• Journal of Pharmaceutical Investigation
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• v.27 no.3
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• pp.213-217
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• 1997

The present sustained-release terfenadine-pseudoephedrine HCl dosage form was the core tablet composed of outer (fast-release) layer containing 60 mg of terfenadine and l0mg of pseudoephedrine HCl, and inner (sustained-release) layer containing 110 mg of pseudoephedrine HCl. The purpose of this study was to investigate the possibility of formulating the terfenadine-pseudoephedrine HCl double-layered tablet which was bioequivalent to the core tablet. Its sustained-release and fast-release layer were formulated with disintegrating agents and polymers, respectively, varying with their kinds and amounts. The comparative dissolution test of double-layered and core tablet was carried out at pH 1.2, 4.0 and 6.8, leading to select composite of double-layered tablet whose dissolution pattern was similar to that of core tablet. It was composed of fast-release layer containing 60mg of terfenadine. 10 mg of pseudoephedrine HCl, sodium bicarbonate, microcrystalline cellulose and sodium starch glycolate, and sustained-release layer containing 110 mg of pseudoephedrine HCl and ethylcellulose/hydroxypropyl methylcellulose) (110/30 mg/tablet).

• YAKHAK HOEJI
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• v.41 no.1
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• pp.48-59
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• 1997

Sustained release matrix tablets, pellets, and coated pellets for the delivery of sulindac were prepared using cellulose derivatives at various ratios, and evaluated for the dis solution pattern. The release of sulindac, from matrix tablets prepared with low viscosity HPMC was relatively fast, and especially the tablets made of Metolose SM released all of sulindac within 1 hr. The release of drug from tablets made of other HPMC derivatives were retarded in the order of the following: Pharmacoat 645>Pharmacoat 606>Pharrnacoat 606+HPC-L>HPC-L. The most sustained release pattern was observed with the preparation of high viscous polymer. Metolose 90 SH. While release of sulindac, from matrix type pellet containing 10mg/cap of Metolose 90 SH or 60 SH was completed within 1 hr, a prolonged release formulation (30% in 1 hr) was obtained by the inclusion of EC. Pellets coated with HPMC showed a fast release pattern (${\geq}$ 80% within 2 hrs), whereas pellets coated with HPMC and EC (molar ratio 1 : 1) showed a sustained release pattern (${\geq}$ 80% in 12 hrs), vath the release from EC pellets being the most sustained. Fast (naked) and slow release pellets coated with EC, Metolose 60SH 50cps and propylene glycol. and enteric pellets coated with HPMCP 55 and Myvacet$^{\circledR}$ were prepared, and combined at various ratios for the assessment of dissolution pattern. The result indicates the possibility that the development of 24 hr sustained release delivery systems containing sulindac for oral administration could be achieved by means of combining sustained and fast release pellets at a proper portion.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.4
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• pp.545-550
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• 2011

Urea intercalated into montmorillonite (MT) exhibits remarkably enhanced N use efficiency, maintaining its fast effectiveness. This study dealt with the release property of urea from metal-urea-clay hybrid with MT (MUCH) under continuous-flow conditions and the cumulative impacts of its successive application on physicochemical properties of soils. Releases of urea were completed within 4 hrs under continuous-flow condition regardless of the types and the leaching solutions. However, urea release property was significantly affected by both the form of fertilizer and the presence of electrolytes in solution. The fast release property of urea from MUCH in continuous-flow condition was not significantly affected by soil properties such as soil pH and soil texture. In addition, its successive application did not lead to any noticeable change in soil physicochemical properties, water stable aggregate rate, water holding capacity and cation exchange capacity in both sandy loam and clay loam soils. Therefore, this study strongly supported that urea intercalated into MT could be applied as fast-effective N fertilizer, in particular for additional N supply.

• Archives of Pharmacal Research
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• v.15 no.2
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• pp.162-168
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• 1992

Release characteristics of five different types of hydrophilic albumin microspheres (HAM) containing different ratios of methotrexate-albumin (MTX-HSA) conjugates to free MTX: 1 : 0 (HAMC), 3 :1 (HAMC 3F), 1 :1 (HAMCF), 1:3 (HAMCF3) and 0 : 1 (HAMF) were investigated in the absence or presence of protease using dissolution tester. In all the HAMs studied except HAMC, the MTX was released bi-exponentially in the absence of protease; an initial fast release period up to approximately 6h, and thereafter the release rate was very much slower. The fast release of MTX from the HAMs (such as HAMC3F, HAMCF, HAMCF3 and HAMF) at the initial phase in probably due to the release of "physically associated" MTX from the core of the HAMs. The initial rate constants were 7.2, 8.7, 8.5 and 5.9 times greater than the second rate constants for HAMF, HAMCF3, HAMCF and HAMC3F, respectively. MTX release from HAMC was very slow and mono-phasic. It was at most 2.2% of the total entrapped amount by 24 h. The protease accelerated the release of MTX from the HAMs. The percentages of MTX released from HAMs up to 24 h were 100, 89.0, 75.0, 66.0 and 61.0% for HAMF, HAMCF3, HAMCF, HAMC3F and HAMC, respectively in the presence of protease and the corresponding values in the absence of protease were 30.2 19.0, 10.0, 6.5 and 2.2%, respectively. In vitro release of MTX in the presence of protease varied according to the ratios of MTX-HSA conjugates to MTX; the data set from HAMF, HAMCF3 and HAMCF fits better to monophasic first-order profile more adequately than to zero-order profile, that of HAMC3 monophasic first-order, and that of HAMC to bi-phasic zero-order. Above results suggested that zero-order release rate can be achieved by adjusting the ratio of MTX-HSA conjugates to MTX in the preparation of HAMs such as HAMC3F.as HAMC3F.

• Journal of the Institute of Convergence Signal Processing
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• v.14 no.4
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• pp.222-230
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• 2013

Retinal bipolar cells according to the light stimulus respond to potential slowly, emit neurotransmitter release(glutamine acid) to depend on membrane potential. In this paper, the several physiological information on neurotransmitter release mechanism in the presynaptic terminal of the ON-type bipolar cells are incorporated into the formula model. The source of fast components and slow components of neurotransmitter release was arranged in parallel, this model was able to reproduce the membrane potential and intracellular $Ca^{2+}$ concentration dependence of neurotransmitter release faithfully. In addition, because the fast releasable components of neurotransmitter was represented by the membrane potential dependence of trapezoid type, whereas the slow releasable components was represented by the membrane potential dependence of a bell type, $Ca^{2+}$ concentration rise in intracellular is suppressed by $Ca^{2+}$ buffer to reduce slow releasable components, it was confirmed that the membrane potential dependence of neurotransmitter release was characteristics of a trapezoid type. And, in the light response of ON type bipolar cell, the result of the simulation of the neurotransmitter release caused by the components of transient and persistent was that the start of light response occurred the fast release of neurotransmitter, it was confirmed that the transient component and persistent component of the light response occurred the slow release. It was confirmed that the later of persistent component of the light response occurred due to the continuous release by synaptic vesicle supplemented from the storage pool.

• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2395-2407
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• 2022

The sodium-cooled fast reactor is among the innovative nuclear technologies selected in the framework of the development of Generation IV concepts, allowing the irradiation of uranium-plutonium mixed oxide fuels (MOX). A fundamental step for the safety assessment of MOX-fuelled pins for fast reactor applications is the evaluation, by means of fuel performance codes, of the integral thermal-mechanical behaviour under irradiation, involving the fission gas behaviour and release in the fuel-cladding gap. This work is dedicated to the performance analysis of an inner-core fuel pin representative of the ASTRID sodium-cooled concept design, selected as case study for the benchmark between the GERMINAL and TRANSURANUS fuel performance codes. The focus is on fission gas-related mechanisms and integral outcomes as predicted by means of the SCIANTIX module (allowing the physics-based treatment of inert gas behaviour and release) coupled to both fuel performance codes. The benchmark activity involves the application of both GERMINAL and TRANSURANUS in their "pre-INSPYRE" versions, i.e., adopting the state-of-the-art recommended correlations available in the codes, compared with the "post-INSPYRE" code results, obtained by implementing novel models for MOX fuel properties and phenomena (SCIANTIX included) developed in the framework of the INSPYRE H2020 Project. The SCIANTIX modelling includes the consideration of burst releases of the fission gas stored at the grain boundaries occurring during power transients of shutdown and start-up, whose effect on a fast reactor fuel concept is analysed. A clear need to further extend and validate the SCIANTIX module for application to fast reactor MOX emerges from this work; nevertheless, the GERMINAL-TRANSURANUS benchmark on the ASTRID case study highlights the achieved code capabilities for fast reactor conditions and paves the way towards the proper application of fuel performance codes to safety evaluations on Generation IV reactor concepts.

• Journal of Pharmaceutical Investigation
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• v.41 no.1
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• pp.51-57
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• 2011

The objective of this study was to enhance the utilitization of Ibuprofen (IBU) by introducing the fast-disintegrating tablet (FDT) form. Presently, IBU is being widely used as a tablet or syrup form. But in contrast to these two formulations, IBU as FDT is not only convenient but also increases the control over the time release of the drug, noted by using Alginate beads. This study was carried out with Sodium Alginate and IBU at the ratios of 1:0, 1:0.5, 1:1, and 1:2 in order to produce a series of beads with different ratios. During the drying process of the beads, talc was added in beads to compare the effects with and without the talc. The final product was scanned with SEM imaging to determine the difference in the surface of the beads. The parameters assessed were the diameter, content assay, dissolution test and effectiveness of time-release. Direct compression method was used to prepare FDT containing IBU bead. The properties of FDT, such as hardness, disintegration time, were investigated. The dissolution profiles of FDT were tested using KP dissolution apparatus 1 (basket method). The results suggest addition of talc and drying the beads made the surface smooth and less vulnerable to clutter into chunks. The size of beads was less than 300 ${\mu}m$ which did not create a sandy feeling in the mouth. Thus, the beads formulation model made the sustained release of the drug possible, the hardness of FDT (1.25~1.50 $Kg/cm^2$) was acceptable and all the values of dissolving period were less than 30 seconds. The dissolution profile of FDT was same as that of IBU bead. The efficient dissolution profile and low price of IBU bead containing Sodium Alginate, the FDT formulation prepared from IBU bead can save the expenses and can improve the convenience of application of this drug.

• Journal of the Korea Society for Simulation
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• v.8 no.1
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• pp.63-76
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• 1999

Recently in manufacturing environment, manufacturing order is characterized by unstable market demand, shorter product life cycle, a variety of product and shorter production lead time. In order to adapt this manufacturing order, flexible manufacturing systems(FMS) in manufacturing technology advances into the direction that machines become further versatile functionally and that tools are controlled by fast tool delivery device. Unlike conventional FMS to mainly focus on part flow, it is important to control tool flow in single-stage multimachine systems(SSMS), consisting of versatile machines and fast tool delivery device. This research is motivated by the thought that exact estimation of tool competition at part release in SSMS enhances the system performance. In this paper, in SSMS under dynamic tool allocation strategy to share tools among machines, we propose real-time part release and tool allocation algorithms which can apply real factory and which can improve system performance.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.82.2-82.2
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• 2011

Major solar eruptive events, consisting of both a large flare and a near simultaneous fast coronal mass ejection (CME), are the most powerful explosions in the solar system, releasing $10^{32}-10^{33}$ ergs in ${\sim}10^{3-4}\;s$. They are also the most powerful and energetic particle accelerators, producing ions up to tens of GeV and electrons up to hundreds of MeV. For flares, the accelerated particles often contain up to ~50% of the total energy released, a remarkable efficiency that indicates the particle acceleration is intimately related to the energy release process. Similar transient energy release/particle acceleration processes appear to occur elsewhere in the universe, in stellar flares, magnetars, etc. Escaping solar energetic particles (SEPs) appear to be accelerated by the shock wave driven by the fast CME at altitudes of ~1 40 $R_s$, with an efficiency of ~10%, about what is required for supernova shock waves to produce galactic cosmic rays. Thus, large solar eruptive events are our most accessible laboratory for understanding the fundamental physics of transient energy release and particle acceleration in cosmic magnetized plasmas. They also produce the most extreme space weather - the escaping SEPs are a major radiation hazard for spacecraft and humans in space, the intense flare photon emissions disrupt GPS and communications on the Earth, while the fast CME restructures the interplanetary medium with severe effects on the magnetospheres and atmospheres of the Earth and other planets. Here I review present observations of large solar eruptive events, and future space and ground-based measurements needed to understand the fundamental processes involved.

• Journal of Pharmaceutical Investigation
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• v.16 no.1
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• pp.12-17
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• 1986

Etilefrine hydrochloride was microencapsulated with ethylcellulose by phase separation method to develop a sustained release dosage form. The results of dissolution test carried out with various microcapsules showed that the drug release was decreased with increasing the particle size of microcapsules at a constant core to wall ratio, and with decreasing the core to wall ratio. Also ethylcellulose 50 cps and fast stirring rate (900 rpm) was better in decreasing the drug release than ethylcellulose 22 cps and slow stirring rate (300 rpm), respectively.