Academic literature on the topic 'Reactor block'
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Journal articles on the topic "Reactor block"
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Kalyuzhnyi, Sergey, and Vyacheslav Fedorovich. "Integrated mathematical model of UASB reactor for competition between sulphate reduction and methanogenesis." Water Science and Technology 36, no. 6-7 (September 1, 1997): 201–8. http://dx.doi.org/10.2166/wst.1997.0592.
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The existing mathematical models of anaerobic treatment processes were mainly developed for ideally mixed reactors with no concentration gradients on substrates, intermediates, products and bacteria inside the reactor. But for conventional UASB reactors with low upward velocity, the distribution of these components along the reactor height is very far from uniform. This paper presents an integrated mathematical model of the functioning of UASB reactor taking into account this non-uniformity as well as multiple-reaction stoichiometry and kinetics. In general, our integrated model includes the following blocks: a) kinetic block, including the growth and metabolism of acidogenic, acetogenic, methanogenic and sulphate-reducing bacteria; b) physico-chemical block, for the calculation of pH in each compartment of the liquid phase; c) hydrodynamic block, describing liquid flow as well as the transport and distribution of the components along the reactor height; d) transfer block, describing a mass transfer of gaseous components from the liquid to gas phase. This model was calibrated to some experimental studies of the functioning of UASB reactors made by in 1994. Hypothetical computer simulations are presented to illustrate the influence of different factors (recycle number, hydraulic retention time, quality of seed sludge, SO42−:COD ratio etc.) on the operation performance of UASB reactor.
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Nikolaev, A. "FRIGATE CODE TO THE COMPLEX SCENARIZED CORE AND SHIELDING CALCULATIONS IN GROUPWISED APPROXIMATION: BACKGROUND OF CREATION, ORGANIZATION STRUCTURE, FUNCTIONALITY." PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY. SERIES: NUCLEAR AND REACTOR CONSTANTS 2020, no. 1 (March 26, 2020): 37–49. http://dx.doi.org/10.55176/2414-1038-2020-1-37-49.
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The short information about destination and abilities of program FRIGATE, structure description and program characteristics are presented. The FRIGATE program implements the methodology developed by the authors of a free programmable organization of complex interconnected multicomponent calculations to justify the design characteristics of reactors and protect reactor installations in a group approximation. The FRIGATE program within the framework of a single executable file allows the user to organize arbitrary chains of standard calculations to solve the main tasks of the design support of reactor installation design. The structure of the FRIGATE program is organized according to the principle of a set of interacting process units. Each program block performs a separate logically closed task. The program includes the following blocks: a geometric block, an SN block (based on the PMSNSYS-II program), a block group block preparation block, point kinetics parameter calculation block, a perturbation theory calculator of reactivity effects, a unit for working with ionizing radiation field functionals, isotope kinetics calculation unit, as well as other computational and / or service subroutine blocks. The program has no restrictions on the number of nuclides, the number of physical zones, cells, the number of nuclides in the zone, and the like. Parallelization of lengthy calculations in the current version of the program is organized using the OpenMP 3.0 standard. A set of software documents has been released for the program.
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TERAI, Yuzo. "Block Metal-Fuel Fast Reactor." Proceedings of the National Symposium on Power and Energy Systems 2019.24 (2019): B113. http://dx.doi.org/10.1299/jsmepes.2019.24.b113.
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Branchu, Joël, and Charles Gigarel. "Superphénix 1 Reactor Block Fabrication." Nuclear Technology 68, no. 2 (February 1985): 135–45. http://dx.doi.org/10.13182/nt85-a33549.
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Morozenko, Andrey, and Alexey Shashkov. "Labor costs management in the large-block construction of NPP." E3S Web of Conferences 263 (2021): 02040. http://dx.doi.org/10.1051/e3sconf/202126302040.
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The article continues the research of the features of the use of prefabricated cast-in-place structures in the construction of nuclear power plants (NPP), the organizational and economic feasibility of the use of prefabricated cast-in-place structures in the implementation of new projects for the construction of nuclear power plants. The estimation of labor costs and resource costs of installation of large-block structures for the reactor building of the NPP was made. The dependence of labor costs for the installation of reinforced blocks, depending on the share of using reinforced blocks during the construction of the reactor building of a nuclear power plant, was obtained. The dependence of the overall labor costs for the industrial production and installation of reinforced blocks, depending on the share of using reinforced blocks during the construction of the reactor building of a nuclear power plant, was obtained. Graphical representations of dependencies are illustrated. The main daily resource consumption for the installation of reinforced blocks during large-block construction has been analytically calculated. The data on the required shares of labor costs at industrial enterprises and at the construction site in percentage terms were obtained. The conclusion is made about the rational use of large-block construction in the implementation of NPP construction projects.
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Shamanin, Igor, Sergey Bedenko, Yuriy Chertkov, and Ildar Gubaydulin. "Gas-Cooled Thorium Reactor with Fuel Block of the Unified Design." Advances in Materials Science and Engineering 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/392721.
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Scientific researches of new technological platform realization carried out in Russia are based on ideas of nuclear fuel breeding in closed fuel cycle and physical principles of fast neutron reactors. Innovative projects of low-power reactor systems correspond to the new technological platform. High-temperature gas-cooled thorium reactors with good transportability properties, small installation time, and operation without overloading for a long time are considered perspective. Such small modular reactor systems at good commercial, competitive level are capable of creating the basis of the regional power industry of the Russian Federation. The analysis of information about application of thorium as fuel in reactor systems and its perspective use is presented in the work. The results of the first stage of neutron-physical researches of a 3D model of the high-temperature gas-cooled thorium reactor based on the fuel block of the unified design are given. The calculation 3D model for the program code of MCU-5 series was developed. According to the comparison results of neutron-physical characteristics, several optimum reactor core compositions were chosen. The results of calculations of the reactivity margins, neutron flux distribution, and power density in the reactor core for the chosen core compositions are presented in the work.
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Trinh, Dinh Hai, Van Tai Vo, Van Diep Le, and Nhi Dien Nguyen. "Design and Construction of a Preamplifier for Research Reactor Control System Using Russia’s Neutron Detectors." Nuclear Science and Technology 6, no. 3 (September 30, 2016): 8–15. http://dx.doi.org/10.53747/jnst.v6i3.159.
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This paper presents the design and construction of a preamplifier device for Research Reactor Control System, using Russia’s Neutron Detectors of ionization and fission chambers. In this work, the preamplifier device which consists of a wide range Current to Frequency Converter block used with a compensation ionization chamber type KNK-3 to measure the thermal neutron flux in the range of 1x106 ¸ 1x1011 n/cm2.s, a Pulse Preamplifier block used with a fission chamber type KNK-15 to measure the thermal neutron flux in the range of 1x100 ¸ 1x106 n/cm2.s, and a Power Supply block, was designed and tested in different conditions in the laboratory and at Dalat Nuclear Research Reactor (DNRR). Obtained results show that, the above blocks have almost design specifications as equivalent or better in comparison with the same function blocks of the DNRR’s Control System which were designed by the former Soviet Union. They also meet the utilization requirements as well as the experimental and training purposes.
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Rizki, M., Oktavian, Volkan Seker, Brendan Kochunas, and Yunlin Xu. "Accurate Nodal Diffusion Modelling on the High Temperature Test Reactor (HTTR)." Journal of Physics: Conference Series 2048, no. 1 (October 1, 2021): 012023. http://dx.doi.org/10.1088/1742-6596/2048/1/012023.
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Abstract The High Temperature Test Reactor is a 30-MWth helium-cooled, graphite-moderated, prismatic-type gas reactor developed by the Japan Atomic Energy Agency (JAEA). The hexagonal shape of fuel blocks in the HTTR core combined with complex inner structures containing TRISO particles results in the double-heterogeneity effect that increases the simulation challenge of the reactor. This research has a goal to accurately model the HTTR fuel blocks employing the standard two-step procedure of a reactor analysis: employ a lattice physics calculation to generate homogeneous cross sections and use them in a nodal diffusion calculation. The implementation of the diffusion approximation results in a faster calculation with acceptable accuracy compared to the high-resolution lattice calculation. An advanced method called Triangular Polynomial Expansion Nodal (TriPEN) method was used in this work for the nodal diffusion calculation to accurately model the flux discontinuity effect between blocks by generating discontinuity factors in each surface and corner point. To do this, the heterogeneous solutions obtained from the lattice physics calculation, which is done by Serpent Monte Carlo in this case, are utilized by TriPEN to generate the discontinuity factors. Due to its capability to simulate any reactor geometry with a high-resolution, the results generated from Serpent calculation were also used as the reference cases for this work. In this work, the TriPEN method is implemented in the PARCS core neutronic module inside AGREE, a U.S. N.R.C. Multiphysics code system for the High Temperature Reactor (HTR). Test cases conducted for this method involved the original design of the HTTR. The 4-hex model built consisted of the central control-rod block of HTTR together with 6 of the half-fuel-blocks surround it. The differences in material composition in each assembly block in HTTR resulted in flux discontinuity effects on the assembly block interfaces. To correct this discrepancy, discontinuity factors were applied in order to make the homogenous solutions from the nodal calculation agree with the heterogeneous solutions from the lattice physics calculation. Applying this procedure to the HTTR nodal models, TriPEN is able to produce exact results in the eigenvalue compared to Serpent calculation, the rod worth calculated perfectly matched the reference, and the flux and power distribution only has negligible discrepancies.
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TERAI, Yuzo. "Piled Block Metal-Fuel Fast Breeder Reactor." Proceedings of the National Symposium on Power and Energy Systems 2018.23 (2018): A235. http://dx.doi.org/10.1299/jsmepes.2018.23.a235.
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Peltan, Tomas, Eva Vilimova, Tomas Czakoj, Zdenek Matej, Filip Mravec, Frantisek Cvachovec, Jan Simon, Vlastimil Juricek, and Michal Kostal. "Specially developed LR-0 reactor graphite environment for gen IV reactor support and cross-section measurement." EPJ Web of Conferences 288 (2023): 04024. http://dx.doi.org/10.1051/epjconf/202328804024.
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This paper is focused on the development of the experimental environment connected to reactor graphite. Regarding its very good neutronic and mechanical properties, graphite will be very important in some new reactor designs, such as high-temperature or molten salt SMR reactors. These new reactor concepts require a new experimental environment as support for further research. In the laboratories of the Research Centre Řež and at the LR-0 reactor, the new experimentally validated graphite environment was created. This large graphite insertion is the largest graphite mono-block, which is possible to assemble at the LR-0 reactor. Sets of experiments for measuring reaction rates of different activation detectors for neutron field mapping were performed. This approach was used for thermal and epithermal region descriptions. For the fast neutron spectrum evaluation, the stilbene scintillation detector was used. All parameters, such as criticality height of moderator level, neutron spectrum, and other parameters for all experiments, were performed using Monte Carlo neutronic codes Serpent and MCNP. The obtained results were finally compared to the measurement of neutron leakage spectra from the graphite cube and graphite cylinder. These specially developed graphite-shaped neutron fields, reactor insertions, and external cube and cylinder with Cf neutron source can be used in the future for validation of not only materials used in SMR reactors but for arbitrary cross-section verification.
Dissertations / Theses on the topic "Reactor block"
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Novikov, Yehor. "1-Bromo-1-lithioethene as a building block for organic synthesis." [Kent, Ohio] : Kent State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1135388929.
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Thesis (Ph.D.)--Kent State University, 2005.Title from PDF t.p. (viewed July 25, 2006). Advisor: Paul Sampson. Keywords: organolithiums, Felkin-Anh diastereoselectivity, low temperatures, cryogenic reactor, carbohydrates, building blocks. Includes bibliographical references (p. 186-197).
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Muga, Julius N’gon’ga. "Design and implementation of IEC 61499 standard-based nonlinear controllers using functional block programming in distributed control platform." Thesis, Cape Peninsula University of Technology, 2015. http://hdl.handle.net/20.500.11838/2381.
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Thesis (DTech (Electrical Engineering))--Cape Peninsula University of Technology, 2016.Majority of the industrial systems encountered are significantly non-linear in nature, so if they are synthesised and designed by linear methods, then some of salient features characterising of their performance may not be captured. Therefore designing a control system that captures the nonlinearities is important. This research focuses on the control design strategies for the Continuous Stirred Tank Reactor (CSTR) process. To control such a process a careful design strategy is required because of the nonlinearities, loop interaction and the potentially unstable dynamics characterizing the system. In these systems, linear control methods alone may not perform satisfactorily. Three different control design strategies (Dynamic decoupling, Decentralized and Input-output feedback linearization controller) are proposed and implemented .in the Matlab/Simulink platform and the developed strategies are then deployed to the design of distributed automation control system configuration using the IEC 61499 standard based functional block programming language. Twin CAT 3.1 system real-time and Matlab/Simulink (www.mathworks.com) environment are used to test the effectiveness of the models The simulation results from the investigation done between Simulink and TwinCAT 3 software (Beckhoff Automation) platforms in the case of the model transformation and closed loop simulation of the process for the considered cases have shown the suitability and the potentials of merging the Matlab/Simulink control function blocks into the TwinCAT 3.1 function blocks in real-time. The merits derived from such integration imply that the existing software and software components can be re-used. This is in line with one of the IEC 6144 standard requirements such as portability and interoperability. Similarly, the simplification of programming applications is greatly achieved. The investigation has also shown that the integration the of Matlab/Simulink models running in the TwinCAT 3.1 PLC do not need any modification, hence confirming that the TwinCAT 3.1 development platform can be used for the design and implementation of controllers from different platforms. Also, based on the steps required for model transformation the between the Matlab/Simulink to the TwinCAT 3 functional blocks, the algorithms of the control design methodologies developed, simulation results are used to verify the suitability of the controls to find whether the effective set-point tracking control and disturbance effect minimisation for the output variables can be achieved in real-time using the transformed Simulink blocks to the TwinCAT 3 functional blocks, then downloaded to the Beckhoff CX5020 PLC for real-time execution. Good set-point tracking control is achieved for the MIMO closed loop nonlinear CSTR process for the considered cases of the developed control methodologies. Similarly, the effects of disturbances are investigated. TwinCAT functional modules achieved good set-point tracking with these disturbances minimization under all the cases considered.
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Северин, Валерій Петрович. "Моделі і методи оптимізації показників якості систем автоматичного управління енергоблоку атомної електростанції." Thesis, СПДФО Ізрайлев Є. М, 2007. http://repository.kpi.kharkov.ua/handle/KhPI-Press/32677.
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Дисертація на здобуття вченого ступеня доктора технічних наук за спеціальністю 05.13.07 – Автоматизація технологічних процесів. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2007.
Дисертація присвячена розробці перспективної концепції синтезу систем автоматичного управління енергоблоку атомної електростанції на основі математичних моделей і чисельних методів векторної оптимізації показників якості. Розроблені методи обчислення прямих показників якості й покращених інтегральних квадратичних оцінок, що мають високу точність і швидкодію. Обґрунтований покроковий принцип переходу до області стійкості системи, запропоновані векторні цільові функції, що включають умови стійкості і враховують пріоритети показників якості. Розроблені надійні методи оптимізації векторних цільових функцій. Отримані математичні моделі в просторі станів для систем автоматичного управління ядерним реактором, парогенератором та паровою турбіною. Виконана оптимізація показників якості систем управління енергоблоку, яка дозволила оцінити ефективність різних регуляторів.Thesis for a doctor’s degree in speciality 05.13.07 – automation of technological processes. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2007. The thesis is devoted to the development of a perspective concept of atomic station power block automatic control systems synthesis on the basis of mathematical models and numeric methods of vector optimization of systems quality indexes. The methods for calculation of direct quality indexes and improved integral quadratic estimates have been created. The step-by-step principle of transition to the domain of system stability has been based. There have also been suggested vector goal functions including stability conditions and taking into consideration quality indexes priorities. The reliable optimization methods of vector goal functions have been suggested. Mathematical models in the state space for automatic control systems of nuclear reactor, steam generator and steam turbine have been worked out. The quality indexes optimization of power block control systems has been carried out, which allowed to estimate various regulator types efficiency.
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Северин, Валерий Петрович. "Модели и методы оптимизации показателей качества систем автоматического управления энергоблока атомной электростанции." Thesis, СПДФЛ Израйлев Е. М, 2007. http://repository.kpi.kharkov.ua/handle/KhPI-Press/33459.
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Диссертация на соискание ученой степени доктора технических наук по специальности 05.13.07 – автоматизация технологических процессов. – Национальный технический университет "Харьковский политехнический институт", Харьков, 2007. Диссертация посвящена разработке перспективной концепции синтеза систем автоматического управления энергоблока атомной электростанции на основе математических моделей и численных методов векторной оптимизации показателей качества. Разработаны методы вычисления прямых показателей качества и улучшенных интегральных квадратичных оценок, имеющих высокую точность и быстродействие. Обоснован пошаговый принцип перехода в область устойчивости системы, предложены векторные целевые функции, включающие условия устойчивости и учитывающие приоритеты показателей качества. Разработаны надежные методы оптимизации векторных целевых функций. Получены математические модели в пространстве состояний для систем автоматического управления ядерным реактором, парогенератором и паровой турбиной. Проведена оптимизация показателей качества систем управления энергоблока, позволившая оценить эффективность различных регуляторов.Thesis for a doctor’s degree in speciality 05.13.07 – automation of technological processes. – National Technical University "Kharkov Polytechnic Institute", Kharkov, 2007. The thesis is devoted to the development of a perspective concept of atomic station power block automatic control systems synthesis on the basis of mathematical models and numeric methods of vector optimization of systems quality indexes. The methods for calculation of direct quality indexes and improved integral quadratic estimates have been created. The step-by-step principle of transition to the domain of system stability has been based. There have also been suggested vector goal functions including stability conditions and taking into consideration quality indexes priorities. The reliable optimization methods of vector goal functions have been suggested. Mathematical models in the state space for automatic control systems of nuclear reactor, steam generator and steam turbine have been worked out. The quality indexes optimization of power block control systems has been carried out, which allowed to estimate various regulator types efficiency.
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Tricàs, Rosell Núria. "Plasma modification on carbon black surface: From reactor design to final applications." Doctoral thesis, Universitat Ramon Llull, 2007. http://hdl.handle.net/10803/9288.
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El present treball es basa en l'estudi de la modificació de la superfície del negre de carboni (NC) per mitjà de tècniques de plasma. Tot i que aquest tipus de tractament s'utilitza de manera comú sobre superfícies planes, tanmateix encara existeixen problemes a l'hora de treballar en materials en pols degut a la dificultat que suposa la seva manipulació. En aquest treball s'ha modificat NC tant per tècniques de plasma a baixa pressió com per mitjà de tècniques de plasma atmosfèric. Per tal d'assolir aquest objectiu s'han posat a punt tres reactors de plasma capaços de modificar aquest tipus de material; dos reactors treballen a baixa pressió mentre que el tercer es tracta d'un equip a pressió atmosfèrica.Els sistemes de plasma a baixa pressió utilitzats han estat un reactor down-stream i un reactor de llit fluiditzat. Ambdós sistemes utilitzen un generador de radio freqüències a 13,56MHz per tal de general el plasma. Tots dos sistemes han estat optimitzats per la modificació de materials en pols. En el cas del reactor down-stream, s'ha estudiat a posició d'entrada del gas reactiu, la potència del generador i el temps de modificació per a tres tipus de tractament: oxigen, nitrogen i amoníac. En el cas del reactor de llit fluiditzat, els paràmetres que s'han estudiat han estat la distància entre la pols i la zona de generació de plasma, la mida de la partícula i la porositat de la placa suport.
Pel que fa a la modificació mitjançant la utilització de plasma atmosfèric, s'ha dissenyat un sistema que permet utilitzar una torxa de plasma atmosfèric comercial (Openair® de Plasmatreat GmbH) per tal de modificar materials en pols. Aquest sistema consisteix en un reactor adaptable a la torxa de plasma atmosfèric on té lloc la modificació, un sistema d'introducció de la pols dins de la zona de reacció així com també un sistema de refredament i col·lecció del material modificat que conjuntament permeten un funcionament quasi-continu del tractament.
S'ha utilitzat el reactor down-stream i el reactor a pressió atmosfèrica per tal de modificar tres tipus diferents de negre de carboni (N134, XPB 171 i Vulcan XC-72). D'altra banda, s'ha grafititzat i extret el N134 prèviament a la modificació per tal de realitzar un estudi sobre la influència de l'estructura superficial així com també de la presència d'impureses sobre la superfície del NC. L'oxidació i l'augment de nitrogen en superfície han estat les dues modificacions que s'han estudiat principalment per tal de comparar el resultat obtingut per les tècniques presentades.
El NC s'ha caracteritzat mitjançant diverses tècniques analítiques per tal de poder obtenir informació sobre els canvis produïts durant la modificació per plasma. Aquestes tècniques inclouen superfície específica, XRD, WAXS, STM per tal d'estudiar els canvis en la seva morfologia i estructura de la superfície. D'altra banda, per tal d'estudiar els canvis en la composició química s'han emprat mesures de pH, valoracions àcid/base i XPS.
Finalment, alguns dels negres de caboni modificats han estat seleccionats per tal de ser avaluats en aplicacions finals tal i com són el reforçament d'elastòmers i la seva activitat vers la reducció d'oxigen utilitzada en les PEMFC per tal d'eliminar els metalls nobles. En el primer cas, s'ha estudiat l'efecte sobre la cinètica i el mecanisme de vulcanització del negre de carboni modificat mitjançant el plasma atmosfèric. Aquest estudi s'ha dut a terme utilitzant dues tècniques complementaries com són les corbes reomètriques i la vulcanització de molècules model (MCV). També s'han realitzat mesures d'adsorció de polímer sobre el NC i Bound Rubber per tal d'estudiar la interacció polímer-càrrega la qual presenta una gran influència en les propietats finals dels materials. D'altra banda, s'ha estudiat també la capacitat del NC modificat vers a la reducció d'oxigen a partir de voltametria cíclica i s'han determinat les propietats del NC que poden influir de manera rellevant en l'activitat cataítica final del NC per a aquesta reacció. Tot i que es necessari fer una preparació posterior al tractament de plasma per a aquesta aplicació, el material final pot contribuir notablement a la eliminació de metalls nobles com a catalitzadors de reducció d'oxigen en les Piles de Combustible.
The present works deals with plasma modification of carbon black (CB). Although this type of treatment is widely used on flat surfaces handling problems should be overcome in order to treat powders as CB. In this study CB has been modified both by means of low-pressure and atmospheric pressure non-equilibrium plasmas. In order to accomplish this objective three different plasma reactors have been set-up; two at low pressure and one at atmospheric pressure working conditions.
Low pressure plasma reactors utilised in this work consist in a down-stream and a fluidised bed system working at Radio Frequency generation power (RF 13,56 MHz). Both reactors have been optimized to treat powder materials. For the down-stream reactor, position of the reactive gas inlet, and treatment conditions such as generator power and time have been studied for oxygen, nitrogen and ammonia treatments. For the fluidized bed reactor the distance of the powder sample to the plasma generation zone, particle size and support porosity have been taken into account.
Concerning atmospheric plasma, a device has been set up in order to adapt a commercial plasma torch (Openair® from Plasmatreat GmbH), for powder modification. An adaptable reactor, a method to introduce the powder in the plasma zone as well as a collecting system had been developed in order to obtain a quasi-continuous modification treatment.
Three types of CBs, N134, XPB 171 and Vulcan XC-72 have been modified in both the down-stream and the atmospheric plasma system. Graphitization and extraction of N134 were also carried out before plasma modification in order to study the effect of both impurities and surface structure of the CB during plasma modification. Surface oxidation and nitrogen enrichment were the two main studied treatments in both systems which allowed comparing their performances.
Unmodified and Modified CBs have been characterised from several points of view. Specific surface area, XRD, WAXS and STM have been used in order to study morphological and surface structure changes. On the other hand, pH measurements, acid/base titration and XPS were employed in order to study the surface chemistry composition changes that had taken place during plasma modification.
Some of the modified CB grades were selected in order to be tested in final applications such as rubber reinforcement and oxygen reduction non-noble metal catalyst for PEMFC. In the first case, the effect of atmospheric plasma treatment on the vulcanization kinetics and mechanism has been evaluated both by rheometre curves and the model compounding approach. Studies about the polymer-filler interaction have been also carried out by calculating bound rubber and adsorption from polymer solution. Last but not least, plasma modification capacity to enhance the oxygen reduction activity to obtain non-noble metal catalysts for PEMFC has been evaluated after the correspondent preparation. Oxygen reduction activity has been studied by means of cyclic voltammetry. The main CB properties which could play an important role in such applications have been analyzed.
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Connolly, Kevin John. "A coarse mesh radiation transport method for prismatic block thermal reactors in two dimensions." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/44823.
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In this paper, the coarse mesh transport method is extended to hexagonal geometry. This stochastic-deterministic hybrid transport method calculates the eigenvalue and explicit pin fission density profile of hexagonal reactor cores. It models the exact detail within complex heterogeneous cores without homogenizing regions or materials, and neither block-level nor core-level asymmetry poses any limitations to the method. It solves eigenvalue problems by first splitting the core into a set of coarse meshes, and then using Monte Carlo methods to create a library of response expansion coefficients, found by expanding the angular current in phase-space distribution using a set of polynomials orthogonal on the angular half-space defined by mesh boundaries. The coarse meshes are coupled by the angular current at their interfaces. A deterministic sweeping procedure is then used to iteratively construct the solution.
The method is evaluated using benchmark problems based on a gas-cooled, graphite-moderated high temperature reactor. The method quickly solves problems to any level of detail desired by the user. In this paper, it is used to explicitly calculate the fission density of individual fuel pins and determine the reactivity worth of individual control rods. In every case, results for the core multiplication factor and pin fission density distribution are found within several minutes. Results are highly accurate when compared to direct Monte Carlo reference solutions; errors in the eigenvalue calculations are on the order of 0.02%, and errors in the pin fission density average less than 0.1%.
7
Kamal, Rajit. "CFD simulation of mixing in a carbon black reactor : optimum geometry and momentum ratio." Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/11254.
Full text
8
Price, Richard D. "S-block metal chemistry of iminophosphoranes, phosphonium ylides and related systems : a synthetic and structural investigation." Thesis, Durham University, 1999. http://etheses.dur.ac.uk/4564/.
Full textAbstract:
This thesis details the synthesis and characterisation of s-block metal (lithium, sodium and magnesium) phosphonium ylide, R(_3)PCHR', and iminophosphorane complexes, R(_3)PNR', together with some related phosphine oxide, R(_3)PO, and sulfide, R(_3)PS, species, where R= Ph or Me(_2)N and R' = H, Me or Ph. The first three chapters of the thesis provide an introduction to the topic, with details of the experimental methods employed and results obtained. Chapter 4 presents a systematic study of Lewis base complexed s-block metal aryloxides, (ArOM L)(_2) where Ar = C(_6)H(_3)Ph(_2) or MeC(_6)H(_2)((^1)Bu)(_2), L = R(_3)PCHR', R(_3)PNR', R(_3)PO or R(_3)PS, and M = Li, Na, and (ArO)(_2)Mg(L)(_2) where Ar = MeC(_6)H(_2)(^1)Bu)(_2) and L = R(_3)PCHR’ or R(_3)PNR'. This includes a discussion of the single crystal XRD structures of the eight neutral ligands used, L, and ten new complexes containing either lithium or sodium. Chapter 5 describes the application of some related s-block metal ylide complexes, e.g. Ph(_3)PCHMe-LiN(CH(_2)Ph(_2))(_2) and Ph(_3)PCHMe-NaN(SiMe(_3))(_2), to the Wittig reaction, together with some solution-state and solid-state discussions (two single crystal XRD structures) of s-block metal amide-phosphonium ylide complexes, R(_3)PCHR'.MNR'(_2) where R = Ph or Me(_2)N, R’ = H or Me, and R" = SiMe(_3) or CH(_2)Ph Chapter 6 details a range of N-s-block metallated iminophosphorane complexes (e.g. Ph(_3)PNLi-LiBr.2thf and R(_3)PNMgX-L where R = Ph or Me(_2)N and L = Lewis base) their application to transmetallation reactions with copper(I) compounds, solution-state and solid-state NMR studies and six new single- crystal XRD structures. Chapter 7 describes some very recent work involving alkyldiphenylphosphonium ylides, MePh(_2)PCHPh, and imines, MePh(_2)PNPh, including a single crystal XRD structural study of the latter and three of its lithium derivatives, e.g. [CH(_2)LiPh(_2)PNPh](_4). Chapter 8 is concerned with a number of unexpected results, including the synthesis, solid-state structure and proposed mechanism of a novel A^-phosphino- iminophosphorane, Ph(_2)(C(_3)H(_4)Ph)PNP(C(_3)H(_5))Ph, and two aminophosphonium salts, [R(_3)PNH(_2)](^+)[OC(_6)H(_3)Ph(_2)]" where R = Ph or Me(_2)N.
9
Patel, Nikhil. "Studies On The Combustion And Gasification Of Concentrated Distillery Effluent." Thesis, Indian Institute of Science, 2000. https://etd.iisc.ac.in/handle/2005/274.
Full textAbstract:
The need for effective disposal of huge volumes of industrial waste is becoming more challenging due to expected imposition of stringent pollution control regulations in the near future. Thermochemical conversion, particularly gasification of organics in the waste is considered the best route from the perspective of volume reduction and prevalent eco-friendly concept of waste-to-energy transformation. It is considered imperative to have adequate understanding of basic combustion features as a part of the thermochemical conversion process, leading to gasification. The aim of this thesis is to understand the fundamental combustion processes associated with one of the top listed hazardous wastes from distilleries (Biochemical Oxygen Demand (BOD) ~ 40,000 - 50,000 mg/L), commonly known as vinasse, stillage or spent wash, through experiments and modeling efforts. Specially designed experiments on distillery effluent combustion and gasification are conducted in laboratory scale reactors.
As an essential starting point of the studies on ignition and combustion of distillery effluent containing solids consisting of 62 ± 2 % organics and 38 ± 2 % inorganics (primarily sugarcane derivatives), the roles of solids concentration, drop size and ambient temperature were investigated through experiments on (1) liquid droplets of 65 % and 77 % solids (remaining water) and (2) spheres of dried effluent (100 % solids) of size 0.5 mm to 20 mm diameter combusted at ambient temperatures of 773 to 1273 K. The investigation reveals that the droplets burn with two distinct regimes of combustion, flaming and char glowing. The ignition delay ‘t1’ of the droplets increased with size as is in the case of non-volatile droplets, while that of bone-dry spheres was found to be independent of size. The ‘t1’ decreased with increase in solids concentration. The ignition delay has showed an Arrhenius dependence on temperature. The initial ignition of the droplets and the dry spheres led to either homogeneous (flaming) or heterogeneous (flameless) combustion, depending on the ambient temperature in the case of sphere and on solid concentration and the ambient temperature, in the case of liquid droplets. The weight loss during the flaming combustion was found to be 50 - 80 % while during the char glowing it was 10-20 % depending on the ambient temperature. The flaming time tc is observed as tc~ d2c , as in the case of liquid fuel droplets and wood spheres. The char glowing time tc' is observed as tc ~ d2c as in the case of wood char, though the inert content of effluent char is as large as 50 % compared to 2 - 3 % in wood char. In the case of initial flameless combustion, the char combustion rate is observed to be lower. The heterogeneous char combustion in quiescent air in controlled temperature conditions has been studied and modeled using one-dimensional, spherico-symmetric conservation equations and the model predicts most of the features of char combustion satisfactorily. The measured surface and core temperatures during char glowing typically are in the range of 200 to 400 K and are higher than the controlled temperature of
the furnace.
Based on the results of single droplet combustion studies, combustion experiments were conducted in a laboratory scale vertical reactor (throughput ranging from 4 to 10 g/s) with the primary aim of obtaining sustained combustion. Spray of effluents with 50 % and 60 % solids (calorific value 6.8 - 8.2 MJ/kg), achieved by an air blast atomizer, was injected into a hot oxidizing environment to determine the parameters (ambient temperature and air-fuel ratio) at which auto-ignition could occur and subsequently studies were continued to investigate pre-ignition, ignition and combustion processes. Effluent with lower solids concentration was considered first from the point of view of the less expensive evaporator required in the field conditions for concentration and a spin-off in terms of better atomization consequently. Three classes of experiments were conducted: 1) Effluent injection from the wall with no auxiliary heat input, 2) Effluent injection with auxiliary heat input and 3) effluent injection within kerosene enveloping flame. Though individual particles in the spray periphery were found to combust, sustained spray combustion was not achieved in any of the three sets of experiments even with fine atomization. While conducting the third class of experiments in an inclined metallic reactor, sustained combustion of the pool resulting of accumulated spray seemed to result in large conversion of carbon. This led to the adoption of a new concept for effluent combustion in which the residence time is controlled by varying reactor inclination and the regenerative heat transfer from the product gases supplies heat for endothermic pre-ignition process occurring on the bed.
Combustion and gasification experiments were conducted in an inclined plate reactor with rectangular cross section (80 mm x 160 mm) and 3000 mm long. A support flame was found necessary in the injection zone in addition to the regenerative heat transfer. Effluent with 60% solids was injected as film on the reactor bed. This film disintegrated into fine particles due to induced aerodynamic stretching and shear stripping. Combustion of individual particles provided exothermic heat profile and resulted into high carbon
conversion. However, effluent clogging in the cold injection zone hindered system from attaining steady state. Effluent injected directly on the hot zone caused it to remain mobile due to the spheroidal evaporation and thus assuaging this problem. Improved mass distribution was achieved by displacing nozzle laterally in a cycle, actuated by a mechanism. Consistent injection led to sustained effluent combustion with resulting carbon conversion in excess of 98 %. The typical gas fractions obtained during gasification condition (air ratio = 0.3) were CO2 = 14.0 %, CO = 7.0 %, H2 = 12.9 %, CH4 - 1 % H2S = 0.6 - 0.8 % and about 2 % of saturated moisture. This composition varied due to variation in temperature (± 30 K) and is attributed to combined effect of local flow variations, shifting zones of endothermic processes due to flowing of evaporating effluent over a large area. In order to minimize this problem, experiments were conducted by injecting effluent at higher solids (73 % solids is found injectable). The effluent was found to combust close to the injection location-due to the reduced ignition delay and lower endothermic evaporation load helped raising the local temperature. This caused the pyrolysis to occur in this hottest zone of the reactor with higher heating rates resulting in larger yield of devolatilized products and improved char conversion. Effluent combustion was found to sustain temperature in the reactor under sub-stoichiometric conditions without support of auxiliary heat input and achieved high carbon conversion. These results inspired the use of higher concentration effluent, which is also known in the case of wood to have improved gasification efficiency due to reduction in moisture fraction. In addition, the recent studies on the sulfur emission in the case of black liquor combustion in recovery boilers have revealed that with increase in solids concentration, release of sulfur in gas phase is reduces. The required concentration can be carried out using low-grade waste heat from the reactor itself. It was found through experiments that, even though spray ignition occurred at this concentration, the confined reactor space prevented the spray from attaining sustained combustion. This led to the conduct of experiments in a new vertical reactor with adequate thermal inertia, essential to prevent variations in local temperature to reach a steady state gasification and required space to accommodate the spray.
The results of the experiments conducted in the vertical reactor in which effluents with 73 % solids, heated close to the boiling point and injected as fine spray in a top-down firing mode are consolidated and reported in the thesis in detail. Single particle combustion with enveloping faint flame was seen unlike stable flame found in coal water slurry spray combustion. Sustained gasification of gas-entrained particles occurred at reactor temperature in the range of 950 K - 1000 K and sub-stoichiometric air ratio 03 - 0.35 without the support of auxiliary fuel. The typical gas fractions obtained during gasification condition (air ratio = 0.3) were CO2 = 10.0 -11.5 %, CO - 10.0 - 12.0 %, H2 - 6.7 - 8.0 %, CH4 = 1.75 % H2S = 0.2 - 0.4 % and about 2 % of saturated moisture. The carbon conversion obtained was in the range of 95 - 96 %. These experiments have provided the conditions for gasification. The extraction of potassium salts (mostly sulfates, carbonate and chloride) from the ash, using a simple water leaching process, was found to recover these chemicals to as high an extent as 70 - 75 % of total ash.
In summary it is concluded that increasing the solid concentrations to as high levels as acceptable to the system (~ 75 %) and introducing as a fine spray of heated material (~ 363 K) into furnace with air at sub-stoichiometric conditions in a counter current combustion reactor will provide the frame work for the design of a gasification system for vinasse and similar effluent material.
The thesis consists of seven chapters. Chapter 1 introduces the problem and motivation of the work presented in the thesis. Literature review is presented in Chapter 2. The Chapter 3 deals with the single particle combustion studies. The results of effluent spray combustion experiments conducted in a laboratory scale vertical reactor are presented in Chapter 4. The results of combustion and gasification experiments conducted in another variant of a reactor, namely, inclined flat plate rectangular reactor is consolidated in Chapter 5. The results of gas-entrained spray gasification experiment of higher concentration effluent injected as spray in the vertical reactor are presented in Chapter 6. The general conclusions and scope for the future work are presented in the concluding chapter 7.
10
Patel, Nikhil. "Studies On The Combustion And Gasification Of Concentrated Distillery Effluent." Thesis, Indian Institute of Science, 2000. http://hdl.handle.net/2005/274.
Full textAbstract:
The need for effective disposal of huge volumes of industrial waste is becoming more challenging due to expected imposition of stringent pollution control regulations in the near future. Thermochemical conversion, particularly gasification of organics in the waste is considered the best route from the perspective of volume reduction and prevalent eco-friendly concept of waste-to-energy transformation. It is considered imperative to have adequate understanding of basic combustion features as a part of the thermochemical conversion process, leading to gasification. The aim of this thesis is to understand the fundamental combustion processes associated with one of the top listed hazardous wastes from distilleries (Biochemical Oxygen Demand (BOD) ~ 40,000 - 50,000 mg/L), commonly known as vinasse, stillage or spent wash, through experiments and modeling efforts. Specially designed experiments on distillery effluent combustion and gasification are conducted in laboratory scale reactors.
As an essential starting point of the studies on ignition and combustion of distillery effluent containing solids consisting of 62 ± 2 % organics and 38 ± 2 % inorganics (primarily sugarcane derivatives), the roles of solids concentration, drop size and ambient temperature were investigated through experiments on (1) liquid droplets of 65 % and 77 % solids (remaining water) and (2) spheres of dried effluent (100 % solids) of size 0.5 mm to 20 mm diameter combusted at ambient temperatures of 773 to 1273 K. The investigation reveals that the droplets burn with two distinct regimes of combustion, flaming and char glowing. The ignition delay ‘t1’ of the droplets increased with size as is in the case of non-volatile droplets, while that of bone-dry spheres was found to be independent of size. The ‘t1’ decreased with increase in solids concentration. The ignition delay has showed an Arrhenius dependence on temperature. The initial ignition of the droplets and the dry spheres led to either homogeneous (flaming) or heterogeneous (flameless) combustion, depending on the ambient temperature in the case of sphere and on solid concentration and the ambient temperature, in the case of liquid droplets. The weight loss during the flaming combustion was found to be 50 - 80 % while during the char glowing it was 10-20 % depending on the ambient temperature. The flaming time tc is observed as tc~ d2c , as in the case of liquid fuel droplets and wood spheres. The char glowing time tc' is observed as tc ~ d2c as in the case of wood char, though the inert content of effluent char is as large as 50 % compared to 2 - 3 % in wood char. In the case of initial flameless combustion, the char combustion rate is observed to be lower. The heterogeneous char combustion in quiescent air in controlled temperature conditions has been studied and modeled using one-dimensional, spherico-symmetric conservation equations and the model predicts most of the features of char combustion satisfactorily. The measured surface and core temperatures during char glowing typically are in the range of 200 to 400 K and are higher than the controlled temperature of
the furnace.
Based on the results of single droplet combustion studies, combustion experiments were conducted in a laboratory scale vertical reactor (throughput ranging from 4 to 10 g/s) with the primary aim of obtaining sustained combustion. Spray of effluents with 50 % and 60 % solids (calorific value 6.8 - 8.2 MJ/kg), achieved by an air blast atomizer, was injected into a hot oxidizing environment to determine the parameters (ambient temperature and air-fuel ratio) at which auto-ignition could occur and subsequently studies were continued to investigate pre-ignition, ignition and combustion processes. Effluent with lower solids concentration was considered first from the point of view of the less expensive evaporator required in the field conditions for concentration and a spin-off in terms of better atomization consequently. Three classes of experiments were conducted: 1) Effluent injection from the wall with no auxiliary heat input, 2) Effluent injection with auxiliary heat input and 3) effluent injection within kerosene enveloping flame. Though individual particles in the spray periphery were found to combust, sustained spray combustion was not achieved in any of the three sets of experiments even with fine atomization. While conducting the third class of experiments in an inclined metallic reactor, sustained combustion of the pool resulting of accumulated spray seemed to result in large conversion of carbon. This led to the adoption of a new concept for effluent combustion in which the residence time is controlled by varying reactor inclination and the regenerative heat transfer from the product gases supplies heat for endothermic pre-ignition process occurring on the bed.
Combustion and gasification experiments were conducted in an inclined plate reactor with rectangular cross section (80 mm x 160 mm) and 3000 mm long. A support flame was found necessary in the injection zone in addition to the regenerative heat transfer. Effluent with 60% solids was injected as film on the reactor bed. This film disintegrated into fine particles due to induced aerodynamic stretching and shear stripping. Combustion of individual particles provided exothermic heat profile and resulted into high carbon
conversion. However, effluent clogging in the cold injection zone hindered system from attaining steady state. Effluent injected directly on the hot zone caused it to remain mobile due to the spheroidal evaporation and thus assuaging this problem. Improved mass distribution was achieved by displacing nozzle laterally in a cycle, actuated by a mechanism. Consistent injection led to sustained effluent combustion with resulting carbon conversion in excess of 98 %. The typical gas fractions obtained during gasification condition (air ratio = 0.3) were CO2 = 14.0 %, CO = 7.0 %, H2 = 12.9 %, CH4 - 1 % H2S = 0.6 - 0.8 % and about 2 % of saturated moisture. This composition varied due to variation in temperature (± 30 K) and is attributed to combined effect of local flow variations, shifting zones of endothermic processes due to flowing of evaporating effluent over a large area. In order to minimize this problem, experiments were conducted by injecting effluent at higher solids (73 % solids is found injectable). The effluent was found to combust close to the injection location-due to the reduced ignition delay and lower endothermic evaporation load helped raising the local temperature. This caused the pyrolysis to occur in this hottest zone of the reactor with higher heating rates resulting in larger yield of devolatilized products and improved char conversion. Effluent combustion was found to sustain temperature in the reactor under sub-stoichiometric conditions without support of auxiliary heat input and achieved high carbon conversion. These results inspired the use of higher concentration effluent, which is also known in the case of wood to have improved gasification efficiency due to reduction in moisture fraction. In addition, the recent studies on the sulfur emission in the case of black liquor combustion in recovery boilers have revealed that with increase in solids concentration, release of sulfur in gas phase is reduces. The required concentration can be carried out using low-grade waste heat from the reactor itself. It was found through experiments that, even though spray ignition occurred at this concentration, the confined reactor space prevented the spray from attaining sustained combustion. This led to the conduct of experiments in a new vertical reactor with adequate thermal inertia, essential to prevent variations in local temperature to reach a steady state gasification and required space to accommodate the spray.
The results of the experiments conducted in the vertical reactor in which effluents with 73 % solids, heated close to the boiling point and injected as fine spray in a top-down firing mode are consolidated and reported in the thesis in detail. Single particle combustion with enveloping faint flame was seen unlike stable flame found in coal water slurry spray combustion. Sustained gasification of gas-entrained particles occurred at reactor temperature in the range of 950 K - 1000 K and sub-stoichiometric air ratio 03 - 0.35 without the support of auxiliary fuel. The typical gas fractions obtained during gasification condition (air ratio = 0.3) were CO2 = 10.0 -11.5 %, CO - 10.0 - 12.0 %, H2 - 6.7 - 8.0 %, CH4 = 1.75 % H2S = 0.2 - 0.4 % and about 2 % of saturated moisture. The carbon conversion obtained was in the range of 95 - 96 %. These experiments have provided the conditions for gasification. The extraction of potassium salts (mostly sulfates, carbonate and chloride) from the ash, using a simple water leaching process, was found to recover these chemicals to as high an extent as 70 - 75 % of total ash.
In summary it is concluded that increasing the solid concentrations to as high levels as acceptable to the system (~ 75 %) and introducing as a fine spray of heated material (~ 363 K) into furnace with air at sub-stoichiometric conditions in a counter current combustion reactor will provide the frame work for the design of a gasification system for vinasse and similar effluent material.
The thesis consists of seven chapters. Chapter 1 introduces the problem and motivation of the work presented in the thesis. Literature review is presented in Chapter 2. The Chapter 3 deals with the single particle combustion studies. The results of effluent spray combustion experiments conducted in a laboratory scale vertical reactor are presented in Chapter 4. The results of combustion and gasification experiments conducted in another variant of a reactor, namely, inclined flat plate rectangular reactor is consolidated in Chapter 5. The results of gas-entrained spray gasification experiment of higher concentration effluent injected as spray in the vertical reactor are presented in Chapter 6. The general conclusions and scope for the future work are presented in the concluding chapter 7.
Books on the topic "Reactor block"
1
Chuck, Lightfoot, ed. React: CIA black ops. Guilford, Conn: Lyons Press, 2004.
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2
Robin, Moore. React: CIA black ops. Guilford, CT: Lyons Press, 2004.
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3
U.S. Nuclear Regulatory Commission. Office of Nuclear Regulatory Research. Division of Systems Research., Idaho National Engineering Laboratory, and EG & G Idaho., eds. TRAC-B thermal-hydraulic analysis of the Black Fox boiling water reactor. Washington, DC: Division of Systems Research, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission, 1993.
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4
U.S. Nuclear Regulatory Commission. Office of Nuclear Regulatory Research. Division of Systems Research., Idaho National Engineering Laboratory, and EG & G Idaho., eds. TRAC-B thermal-hydraulic analysis of the Black Fox boiling water reactor. Washington, DC: Division of Systems Research, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission, 1993.
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5
U.S. Nuclear Regulatory Commission. Office of Nuclear Regulatory Research. Division of Systems Research., Idaho National Engineering Laboratory, and EG & G Idaho., eds. TRAC-B thermal-hydraulic analysis of the Black Fox boiling water reactor. Washington, DC: Division of Systems Research, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission, 1993.
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6
Simopoulos, A. Moessbauer studies of synthetic analogs simulating building blocks of nitrogenase reaction centers. Luxembourg: Commission of the European Communities Directorate-General Information Market and Innovation, 1985.
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7
Efremov, German. Modeling of chemical and technological processes. ru: INFRA-M Academic Publishing LLC., 2020. http://dx.doi.org/10.12737/1090526.
Full textAbstract:
In an accessible form, the textbook presents the theoretical foundations of physical and mathematical modeling; considers the modeling of mass, heat and momentum transfer processes, the relationship and analogy between them; studies the theory of similarity, its application in modeling, models of the structure of flows in apparatuses. Experimental-statistical and experimental-analytical modeling methods are also described, which include "black box" methods, planning passive, active full and fractional factor experiments, and adjusting models based on the results of the experiment. At the same time, modeling of chemical reactors, methods of optimization of chemical-technological processes, their selection, comparison and application examples are considered. Examples of modeling and optimization of processes in chemical, petrochemical and biotechnology on a computer in Excel and MathCAD environments are given. The appendices provide the basics of working in the MathCAD environment and elements of matrix algebra. Meets the requirements of the Federal state educational standards of higher education of the latest generation. It is intended for bachelors who are trained for the chemical, petrochemical, food, textile and light industries. It can be useful for specialists and undergraduates, as well as for scientists, engineers and postgraduates dealing with the problem under consideration.
8
Napoli, Museo nazionale di. Complete Unified Theory, Nirmalendu Das: Key words: mass of a photon & a graviton, unification of physics, value of Pi at excited state, unknown weight of radioactive elements, fission reaction of uranium, gamma ray burst, black hole properties through complete unified theory. Edited by De Petra Giulio and Italy Ministero dell'educazione nazionale. Bani Prokash (P) Limited, Panbazar, Guwahati -781001, Assam, India: G.P.Dev Choudhury, Bani Prokash (P) Limited, Panbazar, Guwahati - 781001, Assam, India in G.P.Dev Choudhury, Bani Prokash (P) Limited, Panbazar, Guwahati - 781001, Assam, India ., 1998.
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9
Conkling, John A. Chemistry of pyrotechnics: Basic priniciples and theory. New York: M. Dekker, 1985.
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10
Kane-Berman, John. Soweto: Black Revolt White Reaction. Ohio Univ Pr (Trd), 1986.
Find full textBook chapters on the topic "Reactor block"
1
Shimjith, S., A. Tiwari, and B. Bandyopadhyay. "Direct Block Diagonalization and Composite Control of Three-Time-Scale Systems." In Modeling and Control of a Large Nuclear Reactor, 101–14. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-30589-4_5.
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2
Jee, Eunkyoung, Suin Kim, Sungdeok Cha, and Insup Lee. "Automated Test Coverage Measurement for Reactor Protection System Software Implemented in Function Block Diagram." In Lecture Notes in Computer Science, 223–36. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-15651-9_17.
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3
Merentsov, N. A., N. S. Sokolov-Dobrev, and A. V. Persidskiy. "Calculation of Vibration Resistance of a Chemical Reactor High-Speed Shaft Undergoing Torsional Vibrations. Part I. Development of a Block Diagram and a Dynamic Transmission Model." In Lecture Notes in Mechanical Engineering, 759–67. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-54814-8_88.
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4
Krupenikov, Igori Arcadie, Boris P. Boincean, and David Dent. "Adsorption Capacity and Reaction." In The Black Earth, 33–35. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-0159-5_5.
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5
Pal Chaudhuri, Jyotirmoy. "British Reaction to the Firestone Investment in Liberia." In Whitehall and the Black Republic, 103–28. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-70476-0_4.
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6
Bao-zhong, Wang, Liu Kai-quan, Liu Ying, Zhang Wen-hui, and Zhao De-li. "Development of Mono-bloc Forging for CAP1400 Reactor Pressure Vessel." In Energy Materials 2014, 443–50. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-48765-6_52.
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Longo, Frank J. "Blocks to polyspermy and the cortical granule reaction." In Fertilization, 51–68. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4899-3264-8_6.
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Hu, B. L., Alpan Raval, and Sukanya Sinha. "Notes on Black Hole Fluctuations and Back-Reaction." In Black Holes, Gravitational Radiation and the Universe, 103–20. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-017-0934-7_7.
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Bao-Zhong, Wang, Liu Kai-Quan, Liu Ying, Zhang Wen-Hui, and Zhao De-Li. "Development of Mono-Bloc Forging for CAP 1400 Reactor Pressure Vessel." In Energy Materials 2014, 443–50. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2015. http://dx.doi.org/10.1002/9781119027973.ch52.
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Primachenko, Vladimir V., D. Valeriy V. Martynenko, D. Irina G. Shulik, Elena B. Protsak, D. Natalya G. Pryvalova, D. Vladimir I. Ivanovskiy, and Gennadiy V. Babich. "Investigation of Y2O3-Stabilized Zirconia Ramming Mix after Service in Carbon Black Reactor." In Proceedings of the Unified International Technical Conference on Refractories (UNITECR 2013), 1217–22. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2014. http://dx.doi.org/10.1002/9781118837009.ch206.
Full textConference papers on the topic "Reactor block"
1
Hrovat, Milan F., Karl-H. Grosse, and Richard Seemann. "Fabrication, Properties and Irradiation Performance of Molded Block Fuel Elements for HTGRs." In Fourth International Topical Meeting on High Temperature Reactor Technology. ASMEDC, 2008. http://dx.doi.org/10.1115/htr2008-58025.
Full textAbstract:
The molded block fuel element (FE) also called monolith is a molded body, consisting of a substantially isotropic highly crystalline graphite matrix, fuel regions within the same matrix and cooling channels. The fuel regions contain the fuel in the form of coated particles which are well bonded to the remaining graphite matrix, so that both parts of the block form a monolithic structure. The monolith meets the requirements for the very high temperature reactors attaining helium outlet temperatures above 1000°C. To fabricate the molded blocks FE demonstration plant was erected and put into operation. The equipment worked without malfunction. The produced block FEs meet the specifications of GA machined block FEs. All specimens and block segments irradiated at temperature up to 1600°C and max. fast fluence E > 0, 1 MeV of 11×1021 n/cm2 show perfect behaviour without any damage.
2
Sayers, Michael B., and Tara M. Dalton. "A Novel Contamination Free Two Temperature Continuous Flow Polymerase Chain Reactor." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-43055.
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Polymerase Chain Reaction (PCR) is an enzymatic process that has dramatically advanced many fields of life sciences, where it is an indispensable tool in a burgeoning range of applications, including diagnostic medicine, molecular biology, forensics and food testing. Recent increased demand for extremely high throughput PCR systems has led to the development of miniaturised continuous flow microfluidic PCR devices, which may have extremely high throughput compared to standard commercial PCR thermal cyclers. A novel continuous flow microfluidic PCR device has been designed and fabricated, consisting of two thermal zones maintained on aluminium thermal blocks providing the precise temperatures required for denaturation and annealing/extension. Polycarbonate sideplates retain the denaturation thermal block vertically above the annealing/extension thermal block while allowing for a variable air gap to be maintained between them. Heating of the denaturation thermal block is achieved using a Labview controlled Thermofoil heater, while the annealing/extension thermal block is maintained at temperature by optimised heat transfer from the denaturation block. Flow-through capillary tubing is positioned into a grooved serpentine channel machined into these thermal blocks. This serpentine channel passes through each thermal block fifty times, providing fifty PCR thermal cycles. Contamination free high throughput continuous flow PCR necessitates that the samples be encapsulated in an immiscible carrier fluid to eradicate cross contamination between samples and suppress the likelihood of the sample contacting the capillary leading to sample degradation. Encapsulation of the PCR reaction mixture is achieved upstream of the thermal cycler through segmentation of the sample into droplets entrained within an immiscible carrier fluid, which are then cycled through the thermal cycler. High throughput DNA amplification of two genes, GAPDH and LEF1, from the REH cell line has been successfully demonstrated on this microfluidic platform without any detectable contamination between samples. The PCR droplet reactors were approximately 250nl which is two orders of magnitude less than the standard sample size for most commercial PCR thermal cyclers.
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Venneri, Francesco, Yonghee Kim, Donald McEachern, Carl-Magnus Persson, and Chang-Keun Jo. "The Analysis of the Thorium-Fueled Modular Helium-Cooled Reactor." In Fourth International Topical Meeting on High Temperature Reactor Technology. ASMEDC, 2008. http://dx.doi.org/10.1115/htr2008-58315.
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The potential of thorium fertile fuel has been evaluated for a graphite-moderated MHR (Modular Helium Reactor) from the perspective of a self-sustainable U233-Th fuel cycle in the MHR. The 3-D core analyses have been performed with the thermal-hydraulic-coupled computer code systems (HELIOS-MASTER). The feasibility of a self-sustainable U233-Th fuel cycle in MHR was evaluated for a simplified equilibrium fuel cycle. A mixed oxide fuel (ThO2-UO2) was used. Whole-core analysis was performed with the MASTER code for various core configurations. In the core analysis, a 3-batch radial fuel shuffling scheme was adopted to find an equilibrium fuel cycle. Three types of fuel blocks were considered: a homogeneous fuel arrangement and two seed-blanket arrangements. It was found that a near self-sustainable U233-Th fuel cycle (conversion ratio = 0.95∼0.97) is feasible for the MHRs with the appropriate U-233 and Th-232 loadings. To achieve a high conversion ratio while maintaining a long cycle length, it is essential to maximize the thorium loading (∼30 tons) and at the same time soften the neutron spectrum to achieve sufficient reactivity. In order to achieve conversion ratios over 0.95 and an 18-month cycle length, the moderator volume needs to be increased with respect to the regular MHR design. Also, removing the inner graphite reflectors increases noticeably the core performance in terms of the conversion ratio and cycle length. A special seed-blanket block configuration (ISB, with seed and blanket fuels in the inner and outer regions of a block, respectively) provides a superior conversion ratio with respect to a homogeneously fueled block, whereas reversing the placement of seed and blanket in the ISB block configuration (with seed fuels in the outer zone) results in a worse performance. In the case of the U233-Th fuel cycle, the fissile (U233+U235) fraction in the discharged fuel is almost 90%. Denaturing of the uranium vector in the self-sustainable U233-Th fuel was investigated by adding 10% LEU in the fuel, to make the initial fissile fraction ∼20.5%. Neutronic analysis of the operation with denatured fuel reveals that the conversion ratio is substantially reduced and the available cycle length is much shorter.
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Slattery, Stuart R., Tamara L. Malaney, Scott J. Weber, Mark H. Anderson, Kumar Sridharan, and Todd R. Allen. "System for High Temperature Spectral Emissivity Measurement of Materials for VHTR Applications." In Fourth International Topical Meeting on High Temperature Reactor Technology. ASMEDC, 2008. http://dx.doi.org/10.1115/htr2008-58053.
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An experimental system for in situ high temperature measurements of spectral emissivity of VHTR materials has been designed and constructed. The design consists of a cylindrical block of silicon carbide with several machined cavities for placement of test samples, as well as a black body cavity. The block is placed inside a furnace for heating to temperatures up to 1000°C. A shutter system allows for selective exposure of any given test sample for emissivity measurements. An optical periscope guides the thermal radiation from the sample to a Fourier Transform Infra Red (FTIR) spectrometer which is used for real-time measurements of spectral emissivity over a wavelength range of 0.8μm to 10μm. To specifically address the needs of VHTR applications, the system has been designed for studies with VHTR grade helium environments and air transients. Inlet and outlet gas compositions are measured using a gas chromatograph, which in conjunction with ex situ analysis of the samples by electron microscopy and x-ray diffraction will allow for the correlation of surface corrosion of the materials and their spectral emissivities under different operating and accident conditions.
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Kim, Dong-Ok, Woo-Seok Choi, Keun-Bae Park, and Won-Jae Lee. "Dynamics and Responses of a Single Flexible Block on a Vibrating Floor." In 16th International Conference on Nuclear Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/icone16-48316.
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Graphite blocks constituting the reactor core of a typical prismatic type HTGR form a group of graphite block columns. The seismic analysis of a HTGR core structure composed of stacked prismatic graphite blocks has been an important design issue. In a tall column of stacked graphite blocks, the flexibility of blocks can not be ignored in the dynamic analysis. This paper proposes a dynamic model of flexible block and presents response analysis results of a single flexible block on a vibrating floor, and compared them to the classical ones of with a rigid assumption.
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Kim, Gyeongho, DongOk Kim, Woo-Seok Choi, Ji Ho Kang, and Jae Man Noh. "Dynamics Simulations of a Graphite Block Under Longitudinal Impact." In 18th International Conference on Nuclear Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/icone18-29683.
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Graphite blocks are important core components of the high temperature gas-cooled reactor. As these blocks are simply stacked in array, collisions among neighboring components may occur during earthquakes or accidents. Thus, it is important to develop a reliable seismic model of the stacked graphite blocks and have them designed to maintain their structural integrity during the anticipated occurrences. Various aspects involved in modeling and calculating impact-contact dynamics can affect the resulting behavior of the graphite block. These include mesh size, time step, contact behavior, mechanical constraint formulation of impact-contact analysis, etc. This work is dedicated to perform comparative studies and the effects of these parameters will be identified. The insights obtained through these studies will help build a realistic impact-contact model of the graphite block, from which a lumped or reduced dynamics model will be developed for the seismic analysis of the reactor including these graphite components.
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Rai, Yasuhiro, Kazuya Tatsumi, and Kazuyoshi Nakabe. "Experimental Study on a Compact Methanol-Fueled Reformer With Heat Regeneration Using Ceramic Honeycomb." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22742.
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On the way to a new era of our society which will be based on hydrogen energy, it is needed to develop on-site hydrogen production systems to cover current insufficient infrastructures of hydrogen supply network systems. For this, a highly efficient compact reformer can be one of the most suitable solutions for on-site production of hydrogen which is supplied to distributed electric power-generation systems. But, the local and overall energy balance in the reformer should be precisely controlled since the reforming reaction processes of hydrocarbon fuels are very sensitive to reaction temperature in the reformer. For smaller reformers, in particular, the amount of heat loss through the outer surfaces is large enough to dominate the reactions. An appropriate way for thermal energy management, therefore, is necessary to accomplish highly efficient reformers. For these backgrounds, a compact tubular-typed fuel reformer was fabricated in this study, and was applied to produce hydrogen from methanol, focusing on the partial oxidation reaction (POR). The reformer was composed of a stainless steel pipe as the reactor exterior and ceramic honeycomb blocks inserted in two locations of the reactor. The honeycomb blocks are expected to assist the reforming reactions and transfer the thermal energy of the exhaust gas to the reaction region, acting as a heat regenerator. The upstream-side honeycomb block was aimed to perform an effective heat exchange from the reactor wall to the reactant gas. By inserting the block, the reforming reaction became stable at right after the block. The maximum hydrogen production was achieved in the condition of equivalence ratio, around 3.5. The other honeycomb block was inserted in the downstream of the reaction zone to convert the thermal energy of exhaust gas to radiation energy which can be transferred to the upstream reaction region. Comparing to the case without the downstream-side block, the temperature of the reaction region became higher. Gas temperatures in the downstream region, on the other hand, became lower. Methanol conversion ratio and hydrogen production ratio enhanced due to the higher temperature at the reaction region. These results indicate that the thermal energy possessed by the exhaust gas was regenerated in the reaction region by the downstream-side honeycomb block and contributes to enhance the efficiency of the fuel reformer.
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Rai, Yasuhiro, Hideyuki Kogame, Kazuya Tatsumi, and Kazuyoshi Nakabe. "Experimental Study on a Compact Methanol-Fueled Reformer With Heat Regeneration Using Ceramic Honeycomb (2nd Report: Reaction Region Detection by a Positive Ion Current Probe)." In ASME 2011 Power Conference collocated with JSME ICOPE 2011. ASMEDC, 2011. http://dx.doi.org/10.1115/power2011-55377.
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A compact tubular-type fuel reformer was fabricated and operated under fuel-rich combustion conditions of methanol, focusing on the partial oxidation reaction (POR). Ceramic honeycomb strainer blocks were inserted in the reactor. In the authors’ previous study, Case-1 of only one honeycomb block insertion showed that the reaction region formed in the downstream of the block. This block worked as a reaction stabilizer. The other condition, Case-2, was operated with the secondary honeycomb block inserted in the downstream of the reaction region in addition to the first block. This geometrical structure sandwiched the reaction region between the two blocks, and the thermal energy possessed by the exhaust gas could be regenerated to the reaction region by radiation exchange between these two blocks, which resulted in enhancing the preheating of the premixed gas. By this effect, the methanol-conversion and hydrogen-production in Case-2 were enhanced by about 10% compared to Case-1. In the present study, the reaction characteristics of the fuel reformer were investigated in detail, by detecting the location of the reaction region. Detailed temperature profiles in the streamwise direction were measured with traversable thermocouples, and positive ion current distributions corresponding to the reaction region were measured with a Langmuir probe. It was confirmed by the both measurements that there exists a reaction region right after the first honeycomb block which accompanies with sharp temperature gradients. The estimated thickness of the reaction region, however, was as wide as several millimeters to a centimeter, which is believed to be a ‘mild reaction’ stabilized by the first honeycomb block. In Case-2, the high-temperature region became broader compared to Case-1, which indicates that the enhancement of preheating of premixed gas was achieved by the heat regenerated from the secondary honeycomb block.
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Demyanov, Aleksej Valeryevich, Nikolaj Aleksandrovich Krasavin, Mikhail Vladimirovich Nekrasov, and Dmitri Valeryevich Grachev. "CONTROL SYSTEM FOR FAST PULSED BLOCK OF BUSTER REACTOR." In Молодежь в науке. Саров: ФГУП «Российский федеральный ядерный центр – Всероссийский научно-исследовательский институт экспериментальной физики», 2022. http://dx.doi.org/10.53403/9785951505200_456.
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Shayer, Z., A. Baxter, and A. Shenoy. "Multi-Year Fuel Cycles in the MHR Core Using LEU/Th Fuel." In Fourth International Topical Meeting on High Temperature Reactor Technology. ASMEDC, 2008. http://dx.doi.org/10.1115/htr2008-58054.
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The current Modular Helium Reactor (MHR) fuel cycle uses fissile LEU (19.8 wt% U-235) and depleted uranium in separate TRISO particles, in a single fuel rod within a graphite matrix. The TRISO particle volume packing fraction (PF) in the fuel rods is 29%, of which the LEU particle PF is 62%. The lifetime between refuelings is about 476 effective full power days (EFPD). In this paper we assess the possibility of replacing the depleted uranium TRISO particles with thorium TRISO particles, and evaluate the impact of such replacement on fuel cycle length. A preliminary scoping study was performed to determine the most promising fuel rod/zoning configurations. The scoping study indicates that there is advantage to separating the thorium TRISO particles from the LEU particles at the fuel rod level instead of mixing them within a single rod. An axial checkerboard distribution of the fuel rods where all uranium and all thorium rods are interchangeable along the axial direction within the graphite block is the most promising configuration that was identified in this study and can be lead to a fuel cycle length extension of 50% to 80% relative to the current design, with only a modest increase in the fissile material loading (15%–20%). To this advantage can be added the benefit of a significant reduction in nuclear waste and in health risk. This study also lays the foundation for improving the fuel rod arrangement within the graphite block and the graphite blocks within the entire reactor core. The analysis is limited to a once-through fuel cycle based on in-situ fissioning of the U-233, without further separation and reprocessing.
Reports on the topic "Reactor block"
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Francesco Venneri, Chang-Keun Jo, Jae-Man Noh, Yonghee Kim, Claudio Filippone, Jonghwa Chang, Chris Hamilton, et al. High Temperature Reactor (HTR) Deep Burn Core and Fuel Analysis: Design Selection for the Prismatic Block Reactor. Office of Scientific and Technical Information (OSTI), September 2010. http://dx.doi.org/10.2172/991901.
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Michael A. Pope. High Temperature Reactor (HTR) Deep Burn Core and Fuel Analysis: Design Selection for the Prismatic Block Reactor With Results from FY-2011 Activities. Office of Scientific and Technical Information (OSTI), October 2011. http://dx.doi.org/10.2172/1042392.
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Goldie, James, and Reece Hooker, eds. Crowdwork pitfalls may need a (block)chain reaction. Monash University, May 2022. http://dx.doi.org/10.54377/27d8-2a2f.
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Forsberg, Charles, Piyush Sabharwall, and Andrew Sowder. Separating Nuclear Reactors from the Power Block with Heat Storage: A New Power Plant Design Paradigm. Office of Scientific and Technical Information (OSTI), November 2020. http://dx.doi.org/10.2172/1768046.
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Mandelli, Diego, Curtis Smith, Thomas Riley, John Schroeder, Cristian Rabiti, Aldrea Alfonsi, Joe Nielsen, Dan Maljovec, Bie Wang, and Valerio Pascucci. Light Water Reactor Sustainability Program Support and Modeling for the Boiling Water Reactor Station Black Out Case Study Using RELAP and RAVEN. Office of Scientific and Technical Information (OSTI), September 2013. http://dx.doi.org/10.2172/1115614.
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Rosseel, Thomas M., Mikhail A. Sokolov, Xiang Chen, and Randy K. Nanstad. Light Water Reactor Sustainability Program: Report on the Completion of the Machining of Zion Unit 1 Reactor Pressure Vessel Blocks into Mechanical and Microstructural Test Specimens and Chemical Analysis Coupons. Office of Scientific and Technical Information (OSTI), May 2018. http://dx.doi.org/10.2172/1471907.
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Forsberg, C. W., D. L. Moses, E. B. Lewis, R. Gibson, R. Pearson, W. J. Reich, G. A. Murphy, R. H. Staunton, and W. E. Kohn. Proposed and existing passive and inherent safety-related structures, systems, and components (building blocks) for advanced light-water reactors. Office of Scientific and Technical Information (OSTI), October 1989. http://dx.doi.org/10.2172/7023863.
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Stewart, A. K., C. E. Heinrich, and T. D. Hubbard. Dendrogeomorphic evidence of frequent mass movement using reaction wood in black spruce: Alaska Highway milepost 1267, Northway Junction, Alaska. Alaska Division of Geological & Geophysical Surveys, August 2017. http://dx.doi.org/10.14509/29734.
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Spiegel, Yitzhak, Michael McClure, Itzhak Kahane, and B. M. Zuckerman. Characterization of the Phytophagous Nematode Surface Coat to Provide New Strategies for Biocontrol. United States Department of Agriculture, November 1995. http://dx.doi.org/10.32747/1995.7613015.bard.
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Chemical composition and biological role of the surface coat (SC) of the root-knot nematodes, Meloidogyne spp. are described. SC proteins of M. incognita race 3 infective juveniles (J2) were characterized by electrophoresis and western blotting of extracts from radioiodine and biotin-labelled nematodes. J2 labelled with radioiodine and biotin released 125I and biotin-labelled molecules into water after 20 hours incubation, indicating that SC proteins may be loosely attached to the nematode. Antiserum to the principal protein reacted with the surface of live J2 and with surface proteins previously separated by electrophoresis. Human red blood cells (HRBC) adhered to J2 of several tylenchid nematodes over the entire nematode body. HRBC adhered also to nylon fibers coated with SC extracted from M. javanica J2; binding was Ca++/Mg++ dependent, and decreased when the nylon fibers were coated with bovine serum albumin, or pre-incubated with fucose and mannose. These experiments support a working hypothesis that RBC adhesion involves carbohydrate moieties of HRBC and carbohydrate-recognition domain(s) (CRD) distributed on the nematode surface. To our knowledge, this is the first report of a surface CRD i the phylum Nematoda. Gold-conjugated lectins and neoglycoproteins combined with silver enhancement have been used for the detection of carbohydrates and CRD, respectively, on the SC of M. javanica J2. Biotin reagents were used to trace surface proteins, specifically, on live J2. The labile and transitory nature of the SC was demonstrated by the dynamics of HRBC adherence to detergent-treated J2, J2 at different ages or fresh-hatched J2 held at various temperatures. SC recovery was demonstrated also by a SDS-PAGE profile. Monoclonal antibodies developed to a cuticular protein of M. incognita J2 gave a slight, but significant reduction in attachment of Pasteuria penetrans spores. Spore attachment as affected by several enzymes was inconsistent: alcian blue, which specifically blocks sulfyl groups, had no afffect on spore attachment. Treatment with cationized ferritin alone or catonized ferritin following monoclonal antibody caused significant decreases in spore attachment. Those results suggest a role in attachment by negatively charged groups.
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Moghimi, Gholamreza, and Nicos Makris. Response Modification of Structures with Supplemental Rotational Inertia. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, January 2024. http://dx.doi.org/10.55461/tihv1701.
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Tall, multistory, buildings are becoming increasingly popular in large cities as a result of growing urbanization trends (United Nations Department of Economic and Social Affairs 2018). As cities continue to grow, many of them along the coasts of continents which are prone to natural hazards, the performance of tall, flexible buildings when subjected to natural hazards is a pressing issue with engineering relevance. The performance of structures when subjected to dynamic loads can be enhanced with various response modification strategies which have been traditionally achieved with added stiffness, flexibility, damping and strength (Kelly et al. 1972; Skinner et al. 1973, 1974; Clough and Penzien 1975; Zhang et al. 1989; Aiken 1990; Whittaker et al. 1991; Makris et al. 1993a,b; Skinner et al. 1993; Inaudi and Makris 1996; Kelly 1997; Soong and Dargush 1997; Constantinou et al. 1998; Makris and Chang 2000a; Chang and Makris 2000; Black et al. 2002, 2003; Symans et al. 2008; Sarlis et al. 2013; Tena-Colunga 1997). Together with the elastic spring that produces a force proportional to the relative displacement of its end-nodes and the viscous dashpot that produces a force proportional to the relative velocity of its end-nodes; the inerter produces a force proportional to the relative acceleration of its end-nodes and emerges as the third elementary mechanical element (in addition to the spring and dashpot) capable for modifying structural response. Accordingly, in this report we examine the seismic performance of multistory and seismically isolated structures when equipped with inerters. In view that the inerter emerges as the third elementary mechanical element for the synthesis of mechanical networks, in Chapter 2 we derive the basic frequency- and time-response functions of the inerter together with these of the two-parameter inertoelastic and inertoviscous mechanical networks. Chapter 3 examines the response of a two-degree-of-freedom (2DOF) structure where the first story is equipped with inerters. Both cases of a stiff and a compliant support of the inerters are examined. The case of two parallel clutching inerters is investigated and the study concludes that as the compliance of the frame that supports the inerters increases, the use of a single inerter offers more favorable response other than increasing the force transferred to the support frame. Chapter 4 examines the seismic response analysis of the classical two-degree-of-freedom isolated structure with supplemental rotational inertia (inerter) in its isolation system. The analysis shows that for the “critical” amount of rotational inertia which eliminates the participation of the second mode, the effect of this elimination is marginal on the structural response since the participation of the second mode is invariably small even when isolation systems without inerters are used. Our study, upon showing that the reaction force at the support of the inerter is appreciable, proceeds with a non-linear response analysis that implements a state-space formulation which accounts for the bilinear behavior of practical isolation system (single concave sliding bearings or lead-rubber bearings) in association with the compliance of the support of the inerter. Our study concludes that supplemental rotational inertia aggravates the displacement and acceleration response of the elastic superstructure and as a result, for larger isolation periods (Tb > 2.5s) the use of inerters in isolation systems is not recommended. Chapter 5 first examines the response analysis of a SDOF elastoplastic and bilinear structure and reveals that when the yielding structure is equipped with supplemental rotational inertia, the equal- displacement rule is valid starting from lower values of the pre-yielding period given that the presence of inerters lengthens the apparent pre-yielding period. The analysis concludes that sup- plemental rotational inertia emerges as an attractive response modification strategy for elastoplastic and bilinear SDOF structures with pre-yielding periods up to T1 = 1.5sec. For larger pre-yielding periods (say T1 > 2.0sec), the effectiveness of inerters to suppress the inelastic response of 2DOF yielding structures reduces; and for very flexible first stories; as in the case of isolated structures examined in chapter 4, the use of inerter at the first level (isolation system) is not recommended. Finally, chapter 6 shows that, in spite of the reduced role of inerters when placed at floor levels other than the first level (they no-longer suppress the induced ground acceleration nor they can eliminate the participation of higher modes), they still manifest a unique role since it is not possible to replace a structure with solitary inerters at higher levels with an equivalent traditional structure without inerters.