Relevant bibliographies by topics / CASCADE CYCLE

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'CASCADE CYCLE'

Author: Grafiati
Published: 11 September 2023

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Journal articles on the topic "CASCADE CYCLE"

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Woodward, John B. "The Rankine Topping Cycle Revisited." Journal of Ship Research 36, no. 01 (March 1, 1992): 91–98. http://dx.doi.org/10.5957/jsr.1992.36.1.91.

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Cascaded thermodynamic machines are familiar in marine engineering, even if the word "cascade" is not common currency in that field. The author refers to the almost universal practice of exhausting the working fluid (air) of a diesel engine into a gas turbine (the turbocharger, usually), followed by exhausting of that working fluid into a heat exchanger that energizes the working fluid (water) of yet another turbine. If the same practice is to be described in terms of the respective power cycles, we would probably say that the cascade consists of a Rankine cycle topped by a Brayton cycle which is in turn topped by a diesel cycle. In similar fashion, recognized nomenclature might describe the diesel component as the "topping cycle," and the Rankine as the "bottoming cycle." The topping/bottoming nomenclature usually implies two different working fluids, so that the Brayton cycle might be described as a subpart of the topping cycle.
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Lee, Ho Saeng, S. T. Oh, Jung In Yoon, S. G. Lee, and K. H. Choi. "Analysis of Cryogenic Refrigeration Cycle Using Two Stage Intercooler." Defect and Diffusion Forum 297-301 (April 2010): 1146–51. http://dx.doi.org/10.4028/www.scientific.net/ddf.297-301.1146.

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This paper presents the comparison of performance characteristics for the several natural gas liquefaction cycles. The liquefaction cycle with the staged compression was designed and simulated for improving the cycle efficiency using HYSYS software. This includes a cascade cycle with a two-stage intercooler which is consisted of a Propane, Ethylene and Methane cycle. In addition, these cycles are compared with a modified staged compression process. The key parameters of the above cascade cycles were compared and analyzed. The COP (Coefficient of Performance) of the cascade cycle with a two-stage intercooler and a modified staged compression process is 13.7% and 29.7% higher than that of basic cycle. Also, the yield efficiency of LNG (Liquefied Natural Gas) improved compared with the basic cycle by 28.5%.
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Fu, Lan Fang, He Xu Sun, and Yan Cai Zhu. "Sample Time Staggered One-Cycle Control Based on Three-Phase H-Bridge Cascade VSI." Advanced Materials Research 516-517 (May 2012): 1822–26. http://dx.doi.org/10.4028/www.scientific.net/amr.516-517.1822.

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The One-Cycle Control(OCC) technique not only provides fast dynamic response, but also can admirably suppress the perturbation yielded by dc source and eliminate the undesired harmonic contents.The cascade H-bridge VSI has very low dv/dt and distortion in the voltage output waveform.Sample time staggered one-cycle control（STS-OCC） based on three-phase H-bridge cascade VSI is proposed. It yields all of the advantages of the OCC and cascade VSI.The results of the simulation and analysis show that the STS-OCC technology has high equivalent work frequency, little switching loss and quick dynamic response speed, which means it is fit for the cascaded multilevel inverter.
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Yao, Shouguang, Likang Xu, and Liang Tang. "New cold-level utilization scheme for cascade three-level rankine cycle using the cold energy of liquefied natural gas." Thermal Science 23, no. 6 Part B (2019): 3865–75. http://dx.doi.org/10.2298/tsci171012239y.

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The topic of this study is the intermediate fluid vaporizer gasification system for a liquefied natural gas floating storage regasification unit. To reduce the loss of heat exchange, the primary distributary cascade three-level Rankine cycle is optimised based on the cascade three-level Rankine cycle that uses the cold energy of liquefied natural gas to generate power. The optimized primary distributary cascade three-level Rankine cycle is then compared with the original cascade three Rankine cycle established under the same conditions. Then, a secondary distributary cascade three-level Rankine cycle is proposed. Results show that under a liquefied natural gas flow of 175 t/h, the primary distributary cascade three-level Rankine cycle system exhibits a maximum net output power of 4130.72 kW and an exergy efficiency of 23.78%, which is higher than that of the typical cascade three-level Rankine cycle. Moreover, the net output power and exergy efficiency of the primary distributary cascade three-level Rankine cycle system increased by 3.71% and by 3.84%, respectively. The secondary distributary cascade three-level Rankine cycle system exhibits a maximum net output power of 4143.75 kW and an exergy efficiency of 23.85%.
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Xu, Likang, and Guihua Lin. "Simulation and optimization of liquefied natural gas cold energy power generation system on floating storage and regasification unit." Thermal Science, no. 00 (2020): 205. http://dx.doi.org/10.2298/tsci200404205x.

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In this paper, based on the idea of reducing heat exchanger exergy destruction and increasing turbine work, a new three-stage cascade Rankine system and a new four-stage cascade Rankine system is proposed to improve the cold energy utilization rate during liquefied natural gas(LNG) gasification on liquefied natural gas-floating storage and regasification unit. Then compare them with the original cascade Rankine cycle established under the same conditions. The results show that under the condition of 175 t/h LNG flow, the maximum net output power of the new three-stage cascade Rankine cycle system is 4593.31 kW, the exergy efficiency is 20.644%. The maximum net output power of the new four-stage cascade Rankine cycle system is 5013.93 kW, and the exergy efficiency is 22.509%. Compared with the original cascade Rankine cycle system, the maximum net output power of the new three-stage cascade Rankine cycle system and the new four-stage cascade Rankine cycle system is increased by 9.41% and 11.45%, respectively, and the system exergy efficiency is increased by 9.29% and 11.28%, respectively.
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Sun, Heng, Hong Mei Zhu, and Hong Wei Liu. "Process Simulations of the Cold Recovery Unit in a LNG CCHP System with Different Power Cycles." Applied Mechanics and Materials 90-93 (September 2011): 3026–32. http://dx.doi.org/10.4028/www.scientific.net/amm.90-93.3026.

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A CCHP system using LNG as the primary energy should integrate cold recovery unit to increase the total energy efficiency. A scheme of CCHP consisting of gas turbine-steam turbine combined cycle, absorption refrigeration unit, cold recovery unit and cooling media system is a system with high efficiency and operation flexibility. Three different power cycles using the cold energy of LNG is(are 或 were) presented and simulated. The results show that the cascade Rankine power cycle using ethylene and propane in the two cycles respectively has highest energy efficiency. However, the unit is most complex. The efficiency of ethylene Rankine power cycle is little lower than the cascade one, and is much higher than the traditional propane Rankine cycle. The complexity of ethylene cycle is identical to that of the propane cycle. The ethylene Rankine power cycle is the referred method of cold recovery in a CCHP system based on overall considerations.
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Rehberger, Max, and Michael Hiete. "Allocation Procedures for Generic Cascade Use Cases - An Evaluation Using Monte Carlo Analysis." Materials Science Forum 959 (June 2019): 32–45. http://dx.doi.org/10.4028/www.scientific.net/msf.959.32.

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Cascade use - a concept for increasing resource efficiency by multiple use of resources - gains in importance, in particular for bio-based materials. Allocation of environmental burdens and costs along the cascade chain plays a major role in deciding whether to establish a cascade or not. This highlights the need for a methodology for properly assessing different types of cascades. To provide guidance in terms of choice of allocation procedure available from life cycle assessment (LCA), Monte Carlo analysis is used. Especially hybrid, individually tailored allocation approaches can be evaluated in this way. The results show a high diversity of possible outcomes in terms of general allocation intensity (how much burden is shifted between steps of the cascade), rank reversals (exchange of positions inside the burden ranking) and variance of the overall results of the cascade allocation. Results are valuable for selecting an allocation procedure for cascade LCA and for further interpreting cascade models using specific allocation procedures.
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ROH, CHUL WOO, JIN WOO YOO, and MIN SOO KIM. "VAPOR REFRIGERANT INJECTION TECHNIQUES FOR HEAT PUMP SYSTEMS: THE LATEST LITERATURE REVIEW AND DISCUSSION." International Journal of Air-Conditioning and Refrigeration 22, no. 01 (March 2014): 1430002. http://dx.doi.org/10.1142/s201013251430002x.

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This paper reviews the latest and major research on vapor refrigerant injection techniques. Various vapor refrigerant injection techniques are discussed and compared. Compared to the basic vapor injection (VI) cycle, double-expansion VI cycle, accumulator-VI cycle and the VI cycle in a cascade system are briefly explained. Studies about these various VI cycles do not only prove the performance of VI cycles, but also show variations of VI cycles. Discussions about the fundamental issues of the VI cycle are also presented.
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Boahen and Choi. "A Study on the Performance of a Cascade Heat Pump for Generating Hot Water." Energies 12, no. 22 (November 12, 2019): 4313. http://dx.doi.org/10.3390/en12224313.

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The use of cascade heat pumps for hot water generation has gained much attention in recent times. The big question that has attracted much research interest is how to enhance the performance and energy saving potential of these cascade heat pumps. This study therefore proposed a new cycle to enhance performance of the cascade heat pump by adopting an auxiliary heat exchanger (AHX) in desuperheater, heater and parallel positions at the low stage (LS) side. The new cascade cycle with AHX in desuperheater position was found to have better performance than that with AHX at heater and parallel positions. Compared to the conventional cycle, heating capacity and coefficient of performance (COP) of the new cascade cycle with AHX in desuperheater position increased up to 7.4% and 14.9% respectively.
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Wu, Chih. "Power performance of a cascade endoreversible cycle." Energy Conversion and Management 30, no. 3 (January 1990): 261–66. http://dx.doi.org/10.1016/0196-8904(90)90008-m.

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Dissertations / Theses on the topic "CASCADE CYCLE"

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Desmons, Sarah. "Cycle de Calvin alternatif : catalyse chémo-enzymatique pour la transformation du dioxyde de carbone en carbohydrates et dérivés." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30200.

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Le manuscrit présente la conversion du dioxyde de carbone en sucres C3 et C4 à l'aide de réactions en cascade chimio-enzymatiques stéréocontrôlées. Le processus repose sur une stratégie en deux étapes avec (i) la réduction catalytique et sélective à 4 électrons du CO2 en un dérivé bis(boryl)acétal suivi (ii) de couplage enzymatique C-C stéréocontrôlé du dérivé bis(boryl)acétal en sucres C3 et C4. La stratégie développée est sans précédent et représente une nouvelle approche pour l'utilisation du CO2 comme source Cn pour la synthèse de biomolécules énantiomériquement pures importantes sur le plan industriel. Le premier chapitre est une étude bibliographique décrivant (i) une introduction à la chimie des sucres avec un focus particulier dédié à la production de sucres à partir de CO2 et de formaldéhyde comme sources C1 et (ii) la réduction sélective et catalytique à quatre électrons du CO2 à l'aide d'hydroborane et d'hydrosilane utilisés comme réducteur pour la formation de dérivés bis(boryl)acétal et bis(silyl)acétal ainsi que leur utilisation comme sources de formaldéhyde ou substituts de formaldéhyde pour la synthèse de produits à haute valeur ajoutée. Le deuxième chapitre présente la synthèse et la réactivité des dérivés bis(boryl)acétal et bis(silyl)acétal. Notamment, un nouveau dérivé bis(boryl)acétal a été synthétisé avec succès et isolé à l'échelle du gramme. Le troisième chapitre décrit la bioconversion stéréocontrôlée du dérivé bis(boryl)acétal synthétisé à partir du CO2 en sucres. Notamment, une réaction enzymatique en cascade a été réalisée pour la production d'un sucre C4 énantiomériquement pur en utilisant le CO2 comme seule source de carbone
The manuscript presents the conversion of carbon dioxide into C3 and C4 carbohydrates using stereocontrolled chemo-enzymatic cascade reactions. The process relies on a two-step strategy with (i) the catalytic and selective 4-electron reduction of CO2 into a bis(boryl)acetal derivative followed by (ii) the stereocontrolled bio-catalyzed C-C coupling of the bis(boryl)acetal derivative into carbohydrates. The strategy developed is unprecedented and represents a new exciting approach for the use of CO2 as a Cn source for the synthesis of valuable industrially relevant enantiomerically pure biomolecules. The first chapter is a bibliographic study describing (i) an introduction to carbohydrate chemistry with a special focus dedicated to the production of carbohydrates from CO2 and formaldehyde as C1 sources and (ii) the selective and catalytic four-electron reduction of CO2 using hydroborane and hydrosilane as reductants for the formation of bis(boryl)acetal and bis(silyl)acetal derivatives and their use as formaldehyde sources or formaldehyde surrogates for the synthesis of value-added product. The second chapter presents the synthesis and reactivity of bis(boryl)acetal and bis(silyl)acetal derivatives. Notably, a new isolable bis(boryl)acetal derivative was successfully synthesized and isolated on a gram scale. The third chapter describes the stereocontrolled bioconversion of the bis(boryl)acetal derivative synthetized from CO2 into carbohydrates. Notably, an enzymatic cascade reaction was performed for the production of an enantiomerically pure C4 carbohydrate using CO2 as the only carbon source
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Bauer, Tom. "Concevoir un produit pour plusieurs vies : Propositions pour la conception et l'évaluation environnementales de solutions en cascade." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAI076/document.

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Ces travaux de thèse s’intéressent à une stratégie de fin de vie naissante : le repurposing. Nous le définissons comme un processus industriel par lequel des produits en fin d’usage sont réutilisés dans des applications distinctes. À la fin de leur premier usage, les produits sont réintégrés dans la chaine industrielle en vue d’une nouvelle utilisation dans une autre application. On parle également d’utilisations en cascade. Le but avoué est la conservation de la valeur-ajoutée des produits, aussi longtemps que possible. Cette stratégie s’inscrit aux côtés d’autres stratégies de réutilisation plus connues telles que le réemploi et le remanufacturing.L’illustration principale de la littérature, qui constitue également notre terrain d’étude, concerne les batteries au lithium. Utilisées initialement dans les véhicules électriques, elles sont aujourd’hui recyclées lorsque leurs capacités de stockage diminuent de 20 à 30%. Prolonger leur durée de vie par une seconde application, e.g. un usage stationnaire, permettrait de différer les étapes de recyclage tout en maximisant le maintien de la valeur ajoutée lors de la fabrication. Malgré ces avantages, les exemples de transformations de produits pour des applications en cascade restent à l’état de démonstrateurs, en particulier parce qu’aujourd’hui ces produits et leur chaine de valeur ne sont pas conçus avec des stratégies supportant leur réutilisation.L’objectif de ces travaux est d’apporter aux équipes de conception une vision claire de ce qu’est la stratégie de réutilisation en cascade, de comment l’intégrer lors des étapes amont du processus de conception et de guider l’évaluation environnementale correspondante, afin de les accompagner pour une réelle industrialisation des produits repurposés. En ce sens, nous émettons trois propositions.La première consiste en une classification des caractéristiques propres aux solutions en cascade selon trois axes : le produit, le processus de (re)fabrication et le modèle d’affaire envisagé. À travers ce cadre, nous décrivons les dimensions et les caractéristiques des offres de produits repurposés. Elles sont alors utilisables pour l’établissement de compromis dès les phases amont de conception. Celles-ci sont issues d’une étude bibliographique couplée à des études de terrain.Notre deuxième proposition concerne le processus de conception de tels produits. En effet, plusieurs spécificités sont à prendre en compte en comparaison d’une activité de conception classique : récupération du produit en fin d’usage, applications ultérieures pas ou peu définies, besoins flous, usage influençant les performances, etc. Une étape de conception pour les produits repurposés devra donc être intégrée en amont du processus de repurposing afin d’optimiser les solutions ultérieures. En complément, plusieurs recommandations pour la conception d’un produit repurposé sont formulées. Intégrées au plus tôt, elles visent à faciliter la réutilisation des produits en tenant compte des parties-prenantes, des phases du cycle de vie, des aspects temporels et en gérant mieux l’information.Enfin, un cadre générique structurant la réalisation d’analyses du cycle de vie de ces solutions est proposé. Les ACVistes pourront ainsi plus facilement tenir compte des spécificités de ces stratégies, car la complexité des modélisations ACV pour les produits aux applications en cascade nécessite davantage de rigueur et de précision que pour des produits à application unique. Pour supporter ce cadre, trois recommandations à destination des équipes de conception sont émises. Elles permettent la formalisation d'éléments de contexte pour améliorer la comparaison avec d’autres études et d’informations en vue des analyses de sensibilité.Ces trois propositions sont implémentées sur deux cas d’étude ‘batterie’, au cours de séances de travail regroupant des parties-prenantes de l’ensemble du cycle de vie : commanditaire, équipes de conception, logisticiens, recycleur, etc
This PhD dissertation focuses on an innovative end-of-life strategy: repurposing. We define ‘repurposing’ as a manufacturing process through which products nearing their end-of-life are reused in different applications. At the end of their intended use, products are reintegrated into the manufacturing chain and adapted for their next application. We also refer to this strategy as cascading application reuse (CAR). The main purpose of CAR is the preservation of the added-value of such products. This strategy is in line with other reuse strategies such as direct reuse and remanufacturing.The central illustration in our case study addresses lithium-ion batteries used in electric vehicles, which are recycled when the battery’s charging capacity falls below 80%. Extending the component lifespan with a second application, e.g. stationary application, postpones introduction into the waste stream, retaining the added-value from the original manufacturing process. Despite these advantages, examples of product adaptation for CAR remain at a proof-of-concept scale - currently these products and their value chains are not yet designed with strategies supporting reuse.The objective of this research is to provide a clear vision to design teams about repurposing strategies, how to integrate the strategies during the upstream stages of the design process and how to facilitate the corresponding lifecycle assessment. The objective is to support designers during the manufacturing of repurposed products. We make three proposals.The first consists of classifying the characteristics specific to the repurposing strategy according to three axes: the product, the (re)manufacturing process and the business model. Through this framework, we describe the dimensions and characteristics of what the repurposed product offers, which are integral during the design activity. These attributes are the result of a study of the relevant literature coupled with several field investigations.Our second proposal concerns the design process for such products. Indeed, several differences with classical design practices appear: the need for product recovery at the end of use, subsequent applications and needs not fully defined, which affect performance, etc. A design stage for repurposed products must therefore be integrated before subsequent applications in order to optimise redesign solutions. Integrated as early as possible, they aim to facilitate product reuse by taking into account stakeholders, life cycle phases, time aspects and better information management.Finally, a generic framework structuring the carrying out of life cycle analyses of repurposing is proposed. This will simplify the inclusion of their specificities for life cycle assessments (LCA) practitioners. Indeed, the complexity of LCA modelling for cascading applications products requires more rigour and precision than single application products. To support this framework, three recommendations for design teams are made, the objective of which is to better formalise the information from the design process. These recommendations support the formalisation of contextual elements to improve comparison with other studies and the organisation of information for sensitivity analyses.These three proposals are implemented on two battery case studies, during working sessions involving stakeholders representing the complete life cycle: sponsor, design teams, logisticians, recycler, etc
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Bessard, Anne. "Mécanismes moléculaires de la cascade de signalisation des MAPKinases contrôlant la motilité et la prolifération des cellules hépatiques normales et transformées." Rennes 1, 2006. http://www.theses.fr/2006REN1S035.

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Ce travail est centré sur l'étude des mécanismes d'induction et de répression des signaux mitogènes et de motilité des hépatocytes. Le blocage de la prolifération et de la survie des cellules transformées représente un enjeu important dans le développement de traitement anti-cancéreux. Cet objectif, nous a conduit à : 1/ préciser l'implication de la voie MEK/ERK dans l'équilibre prolifération / motilité et démontrer l'incidence de MLCK dans l'intégration des signaux mitogènes dans les hépatocytes normaux ; 2/ analyser les mécanismes MEK/ERK dépendants, régulant la motilité et la prolifération des cellules issues d'hépatocarcinomes ; 3/ appréhender plusieurs techniques d'imagerie afin de visualiser au mieux la tumeur induite suite à l'injection de cellules cancéreuses en ectopique et en orthotopique. Toutes les informations obtenues à l'issue de ces différentes approches devraient nous permettre un meilleur suivi de la croissance tumorale in vivo et de définir de nouvelles cibles thérapeutiques.
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Joussot, Jessie. "Stratégies de synthèse d’un nouvel antipsychotique potentiel : cascades réactionnelles palladocatalysées : un outil puissant pour la synthèse de structures polycycliques complexes et hautement fonctionnalisées." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF016/document.

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Ces travaux de thèse ont permis dans un premier temps, d'aborder différentes voies de synthèse d'un nouvel antipsychotique potentiel (F17464) proposé par les laboratoires Pierre Fabre. Trois stratégies basées sur des synthèses convergentes ont été initiées. La première stratégie repose sur une étape clé de métathèse croisée, la seconde sur une réaction de Sonogashira et la troisième aborde une nouvelle méthodologie d'alkylation des chromones en position 3. Ces méthodes nous ont permis d'accéder à des intermédiaires de synthèse originaux, utiles pour préparer la molécule F17464 en respectant les contraintes industrielles.Dans un deuxième temps, différents types de molécules polycycliques complexes ont été synthétisés par cascades réactionnelles palladocatalysées. Une série de naphtalènes condensés a été préparée par réaction domino palladocatalysée issue de cyclocarbopalladations successives suivies d'une activation C(sp2)-H. Plusieurs types de cycles à sept atomes de carbone condensés ont été synthétisés en une seule étape, à partir de substrats faciles d'accès, via des cascades réactionnelles cyclocarbopalladations/activation C(sp2) ou C(sp3)-H.Finalement, des cyclooctatriènes et des fenestradiènes ont été obtenus à partir du même substrat,en une seule étape, via des réactions en cascade débutant par une cyclocarbopalladation 4-exodigsuivie d'un couplage de Stille puis d'une addition d'alcynes sur une triple liaison s'achevant par des réactions d'électrocyclisations. La température est le seul paramètre réactionnel qui diffère dans la synthèse de ces deux polycycles complexes, à partir du même substrat
This PhD thesis allowed us in the first part to develop different synthesic pathways to a new potential antipsychotic (F17464) invented by Pierre Fabre laboratories. Three strategies based on convergent syntheses are initiated. The key step of the first strategy is olefin cross metathesis. The second strategy rests on Sonogashira coupling and the third one involves a new methodology ofchromones alkylation in position 3. These methods allowed us access to novel synthetic intermediates, useful in the preparation of the F17464 molecule by following industrial confines.ln the second part, different types of polycyclic molecules were synthesized by palladium-catalyzed cascade reactions. A set of fused naphthalenes was prepared by palladium-catalyzed dominoreaction including cyclocarbopalladations followed by C(sp2)-H bond activation. Several types of fused seven-membered carbocycles were synthesized in a one-pot reaction from convenient substrates, via cascade reactions including cyclocarbopalladations followed by C(sp2 or sp3)-Hbond activation. Finally, cyclooctatrienes and fenestradienes were obtained also in a one-pot reaction from the same substrate via cascade reactions involving 4-exo-dig cyclocarbopalladation, followed by Stille coupling, alkyne addition onto a triple bond, finishing by electrocyclization reactions. Temperature is the only parameter that differs in the synthesis ôf the two complex polycycles starting from the same substrate
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Younes, Mourad. "Capture du CO2 par anti-sublimation : conception, simulation et réalisation d'un prototype." Paris, ENMP, 2003. http://www.theses.fr/2003ENMP1192.

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Les émissions du CO2 sont en hausse, provoquant vraisemblablement une augmentation de la température du Globe; ceci a conduit au Protocole de Kyoto qui vise à élaborer des politiques de limitation des émissions de gaz à effet de serre dont le CO2. De nombreuses options existent pour limiter les émissions de CO2 liées à la production d'énergie dont l'une fait l'objet de cette thèse, la capture du CO2 sur les fumées. Les techniques usuelles de capture du CO2 sont analysées assez rapidement. La plus grande partie du travail vise à élaborer cette nouvelle méthode de capture basée sur le givrage du CO2 à basse température. Le givrage du CO2 est accompli par un système frigorifique, dit en cascade intégrée, offrant des températures d'évaporation inférieures à la température de givrage du CO2. Plusieurs architectures sont étudiées afin de choisir celle qui apparaît la plus efficace énergétiquement. Une maquette prototype a été conçue et réalisée pour valider l'ensemble des concepts sur le givrage et le dégivrage du CO2. Le dimensionnement des composants a été réalisé à l'aide de modèles informatiques développés pour modéliser des cascades intégrées multi-étagées. Le système possède 2 évaporateurs basse température fonctionnant alternativement en givrage et dégivrage afin de permettre un fonctionnement continu du système. L'énergie "froide" du dégivrage est récupérée par le mélange de fluides frigorigènes, ce qui permet d'améliorer l'efficacité énergétique du système
Missions of CO2 are increasing, leading to temperature increase of Earth. This led to the Kyoto Protocol which aims at the elaboration of policies of limitation of the emissions of greenhouse gases among which CO2. A large number of options exist to limit CO2 emissions associated with energy production, one of them is developed in this dissertation, the CO2 capture from flue gases. Usual techniques of CO2 capture are briefly analyzed. The major part of this work concerns the development of a new CO2 capture based on the CO2 frosting at low temperature. The CO2 frosting is performed by a refrigerating system composed of an integrated cascade, which offers evaporating temperatures lower than the CO2 frosting temperature. Several architectures are analyzed in order to choose the most energy efficient one. A prototype mock-up has been designed and realized for the validation of the global concepts of the CO2 frosting and defrosting. The components have been sized using computerized tools developed for the modeling of multi-stage integrated cascades. The system includes two low-temperature evaporators operating alternatively in frosting and defrosting modes to permit continuous system operation. The "cold" energy from defrosting is recovered by the refrigerant blend, which permits to improve the energy efficiency of the system
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Douss, Néjib. "Etude experimentale de cycles a cascades a adsorption solide." Paris 7, 1988. http://www.theses.fr/1988PA077052.

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Etude experimentale et simulation dynamique de systemes de pompe a chaleur a adsorption solide. Les systemes methanol-charbon actif et eau-zeolite sont etudies. Les conditions de temperature des composants (adsorbeur, condenseur et evaporateur) doivent etre homogenes pour la simulation. On considere les cycles intermittents (simple effet), a double effet et a triple effet (cycle a cascades). Determination d'un coefficient de performance pour la production du froid
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Douss, Néjib. "Etude expérimentale de cycles à cascades à adsorption solide." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37613349g.

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Khůlová, Jitka. "Topné výměníky, vliv zapojení na účinnost cyklu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-400503.

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The master's thesis deals with district heat exchangers in a thermal steam cycle of combined heat and power plants and with types of condensate cascades in the multilevel heating systems. Calculation of the thermal efficiency of electricity generation is provided for the investigated thermal cycle, which was modified for three different types of cascades. Besides that, a comparison of useful electric power and electricity generation through one year period of working is made. A significant part of the work is devoted to the design of district heat exchangers, including the calculation of thermal power and heat transfer area. Main dimensions are proposed for each exchanger together with a basic drawing.
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Goloubev, Dmitri. "Kühlung eines resistiven HTSL-Kurzschlussstrombegrenzers mit einer Gemisch-Joule-Thomson-Kältemaschine." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1095838519812-78347.

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Die vorliegende Arbeit beschäftigt sich nach der Analyse und Optimierung der Stromzuführungen auf Flüssigstickstoff-Temperaturniveau, hauptsächlich mit der Untersuchung einer Gemisch-Stickstoff-Kaskade als Kälteversorgungssystem eines resistiven HTSL-Kurzschlussstrombegrenzers. Unter einem Kurzschlussstrombegrenzer versteht man einen veränderlichen elektrischen Widerstand, welcher, gegebenenfalls in Serie mit konventionellen, mechanischen Stromunterbrechern, direkt in den zu schützenden Stromkreis eingebaut ist. Als veränderlicher elektrischer Widerstand kann z.B. ein supraleitendes Element verwendet werden. Im normalen Betriebsfall setzt dieser dem fließenden Strom praktisch keinen Widerstand entgegen. Die Dimensionierung wird so gewählt, dass im Falle eines Überstroms ein rascher Übergang in den normalleitenden Zustand erfolgt. Durch den nun vorhandenen Widerstand wird der Stromfluss sehr effektiv begrenzt, bis beispielsweise nachgeschaltete mechanische Schutzeinrichtungen ansprechen. Sobald dies erfolgt ist, kann der Supraleiter regenerieren und in den Ausgangszustand zurückkehren. Die Verwendung von HTSL-Material als Supraleiter erscheint hier höchst vorteilhaft, da damit ein Arbeiten auf Flüssigstickstoff-Temperaturniveau erlaubt wird. Ein entscheidender Punkt für die erfolgreiche Einführung der HTSL-FCL ist die Bereitstellung einer geeigneten Kälteversorgung. Dies kann entweder durch regelmäßiges Nachfühlen mit flüssigem Stickstoff oder durch den Einsatz einer Kältemaschine zur Stickstoffrekondensation realisiert werden. Beim Einsatz einer Kältemaschine hat man einen von der Stickstoffnachlieferung unabhängigen Betrieb mit geschlossenem Kühlsystem. Die Energiedissipation in dem HTSL-Element selbst ist unter Normalbedingungen vernachlässigbar klein. Für die Auslegung des Kühlsystems ist von Bedeutung, dass der größte Teil der Wärmelast durch die metallischen Stromzuführungen verursacht wird. Die Auslegung des Kühlsystems muss sich daher an der thermodynamischen Analyse der Stromzuführungen orientieren. Das Ziel dieser Arbeit bestand in der Analyse von Kühlmethoden für solche Stromzuführungen hinsichtlich ihrer Effektivität und Wirtschaftlichkeit. Ein neues Kühlsystem auf der Basis einer Gemisch-Stickstoff-Kaskade wird vorgeschlagen als Alternative zu den derzeit in Frage kommenden Kühltechniken. Es wurde folgende Vorgehensweise gewählt: 1. Verschiedene Kühlmethoden zur Kühlung von SZF werden aufgeführt und thermodynamisch bewertet. 2. Kühlsysteme, basierend auf einer Gemisch-Stickstoff-Kaskade, werden vorgeschlagen und deren Charakteristika mittels numerischer Simulation bestimmt. 3. Ein auf der Basis einer Gemisch-Kältemaschine gebauter Stickstoffverflüssiger wird in Betrieb genommen und getestet. 4. Die Funktion und die Effektivität der Gemisch-Stickstoff-Kaskade zur Kühlung der Stromzuführungen werden bewertet. 5. Zugehörige Kühlsysteme auf der Basis verschiedener Kühltechniken werden analysiert 6. In einer Wirtschaftlichkeitsbetrachtung werden die Kühlsysteme einander gegenübergestellt Insgesamt kann als Ergebnis festgehalten werden, dass der Einsatz der vorgestellten Gemisch-Stickstoff-Kaskadenanlagen zur Kälteversorgung im vorgestellten Anwendungsfall eine durchaus wettbewerbsfähige, voraussichtlich sogar überlegene Alternative zu den sonst verfügbaren Methoden darstellt.
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Brown, Ashlie M. "Improved thermal energy utilization through coupled and cascaded cooling cycles." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31645.

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Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2010.
Committee Chair: Dr. Srinivas Garimella; Committee Member: Dr. Samuel Graham; Committee Member: Dr. Sheldon Jeter. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Books on the topic "CASCADE CYCLE"

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Pehlken, Alexandra, Matthias Kalverkamp, and Rikka Wittstock. Cascade Use in Technologies 2018: Internationale Konferenz zur Kaskadennutzung und Kreislaufwirtschaft – Oldenburg 2018. Springer Vieweg, 2018.

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Jacobsen, Dean, and Olivier Dangles. Energy flow and species interactions at the edge. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198736868.003.0007.

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Chapter 7 elucidates the relationships between the structure and functioning of aquatic ecosystems at high altitude through the description of material cycles and food webs. Following the landscape continuum model, material cycling is profoundly influenced by the physical structure of the waterscape (e.g. vegetation cover); as a result a great diversity of energetic pathways characterize high altitude waterscapes, along an autotrophy–heterotrophy gradient. Similarly, high altitude aquatic food webs embrace a great diversity of trophic compartments, feeding strategies, and processes (trophic cascades and terrestrial subsidiarity) that are profoundly shaped by environmental harshness. Harsh conditions also generate stress gradients along which the strength and direction of species interactions (from competition to facilitation) and their functional role (e.g. as ecosystem engineers) are modified. The resulting structural and functional changes affect in turn species coexistence and trigger potential ecosystem shifts.
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Book chapters on the topic "CASCADE CYCLE"

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Kalverkamp, Matthias, and Neele Karbe. "Comparability of Life Cycle Assessments: Modelling and Analyzing LCA Using Different Databases." In Cascade Use in Technologies 2018, 51–63. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-662-57886-5_8.

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Chabre, Marc, Bruno Antonny, and T. Minh Vuong. "The Transducin Cycle in the Phototransduction Cascade." In Biological Signal Transduction, 207–20. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-75136-3_15.

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Wulf, Kalle, Frauke Germer, and Henning Albers. "Comparison of Cascaded Utilization with Life Cycle Assessment – a Case Study of Wind Turbine Blades." In Cascade Use in Technologies 2018, 133–41. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-662-57886-5_16.

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Jonna, Gnaneswara Rao, Vamana Murthi Thuniki, and Madhu Mutyam. "CASCADE: Congestion Aware Switchable Cycle Adaptive Deflection Router." In Architecture of Computing Systems – ARCS 2016, 35–47. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30695-7_3.

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Bauer, Richard, J. David Christopher, Volker Glaab, Svetlana A. Lyapustina, Jolyon P. Mitchell, and Terrence P. Tougas. "Product Life Cycle Approach to Cascade Impaction Measurements." In Good Cascade Impactor Practices, AIM and EDA for Orally Inhaled Products, 135–49. Boston, MA: Springer US, 2013. http://dx.doi.org/10.1007/978-1-4614-6296-5_6.

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Gotoh, Yukiko, and Eisuke Nishida. "The MAP kinase cascade: Its role in Xenopus oocytes, eggs and embryos." In Progress in Cell Cycle Research, 287–97. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4615-1809-9_23.

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Dao, Thi-Kien, Trong-The Nguyen, The-Vinh Do, Trinh-Dong Nguyen, and Vinh-Tiep Nguyen. "An Optimal Cascade Reservoir Operation Based on Multi-objective Water Cycle Algorithm." In Advances in Engineering Research and Application, 188–200. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-22200-9_20.

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Kumar, Sachin, and Virender Chahal. "A Review of Various Kinds of Cascade Refrigeration Cycle and Application of Ejector Mechanism." In Advances in Materials and Mechanical Engineering, 245–65. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-0673-1_20.

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Cao, Y., M. Q. Gong, Y. F. Qi, E. C. Luo, J. F. Wu, and G. M. Chen. "Thermodynamic Prediction of the Vortex Tube Applied to a Mixed-Refrigerant Auto-Cascade J-T Cycle." In Cryocoolers 12, 621–26. Boston, MA: Springer US, 2003. http://dx.doi.org/10.1007/0-306-47919-2_82.

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Ford, Heide L., Robert A. Sclafani, and James Degregori. "Cell Cycle Regulatory Cascades." In Cell Cycle and Growth Control, 93–128. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2004. http://dx.doi.org/10.1002/0471656437.ch3.

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Conference papers on the topic "CASCADE CYCLE"

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Beck, M., D. Hofstetter, T. Aellen, J. Faist, U. Oesterle, E. Gini, and H. Melchior. "Quantum cascade laser operation with high duty cycle." In CLEO 2001. Technical Digest. Summaries of papers presented at the Conference on Lasers and Electro-Optics. Postconference Technical Digest. IEEE, 2001. http://dx.doi.org/10.1109/cleo.2001.947868.

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Kilicarslan, Ali, and Norbert Mu¨ller. "Irreversibility Analysis of a Vapor Compression Cascade Refrigeration Cycle." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-66363.

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Hydrocarbon based energy sources such as coal, oil and natural gas have been diminishing in an increasing speed. Instead of finding alternative energy sources, we have to use the available sources more effectively. By means of the irreversibility analysis, we can determine the factors or conditions that cause the inefficiencies in any energy system. In this study, irreversibility analysis of a compression cascade refrigeration cycle that consists of a high and low temperature cycles is presented. In the high temperature cycle, the refrigerants from different classes, namely R12 (CFC), R22 (HCFC), R134a (HFC) and R404a (Azeotropic) are selected as working fluids. In the low temperature cycle, R13 is only used as a working fluid. Irreversibility analysis of refrigerant pairs, namely R12-R13, R22-R13, R134a-R13, and R404a-R13 are carried out in a compression cascade refrigeration cycle by a computer code developed. The effects of evaporator temperature, condenser temperature, and the temperature difference between the saturation temperatures of the lower and higher temperature cycles in the heat exchanger (ΔT) and the polytropic efficiency on irreversibility of the system are investigated. The irreversibility of the cascade refrigeration cycle decreases as the evaporator temperature and polytropic efficiency increase for all of the refrigerant couples considered while the irreversibility increases with the increasing values of the condenser temperature and ΔT. In the whole ranges of evaporator temperature (−65°C / −45°C), condenser temperature (30–50°C), ΔT (2–16K) and polytropic efficiency (%50/%100), the refrigerant pair R12-R13 has the lowest values of irreversibilities while the pair R404a-R13 has the highest ones. At the lower condenser temperature (<30°C) and higher polytropic efficiencies (85%–95%), the refrigerant couples except for R404a-R13 have approximately the same values of irreversibility.
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Xie, Yingbai, Kuikui Cui, Luxiang Zong, and Zhichao Wang. "The Entropy Analysis on NH3/CO2 Cascade Refrigeration Cycle." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-40121.

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This paper introduces a cascade refrigeration cycle that uses natural refrigerants of CO2 and NH3 at low temperature. It introduces the character of CO2 and NH3, besides analyzes the cascade refrigeration cycle. The optimal intermediate temperature of NH3/CO2 cascade refrigeration cycle is determined by the entropy production minimization method. We analyze the four processes entropy production in both CO2 cycle (LT side) and NH3 cycle (HT side) and research how the total entropy production changes in the conditions of different T0, different TCL and different ΔT. We also find that in order to enhance the efficiency of NH3/CO2 cascade refrigeration cycle, it is necessary to reduce ΔT. It can be concluded that NH3/CO2 cascade refrigeration cycle has a good future.
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Araújo, Hugo. "Exergy analysis of a natural gas liquefaction cascade cycle." In 16th Brazilian Congress of Thermal Sciences and Engineering. ABCM, 2016. http://dx.doi.org/10.26678/abcm.encit2016.cit2016-0646.

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Fasching, G., A. Benz, J. Kroll, J. Darmo, Ch Deutsch, A. M. Andrews, W. Schrenk, G. Strasser, and K. Unterrainer. "From few-cycle THz pulses to terahertz quantum-cascade lasers." In 2007 19th International Conference on Applied Electromagnetics and Communications (ICECom). IEEE, 2007. http://dx.doi.org/10.1109/icecom.2007.4544436.

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Georgiou, Demos P. "The Travelling Cascade, Constant Volume Heat Exchanger in a Gas Turbine Lead Combined Cycle." In ASME 1996 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-gt-536.

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When a gas enclosed in a cavity is heated or cooled, its pressure changes with its temperature as well. If a set of two countermoving “driven” cavity cascades employs the same free wall, then the system will operate as a countercurrent heat exchanger. At the exit points of the heat exchanger the two gases can be brought back to their original (atmospheric) pressure by isentropic processes thus producing useful work. The entire set of thermodynamic processes forms a double Lenoir cycle. The exhausts from the two Lenoir cycles may drive two more sets of corresponding cycles, thus allowing for the cascading of the process, until the added useful work becomes insignificant. When this idea is employed as a bottoming cycle in a Gas Turbine lead Combined cycle, employing four sets of Lenoir cycles, the achievable total thermal efficiencies rise to the 75 to 82 % level, athough the amount of heat transferred in all these processes is about 50 % more than that in a modern Brayton-Rankine combined cycle.
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Schroder, Andy, Mark G. Turner, and Rory A. Roberts. "Combined Cycle Engine Cascades Achieving High Efficiency." In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-58004.

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Two combined cycle engine cascade concepts are presented in this paper. The first uses a traditional open loop gas turbine engine (Brayton cycle) with a combustor as the topping cycle and a series of supercritical carbon dioxide (S–CO2) engines as intermediate cycles and a bottoming cycle. A global optimization of the engine design parameters was conducted to maximize the combined efficiency of all of the engines. A combined cycle efficiency of 65.0% is predicted. The second combined cycle configuration utilizes a fuel cell inside of the topping cycle in addition to a combustor. The fuel cell utilizes methane fuel. The waste heat from the fuel cell is used to heat the high pressure air. A combustor is also used to burn the excess fuel not usable by the fuel cell. After being heated, the high pressure, high temperature air expands through a turbine to atmospheric pressure. The low pressure, intermediate temperature exhaust air is then used to power a cascade of supercritical carbon dioxide engines. A combined efficiency of 73.1% using the fuel lower heating value is predicted with this combined fuel cell and heat engine device. Details of thermodynamics as well as the (S–CO2) engines are given.
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Ouyang, Shaodi, Jinjun Liu, Xinyu Wang, and Fei Meng. "One-cycle control of a delta-connected cascade H bridge rectifier." In 2014 IEEE International Power Electronics and Application Conference and Exposition (PEAC). IEEE, 2014. http://dx.doi.org/10.1109/peac.2014.7037973.

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Riepl, J., J. Raab, P. Abajyan, H. Nong, J. R. Freeman, L. H. Li, E. H. Linfield, et al. "Sub-cycle high-order nonlinearities in a terahertz quantum cascade laser." In 2022 47th International Conference on Infrared, Millimeter and Terahertz Waves (IRMMW-THz). IEEE, 2022. http://dx.doi.org/10.1109/irmmw-thz50927.2022.9895597.

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Purushothaman, Kirubakaran, Sankar Kumar Jeyaraman, Sasikanta Parida, and Kishore Prasad Deshkulkarni. "Aeroelastic Flutter Analysis of Linear Cascade Blades: STC5." In ASME 2017 Gas Turbine India Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gtindia2017-4773.

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Study of aerodynamic flow and aeroelastic stability in vibrating blades of cascade is the main objective of this study. Standard test configuration (STC-5) was chosen for this study as it involves transonic flow regime in compressor blade cascades. CFD analysis were carried out for 11 test cases of STC-5 configuration and pressure coefficient values were compared with test data. The range of incidence angles vary from 2° to 10° and reduced frequency varies from 0.14 to 1.02. Inflow Mach number was fixed at 0.5 and Reynolds number was fixed at 1.4 × 106. Analysis of vibrating blades and comparison of test data results of axial compressor with linear cascade stator blades of fifth standard configuration at high subsonic speed is compared with CFD results. While doing this vibration of only the center blade is concerned when all the other blades in the cascade are fixed. Fluid structure interaction approach is used here to evaluate the unsteady aerodynamic force and work done for a vibrating blade in CFD domain. Energy method and work per cycle approach is adapted for aerodynamic damping prediction. A framework has been developed to estimate the work per cycle and aerodynamic damping ratio. Final sensitivity study was carried out to evaluate the influence of blade incidence and frequency on blade damping values.
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Reports on the topic "CASCADE CYCLE"

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Delwiche, Michael, Boaz Zion, Robert BonDurant, Judith Rishpon, Ephraim Maltz, and Miriam Rosenberg. Biosensors for On-Line Measurement of Reproductive Hormones and Milk Proteins to Improve Dairy Herd Management. United States Department of Agriculture, February 2001. http://dx.doi.org/10.32747/2001.7573998.bard.

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The original objectives of this research project were to: (1) develop immunoassays, photometric sensors, and electrochemical sensors for real-time measurement of progesterone and estradiol in milk, (2) develop biosensors for measurement of caseins in milk, and (3) integrate and adapt these sensor technologies to create an automated electronic sensing system for operation in dairy parlors during milking. The overall direction of research was not changed, although the work was expanded to include other milk components such as urea and lactose. A second generation biosensor for on-line measurement of bovine progesterone was designed and tested. Anti-progesterone antibody was coated on small disks of nitrocellulose membrane, which were inserted in the reaction chamber prior to testing, and a real-time assay was developed. The biosensor was designed using micropumps and valves under computer control, and assayed fluid volumes on the order of 1 ml. An automated sampler was designed to draw a test volume of milk from the long milk tube using a 4-way pinch valve. The system could execute a measurement cycle in about 10 min. Progesterone could be measured at concentrations low enough to distinguish luteal-phase from follicular-phase cows. The potential of the sensor to detect actual ovulatory events was compared with standard methods of estrus detection, including human observation and an activity monitor. The biosensor correctly identified all ovulatory events during its testperiod, but the variability at low progesterone concentrations triggered some false positives. Direct on-line measurement and intelligent interpretation of reproductive hormone profiles offers the potential for substantial improvement in reproductive management. A simple potentiometric method for measurement of milk protein was developed and tested. The method was based on the fact that proteins bind iodine. When proteins are added to a solution of the redox couple iodine/iodide (I-I2), the concentration of free iodine is changed and, as a consequence, the potential between two electrodes immersed in the solution is changed. The method worked well with analytical casein solutions and accurately measured concentrations of analytical caseins added to fresh milk. When tested with actual milk samples, the correlation between the sensor readings and the reference lab results (of both total proteins and casein content) was inferior to that of analytical casein. A number of different technologies were explored for the analysis of milk urea, and a manometric technique was selected for the final design. In the new sensor, urea in the sample was hydrolyzed to ammonium and carbonate by the enzyme urease, and subsequent shaking of the sample with citric acid in a sealed cell allowed urea to be estimated as a change in partial pressure of carbon dioxide. The pressure change in the cell was measured with a miniature piezoresistive pressure sensor, and effects of background dissolved gases and vapor pressures were corrected for by repeating the measurement of pressure developed in the sample without the addition of urease. Results were accurate in the physiological range of milk, the assay was faster than the typical milking period, and no toxic reagents were required. A sampling device was designed and built to passively draw milk from the long milk tube in the parlor. An electrochemical sensor for lactose was developed starting with a three-cascaded-enzyme sensor, evolving into two enzymes and CO2[Fe (CN)6] as a mediator, and then into a microflow injection system using poly-osmium modified screen-printed electrodes. The sensor was designed to serve multiple milking positions, using a manifold valve, a sampling valve, and two pumps. Disposable screen-printed electrodes with enzymatic membranes were used. The sensor was optimized for electrode coating components, flow rate, pH, and sample size, and the results correlated well (r2= 0.967) with known lactose concentrations.
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