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Academic literature on the topic 'PFFC'

Author: Grafiati

Published: 4 June 2021

Last updated: 15 February 2022

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Journal articles on the topic "PFFC"

1

Chakraborty, Chanchal, Manas Kumar Bera, Utpal Rana, and Sudip Malik. "Vice versa donor acceptor fluorene–ferrocene alternate copolymer: a twisted ribbon for electrical switching." Chemical Communications 51, no. 66 (2015): 13123–26. http://dx.doi.org/10.1039/c5cc04275e.

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VARADHARAJAN, Sundaramurthy, B. K. Chandrashekar SAGAR, Pundi N. RANGARAJAN, and Govindarajan PADMANABAN. "Localization of ferrochelatase in Plasmodium falciparum." Biochemical Journal 384, no. 2 (November 23, 2004): 429–36. http://dx.doi.org/10.1042/bj20040952.

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Our previous studies have demonstrated de novo haem biosynthesis in the malarial parasite (Plasmodium falciparum and P. berghei). It has also been shown that the first enzyme of the pathway is the parasite genome-coded ALA (δ-aminolaevulinate) synthase localized in the parasite mitochondrion, whereas the second enzyme, ALAD (ALA dehydratase), is accounted for by two species: one species imported from the host red blood cell into the parasite cytosol and another parasite genome-coded species in the apicoplast. In the present study, specific antibodies have been raised to PfFC (parasite genome-coded ferrochelatase), the terminal enzyme of the haem-biosynthetic pathway, using recombinant truncated protein. With the use of these antibodies as well as those against the hFC (host red cell ferrochelatase) and other marker proteins, immunofluorescence studies were performed. The results reveal that P. falciparum in culture manifests a broad distribution of hFC and a localized distribution of PfFC in the parasite. However, PfFC is not localized to the parasite mitochondrion. Immunoelectron-microscopy studies reveal that PfFC is indeed localized to the apicoplast, whereas hFC is distributed in the parasite cytoplasm. These results on the localization of PfFC are unexpected and are at variance with theoretical predictions based on leader sequence analysis. Biochemical studies using the parasite cytosolic and organellar fractions reveal that the cytosol containing hFC accounts for 80% of FC enzymic activity, whereas the organellar fraction containing PfFC accounts for the remaining 20%. Interestingly, both the isolated cytosolic and organellar fractions are capable of independent haem synthesis in vitro from [4-14C]ALA, with the cytosol being three times more efficient compared with the organellar fraction. With [2-14C]glycine, most of the haem is synthesized in the organellar fraction. Thus haem is synthesized in two independent compartments: in the cytosol, using the imported host enzymes, and in the organellar fractions, using the parasite genome-coded enzymes.

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Watson, P. D., and M. B. Wolf. "Filtration coefficient in cat hindlimb using protein concentration changes." American Journal of Physiology-Heart and Circulatory Physiology 256, no. 1 (January 1, 1989): H186—H194. http://dx.doi.org/10.1152/ajpheart.1989.256.1.h186.

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The maximum value of capillary filtration coefficient (CFC) in maximally vasodilated cat skeletal muscle is disputed. It was hypothesized that the wide range of reported values was caused by the inability of gravimetric and volumetric measurements of tissue volume to separate transcapillary filtration from vascular volume changes. Consequently, we developed a method of measuring filtration rates from changes in venous protein concentration using Evan's blue-labeled albumin in the isolated hindlimb (pentobarbital sodium anesthesia). The filtration coefficient (PFFC) calculated from these filtration rates after a step in venous pressure should not be influenced by vascular volume changes. When the perfusate flow rate through the hindlimb was greater than 15 ml.min-1.100 g muscle-1, PFFC was 0.0085 +/- 0.0015 (SD, n = 8) ml.min-1.mmHg-1.100 g muscle-1. PFFC was observed to be unvarying from 1 to 12 min after the venous pressure elevation, in contrast to CFC values, which fall during the same period. It is argued that the difference between CFC and PFFC values is caused by vascular volume changes.

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Bonnet, Suzanna Maria, Claudine Pereira Dereczynski, and Ana Nunes. "Caracterização Sinótica e Climatológica de Eventos de Chuva Pós-Frontal no Rio de Janeiro." Revista Brasileira de Meteorologia 33, no. 3 (September 2018): 547–57. http://dx.doi.org/10.1590/0102-7786333013.

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Resumo No Município do Rio de Janeiro (MRJ), verifica-se em certas situações de deslocamento de Sistemas Frontais (SFs), a ocorrência de chuvas fracas a moderadas, mesmo após a completa passagem do SF pelo Estado. Este fenômeno é conhecido na região como precipitação devido ao “efeito de circulação marítima”, mas não apresenta documentação, ficando restrito ao conhecimento dos previsores locais. O objetivo deste trabalho é elaborar uma climatologia da frequência de ocorrência desse fenômeno no MRJ para o período 2000-2013 e identificar as condições sinóticas associadas. A partir de imagens de satélite e dados de precipitação, as passagens de SFs pelo MRJ foram classificadas em três tipos: Pós-Frontais Sem Chuva (PFSC); Pós-Frontais Com Chuva (PFCC) e Pós-Frontais Excluídos (PFE). Os resultados indicam que mais da metade dos eventos são do tipo PFE (52%), 32% do tipo PFSC e 16% do tipo PFCC. Os casos PFE predominam no verão, os PFSC no inverno e primavera e os PFCC no outono. Os compostos dos casos PFSC e PFCC utilizando a Reanálise ERA-Interim indicam que a precipitação pós-frontal estaria associada à convergência de fortes ventos de sul junto à costa ao penetrar no continente, formando nuvens estratiformes, apesar do SF não estar mais atuando.

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Zhang, Qi, Yue Xu, Juhyung Lee, Michal Jarnik, Xufeng Wu, Juan S. Bonifacino, Jingshi Shen, and Yihong Ye. "A myosin-7B–dependent endocytosis pathway mediates cellular entry of α-synuclein fibrils and polycation-bearing cargos." Proceedings of the National Academy of Sciences 117, no. 20 (May 4, 2020): 10865–75. http://dx.doi.org/10.1073/pnas.1918617117.

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Cell-to-cell transmission of misfolding-prone α-synuclein (α-Syn) has emerged as a key pathological event in Parkinson’s disease. This process is initiated when α-Syn–bearing fibrils enter cells via clathrin-mediated endocytosis, but the underlying mechanisms are unclear. Using a CRISPR-mediated knockout screen, we identify SLC35B2 and myosin-7B (MYO7B) as critical endocytosis regulators for α-Syn preformed fibrils (PFFs). We show that SLC35B2, as a key regulator of heparan sulfate proteoglycan (HSPG) biosynthesis, is essential for recruiting α-Syn PFFs to the cell surface because this process is mediated by interactions between negatively charged sugar moieties of HSPGs and clustered K-T-K motifs in α-Syn PFFs. By contrast, MYO7B regulates α-Syn PFF cell entry by maintaining a plasma membrane-associated actin network that controls membrane dynamics. Without MYO7B or actin filaments, many clathrin-coated pits fail to be severed from the membrane, causing accumulation of large clathrin-containing “scars” on the cell surface. Intriguingly, the requirement for MYO7B in endocytosis is restricted to α-Syn PFFs and other polycation-bearing cargos that enter cells via HSPGs. Thus, our study not only defines regulatory factors for α-Syn PFF endocytosis, but also reveals a previously unknown endocytosis mechanism for HSPG-binding cargos in general, which requires forces generated by MYO7B and actin filaments.

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Jarvela, Timothy S., Kriti Chaplot, and Iris Lindberg. "A protease protection assay for the detection of internalized alpha-synuclein pre-formed fibrils." PLOS ONE 16, no. 1 (January 26, 2021): e0241161. http://dx.doi.org/10.1371/journal.pone.0241161.

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Alpha-synuclein pre-formed fibrils (PFFs) represent a promising model system for the study of cellular processes underlying cell-to-cell transmission of alpha-synuclein proteopathic aggregates. However, the ability to differentiate the fate of internalized PFFs from those which remain in the extracellular environment remains limited due to the propensity for PFFs to adhere to the cell surface. Removal of PFFs requires repeated washing and/or specific quenching of extracellular fluorescent PFF signals. In this paper we present a new method for analyzing the fate of internalized alpha-synuclein. We inserted a tobacco etch virus (TEV) protease cleavage site between alpha-synuclein and green fluorescent protein and subjected cells to brief treatment with TEV protease after incubation with tagged PFFs. As the TEV protease is highly specific, non-toxic, and active under physiological conditions, protection from TEV cleavage can be used to distinguish internalized PFFs from those which remain attached to the cell surface. Using this experimental paradigm, downstream intracellular events can be analyzed via live or fixed cell microscopy as well as by Western blotting. We suggest that this method will be useful for understanding the fate of PFFs after endocytosis under various experimental manipulations.

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Rao, Raghavendra, Srilatha Parampalli Srinivas, and Varsha M. Shetty. "A case of Giant Perifollicular Fibroma - a Diagnostic Challenge." Serbian Journal of Dermatology and Venereology 12, no. 1 (March 1, 2020): 19–21. http://dx.doi.org/10.2478/sjdv-2020-0004.

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AbstractPerifollicular fibroma (PFF) is a rare proliferative lesion originating from the perifollicular connective tissue sheath. It may be congenital or acquired manifesting as skin colored to pink, asymptomatic papules of 1-5 mm in size. They are commonly distributed in the head and neck region. Multiple PFFs may be associated with internal malignancy or as a part of Birt-Hogg-Dube syndrome. Histopathology serves as an essential tool in clinching the diagnosis. Herein we report a case of giant congenital PFF.

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Jain, Sameer, Ganesh Mohrir, Oliver Townsend, Jonathan N. Lamb, Jeya Palan, Joseph Aderinto, and Hemant Pandit. "Reliability and validity of the Unified Classification System for postoperative periprosthetic femoral fractures around cemented polished taper-slip stems." Bone & Joint Journal 103-B, no. 8 (August 1, 2021): 1339–44. http://dx.doi.org/10.1302/0301-620x.103b8.bjj-2021-0021.r1.

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Aims This aim of this study was to assess the reliability and validity of the Unified Classification System (UCS) for postoperative periprosthetic femoral fractures (PFFs) around cemented polished taper-slip (PTS) stems. Methods Radiographs of 71 patients with a PFF admitted consecutively at two centres between 25 February 2012 and 19 May 2020 were collated by an independent investigator. Six observers (three hip consultants and three trainees) were familiarized with the UCS. Each PFF was classified on two separate occasions, with a mean time between assessments of 22.7 days (16 to 29). Interobserver reliability for more than two observers was assessed using percentage agreement and Fleiss’ kappa statistic. Intraobserver reliability between two observers was calculated with Cohen kappa statistic. Validity was tested on surgically managed UCS type B PFFs where stem stability was documented in operation notes (n = 50). Validity was assessed using percentage agreement and Cohen kappa statistic between radiological assessment and intraoperative findings. Kappa statistics were interpreted using Landis and Koch criteria. All six observers were blinded to operation notes and postoperative radiographs. Results Interobserver reliability percentage agreement was 58.5% and the overall kappa value was 0.442 (moderate agreement). Lowest kappa values were seen for type B fractures (0.095 to 0.360). The mean intraobserver reliability kappa value was 0.672 (0.447 to 0.867), indicating substantial agreement. Validity percentage agreement was 65.7% and the mean kappa value was 0.300 (0.160 to 0.4400) indicating only fair agreement. Conclusion This study demonstrates that the UCS is unsatisfactory for the classification of PFFs around PTS stems, and that it has considerably lower reliability and validity than previously described for other stem types. Radiological PTS stem loosening in the presence of PFF is poorly defined and formal intraoperative testing of stem stability is recommended. Cite this article: Bone Joint J 2021;103-B(8):1339–1344.

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Roux, Amandine, Xinhe Wang, Katelyn Becker, and Jiyan Ma. "Modeling α-Synucleinopathy in Organotypic Brain Slice Culture with Preformed α-Synuclein Amyloid Fibrils." Journal of Parkinson's Disease 10, no. 4 (October 27, 2020): 1397–410. http://dx.doi.org/10.3233/jpd-202026.

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Background: Synucleinopathy is a group of neurodegenerative disorders characterized by neurodegeneration and accumulation of alpha-synuclein (α-syn) aggregates in various brain regions. The detailed mechanism of α-syn-caused neurotoxicity remains obscure, which is partly due to the lack of a suitable model that retains the in vivo three-dimensional cellular network and allows a convenient dissection of the neurotoxic pathways. Recent studies revealed that the pre-formed recombinant α-syn amyloid fibrils (PFFs) induce a robust accumulation of pathogenic α-syn species in cultured cells and animals. Objective: Our goal is to determine whether PFFs are able to induce the pathogenic α-syn accumulation and neurotoxicity in organotypic brain slice culture, an ex vivo system that retains the in vivo three-dimensional cell-cell connections. Methods/Results: Adding PFFs to cultured wild-type rat or mouse brain slices induced a time-dependent accumulation of pathogenic α-syn species, which was indicated by α-syn phosphorylated at serine 129 (pα-syn). The PFF-induced pα-syn was abolished in brain slices prepared from α-syn null mice, suggesting that the pα-syn is from the phosphorylation of endogenous α-syn. Human PFFs also induced pα-syn in brain slices prepared from mice expressing human α-syn on a mouse α-syn-null background. Furthermore, the synaptophysin immunoreactivity was inversely associated with pα-syn accumulation and an increase of neuronal loss was detected. Conclusion: PFF-treatment of brain slices is able to induce key pathological features of synucleinopathy: pα-syn accumulation and neurotoxicity. This model will be useful for investigating the neurotoxic mechanism and evaluating efficacy of therapeutic approaches.

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Boutros, Sydney Weber, Jacob Raber, and Vivek K. Unni. "Effects of Alpha-Synuclein Targeted Antisense Oligonucleotides on Lewy Body-Like Pathology and Behavioral Disturbances Induced by Injections of Pre-Formed Fibrils in the Mouse Motor Cortex." Journal of Parkinson's Disease 11, no. 3 (August 2, 2021): 1091–115. http://dx.doi.org/10.3233/jpd-212566.

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Background: Alpha-synuclein (αsyn) characterizes neurodegenerative diseases known as synucleinopathies. The phosphorylated form (psyn) is the primary component of protein aggregates known as Lewy bodies (LBs), which are the hallmark of diseases such as Parkinson’s disease (PD). Synucleinopathies might spread in a prion-like fashion, leading to a progressive emergence of symptoms over time. αsyn pre-formed fibrils (PFFs) induce LB-like pathology in wild-type (WT) mice, but questions remain about their progressive spread and their associated effects on behavioral performance. Objective: To characterize the behavioral, cognitive, and pathological long-term effects of LB-like pathology induced after bilateral motor cortex PFF injection in WT mice and to assess the ability of mouse αsyn-targeted antisense oligonucleotides (ASOs) to ameliorate those effects. Methods: We induced LB-like pathology in the motor cortex and connected brain regions of male WT mice using PFFs. Three months post-PFF injection (mpi), we assessed behavioral and cognitive performance. We then delivered a targeted ASO via the ventricle and assessed behavioral and cognitive performance 5 weeks later, followed by pathological analysis. Results: At 3 and 6 mpi, PFF-injected mice showed mild, progressive behavioral deficits. The ASO reduced total αsyn and psyn protein levels, and LB-like pathology, but was also associated with some deleterious off-target effects not involving lowering of αsyn, such as a decline in body weight and impairments in motor function. Conclusions: These results increase understanding of the progressive nature of the PFF model and support the therapeutic potential of ASOs, though more investigation into effects of ASO-mediated reduction in αsyn on brain function is needed.

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Dissertations / Theses on the topic "PFFC"

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Willis, David Joe 1978. "A pFFT accelerated high order panel method." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/78436.

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Kantzon, David. "PFC-design for frequency converter." Thesis, Linköpings universitet, Fysik och elektroteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-124547.

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This thesis deals with power factor correction for three-phase systems. A boost-buck topology was described, modeled and then simulated in MATLAB/Simulink. The simulation results show that the system provides a power factor over 99% over the tested power output range. Moreover, the harmonic injection concept was introduced which reduces the total harmonic distortion to 8.72% at full output power. A prototype system was also built using an FPGA for the control system. The prototype did not provide the performance seen in simulation but showed that the method is valid and does provide a higher power factor when used.

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Bignold, Simon M. "Optimisation of the PFC functional." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/80984/.

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In this thesis we develop and analyse gradient-fl ow type algorithms for minimising the Phase Field Crystal (PFC) functional. The PFC model was introduced by Elder et al [EKHG02] as a simple method for crystal simulation over long time-scales. The PFC model has been used to simulate many physical phenomena including liquid-solid transitions, grain boundaries, dislocations and stacking faults and is an area of active physics and numerical analysis research. We consider three continuous gradient fl ows for the PFC functional, the L2-, H-1- and H2-gradient fl ows. The H-1-gradient flow, known as the PFC equation, is the typical flow used for the PFC model. The L2-gradient flow is known as the Swift-Hohenberg equation. The H2-gradient ow appears to be a novel feature of this thesis and will motivate our development of a line search algorithm. We analyse two methods of time discretisation for our gradient fl ows. Firstly, we develop a steepest descent algorithm based on the H2-gradient fl ow. We further develop a convex-concave splitting of the PFC functional, recently proposed by Elsey and Wirth [EW13], to discretise the L2- and H-1-gradient flows. We are able to prove energy stability of both our steepest descent algorithm and the convex-concave splitting scheme of [EW13]. We then use the Lojasiewicz gradient inequality (first developed in [ Loj62]) to prove that all three schemes converge to equilibrium. For numerical simulations we undertake spatial discretisation of our schemes using Fourier spectral methods. We consider a number of implementation issues for our fully discrete algorithms including a striking issue that occurs when the number of spatial grid points is low. We then perform several numerical tests which indicate that our new steepest descent algorithm performs well compared with the schemes of [EW13] and even compared with a Newton type scheme (the trust region method).

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Pippig, Michael. "PFFT - An Extension of FFTW to Massively Parallel Architectures." Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-87717.

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We present a MPI based software library for computing the fast Fourier transforms on massively parallel, distributed memory architectures. Similar to established transpose FFT algorithms, we propose a parallel FFT framework that is based on a combination of local FFTs, local data permutations and global data transpositions. This framework can be generalized to arbitrary multi-dimensional data and process meshes. All performance relevant building blocks can be implemented with the help of the FFTW software library. Therefore, our library offers great flexibility and portable performance. Likewise FFTW, we are able to compute FFTs of complex data, real data and even- or odd-symmetric real data. All the transforms can be performed completely in place. Furthermore, we propose an algorithm to calculate pruned FFTs more efficiently on distributed memory architectures. For example, we provide performance measurements of FFTs of size 512^3 and 1024^3 up to 262144 cores on a BlueGene/P architecture.

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Miller, Daniel [Verfasser]. "Optimierung einer eingangsgleichrichterlosen Leistungsfaktorkorrekturschaltung (PFC) / Daniel Miller." München : Verlag Dr. Hut, 2018. http://d-nb.info/1156510481/34.

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Schiff, Albrecht Johannes. "Optimised PFC circuits for efficient power conversion." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611141.

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Matejov, Michal. "Pasivní PFC filtry pro spínané napájecí zdroje." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217598.

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This work deals with theory of switched power sources. There is description of the ways for connection and their practice purposes. In the next parts there are defined requirements on input supply circuit for these sources, especially for the form of output current. There are mentioned the basic connecting methods of PFC circuits and these methods modify the output current to meet the requirements of specification ČSN EN 61000- 3- 2. In the next parts there are shown simulations of PFC circuits made by Pspice application. Further is the basic description of sources construction for the sources which were used for testing and measuring. The final part deals with evaluation of the measuring on the chosen computer’s source. It compares between the manufacturer’s solutions and PFC circuit made by ourselves.

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Livingstone, Phil. "Nicotinic modulation of dopaminergic signalling in the PFC." Thesis, University of Bath, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.528111.

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Sartori, Hamiltom Confortin. "Uma nova metodologia de projeto para otimização do volume do converosr boost PFC." Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/8466.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
This work investigates the influence of operation point (Δi @ fs) in the final volume of PFC boost converter. The boost inductor, EMI filter and thermal heatsink are the elements which main influences in the converter volume. These elements are strongly influenced by the chosen operation point, showing a direct relationship among them. With the increase of switch frequency and of the input current ripple occurs reduction of the boost inductor volume. On the other hand, it increases the switching losses in semiconductors, and influence on the EMI filter volume. It should be highlight that the optimum designs of individual devices or parameters of a system could not take the optimization of the overall system. In this form it is strongly recommended that the engineers and designers take into account the overall system, as well available technologies, standard and recommendation, and finally market commitments. The methodology presented realize the converter design in a integrate form, selecting the operation point that the converter finds the minimal total volume, starting from input variable output power, input and output voltage. The design takes into account different semiconductors technologies, different input filter topologies, different heart sinks profile, different magnetic cores technologies further of international standards that the converter must be adapt. Based on an integrate design of converter parameters is possible optimize the design finding the operation point for the minimal volume.
Esse trabalho investiga o impacto do ponto de operação (Δi @ fs) no volume final do conversor boost operando como pré regulador com correção do fator de potência (PFC). Os elementos de maior influência no volume do conversor são o indutor boost, o filtro de entrada e os dissipadores térmicos. O volume destes elementos é diretamente influenciado pelo ponto de operação, mostrando uma relação direta entre eles. Com o aumento da freqüência de comutação e da ondulação da corrente de entrada ocorre a diminuição do indutor boost, porém, aumentam as perdas nas comutações dos semicondutores e aumenta o volume do filtro de entrada. Com a diminuição da freqüência e da ondulação da corrente ocorre o inverso, sabendo disto, fica claro que projetar individualmente cada um destes três elementos pode resultar em um bom projeto individual, contudo penaliza os outros parâmetros. Assim, a metodologia apresentada realiza o projeto do conversor de forma integrada, escolhendo o ponto de operação em que o conversor encontre o volume final mínimo, partindo de algumas variáveis de entrada, como potência de saída e tensões de entrada e saída. O projeto leva em consideração diferentes tecnologias de semicondutores, topologias de filtros de entrada, perfis de dissipadores térmicos, tecnologias de núcleos magnéticos além das normas internacionais a que o conversor deve se adequar. Baseado no projeto integrado dos parâmetros do conversor é possível otimizar o projeto encontrando o ponto de operação para o volume total mínimo do conversor.

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Zhou, Bo. "CCM Totem Pole Bridgeless PFC with Ultra Fast IGBT." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/51120.

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The totem pole PFC suffers from the Mosfet body diode reverse recovery issue which limits this topology adopted in the CCM high power condition. As the ultra-fast IGBT which is capable of providing 100 kHz switching frequency is available in the market, it is possible to apply the totem pole PFC in CCM high power condition. The thesis provides a method by implementing the ultra-fast IGBT and SiC diode to replace the MOSFET in this topology. To verify the method, a universal CCM totem pole PFC is designed and tested. The design adopts the ADP1048 programmable digital PFC controller by adding external logic gate for totem-pole PFC. ADP1048 greatly simplifies the design process and satisfies the design requirements. The experiment results verify that the totem-pole PFC can be applied into CCM high power condition by using the method. The DC output voltage is well regulated. The power factor is higher than 0.98 when the load is above 400W. The measured efficiency can achieve up to 96.8% at low line and 98.2% at high line condition with switching frequency 80 kHz.
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Books on the topic "PFFC"

1

Dantas, Nara Soares. Medicamentos excepcionais: MPF, PFDC. Brasília, DF: ESMPU, 2006.

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Richard, Brooks. PFC programmers' reference manual. Greenwich, CT: Manning, 1998.

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Le secret de la conjugaison ou La conjugaison, pfff--, trop facile! Crépieux-la-Pape: Happyparents, 2009.

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Flynn, Sean J. An engineer's war: The legacy of PFC Alfred Hutchison. Sioux Falls, SD: Pine Hill Press, 2004.

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Farrington, Arthur C. The leatherneck boys: A PFC at the battle for Guadalcanal. Manhattan, Kan., USA: Sunflower University Press, 1995.

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McGrath, Robert. Plasma Facing Components Generic Facilities Review Panel (PFC-GFRP): Final report. Albuquerque, New Mexico: Sandia National Laboratories, 1993.

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Cette mystérieuse section coloniale: Le PFC et les colonies, 1920-1962. Paris: Messidor, 1986.

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Hugh, Roy. Roy Hugh: The boy from Bisbee that went to war PFC to Brigadier General. Bloomington, IN: AuthorHouse, 2008.

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Cheglov, Vyacheslav. Trade business. Economics and management of retail chains. ru: INFRA-M Academic Publishing LLC., 2020. http://dx.doi.org/10.12737/1056723.

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The textbook summarizes the author's twenty-year experience in such large network trading companies as Klass, PFC BIN, and X5 Retail Group. It is written in accordance with the curriculum and educational and methodological complex for the discipline "Economic activity of retail chains", which is part of the cycle of academic disciplines of the master's program "Organization and technology of trade business", direction "trade business". Covers a wide range of issues related to the theory and practice of network retail enterprises. Introduces readers to the forms of network business organization in retail, modern formats of retail trade, the organization of the trading process on the network principle and its features, current regulatory legal acts regulating the activities of network retail companies. Meets the requirements of Federal state educational standards of higher education of the latest generation. For students of economic and trade universities, students of universities and training centers of retail trading companies, managers engaged in retail.

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Feldman, Roddy N. Monty's war: The combat history of PFC La Mont A. Seifert : United States Army serial # 37 562 178, 1943-1946. Fairfield, Calif: Nostromo Pub., 2009.

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Book chapters on the topic "PFFC"

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Braun-Falco, Markus, Henry J. Mankin, Sharon L. Wenger, Markus Braun-Falco, Stephan DiSean Kendall, Gerard C. Blobe, Christoph K. Weber, et al. "PFIC Type 1." In Encyclopedia of Molecular Mechanisms of Disease, 1633. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-29676-8_7852.

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Braun-Falco, Markus, Henry J. Mankin, Sharon L. Wenger, Markus Braun-Falco, Stephan DiSean Kendall, Gerard C. Blobe, Christoph K. Weber, et al. "PFIC Type 2." In Encyclopedia of Molecular Mechanisms of Disease, 1633. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-29676-8_7853.

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Braun-Falco, Markus, Henry J. Mankin, Sharon L. Wenger, Markus Braun-Falco, Stephan DiSean Kendall, Gerard C. Blobe, Christoph K. Weber, et al. "PFIC Type 3." In Encyclopedia of Molecular Mechanisms of Disease, 1633. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-29676-8_7854.

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Winter, Patrick M., Gregory M. Lanza, Samuel A. Wickline, Marc Madou, Chunlei Wang, Parag B. Deotare, Marko Loncar, et al. "PFC Nanoparticles." In Encyclopedia of Nanotechnology, 2051. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-90-481-9751-4_100640.

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Kenanidis, Eustathios, Eleftherios Tsiridis, Libor Nečas, Marek Rovňák, Martin Buttaro, John A. Scolaro, Ran Schwarzkopf, Joseph M. Statz, Cameron K. Ledford, and Robert T. Trousdale. "Periprosthetic Femoral Fractures (PFFs)." In The Adult Hip - Master Case Series and Techniques, 791–816. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-64177-5_39.

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Dellefield, R. J. "Economics of PFBC technology." In Pressurized Fluidized Bed Combustion, 515–42. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0617-7_14.

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Springer, Michael. "Pfft – vertrauen Sie mir." In Unendliche Neugier, 78–80. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-54891-2_21.

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Wang, Hua, and Zhao-yong You. "PFFM and Quasi-Morishima matrices." In Lecture Notes in Computer Science, 392–95. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/bfb0030857.

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Mudd, M. J. "General configuration of PFBC plants." In Pressurized Fluidized Bed Combustion, 121–34. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0617-7_4.

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Schlienz, Ulrich. "PFC Power-Factor-Corrector." In Schaltnetzteile und ihre Peripherie, 135–52. Wiesbaden: Springer Fachmedien Wiesbaden, 2020. http://dx.doi.org/10.1007/978-3-658-29490-8_13.

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Conference papers on the topic "PFFC"

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Al-Ansary, Hany, Shaker Alaqel, Eldwin Djajadiwinata, and Abdullah Mohammed. "Optical Analysis of a New Point Focus Fresnel Concentrator." In ASME 2015 9th International Conference on Energy Sustainability collocated with the ASME 2015 Power Conference, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/es2015-49340.

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This study describes preliminary optical analysis performed regarding a new collector called the Point Focus Fresnel Concentrator (PFFC). This collector combines the concepts of the linear Fresnel collector and central receiver systems to form a new concept of a focal point Fresnel concentrator with a dual-axis sun tracking system. It concentrates direct solar radiation using a number of flat mirrors positioned over a rotating frame. The frame tracks the sun in the azimuth direction, while each row of mirrors tracks the sun in the elevation direction, thereby allowing sunlight to be concentrated on the same point above the collector throughout the day. PFFC is considered suitable for a number of applications, such as power generation by concentrating photovoltaics (CPV) and Stirling engines, and process heat applications. In this study, the first attempt to characterize the optical performance of the collector is made. A prototype of the collector has already been built on the campus of King Saud University. It has a total footprint of 9 m2, and includes 900 mirrors, each of which is 7 cm × 7 cm. The receiver has a diameter of 10 cm. Optical performance is studied by ray tracing methods to obtain flux maps and intercept factors of the receiver. Results show that the average concentration ratio is in the order of 220 to 300 suns when mirrors with a 6-mrad optical error are used. For the same mirrors, the highest attainable average intercept factor (0.674) occurs in the winter due to the low particle loading in the atmosphere. When the optical error is reduced to 2 mrad, the average concentration ratio increases to 290 to 400 suns, and the average intercept factor increases to 0.892. In any case, if the current design of PFFC is to be used in conjunction with CPV, a secondary concentrator would be needed to achieve required concentration ratios in the order of 500 suns.

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Nilsson, Jan C., Jim Anderson, and Per Thörnblad. "The GT140 P-Machine is Extensively Tested for Commercial Application." In ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-121.

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In order to attain large utility PFBC plant size a fourfold scale-up of the existing 80–100 MW design was undertaken. This has resulted in the design and manufacture of a new gas turbine, the GT140P, which is an integral part of the 400 MWe PFBC plant. The first GT140P has been subjected to rigorous testing prior to installation in Japan, further verifying the PFBC concept.

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Newby, R. A., W. F. Domeracki, A. W. McGuigan, and R. L. Bannister. "Integration of Combustion Turbine Systems Into Pressurized Fluidized Bed Combustion Combined Cycles." In ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-333.

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Currently, pressurized fluidized bed combustion (PFBC) combined cycle power plants apply multiple stages of cyclones to clean the combustion products prior to turbine expansion, and rugged, inefficient expanders are required for this dirty-gas duty. The turbine inlet temperature is limited to the fluid bed combustor temperature, about 843°C (1550°F), so the plant thermal efficiency is relatively low. The development of hot gas filtration and coal-gas topping for PFBC combined cycles is the next step in the evolution of PFBC, and will result in the use of modern, high-efficiency combustion turbines in PFBC applications as well as plant thermal efficiencies up to 47% (HHV). Westinghouse is developing integrated combustion turbine systems that interface with PFBC plants and incorporate the functions of hot gas filtration, alkali vapor removal, topping combustion, hot gas piping and control, and turbine compression and expansion. This paper reports on the engineering considerations made by Westinghouse for these integrated combustion turbine systems and summarizes the current development activities and status.

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Wang, Alan L. T., and John F. Stubington. "Hydrodynamic Performance of a Novel Design of Pressurized Fluidized Bed Combustor." In 17th International Conference on Fluidized Bed Combustion. ASMEDC, 2003. http://dx.doi.org/10.1115/fbc2003-057.

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A bench-scale fluidized bed combustor with a novel fluidizing gas injection manifold was successfully built for characterization of Australian black coals under pressurized fluidized bed combustion (PFBC) conditions. The bed of silica sand (mean size 1.3 mm and density 2700 kg/m3) was 40 mm ID with a static height of 75 mm. This facility was designed to operate at 1.6 MPa, 850°C and a fluidizing velocity of 0.9 m/s, identical to those used industrially, in order to match as closely as possible the local hydrodynamic environment around each coal particle in an industrial PFBC. To verify satisfactory hydrodynamic performance with the novel gas injection manifold, the fluidization was directly investigated by measuring differential pressure fluctuations under both ambient and PFBC conditions. In addition, a Perspex cold model was built to simulate at ambient conditions the hydrodynamics of the hot bed in this PFBC facility. The cold model was constructed to a geometric scale of 1.431:1, determined by Glicksman’s scaling law. Under PFBC conditions of 1.6 MPa, 850°C and 0.9 m/s, the bed in UNSW’s PFBC facility operated in a stable bubbling regime and the solids were very well mixed. The bubbles in this PFBC were effectively cloudless and no gas backmixing or slugging occurred; so the gas flow in this bed could be modeled by assuming two phases (bubble and particulate) with plug flow through each phase. The results from the cold model showed that the ratio of Umf for the simulated bed to Umf for the hot PFBC bed matched the conditions proposed by Glicksman’s scaling laws. The bubbles rose along the bed with axial and lateral movements (moving both towards and from the wall), and erupted from the bed surface evenly and randomly at different locations. Two patterns of particle movement were observed in the cold model bed: a circular pattern near the top section, and a rising and falling pattern dominating the particle movement in the lower section created by the rising bubbles.

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Park, Youngwoo, Seung-Ho Lim, Chul Lee, and Kyu Ho Park. "PFFS." In the 2008 ACM symposium. New York, New York, USA: ACM Press, 2008. http://dx.doi.org/10.1145/1363686.1364038.

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Jansson, Sven A., Dirk Veenhuizen, Krishna K. Pillai, and Jan Björklund. "The Coal-Fired PFBC Machine: Operating Experience and Further Development." In ASME 1996 Turbo Asia Conference. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-ta-011.

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The key components of Pressurized Fluidized Bed Combined Cycle (PFBC) plants are the specially designed gas turbine, which we refer to as the PFBC machine, and the pressurized fluidized bed boiler used to generate and superheat steam for expansion in a steam turbine, in ABB’s P200 and P800 modules, ABB Stal’s 17 MWe GT35P and 70 MWe GT140P machines, respectively, are used. Particulate cleanup before expansion in the turbine sections is with cyclones. So far, over 70,000 hours of operation has been accumulated on P200 modules in the world’s first PFBC plants, demonstrating that PFBC meets the expectations. The GT35P machines have been found to perform as expected, although some teething problems have also been experienced. The next P200 plant will be built in Germany for operation on brown coal. The first GT140P machine has been manufactured. After shop testing in Finspong, it will be shipped to Japan for installation in the first P800 plant, which is under construction. Future development of the PFBC machines are foreseen to include raising the turbine inlet temperature through combustion of a topping fuel in order to reach thermal efficiencies which ultimately may be in the range of 50 to 53% (LHV).

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Knudsen, Knud, Jonas Larsson, Ulf Nilsson, and Per Thörnblad. "Workshop Testing of GT140P: Part 1 — Test Program and Test Arrangement." In ASME 1999 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/99-gt-242.

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Based on the experience from operation of 75 MW PFBC power plants in Sweden, Spain and USA, development of a gas turbine for a larger PFBC plant started in 1990. Before delivery to its user in Japan the first machine underwent extensive testing. A special test rig was built in one of ABB STAL’s workshops in Finspong Sweden. In the absence of the regular coal-fired PFBC combustor a silo-type gas turbine combustor was installed to supply power. Permanent and temporary instrumentation, together more than 1200 gauges, were installed and data was displayed for on-line monitoring and recorded for analysis. This paper describes the design of GT140P, the test program and the test arrangements.

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McClung, James D. "Corrosion/Erosion Potential of Selected Turbine Materials in a PFBC Environment." In 1985 Joint Power Generation Conference: GT Papers. American Society of Mechanical Engineers, 1985. http://dx.doi.org/10.1115/85-jpgc-gt-12.

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A pressurized fluidized-bed combustion combined-cycle (PFBC/CC) concept represents an attractive system for generating electric power at high efficiencies while meeting environmental requirements. An integral part of the technology required for commercialization is the long-term, trouble-free operation of the gas turbine in the high-temperature effluent from the PFBC. This environment has significant potential for corrosion, erosion and deposition in the gas turbine. The occurrence of any one or combination of these three processes may result in the loss of turbine efficiency and/or reduced power output. This paper summarizes and compares recent results of experimental tests assessing the corrosion and erosion potential of selected gas turbine materials. Based on these and earlier results in simulated and actual PFBC environments, the corrosion and erosion potential of gas turbine materials is assessed.

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Won, Hui-Jun, Gye-Nam Kim, Wang-Kyu Choi, Chong-Hun Jung, and Won-Zin Oh. "Metal Surface Decontamination by the PFC Solution." In 14th International Conference on Nuclear Engineering. ASMEDC, 2006. http://dx.doi.org/10.1115/icone14-89210.

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PFC (perfluorocarbon) spray decontamination equipment was fabricated and its decontamination behavior was investigated. Europium oxide powder was mixed with the isotope solution which contains Co-60 and Cs-137. The different shape of metal specimens artificially contaminated with europium oxide powder was used as the surrogate contaminants. Before and after the application of the PFC spray decontamination method, the radioactivity of the metal specimens was measured by MCA. The decontamination factors were in the range from 9.6 to 62.4. The spent PFC solution was recycled by distillation. Before and after distillation, the turbidity of PFC solution was also measured. From the test results, it was found that more than 98% of the PFC solution could be recycled by a distillation.

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Wright, I. G., and J. Stringer. "Erosion and Corrosion Considerations for PFBC Gas Turbine Expanders." In ASME 1986 International Gas Turbine Conference and Exhibit. American Society of Mechanical Engineers, 1986. http://dx.doi.org/10.1115/86-gt-217.

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Considerable interest has been developed over the past few years in the application of gas turbines to expand the hot, dirty flue gases from pressurized fluidized-bed combustors (PFBCs) burning coal. Although no full-size gas turbine has yet operated on a PFBC, firm commitments have been made to build commercial PFBC-GT power plants. In addition, there are a number of projects at various stages of development aimed at operating gas turbines on dirty fuels ranging from the expansion of flue gas from the combustion of pulverized coal, to the direct firing of coal-water mixtures. Common concerns of all these applications include erosion and corrosion of the gas turbine hot gas path components. This paper attempts to provide an overview of results of research and testing so far reported in these areas, and to make an assessment of the engineering trade-offs required for the successful operation of PFBC gas turbine expanders.

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Reports on the topic "PFFC"

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White, J. S., and D. L. Bonk. Advanced PFBC transient analysis. Office of Scientific and Technical Information (OSTI), May 1997. http://dx.doi.org/10.2172/481947.

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Bland, A. E. Market assessment of PFBC ash use. Office of Scientific and Technical Information (OSTI), January 1998. http://dx.doi.org/10.2172/293395.

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National Energy Technology Laboratory. Tidd PFBC Demonstration Project, A DOE Assessment. Office of Scientific and Technical Information (OSTI), August 2001. http://dx.doi.org/10.2172/786183.

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Archie Robertson. Second Generation PFBC Systems R&D. Office of Scientific and Technical Information (OSTI), August 2000. http://dx.doi.org/10.2172/882012.

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Archie Robertson. Second Generation PFBC Systems R&D. Office of Scientific and Technical Information (OSTI), May 2000. http://dx.doi.org/10.2172/882013.

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Archie Robertson. Second Generation PFBC Systems R&D. Office of Scientific and Technical Information (OSTI), March 2000. http://dx.doi.org/10.2172/882016.

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Archie Robertson. Second-Generation PFBC Systems R&D. Office of Scientific and Technical Information (OSTI), January 2000. http://dx.doi.org/10.2172/882017.

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Archie Robertson. Second-Generation PFBC Systems R&D. Office of Scientific and Technical Information (OSTI), April 2000. http://dx.doi.org/10.2172/882014.

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Dolan, Daniel H. Portable File Format (PFF) specifications. Office of Scientific and Technical Information (OSTI), February 2015. http://dx.doi.org/10.2172/1169933.

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Lee, S. H. D., and W. M. Swift. Measurement of alkali vapors in PFBC exhaust. Final report. Office of Scientific and Technical Information (OSTI), January 1994. http://dx.doi.org/10.2172/10148110.

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