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Articles de revues sur le sujet "Chamba Masks"
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Hak, Elżbieta. « Stereotypes and masks – a figure of “Polish Boor” on the example of Jerzy Duda-Gracz ». Ziemia Częstochowska 43 (2017) : 307–13. http://dx.doi.org/10.16926/zc.2017.43.18.
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Achint, Ramandeep, et Devinder Singh. « First record of the phoretic association between Pediculaster sp. (Pygmephoridae) mites and Musca crassirostris (Muscidae) flies in India ». Journal of Threatened Taxa 16, no 4 (26 avril 2024) : 25103–6. http://dx.doi.org/10.11609/jott.8738.16.4.25103-25106.
Texte intégralRésumé :
This article reports for the first time a phoretic pygmephorid mite on a muscid fly from India, with pygmephorid mites classified under the order Prostigmata and the family Pygmephoridae. The mites, identified as species of the genus Pediculaster belonging to the family Pygmephoridae, were collected in July 2019 from Khajjiar town, located in the Chamba district of Himachal Pradesh, India. The flies, identified as Musca crassirostris belonging to the family Muscidae, were also noted. While this study marks a significant step in Indian research, further investigation is warranted to comprehensively compile data on the species accuracy of mites and their habitat preferences.
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Moncel, M. H. « Marks, A.E., Chabai, V.P., (Éds), 1998. The middle Paleolithic of western Crimea. » L'Anthropologie 107, no 2 (avril 2003) : 310–11. http://dx.doi.org/10.1016/s0003-5521(03)00013-x.
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Lewis, Jonathan. « Identity and Identification in Azouz Begag’s Le Gone du Chaâba and Béni ou le paradis privé ». FORUM : University of Edinburgh Postgraduate Journal of Culture & ; the Arts, no 11 (12 décembre 2010) : 1–14. http://dx.doi.org/10.2218/forum.11.656.
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"Man is human only to the extent to which he tries to impose his existence on another man in order to be recognised by him [...] It is on that other being, on recognition by that other being, that his own human worth and reality depend." (Fanon 216-17)The dependence of one’s “human worth and reality” on mutual recognition, highlighted by Frantz Fanon in his seminal text Black Skin White Masks, first published in 1952, plays a central role in the construction of identity in Azouz Begag’s first two novels, Le Gone du Chaâba and Béni ou le paradis privé, published in 1986 and 1989 respectively. Using contemporary post-colonial criticism to carry out a close reading of these two texts, this article will take into account the memory of the Algerian War of Independence (1954-1962), which marked Algeria’s independence from French colonial rule, and its connection to France’s current attitude towards ethnic difference. Subsequently, the effect of these factors on considerations of contemporary Franco-Algerian selfhood will be examined, and the analysis will go on to demonstrate how an Algerian presence in France, forty-eight years after the end of the Algerian War, continues to come into conflict with the French Republic’s constitutional definition of nationhood, which favours unity of the nation by uniformity rather than an embracing of multiple identities.
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Figueiredo, Ruy Cézar Campos. « Músculos, Exú e axé e no realismo performativo de Esse amor que nos consome ». Significação : Revista de Cultura Audiovisual 47, no 54 (9 juillet 2020) : 141–58. http://dx.doi.org/10.11606/issn.2316-7114.sig.2020.160170.
Texte intégralRésumé :
Analisam-se cenas e se destacam eventos do filme Esse amor que nos consome (2012), de Allan Ribeiro, a partir de uma abordagem fenomenológica e tátil dos estudos fílmicos presente em autoras como Laura Marks, Vivian Sobchack e Jennifer Barker. Tal abordagem chama atenção para a corporificação, que no filme aqui analisado ganha características peculiares do modo afro-brasileiro de se relacionar com o corpo, considerando outras ontologias no relacionamento com a realidade e sua performance cinematográfica.
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-, Sabyasachi Bose. « The Influence of Western Fantasy Fiction on Contemporary Bengali OTT and TV Series ». International Journal For Multidisciplinary Research 5, no 6 (22 novembre 2023). http://dx.doi.org/10.36948/ijfmr.2023.v05i06.9206.
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The publication of the Lord of the Rings trilogy marks a significant watershed moment in the literary history of the twentieth century. After the publication of this seminal text, it was “translated into numerous languages”(Manlove 156) and it also began to weave its influence into the various literary and cultural traditions of the world. Though the state of West Bengal possessed a powerful and rich literary and cultural background, in terms of supernatural or fantastic literature, the Bengali cultural field also started to take the colour of Tolkien’s magnum opus. Subsequently, the Harry Potter phenomenon in the 1990s, and the widely watched Peter Jackson film adaptations of the Lord of the Rings, added to the popularity of Western fantasy in West Bengal. This can be traced in a number of articles in Bengali magazines, journals, and blogs, such as “Angti Niye Abar Lorai,” “Dorja Jure Bisal Sap Er Murti! Khoj Millo,” which reveal the investment of Bengali audiences in the genre. Gradually, as this paper will argue in some detail, some of the newly emergent Bengali OTT and TV series, coming out in the post 2010s - were also coloured by the cultural expansion of Western fantasy. This paper will particularly demonstrate the influence of Western fantasy on Bengali OTT and TV Series with a special emphasis on the features of Western fantasy like the evocation of wonder through specific devices, mythopoeic tendencies, the dynamics of wish fulfilment, and the like. Side by side, the resemblance of scenes, actions, and ideas of the Lord of the Rings trilogy and the Harry Potter series in Bengali OTT and TV Series will also be depicted in this paper. The primary texts that will be studied, include one web series and two serials: Rudrabinar Obhishaap, Kiranmala, and Saat Bhai Champa.
Thèses sur le sujet "Chamba Masks"
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Sanchez, Erin. « Filtration Efficiency of Surgical Masks ». Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1760.
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Surgical masks are intended to be used to prevent transmission of disease from a health care worker to a patient. Often times, they are relied upon by health care workers for their own protection. In light of recent developments regarding preparation for health care worker response to global infectious diseases such as H1N1 Influenza, health care workers may experience a false sense of security when wearing surgical masks. The goal of this study was to evaluate the filtration efficiency of a double strap tie-on surgical mask. The manufacturer asserts a >95% efficiency with a 0.1 um challenge aerosol under FDA testing procedures. The NIOSH Title 42 CFR Part 84 certification criteria call for testing at a rate of 85 lpm representing a human moderate to heavy work load breathing rate. Three sizes of monodispersed aerosols (polystyrene latex beads: 0.5 um, 1.0 um, 2.0 um) were used.
The specific aims were to measure the collection efficiencies of this mask for the various particle sizes. Two tests were performed. In the first, masks were affixed to a dummy head and the edges of the mask were not sealed. In the second, the edges of the masks were sealed to the head using silicone sealant, so all penetration was through the filtering material of the mask. Differences in upstream and downstream particle concentrations were measured. Thus, penetration by leakage around the mask and through the filtering material was measured. The experimental set up involved passing the aerosol from the nebulizer through a diffusion dryer and Kr-85 charge equilibrator ensuring a dry charge neutralized aerosol cloud for detection by a LASAIR particle counter. The analysis revealed that the filtration efficiency for 0.5 um particles ranged from 3% to 43% for the unsealed masks and 42% to 51% for the sealed. For 1.0 um particles, the efficiency was 58% to 75% for unsealed and 71% to 84% for sealed masks. For 2.0 um, the efficiency was 58% to 79% for unsealed masks and 69% to 85% for the sealed masks. The data were statistically significant and indicated that surgical masks were associated with very low filtration efficiency. This suggests that they may be inadequate against airborne viruses and bacteria.
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Ozimek, Constance. « Mass Cycling through Crustal Magma Chambers and the Influence of Thermo-Mechanical State on Magma Compositions through Time ». Thesis, University of Oregon, 2018. http://hdl.handle.net/1794/23153.
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Magma chambers are a fundamental component of crustal magma transport modulating erupted volumes, compositions, and timing of eruptions. However, we understand little about how eruption episodicity relates to magma chamber evolution. A sizable amount of research has been done on the thermo-mechanical and chemical evolution of a chamber, but little has been done in combining the two. The many influences on composition make inference of crustal processes from erupted compositions dicult, but there are patterns of eruptive evolution in well- characterized systems that suggest something systematic is occurring.
We have developed a coupled thermo-mechanical-chemical model in order
to characterize melt evolution through cycles of chamber filling, rupture, and drainage in a thermally evolving, viscoelastic crust. We consider a deeply seated oblate spheroidal chamber, calculating pressure, temperature, volume, elemental concentration, partitioning between crystals and melt, and crustal temperature through time. We characterize the time dependence of chamber failure, thermal longevity, and melt elemental concentrations on mechanical parameters and influx rates, exploring the dependence on depth, primary and crustal compositions. These results should be important for constraining physical controls on eruption episodicity and predictions of instability at magmatic centers.
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Thomas, Zachariah. « Seeing a Tree for the Forest ». Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1554911121221355.
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Guénaut, Céline. « Optimized ion trapping of exotic nuclides for mass measurements in the N=40 (magic?) region ». Paris 11, 2005. http://www.theses.fr/2005PA112073.
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Les nombres magiques ou fermetures de couche sont une des caractéristiques importantes de la structure nucléaire, mais qui sont modifiés loin de la vallée de stabilité. La détermination de l'énergie de liaison, via des mesures de masse sur les noyaux exotiques, représente un des plus grands challenge dans l'étude de la structure nucléaire à cause de la précision importante qui est nécessaire, et du faible taux de production, ainsi que les courtes durées de vie. Afin de résoudre le problème, deux spectromètres de masse ISOLTRAP et MISTRAL peuvent être utilisés, tous les deux situés à ISOLDE/CERN (Genève). MISTRAL est un spectromètre de masse à transmission pour les noyaux de courtes durées de vie, et ISOLTRAP est un spectromètre de masse basé sur l'utilisation de pièges de Penning, qui effectue des mesures de masses de haute précision. Cette thèse décrit les techniques pour repousser les limites de ces deux instruments complémentaires: un système de refroidissement de faisceau pour améliorer la sensibilité de MISTRAL et une procédure d'optimisation pour améliorer la définition des champs de piégeage d'ISOLTRAP. Des mesures très précises ont été effectuées avec ISOLTRAP afin d'augmenter le nombre de noyaux très bien connus dans la table de masse, et afin d'examiner le cas de deux nouveauxnombres magiques N = 32 et N = 40. Les résultats montrent un surplus d'énergie de liaison pour le 56Cr32 dû à la présence d'une probable déformation. Pour le 68Ni40, il n'y a pas d'effet de liaison supplémentaire bien qu'un faible effet apparaisse, peut-être dû à une compétition avec la demi-couche à N = 39Magic numbers or shell closures, are an important feature of nuclear structure, but now found to be modified far from stability. Determination of the nuclear binding energy via mass measurements of exotic nuclides represents one of the greatest challenges in the study of nuclear structure due to the high precision required and the low production rates and short half-lives. To solve the problem, the complementary spectrometers MISTRALand ISOLTRAP may be used, both located at ISOLDE/CERN (Geneva). MISTRAL is a transmission mass spectrometer for very short-lived nuclides, and ISOLTRAP a Penningtrap mass spectrometer providing exceptional precision. This thesis describes improvements in the limitations of these complementary instruments: a beam cooler to increase the sensitivity of MISTRAL and an optimization procedure to improve the definition ofthe ISOLTRAP trapping fields. High-precision mass measurements were performed at ISOLTRAP to extend the backbone of well-known nuclides in the mass table, and to finely examine the case for new magic numbers N = 32 and 40. The results illustrate a subtle effect of extra binding energy for 56Cr32 in the presence of a probable deformation. Practically no additional binding is found for 68Ni40 though a small effect is visible, perhaps in conjunction with a competitive mid-shell effect at N = 39
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Erupe, Mark E. « Sources and Source Processes of Organic Nitrogen Aerosols in the Atmosphere ». DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/196.
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The research in this dissertation explored the sources and chemistry of organic nitrogen aerosols in the atmosphere. Two approaches were employed: field measurements and laboratory experiments. In order to characterize atmospheric aerosol, two ambient studies were conducted in Cache Valley in Northern Utah during strong winter inversions of 2004 and 2005. The economy of this region is heavily dependent on agriculture. There is also a fast growing urban population. Urban and agricultural emissions, aided by the valley geography and meteorology, led to high concentrations of fine particles that often exceeded the national ambient air quality standards. Aerosol composition was dominated by ammonium nitrate and organic species. Mass spectra from an aerosol mass spectrometer revealed that the organic ion peaks were consistent with reduced organic nitrogen compounds, typically associated with animal husbandry practices. Although no direct source characterization studies have been undertaken in Cache Valley with an aerosol mass spectrometer, spectra from a study at a swine facility in Ames, Iowa, did not show any evidence of reduced organic nitrogen species. This, combined with temporal and diurnal characteristics of organic aerosol peaks, was a pointer that the organic nitrogen species in Cache Valley likely formed from secondary chemistry. Application of multivariate statistical analyses to the organic aerosol spectra further supported this hypothesis. To quantify organic nitrogen signals observed in ambient studies as well as understand formation chemistry, three categories of laboratory experiments were performed. These were calibration experiments, smog chamber studies, and an analytical method development. Laboratory calibration experiments using standard calibrants indicated that quantifying the signals from organic nitrogen species was dependent on whether they formed through acid-base chemistry or via secondary organic aerosol pathway. Results from smog chamber reactions of amines with ozone, nitrogen oxides, nitrate radical, and nitric acid showed that the secondary organic aerosol pathway was more plausible than acid-base chemistry, thus making the contribution of the organic nitrogen species to the total aerosol mass in Cache Valley significant. Gas phase and aerosol products formed from the smog chamber reactions were identified and used to devise reaction mechanisms. Finally, an ion chromatographic method for detecting and quantifying some key organic nitrogen species in aerosol was developed and tested.
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Hudjetz, Stefan. « Experimental investigation of heat exchange between thermal mass and room environments ». Thesis, De Montfort University, 2012. http://hdl.handle.net/2086/9021.
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The different technologies of passive cooling concepts have to rely on a good thermal coupling between a building's thermal mass and indoor air. In many cases, the ceiling is the only surface remaining for a good coupling. Further research is necessary to investigate discrepancies between existing correlations. Therefore, the overall aim of the work described in this thesis is the investigation of heat transfer at a heated ceiling in an experimental chamber. Acoustic baffles obstruct the surface of the ceiling and impede heat transfer. However, there is nearly no published data about the effect of such baffles on heat transfer. Available results from simulations should be verified with an experimental investigation. Consequently, one of the primary aims of this work was to experimentally determine the influence of such acoustic baffles. A suitable experimental chamber has been built at Biberach University of Applied Sciences. The thesis describes the experimental chamber, the experimental programme as well as results from five different test series. With a value of ±0.1Wm⁻²K⁻¹ for larger temperature differences, uncertainty in resulting convective heat transfer coefficients for natural convection is comparable to that of results from an existing recent experimental work often recommended for use. Additionally, total heat transfer (by convection and radiation) results are presented. Results are given for natural, forced and mixed convection conditions at an unobstructed heated ceiling. Furthermore, results for acoustic baffles in both an unventilated and a ventilated chamber are shown. Natural convection results show a very good agreement with existing correlations. Under mixed convection conditions, convective heat transfer at an unobstructed ceiling decreases to the limiting case described by natural convection. Installation of acoustic baffles leads to a reduction in total heat transfer (convection and radiation) between 20% and 30% when compared to the case of an unobstructed ceiling.
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Osuagwu, Chiemeriwo Godday. « Investigation of volatile organic compounds from diesel engine emissions using H3O+ chemical ionisation mass spectrometry (H3O+-CIMS) ». Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/205507/1/Chiemeriwo_Osuagwu_Thesis.pdf.
Texte intégralRésumé :
Volatile organic compounds (VOCs) are organic compounds which exist in the gas phase at room temperature and atmospheric pressure. The lifespan of VOCs in the Earth's atmosphere ranges from a few minutes to months. Many VOCs are dangerous to human health and can undergo oxidation mediated aggregation to form secondary organic aerosols which are equally detrimental to human health. VOCs come from biogenic and anthropogenic sources, however, in cities, anthropogenic sources are dominant. A significant portion of these anthropogenic VOCs are coming from diesel vehicle emissions. Chemical composition of VOCs from diesel exhaust is complex and varies with the engine technology, driving conditions and fuel used.
Previously, VOCs have been measured using offline methods which required sample collection over a period (making it difficult to capture their temporal variability) and sample preparation (making the whole process time-consuming). The development of online mass spectrometrybased measurement techniques enabled monitoring VOCs in real time. Real time measurement of VOCs from the atmosphere is based on chemical ionisation mass spectrometry with hydronium ions as reagent ions. This was because hydronium ion allows the instrument to detect compounds that have proton affinity (PA) higher than that of water. Normal air components like N2 and O2 all have PA lower than water, however most of the saturated and unsaturated volatile organic compounds emitted from diesel exhaust have PA higher than water. The most commonly used instruments for atmospheric VOC measurement are Proton Transfer Reaction-Mass Spectrometer (quadrupole and Time of Flight), Selective Ion Flow Tube-Mass Spectrometer. The Aerodyne Chemical Ionisation Mass Spectrometer (CIMS) is a more recent instrument that allows the use of different reagent ions including hydronium ion H3O+. While both PTR-MS and SIFT-MS ionise samples at relatively low pressure (1-2 mbar) and their ionisation chambers been extensively studied, ion-Molecule Reaction (IMR) chamber in H3O+-CIMS operates at substantially higher pressure (~100 mbar) and, therefore, reagent ion distribution and ionisation chemistry are likely to be significantly different from the ones in PTR-MS and SIFT-MS. However, performance of the H3O+-CIMS has not been characterised in detail yet nor has this instrument been applied to investigate VOCs coming from diesel exhaust. This study is, therefore, aimed at characterising the performance of Aerodyne TOF-CIMS with H3O+ as reagent ions, herein referred to as H3O+-CIMS and later using the same for characterisation of diesel exhaust VOCs.
In characterising the H3O+-CIMS, the influence of the pressure inside the IMR chamber and SSQ (small sequential quadrupole) chamber on the intensity of reagent ions was explored. It was found that the optimum pressures for IMR and SSQ were ≥ 160 mbar and ≥ 2.3 mbar respectively. Exploration of radio frequency (RF) voltages of quadrupole ion guides inside the atmospheric pressure interface showed that 200V for the SSQ and 350V for the big sequential quadrupole (BSQ) are the optimum RF voltages for obtaining a maximum reagent ion signal intensity. The sensitivity of the instrument towards some common VOCs was determined using a custom-made VOC mixture. It was found that H3O+-CIMS was more sensitive to oxygenated VOCs compared to non-oxygenated VOCs. The sensitivity to oxygenated VOCs was comparable to PTR-MS and SIFT-MS while it was lower for non-oxygenated VOCs. It was also observed that relative humidity of the incoming air influences VOCs signal intensity with different compounds showing different RH dependence. Hydrate formation was explored as PTR-MS and SIFT-MS have both shown the formation of hydrate with increase in humidity.
In dry conditions with RH of 5%, hydrates were not formed for both non-oxygenated and oxygenated VOCs (NO-VOCs and O-VOCs respectively) except for acetonitrile with hydrate composition of ~7 – 25%. However, as RH increased to ~90%, hydrate composition was 10% 60% for NO-VOCs and ~ 3% to 4% for oxygenated VOCs. The instrument was tuned using 2 different tuning approaches - one aimed at maximising m/z 19 signal (H3O+) relative to the m/z 37 signal (H5O2 +) which maximises ion declustering and the other aimed at maximising m/z 37 signal (H5O2 +) relative to m/z 19 signal (H3O+) which minimises ion declustering. It was found that reagent ions and VOC signals were the highest with m/z 19 tuning approach.
After characterisation, the H3O+-CIMS was used to investigate VOCs from diesel exhaust. A total of 256 peaks were identified within a m/z range 15Th – 200Th, could not go beyond m/z 200 because peak resolution becomes very difficult beyond this point. 179 VOCs remained after the background had been subtracted, 44 of these VOCs were non-oxygenated hydrocarbon species, 79 were oxygenated species, 50 were nitrogen containing species and 9 were sulphur containing species.
VOC emissions from 3 diesel engines (Perkins, Kubota and Cummins) running on neat diesel fuel were compared. Cummins engine was found to emit the least number of VOCs in m/z 15 – 200 range which might be because it uses a common rail injection system unlike the other two engines, which utilise direct injection. When VOC emissions from neat diesel (D100) were compared with neat biodiesel (B100) using 3 diesel engines, benzene, toluene and xylene emissions were higher in B100 compared to D100 in all the engines. Similar trend was observed for CH5O+, C2H5O+, C4H5O+ and C5H9O+. This may be due to higher oxygen content in biodiesel compared to diesel fuel. However, a set of measurements was conducted where oxygen content of the fuel was varied by the use of biodiesel blends and it was shown that increasing the oxygen content of the fuel does not necessarily translate to increase in emissions of oxygenated VOCs. The role of oxygen content in the fuel was found to be compound dependent instead. It was also found that benzene, toluene and xylene emissions generally decreased with increase in oxygen content.
The contribution of this study to knowledge is that H3O+ -CIMS with IMR inlet is a useful tool in analysing VOCs emitted from diesel exhaust. This study is among the few studies that have identified hydrogen cyanide to be among the VOCs emitted from diesel exhaust. It also showed that neat biodiesel had the highest number of oxygenated VOCs peaks despite the diesel engine used. Lastly, it was shown that increasing the oxygen content of the fuel does not necessarily mean that oxygenated VOC emissions will increase.
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Hudson, Neale Alan. « Investigation of mechanisms governing emission of odorants ». Thesis, Queensland University of Technology, 2009. https://eprints.qut.edu.au/32001/1/Neale_Hudson_Thesis.pdf.
Texte intégralRésumé :
The literature identifies several models that describe inter-phase mass transfer, key to the emission process. While the emission process is complex and these models may be more or less successful at predicting mass transfer rates, they identify three key variables for a system involving a liquid and an air phase in contact with it:
• A concentration (or partial pressure) gradient driving force;
• The fluid dynamic characteristics within the liquid and air phases, and
• The chemical properties of the individual components within the system.
In three applied research projects conducted prior to this study, samples collected with two well-known sampling devices resulted in very different odour emission rates. It was not possible to adequately explain the differences observed. It appeared likely, however, that the sample collection device might have artefact effects on the emission of odorants, i.e. the sampling device appeared to have altered the mass transfer process. This raised the obvious question:
Where two different emission rates are reported for a single source (differing only in the selection of sampling device), and a credible explanation for the difference in emission rate cannot be provided, which emission rate is correct?
This research project aimed to identify the factors that determine odour emission rates, the impact that the characteristics of a sampling device may exert on the key mass transfer variables, and ultimately, the impact of the sampling device on the emission rate itself.
To meet these objectives, a series of targeted reviews, and laboratory and field investigations, were conducted. Two widely-used, representative devices were chosen to investigate the influence of various parameters on the emission process. These investigations provided insight into the odour emission process generally, and the influence of the sampling device specifically.
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Lamkaddam, Houssni. « Etude en atmosphère simulée de la formation d'Aérosol Organique Secondaire issue de la photooxydation du n-dodécane : impact des paramètres environnementaux ». Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1128/document.
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L’aérosol organique secondaire (AOS), fraction majoritaire de l’aérosol submicronique, joue un rôle important sur la santé, l’environnement et le climat. L’évaluation de son impact constitue un véritable enjeu pour la communauté scientifique. Toutefois, nos connaissances actuelles sur les processus de formation d’AOS et sa composition chimique sont encore très lacunaires, et en l’occurrence, limitent le développement des modèles atmosphériques permettant de quantifier les impacts des AOS sur la qualité de l’air et le système climatique. Ainsi, l’objectif de ce travail est de produire un ensemble de données expérimentales fournissant des points de contrainte afin d’évaluer et d’améliorer les modèles. Pour ce faire, la formation d’AOS a été étudiée à partir de la photooxydation d’un précurseur modèle, le n-dodécane, dans la chambre de simulation atmosphérique CESAM. La composition chimique a été élucidée par des techniques spectrométriques et chromatographiques permettant d’identifier les différentes espèces constituant la phase gazeuse et particulaire. En particulier, de nouveaux mécanismes en phase condensée ont été proposés afin d’expliquer la formation des acides carboxyliques et des lactones, identifiés pour la première fois dans l’AOS d’un alcane. Ces derniers pourront être implémentés dans les modèles. Une grande diversité de conditions environnementales, telles que la température, l’humidité relative et la présence/absence de particules préexistantes, a été prise en compte dans ces travaux. Notamment, l’étude de l’influence de la température a mis en évidence une faible sensibilité de ce paramètre sur les rendements de production d’AOS. Tandis que l’étude sur l’effet de l’humidité relative, elle, a montré que l’ajout d’eau dans le système réactionnel au-delà de 5% abaisse les rendements d’AOS de près d’un facteur 2 en comparaison à des conditions sèches. Ainsi, la formation potentielle d’AOS sous ces différentes conditions a permis d’aboutir à des paramétrisations directement utilisables par les modélisateurs. Une caractérisation des effets de paroi dans CESAM, i.e. les pertes en phase gazeuse et particulaire, a également été menéeSecondary Organic Aerosol (SOA), the major fraction of the submicron aerosol, plays a key role on health, environment and climate. The evaluation of its impacts is a real challenge for the scientific community. Our current knowledge of SOA formation processes and chemical composition is still very deficient and limit the development of atmospheric models to quantify the impacts of SOA on air quality and climate system. Therefore, the aim of this work is to produce a set of experimental data to use to constrain and improve the models. To do that, the SOA formation has been studied from the photooxidation of a model precursor, n-dodecane, in the CESAM environmental chamber. The chemical composition has been investigated by spectrometric and chromatographic techniques which allowed us to identify the reaction products constituting the gaseous and particulate phases. In particular, new condensed phase mechanisms have been proposed to explain the formation of carboxylic acids and lactones, identified for the first time. These could be implemented in the models. A wide variety of environmental conditions, such as temperature, relative humidity and the presence/absence of preexisting particles, have been taken into account in this work. The study of the temperature influence has shown a low sensitivity of this parameter on the SOA production. While the study relative humidity effect has shown that adding water to the reaction system beyond 5% lowers SOA yields by almost a factor of 2 in comparison to dry conditions. The SOA formation potential, under these conditions, has been evaluated, and resulted in parameterizations which could be useful for modelers. Furthermore, a characterization of the wall effects in CESAM, i.e. gas and particulate phase wall losses, has been carried out
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Shirsat, Abhijeet R. « Understanding the Allure and Danger of Fake News in Social Media Environments ». Bowling Green State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1530280814598288.
Texte intégralLivres sur le sujet "Chamba Masks"
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Nkya, Ananilea. 20 years of Tanzania Media Women's Association (TAMWA) : Moving the agenda for social transformation in Tanzania. Dar es Salaam, Tanzania : Published by E&D Vision Pub. on behalf of TAMWA, 2008.
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Ananilea, Nkya, Lema Elieshi et Chama cha Waandishi wa Habari Wanawake Tanzania., dir. 20 years of Tanzania Media Women's Association (TAMWA) : Moving the agenda for social transformation in Tanzania. Dar es Salaam, Tanzania : Published by E&D Vision Pub. on behalf of TAMWA, 2008.
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Ananilea, Nkya, Lema Elieshi et Chama cha Waandishi wa Habari Wanawake Tanzania., dir. 20 years of Tanzania Media Women's Association (TAMWA) : Moving the agenda for social transformation in Tanzania. Dar es Salaam, Tanzania : Published by E&D Vision Pub. on behalf of TAMWA, 2008.
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Kŭndae taejung maech'e wa chapka. Sŏul : Yŏngnak, 2015.
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Canada. Parliament. House of Commons. Bill : An act to amend the Criminal code, 1892, as to marks on merchandise. Ottawa : S.E. Dawson, 2003.
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Gans, Evelien, et Remco Ensel, dir. The Holocaust, Israel and 'the Jew'. NL Amsterdam : Amsterdam University Press, 2016. http://dx.doi.org/10.5117/9789089648488.
Texte intégralRésumé :
This book is the first comprehensive study of postwar antisemitism in the Netherlands. It focuses on the way stereotypes are passed on from one decade to the next, as reflected in public debates, the mass media, protests and commemorations, and everyday interactions. The Holocaust, Israel and 'the Jew' explores the ways in which old stories and phrases relating to 'the stereotypical Jew' are recycled and modified for new uses, linking the antisemitism of the early postwar years to its enduring manifestations in today's world. The Dutch case is interesting because of the apparent contrast between the Netherlands' famous tradition of tolerance and the large numbers of Jews who were deported and murdered in the Second World War. The book sheds light on the dark side of this so-called 'Dutch paradox,' in manifestations of aversion and guilt after 1945. In this context, the abusive taunt 'They forgot to gas you' can be seen as the first radical expression of postwar antisemitism as well as an indication of how the Holocaust came to be turned against the Jews. The identification of 'the Jew' with the gas chamber spread from the streets to football stadiums, and from verbal abuse to pamphlet and protest. The slogan 'Hamas, Hamas all the Jews to the gas' indicates that Israel became a second marker of postwar antisemitism. The chapters cover themes including soccer-related antisemitism, Jewish responses, philosemitism, antisemitism in Dutch-Moroccan and Dutch- Turkish communities, contentious acts of remembrance, the neo-Nazi tradition, and the legacy of Theo van Gogh. The book concludes with a lengthy epilogue on 'the Jew' in the politics of the radical right, the attacks in Paris in 2015, and the refugee crisis. The stereotype of 'the Jew' appears to be transferable to other minorities. Now also available as paperback!
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Gans, Evelien, et Remco Ensel, dir. The Holocaust, Israel and 'the Jew'. NL Amsterdam : Amsterdam University Press, 2017. http://dx.doi.org/10.5117/9789462986084.
Texte intégralRésumé :
This book is the first comprehensive study of postwar antisemitism in the Netherlands. It focuses on the way stereotypes are passed on from one decade to the next, as reflected in public debates, the mass media, protests and commemorations, and everyday interactions. The Holocaust, Israel and 'the Jew' explores the ways in which old stories and phrases relating to 'the stereotypical Jew' are recycled and modified for new uses, linking the antisemitism of the early postwar years to its enduring manifestations in today's world. The Dutch case is interesting because of the apparent contrast between the Netherlands' famous tradition of tolerance and the large numbers of Jews who were deported and murdered in the Second World War. The book sheds light on the dark side of this so-called 'Dutch paradox,' in manifestations of aversion and guilt after 1945. In this context, the abusive taunt 'They forgot to gas you' can be seen as the first radical expression of postwar antisemitism as well as an indication of how the Holocaust came to be turned against the Jews. The identification of 'the Jew' with the gas chamber spread from the streets to football stadiums, and from verbal abuse to pamphlet and protest. The slogan 'Hamas, Hamas all the Jews to the gas' indicates that Israel became a second marker of postwar antisemitism. The chapters cover themes including soccer-related antisemitism, Jewish responses, philosemitism, antisemitism in Dutch-Moroccan and Dutch- Turkish communities, contentious acts of remembrance, the neo-Nazi tradition, and the legacy of Theo van Gogh. The book concludes with a lengthy epilogue on 'the Jew' in the politics of the radical right, the attacks in Paris in 2015, and the refugee crisis. The stereotype of 'the Jew' appears to be transferable to other minorities.
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Medwed, Mameve. How Elizabeth Barrett Browning saved my life. Waterville, Me : Thorndike Press, 2006.
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How Elizabeth Barrett Browning saved my life. New York : Morrow, 2006.
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Pandit, 1st Pallvi. Mass Literacy Campaign and the Targeted New Delivery System under Saakshar Bharat Mission-2012 in Chamba District of Himachal Pradesh. Selfypage Developers Pvt Ltd, 2022.
Trouver le texte intégralChapitres de livres sur le sujet "Chamba Masks"
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Rentala, Girish Srivatsa, et Yimin Zhu. « Investigating the Ability of Immersive Virtual Environments to Facilitate Occupant Thermal State Data Collection Involving Face Masks ». Dans CONVR 2023 - Proceedings of the 23rd International Conference on Construction Applications of Virtual Reality, 100–108. Florence : Firenze University Press, 2023. http://dx.doi.org/10.36253/10.36253/979-12-215-0289-3.10.
Texte intégralRésumé :
This study examines the capability of an immersive virtual environment (IVE–based) experimental protocol to support occupant thermal state (sensation, acceptability, and comfort) data collection when participants wear face masks. Specifically, the goal is to see if there is a change in local thermal states due to face covering and would such a change affect overall thermal states. A between-subject experiment was conducted with fifty-four participants (27 masked; 27 unmasked) who were exposed to three-step temperatures (18.3ºC, 23.8ºC, and 29.4ºC) in a climate chamber under both cooling and heating sequences. In masked IVE experiments, participants donned a face mask and viewed the chamber's virtual model on a head-mounted display. In contrast, in unmasked IVE experiments, participants didn't use a face mask. Skin temperatures and overall/local thermal state responses were collected during the experiments. They were then statistically compared between masked IVE and unmasked IVE experiments. The results suggest that forehead temperature was significantly different under all step temperatures in the cooling sequence, with mean forehead temperature being larger in masked IVE than in unmasked IVE experiments. Furthermore, in masked IVE experiments, thermal sensation in the forehead, neck, and upper-back increased while the thermal acceptability in those same skin sites decreased, but this difference was not statistically significant. Also, in masked IVE experiments, the overall thermal sensation increased, whereas both the overall thermal acceptability and comfort decreased when compared with unmasked IVE experiments. Nonetheless, this difference was not statistically significant. To summarize, wearing a face mask didn't affect the participant's overall and local thermal states in IVEs, although few statistical differences were observed in skin temperatures
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Rentala, Girish Srivatsa, et Yimin Zhu. « Investigating the Ability of Immersive Virtual Environments to Facilitate Occupant Thermal State Data Collection Involving Face Masks ». Dans CONVR 2023 - Proceedings of the 23rd International Conference on Construction Applications of Virtual Reality, 100–108. Florence : Firenze University Press, 2023. http://dx.doi.org/10.36253/979-12-215-0289-3.10.
Texte intégralRésumé :
This study examines the capability of an immersive virtual environment (IVE–based) experimental protocol to support occupant thermal state (sensation, acceptability, and comfort) data collection when participants wear face masks. Specifically, the goal is to see if there is a change in local thermal states due to face covering and would such a change affect overall thermal states. A between-subject experiment was conducted with fifty-four participants (27 masked; 27 unmasked) who were exposed to three-step temperatures (18.3ºC, 23.8ºC, and 29.4ºC) in a climate chamber under both cooling and heating sequences. In masked IVE experiments, participants donned a face mask and viewed the chamber's virtual model on a head-mounted display. In contrast, in unmasked IVE experiments, participants didn't use a face mask. Skin temperatures and overall/local thermal state responses were collected during the experiments. They were then statistically compared between masked IVE and unmasked IVE experiments. The results suggest that forehead temperature was significantly different under all step temperatures in the cooling sequence, with mean forehead temperature being larger in masked IVE than in unmasked IVE experiments. Furthermore, in masked IVE experiments, thermal sensation in the forehead, neck, and upper-back increased while the thermal acceptability in those same skin sites decreased, but this difference was not statistically significant. Also, in masked IVE experiments, the overall thermal sensation increased, whereas both the overall thermal acceptability and comfort decreased when compared with unmasked IVE experiments. Nonetheless, this difference was not statistically significant. To summarize, wearing a face mask didn't affect the participant's overall and local thermal states in IVEs, although few statistical differences were observed in skin temperatures
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Gross, Richard S. « CHAMP, Mass Displacements, and the Earth’s Rotation ». Dans First CHAMP Mission Results for Gravity, Magnetic and Atmospheric Studies, 174–79. Berlin, Heidelberg : Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-540-38366-6_26.
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Nawab, Asghar, Dhruva Jyoti Basu, Sanjeev Kumar Yadav et Parikshit Gautam. « Impact of Mass Mortility of Gharial Gavialis gangeticus (Gmelin, 1789) on its Conservation in the Chambal River in Rajasthan ». Dans Faunal Heritage of Rajasthan, India, 221–29. Cham : Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-01345-9_9.
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König, Valentina, Michael Rom et Siegfried Müller. « A Coupled Two-Domain Approach for Transpiration Cooling ». Dans Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 33–49. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53847-7_2.
Texte intégralRésumé :
Abstract Transpiration cooling is an innovative cooling concept where a coolant is injected through a porous ceramic matrix composite (CMC) material into a hot gas flow. This setting is modeled by a two-domain approach coupling two models for the hot gas domain and the porous medium to each other by coupling conditions imposed at the interface. For this purpose, appropriate coupling conditions, in particular accounting for local mass injection, are developed. To verify the feasibility of the two-domain approach numerical simulations in 3D are performed for two different application scenarios: a subsonic thrust chamber and a supersonic nozzle.
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Shi, Chuang, Ludwig Grunwaldt, Jean-Claude Raimondo, Franz-Heinrich Massmann et Sheng Yuan Zhu. « Determination of the Offset of CHAMP GPS Antenna with Respect to Satellite’s Mass Center ». Dans First CHAMP Mission Results for Gravity, Magnetic and Atmospheric Studies, 38–41. Berlin, Heidelberg : Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-540-38366-6_6.
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McCulloch, Jock, et Pavla Miller. « Technologies, Care and Repatriations : 1926–1966 ». Dans Mining Gold and Manufacturing Ignorance, 345–69. Singapore : Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-8327-6_13.
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AbstractUntil 1950, there was no effective chemotherapy for tuberculosis. Treatment consisted of an enhanced diet, isolation, and skilled nursing—methods which were expensive and not greatly effective. The centrepiece of the mines’ management of tuberculosis was repatriation of sick miners, without notification of local authorities, isolation of those with infective disease, or education of those around them on how to avoid infection. This approach enhanced the mines’ profitability but confounded every principle of public health. In the 1950s, the development of mass miniature radiography and the discovery of new drugs for the treatment of tuberculosis radically changed the available technologies of care. In discussing international standards of compensation for occupational lung disease, ILO held that the worker’s history of dust exposure, a clinical examination and radiographic findings had to be considered. The Chamber of Mines used mass miniature radiography for a different purpose: those with dusted lungs were identified at entry medicals and then repatriated without compensation. Where chemotherapy was provided to sick miners, the treatment rarely lasted more than a month; as a result, most patients developed drug resistant tuberculosis. Today, South Africa and its labour-sending regions have one of the world’s highest rates of multi-drug-resistant TB.
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Bonolis, Luisa. « Bruno Touschek (1921–1978). The Path to Electron-Positron Collisions ». Dans Springer Proceedings in Physics, 9–31. Cham : Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-23042-4_2.
Texte intégralRésumé :
AbstractThe 100th anniversary of Bruno Touschek’s birth also marks 60 years since the first beams of electrons and positrons circulated in AdA, the first ever matter-antimatter collider, built in Frascati National Laboratories following Touschek’s visionary proposal of February 1960. Touschek’s path to such idea is briefly outlined, beginning with his early years as a student—first in Vienna and later in Germany—through his first experiences with Rolf Widerøe’s betatron and the electron synchrotron accelerator in Glasgow after the war, along with his relationships with the fathers of modern physics in Europe, to his arrival in Italy, where crucial reflections during the 1950s led him to the profound belief that matter-antimatter annihilations should become a primary goal for future physics. Based on these premises, Touschek and his collaborators dared to take on the challenge of realizing what at the time seemed an “unthinkable idea”: keep beams of electrons and positron circulating for hours in the vacuum chamber of a storage ring and making them collide.
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Lee, Christine U., et James F. Glockner. « Case 13.25 ». Dans Mayo Clinic Body MRI Case Review, sous la direction de Christine U. Lee et James F. Glockner, 661–62. Oxford University Press, 2014. http://dx.doi.org/10.1093/med/9780199915705.003.0349.
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27-year-old man with a 3-month history of chest pain and mild shortness of breath Four-chamber SSFP image (Figure 13.25.1) demonstrates a large well-defined mass in the right ventricular free wall. Four-chamber double (Figure 13.25.2) and triple (Figure 13.25.3) inversion recovery FSE images with proton density- and T2-weighting reveal mildly decreased signal intensity relative to myocardium. Four-chamber MDE image (...
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Dumas, Alexandre. « 33 Where, Probably, MoliÈRe Formed His First Idea of the Bourgeois Gentilhomme ». Dans The Man in the Iron Mask. Oxford University Press, 2008. http://dx.doi.org/10.1093/owc/9780199537259.003.0034.
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D’Artagnan found Porthos in the adjoining chamber, but no longer an irritated Porthos, or a disappointed Porthos, but Porthos radiant, blooming, fascinating, and chatting with Molière, who was looking upon him with a species of idolatry, and as a man would who had...
Actes de conférences sur le sujet "Chamba Masks"
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Ling, Kow-Je, Kungchi Shao, Chao-Kuo Lee et Jin-Su Lee. « A Model for Calculation of the Mask Function in Thin Film Coating ». Dans Optical Interference Coatings. Washington, D.C. : Optica Publishing Group, 1995. http://dx.doi.org/10.1364/oic.1995.mb19.
Texte intégralRésumé :
Thin film coating has found wide applications in optical systems. One of the main requirements an optical thin film must meet is its uniformity. To achieve the demanded uniformity, conventional efforts include special design of the vacuum chamber configuration [1], use of the masks [2], etc. Masks have also been utilized to coat non-uniform films [3]. In principle, a film of arbitrary thickness distribution can be made with an appropriate mask. Usually the shape, the size and the position of the mask are determined empirically. We presented a model to calculate the film thickness and/or the mask function.
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Haddad, A., R. Boukhanouf et C. Buffone. « Testing of vapour chamber used in electronics cooling ». Dans HEAT AND MASS TRANSFER 2006. Southampton, UK : WIT Press, 2006. http://dx.doi.org/10.2495/ht060271.
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Wang, Yue, Guizhen Lu, Jincai Lin, Jin Zhang et Min Qu. « The Measurement in Reverberation Chamber ». Dans 2009 International Conference on Management and Service Science (MASS). IEEE, 2009. http://dx.doi.org/10.1109/icmss.2009.5304581.
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Mao, Zhigang, Tiecheng Zhou, Michael Grimbergen, Darin Bivens, David Knick, Renee Koch, Madhavi Chandrachood, Jeff Chen, Ibrahim Ibrahim et Ajay Kumar. « Plasma optical emission analysis for chamber condition monitor ». Dans Photomask and NGL Mask Technology XVI, sous la direction de Kunihiro Hosono. SPIE, 2009. http://dx.doi.org/10.1117/12.824306.
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Mao, Zhigang, Xiaoyi Chen, David Knick, Michael Grimbergen, Madhavi Chandrahood, Ibrahim Ibrahim et Ajay Kumar. « In-situ chamber clean for chromium etch application ». Dans Photomask and NGL Mask Technology XV, sous la direction de Toshiyuki Horiuchi. SPIE, 2008. http://dx.doi.org/10.1117/12.793080.
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Hoehn, A., J. Clawson, A. G. Heyenga, P. Scovazzo, K. S. Sterrett, L. S. Stodieck, P. W. Todd et M. H. Kliss. « Mass Transport in a Spaceflight Plant Growth Chamber ». Dans International Conference On Environmental Systems. 400 Commonwealth Drive, Warrendale, PA, United States : SAE International, 1998. http://dx.doi.org/10.4271/981553.
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Mungekar, Hemant, Bruno Geoffrion, Bikram Kapoor, Naren Dubey, Mak Salimian, Michael Cox et Paddy Krishnaraj. « Heat and Mass Transport in HDP-CVD Chamber ». Dans ASME 2003 Heat Transfer Summer Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/ht2003-47030.
Texte intégralRésumé :
HDP-CVD reactors are used for Shallow Trench Isolation (STI), Inter Metal Dielectric (IMD) and Inter Layer Dielectric (ILD) applications for logic and memory device fabrication. As device dimension shrinks, the trend has been to use lower pressure and higher plasma density for gap-fill with higher aspect ratio (AR). Higher AR gapfill in addition to higher throughput is achieved by running multiple wafers between a chamber clean, present a unique set of challenges for heat and mass-transfer in an HDP-CVD reactor. This paper describes some of the new state-of-the-art hardware innovations specifically developed to meet these challenges. In particular, heat transfer to plasma facing materials, fluid mechanics, and transport of sub-micron sized particles in the plasma environment of an HDP-CVD reactor are explored.
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Lin, Wei-Keng, Wen-Hua Zhang et Pei-Hsun Wu. « Thermal Diffusivity Measurement of Vapor Chamber ». Dans The 3rd World Congress on Momentum, Heat and Mass Transfer. Avestia Publishing, 2018. http://dx.doi.org/10.11159/icmfht18.104.
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Zhao, Yuejun, Jonathan B. Boreyko, Meng-Han Chiang, Christopher H. Baker et Chuan-Hua Chen. « Beetle Inspired Electrospray Vapor Chamber ». Dans ASME 2009 Second International Conference on Micro/Nanoscale Heat and Mass Transfer. ASMEDC, 2009. http://dx.doi.org/10.1115/mnhmt2009-18498.
Texte intégralRésumé :
We present the proof-of-concept for a biomimetic electrospray vapor chamber (BEVAC) which can potentially eliminate the wick structures and thermal interface materials used in conventional vapor chambers, and enable direct cooling of the backside of a microprocessor. This vapor chamber has a beetle-inspired superhydrophobic condenser with hydrophilic bumps on which condensate of the working fluid accumulates. The condensate is returned to the evaporator by electrostatic forces (electrospray atomization). We have demonstrated this novel liquid return mechanism with an open-system BEVAC prototype in which an external voltage is applied between a wickless evaporator and a microfabricated condenser with hybrid wettability.
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Minotti, A., et Enrico Sciubba. « Large Eddy Simulation of an ultra-micro combustion chamber ». Dans Turbulence, Heat and Mass Transfer 6. Proceedings of the Sixth International Symposium On Turbulence, Heat and Mass Transfer. Connecticut : Begellhouse, 2009. http://dx.doi.org/10.1615/ichmt.2009.turbulheatmasstransf.410.
Texte intégralRapports d'organisations sur le sujet "Chamba Masks"
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Bell, J., et L. Hand. Calculation of Mass Transfer Coefficients in a Crystal Growth Chamber through Heat Transfer Measurements. Office of Scientific and Technical Information (OSTI), avril 2005. http://dx.doi.org/10.2172/918405.
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Bajwa, Abdullah, Tim Kroeger et Timothy Jacobs. PR-457-17201-R04 Residual Gas Fraction Estimation Based on Measured Engine Parameters - Phase IV. Chantilly, Virginia : Pipeline Research Council International, Inc. (PRCI), septembre 2021. http://dx.doi.org/10.55274/r0012176.
Texte intégralRésumé :
Based on experimental characterization of the scavenging behavior of a cross-scavenged, piston-aspirated, two-stroke, natural gas engine in phase III of the current project, a computationally inexpensive simple scavenging model was improved in this phase. Experimental results using fast nondispersive infrared (NDIR) CO2 measurements from the cylinder and the exhaust, as well as experiments using unburned fuel pre-mixed in the scavenging chamber as a tracer for short-circuiting during scavenging, were used in this phase to validate the improved model. The model represents the fundamental phenomenological characteristics revealed by those experiments. The experiments and literature show that scavenging takes place by the following phenomena: blowdown, displacement of residuals by incoming air, mixing of residuals and air, and short-circuiting of fresh air. To reflect this, the improved hybrid model features the following: isentropic blowdown, non-isothermal perfect displacement, non-isothermal perfect mixing, and a concurrent direct short-circuiting of air (unmixed with residuals). The validated improved hybrid model rectified the primary shortcoming of the phase III model. By adding the discrete short-circuiting zone, trapped mass could be modeled at both medium and high crankshaft speeds, whereas the phase III model could not capture the full scope of scavenging inefficiencies at medium speed using its perfect mixing stage alone. Furthermore, using the hybrid model to predict NOx using an exponential NO and shy;x-TER curve fit revealed that the improved phase IV hybrid model predicts NOx approximately as well as the experimentally-calculated TER from the phase III experiments. Additionally, GT-Power, a 1D fluid dynamics and engine simulation software, was used to identify whether hybrid model tuning could be aided by relatively inexpensive 1D simulation rather than CFD or fast NDIR experiments. Using three-pressure analysis (with in-cylinder, exhaust, and scavenging chamber pressures as boundary conditions) and scavenging profiles derived from the hybrid model itself, GT-Power was shown to be a plausible tool for scavenging model tuning.
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Jacobs, Timothy, et Jacob Hedrick. PR-457-14201-R03 Variable NG Composition Effects in LB 2S Compressor Engines - Prediction Enhancement. Chantilly, Virginia : Pipeline Research Council International, Inc. (PRCI), août 2017. http://dx.doi.org/10.55274/r0011406.
Texte intégralRésumé :
Phase II of the project has focused on improving the initial analysis performed in the first phase by enhancing the various aspects of predictive combustion for lean burn spark ignition natural gas engines under variable composition fueling. These enhancements have incorporated validation data from a Cooper-Bessemer GMVH-10C3 engine located in New Jersey, which improves upon the lack of field data to bound the scope of composition variation. In simulation related endeavors, effort was made to improve the fundamental combustion physics related parameters, namely laminar flame speed, by developing a code base for distributed computing of the chemical kinetics solver, Cantera, and was key to improving upon the chemistry modeling used in the previous phase. Methods to improve numerical convergence were employed to reduce the time to solve large mechanisms, such as the Saudi Aramco Mechanism (v1.3). Modeling of pre-chamber combustion from first principles, common input experimental heat release analysis and simulated heat release generation were additional components of improving model matching with pre-chambered engines. In its current state, manual optimization is required to tune the heat release curves based on guesses about the initial charge mass state, scavenging efficiency, fuel delivery and thereby the trapped equivalence ratio.
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Boily-Auclair, É., P. Mercier-Langevin, P. S. Ross et D. Pitre. Alteration and ore assemblages of the LaRonde Zone 5 (LZ5) deposit and Ellison mineralized zones, Doyon-Bousquet-LaRonde mining camp, Abitibi, Quebec. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329637.
Texte intégralRésumé :
The LaRonde Zone 5 (LZ5) mine is part of the Doyon-Bousquet-LaRonde mining camp and is located in the southern part of the Abitibi greenstone belt in northwestern Quebec. The LZ5 deposit consists of three stacked mineralized corridors: Zone 4, Zone 4.1, and Zone 5. Zones 4 and 4.1 are discontinuous satellite mineralized corridors, whereas Zone 5 represents the main mineralized body. The mineralized zones of the LZ5 deposit and adjacent Ellison property (Ellison A and B zones) are hosted in the strongly-deformed, 2699-2695 Ma transitional to calcalkaline, intermediate to felsic, volcanic and volcaniclastic rocks of the Bousquet Formation upper member, which is part of the Blake River Group (2704-2695 Ma). Zones 4, 4.1, and 5 at the LZ5 mine are hosted in intermediate volcanic and volcaniclastic rocks of the Westwood andesitic to rhyodacitic unit (unit 5.1a), which forms the base of the upper member of the Bousquet Formation. The Ellison Zone A is hosted higher up in the stratigraphic sequence within a newly described intermediate volcanic unit. The Ellison Zone B is hosted in felsic volcanic and volcaniclastic rocks of the Westwood feldsparphyric rhyolite dome (subunit 5.3a-(b)). Mineralization in all three zones of the LZ5 deposit consists of discordant networks of millimeter- to centimeter-thick pyrite ±chalcopyrite ±sphalerite ±pyrrhotite veins and veinlets (10-20 % of the volume of the rock) and, to a lesser extent, very finely disseminated pyrite and boudinaged veins (less than or equal to 5 vol. % each) in strongly altered host rocks. Gold commonly occurs as microscopic inclusions in granoblastic pyrite and at the triple junction between recrystallized grains. The veins, stockworks, and disseminations were intensely folded and transposed in the steeply south-dipping, east-west trending S2 foliation. The vein network is at least partly discordant to the stratigraphy. A distal alteration halo envelops the LZ5 mineralized corridors and consists of a sericite-carbonate-chlorite- feldspar ±biotite assemblage. A proximal sericite-carbonate-chlorite-pyrite-quartz- feldspar-biotite ±epidote alteration assemblage is present within the LZ5 mineralized zones. A local proximal alteration assemblage of sericite-quartz-pyrite is also locally developed within Zone 4 and Zone 5 of the LZ5 deposit. Mass gains in Fe2O3 (t) and K2O, and mass losses in CaO, MgO, Na2O, and locally SiO2, are characteristic of the LZ5 alteration zones. The Ellison zone A and B are similar to LZ5 in terms of style of mineralization, but thin (10-20 cm) veins or bands of semi-massive to massive, finely recrystallized disseminated pyrite (0.1-1 mm) are distinctive. Chalcopyrite and sphalerite are also slightly more abundant in the mineralized corridors of the Ellison property and are usually associated with elevated gold grades. The zones are also slightly richer than at LZ5 in terms of gold and silver content, but narrower and less continuous in general. The Ellison Zone A is characterized by gains in Fe2O3 (t) and K2O and losses in CaO, MgO, Na2O, and SiO2. Gains in Fe2O3 (t) and local gains in K2O, MgO, and MnO, and losses in CO2, Na2O, P2O5, and SiO2, characterize the felsic host rocks of the Zone B corridor. The style of mineralization at LZ5 (pyrite ±chalcopyrite veins and veinlets, ±disseminated pyrite with low base metal content), its setting (i.e. in rocks of intermediate composition at the base of the upper member of the Bousquet Formation), and the geometry of its ore zones (stacked lenses of sulfide veins and veinlets, without massive sulfide lenses) differ from the other major deposits of the Doyon-Bousquet-LaRonde mining camp. Despite these differences, this study indicates that the LZ5 and Ellison mineralized corridors are of synvolcanic hydrothermal origin and have most likely been formed by convective circulation of seawater below the seafloor. An influx of magmatic fluids from the Mooshla synvolcanic intrusive complex or its parent magma chamber could explain the Au enrichment at LZ5, as has been suggested for other deposits of the camp. Evidence for a pre-deformation synvolcanic mineralization at LZ5 includes ductile deformation and recrystallization of the sulfides, the stacked nature of its ore zones, subconcordant alteration halos that envelop the mineralized corridors, evidence that the mineralized system was already active when the LZ5 lenses were deposited and control on mineralization by primary volcanic features such as the permeability and porosity of the volcanic rocks.
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The Bank at Work - Commonwealth Bank Head Office - Banking Chamber - Ground Floor - Bank staff wearing face masks during the Influenza Epidemic of 1919 - 1919. Reserve Bank of Australia, mars 2022. http://dx.doi.org/10.47688/rba_archives_pn-006877.
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