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Item Open Access SUPERSONIC JET GENERATION BY UNDERWATER SUB-MICROSECOND ELECTRICAL EXPLOSIONS OF WIRE ARRAYS(Physics of Plasmas, 2022) Maler, D.; Kozlov, M.; Efimov, S.; Krasik, Ya. E.Experiments in which supersonic water jets are generated by underwater sub-𝜇s timescale electrical explosions of cylindrical and conical wire arrays are presented. These are compared with previous experiments [Maler et al., Phys. Plasmas 28, 063509 (2021)] in which the generation of supersonic water jets was demonstrated using a 𝜇s timescale generator. Although in the present experiments less energy is deposited into the wire arrays, the water jets acquire higher velocities compared to when the deposited energy is higher but the timescale is slower. That is, with a higher energy density deposition rate, faster radial wire expansion is induced resulting in a stronger converging shockwave and a faster waterflow behind its front. In addition, two dimensional hydrodynamic numerical simulations show that the formation of the water jet is the result of extremely high pressure at the axis of the shockwave implosion and the cumulative edge effect realized at the array output.Item Open Access OSCILLATIONS OF RETAINING WALL SUBJECT TO GROB’S SWELLING PRESSUREAPPROACHES(Scientific Reports, 2022-07-18) Kozlov, Maksim; Tulendinova, Aizhan; Kim, Jong; Ellis, Grant; Skrzypacz, PiotrThe single-degree-of-freedom nonlinear problem describing the essential dynamics of an oscillating retaining wall based on non-quaking ground and subject to Grob’s swelling pressure is considered. The periodic solutions are derived using harmonic approximation. The amplitude-frequency relation is established by employing Lambert’s special function or alternatively using linearization of the nonlinear force. Analytical results are verified using numerical simulations.Item Open Access A NOVEL FRAMEWORK FOR SIMULATING PARTICLE DEPOSITION WITH MOVING BEDFORMS(Geophysical Research Letters, 2022) Teitelbaum, Yoni; Shimony, Tomer; Cifuentes, Edwin Saavedra; Dallmann, Jonathan; Phillips, Colin B.; Packman, Aaron I.; Hansen, Scott K.; Arnon, ShaiPrevious modeling studies of hyporheic exchange induced by moving bedforms have used a moving reference frame, typically corresponding to an individual moving bedform. However, this approach is not suitable for simulating the exchange and accumulation of immobile fine particles beneath moving bedforms, which commonly occurs in sand-bed streams, as both moving and stationary features must be considered. Here we present a novel simulation framework that may represent arbitrarily shaped, generally aperiodic mobile bedforms within a stationary reference frame. We combine this approach with particle tracking to successfully reproduce observations of clay deposition in sand beds, and the resulting development of a low-conductivity layer near the scour zone. We find that increased bedform celerity and filtration both lead to a shallower depth of clay deposition and a more compact deposition layer. While increased filtration causes more clay to deposit, increased celerity reduces deposition by flattening hyporheic exchange flowpathsItem Open Access CONTINUOUS SPECTRA OF LIGHT CHARGED PARTICLES FROM INTERACTION OF 30 MEV ENERGY PROTONS WITH COOPER(EPJ Web of Conferences, 2020-09) Zholdybayev, Timur; Mukan, Zhuldyz; Sadykov, Bakhtiyar; Duisebayev, Bek; Nassurlla, Maulen; Ismailov, Kairat; Kucuk, YaseminThis paper presents the experimental double-differential and integral cross sections of reactions (p,xp), and (p,xα) on natCu nucleus. The experiment with the protons, accelerated to energy of 30.0 MeV was performed at the isochronous cyclotron of Institute of Nuclear Physics (Kazakhstan). We investigated the adequacy of the theoretical models in explaining the measured experimental data and contributions of direct, preequilibrium and compound processes in the formation of the cross sections were determined. We assert that the traditional frameworks are valid for the description of the experimental data.Item Open Access BEDFORM SEGREGATION AND LOCKING INCREASE STORAGE OF NATURAL AND SYNTHETIC PARTICLES IN RIVERS(NATURE COMMUNICATIONS, 2021) Dallmann, J.; Phillips, C. B.; Teitelbaum, Y.; Cifuentes, Edwin Y. Saavedra; Sund, N.; Schumer, R.; Arnon, S.; Packman, A. I.While the ecological significance of hyporheic exchange and fine particle transport in rivers is well established, these processes are generally considered irrelevant to riverbed morpho dynamics. We show that coupling between hyporheic exchange, suspended sediment deposition, and sand bedform motion strongly modulates morphodynamics and sorts bed sediments. Hyporheic exchange focuses fine-particle deposition within and below mobile bedforms, which suppresses bed mobility. However, deposited fines are also remobilized by bedform motion, providing a mechanism for segregating coarse and fine particles in the bed. Surprisingly, two distinct end states emerge from the competing interplay of bed stabilization and remobilization: a locked state in which fine particle deposition completely stabilizes the bed, and a dynamic equilibrium in which frequent remobilization sorts the bed and restores mobility. These findings demonstrate the significance of hyporheic exchange to riverbed morphodynamics and clarify how dynamic interactions between coarse and fine particles produce sedimentary patterns commonly found in riversItem Open Access INVESTIGATION OF (P, XP) AND (P, XΑ) REACTIONS OF 30-MEV PROTONS WITH THE 103RH NUCLEUS(Jagiellonian University, 2020-01) Mukhamejanov, Y.; Alieva, G.; Alimov, D.; Kabdrakhimova, G.D.; Nassurlla, M.; Saduyev, N.; Sadykov, B.M.; Zholdybayev, T.K.; Ismailov, K.M.; Kucuk, Y.Double-differential and integral cross sections of the (p, xp) and (p, xα) reactions on the 103Rh nucleus were measured at Ep = 30 MeV using a proton beam delivered by the U-150M cyclotron of the Institute of Nuclear Physics (Almaty, Kazakhstan). A self-sustaining 103Rh foil of 3 µm thickness was used as a target. The obtained experimental results were compared with the TENDL-2019 nuclear data library, which provides the output of the TALYS nuclear model code. We assert that the TENDL-2019 evaluations provide a valid description of the obtained experimental data.Item Metadata only Optimization study on accelerator driven system design for effective transmutation of Iodine-129(Annals of Nuclear Energy, 2013-06-01) Ismailov, Kairat; Nishihara, Kenji; Saito, Masaki; Sagara, Hiroshi; Kairat, IsmailovAbstract The transmutation of Iodine-129 in accelerator driven system (ADS) is studied. The sodium iodide assembly loadings inside the core of ADS and in the surrounding core region are considered. The introduced concept of ADS with a power of 800MWt is able to transmute 250kg/y of minor actinides (MAs) and 46kg/y of Iodine-129 that supports ten PWRs. The initial loading masses of MAs and I-129 in ADS were equal to 3810kg and 824kg, respectively.Item Open Access Genre Analysis of 2 Research Reports; 3rd Year Undergraduate Research Report and a Research Article and Materials Design(Nottingham University, 2015) Ketteringham, MatthewGenre analysis has developed from earlier approaches to text analysis since the 1980s to influence EAP/ESP pedagogies based on the understanding that particular genres have particular communicative functions...Item Open Access Can the Use of the Course Management System Moodle Foster Learner Autonomy?(Nottingham University, 2015) Ketteringham, MatthewThe development of technology has challenged traditional classroom based teaching as the normal mode of instruction. Technology Enhanced Language Learning (TELL) has been seen as both an innovative new approach to teaching and at the same time a threat to institutionalised language learning (Benson & Voller, 1997; Benson, 2006). TELL has been linked to learner autonomy because of the possibility to enhance both ‘out-of-class’ learning and classroom environments....