-1 emission shows no clear peak at all. These contrasting morphologies are thought to be due to the differing excitation requirements of the observed lines. However, in HH34 chemical abundance variations are also significant: Towards the exciting source of the optical stellar jet and HH bow-shock, the NH_3 is underabundant. Indeed, in many other outflow sources, a similar NH_3 depletion is observed towards the central source. Instead, the NH_3 delineates a toroidal structure that encircles the central gas-density peak and the outflow source.

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Navea, Juan G. Manzanares Carlos E. "Studies on the application of laser photoionization in supersonic-jets for the generation of intense ionic clusters". Waco, Tex. : Baylor University, 2006. http://hdl.handle.net/2104/4878.

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Beuran, Florin. "Croissance de films de cuprates supraconducteurs par épitaxie par jets moléculaires". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2005. http://pastel.archives-ouvertes.fr/pastel-00644501.

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Ce travail concerne l'épitaxie par jets moléculaires de films de BiSrCaCuO. On y présente un dispositif de pilotage de la croissance grâce à la diffraction d'électrons rapides RHEED, comprenant également des logiciels d'analyse permettant de corréler l'évolution du diagramme RHEED, avec les propriétés physiques (composition, structure et morphologie, transport ...). Cette analyse, appliquée au cas de films appauvris en Bi, permet de les décrire comme une nanostructure d'intercroissance, en partie ordonnée suivant un modèle " mur de briques " où deux types de nanophases alternent en quinconce : Bi-2212 et Bi-2PRQ d'épaisseur double. Selon la composition moyenne des films, trois familles de nanophases 2PRQ sont identifiées, qui correspondent à des modèles structuraux spécifiques : stoechiométriques Bi-2267, riches en Sr Bi-2446, riches en Cu Bi-2429 comportant des plans Cu2O3 de type échelles. Les conditions physiques pour la synthèse de chaque famille nanostructurée sont décrites.

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Yung, Hong-kiu Bosco, i 容康喬. "VLBA observations and kinematic modelling of the high velocity molecular jets from the water fountain IRAS 18286-0959". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B45847848.

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Le, Thuy Thanh Giang. "Croissance de nanofils III-V par épitaxie par jets moléculaires". Phd thesis, Université de Grenoble, 2014. http://tel.archives-ouvertes.fr/tel-01067836.

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Ce travail a pour objectif la fabrication, en épitaxie par jets moléculaires, de nanofils coeurcoquilleà base de GaAs et AlGaAs déposés sur des substrats Si(111), en vue de réaliser desréseaux de fils pour de nouvelles cellules solaires, et pour des fils photoniques permettant uneapproche bottom-up d'émetteurs de photons uniques.La première partie de ce travail est une étude systématique des paramètres clés qui contrôlent lacroissance uni-dimensionnelle de fils GaAs élaborés par un mécanisme vapeur-liquide-solideauto-catalysé, à savoir le rapport des flux As/Ga, la température du substrat, et la vitesse decroissance.La seconde partie se concentre sur la croissance et la caractérisation de fils GaAs recouvertsd'une coquille d'alliages AlGaAs (35% Al) afin de s'affranchir des recombinaisons de surface.Ces coquillesde AlGaAs sont fabriquées en conditions riche-As (rapport As/Ga > 10) afin deconsommer les gouttes de catalyseur gallium et de promouvoir une croissance radiale (le taux decroissance maximal axial/radial est égal à 6). Diverses caractérisations optiques sont réalisées àbasse température sur ces ensembles de fils : cathodoluminescence, photoluminescence etspectroscopie résolue en temps. L'intensité de luminescence et la durée de vie des porteursaugmentent fortement avec la présence de la coquille : une épaisseur de 7 nm de cette dernièreest suffisante pour optimiser la passivation des nanofils et supprimer les recombinaisons liéesaux états de surface. Une fine couche extérieure de GaAs est nécessaire pour éviter touteoxydation de la coquille d'alliage AlGaAs.De plus, grâce à des mesures de CL résolues spatialement, les longueurs de diffusion desexcitons dans ces fils ont été obtenues, allant de 0.7 μm à 1.5 μm pour des épaisseurs decoquilles comprises entre 20 et 50 nm. Des valeurs plus petites sont mesurées pour des coquillesplus épaisses, ce qui tend à montrer l'introduction de défauts dans l'alliage qui pourraientlimiter la qualité de l'interface. Le décalage en énergie de l'émission fournit des informationssur la génération de contraintes dans ces fils coeur-coquille et sur le champ piézo-électrique quien découle.

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Fontaine, Christophe. "Hétéroépitaxie par jets moléculaires de semiconducteurs II-VI". Grenoble 1, 1986. http://www.theses.fr/1986GRE10062.

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Etude de l'heteroepitaxie de cdte, cd::(1-x)zn::(x)te et cd::(x)hg::(1-x)te sur cdznte, insb et gaas (001) et (111) et des differents parametres qui gouvernent la qualite cristalline. Il s'avere que la croissance (001) est meilleure que la croissance (111). L'interet d'une interface graduelle est demontre a fort desaccord de maille. A faible desaccord de mailles les contraintes dans les couches epitaxiques ont ete mesurees. Dans ces conditions experimentales, la relaxatioon des couches est gouvernee par un mecanisme de generation de dislocations et non par l'activation thermique des dislocations presentes. Les modeles existants ne permettent pas de decrire la relaxation dans les couches cdte. Presentation d'un modele qui rend compte des observations

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Fontaine, Chantal. "Heteroepitaxie par jets moeculaires : systeme (ca,sr)f::(2) - gaas". Toulouse 3, 1987. http://www.theses.fr/1987TOU30135.

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Dans la premiere partie du memoire sont etudies les mecanismes de formation de defauts pendant la croissance cristalline, les contraintes s'exercant sur les couches heteroepitaxiales, la possibilite de relaxation de ces contraintes par creation de defauts ainsi que les solutions pratiques envisagees pour eliminer ces defauts. Dans la seconde partie sont presentes et analyses les resultats experimentaux obtenus sur les structures (ca,sr)f::(2)/gaas et gaas/(ca,sr)f::(2) realisees par epitaxie par jets moleculaires. Sont consideres les proprietes des interfaces, les relations d'epitaxie, les mecanismes de croissance et les contraintes. Finalement, sont discutees les applications potentielles de ce type de structures et leur compatibilite avec les proprietes optiques et electriques des deux materiaux elabores

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Drabek-Maunder, Emily Rae. "A submillimetre study of nearby star formation using molecular line data". Thesis, University of Exeter, 2013. http://hdl.handle.net/10871/14587.

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This thesis primarily uses submillimetre molecular line data from HARP, a heterodyne array on the James Clerk Maxwell Telescope (JCMT), to further investigate star formation in the Ophiuchus L1688 cloud. HARP was used to observe CO J = 3-2 isotopologues: 12CO, 13CO and C18O; and the dense gas tracer HCO+ J = 4-3. A method for calculating molecular line contamination in the SCUBA-2 450 and 850 μm dust continuum data was developed, which can be used to convert 12CO J =6-5and J =3-2 maps of integrated intensity (K km s−1) to molecular line flux (mJy beam−1) contaminating the continuum emission. Using HARP maps of 12CO J = 3-2, I quantified the amount of molecular line contamination found in the SCUBA-2 850 μm maps of three different regions, including NGC 1333 of Perseus and NGC 2071 and NGC 2024 of Orion B. Regions with ‘significant’ (i.e. > 20%) molecular line contamination correspond to molecular outflows. This method is now being used to remove molecular line contamination from regions with both SCUBA-2 dust continuum and HARP 12CO map coverage in the Gould Belt Legacy Survey (GBS). The Ophiuchus L1688 cloud was observed in all three CO J = 3-2 isotopologues. I carried out a molecular outflow analysis in the region on a list of 30 sources from the Spitzer ‘c2d’ survey [Evans et al., 2009]. Out of the 30 sources, 8 had confirmed bipolar outflows, 20 sources had ‘confused’ outflow detections and 2 sources did not have outflow detections. The Ophiuchus cloud was found to be gravitationally bound with the turbulent kinetic energy a factor of 7 lower than the gravitational binding energy. The high-velocity outflowing gas was found to be only 21% of the turbulence in the cloud, suggesting outflows are significant but not the dominant source of turbulence in the region. Other factors were found to influence the global high-velocity outflowing gas in addition to molecular outflows, including hot dust from nearby B-type stars, outflow remnants from less embedded sources and stellar winds from the Upper Scorpius OB association. To trace high density gas in the Ophiuchus L1688 cloud, HCO+ J = 4-3 was observed to further investigate the relationship between high column density and high density in the molecular cloud. Non-LTE codes RADEX and TORUS were used to develop density models corresponding to the HCO+ emission. The models involved both constant density and peaked density profiles. RADEX [van der Tak et al., 2007] models used a constant density model along the line-of-sight and indicated the HCO+ traced densities that were predominantly subthermally excited with den- sities ranging from 10^3–10^5 cm^−3. Line-of-sight estimates ranged from several parsecs to 90 pc, which was unrealistic for the Ophiuchus cloud. This lead to the implementation of peaked density profiles using the TORUS non-LTE radiative transfer code. Initial models used a ‘triangle’ density profile and a more complicated log-normal density probability density function (PDF) profile was subsequently implemented. Peaked density models were relatively successful at fitting the HCO+ data. Triangle models had density fits ranging from 0.2–2.0×10^6 cm^−3 and 0.1–0.3×10^6 cm^−3 for the 0.2 and 0.3 pc cloud length models re- spectively. Log-normal density models with constant-σ had peak density ranges from 0.2–1.0 ×10^5 cm^−3 and 0.6–2.0×10^5 cm^−3 for 0.2 and 0.3 pc models respectively. Similarly, log-normal models with varying-σ had lower and upper density limits corresponding to the range of FWHM velocities. Densities (lower and upper limits) ranged from 0.1–1.0 ×10^6 and 0.5–3.0 ×10^5 cm^-3 for the 0.2 and 0.3 pc models respectively. The result of the HCO+ density modelling indicated the distributions of starless, prestellar and protostellar cores do not have a preference for higher densities with respect to the rest of the cloud. This is contrary to past research suggesting the probability of finding a submillimetre core steeply rises as a function of column density (i.e. density; Belloche et al. 2011; Hatchell et al. 2005). Since the majority of sources are less embedded (i.e Class II/III), it is possible the evolutionary state of Ophiuchus is the main reason the small sample of Class 0/I protostars do not appear to have a preference for higher densities in the cloud.

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Książki na temat "Molecular jets"

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Fritsche, Bent. Untersuchung der Stromung in einem Freistrahl-Kernfreistrahl-System zur Erzeugung intensiver Molekularstrahlen. Koln, Germany: DLR, 1994.

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Giuseppe, Tomassetti, red. Introduction to molecular beams gas dynamics. London: Imperial College Press, 2005.

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Hollas, J. M. Jet Spectroscopy and Molecular Dynamics. Dordrecht: Springer Netherlands, 1995.

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Hollas, J. M., i D. Phillips, red. Jet Spectroscopy and Molecular Dynamics. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-1314-4.

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Liang, Wenlie. Millimeter wave spectroscopy of bulk gases and supersonic jet molecular beams. Manchester: University of Manchester, 1991.

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Nakhate, S. G. Supersonic pulsed free-jet of atoms and molecules of refractory metals: Laser induced fluorescence spectroscopic studies on zirconium atoms and zirconium oxide molecules. Mumbai: Bhabha Atomic Research Centre, 2004.

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Michael, Hollas J., i Phillips D, red. Jet spectroscopy and molecular dynamics. London: Blackie Academic & Professional, 1995.

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Tomassetti, Giuseppe, i Giovanni Sanna. Introduction to Molecular Beam Gas Dynamics. Imperial College Press, 2005.

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United States. National Aeronautics and Space Administration., red. Instantaneous 2D velocity and temperatire measurements in high speed flows based on spectrally resolved molecular Rayleigh scattering. [Washington, DC]: National Aeronautics and Space Administration, 1995.

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Lyndon B. Johnson Space Center., red. The identification of excited species in arc jet flow. Houston, Tex: National Aeronautics and Space Administration, Lyndon B. Johnson Space Center, 1987.

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Więcej źródeł

Części książek na temat "Molecular jets"

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Bachiller, Rafael. "Molecular Outflows: Observations". W Protostellar Jets in Context, 381–93. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-00576-3_46.

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Greaves, J. S. "Molecular Jets in OMC1-S". W Astrophysics and Space Science Library, 77–80. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1924-5_15.

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Downes, Turlough P. "Driving Mechanisms for Molecular Outflows". W Protostellar Jets in Context, 395–404. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-00576-3_47.

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Flower, David. "Flows in Molecular Media". W Jets from Young Stars IV, 161–94. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-02289-0_5.

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Olberg, M. "Optical Jets Associated with Molecular Outflows". W Astrophysics and Space Science Library, 227–28. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1924-5_43.

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O’Sullivan, Jamie, i Max Camenzind. "Molecular Cooling in Large Scale Simulations of Protostellar Jets". W Protostellar Jets in Context, 453–58. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-00576-3_54.

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Stanke, Thomas. "Observations of Molecular Jets in Orion a". W Jets in Young Stellar Objects, 149–60. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-007-0999-7_24.

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Agra-Amboage, Vanessa, Catherine Dougados i Sylvie Cabrit. "0.15″ Study of the Atomic and Molecular Jets in DG Tau". W Protostellar Jets in Context, 477–83. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-00576-3_58.

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Padman, Rachael, i John S. Richer. "Interactions between molecular outflows and optical jets". W Kinematics and Dynamics of Diffuse Astrophysical Media, 129–34. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-0926-0_20.

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Hollas, J. M. "Large Amplitude Vibrations in Electronic Spectra in Supersonic Jets". W Low Temperature Molecular Spectroscopy, 311–50. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-0281-7_13.

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Streszczenia konferencji na temat "Molecular jets"

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SEGAL, CORIN, JOHN ABBITT i BRUCE CARROLL. "Molecular mixing of jets in supersonic flow". W 29th Joint Propulsion Conference and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1993. http://dx.doi.org/10.2514/6.1993-2021.

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Bocklitz, Sebastian, Martin Suhm, Timothy Zwier i Daniel Hewett. "PROBING THE CONFORMATIONAL LANDSCAPE OF POLYETHER BUILDING BLOCKS IN SUPERSONIC JETS". W 71st International Symposium on Molecular Spectroscopy. Urbana, Illinois: University of Illinois at Urbana-Champaign, 2016. http://dx.doi.org/10.15278/isms.2016.mj07.

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King, G., R. Lucht, J. Dutton, G. King, R. Lucht i J. Dutton. "Instantaneous dual-tracer PLIF measurements of molecular mixing in axisymmetric jets". W 35th Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1997. http://dx.doi.org/10.2514/6.1997-152.

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Whetten, Robert L. "Laser Excitation Dynamics Of Atomic And Molecular Clusters In Free Jets". W O-E/LASE'86 Symp (January 1986, Los Angeles), redaktor Mostafa A. El-Sayed. SPIE, 1986. http://dx.doi.org/10.1117/12.961129.

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Frank, Adam. "YSO jets and molecular outflows: Tracing the history of star formation". W Accretion processes in astrophysical systems: Some like it hot! - eigth astrophysics conference. AIP, 1998. http://dx.doi.org/10.1063/1.55880.

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Popov, Ivan I., i Vitaly V. Samartsev. "Photon echo as a method of a spectroscopy of molecular iodine vapors in cooling supersonic molecular jets". W SPIE Proceedings, redaktor Vitaly V. Samartsev. SPIE, 2004. http://dx.doi.org/10.1117/12.562272.

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Sosnin, Eduard A., Maria Didenko, Victor Panarin, Victor Skakun, Victor F. Tarasenko, Dongping P. Liu i Ying Song. "NOx formation in apokamp-type atmospheric pressure plasma jets in air initiated by a pulse-repetitive discharge". W XIII International Conference on Atomic and Molecular Pulsed Lasers, redaktorzy Andrei M. Kabanov i Victor F. Tarasenko. SPIE, 2018. http://dx.doi.org/10.1117/12.2301027.

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Panda, J., R. G. Seasholtz, K. A. Elam i A. F. Mielke. "Time-Averaged Velocity, Temperature and Density Surveys of Supersonic Free Jets". W ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56856.

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Streszczenie:

A spectrally resolved molecular Rayleigh scattering technique was used to simultaneously measure axial component of velocity U, static temperature T, and density ρ in unheated free jets at Mach numbers Mj = 0.6, 0.95, 1.4 and 1.8. The latter two conditions were achieved using contoured convergent-divergent nozzles. A narrow line-width continuous wave laser was passed through the jet plumes and molecular scattered light from a small region on the beam was collected and analyzed using a Fabry-Perot interferometer. The optical spectrum analysis provided measures of velocity and static temperature. The local air density at the probe volume was determined by monitoring the intensity variation of the scattered light using photomultiplier tubes. The Fabry-Perot interferometer was operated in the imaging mode, whereby the fringe formed at the image plane was captured by a cooled CCD camera. Special attention was given to remove dust particles from the plume and to provide adequate vibration isolation to the optical components. The velocity profiles from various operating conditions were compared with that measured by a Pitot tube. An excellent comparison within 5m/s demonstrated the maturity of the technique. Temperature was measured least accurately, within 10K, while density was measured within 1% uncertainty. The survey data consisted of centerline variations and radial profiles of time-averaged U, T and ρ. The static temperature and density values were used to determine static pressure variations inside the jet. The data provided a comparative study of jet growth rates with increasing Mach number. The current work is part of a data-base development project for Computational Fluid Dynamics and Aeroacoustics codes that endeavor to predict noise characteristics of high speed jets. A limited amount of far field noise spectra from the same jets are also presented. Finally, a direct experimental validation was obtained for the Crocco-Busemann equation which is commonly used to predict temperature and density profiles from known velocity profiles. Data presented in this paper are available in ASCII format upon request.

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Zierhut, J., P. Haslbeck, K. D. Landes, G. Barbezat, M. Muller i M. Schutz. "Triplex – An Innovative Three-Cathode Plasma Torch". W ITSC 1998, redaktor Christian Coddet. ASM International, 1998. http://dx.doi.org/10.31399/asm.cp.itsc1998p1375.

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Abstract Present standard d.c. plasma torches are characterized by the combination of a single rod-shaped cathode and a conical one-piece anode. Mixtures of inert gases and molecular gases are used for plasma spraying of high melting powders. By adding the molecular gases high enthalpy plasma jets are generated, but simultaneously the well-known art root fluctuations cause an inhomogeneous treatment of the injected powder. The innovative plasma torch system TRIPLEX is characterized by a long nozzle and by three parallel cathodes. The nozzle consists of several rings all electrically insulated except for the last one which operates as an anode. By increasing the number of rings the three arts between the cathode tips and the anode ring can be lengthened. This leads to a higher art voltage and therefore to a higher enthalpy in the plasma jet. No molecular gases have to be used and are root fluctuations are prevented. The result is a uniform treatment of the injected powder. Using optical and electrical diagnostics the TRIPLEX torch ist compared to a typical conventional plasma torch. High spray rates and deposition efficiencies show the good performance of TRIPLEX.

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Ito, Shingo, Hiroaki Yamamoto, Shinji Ishigami, Akiko Kawamura, Norikazu Mizuno, Toshikazu Onishi, Yasuo Fukui i in. "Molecular Clouds Possibly Associated with the Jets from a Compact Star of L = 348.5 degrees and SS433; “Galactic vapor trail” as a probe of black hole candidates". W ASTROPHYSICS OF COMPACT OBJECTS: International Conference on Astrophysics of Compact Objects. AIP, 2008. http://dx.doi.org/10.1063/1.2840424.

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Raporty organizacyjne na temat "Molecular jets"

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Bernstein, Elliot R. Molecular Jet Studies of vdW Clusters and Solvation. Fort Belvoir, VA: Defense Technical Information Center, październik 1991. http://dx.doi.org/10.21236/ada242866.

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Seeman, Jeffrey I., Henry V. Secor, P. J. Breen, V. H. Grassian i E. R. Bernstein. A Study of Non-Rigid Aromatic Molecules by Supersonic Molecular Jet Spectroscopy: Observation and Spectroscopic Analysis of the Stable Conformations of Various Alkylbenzenes. Fort Belvoir, VA: Defense Technical Information Center, lipiec 1988. http://dx.doi.org/10.21236/ada199409.

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Busarow, K. L. Tunable far infrared laser spectroscopy of Van der Waals molecules in a planar supersonic jet expansion. Office of Scientific and Technical Information (OSTI), grudzień 1990. http://dx.doi.org/10.2172/5610416.

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Field, Robert W. Metastable Electronically Excited Atoms and Molecules: Excitation Transfer in Slow Collisions, Probed by Means of a Counter-Rotating Supersonic Jet. Fort Belvoir, VA: Defense Technical Information Center, sierpień 2012. http://dx.doi.org/10.21236/ada582459.

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