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Academic literature on the topic 'Flow chemistry approach'

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Published: 10 December 2022
Last updated: 30 January 2023

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Journal articles on the topic "Flow chemistry approach"

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Guidi, Mara, Peter H. Seeberger, and Kerry Gilmore. "How to approach flow chemistry." Chemical Society Reviews 49, no. 24 (2020): 8910–32. http://dx.doi.org/10.1039/c9cs00832b.

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The intrinsic attributes of flow chemistry that facilitate and provide reproducible access to a range of processes are best exploited using modules targeting an overall effect: a selective transformation or the generation of a reactive intermediate.
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Lévesque, François, Nicholas J. Rogus, Glenn Spencer, Plamen Grigorov, Jonathan P. McMullen, David A. Thaisrivongs, Ian W. Davies, and John R. Naber. "Advancing Flow Chemistry Portability: A Simplified Approach to Scaling Up Flow Chemistry." Organic Process Research & Development 22, no. 8 (June 27, 2018): 1015–21. http://dx.doi.org/10.1021/acs.oprd.8b00063.

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Tarleton, Mark, Kelly A. Young, Elli Unicomb, Siobhann N. McCluskey, Mark J. Robertson, Christopher P. Gordon, and Adam McCluskey. "A Flow Chemistry Approach to Norcantharidin Analogues." Letters in Drug Design & Discovery 8, no. 6 (July 1, 2011): 568–74. http://dx.doi.org/10.2174/157018011795906730.

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Wheeler, Rob C., Otman Benali, Martyn Deal, Elizabeth Farrant, Simon J. F. MacDonald, and Brian H. Warrington. "Mesoscale Flow Chemistry: A Plug-Flow Approach to Reaction Optimisation." Organic Process Research & Development 11, no. 4 (July 2007): 704–10. http://dx.doi.org/10.1021/op7000707.

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Wilson, Noel S., Augustine T. Osuma, Jennifer A. Van Camp, and Xiangdong Xu. "A scalable approach to diaminopyrazoles using flow chemistry." Tetrahedron Letters 53, no. 34 (August 2012): 4498–501. http://dx.doi.org/10.1016/j.tetlet.2012.05.152.

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Luque Navarro, Pilar María, and Daniela Lanari. "Flow Synthesis of Biologically-Relevant Compound Libraries." Molecules 25, no. 4 (February 18, 2020): 909. http://dx.doi.org/10.3390/molecules25040909.

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Flow chemistry is one of the most prominent enabling technologies that has greatly shaped the way chemists’ approach organic synthesis. Specifically, in drug discovery, the advantages of flow techniques over batch procedures allow the rapid and efficient assembly of compound libraries to be tested for biological properties. The aim of the present review is to comment on some representative examples from the last five years of literature that highlight how flow procedures are becoming of increasing importance for the synthesis of biologically-relevant molecules.
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Wilson, Noel S., Augustine T. Osuma, Jennifer A. Van Camp, and Xiangdong Xu. "ChemInform Abstract: A Scalable Approach to Diaminopyrazoles Using Flow Chemistry." ChemInform 43, no. 48 (November 8, 2012): no. http://dx.doi.org/10.1002/chin.201248117.

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Wang, Xue D., Terence J. Cardwell, Robert W. Cattrall, and Graeme E. Jenkins. "Pulsed flow chemistry. A new approach to the generation of concentration profiles in flow analysis." Analytical Communications 35, no. 3 (1998): 97–101. http://dx.doi.org/10.1039/a708659h.

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Mándity, István M., Tamás A. Martinek, Ferenc Darvas, and Ferenc Fülöp. "A simple, efficient, and selective deuteration via a flow chemistry approach." Tetrahedron Letters 50, no. 30 (July 2009): 4372–74. http://dx.doi.org/10.1016/j.tetlet.2009.05.050.

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Socol, Marius, and Ioan Baldea. "A New Approach of Flow Graph Theory Applied in Physical Chemistry." Journal of the Chinese Chemical Society 53, no. 4 (August 2006): 773–81. http://dx.doi.org/10.1002/jccs.200600103.

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Dissertations / Theses on the topic "Flow chemistry approach"

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Matson, Cole Wesley. "Combining environmental chemistry, somatic biomarkers, and population genetics: an innovative approach in wildlife ecotoxicology." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/72.

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The Caspian region and specifically the Apsheron peninsula of Azerbaijan is known to be polluted with a variety of environmental contaminants, making risk assessment difficult. The wetlands of Sumgayit contain particularly complex mixtures of contaminants. Flow cytometry and the micronucleus assay were used to assess chromosomal damage in aquatic turtles and frogs inhabiting contaminated wetlands in Azerbaijan. By evaluating biomarkers that are indicative of somatic effects, elevated chromosomal damage was documented at several sites in Azerbaijan relative to reference sites. Sediment samples were analyzed for polycyclic aromatic hydrocarbons (PAHs), organochlorines (OCs), and mercury to evaluate contaminant associations with genetic damage. Sediment samples revealed heterogeneous patterns of PAH and mercury concentrations throughout Sumgayit. Significant positive correlations were documented between both PAH and mercury sediment concentrations and chromosomal damage. Population genetic methods were employed to study the effects of long-term chronic contaminant exposure in marsh frogs from Sumgayit. The Sumgayit region has reduced levels of genetic diversity, likely due to environmental degradation. One of the most contaminated sites in Sumgayit, WTP, appears to be a source of new mutations as a result of an increased mutation rate. Finally, the Sumgayit region seems to act as an ecological sink, with levels of gene flow into the region exceeding gene flow out of the region. This study provides not only exposure and biomarker data, but also an integrated method for assessing the cumulative population impacts of contaminant exposure by studying both population genetic and evolutionary effects. The results presented here will be used in conjunction with those of ongoing research involving both wildlife and humans to develop comprehensive ecological and human risk assessments.
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Martin, Alex D. "A Convergent Approach to the Continuous Synthesis of Telmisartan via a Suzuki Reaction between Two Functionalized Benzimidazoles." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3750.

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A direct and highly efficient synthesis has been developed for telmisartan, the active ingredient in the widely prescribed antihypertensive drug Micardis®. This approach brings together two functionalized benzimidazoles using a high-yielding Suzuki reaction that can be catalyzed by a homogeneous palladium source or palladium on a solid support. The ability to perform the cross-coupling reaction was facilitated by the regio-controlled preparation of a 2-bromo-1-methylbenzimidazole precursor. The method developed is the first reported selective bromination at the 2-position of a benzimidazole and produces the first major precursor in high yield (93%). The second precursor, potassium (4-methyl-2-propylbenzimidazol-6-yl) trifluoroborate, was prepared from commercially available 4-bromo-2-methyl-6-nitroaniline. An optimized preparation is described that provides a direct three-step process to prepare the benzimidazole and install the borate; this synthetic sequence yields the second precursor with a 90% yield and no isolated intermediates. The two prepared precursors were combined with a third, commercially available methyl-4’-(bromomethyl)-[1,1’-biphenyl]-2-carboxylate, utilizing a short sequence of high yielding reactions to produce the telmisartan with an 83% yield from these advanced intermediates. This new convergent approach provides the active drug ingredient with an overall yield of 74% while circumventing many issues associated with the previously reported processes. Additionally, a flow-based synthesis of telmisartan was achieved with no intermediate purifications or solvent exchanges. The continuous process utilizes a tubular reactor system coupled with a plug flow cartridge, ultimately delivering telmisartan in an 86% isolated yield.
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Dorney, Kevin Michael. "A Chemical Free Approach for Increasing the Biochemical Surface-Enhanced Raman Spectroscopy (SERS)-Based Sensing Capabilities of Colloidal Silver Nanoparticles." Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1401206511.

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Scatena, Gabriel dos Santos. "Multicomponent approach to silica-grafted peptide catalysts : A 3 D continuous-flow organocatalytic system with on-line monitoring of conversion and stereo-selectivity." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/8017.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
The derivatization of organocatalysts with functional appendages suitable to anchor onto solid supports is usually achieved by stepwise syntheses. As an alternative to such a strategy, this work describes a one-pot approach to silylated prolyl-peptide catalysts by a multicomponent reaction that enables the simultaneous incorporation of the catalytic and the heterogenizable (triethoxysilane) moieties. A microreactor with high catalytic efficacy and reproducibly in the conjugate addition of aldehydes to nitroolefins was obtained by grafting onto HPLC-grade silica (10 μm) and packing into a column with a selected catalyst. A 3 D continuous-flow system that includes the on-line monitoring of the reaction outcome was set up. For that, the microreactor was coupled to a chromatographic column for the separation of the remaining substrates from the Michael adduct in the second dimension, followed by a chiral polysaccharide column for the analysis of conversion and stereoselectivity. This approach represents a new instrumental setup that combines the advantages of multidimensional chromatography and flow catalysis.
A derivação de Organocatalisadores com apêndices funcionais adequados para ancorar em suportes sólidos é geralmente obtida por síntese “passo a passo”. Como uma alternativa para tal estratégia, este trabalho descreve uma abordagem de síntese one-pot de catalisadores prolil-peptio sililados através de uma reação multicomponentes, que permite a incorporação simultânea do sítio catalítico e o grupo funcional de ancoragem (trietoxisilano). Um micro-reactor foi obtido, tendo elevada eficácia catalítica e reprodutibilidade, na adição conjugada de aldeídos a nitro-olefinas, enxertando sobre sílica de grau HPLC (10 um) e preenchendo uma coluna com um catalisador escolhido. Um sistema de fluxo contínuo 3D que inclui a monitoração em linha do resultado da reação foi ajustado para cima. Para isso, o micro-reator foi acoplado a uma coluna cromatográfica para a separação dos substratos restantes do aduto de Michael na segunda dimensão, seguido por uma coluna de polissacarídeo quiral para a análise de conversão e estereosselectividade. Essa abordagem representa uma nova configuração do instrumento que combina as vantagens de cromatografia multidimensional e reações catálisadas em fluxo.
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Sayer, Lloyd. "A novel approach towards the stereoselective synthesis of inositols and its application in the synthesis of biologically important molecules." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/15658.

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Myo-inositol is ubiquitous in nature and is found at the structural core of a diverse range of biologically important derivatives, including phosphatidylinositols, inositol phosphates and mycothiol. The synthesis of myo-inositol derivatives is notoriously difficult due to the need to control both regio- and enantioselectivity. As a result, synthetic routes to derivatives of this type are often lengthy and low yielding. The first biosynthetic step in the production of all myo-inositol metabolites is the isomerisation of D-glucose 6- phosphate to L-myo-inositol 1-phosphate as mediated by L-myo-inositol 1-phosphate synthase (INO1). For the protozoan parasite Trypanosoma brucei, INO1 is essential for survival and its version of the enzyme (TbINO1) has a high turnover. This makes TbINO1 an attractive candidate for the biocatalytic production of L-myo-inositol 1- phosphate, and a potential starting point for drastically shortened syntheses of important myo-inositol derivatives. The production of L-myo-inositol 1-phosphate by TbINO1 has been optimised to achieve complete conversion in reaction conditions that facilitate product isolation. Due to problems with an in-batch process, the TbINO1 enzyme was immobilised and the process was transferred to a flow system. This has allowed for production of significant quantities of L-myo-inositol 1-phosphate with a high level of purity. L-myo-inositol 1- phosphate obtained from the flow system has been used to prepare mycothiol glycosylation acceptor, 1,2,4,5,6-penta-O-acetyl-D-myo-inositol, in a concise synthesis with a greatly improved yield over the literature.
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Raymond, Justine. "Applications of Flow Chemistry Methods and Computer-Aided Approaches to Expedite the Development of HBV Inhibitors." Doctoral thesis, Universitat Rovira i Virgili, 2021. http://hdl.handle.net/10803/672255.

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L’hepatitis B és una infecció hepàtica greu, i la principal causa de càncer de fetge, causada pel virus de l’hepatitis B (VHB). Tot i que hi ha disponible una vacuna profilàctica, l’hepatitis B continua sent un problema de salut greu. Actualment, les teràpies antivirals aprovades per la FDA es limiten a Interferons de tipus 1 i anàlegs de nucleòs(t)id que redueixen els nivells d’antigen del VHB. En els darrers anys, s’ha identificat una nova classe de compostos anomenats moduladors d’assemblatge de la càpside (CAM) com a agent antiviral, que mostren el potencial d’eliminar eficientment l’ADN del VHB de les cèl·lules hepàtiques infectades. L’objectiu d’aquesta tesi doctoral és el desenvolupament de metodologies innovadores, en fluix continu i impulsades computacionalment, per accelerar el descobriment de nous inhibidors del VHB dins del projecte VIRO-FLOW. Aquests nous processos van facilitar l’obtenció de components d’interès en el desenvolupament d’un nou quimiotip de compostos CAM. A més, també s’ha desenvolupat una ruta eficient per sintetitzar [1,2,4]triazolo-[1,5-a]-piridina-2-carboxamides en flux continuo. S'ha avaluat les limitacions de la reacció i s’ha proporcionat un mecanisme de la reacció mitjançant càlculs DFT. A més, s’han dissenyat i optimitzat rutes sintètiques que combinen processos batch i flux continu per obtenir una nova quimioteca. Mitjançant un estudi de la relació estructura-activitat,
La hepatitis B es una infección hepática grave, y la principal causa de cáncer de hígado, causada por el virus de la hepatitis B (VHB). Aunque se dispone de una vacuna profiláctica, la hepatitis B sigue siendo un problema de salud grave. Actualmente, las terapias antivirales aprobadas por la FDA se limitan a Interferones de tipo 1 y análogos de nucleós(t)idos que reducen los niveles de antígeno del VHB. Recientemente, se ha identificado una nueva clase de compuestos denominados moduladores de ensamblaje de la cápside (CAM) como agente antiviral, que muestra el potencial de eliminar eficazmente el ADN del VHB de las células hepáticas infectadas. El objetivo de esta tesis doctoral es el desarrollo de metodologías novedosas, en flujo continuo y computacionalmente impulsadas, para acelerar el descubrimiento de nuevos inhibidores del VHB dentro del proyecto VIRO-FLOW. Estos nuevos procesos facilitaron la obtención de componentes de interés en el desarrollo de un nuevo quimiotipo de compuestos CAM. Además, también se ha desarrollado una ruta eficaz para sintetizar [1,2,4]triazolo- [1,5-a]-piridina-2-carboxamidas en flujo continuo. Se evaluaron las limitaciones de la reacción y se ha proporcionado una mecanismo de la reacción mediante cálculos DFT. Además, se diseñaron y optimizaron rutas sintéticas que combinan procesos batch y flujo continuo para obtener una nueva quimioteca. Mediante un estudio de la relación estructura-actividad y se identificaron dos compuestos lead. Por otro lado, se creó un método de cribado virtual que combina modelos de farmacóforos y el acoplamiento molecular para priorizar la síntesis de nuevos compuestos, dando como resultado nuevos análogos con mayor actividad que el lead inicial. Finalmente, se utilizó una combinación de dinámica molecular y modelos de farmacóforos para realizar un gran cribado virtual. El método condujo a la selección de treinta moléculas con una excelente relación con fármacos antivirales que serán posteriormente evaluados.
Hepatitis B is a serious liver infection and the primary cause of liver cancer caused by Hepatitis B Virus (HBV). Even though a prophylactic vaccine is available, Hepatitis B remains as a serious health issue. Currently, FDA-approved antiviral therapies are limited to type 1 interferons and nucleos(t)ide analogues which reduce HBV antigen levels. In recent years, a new class of compounds named capsid assembly modulators (CAMs) have been identified as antiviral agent, showing the potential to efficiently eliminate HBV DNA from infected liver cells. This doctoral thesis objective are the development of novel methodologies, in continuous flow and computationally driven, that will support and accelerate the discovery of new HBV inhibitors within the VIRO-FLOW project. These new processes facilitated the obtention of several building blocks of interest in the development of a new HBV CAMs chemotype. Furthermore, an efficient route for the synthesis of 1,2,4-triazolo-[1,5-a]-pyridine-2-carboxylate in continuous flow has been also developed. The limitations of the reaction were assessed, and an acute mechanistic understanding of the reaction process was afforded by DFT calculations. Moreover diversity-oriented synthetic routes combining batch and flow processes were designed and optimized to obtain a focused library of a new compound series. A structure-activity relationship study was conducted, and two compounds were identified as potential lead. On another hand, a virtual screening workflow combining pharmacophore modelling and molecular docking was created to prioritize the synthesis of new analogues in compound series under development, resulting in new analogues with higher activity than the initial lead. Finally, a combination of molecular dynamics and pharmacophore modelling was used to conduct a large virtual screening (ca. 65 million compounds). The method led to the selection of thirty molecules with excellent antiviral drug-likeness to be further evaluated.
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Elsenbeer, Helmut, Daniel Lorieri, and Mike Bonell. "Mixing model approaches to estimate storm flow sources in an overland flow-dominated tropical rain forest catchment." Universität Potsdam, 1995. http://opus.kobv.de/ubp/volltexte/2008/1694/.

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Previous hydrometric studies demonstrated the prevalence of overland flow as a hydrological pathway in the tropical rain forest catchment of South Creek, northeast Queensland. The purpose of this study was to consider this information in a mixing analysis with the aim of identifying sources of, and of estimating their contribution to, storm flow during two events in February 1993. K and acid-neutralizing capacity (ANC) were used as tracers because they provided the best separation of the potential sources, saturation overland flow, soil water from depths of 0.3, 0.6, and 1.2 m, and hillslope groundwater in a two-dimensional mixing plot. It was necessary to distinguish between saturation overland flow, generated at the soil surface and following unchanneled pathways, and overland flow in incised pathways. This latter type of overland flow was a mixture of saturation overland flow (event water) with high concentrations of K and a low ANC, soil water (preevent water) with low concentrations of K and a low ANC, and groundwater (preevent water) with low concentrations of K and a high ANC. The same sources explained the streamwater chemistry during the two events with strongly differing rainfall and antecedent moisture conditions. The contribution of saturation overland flow dominated the storm flow during the first, high-intensity, 178-mm event, while the contribution of soil water reached 50% during peak flow of the second, low-intensity, 44-mm event 5 days later. This latter result is remarkably similar to soil water contributions to storm flow in mountainous forested catchments of the southeastern United States. In terms of event and preevent water the storm flow hydrograph of the high-intensity event is dominated by event water and that of the low-intensity event by preevent water. This study highlights the problems of applying mixing analyses to overland flow-dominated catchments and soil environments with a poorly developed vertical chemical zonation and emphasizes the need for independent hydrometric information for a complete characterization of watershed hydrology and chemistry.
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Keeton, William J. "Analytical Approaches in Investigating the Kinetics of Water-Molecule Complexes in Tropospheric Reactions." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5527.

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Ozone is a heavily monitored pollutant. Ozone is not directly emitted into the atmosphere, but rather the product of chemical reactions. Ground level ozone occurs when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react with each other in the presence of sunlight. The primary precursors of ozone are anthropogenically emitted, and as a result, tropospheric ozone has cost millions of dollars in damages and has hurt the health of countless people. This dissertation is a collection of work that aims to provide insight into atmospheric reactions that result in tropospheric ozone and the instrumentation to study such reactions. While these reactions are well studied, this research is novel in its attempt to understand water vapor's influence in tropospheric ozone reactions. As the troposphere continues to get warmer and wetter from global climate change, water vapor will play a larger role in tropospheric reactions, which in turn may perturb the global reactions. Work is presented on the self-reaction of β-hydroxyethyl peroxy radical (β-HEP), an ozone precursor, and the increase in reaction rate catalyzed by water vapor. β-HEP serves as a model system for understanding the roles of water vapor in perturbing the kinetics and product branching ratio of ozone forming reactions. The self-reaction rate coefficient of β-HEP was investigated between 274-296 K with 1.0 × 1015 to 2.5 × 1017 molecules cm-3 of water vapor at 200 Torr total pressure by slow-flow laser flash photolysis coupled with UV time-resolved spectroscopy and long-path, wavelength-modulated, diode-laser spectroscopy. The overall rate constant is expressed as the product of temperature-dependent and water vapor-dependent terms giving k(T,H2O) = 7.8 × 10-14(e8.2 (±2.5) kJ/RT )(1 + 1.4 × 10-34 × e92 (±11) kJ/RT [H2O]). The results suggest that formation of a β-HEP-H2O complex is responsible for the observed water vapor enhancement of the self-reaction rate coefficient. A new discharge flow mass-spectrometer was engineered in collaboration with the California Institute of Technology and NASA's Jet Propulsion Laboratory. This instrument allows for rapid study of water vapor influence on the kinetics of atmospheric reactions. This instrument will be used in further studying the β-HEP + NO reaction as a function of water vapor concentration.
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Clifford, Dustin M. "Non-Conventional Approaches to Syntheses of Ferromagnetic Nanomaterials." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4205.

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The work of this dissertation is centered on two non-conventional synthetic approaches to ferromagnetic nanomaterials: high-throughput experimentation (HTE) (polyol process) and continuous flow (CF) synthesis (aqueous reduction and the polyol process). HTE was performed to investigate phase control between FexCo1-x and Co3-xFexOy. Exploration of synthesis limitations based on magnetic properties was achieved by reproducing Ms=210 emu/g. Morphological control of FexCo1-x alloy was achieved by formation of linear chains using an Hext. The final study of the FexCo1-x chains used DoE to determine factors to control FexCo1-x, diameter, crystallite size and morphology. [Ag] with [Metal] provide statistically significant control of crystallite size. [OH]/[Metal] predict 100 % FexCo1-x at > 30. To conclude section 1, a morphological study was performed on synthesis of Co3-xFexOy using the polyol process. Co3-xFexOy micropillars were synthesized at various sizes. The close proximity of the particles in the nanostructure produced an optical anisotropy and was magnetically induced which is evidence for the magneto-birefringence effect. The second non-conventional synthetic approach involves continuous flow (CF) chemistry. Co nanoparticles (Ms=125 emu/g) were newly synthesized by aqueous reduction in a microreactor and had 30 ±10 nm diameter and were produced at >1g/hr, a marker of industrial-scale up viability. The final work was the CF synthesis of FexCo1-x. The FexCo1-x was synthesized with limitation to the composition. The maximum FexCo1-x phase composition at 20 % resulted from the aqueous carrier solvent triggering oxide formation over FexCo1-x.
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Flack, Kyle M. "Two approaches to green chemistry in industrially driven processes: aluminum tert-butoxide as a rate enhancing Meerwein-Ponndorf-Verley reduction catalyst applied to the technological transfer from batch to continuous flow and structural modifications of functionalized trialkylsilylamines as energy efficient carbon dioxide capture solvents." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44802.

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Green chemistry principles have been applied to the enhancement of two industrial chemistry problems. An industrially used reaction to form alcohols from aldehydes and ketones, the Meerwein-Ponndorf-Verley reduction, was improved by introducing a new catalyst Al(OtBu)₃. Due to the lower state of aggregation of this catalyst versus the conventional Al(OiPr)₃ catalyst, reduction rates were found to be faster in both pure iPrOH and mixed solvent systems for three model compounds: benzaldehyde, acetophenone, and a complex, chiral ketone, (S)-CMK. This allowed for the successful implementation of two important milestones; lowering the amount of catalyst needed necessary to complete the reactions (an economic benefit and lower waste) and the conversion from traditional batch reactions to continuous flow (a processing benefit) whereby reactions can be scaled-out rather than scaled-up. Another industrially important field of research that was focused on was CO₂ capture. High energy demands from current CO₂ capture methods such as aqueous amine solvents, specifically from coal-fired power plant flue gas, led to the development of non-aqueous reversible ionic liquids based on silylated amines. Structural modifications of the substitution around the silicon atom, the length of the alkyl chain bonding the silicon and amine, branching along the alkyl backbone, and investigating secondary and primary amines within this class of silylated amines were completed. These amines were reacted with CO₂ and the CO₂ capacity, the ionic liquid viscosity, reversal temperature and reaction enthalpy were all considered as a function of structure. In all cases the capacity was found to be not only greater than that of monethanolamine, an industrial standard, but higher than theoretical predictions through the formation of carbamic acid. Viscosity, reversal temperature, and reaction enthalpy were all found to be tunable through structure. These modifications gave significant insight into the necessary direction for optimization of these solvents as energy-efficient replacements of current CO₂ capture technology.
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Books on the topic "Flow chemistry approach"

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Scudder, Paul H. Electron Flow in Organic Chemistry: A Critical Thinking Approach to Organic Mechanisms. Wiley & Sons, Limited, John, 2022.

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Flow Chemistry: Integrated Approaches for Practical Applications. Royal Society of Chemistry, The, 2019.

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Garcia-Verdugo, Eduardo, and Santiago V. Luis. Flow Chemistry: Integrated Approaches for Practical Applications. Royal Society of Chemistry, The, 2019.

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Garcia-Verdugo, Eduardo, and Santiago V. Luis. Flow Chemistry: Integrated Approaches for Practical Applications. Royal Society of Chemistry, The, 2019.

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Binetruy, Christophe, Francisco Chinesta, and Roland Keunings. Flows in Polymers, Reinforced Polymers and Composites: A Multi-Scale Approach. Springer London, Limited, 2015.

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Flows in Polymers, Reinforced Polymers and Composites: A Multi-Scale Approach. Springer International Publishing AG, 2015.

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Book chapters on the topic "Flow chemistry approach"

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Popp, Sebastian, Steffen Weise, and Christian Hasse. "A Novel Approach for Efficient Storage and Retrieval of Tabulated Chemistry in Reactive Flow Simulations." In Lecture Notes in Computer Science, 82–95. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-53862-4_8.

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Hale, Robert C., Meredith E. Seeley, Ashley E. King, and Lehuan H. Yu. "Analytical Chemistry of Plastic Debris: Sampling, Methods, and Instrumentation." In Microplastic in the Environment: Pattern and Process, 17–67. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-78627-4_2.

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AbstractApproaches for the collection and analysis of plastic debris in environmental matrices are rapidly evolving. Such plastics span a continuum of sizes, encompassing large (macro-), medium (micro-, typically defined as particles between 1 μm and 5 mm), and smaller (nano-) plastics. All are of environmental relevance. Particle sizes are dynamic. Large plastics may fragment over time, while smaller particles may agglomerate in the field. The diverse morphologies (fragment, fiber, sphere) and chemical compositions of microplastics further complicate their characterization. Fibers are of growing interest and present particular analytical challenges due to their narrow profiles. Compositional classes of emerging concern include tire wear, paint chips, semisynthetics (e.g., rayon), and bioplastics. Plastics commonly contain chemical additives and fillers, which may alter their toxicological potency, behavior (e.g., buoyancy), or detector response (e.g., yield fluorescence) during analysis. Field sampling methods often focus on >20 μm and even >300 μm sized particles and will thus not capture smaller microplastics (which may be most abundant and bioavailable). Analysis of a limited subgroup (selected polymer types, particle sizes, or shapes) of microplastics, while often operationally necessary, can result in an underestimation of actual sample content. These shortcomings complicate calls for toxicological studies of microplastics to be based on “environmentally relevant concentrations.” Sample matrices of interest include water (including wastewater, ice, snow), sediment (soil, dust, wastewater sludge), air, and biota. Properties of the environment, and of the particles themselves, may concentrate plastic debris in select zones (e.g., gyres, shorelines, polar ice, wastewater sludge). Sampling designs should consider such patchy distributions. Episodic releases due to weather and anthropogenic discharges should also be considered. While water grab samples and sieving are commonplace, novel techniques for microplastic isolation, such as continuous flow centrifugation, show promise. The abundance of nonplastic particulates (e.g., clay, detritus, biological material) in samples interferes with microplastic detection and characterization. Their removal is typically accomplished using a combination of gravity separation and oxidative digestion (including strong bases, peroxide, enzymes); unfortunately, aggressive treatments may damage more labile plastics. Microscope-based infrared or Raman detection is often applied to provide polymer chemistry and morphological data for individual microplastic particles. However, the sheer number of particles in many samples presents logistical hurdles. In response, instruments have been developed that employ detector arrays and rapid scanning lasers. The addition of dyes to stain particulates may facilitate spectroscopic detection of some polymer types. Most researchers provide microplastic data in the form of the abundances of polymer types within particle size, polymer, and morphology classes. Polymer mass data in samples remain rare but are essential to elucidating fate. Rather than characterizing individual particles in samples, solvent extraction (following initial sample prep, such as sediment size class sorting), combined with techniques such as thermoanalysis (e.g., pyrolysis), has been used to generate microplastic mass data. However, this may obviate the acquisition of individual particle morphology and compositional information. Alternatively, some techniques (e.g., electron and atomic force microscopy and matrix-assisted laser desorption mass spectrometry) are adept at providing highly detailed data on the size, morphology, composition, and surface chemistry of select particles. Ultimately, the analyst must select the approach best suited for their study goals. Robust quality control elements are also critical to evaluate the accuracy and precision of the sampling and analysis techniques. Further, improved efforts are required to assess and control possible sample contamination due to the ubiquitous distribution of microplastics, especially in indoor environments where samples are processed.
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de Souza, Rodrigo O. M. A. "Industrial Approaches Toward API Synthesis Under Continuous-Flow Conditions." In Topics in Heterocyclic Chemistry, 375–89. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/7081_2018_25.

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Santoro, S., F. Ferlin, and L. Vaccaro. "Chapter 6. Sustainable Approaches to C–H Functionalizations Through Flow Techniques." In Green Chemistry Series, 199–216. Cambridge: Royal Society of Chemistry, 2019. http://dx.doi.org/10.1039/9781788016094-00199.

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Baumann, Marcus, and Ian R. Baxendale. "Flow Chemistry Approaches Applied to the Synthesis of Saturated Heterocycles." In Topics in Heterocyclic Chemistry, 187–236. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/7081_2018_16.

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Brocken, Laurens, and Ian R. Baxendale. "Chapter 8. Ionic Polymerisation and New Approaches to Polymerisation under Flow Conditions." In Green Chemistry Series, 257–315. Cambridge: Royal Society of Chemistry, 2019. http://dx.doi.org/10.1039/9781788016094-00257.

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Baru, Michael B., Irina A. Peshenko, Ludmila N. Rodionova, and Igor L. Rodionov. "A comparative study of swellographic and spectrophotometric approaches to monitoring of continuous-flow Fmoc-SPPS." In Peptide Chemistry 1992, 116–18. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1474-5_34.

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Taber, Douglass F. "Flow Chemistry." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0018.

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Arturo Macchi of the University of Ottawa and Dominique M. Roberge of Lonza sum­marized (Org. Process Res. Dev. 2014, 18, 1286) a “toolbox approach” for the evolution from batch to continuous chemical synthesis. Michael D. Organ of York University developed (Org. Process Res. Dev. 2014, 18, 1315) a flow reactor with inline analyt­ics, and Timothy D. White of Eli Lilly described (Org. Process Res. Dev. 2014, 18, 1482) the continuous production of solid products under flow conditions. Electrochemical reduction and oxidation are particularly easy under flow conditions. Steven V. Ley of the University of Cambridge oxidized (Org. Lett. 2014, 16, 4618) 1 under flow conditions, then condensed the product with tryptamine 2 to pre­pare the indole alkaloid Nazlinine 3. Thomas Wirth of Cardiff University electrolyzed (Org. Process Res. Dev. 2014, 18, 1377) the carbonate 4 in a non-divided cell to return the deprotected phenol 5. Timothy Noël of the Eindhoven University of Technology gathered (Chem. Eur. J. 2014, 20, 10562) an overview of photochemical transformations under flow condi­tions. Kevin I. Booker-Milburn of the University of Bristol observed (Chem. Eur. J. 2014, 20, 15226) superior yields for the coupling of 6 with 7 to form 8 under flow compared to batch conditions. Koichi Fukase of Osaka University and Ilhyong Ryu of Osaka Prefecture University converted (Chem. Eur. J. 2014, 20, 12750) 9 selectively to 10 under flow conditions. Alexei A. Lapkin, also of the University of Cambridge, optimized (Org. Process Res. Dev. 2014, 18, 1443) the singlet oxygen conversion of 11 to 12. Shawn K. Collins of the Université de Montréal cyclized (Org. Process Res. Dev. 2014, 18, 1571) 13 to 14. There have been several advances in the use of enzymes under flow conditions. Rodrigo O. M. A. de Souza of the Federal University of Rio de Janeiro found (Org. Process Res. Dev. 2014, 18, 1372) that lipase in a microemulsion-based organogel efficiently converted coupled 15 with 16 to make 17. Timothy F. Jamison of MIT developed (Org. Lett. 2014, 16, 6092) a catch-and-release protocol for the reductive amination of 18 with 19 to give 20.
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Basavaraju, Girish, Y. Ashwin, Prathyusha Naini, and Ravishankar Rajanna. "Process Intensification in the Customized Flow Reactors." In Recent Advances in Chemical Kinetics. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.101703.

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The development and intensification of flow reactors are emerging as a new niche area in the pharmaceutical process development. However, development without adequate knowledge of chemistry, kinetics, mass and heat transfer, equipment design, residence time and residence time distribution (RTD) aspects could be difficult to realize the true potential of flow processing development. Understanding these aspects would enable the experimenter to explore options, troubleshoot, and find insights into a wide array of possibilities for continuous flow chemistry development and scaleup. The study provides a systematic approach for flow process development, insights to characterize the equipment, optimize the conditions, and derive meaningful conclusions. The results are presented through appropriate tables and charts to understand the concepts and apply them for various processes. As a case study, a well-known saponification reaction was subjected to represent the performance of the batch versus the flow process (packed bed reactor and tubular reactor) and listed advantages.
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Ma, Liang, Cheng Huang, and Zhong-Sheng Liu. "The Application of Artificial Neural Network to Predicting the Drainage from Waste Rock Storages." In Deep Learning Applications. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96162.

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Reliable prediction of drainage flow rate and drainage chemistry is essential to the treatment of drainage from waste rock storages at mine sites. The traditional predictive models require simplification and assumption of geo-bio-chemical processes followed by intensive characterization, and sometimes lead to poor prediction accuracy. In the big data era, various sensors are installed in field to constantly monitor mine sites, which enables machine learning to utilize the generated monitoring data and study the underlying pattern behind the data. This chapter describes an approach to use artificial neural network to predict the drainage flow rate and drainage chemistry based on weather monitoring data collected at mine sites. The advantage of this approach is that generally no additional characterization are required to make prediction because the relevant geo-bio-chemical mechanisms are embedded naturally in the monitoring data, which can be captured through machine learning process.
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Conference papers on the topic "Flow chemistry approach"

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Savre, Julien, Nicolas Bertier, Daniel Gaffie, and Yves D'Angelo. "LEAN PREMIXED TURBULENT COMBUSTION MODELING USING FLAME TABULATED CHEMISTRY AND A PRESUMED PDF APPROACH." In Sixth International Symposium on Turbulence and Shear Flow Phenomena. Connecticut: Begellhouse, 2009. http://dx.doi.org/10.1615/tsfp6.680.

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Alwazzan, Amir, Maryam Dashtebayaz, and Mohamed Fiaz. "From Pore to Process: Novel Flow Assurance Approach to Suppress Severe Production Chemistry Issues by Flow Dynamic Characterization." In SPE Middle East Oil and Gas Show and Conference. Society of Petroleum Engineers, 2019. http://dx.doi.org/10.2118/194768-ms.

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Hamouda, A. A., and S. Davidsen. "An Approach for Simulation of Paraffin Deposition in Pipelines as a Function of Flow Characteristics With a Reference to Teesside Oil Pipeline." In SPE International Symposium on Oilfield Chemistry. Society of Petroleum Engineers, 1995. http://dx.doi.org/10.2118/28966-ms.

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Liu, Xinghui, and Faruk Civan. "Formation Damage by Fines Migration Including Effects of Filter Cake, Pore Compressibility, and Non-Darcy Flow - A Modeling Approach to Scaling From Core to Field." In SPE International Symposium on Oilfield Chemistry. Society of Petroleum Engineers, 1995. http://dx.doi.org/10.2118/28980-ms.

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Drennan, Scott A., Chen-Pang Chou, Anthony F. Shelburn, Devin W. Hodgson, Cheng Wang, Chitralkumar V. Naik, Ellen Meeks, and Hasan Karim. "Flow Field Derived Equivalent Reactor Networks for Accurate Chemistry Simulation in Gas Turbine Combustors." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59861.

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A method has been developed in which the flow field predicted by Computational Fluid Dynamics (CFD) is automatically condensed into an Equivalent Reactor Network (ERN), composed of well stirred reactors, allowing rapid and accurate analysis of emissions. This paper presents the effectiveness of utilizing an ERN that is a direct abstraction of the computational flow field for combustion analysis. The CFD results are divided into reactors using various filters on flow-field variables to construct an ERN that represents the 3-D combustor flow field and flame structure. Detailed kinetics can then be used in ERN simulations to analyze effects of fuel composition and operating condition on emissions. The technique is applied to a commercial industrial gas turbine combustor fuel injector and compared against experimental emissions results. Sensitivity of emissions predictions to different parameters in the network extraction is also presented. Parameter variations in fuel flow rate are applied to the ERN to obtain relative impacts of fuel-air ratio on the emissions of NOx without requiring new CFD solutions. This automatic approach has been found to reduce the time required to construct and analyze flow field derived ERNs with detailed chemistry by 90%. A local calculation of Damko¨hler number, important for stability analysis, is also presented. This calculation also uses abstracted information from the CFD flow field and detailed-kinetics simulations for more accurate, cost-effective analysis.
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Chow, S. K., and J. J. McGuirk. "Numerical Prediction of Flow and Combustion Characteristics of a Model Annular Combustor." In ASME 1991 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1991. http://dx.doi.org/10.1115/91-gt-364.

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Two instantaneous chemistry descriptions (full chemical equilibrium and laminar flamelet) were applid to the prediction of gaseous reaction in a small-scale combustor. The chemical state relationships were combined with a single conserved scalar/β-function pdf/k-ε turbulence model closure. Encouraging results were obtained for the flowfield and conserved scalar distributions, although only when the jet entry boundary conditions were altered to accord closely with several expected experimental features. These predictions imply that any acceptable approach to combustor modelling must extend calculations to include the outer annulus. Exit temperature levels were predicted fairly well, but the quality of internal distributions deteriorated due to errors in predicted fuel/air mixing. Differences between the two chemistry models were small except for CO and H2 species concentrations where the flamelet model gave better agreement with experiments.
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Barz, Dominik P. J., and Peter Ehrhard. "Fully-Coupled Modelling of Electrokinetic Flow and Migration of Electrolytes in Microfluidic Devices." In ASME 2007 5th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2007. http://dx.doi.org/10.1115/icnmm2007-30117.

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We investigate the electrokinetic flow and mass transport in a microchannel junction, serving as an injector of a microelectrophoresis device. In order to consider all essential features of this complex system, the electrical situation, the fluid dynamics, and the (physical) chemistry is taken into account. The electrical situation is modeled by a combination of an electrostatic and an electrodynamic approach. The fluid dynamics can be described by the Navier-Stokes equations, extended by an additional force term. The chemistry of the system is represented by source terms in the mass transport equations. Moreover, the interaction between the buffer concentration and the physicochemical properties of the channel wall is taken into consideration by an empirical approach. All equations are encoded in a dimensionless form so that dimensionless groups control the problem. Approximative analytical solutions for the phenomena within the electrical double layer can be found and, thus, we can reduce the numerical costs due to an asymptotic matching procedure. The models are implemented in a Finite Element Method (FEM) code and time-dependent, two-dimensional simulations are performed. The results of the simulations show the strong coupling between the involved physicochemical processes.
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Lee, Changgu, and Luc G. Fre´chette. "Analytical Solution of the Flow Along Parallel Microchannels Separated by a Porous Membrane." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-33625.

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This papers presents the analytical solution of the flow distribution along a porous membrane which is between two parallel microchannels, a configuration of increasing importance in microsystems for DNA sequencing, catalytic chemistry, and in micro heat exchangers. The modeling approach presented in the paper is inspired from thin film lubrication theory and would be applicable for a wide range of low Reynolds number, pressure-driven microfluidic configurations.
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Bankhead, Mark, Kevin Good, Scott L. Owens, and Karl P. Travis. "Multi-Scale Simulation of Soft Material Flow." In ASME 2006 Pressure Vessels and Piping/ICPVT-11 Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/pvp2006-icpvt-11-93173.

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We describe a multi-scale modeling approach to model the rheology of soft matter, which can then be applied to simulate flow of viscous inorganic material in pipes and containers. Mesoscale methods, such as dissipative particle dynamics (DPD) are a key component of multi-scale modeling, as they bridge the gap between fundamental theory and continuum length scales. The paper describes a method for parameterizing DPD simulations for cements and inorganic sludges based on calculating a volume dependent cohesive energy interaction and compressive term from MD simulation with a generalized inorganic forcefield. By modifying the fluid properties through the interaction parameters one can simulate change of chemistry, such as pH or the introduction of chemicals to improve flow properties (super-plasticizers). Parameters obtained from mesoscale simulation can then be applied to simulate flow of soft matter inside pipes and containers using traditional CFD techniques. Two potential future applications in the nuclear industry are discussed in the areas of waste retrieval and encapsulation.
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Ayazi, Philip, Nathan Peregoy, Gabriel Monreal, and Frank Zamora. "Screening Friction Reducer Performance Using Zeta Potential." In SPE International Conference on Oilfield Chemistry. SPE, 2021. http://dx.doi.org/10.2118/204303-ms.

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Abstract Friction reducers (FRs) are essential additives for water used in hydraulic fracturing treatments for shale reservoirs. These polymers swell and unfurl in the frac water so that polymer chains align along the direction of flow to inhibit turbulence thereby reducing friction at high flow rates. Source water ion content, application pH, and compatibility with the formation are key drivers in deciding which FR chemistries are fit-for-purpose for the operation, balancing desired fluid performance with treatment economics. This investigation explores zeta potential measurement as a novel and meaningful analytical metric to correlate chemical and rheological properties of FRs in a range of source water qualities with their friction reducing performance. The approach of this investigation involves measuring zeta potential of frac fluids formulated using anionic or cationic FRs in waters with varying ionic activity over a range of FR concentrations and pH. The evaluation encompasses a variety of FRs spanning general purpose materials to more sophisticated additives designed to function in fluids with higher concentrations of salt. Dry FR materials as well as corresponding slurry or emulsion forms of the additives are tested. Monovalent and divalent salts and mixtures thereof are used in brine formulations. FR characterization is performed including rheological sweeps, viscoelasticity measurements, and flow loop tests. Results from this study support the conclusion that zeta potential measurement can be used during the FR screening process as a viable supplement to industry standard tests for assessing FR performance in brine.
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Reports on the topic "Flow chemistry approach"

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Dudley, Lynn M., Uri Shani, and Moshe Shenker. Modeling Plant Response to Deficit Irrigation with Saline Water: Separating the Effects of Water and Salt Stress in the Root Uptake Function. United States Department of Agriculture, March 2003. http://dx.doi.org/10.32747/2003.7586468.bard.

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Standard salinity management theory, derived from blending thermodynamic and semi- empirical considerations leads to an erroneous perception regarding compensative interaction among salinity stress factors. The current approach treats matric and osmotic components of soil water potential separately and then combines their effects to compute overall response. With deficit water a severe yield decrease is expected under high salinity, yet little or no reduction is predicted for excess irrigation, irrespective of salinity level. Similarly, considerations of competition between chloride and nitrate ions have lead to compensation hypothesis and to application of excess nitrate under saline conditions. The premise of compensative interaction of growth factors behind present practices (that an increase in water application alleviates salinity stress) may result in collateral environmental damage. Over-irrigation resulting in salinization and elevated ground water threatens productivity on a global scale. Other repercussions include excessive application of nitrate to compensate for salinity, unwillingness to practice deficit irrigation with saline water, and under-utilization of marginal water. The objectives for the project were as follows: 1) To develop a database for model parameterization and validation by studying yield and transpiration response to water availability, excessive salinity and salt composition. 2) To modify the root sink terms of an existing mechanism-based model(s) of water flow, transpiration, crop yield, salt transport, and salt chemistry. 3) To develop conceptual and quantitative models of ion uptake that considers the soil solution concentration and composition. 4) To develop a conceptual and quantitative models of effects of NaCl and boron accumulation on yield and transpiration. 5) To add a user interface to the water flow, transpiration, crop yield, salt transport, chemistry model to make it easy for others to use. We conducted experiments in field plots and lysimeters to study biomass production and transpiration of com (Zeamays cv. Jubilee), melon (Cucumismelo subsp. melo cv. Galia), tomato (Lycopersiconesculentum Mill. cv. 5656), onion (Alliumcepa L. cv. HA 944), and date palms (Phoenix Dactylifera L. cv. Medjool) under salinity combined with water or with nitrate (growth promoters) or with boron (growth inhibitor). All factors ranged from levels not limiting to plant function to severe inhibition. For cases of combined salinity with water stress, or excess boron, we observed neither additive nor compensative effects on plant yield and transpiration. In fact, yield and transpiration at each combination of the various factors were primarily controlled by one of them, the most limiting factor to plant activity. We proposed a crop production model of the form Yr = min{gi(xi), where Yr = Yi ym-1 is relative yield,Ym is the maximum yield obtained in each experiment, Xi is an environmental factor, gi is a piecewise-linear response function, Yi is yield of a particular treatment. We selected a piecewise-linear approach because it highlights the irrigation level where the response to one factor ceases and a second factor begins. The production functions generate response "envelopes" containing possible yields with diagonal lines represent response to Xi alone and the lines parallel to the X-axis represent response to salinity alone. A multiplicative model was also derived approximating the limiting behaviour for incorporation in a hydrochemical model. The multiplicative model was selected because the response function was required to be continuous. The hydrochemical model was a better predictor of field-measured water content and salt profiles than models based on an additive and compensative model of crop response to salinity and water stress.
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