Relevant bibliographies by topics / Si ratios

Academic literature on the topic 'Si ratios'

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Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Si ratios"

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Dufton, P. L., and A. E. Kingston. "SI II line ratios in the sun." Astrophysical Journal 289 (February 1985): 844. http://dx.doi.org/10.1086/162948.

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Djeniže, S., A. Srećković, and S. Bukvić. "On the line intensity ratios of prominent Si II, Si III, and Si IV multiplets." Spectrochimica Acta Part B: Atomic Spectroscopy 65, no. 1 (January 2010): 61–65. http://dx.doi.org/10.1016/j.sab.2009.11.004.

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Yoshida, Takashi, Hideyuki Umeda, and Ken’ichi Nomoto. "Si Isotopic Ratios in Supernovae for Presolar Grains." Astrophysical Journal 631, no. 2 (October 2005): 1039–50. http://dx.doi.org/10.1086/432654.

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Takechi, Kazushige, Mitsuru Nakata, Shinya Yamaguchi, Hiroshi Tanabe, and Setsuo Kaneko. "Amorphous In–Sn–Si–O Thin-Film Transistors Having Various Si Compositional Ratios." Japanese Journal of Applied Physics 49, no. 2 (February 22, 2010): 028002. http://dx.doi.org/10.1143/jjap.49.028002.

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Pradell, Trinitat, D. Crespo, Narcis Clavaguera, and Maria T. Clavaguera-Mora. "Nanocrystallisation in Finemet Alloys with Different Si/B Ratios." Materials Science Forum 307 (March 1999): 83–88. http://dx.doi.org/10.4028/www.scientific.net/msf.307.83.

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Pradell, Trinitat, D. Crespo, Narcis Clavaguera, and Maria T. Clavaguera-Mora. "Nanocrystallisation in Finemet Alloys with Different Si/B Ratios." Journal of Metastable and Nanocrystalline Materials 1 (March 1999): 83–88. http://dx.doi.org/10.4028/www.scientific.net/jmnm.1.83.

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Lugaro, Maria, Ernst Zinner, Roberto Gallino, and Sachiko Amari. "Si Isotopic Ratios in Mainstream Presolar SiC Grains Revisited." Astrophysical Journal 527, no. 1 (December 10, 1999): 369–94. http://dx.doi.org/10.1086/308078.

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Petrovic, Ivan, and Alexandra Navrotsky. "Thermochemistry of Na-faujasites with varying Si/Al ratios." Microporous Materials 9, no. 1-2 (March 1997): 1–12. http://dx.doi.org/10.1016/s0927-6513(96)00060-0.

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Kloetstra, K. R., H. W. Zandbergen, and H. van Bekkum. "MCM-41 type materials with low Si/Al ratios." Catalysis Letters 33, no. 1-2 (March 1995): 157–63. http://dx.doi.org/10.1007/bf00817055.

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Filiberto, J. "The Mars/Earth dichotomy in Mg/Si and Al/Si ratios: Is it real?" American Mineralogist 91, no. 2-3 (February 1, 2006): 471–74. http://dx.doi.org/10.2138/am.2006.2110.

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Dissertations / Theses on the topic "Si ratios"

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Delvigne, Camille. "The Archaean silicon cycle insights from silicon isotopes and Ge/Si ratios in banded iron formations, palaeosols and shales." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209652.

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The external silicon cycle during the Precambrian (4.5-0.5 Ga) is not well understood despite its key significance to apprehend ancient dynamics at the surface of the Earth. In the absence of silicifying organisms, external silicon cycle dramatically differs from nowadays. Our current understanding of Precambrian oceans is limited to the assumption that silicon concentrations were close to saturation of amorphous silica. This thesis aims to bring new insights to different processes that controlled the geochemical silicon cycle during the Archaean (3.8-2.5 Ga). Bulk rock Ge/Si ratio and Si isotopes (δ30Si) offer ideal tracers to unravel different processes that control the Si cycle given their sensitivity to fractionation under near-surface conditions.

First, this study focuses on Si inputs and outputs to ocean over a limited time period (~2.95 Ga Pongola Supergroup, South Africa) through the study of a palaeosol sequence and a contemporaneous banded iron formation. The palaeosol study offers precious clues in the comprehension of Archaean weathering processes and Si transfer from continent to ocean. Desilication and iron leaching were shown to be the major Archaean weathering processes. The occurrence of weathering residues issued of these processes as major component in fine-grained detrital sedimentary mass (shales) attests that identified weathering processes are widely developed and suggest an important dissolved Si flux from continent to the ocean. In parallel, banded iron formations (BIFs), typically characterised by alternation of iron-rich and silica-rich layers, represent an extraordinary record of the ocean-derived silica precipitation throughout the Precambrian. A detailed study of a 2.95 Ga BIF with excellent stratigraphic constraints identifies a seawater reservoir mixed with significant freshwater and very limited amount of high temperature hydrothermal fluids as the parental water mass from which BIFs precipitated. In addition, the export of silicon promoted by the silicon adsorption onto Fe-oxyhydroxides is evidenced. Then, both Si- and Fe-rich layers of BIFs have a common source water mass and a common siliceous ferric oxyhydroxides precursor. Thus, both palaeosols and BIFs highlight the significance of continental inputs to ocean, generally under- estimated or neglected, as well as the close link between Fe and Si cycles.

In a second time, this study explores secular changes in the Si cycle along the Precambrian. During this timespan, the world ocean underwent a progressive decrease in hydrothermal inputs and a long-term cooling. Effects of declining temperature over the oceanic Si cycle are highlighted by increasing δ30Si signatures of both chemically precipitated chert and BIF through time within the 3.8-2.5 Ga time interval. Interestingly, Si isotope compositions of BIF are shown to be kept systematically lighter of about 1.5‰ than contemporaneous cherts suggesting that both depositions occurred through different mechanisms. Along with the progressive increase of δ30Si signature, a decrease in Ge/Si ratios is attributed to a decrease in hydrothermal inputs along with the development of large and widespread desilication during continental weathering.

Le cycle externe du silicium au précambrien (4.5-0.5 Ga) reste mal compris malgré sa position clé dans la compréhension des processus opérant à la surface de la Terre primitive. En l’absence d’organismes sécrétant un squelette externe en silice, le cycle précambrien du silicium était vraisemblablement très différent de celui que nous connaissons à l’heure actuelle. Notre conception de l’océan archéen est limitée à l’hypothèse d’une concentration en silicium proche de la saturation en silice amorphe. Cette thèse vise à une meilleure compréhension des processus qui contrôlaient le cycle géochimique externe du silicium à l’archéen (3.8-2.5 Ga). Dans cette optique, le rapport germanium/silicium (Ge/Si) et les isotopes stables du silicium (δ30Si) représentent des traceurs idéaux pour démêler les différents processus contrôlant le cycle du Si.

Dans un premier temps, cette étude se focalise sur les apports et les exports de silicium à l’océan sur une période de temps restreinte (~2.95 Ga Pongola Supergroup, Afrique du Sud) via l’étude d’un paléosol et d’un dépôt sédimentaire de précipitation chimique quasi-contemporain. L’étude du paléosol apporte de précieux indices quant aux processus d’altération archéens et aux transferts de silicium des continents vers l’océan. Ainsi, la désilicification et le lessivage du fer apparaissent comme des processus majeurs de l’altération archéenne. La présence de résidus issus de ces processus d’altération en tant que composants majeurs de dépôts détritiques (shales) atteste de la globalité de ces processus et suggère des flux significatifs en silicium dissout des continents vers l’océan. En parallèle, les « banded iron formations » (BIFs), caractérisés par une alternance de niveaux riches en fer et en silice, représentent un enregistrement extraordinaire et caractéristique du précambrien de précipitation de silice à partir de l’océan. Une étude détaillée d’un dépôt de BIFs permet d’identifier une contribution importante des eaux douces dans la masse d’eau à partir de laquelle ces roches sont précipitées. Par ailleurs, un mécanisme d’export de silicium via absorption sur des oxyhydroxydes de fer est mis en évidence. Ainsi, les niveaux riches en fer et riche en silice constituant les BIFs auraient une même origine, un réservoir d’eau de mer mélangée avec des eaux douces et une contribution minime de fluides hydrothermaux de haute température, et un même précurseur commun. Dès lors, tant les paléosols que les BIFs mettent en évidence l’importance des apports continentaux à l’océan, souvent négligés ou sous estimés, ainsi que le lien étroit entre les cycles du fer et du silicium.

Dans un second temps, cette étude explore l’évolution du cycle du silicium au cours du précambrien. Durant cette période, l’océan voit les apports hydrothermaux ainsi que sa température diminuer. Dans l’intervalle de temps 3.8-2.5 Ga, les effets de tels changements sur le cycle du silicium sont marqués par un alourdissement progressif des signatures isotopiques des cherts et des BIFs. Le fort parallélisme entre l’évolution temporelle des compositions isotopiques des deux précipités met en évidence leur origine commune, l’océan. Cependant, les compositions isotopiques des BIFs sont systématiquement plus légères d’environ 1.5‰ que les signatures enregistrées pas les cherts. Cette différence est interprétée comme le reflet de mécanismes de dépôts différents. L’alourdissement progressif des compositions isotopiques concomitant à une diminution des rapports Ge/Si reflètent une diminution des apports hydrothermaux ainsi que la mise en place d’une désilicification de plus en plus importante et/ou généralisée lors de l’altération des continents.


Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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Meyer, Anne. "Étude expérimentale des réactions ¹³N(a,p)¹⁶O et ³⁰P(p,g)³¹S, et impact sur les abondances isotopiques extrêmes en ¹³C, ¹⁵N et ³⁰Si dans les grains pré-solaires." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASS013.

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On retrouve dans les météorites primitives des grains qui se sont condensés dans différents environnements stellaires et sont restés intacts après la formation du système solaire. L'identification du site d'origine de ces grains pré-solaires est effectuée grâce à la comparaison entre les abondances isotopiques mesurées et celles prédites par les modèles stellaires. Nous présentons dans ce manuscrit les analyses de deux expériences effectuées à l'installation ALTO avec le spectromètre magnétique split-pole, visant à réduire les incertitudes associées à deux réactions jouant un rôle dans la production des isotopes utilisés pour identifier les grains de novæ. Ces derniers sont caractérisés par des abondances extrêmes en ¹³C, ¹⁵N et ³⁰Si, mais la découverte dans certains grains d'isotopes caractéristiques de la nucléosynthèse dans les supernovæ à effondrement de coeur (CCSN) a remis en question cette origine. La première étude concerne l'impact du taux de la réaction ¹³N(a,p)¹⁶O sur les abondances en ¹³C prédites par de récents modèles de CCSN. Nous procédons à une ré-évaluation du taux de cette réaction en utilisant une méthode Monte Carlo pour obtenir des incertitudes statistiques. Les largeurs partielles alpha des états du noyau composé ¹⁷F sont déterminées en se basant sur les propriétés des états analogues du noyau miroir ¹⁷O qui ont été mesurées en utilisant la réaction de transfert alpha ¹³C(7Li,t)¹⁷O. Nous nous intéressons ensuite à la réaction ³⁰P(p,g)³¹S, qui est une des dernières réactions dont l'incertitude du taux a un impact important sur les prédictions faites par les modèles de novæ classiques, notamment des abondances en ³⁰Si. Pour réduire les incertitudes sur les propriétés spectroscopiques du noyau composé ³¹S, une étude de la réaction ³¹P(³He,t)³¹S a été effectuée. Les tritons et les protons de décroissance venant des états peuplés du ³¹S ont été détectés simultanément à l'aide du spectromètre et de détecteurs silicium à pistes. L'étude des corrélations angulaires proton est présentée et les rapports de branchement extraits
Primitive meteorites contain several types of dust grains that condensed in different stellar environments and survived destruction in the early Solar System. The stellar sources where these presolar grains come from are identified through comparisons between measurements of isotopic abundances and predictions by stellar models. In this manuscript is presented a detailed analysis of two experiments performed at the ALTO facility, using the split-pole magnetic spectrometer, aiming at reducing the nuclear uncertainties associated to two reactions which rate uncertainty affects the synthesis of isotopes used to identify putative novae grains. These grains are characterised by extremely high ¹³C, ¹⁵N and ³⁰Si isotopic abundances, but isotopic signatures found in a few grains indicate also a possible core-collapse supernovae (CCSN) origin. We first study the impact of the ¹³N(a,p)¹⁶O reaction rate uncertainty on ¹³C abundances predicted by recent CCSN models. We perform a re-evaluation of this reaction rate using a Monte Carlo approach to obtain meaningful statistical uncertainties. Alpha partial widths of states in the ¹⁷F compound nucleus are determined using the spectroscopic informations of the analog states in the ¹⁷O mirror nucleus that were measured using the ¹³C(7Li,t)¹⁷O alpha-transfer reaction. We then study the ³⁰P(p,g)³¹S reaction, which is one of the few remaining reactions which rate uncertainty has a strong impact on classical novae model predictions, in particular for ³⁰Si abundances. To reduce the nuclear uncertainties associated to this reaction, we studied the ³¹P(³He,t)³¹S reaction. Triton and proton decays from the populated states in ³¹S were detected simultaneously using the spectrometer and silicon strip detectors. The study of the angular correlations of proton decays is presented and branching ratios are extracted
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Wang, Shiwei. "Advanced air fuel ratio control of automotive si engines." Thesis, Liverpool John Moores University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438766.

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Gustafsson, Karin. "Ion Current Dependence on Operating Condition and Ethanol Ratio." Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8053.

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This masters thesis investigates the possibility to estimate the ethanol content in the fuel using ion currents. Flexible fuel cars can be run on gasoline-ethanol blends with an ethanol content from0 to 85 percentage. It is important for the engine control system to have information about the fuel. In todays cars the measurements of the fuel blend are done by a sensor. If it is possible to do this with ion currents this can be used to detect if the sensor is broken, and then estimate the ethanol content until the sensor gets fixed. The benefit

of using ion currents is that the signal is measured directly from the spark plug and therefore no extra hardware is needed. To be able to see how the ethanol ratio affects the ion currents, the dependencies of the operating point have been investigated. This has been done by a literature review and by measurements in a Saab 9-3. Engine speed, load, ignition timing, lambda and spark plugs effects on the ion currents are especially studied. A black box model for the ion currents dependence on operating point is developed. This model describes the engine speed, load and ignition timing dependencies well, but it can not be used to estimate the ethanol ratio.

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Rosén, Anna. "Air/Fuel Ratio Control of an SI-Engine Under Normal Operation Conditions." Thesis, Linköping University, Department of Electrical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2448.

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Emission from cars today is one of the biggest environmental issues, hence stringent government standards have been introduced to decrease emission. Car companies do not only have to satisfy government standards, but also meet consumer demands on increased fuel economy and good drivablility. This report will introduce controllers designed to control the air/fuel ratio in an SI engine. The engine model used is simplified. The engine components modelled include the inlet manifold, fuel dynamics, combustion and exhaust sensor.

Nonlinearities and delays are inherent in the engine dynamics and as such a Smith Predictor is utilised as the basis for controller structure to compensate for the delays. Here the Smith Predictor is combined with feedforwarding of the mass air charge, which is estimated from both the inlet and combustion models. Therefore different ways of merging the estimates are also explored.

A real engine was not accesible, thus simulators were implemented using data sets provided by General Motors. Model errors were introduced to test the controllers performance. The proposed methods should be tested on a real engine to ensure that this isa viable approach, as the simulations show it maybe promising to use in practice.

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Bai, Yang. "Studies on SI engine simulation and air/fuel ratio control systems design." Thesis, Brunel University, 2013. http://bura.brunel.ac.uk/handle/2438/8342.

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More stringent Euro 6 and LEV III emission standards will immediately begin execution on 2014 and 2015 respectively. Accurate air/fuel ratio control can effectively reduce vehicle emission. The simulation of engine dynamic system is a very powerful method for developing and analysing engine and engine controller. Currently, most engine air/fuel ratio control used look-up table combined with proportional and integral (PI) control and this is not robust to system uncertainty and time varying effects. This thesis first develops a simulation package for a port injection spark-ignition engine and this package include engine dynamics, vehicle dynamics as well as driving cycle selection module. The simulations results are very close to the data obtained from laboratory experiments. New controllers have been proposed to control air/fuel ratio in spark ignition engines to maximize the fuel economy while minimizing exhaust emissions. The PID control and fuzzy control methods have been combined into a fuzzy PID control and the effectiveness of this new controller has been demonstrated by simulation tests. A new neural network based predictive control is then designed for further performance improvements. It is based on the combination of inverse control and predictive control methods. The network is trained offline in which the control output is modified to compensate control errors. The simulation evaluations have shown that the new neural controller can greatly improve control air/fuel ratio performance. The test also revealed that the improved AFR control performance can effectively restrict engine harmful emissions into atmosphere, these reduce emissions are important to satisfy more stringent emission standards.
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Klein, Markus. "Single-Zone Cylinder Pressure Modeling and Estimation for Heat Release Analysis of SI Engines." Doctoral thesis, Linköping : Department of Electrical Engineering, Linköping University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-9863.

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Gerty, Michael D. "Effects of operating conditions, compression ratio, and gasoline reformate on SI engine knock limits." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32369.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.
Includes bibliographical references (p. 133-135).
A set of experiments was performed to investigate the effects of air-fuel ratio, inlet boost pressure, hydrogen rich fuel reformate, and compression ratio on engine knock behavior. For each condition the effect of spark timing on torque output was measured. Knock limited spark advance was then found for a range of octane number (ON) for each of three fuel types; primary reference fuels (PRFs), toluene reference fuels (TRFs), and test gasolines. A new combustion phasing parameter based on the timing of 50% mass fraction burned, ternled "combustion retard", was found to correlate well to engine performance. Increasing air- fuel ratio increases the combustion retard required to just avoid knock for PRFs and has little effect for TRFs. Combustion retard also increases more with inlet pressure and decreases more with reformate addition for PRFs than for TRFs. Both fuel types responded similarly to increased compression ratio. The trends for gasoline are about halfway between PRFs and TRFs. Experiments were also performed to determine the response of mid-load indicated efficiency to air-fuel ratio, load, and compression ratio. At a compression ratio of 9.8:1, relative net efficiency improvement is about 2.5% per unit compression ratio. Efficiency peaks at about 14:1 with a maximum benefit of 6-7%. Detailed chemical kinetics were combined with a cylinder pressure based end-gas modeling methodology to successfully predicted the response of PRFs to compression ratio and air-fuel ratio, and the response of TRFs to boost. The difference between the response of PRFs and TRFs to air-fuel ratio was also captured.
(cont.) Constant volume chemistry modeling found that hydrogen slows alkane autoignition reactions by consuming hydroxy radicals in the end gas. Reforming 30% of the fuel entering an engine decreases the required fuel quality 10 ON or more, which would allow increased compression ratio or increased turbocharging without increasing combustion retard. A simplified analysis indicates that increasing compression ratio and downsizing the engine to maintain constant maximum torque would increase fuel efficiency by about 9%. Turbocharging and downsizing would increase fuel efficiency by about 16%.
by Michael D. Gerty.
S.M.
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Parker, Mohamed Habeeb. "Hydrocracking of n-C16 over MFI Zeolite Nano-sheets - Effect of the Si/Al Ratio." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29306.

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The combination of MFI zeolite nano-sheets with competitive adsorption of water (H2O) in hydrocracking of long-chain paraffins presents a promising opportunity to produce diesel with high yield and with high cetane number. Thus, in wet hydrocracking of a long-chain paraffin (n-hexadecane (n-C16)) over MFI nano-sheets, it was investigated whether catalytic activity increased with increasing number of Brønsted acid (H + ) sites (decreasing silicon-to-aluminium (Si/Al) ratio), while secondary cracking remained completely suppressed. Also, it was investigated whether more Al atoms could be incorporated into the framework of MFI nano-sheets by modifying the new synthesis method. It was demonstrated that the new synthesis method, which utilizes C22H45–N + (CH3)2–C6H12–N + (CH3)2–C6H13 (C22-6-6) as structure-directing agent (SDA), could be extended to various Si/Al ratios in the range 25 – 100. The nano-sheets exhibited extra-framework Al (EFAl) species. Nano-sheets with Si/Al = 75 exhibited an oddly large amount of EFAl species compared to the other nano-sheets. For nano-sheets with Si/Al = 75, a high fraction of the EFAl species may have formed during calcination of the ammonium form and may encompass flexible Al species with predominantly Al in octahedral coordination (AlVI). Nano-sheets were loaded with 0.9 wt% platinum (Pt) via incipient wetness impregnation (IWI). Pt/nano-sheets with Si/Al = 25, 50 and 100 exhibited similar and high Pt dispersion (γPt). In contrast, Pt/nano-sheets with Si/Al = 75 exhibited a very low γPt, which was probably a result of the abundance, nature and/or location of EFAl species present in the support. In dry hydrocracking of n-C16, the catalytic activity increased with decreasing Si/Al ratio, strongly suggesting that the number of H+ sites increased with decreasing Si/Al ratio. Nano-sheets with Si/Al = 75 most likely contained AlVI species associated with Brønsted acidity, supporting the presence of flexible AlVI species. In wet hydrocracking of n-C16, at a constant and sufficiently high γPt, the activity increased with increasing number of H+ sites (decreasing Si/Al ratio), while secondary cracking remained completely suppressed. Pt/nano-sheets with Si/Al = 75 displayed a lower activity than 2 Pt/nano-sheets with Si/Al = 100, which may be a result of the very low γPt of Pt/nano-sheets with Si/Al = 75, underlining the importance of high γPt. For Pt/nano-sheets with Si/Al = 25, 50 and 100, H2O favoured linear cracking products at low cracking yields. In contrast, for Pt/nano-sheets with Si/Al = 75, H2O favoured branched cracking products, which may be a result of Pt sites on the external surface of the support being too far from the H+ sites inside the micropores. The new synthesis method could be extended to a modified SDA, namely C22H45–N + (CH3)2–C6H12–N + (CH3)2–C3H7 (C22-6-3), at various Si/Al ratios in the range 25 – 100. Replacing the terminal –C6H13 group in C22-6-6 with –C3H7 resulted in an increase in the framework Al (FAl) content of MFI nano-sheets with Si/Al ≥ 50, with the increase being the most pronounced for nano-sheets with Si/Al = 50. This was due to the increased occupancy of the zeolite framework by the hydrophilic region of C22-6-3 in comparison to the hydrophilic region of C22-6-6 under the given set of synthesis conditions, since –C3H7 was less bulky than –C6H13. Calcined nano-sheets were loaded with 1 wt% Pt via competitive ion exchange (CIE). In dry and wet hydrocracking of n-C16, the activity increased with decreasing Si/Al ratio and in wet hydrocracking, secondary cracking was not completely suppressed up to high conversions. This was probably due to the presence of additional H+ sites generated after SDA removal. H2O favoured linear cracking products at low cracking yields. Sodium (Na+ ) ion-exchanged nano-sheets were loaded with 1 wt% Pt via CIE. The average Pt size (dPt) of the Pt/Na+ nano-sheets were larger than the dPt of the Pt/calcined nano-sheets, which may be a result of the nature and/or location of EFAl species present in the Na+ supports. In dry and wet hydrocracking of n-C16, differences in activity were observed and in wet hydrocracking, secondary cracking was not completely suppressed up to high conversions. This was probably due to insufficient intimacy between H+ sites and Pt sites such that the rate was controlled by diffusion of olefinic intermediates from H+ sites to Pt sites and vice versa. H2O favoured linear cracking products at low cracking yields.
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YOO, KYESANG. "Development of Clean Catalyst for Alkylation of Isobutane with 2-Butene." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1060899661.

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Books on the topic "Si ratios"

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Ju an si wei. Xianggang: Tian chuang chu ban she you xian gong si, 2014.

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Marie, Robertson Eleanor. Si tu m'abandonnes. Paris: J'ai lu, 2009.

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Marie, Robertson Eleanor. Si tu m'abandonnes. Paris: Éd. France loisirs, 2009.

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Marie, Robertson Eleanor. Si tu m'abandonnes. Paris: J'ai lu, 2014.

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Marie, Robertson Eleanor. Si tu m'abandonnes. Neuillly-sur-Seine: M. Lafon, 2009.

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Si da huo bi hui lü bian dong yan jiu. Xi'an Shi: bXi'an di tu chu ban she, 2003.

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Nambuk ŭi hwanggŭm piyul ŭl ch'ajasŏ: Nam-Pukhan chikkyo si kyŏlche t'onghwa e kwanhan yŏn'gu = The golden ratio for reunification. Sŏul T'ŭkpyŏlsi: Tosŏ Ch'ulp'an Haengbok Enŏji, 2015.

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Ji yu xing xi mo xing de wo guo bao xian gong si jing zheng li ping jia yan jiu: Jiyu xingxi moxing de woguo baoxian gongsi jingzhengli pingjia yanjiu. Chengdu Shi: Sichuan da xue chu ban she, 2009.

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Qu yu dian li shi chang xia fa dian ji tuan gong si jing jia jue ce. Beijing: Zhongguo dian li chu ban she, 2009.

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Si no fuera por estos raticos. Lid, 2014.

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Book chapters on the topic "Si ratios"

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Sukhoruchkin, S. I., and Z. N. Soroko. "Energy levels and branching ratios for Si-26 (Silicon-26)." In Tables of Excitations of Proton- and Neutron-Rich Unstable Nuclei, 128–30. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-75278-3_77.

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Sukhoruchkin, S. I., and Z. N. Soroko. "Energy levels and branching ratios for Si-34 (Silicon-34)." In Tables of Excitations of Proton- and Neutron-Rich Unstable Nuclei, 132. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-75278-3_79.

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Dortch, Quay, Nancy N. Rabalais, R. Eugene Turner, and Naureen A. Qureshi. "Impacts of changing Si/N ratios and phytoplankton species composition." In Coastal and Estuarine Studies, 37–48. Washington, D. C.: American Geophysical Union, 2001. http://dx.doi.org/10.1029/ce058p0037.

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Van Nieuwerburgh, Lies, Ingrid Wänstrand, and Pauli Snoeijs. "Growth and C:N:P ratios in copepods grazing on N- or Si-limited phytoplankton blooms." In Biology of the Baltic Sea, 57–72. Dordrecht: Springer Netherlands, 2004. http://dx.doi.org/10.1007/978-94-017-0920-0_5.

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Lee, Chang Seop, Sun Hye Noh, Sung Soo Kim, Soong Hyuk Suh, and Charles H. F. Peden. "Physical and Catalytic Properties of the Na-Exchanged Y-Zeolites with Different Si/Al Ratios." In Key Engineering Materials, 720–31. Stafa: Trans Tech Publications Ltd., 2005. http://dx.doi.org/10.4028/0-87849-958-x.720.

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Shah, Abdul Wahid, Seong-Ho Ha, Young-Ok Yoon, and Shae K. Kim. "Heat Treatment of Al–Mg–Si–Mn Alloys with Varying Mg/Si Ratio." In Light Metals 2022, 199–206. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92529-1_27.

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Gradoboev, Alexander, Irina Matveeva, Dmitry Ryabov, Roman Vakhromov, Victor Mann, and Aleksandr Krokhin. "Influence of the Mg/Si Ratio on Speed Extrusion of 6XXX Alloys." In Light Metals 2022, 322–28. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92529-1_45.

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Li, Ning, Bolong Li, Tongbo Wang, and Zuoren Nie. "Effects of Mg/Si Ratio on the Microstructure of Aging Al–Mg–Si Alloys Containing Er and Zr Elements." In Springer Proceedings in Physics, 679–87. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-5944-6_66.

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Delijić, Kemal, V. Asanović, and Dragan Radonjić. "The Effect of Thermo-Mechanical Processing on the Properties of some Al-Fe-Si Alloys with High Fe/Si Ratio." In Materials Science Forum, 559–63. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-441-3.559.

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Autef, A., E. Joussein, G. Gasgnier, and S. Rossignol. "Effect of SI/K Ratio Alkaline Solutions on Mechanical Properties of Geomaterial Compounds." In Developments in Strategic Materials and Computational Design V, 29–38. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2015. http://dx.doi.org/10.1002/9781119040293.ch3.

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Conference papers on the topic "Si ratios"

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Frings, Patrick, Marcus Oelze, Friedhelm von Blanckenburg, and Franziska Schubring. "Quantifying biotic and abiotic Si fluxes in the Critical Zone with Ge/Si ratios along a gradient of erosion rates." In Goldschmidt2021. France: European Association of Geochemistry, 2021. http://dx.doi.org/10.7185/gold2021.4653.

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Gupta, N. K., S. An, and Y. B. Gianchandani. "A monolithic 48-stage Si-micromachined Knudsen pump for high compression ratios." In 2012 IEEE 25th International Conference on Micro Electro Mechanical Systems (MEMS). IEEE, 2012. http://dx.doi.org/10.1109/memsys.2012.6170116.

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Chuang, Linus C., Michael Moewe, Shanna Crankshaw, and Connie Chang-Hasnain. "Effects of V/III Ratios for InP Nanowires Grown on Si Substrates." In CLEO 2007. IEEE, 2007. http://dx.doi.org/10.1109/cleo.2007.4452749.

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Wang, Yu-Cian, Kenji Araki, Kyotaro Nakamura, Kan-Hua Lee, Takefumi Kamioka, Nobuaki Kojima, Yoshio Ohshita, and Masafumi Yamaguchi. "Enhancement of Si Photovoltaic Module by Introducing III-V/Si Hybrid Configurations and Cost Evaluations under Various Cost Ratios of III-V/Si Photovoltaics." In 2017 IEEE 44th Photovoltaic Specialists Conference (PVSC). IEEE, 2017. http://dx.doi.org/10.1109/pvsc.2017.8366113.

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Van Blarigan, Andrew, Darko Kozarac, Reinhard Seiser, Robert Cattolica, Jyh-Yuan Chen, and Robert Dibble. "Experimental Study of Methane Fuel Oxycombustion in an SI Engine." In ASME 2012 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/icef2012-92109.

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An experimental investigation of the thermal efficiency, combustion efficiency, and CoV IMEP, of methane fuel oxycombustion in an SI engine has been carried out. Compression ratio, spark-timing, and oxygen concentration were all varied. A variable compression ratio SI engine was operated on both wet and dry EGR working fluids, with results illustrating that the efficiency of the engine operating with a large amount of EGR was significantly reduced relative to methane-in-air operation over all oxygen concentrations and compression ratios. The maximum thermal efficiency of wet EGR, dry EGR, and air was found to be 23.6%, 24.2%, and 31.4%, respectively, corresponding to oxygen volume fractions of 29.3%, 32.7% and 21%. Combustion efficiency was above 98% for wet EGR and approximately 96% for dry EGR. CoV IMEP was low for both cases. The much lower efficiency of both EGR cases relative to air is primarily a result of the reduced specific-heat ratio of the EGR working fluids relative to air working fluid.
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Verhelst, Sebastian, Roger Sierens, and Stefaan Verstraeten. "Development of a Simulation Code for Hydrogen Fuelled SI Engines." In ASME 2006 Internal Combustion Engine Division Spring Technical Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/ices2006-1317.

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Hydrogen is an attractive alternative energy carrier, which could make harmful emissions, global warming and the insecurity concerning oil supply a thing of the past. Hydrogen internal combustion engines can be introduced relatively easily, from a technological as well as from an economic point of view. This paper discusses the development of a model for the combustion of hydrogen in spark ignition engines, which has lead to a simulation program that can assist the optimization of these engines. The importance of a laminar burning velocity correlation taking stretch and instability effects into account is shown. The effects are particularly strong for the highly diffusive hydrogen molecule. In this paper, a laminar burning velocity correlation published previously by two of the authors is combined with a number of turbulent burning velocity models in a quasi-dimensional two-zone combustion model framework. After calibration of the combustion model for a reference condition, simulation results are compared with experimental cylinder pressure data recorded on a single cylinder hydrogen engine. Correspondence between simulation and measurement is shown for varying equivalence ratio, ignition timing and compression ratio. All models performed well for varying ignition timings and compression ratios; the real test proved to be the ability of the models to predict the effects of a varying equivalence ratio, this lead to a clear distinction in the models.
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Lin, Tzu-Ching, Shu-Chia Shiu, Keng-Lam Pun, Hong-Jhang Syu, and Ching-Fuh Lin. "Layer transfer of crystalline Si thin film by metal-assisted chemical etching concerning different H2O2/HF ratios." In 2012 IEEE 38th Photovoltaic Specialists Conference (PVSC). IEEE, 2012. http://dx.doi.org/10.1109/pvsc.2012.6317633.

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Lawrenz, W., J. Köhler, F. Meier, W. Stolz, R. Wirth, W. H. Bloss, R. R. Maly, E. Wagner, and M. Zahn. "Quantitative 2D LIF Measurements of Air/Fuel Ratios During the Intake Stroke in a Transparent SI Engine." In International Fuels & Lubricants Meeting & Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1992. http://dx.doi.org/10.4271/922320.

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Chung, C. K., and J. J. Jhu. "Effect of nitrogen flow ratios on microstructure and mechanical properties of nanocomposite Ti-Si-N thin flims." In 2009 4th IEEE International Conference on Nano/Micro Engineered and Molecular Systems. IEEE, 2009. http://dx.doi.org/10.1109/nems.2009.5068695.

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Gurumurthy, V., Uppalapati Babu, and L. Kumararaja. "Performance of SI engine fuelled with producer gas at various spark timings and compression ratios – A review." In NATIONAL CONFERENCE ON ENERGY AND CHEMICALS FROM BIOMASS (NCECB). AIP Publishing, 2020. http://dx.doi.org/10.1063/5.0005828.

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Reports on the topic "Si ratios"

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Shul, R. J., C. G. Willison, C. T. Sullivan, S. H. Kravitz, L. Zhang, and T. E. Zipperian. Deep high-aspect ratio Si etching for advanced packaging technologies. Office of Scientific and Technical Information (OSTI), May 1998. http://dx.doi.org/10.2172/650284.

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Kuo, Hao-Chung, and G. R. Lin. Study on Locally Confined Deposition of Si Nanocrystals in High-Aspect-Ratio Si Nano-Pillar Arrays for Nano-Electronic and Nano-Photonic Applications II. Fort Belvoir, VA: Defense Technical Information Center, December 2010. http://dx.doi.org/10.21236/ada533435.

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Breiland, W., and M. Coltrin. Si deposition rates in a two-dimensional CVD (chemical vapor deposition) reactor and comparisons with model calculations. Office of Scientific and Technical Information (OSTI), October 1989. http://dx.doi.org/10.2172/5370171.

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Hofman, G. L., J. Rest, J. L. Snelgrove, T. Wiencek, and S. Koster van Groos. Aluminum-U{sub 3}Si{sub 2} interdiffusion and its implications for the performance of highly loaded fuel operating at higher temperatures and fission rates. Office of Scientific and Technical Information (OSTI), December 1996. http://dx.doi.org/10.2172/414402.

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Campbell, Bryan, Michel Magnan, Benoit Perron, and Molivann Panot. Modélisation de règles budgétaires pour l’après-COVID. CIRANO, January 2022. http://dx.doi.org/10.54932/nesj4065.

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Le but du présent travail est d'évaluer l'apport que pourrait avoir l’imposition de règles budgétaires sur le retour au déficit 0 annoncé pour 2027-28 dans le budget 2021-22. Notre approche simule de nombreux scénarios économiques futurs, chacun incorporant des règles budgétaires. Cet exercice est répété un grand nombre de fois, ce qui génère une distribution des déficits budgétaires pour chaque horizon temporel désiré et pour chaque règle budgétaire analysée. Cette approche s’appuie sur une étude historique des écarts budgétaires pour développer un modèle de simulations des écarts qui prend en compte leur évolution dans le temps et leur corrélation entre les composantes budgétaires à l’aide d’un modèle à facteur. Notre approche en deux étapes permet de simuler des déficits futurs : en nous basant sur la valeur simulée du facteur, les écarts des diverses composantes budgétaires sont déterminés. Ensuite, pour chaque composante du budget, le revenu ou dépense avéré est obtenu directement de la valeur prévue au budget (qui reflète l’application d’une règle budgétaire) et de l’écart. La valeur simulée du déficit peut ainsi être calculée. Nous étudions par simulation l’impact de deux grandes classes de règles budgétaires. La première limite la croissance des dépenses de chaque mission à 5% par année alors que la deuxième permet une hausse plus élevée pour la santé et les services sociaux, 6%, que pour les autres missions, 2%. Chacune de ces règles est analysée sous un scénario de référence et deux spécifications alternatives : une première permet un effet de rétroaction et impose une diminution des dépenses si les cibles budgétaires sont ratées, alors que la deuxième considère une augmentation de l’incertitude économique et budgétaire. Dans ce rapport, nous prenons comme point de départ la trajectoire de déficits prévue par le Ministère dans les documents budgétaires de mars dernier. En particulier, nous imposons un retour à l’équilibre budgétaire lors de l’année fiscale 2027-28 et ajustons les revenus pour refléter cette contrainte. Nos résultats de simulation se trouvent aux tableaux 1 et 2 et sont synthétisés aux tableaux 3 et 4.
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POWER FLOW ANALYSIS OF BRIDGE U-RIB STIFFENED PLATES BASED ON THE CONCEPT OF STRUCTURAL INTENSITY. The Hong Kong Institute of Steel Construction, August 2022. http://dx.doi.org/10.18057/icass2020.p.061.

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Due to its advantages of good mechanical properties, simple appearance and strong adaptability, the steel box girder is being widely utilized in urban bridges. The noise radiated by steel box girders subjected to vehicle impacts has the characteristics of wide-spectrum, high-magnitude and control difficulty. U-rib stiffened roof, as a part of the steel box girder, directly bears the input load, which is the basis of studying the vibration of the steel box girder. Currently, the investigation on the vibro-acoustic performance of U-rib plates is very limited. With this regard, this paper introduces the concept of Structural Intensity (SI). The SI vector is calculated by the Finite Element (FE) method. The power flow is visualized by the self-programming post-processing code. The global and local vibration energy transmission characters of a U-rib stiffened plate under a harmonic nodal force are analyzed. Further, the influence of plate thickness is investigated. The optimum design is carried out based on the engineering standard dimensions. The research results indicate that increasing the thickness ratio of the U-rib to the baseplate is beneficial to reducing the vibration.
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