Burnable absorber-integrated guide thimble (BigT) – II: application to 3D PWR core design

Yahya, Mohd-Syukri,Kim, Yonghee Atomic Energy Society of Japan 2016 Journal of nuclear science and technology Vol.53 No.10

<P>This paper is a companion to its immediate predecessor in the Burnable absorber-integrated Guide Thimble (BigT) series. It aims to demonstrate potential applications of the BigT concepts in a three-dimensional (3D) commercial pressurized water reactor core, which is based on the AP1000 first core design. The study specifically compares neutronic characteristics of the reference core against a BigT-loaded design. In this study, reactivity depletion patterns of nine fuel assembly lattices in the reference core were first evaluated. Corresponding sets of BigT-loaded assemblies that yield neutronically similar characteristics (i.e., initial reactivity suppression and depletion trend) with those of the reference assembly lattices were determined next. These BigT-loaded fuel assemblies were later loaded in place of the reference fuel assemblies for the subsequent high-fidelity 3D Monte Carlo core simulations. Results of the study clearly demonstrate that the BigT-loaded AP1000 first core performs as well as the reference core since all neutronic parameters are comparable, especially in terms of reactivity depletion, power peaking factors and shutdown margin. All simulations were completed using the Monte Carlo Serpent code with ENDF/B-VII.0 library.</P>

Low Thermal Conductivity of RE-Doped SrO(SrTiO3)1 Ruddlesden Popper Phase Bulk Materials Prepared by Molten Salt Method

Yulia Eka Putri,Suhana Mohd Said,Refinel Refinel,Michitaka Ohtaki,Syukri Syukri 대한금속·재료학회 2018 ELECTRONIC MATERIALS LETTERS Vol.14 No.5

The SrO(SrTiO3)1 (Sr2TiO4) Ruddlesden Popper (RP) phase is a natural superlattice comprising of alternately stackingperovskite-type SrTiO3layers and rock salt SrO layers along the crystallographic c direction. This paper discusses theproperties of the Sr2TiO4and (La, Sm)-doped Sr2TiO4RP phase synthesized via molten salt method, within the context ofthermoelectric applications. A good thermoelectric material requires high electrical conductivity, high Seebeck coefficientand low thermal conductivity. All three conditions have the potential to be fulfilled by the Sr2TiO4RP phase, in particular,the superlattice structure allows a higher degree of phonon scattering hence resulting in lowered thermal conductivity. In thiswork, the Sr2TiO4RP phase is doped with Sm and La respectively, which allows injection of charge carriers, modification ofits electronic structure for improvement of the Seebeck coefficient, and most significantly, reduction of thermal conductivity. The particles with submicron size allows excessive phonon scattering along the boundaries, thus reduces the thermalconductivity by fourfold. In particular, the Sm-doped sample exhibited even lower lattice thermal conductivity, which isbelieved to be due to the mismatch in the ionic radius of Sr and Sm. This finding is useful as a strategy to reduce thermalconductivity of Sr2TiO4RP phase materials as thermoelectric candidates, by employing dopants of differing ionic radius.

A Study on the Optimal Position for the Secondary Neutron Source in Pressurized Water Reactors

선정원,Mohd-Syukri Yahya,김용희 한국원자력학회 2016 Nuclear Engineering and Technology Vol.48 No.6

This paper presents a new and efficient scheme to determine the optimal neutron sourceposition in a model near-equilibrium pressurized water reactor, which is based on theOPR1000 Hanul Unit 3 Cycle 7 configuration. The proposed scheme particularly assignsimportance of source positions according to the local adjoint flux distribution. In thisresearch, detailed pin-by-pin reactor adjoint fluxes are determined by using the MonteCarlo KENO-VI code from solutions of the reactor homogeneous critical adjoint transportequations. The adjoint fluxes at each allowable source position are subsequently ranked toyield four candidate positions with the four highest adjoint fluxes. The study next simulatesex-core detector responses using the Monte Carlo MAVRIC code by assuming aneutron source is installed in one of the four candidate positions. The calculation isrepeated for all positions. These detector responses are later converted into an inversecount rate ratio curve for each candidate source position. The study confirms that theoptimal source position is the one with very high adjoint fluxes and detector responses,which is interestingly the original source position in the OPR1000 core, as it yields an inversecount rate ratio curve closest to the traditional 1/M line. The current work also clearlydemonstrates that the proposed adjoint flux-based approach can be used to efficientlydetermine the optimal geometry for a neutron source and a detector in a modern pressurizedwater reactor core.

Change of Phospholipid Species in Japanese Mustard Spinach Leaves during Senescence

( Daichi Nagaya ),( Daimon Syukri ),( Manasikan Thammawong ),( Kohei Nakano ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

In this study, a wide target analysis of phospholipid species in Japanese mustard spinach leaves stored for different durations was conducted by mass spectrometry, and phospholipid class distribution and fatty acid composition were compared for the purpose of identifying the freshness maker metabolites. Self-cultivated Japanese mustard spinach (Brassica rapa var. perviridis) leaves were harvested and stored for 4 and 7days at 20°C. Lipid in the leaves was extracted by a MTBE method and brought to liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The multiple reaction monitoring (MRM) program for a total 141 phospholipids was prepared and used for a highly sensitive detection. Peak area of MRM chromatogram for each phospholipid molecule were calculated and compared using t-statistics. The highest number of phospholipids (43) were detected on day 7 whereas 41 was found on day 0. Almost all the phosphatidylcolines (PC) and phosphatidylinositols (PI) increased during senescence, but the other phospholipid classes were found unchanged. Especially, PI (14:1/16:1) and PC (32:1) increased significantly and were suggested to be a potential freshness marker metabolite. Further study is needed to confirm these findings through the quantitative determination.

A Reduced-Boron OPR1000 Core Based on the BigT Burnable Absorber

Yu, Hwanyeal,Yahya, Mohd-Syukri,Kim, Yonghee Korean Nuclear Society 2016 Nuclear Engineering and Technology Vol.48 No.2

Reducing critical boron concentration in a commercial pressurized water reactor core offers many advantages in view of safety and economics. This paper presents a preliminary investigation of a reduced-boron pressurized water reactor core to achieve a clearly negative moderator temperature coefficient at hot zero power using the newly-proposed "Burnable absorber-Integrated Guide Thimble" (BigT) absorbers. The reference core is based on a commercial OPR1000 equilibrium configuration. The reduced-boron ORP1000 configuration was determined by simply replacing commercial gadolinia-based burnable absorbers with the optimized BigT-loaded design. The equilibrium cores in this study were directly searched via repetitive Monte Carlo depletion calculations until convergence. The results demonstrate that, with the same fuel management scheme as in the reference core, application of the BigT absorbers can effectively reduce the critical boron concentration at the beginning of cycle by about 65 ppm. More crucially, the analyses indicate promising potential of the reduced-boron OPR1000 core with the BigT absorbers, as its moderator temperature coefficient at the beginning of cycle is clearly more negative and all other vital neutronic parameters are within practical safety limits. All simulations were completed using the Monte Carlo Serpent code with the ENDF/B-VII.0 library.

In Vitro Propagation and Secondary Metabolite Production of Medicinal Plant of Euchresta horsfieldii (Lesch) Benn.

Andriyana Setyawati,Samanhudi Samanhudi,Wuri Prameswari,Daimon Syukri,Defrita Fitri Ramadhani,Okky Talitha 한국육종학회 2023 Plant Breeding and Biotechnology Vol.11 No.1

Euchresta horsfieldii (Lesch) Benn. is a highly demanded medicinal plant with many benefits. In vitro propagation through callus induction is an effective method for rapid multiplication in a short time. This research aimed to evaluate the effective concentration of Benzyl Amino Purine and 2,4-Dichlorophenoxiacetic acid on callus induction and organogenesis for in vitro propagation and secondary metabolite production of E. horsfieldii. The design used in this research was a Complete Randomized Design in 2 factors: Benzyl Amino Purine and 2,4-Dichlorophenoxiacetic acid with 5 levels for each concentration. Parameters observed are the percentage of inducted calluses, callus appearance time, the weight of fresh calluses, the weight of dry calluses, the texture of callus, the color of callus, percentage of the formed shoot, shoot appearance time, the height of shoots, the number of leaves, flavonoid compounds of callus, and bioactive compounds. The result showed that the single treatment of Benzyl Amino Purine and 2,4-Dichlorophenoxiacetic was significantly affecting the shoots forming. The concentration of 2,4-Dichlorophenoxiacetic 0 ppm gave the highest average plantlet height by 2.67 cm, increasing the number of shoots by 2.00, and the number of leaves by 5.60. E. horsfieldii cultured in vitro without additional growth regulators had a higher flavonoid content.