Relevant bibliographies by topics / Equilibrium composition of the environment

Academic literature on the topic 'Equilibrium composition of the environment'

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Published: 30 May 2022
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Journal articles on the topic "Equilibrium composition of the environment"

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GLADYSHEV, G. P., D. KH KITAEVA, and E. N. OVCHARENKO. "WHY DOES THE CHEMICAL COMPOSITION OF LIVING THINGS ADAPT TO THE ENVIRONMENT?" Journal of Biological Systems 04, no. 04 (December 1996): 555–64. http://dx.doi.org/10.1142/s0218339096000351.

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It is shown, using the example of fatty acids contained in living things, that the temperature adaptation of the living things chemical composition is a consequence of the second principle of thermodynamics in its classical form. The obtained result is interesting since the application of equilibrium thermodynamics to living organisms was being rejected for a long time because of the complexity and open nature of these organisms.
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Ibañez-Mejia, Mauricio, and François L. H. Tissot. "Extreme Zr stable isotope fractionation during magmatic fractional crystallization." Science Advances 5, no. 12 (December 2019): eaax8648. http://dx.doi.org/10.1126/sciadv.aax8648.

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Zirconium is a commonly used elemental tracer of silicate differentiation, yet its stable isotope systematics remain poorly known. Accessory phases rich in Zr4+ such as zircon and baddeleyite may preserve a unique record of Zr isotope behavior in magmatic environments, acting both as potential drivers of isotopic fractionation and recorders of melt compositional evolution. To test this potential, we measured the stable Zr isotope composition of 70 single zircon and baddeleyite crystals from a well-characterized gabbroic igneous cumulate. We show that (i) closed-system magmatic crystallization can fractionate Zr stable isotopes at the >0.5% level, and (ii) zircon and baddeleyite are isotopically heavy relative to the melt from which they crystallize, thus driving chemically differentiated liquids toward isotopically light compositions. Because these effects are contrary to first-order expectations based on mineral-melt bonding environment differences, Zr stable isotope fractionation during zircon crystallization may not solely be a result of closed-system thermodynamic equilibrium.
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Novikov, Dmitry A. "Chemical equilibrium of groundwater with minerals of the host rocks in Upper Jurassic sediments (Arctic regions of Western Siberia)." E3S Web of Conferences 98 (2019): 01037. http://dx.doi.org/10.1051/e3sconf/20199801037.

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The results of thermodynamic calculations for a water-rock system in the Upper Jurassic deposits of the Arctic regions of Western Siberia are presented. In the area under investigation the groundwaters have been identified with mineralization up to 63.3 g/L and various chemical composition and genesis. Despite the long interaction with the rock (150-160 ma) equilibrium with endogenous minerals (albite, microcline and anorthite) is practically not observed. At the same time, groundwaters are in equilibrium with clay minerals and micas, such as: Caand Na-montmorillonites, kaolinite, paragonite, margarite, illite, muscovite and Mg-chlorite. The establishment of a balance of groundwater with primary aluminosilicate minerals is also affected by interactions with carbonate minerals. The differences in composition of groundwater in equilibrium with certain aluminosilicates and carbonates indicate that the mineral changes are formed from a solution of a strictly defined chemical composition in an appropriate geochemical environment.
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Yamamoto, Tetsuo. "Chemical Composition of Dust Expected from Condensation Models." International Astronomical Union Colloquium 126 (1991): 413–20. http://dx.doi.org/10.1017/s025292110006721x.

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AbstractThis review examines to what degrees the present chemical equilibrium condensation models are effective in predicting chemical composition of grains observed in a variety of cosmic environments. The composition expected from the equilibrium calculations is reviewed separately for refractory (rocky and metallic) and volatile (icy) components. Comments are given on the limitation of the equilibrium calculations in predicting the grain composition. By taking cometary ice as a typical cosmic volatile condensate, it is pointed out that its composition is far from that expected from the equilibrium models. Theories on the formation of cometary volatiles are reviewed, and an observational clue helpful to testing the theories is pointed out. Discussion is given on the advantage for formation of organic materials from volatile solids.
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Novikov, D. A. "CATAGENETIC ALTERATION HYDROGEOCHEMISTRY OF SEDIMENTARY ROCKS OF HYDROCARBON OCCURRENCES IN ARCTIC AREASOF THE WESTERN SIBERIAN MEGABASIN." Oil and Gas Studies, no. 6 (December 1, 2016): 19–25. http://dx.doi.org/10.31660/0445-0108-2016-6-19-25.

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For the first time a detailed analysis of the equilibrium-non-equilibrium state of ground waters of hydrocarbon occurrences in Arctic areas of the West Siberian megabasin based on physico-chemical modeling of equilibria in the «water-rock» revealed hydrogeochemical and thermodynamic conditions for the formation of authigenic minerals. For the first time equilibrated compositions of groundwaters and parameters of geochemical environment were identified, being a prerequisite for the mineral neoformations.
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Dřímal, Pavel, Josef Hrnčiřík, and Jaromír Hoffmann. "Assessing Aerobic Biodegradability of Plastics in Aqueous Environment by GC-Analyzing Composition of Equilibrium Gaseous Phase." Journal of Polymers and the Environment 14, no. 3 (August 25, 2006): 309–16. http://dx.doi.org/10.1007/s10924-006-0024-5.

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Cusack, Maggie, David Parkinson, Alberto Pérez-Huerta, Jennifer England, Gordon B. Curry, and Anthony E. Fallick. "Relationship between δ18O and minor element composition of Terebratalia transversa." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 98, no. 3-4 (September 2007): 443–49. http://dx.doi.org/10.1017/s1755691008075671.

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ABSTRACTWith their extensive fossil record and shells of stable low-Mg calcite, rhynchonelliform brachiopods are attractive sources of climate information via seawater temperature proxies such as stable oxygen isotope composition. In Terebratalia transversa (Sowerby) there is a progression towards oxygen isotope equilibrium in the calcite of the innermost secondary layer. This study confirms the lack of any vital effects influencing oxygen isotope composition of T. transversa, even in specialised areas of the innermost secondary layer. Calcite Mg/Ca ratio is another potential seawater temperature proxy, that has the advantage of not being influenced by salinity. Mg concentrations measured by electron microprobe analyses indicate that there is no concomitant decrease in Mg concentration towards the inner secondary layer, associated with the progressive shift towards oxygen isotope equilibrium. Mg distribution is heterogeneous throughout the shell and correlates with that of sulphur, which may be a proxy for organic components, suggesting that some of the Mg may not be in the calcite lattice. It is essential therefore, to determine the chemical environment of the magnesium ions to avoid any erroneous temperature extrapolations in brachiopods or any other calcite biomineral.
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Filatov, E. S. "Investigations of the corrosion activity of the KAlCl4 melts by the methods of physicochemical analysis." Practice of Anticorrosive Protection 24, no. 4 (December 1, 2019): 59–66. http://dx.doi.org/10.31615/j.corros.prot.2019.94.4-7.

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Corrosion behavior of metal alloys in a melt of potassium chloroaluminate (KAlCl4) was investigated. Metal aluminum was used as a protector for protection against continuous frontal corrosion. The equilibrium potentials of aluminum and the corrosion potential of the alloys were measured. The data were obtained to evaluate the corrosion ability of the system of molten salt of potassium chloroaluminate - gas (argon) by measuring the redox potential of the specified environment depending on the composition of the gas atmosphere above it, i.e. from impurities of water vapor, hydrochloric acid, oxygen and other, for example, carbonaceous gases. The calculations of the protection efficiency using the potential difference between the metal aluminum and the protected material were performed. The regularities of changes in the equilibrium potentials of aluminum from the temperature and concentration were established as the fundamental data for possible use at determining the composition ratio of potassium chlorides and aluminum in potassium chloroaluminate as input data for the development of a sensor of composition of chloroaluminate potassium.
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Boivin, Edouard, Jean-Noël Chotard, Michel Ménétrier, Lydie Bourgeois, Tahya Bamine, Dany Carlier, François Fauth, Emmanuelle Suard, Christian Masquelier, and Laurence Croguennec. "Structural and electrochemical studies of a new Tavorite composition: LiVPO4OH." Journal of Materials Chemistry A 4, no. 28 (2016): 11030–45. http://dx.doi.org/10.1039/c6ta03339c.

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A vanadium based hydroxy-phosphate of the Tavorite-type structure LiVPO4OH was obtained for the first time, by a hydrothermal route. Li+ and H+ are extracted from the structure at the same equilibrium potential.
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Fedorenkova, L. "Formation of Hydrides in the Surface Layer of Aluminum in NonEquilibrium Conditions of Electrolyte Plasma." Фізика і хімія твердого тіла 20, no. 2 (July 10, 2019): 181–84. http://dx.doi.org/10.15330/pcss.20.2.181-184.

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In this paper, the formation of a diffusion layer on aluminum, which includes aluminum hydrides, in non-equilibrium conditions of electrolyte plasma with high local temperatures, high heating and cooling rates were studied. As a result of the research it was obtained that in the diffusion layer formed complex nanosized inclusions of polymorphic modifications (AlН3)n and AlB3H12. The diffusion in the non-equilibrium conditions of the electrolyte plasma is carried out in hydrogen environment, where the hydrogen atoms have the greatest energy and is one of the main forces that activate the diffusion process and influence the structure, composition and micromechanical characteristics of the diffusion layer.
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Dissertations / Theses on the topic "Equilibrium composition of the environment"

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Гончар, Кирило Романович. "Високотемпературна нітроцементація цирконію." Bachelor's thesis, КПІ ім. Ігоря Сікорського, 2019. https://ela.kpi.ua/handle/123456789/28151.

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В роботі досліджено можливість одночасного насичення цирконію в продуктах розкладу оксалату амонію. Теоретично розраховано та експе-риментально підтверджено співвідношення компонентів рівноважного складу реакційного середовища для нанесення комплексних покриттів методом дифузійного насичення азотом, вуглецем та киснем за участю водню. Склад як газової так і конденсованої фази залежить від складу та співвідношення реа-гентів в насичуючій суміші; Формування комплексних покрит-тів на основі сполук цирконію ZrN, ZrO2, та ZrС з високою твердістю та добрим зчепленням з ос-новою можна вважати позитивним досягненням даного дослідження. Такі покриття можуть бути перспе-ктивними при використанні в медичній, хімічній промисловості та атомній енергетиці.
In this work the possibility of simul-taneous saturation of zirconium in products of decomposition of am-monium oxalate has been investigat-ed. The ratio of components of the equi-librium composition of the reaction medium to the application of com-plex coatings by diffusion saturation with nitrogen, carbon and oxygen with the participation of hydrogen has been theoretically calculated and experimentally confirmed. The com-position of both the gas and the con-densed phase depends on the com-position and ratio of reagents in the saturated mixture . Calculated reaction formation nitride ZrN, oxide ZrO2, zirconium carbide ZrC with hydrogen and the reaction between each of nitrogen, oxygen, carbon and hydrogen. Thermody-namic probability of formation of carbides, nitrides and oxides decreas-es with increasing temperature;
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Pötzelberger, Klaus, and Leopold Sögner. "Equilibrium and learning in a non-stationary environment." SFB Adaptive Information Systems and Modelling in Economics and Management Science, WU Vienna University of Economics and Business, 2001. http://epub.wu.ac.at/1708/1/document.pdf.

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This article considers three standard asset pricing models with adaptive agents and stochastic non-stationary dividends. We assume that the parameters are estimated by exponential smoothing, such that prices and returns remain random variables. This paper provides sufficient conditions for the ergodicity of the return process and checks whether the perceived law assumed by the bounded rational agents can be considered to be sound with the returns observed. (author's abstract)
Series: Report Series SFB "Adaptive Information Systems and Modelling in Economics and Management Science"
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HUANG, Cuiting. "Service composition in converged service environment." Phd thesis, Institut National des Télécommunications, 2012. http://tel.archives-ouvertes.fr/tel-00762644.

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The goal of this thesis is to provide enhanced mechanisms to deploy competitive services in a rapid and cost-effective manner. To achieve this goal, we first propose an automatic service composition model relying on an IMS/Web converged environment. This service composition model is intended to be one in which even non-professional users can easily reuse existing services to create new services. To further improve the automatic service composition feature, three strategies including passive update, active update and hybrid update are proposed and analyzed. We then propose a centralized service exposure framework for a variey of services, including Telecom / Web / Device / user-generated services. This framework aims at enhancing the user-centric and convergence features, and providing the unified access to diverse services.Subsequently, two P2P based service information sharing models are designed to complement the centralized service exposure model : i) A hierarchical P2P based model, which reuses Chord for guaranteeing the service discovery efficiency, meanwhile adopts the concept of abstract service publication and discovery for enabling the ambiguous services searching. ii) A triplex P2P overlay based model, which mainly targets the devices offered services. In this model, we use the gateways to delegate the devices residing in them for the global service exposure, and use a triplex overlay based architecture, which includes an underlying unstructured P2P layer, a Semantic Overlay Network (SON) based overlay and a service dependency overlay, for the service information sharing and discovery
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Huang, Cuiting. "Service composition in converged service environment." Thesis, Evry, Institut national des télécommunications, 2012. http://www.theses.fr/2012TELE0009/document.

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L'objectif de cette thèse est de fournir des mécanismes améliorés pour déployer des services compétitifs par des manières rapides et rentables. Nous proposons un modèle de composition de service basé sur un environnement IMS/Web convergent. Ce modèle permet aux utilisateurs non professionnels de réutiliser les services existants pour créer de nouveaux services facilement. Pour améliorer la fonctionnalité de composition automatique, trois stratégies, y compris mise à jour passive, mise à jour active et mise à jour hybride sont proposées et analysées. Nous introduisons ensuite une plateforme centralisée d'exposition de service pour une variété de services, y compris services de Télécom / Web / appareil / services générés par les utilisateurs. Cette plateforme vise à renforcer les caractéristiques de centrée-sur-utilisateur et convergence, et fournir l'accès unifié à différents services. Par la suite, deux modèles basés sur le P2P sont conçus pour compléter le modèle centralisé: i) Un modèle hiérarchique basé sur Chord pour garantir l'efficacité de la découverte de services. Il adopte le concept de publication et découverte de service abstrait pour permettre à la recherche de service ambiguë. ii) Un modèle de superposition-triplex et P2P basé, qui cible principalement des services offerts par les appareils. Dans ce modèle, nous utilisons des passerelles pour déléguer des appareils résidant en eux pour l'exposition globale de services, et utilisons une architecture basée sur une superposition triplex, qui comprend une couche P2P non structurée, une couche de réseau sémantique (SON), et une couche de dépendance de service, pour la partage de l'information de service et la découverte de services
The goal of this thesis is to provide enhanced mechanisms to deploy competitive services in a rapid and cost-effective manner. To achieve this goal, we first propose an automatic service composition model relying on an IMS/Web converged environment. This service composition model is intended to be one in which even non-professional users can easily reuse existing services to create new services. To further improve the automatic service composition feature, three strategies including passive update, active update and hybrid update are proposed and analyzed. We then propose a centralized service exposure framework for a variey of services, including Telecom / Web / Device / user-generated services. This framework aims at enhancing the user-centric and convergence features, and providing the unified access to diverse services.Subsequently, two P2P based service information sharing models are designed to complement the centralized service exposure model : i) A hierarchical P2P based model, which reuses Chord for guaranteeing the service discovery efficiency, meanwhile adopts the concept of abstract service publication and discovery for enabling the ambiguous services searching. ii) A triplex P2P overlay based model, which mainly targets the devices offered services. In this model, we use the gateways to delegate the devices residing in them for the global service exposure, and use a triplex overlay based architecture, which includes an underlying unstructured P2P layer, a Semantic Overlay Network (SON) based overlay and a service dependency overlay, for the service information sharing and discovery
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Hajji, Wajdi. "Dynamic service chain composition in virtualised environment." Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/36076.

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Network Function Virtualisation (NFV) has contributed to improving the flexibility of network service provisioning and reducing the time to market of new services. NFV leverages the virtualisation technology to decouple the software implementation of network appliances from the physical devices on which they run. However, with the emergence of this paradigm, providing data centre applications with an adequate network performance becomes challenging. For instance, virtualised environments cause network congestion, decrease the throughput and hurt the end user experience. Moreover, applications usually communicate through multiple sequences of virtual network functions (VNFs), aka service chains, for policy enforcement and performance and security enhancement, which increases the management complexity at to the network level. To address this problematic situation, existing studies have proposed high-level approaches of VNFs chaining and placement that improve service chain performance. They consider the VNFs as homogenous entities regardless of their specific characteristics. They have overlooked their distinct behaviour toward the traffic load and how their underpinning implementation can intervene in defining resource usage. Our research aims at filling this gap by finding out particular patterns on production and widely used VNFs. And proposing a categorisation that helps in reducing network latency at the chains. Based on experimental evaluation, we have classified firewalls, NAT, IDS/IPS, Flow monitors into I/O- and CPU-bound functions. The former category is mainly sensitive to the throughput, in packets per second, while the performance of the latter is primarily affected by the network bandwidth, in bits per second. By doing so, we correlate the VNF category with the traversing traffic characteristics and this will dictate how the service chains would be composed. We propose a heuristic called Natif, for a VNF-Aware VNF insTantIation and traFfic distribution scheme, to reconcile the discrepancy in VNF requirements based on the category they belong to and to eventually reduce network latency. We have deployed Natif in an OpenStack-based environment and have compared it to a network-aware VNF composition approach. Our results show a decrease in latency by around 188% on average without sacrificing the throughput.
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Blakstad, Eirik. "City Guide: Service Composition in an Urban Environment." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9916.

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The aim of this thesis has been to develop and validate the user interface of a service composition tool for creating mobile tourist services in a city environment. The project has been conducted in cooperation with SINTEF and the Norwegian research project UbiCompForAll. As part of this thesis, a number of scenarios were created initially, showing what kind of functionalities accessed using mobile devices might be useful for tourists in the city. Based on these scenarios, the graphical user interface of a composition service tool was created and then assessed through the involvement of several users using a paper prototyping approach. The results from the paper prototyping assessment showed that the proposed interface is generally easy to understand and use, although there were a number of improvements necessary in the areas of information abstraction, module naming and letting users be able to see the final product of the composition. In addition, as part of the assessment of the proposed interface, the realizability of the services specified using this interface was evaluated. An architecture for the service derived from the specification developed by the user was defined. This enabled us to check that all the information necessary for creating the composed services can be provided when using the proposed user interface.

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Pasztor, Egon 1975. "A graphical environment for gestural computer-aided composition." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/62375.

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Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2002.
Includes bibliographical references (leaves 102-103).
I have designed and implemented a software environment, a Windows application called Hyperscore, that presents a novel, easy-to-learn interface for composing richly textured music through line gestures. The program allows the user to command a set of music-manipulation algorithms written by Mary Farbood [Farbood, 2001]. The interface is both compelling and interesting for musically untrained users, and rich enough that such users, after sufficient practice, can create music that professional musicians find to be of high quality. While many musical composition programs geared for musically untrained users exist, it is its unique user interface, its use of freely drawn line-gestures, zooming navigation, and simple symbolic icons, that helps make this program unique. The program was designed to enable musically untrained children, ages ten or older, to compose three-minute pieces for a string orchestra, given only a week or so of two-hour daily workshops. The program succeeded in this, and has been presented to audiences in Berlin, Dublin, and Glasgow as a part of Toy Symphony. The program has also been made available for download.
by Egon Pasztor.
S.M.
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Clegg, Nicola Aylsa. "Modelling sea-salt aerosol composition in the marine environment." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286292.

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Anderson, Tim M. "E-SCAPE : an extendible sonic composition and performance environment." Thesis, University of York, 1993. http://etheses.whiterose.ac.uk/21040/.

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Oliva, Martin Lisandro. "Genotype, environment and GE interaction effect on soybean oil composition." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4253.

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Thesis (M.S.)--University of Missouri-Columbia, 2005.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (December 18, 2006). Includes bibliographical references.
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Books on the topic "Equilibrium composition of the environment"

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Barocio-Delgado, Samuel R. A tokamak equilibrium environment through topological dynamics. Manchester: UMIST, 1997.

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Saint-Paul, Gilles. Equilibrium allele distribution in trading populations. Bonn, Germany: IZA, 2006.

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Beghin, John, David Roland-Holst, and Dominique Mensbrugghe, eds. Trade and the Environment in General Equilibrium: Evidence from Developing Economies. Dordrecht: Kluwer Academic Publishers, 2002. http://dx.doi.org/10.1007/0-306-47672-x.

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name, No. Trade and the environment in general equilibrium: Evidence from developing economies. Dordrecht: Kluwer Academic, 2001.

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Shikazono, Naotatsu. Electrum: Chemical composition, mode of occurrence, and depositional environment. Tokyo: University Museum, University of Tokyo, 1988.

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Hoffman, Eric. An introduction to teaching composition in an electronic environment. Boston: Allyn & Bacon, 2000.

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Mahinda, Siriwardana, ed. A computable general equilibrium model for environment policy analysis: The case of deforestation in the Philippines. Hauppauge, N.Y: Nova Science Publishers, 2009.

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Jacob, Greg P. Writing and eco-consciousness: Matters of composition and the environment. Redding, CA: CAT Pub. Co., 2002.

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Hinton, Heather Maria. An environment-based approach to the composition of safe systems. Ottawa: National Library of Canada, 1993.

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Val, Adalberto Luís. Fishes of the Amazon and their environment: Physiological and biochemical aspect. Berlin: Springer, 1995.

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Book chapters on the topic "Equilibrium composition of the environment"

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Hanby, Victor Ian. "Equilibrium Composition of Flames." In Combustion and Pollution Control in Heating Systems, 48–60. London: Springer London, 1994. http://dx.doi.org/10.1007/978-1-4471-2071-1_5.

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Lee, Albert J. "Environment and Equilibrium." In Taxation, Growth and Fiscal Institutions, 5–19. New York, NY: Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4614-1290-8_2.

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Souchez, Roland A., and Reginald D. Lorrain. "Ice Composition." In Springer Series in Physical Environment, 29–75. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-58187-8_2.

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Eisma, Doeke. "Particle Composition." In Suspended Matter in the Aquatic Environment, 52–77. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-77722-6_4.

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McCoy, Bill N., and John L. Dewey. "Equilibrium Composition of Sodium Aluminate Liquors." In Essential Readings in Light Metals, 148–54. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118647868.ch19.

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McCoy, Bill N., and John L. Dewey. "Equilibrium Composition of Sodium Aluminate Liquors." In Essential Readings in Light Metals, 148–54. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-48176-0_19.

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Swaine, D. J. "The Formation, Composition and Utilisation of Flyash." In Energy & Environment, 204–20. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-015-8496-8_11.

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Bose, Tarit K. "Equilibrium Composition of a Reacting Gas Mixture." In High Temperature Gas Dynamics, 135–66. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-662-07762-7_6.

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Bose, Tarit K. "Equilibrium Composition of a Reacting Gas Mixture." In High Temperature Gas Dynamics, 225–58. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-05200-7_6.

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Alpay, Savaş. "Partial Equilibrium Models of Trade and Environment." In Trade and The Environment, 17–29. Boston, MA: Springer US, 2002. http://dx.doi.org/10.1007/978-1-4615-0271-5_3.

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Conference papers on the topic "Equilibrium composition of the environment"

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Pan, Li, Bo An, Shijun Liu, and Lizhen Cui. "Nash Equilibrium and Decentralized Pricing for QoS Aware Service Composition in Cloud Computing Environments." In 2017 IEEE International Conference on Web Services (ICWS). IEEE, 2017. http://dx.doi.org/10.1109/icws.2017.28.

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Damiani, Lorenzo, and Angela Trucco. "Biomass Gasification Modelling: An Equilibrium Model, Modified to Reproduce the Operation of Actual Reactors." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-60323.

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This paper presents a modified equilibrium simulation model for biomass gasification performance prediction. The model, implemented in the Matlab-Simulink® environment, is able to calculate the reactor main operating parameters, such as reaction temperature, gas composition, gas flow rate and solid product (typically charcoal). The comparison of model output with experimental data puts in evidence the insufficient precision of equilibrium models, due to their incapability of taking into account the non equilibrium effects always present in the gasification process. To obtain a better prediction of measured values the pure equilibrium model has been modified on the basis of literature experimental data, introducing semi-empirical correlations with the aim to consider the most meaningful effects of non-equilibrium. The results demonstrate that this modification leads to an increased precision of the model in reproducing experimental data.
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Abdul-Sater, Hassan, James Lenertz, Chris Bonilha, Xijia Lu, and Jeremy Fetvedt. "A CFD Simulation of Coal Syngas Oxy-Combustion in a High-Pressure Supercritical CO2 Environment." In ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gt2017-63821.

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The Allam Cycle is an oxy-fuel supercritical CO2 power cycle that generates low-cost electricity from fossil fuels while producing near-zero air emissions. The turbine exhaust (sCO2) is then available for partial injection into underground storage while remainder is reused in the power cycle. Novel combustors required by this and other sCO2 cycles are critical to their commercialization. A conceptual design was developed for a coal syngas-fueled oxy-fuel combustor that meets the conditions of the Allam Cycle. The design of this combustor utilizes a 300MWe coal syngas-fired Allam Cycle thermodynamic analyses and ASPEN process models as inputs to the combustor. The primary inputs for design of the combustor included the fuel mixture compositions and respective flow rates for the constituent gases, pressures, and operating temperatures which were scaled to a 5MWth test article. The combustor was sized to accommodate the required pressures, heat release rate, flow rates, and residence times to produce well mixed turbine inlet flows with complete combustion. A preliminary design for a 5MWth test scale combustor was then developed, and a numerical study using Computational Fluid Dynamics (CFD) simulations was carried out to demonstrate the feasibility of that combustor. Steady-state RANS simulations were used to qualitatively examine the preliminary design of the 5MWth combustor and predict the fluid mechanics, heat transfer, and combustion. The purpose of the analysis was to verify the following criteria: 1) good mixing of the fuel and oxidizer in the primary zone, 2) uniform exhaust gas temperature and 3) efficient combustion with complete CO burnout. Additionally, the analysis investigated wall temperature and the impact of varying the fuel composition on combustion performance. The CFD model results were in good agreement with the equilibrium one-dimensional (1D) Aspen model results. The CFD predictions of the current conceptual design verified the identified key criteria for the combustor and demonstrated its feasibility.
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Mika, Martin, Milan Patek, Jaroslav Maixner, Simona Randakova, and Pavel Hrma. "The Effect of Temperature and Composition on Spinel Concentration and Crystal Size in High-Level Waste Glass." In ASME 2001 8th International Conference on Radioactive Waste Management and Environmental Remediation. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/icem2001-1324.

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Abstract High-level radioactive wastes can be safely immobilized in alkali-aluminoborosilicate glass. To reduce the cost of the vitrification process, the waste loading should be maximized. This can be done by optimizing the process using mathematical modeling. The main objective of our work was to determine one of the necessary inputs for the mathematical model, which is the effect of temperature and composition on the concentration of spinel crystals and their size. We prepared six glasses with a different content of Li+, Na+, Mg2+, Ni2+, Cr3+, and SiIV and studied the effect of composition on the temperature dependence of spinel equilibrium concentration in glass by X-ray powder diffraction. The size of crystals was determined using optical microscopy. It was found that the temperature effect on spinel concentration significantly increased as the content of Ni2+ or Mg2+ in glass increased and slightly decreased as the content of Cr3+ increased and Li+ and Na+ content decreased. Both Ni2+ and Cr3+ acted as nucleating agents, producing a huge number of tiny spinel crystals (∼2 μm). In particular, Ni2+ seems to very significantly facilitate spinel crystallization.
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Stengele, J., H. J. Bauer, and S. Wittig. "Numerical Study of Bicomponent Droplet Vaporization in a High Pressure Environment." 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-442.

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The understanding of multicomponent droplet evaporation in a high pressure and high temperature gas is of great importance for the design of modern gas turbine combustors, since the different volatilities of the droplet components affect strongly the vapor concentration and, therefore, the ignition and combustion process in the gas phase. Plenty of experimental and numerical research is already done to understand the droplet evaporation process. Until now, most numerical studies were carried out for single component droplets, but there is still lack of knowledge concerning evaporation of multicomponent droplets under supercritical pressures. In the study presented, the Diffusion Limit Model is applied to predict bicomponent droplet vaporization. The calculations are carried out for a stagnant droplet consisting of heptane and dodecane evaporating in a stagnant high pressure and high temperature nitrogen environment. Different temperature and pressure levels are analyzed in order to characterize their influence on the vaporization behavior. The model employed is fully transient in the liquid and the gas phase. It accounts for real gas effects, ambient gas solubility in the liquid phase, high pressure phase equilibrium and variable properties in the droplet and surrounding gas. It is found that for high gas temperatures (T = 2000 K) the evaporation time of the bicomponent droplet decreases with higher pressures, whereas for moderate gas temperatures (T = 800 K) the lifetime of the droplet first increases and then decreases when elevating the pressure. This is comparable to numerical results conducted with single component droplets. Generally, the droplet temperature increases with higher pressures reaching finally the critical mixture temperature of the fuel components. The numerical study shows also that the same tendencies of vapor concentration at the droplet surface and vapor mass flow are observed for different pressures. Additionally, there is almost no influence of the ambient pressure on fuel composition inside the droplet during the evaporation process.
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Contreras, Mari´a F., and Gerardo Gordillo. "Comparison of Models Used to Predict the Gas Composition of Mixtures Produces by Gasification of Wax Palm Husk Using Air-Steam for Partial Oxidation." In ASME/JSME 2011 8th Thermal Engineering Joint Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajtec2011-44308.

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There are eleven species of wax palm in South America which produce a great amount of biomass per year (∼590 ton/ha). This biomass has not any commercial value and can cause a negative impact on the environment if waste handling systems and storage and treatment structures are not accurately controlled. However, this biomass can serve as feedstock for thermal gasification (partial oxidation and pyrolysis) to produce gaseous and liquid fuels. The current paper presents results on modeling studies to predict the gas composition of mixtures produced by gasification of wax palm husk (WPH) using air–steam for partial oxidation. The parameters investigated by equilibrium model are equivalence ratio and steam-fuel ratio. With the predicted composition of gases, the high heating value was estimated. Atom model was used for comparison purposes. Also, a kinetics model of the pyrolysis of WPH is presented. Thermogravimetric analysis was used to estimate the activation energy and the pre-exponential factor of Arrhenius equation. The results suggest that it is possible to produce gaseous fuels with concentrations of H2 ranging from 5 to 30%, CO from 10 to 19%, and CH4 from 0 to 4%. The activation energy estimated with kinetics model was estimated to be 143.07 kJ mol−1.
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7

Privat, Romain, Freddy Garcia, Jean-Noe¨l Jaubert, and Michel Molie`re. "Ethanol-Hydrocarbon Blend Vapor Prediction." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59336.

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In the volatile fuel price environment of today, the quest for alternative fuels has become a heavy and long term trend in power generation worldwide. Incorporating alternative fuels in gas turbine installations raises multiple engineering questions relating to combustion, emissions, on-base and auxiliary hardware capability, safety etc. In 2008, GE carried out a field test aimed at characterizing the combustion of ethanol in a naphtha fuelled gas turbine plant. The testing strategy has been to locally prepare and burn ethanol-naphtha blends with a fraction of ethanol increasing from 0 to nearly 100%. During the engineering phase prior to this field test, it appeared necessary to develop a sufficient knowledge on the behavior of ethanol-hydrocarbon blends in order to establish the safety analysis and address in particular the risks of (i) a potential uncontrolled ignition event in the air blanket of fuel tanks and (ii) flash vaporization of a potential fuel pond in a confined environment. Although some results exist in the car engine literature for ethanol-gasoline blends, it was necessary to take into account the specificities of gas turbine applications, namely (i) the much greater potential ethanol concentration range (from 0 to 100%) and (ii) the vast composition spectrum of naphtha likely to generate a much larger Reid Vapor Pressure envelope as compared with automotive applications. In order to fulfill the safety needs of this field test, the “Laboratoire de Thermodynamique des Milieux Polyphase´s” (LTMP) of Nancy, France has developed a thermodynamic model to approach the vaporization equilibria of ethanol-hydrocarbons mixtures with variable ethanol strength and naphtha composition. This model, named PPR78, is based on the 1978 Peng-Robinson equation of state and allows the estimation of the thermodynamic properties of a multicomponent mixture made of ethanol and naphtha compounds by using the group contribution concept. The saturation equilibrium partial pressure of such fluids in the various situations of relevance for the safety analysis can thus be calculated. The paper reports the elaboration of this model and illustrates the results obtained when using it in different safety configurations.
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Shibuya, M., Y. Suzuki, H. Shimizu, M. Inoue, H. Kaneki, N. Moriya, E. Ochi, and H. Aoyagi. "Study on Reduction of Liquid Waste From Reprocessing Plant by Electrolysis Process." In ASME 2001 8th International Conference on Radioactive Waste Management and Environmental Remediation. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/icem2001-1298.

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Abstract The reduction of radioactive waste volume is an important issue for the management of the nuclear fuel cycle. The purpose of this study is to create a technique to drastically reduce low-level liquid waste generated by a spent fuel reprocessing plant employing PUREX technology. In the PUREX plant, NOx gas is used as an oxidizing reagent for adjustment of the Pu valence in the Pu purification stage. The spent NOx gas is recovered as nitric acid and a certain amount of recovered nitric acid becomes low-level waste (LLW). As NOx gas is produced by the chemical reaction of nitric acid and sodium nitrite, a considerable quantity of non-radioactive sodium nitrate solution is discharged. From the standpoint of the impact on the environment, this discharge must be reduced. The objective of this research is to develop an electrolysis process by which NOx gas is directly produced from recovered nitric acid. Using this technology, the low-level sodium nitrate waste can be reduced and the nonradioactive sodium nitrate waste from the present NOx production process can be entirely eliminated. The study was performed in the following two steps: Phase 1: Fundamental research; Phase 2: Engineering study. Fundamental research: A study on the conditions of nitric acid decomposition by electrolysis was performed. The composition of NO and NO2 and its quantity are determined by electrolyte concentration, cathode material and current density. Catholyte reduced electrochemically is in a state of chemical equilibrium expressed by NO, NO2 (N2O4), HNO2, HNO3 and H2O. Nitric acid concentration, temperature and partial pressure of NOx are important process parameters since NOx generation current efficiency and NOx gas composition are dependent on a chemical equilibrium. Engineering study: The pilot plant was designed and constructed. The process configuration of the pilot plant is the same as that of the anticipated actual plant and its NOx generation capacity is one eighth of the actual plant. The plant mainly consists of electrolysis unit, NOx compression and storage unit, sodium nitrite oxidation unit, nitric acid distillation unit, and NOx recovery and off-gas treatment unit. NOx gas and HNO2 are generated as a result of nitric acid reduction in the electrolysis unit. NOx gas is transported under negative pressure to the compression/storage unit by a compressor and is stored in tanks under high pressure. After adjustment of gas composition by O2 supply, NOx gas is fed to the user process in the case of an actual plant. In the pilot test plant, NOx gas is transported to the nitric acid recovery step, in which NOx gas is recovered as nitric acid and reused in the pilot plant. As a result of operation of the pilot plant, the process performance, equipment performance, and long-term operation stability were proven. It was confirmed through the pilot plant operation that this technology was immediately applicable to a PUREX reprocessing plant.
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Horlock, J. H., J. B. Young, and G. Manfrida. "The Rational Efficiency of Fossil-Fuel Power Plants." In ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-0848.

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Abstract The definition of open cycle rational efficiency is unequivocally based on the ratio of the actual shaft work output from a power plant to the maximum work that could be obtained in a reversible process between prescribed inlet and outlet states. However, the specification of this ideal process remains a matter for discussion. The “classical” definition specifies the outlet state as a “standard” atmosphere (p0,T0) with a given composition of constituent gases and an exergy of zero. The ideal work output is then the exergy of the fuel supplied, which is the sum of the Gibbs function change in reversible combustion at (p0,T0) and the work of extraction and delivery of the reactant and product species. However, two other ideal processes may be considered in which different outlet states are specified leading to alternative definitions of rational efficiency. In one process all species enter and leave the ideal plant individually at (p0,T0) in thermal and mechanical (but not chemical) equilibrium with the environment. In the other, the exhaust is at (p0,T0) but the gas composition is the same as in the real process. A further complication occurs when water or steam is injected into a gas turbine plant. In such cases the exergy of the added water must be considered within any definition of rational efficiency. The three definitions of rational efficiency are discussed and compared and some illustrative calculations presented.
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Sirignano, William A., and Albert Jorda Juanos. "Analytical / Computational Approach to Liquid Spray Heating and Vaporization at Supercritical Pressures." In ILASS2017 - 28th European Conference on Liquid Atomization and Spray Systems. Valencia: Universitat Politècnica València, 2017. http://dx.doi.org/10.4995/ilass2017.2017.4615.

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Our findings from two areas of background research will define an approach to the study of liquid spray heating andvaporization in gases at supercritical pressure: (i) vaporizing droplets at supercritical pressure and (ii) supercritical combustion in simple configurations, e.g., counterflow. The a priori conclusion that only one phase exists at super- critical pressure is based on false “lore” and not physical law. The question about the phases must be left open until the analysis reaches a conclusion; a proper approach will be defined. Proper equations of state for density and en- thalpy and the determination of phase equilibrium, liquid composition due to dissolved gas, energy of vaporization, surface tension, and transport properties for high pressures will be discussed. The case of an isolated droplet will be reviewed and origin of the transcritical concept will be explained. A counterflow spray configuration at pressures above the liquid critical pressure will be analyzed. The concept of shifting phase equilibrium will be applied as the droplets in the spray heat. Hydrocarbon liquids and oxidizing gaseous environments will be studied. Differences between real fluids and ideal fluids at high pressures will be emphasized. Proper rules for gaseous mixtures andliquid solutions will be discussed.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4615
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Reports on the topic "Equilibrium composition of the environment"

1

Wynblatt, P. Equilibrium composition of interphase boundaries. Office of Scientific and Technical Information (OSTI), January 1990. http://dx.doi.org/10.2172/6390291.

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Wynblatt, P. [Equilibrium composition of interphase boundaries]. Final report. Office of Scientific and Technical Information (OSTI), October 1998. http://dx.doi.org/10.2172/362510.

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Carlson, Patricia, and Melinda L. Crevoisier. R-WISE: A Learning Environment to Teach Prose Composition. Fort Belvoir, VA: Defense Technical Information Center, June 1995. http://dx.doi.org/10.21236/ada303684.

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Elmore, Ryan, Kenny Gruchalla, Caleb Phillips, Avi Purkayastha, and Nick Wunder. Analysis of Application Power and Schedule Composition in a High Performance Computing Environment. Office of Scientific and Technical Information (OSTI), January 2016. http://dx.doi.org/10.2172/1235236.

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Farber, Henry. Union Organizing Decisions in a Deteriorating Environment: The Composition of Representation Elections and the Decline in Turnout. Cambridge, MA: National Bureau of Economic Research, February 2014. http://dx.doi.org/10.3386/w19908.

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Whitbeck, M., and W. Glassley. Preliminary bounds on the water composition and secondary mineral development that may influence the near-field environment. Office of Scientific and Technical Information (OSTI), February 1998. http://dx.doi.org/10.2172/641265.

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McMartin, I., P. J. Henderson, E. Nielsen, and J. E. Campbell. Surficial geology, till and humus composition across the Shield margin, north-central Manitoba and Saskatchewan: geospatial analysis of a glaciated environment. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1996. http://dx.doi.org/10.4095/207748.

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Бєлик, Юлія Вільєвна, Василь Миколайович Савосько, and Юрій Вікторович Лихолат. Taxonomic Composition and Synanthropic Characteristic of Woody Plant Community on Petrovsky Waste Rock Dumps (Kryvorizhzhya). КДПУ, 2019. http://dx.doi.org/10.31812/123456789/3640.

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The study of taxonomic composition and ecological characteristics of wood species on devastated lands as a theoretical basis for the phytomelioration of environment remains relevant nowadays. It was discovered 32 species, 25 genera and 15 families in the course of the analysis of woody plant community from devastated lands of Petrovsky waste rock dumps. Among them, allochthonous species (59.38%) have an advantage over autochthonous (40.63%) according to the quantitative indicators. It was established, hemiapophytes predominate among apophytesspecies andneophytes predominate among anthropophytesaccording to the time of entry, according to the method of invasion ergasiophytes, according to the degree of adaptation ergasiophytes and agriophytes. The results of our analysis indicate that the investigated woody plant communitycorresponds to the conditions of localization.
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Shenker, Moshe, Paul R. Bloom, Abraham Shaviv, Adina Paytan, Barbara J. Cade-Menun, Yona Chen, and Jorge Tarchitzky. Fate of Phosphorus Originated from Treated Wastewater and Biosolids in Soils: Speciation, Transport, and Accumulation. United States Department of Agriculture, June 2011. http://dx.doi.org/10.32747/2011.7697103.bard.

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Beneficial use of reclaimed wastewater (RW) and biosolids (BS) in soils is accompanied by large input of sewage-originated P. Prolonged application may result in P accumulation up to levelsBeneficial use of reclaimed wastewater (RW) and biosolids (BS) in soils is accompanied by large input of sewage-originated P. Prolonged application may result in P accumulation up to levels that impair plant nutrition, increase P loss, and promote eutrophication in downstream waters. This study aims to shed light on the RW- and BS-P forms in soils and to follow the processes that determine P reactivity, solubility, availability, and loss in RW and BS treated soils. The Technion group used sequential P extraction combined with measuring stable oxygen isotopic composition in phosphate (δ18OP) and with 31P-NMR studies to probe P speciation and transformations in soils irrigated with RW or fresh water (FW). The application of the δ18OP method to probe inorganic P (Pi) speciation and transformations in soils was developed through collaboration between the Technion and the UCSC groups. The method was used to trace Pi in water-, NaHCO3-, NaOH-, and HCl- P fractions in a calcareous clay soil (Acre, Israel) irrigated with RW or FW. The δ18OP signature changes during a month of incubation indicated biogeochemical processes. The water soluble Pi (WSPi) was affected by enzymatic activity yielding isotopic equilibrium with the water molecules in the soil solution. Further it interacted rapidly with the NaHCO3-Pi. The more stable Pi pools also exhibited isotopic alterations in the first two weeks after P application, likely related to microbial activity. Isotopic depletion which could result from organic P (PO) mineralization was followed by enrichment which may result from biologic discrimination in the uptake. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with RW. Specific P compounds were identified by the Technion group, using solution-state 31P-NMR in wastewater and in soil P extracts from Acre soils irrigated by RW and FW. Few identified PO compounds (e.g., D-glucose-6-phosphate) indicated coupled transformations of P and C in the wastewater. The RW soil retained higher P content, mainly in the labile fractions, but lower labile PO, than the FW soil; this and the fact that P species in the various soil extracts of the RW soil appear independent of P species in the RW are attributed to enhanced biological activity and P recycling in the RW soil. Consistent with that, both soils retained very similar P species in the soil pools. The HUJ group tested P stabilization to maximize the environmental safe application rates and the agronomic beneficial use of BS. Sequential P extraction indicated that the most reactive BS-P forms: WSP, membrane-P, and NaHCO3-P, were effectively stabilized by ferrous sulfate (FeSul), calcium oxide (CaO), or aluminum sulfate (alum). After applying the stabilized BS, or fresh BS (FBS), FBS compost (BSC), or P fertilizer (KH2PO4) to an alluvial soil, P availability was probed during 100 days of incubation. A plant-based bioassay indicated that P availability followed the order KH2PO4 >> alum-BS > BSC ≥ FBS > CaO-BS >> FeSul-BS. The WSPi concentration in soil increased following FBS or BSC application, and P mineralization further increased it during incubation. In contrast, the chemically stabilized BS reduced WSPi concentrations relative to the untreated soil. It was concluded that the chemically stabilized BS effectively controlled WSPi in the soil while still supplying P to support plant growth. Using the sequential extraction procedure the persistence of P availability in BS treated soils was shown to be of a long-term nature. 15 years after the last BS application to MN soils that were annually amended for 20 years by heavy rates of BS, about 25% of the added BS-P was found in the labile fractions. The UMN group further probed soil-P speciation in these soils by bulk and micro X-ray absorption near edge structure (XANES). This newly developed method was shown to be a powerful tool for P speciation in soils. In a control soil (no BS added), 54% of the total P was PO and it was mostly identified as phytic acid; 15% was identified as brushite and 26% as strengite. A corn crop BS amended soil included mostly P-Fe-peat complex, variscite and Al-P-peat complex but no Ca-P while in a BS-grass soil octacalcium phosphate was identified and o-phosphorylethanolamine or phytic acid was shown to dominate the PO fraction that impair plant nutrition, increase P loss, and promote eutrophication in downstream waters. This study aims to shed light on the RW- and BS-P forms in soils and to follow the processes that determine P reactivity, solubility, availability, and loss in RW and BS treated soils. The Technion group used sequential P extraction combined with measuring stable oxygen isotopic composition in phosphate (δ18OP) and with 31P-NMR studies to probe P speciation and transformations in soils irrigated with RW or fresh water (FW). The application of the δ18OP method to probe inorganic P (Pi) speciation and transformations in soils was developed through collaboration between the Technion and the UCSC groups. The method was used to trace Pi in water-, NaHCO3-, NaOH-, and HCl- P fractions in a calcareous clay soil (Acre, Israel) irrigated with RW or FW. The δ18OP signature changes during a month of incubation indicated biogeochemical processes. The water soluble Pi (WSPi) was affected by enzymatic activity yielding isotopic equilibrium with the water molecules in the soil solution. Further it interacted rapidly with the NaHCO3-Pi. The more stable Pi pools also exhibited isotopic alterations in the first two weeks after P application, likely related to microbial activity. Isotopic depletion which could result from organic P (PO) mineralization was followed by enrichment which may result from biologic discrimination in the uptake. Similar transformations were observed in both soils although transformations related to biological activity were more pronounced in the soil treated with RW. Specific P compounds were identified by the Technion group, using solution-state 31P-NMR in wastewater and in soil P extracts from Acre soils irrigated by RW and FW. Few identified PO compounds (e.g., D-glucose-6-phosphate) indicated coupled transformations of P and C in the wastewater. The RW soil retained higher P content, mainly in the labile fractions, but lower labile PO, than the FW soil; this and the fact that P species in the various soil extracts of the RW soil appear independent of P species in the RW are attributed to enhanced biological activity and P recycling in the RW soil. Consistent with that, both soils retained very similar P species in the soil pools. The HUJ group tested P stabilization to maximize the environmental safe application rates and the agronomic beneficial use of BS. Sequential P extraction indicated that the most reactive BS-P forms: WSP, membrane-P, and NaHCO3-P, were effectively stabilized by ferrous sulfate (FeSul), calcium oxide (CaO), or aluminum sulfate (alum). After applying the stabilized BS, or fresh BS (FBS), FBS compost (BSC), or P fertilizer (KH2PO4) to an alluvial soil, P availability was probed during 100 days of incubation. A plant-based bioassay indicated that P availability followed the order KH2PO4 >> alum-BS > BSC ≥ FBS > CaO-BS >> FeSul-BS. The WSPi concentration in soil increased following FBS or BSC application, and P mineralization further increased it during incubation. In contrast, the chemically stabilized BS reduced WSPi concentrations relative to the untreated soil. It was concluded that the chemically stabilized BS effectively controlled WSPi in the soil while still supplying P to support plant growth. Using the sequential extraction procedure the persistence of P availability in BS treated soils was shown to be of a long-term nature. 15 years after the last BS application to MN soils that were annually amended for 20 years by heavy rates of BS, about 25% of the added BS-P was found in the labile fractions. The UMN group further probed soil-P speciation in these soils by bulk and micro X-ray absorption near edge structure (XANES). This newly developed method was shown to be a powerful tool for P speciation in soils. In a control soil (no BS added), 54% of the total P was PO and it was mostly identified as phytic acid; 15% was identified as brushite and 26% as strengite. A corn crop BS amended soil included mostly P-Fe-peat complex, variscite and Al-P-peat complex but no Ca-P while in a BS-grass soil octacalcium phosphate was identified and o-phosphorylethanolamine or phytic acid was shown to dominate the PO fraction.
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Wilkins, Justin, Andrew McQueen, Joshua LeMonte, and Burton Suedel. Initial survey of microplastics in bottom sediments from United States waterways. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/42021.

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Given the reported extent of microplastics in the aquatic environment, environmentally relevant exposure information for sediments dredged by the US Army Corps of Engineers will lend context to the risks posed by this contaminant during dredging. We measured the occurrence, abundance, and polymer composition of microplastics in sediments collected from nine dredged waterways and two non-dredged reference areas. The number of particles in sediment samples ranged from 162 to 6110 particles/kg dry wt., with a mean of 1636 particles/kg dry wt. Fragments were the most prevalent shape observed among the 11 study sites (100% frequency of occurrence), followed by fibers (81%), spheres (75%), foams (38%) and films (34%). Based on analyses of chemical composition of the particles using Fourier transform infrared spectroscopy, polyethylene:propylene was the most common polymer type observed. Consistent with results presented by other investigators microplastic concentrations and polymer types in bottom sediments in this study were also aligned with the most widely used plastics worldwide.
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