• Journal of the Korean Society of Propulsion Engineers
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• v.6 no.3
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• pp.9-17
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• 2002

This Study is to investigate 8 composite propellants including Butacene and ${Bi_2}{O_3}$ by Shotgun/RQ Bomb test. Burning rate and mechanical properity are known to be major factors in determining the deflagrability of propellant. Propellant including over 5.5% Butacene(Ferrocene grafted HTPB) burned out over 135 m/s of impact velocity during Shotgun/RQ Bomb test. It was blown that Butacene was very sensitive material under high velocity impact. In the test results, propellants under 25mm/s in burning rate at 1500 psia could meet the requirements for IM of UN Test Series 7c(ii). Propellant deflagrabillity depends on burning rate at performance in the results of the present.

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.3
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• pp.62-69
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• 1998

Mechanical properties of polyethyleneglycol(PEG)/cyclo-tetramethylene tetranitramine(HMX) propellant were studied by adding polycaprolactone(PCP) and silane derivatives as coupling agent. Mechanical properties of the propellant were enhanced by increasing the content of PCP which was partially replaced with PEG. PCP/HMX propellant showed 17% increase in maximum tensile strength and 59% increase in elongation compared to those of PEG/HMX propellant. However, as the content of PCP was increased, the hydrolytic stability of this propellant was found to be deteriorated due to the ester group of PCP by measuring hardness drop of cured propellant and swell ratio difference of PEG/PCP binder stored at $40^{\cire}C$ and 90% relative humidity. Hardness of the PEG/PCP/HMX propellant was decreased with increasing triethoxysilyl propionitrile(TESPN) and dinitrosalicylic acid (DNSA) content from accelerated aging at $60^{\cire}C$.

• Analytical Science and Technology
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• v.24 no.6
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• pp.493-502
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• 2011

The catalyst works for visible-light region was characterized. Toluene, xylene, MEK and ammonia were used as reactants. The decomposition efficiency was compared between visible-light photocatalyst and UV-light one. UV-photocatalyst can be activated with UV-light wave length of 280~360 nm. However, visible-light photocatalyst can be activated with visible wave length of 400~750 nm. This result was found by using UV-Vis absorbance. A lot of materials were doped to visible light photocatalyst in order to increase its performance. Platinum was added to visible light photocatalyst with manganese in order to increase performance of the visible light photocatalyst. MTMS (Methyl tri methoxy silane) was used as a binder. Contact angle was analyzed varying with amount of binder. Contact angle was increased with increasing the amount of MTMS. As a result, the hydrophilic property of photocatalyst with MTMS binder was decreased due to its hydrophobic one. And Mn-$TiO_2$ catalyst had an excellent anti-bacterial property.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.417-421
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• 2005

Novel two synthetic technics using cationic ring-opening copolymerization of tetrahydrofuran (THF) and ethylene oxide (EO), or just polymerized EO on Poly-THF, could lead to random hydroxyl-terminated poly(EO-ran-THF) or tri-block PEG-PTHF-PEC, respectively. These reactions were carried out using $BF_3O(C_2H_5)_2$ as catalyst, 1,4-butanediol or PTHF as diol initiator. Copolymer structures were controlled by monomer feed ratio, or initial PTHF and EO monomer added amount. The molecular weight of polymer was merely dependant on the ratio of [monomer]/[diol], but not on catalyst. Well-defined random and block hydroxyl-terminated copolyether was found to be as the prepolymer for the propellant binder from the experiment to polyurethane with them.

• Journal of the Korea Concrete Institute
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• v.27 no.2
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• pp.177-184
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• 2015

In order to use the high-volume slag cement as a construction materials, a proper activator which can improve the latent hydraulic reactivity is required. The dissolved aluminum silicon ions from ground granulated blast furnace slag (GGBFS) react with sulfate ions to form ettringite. The proper formation of ettringite can increase the early-age strength of high-volume GGBFS (80%) cement. The aim of this study is to investigate the hydration properties with sulfate activators (sodium sulfate, anhydrite). In this paper, the effects of $Na_2SO_4$ and $CaSO_4$ on setting, compressive strength, hydration, micro-structure were investigated in high-volume GGBFS cement and compared with those of without activator. Test results indicate that equivalent $SO_3$ content of 3~5% improve the early-age hydration properties such as compressive strength, heat evolution rate, micro-pore structure in high-volume GGBFS cement.

• Korean Chemical Engineering Research
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• v.51 no.3
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• pp.352-357
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• 2013

In this study, the pellet-type adsorbents were prepared by extrusion using water treatment sludge. Effects of binder and calcination on physical and chemical properties of pellet-type adsorbents were investigated. The porous structure and surface characteristics of the adsorbents were studied using nitrogen adsorption, compression strength, scanning electron microscope, X-ray diffraction, and infrared spectroscopy of adsorbed pyridine. With increasing of binder content to 5 wt%, the compressive strength of pellet-type adsorbent could be improved more than three times, but the surface area reduced by 30%, and thus the breakthrough time of trimethylamine was shortened. The breakthrough time of the trimethylamine, a basic gas, could be increased more than three times through calcination, which seems to be due to generation of acid sites composed of Lewis acid and Br$\ddot{o}$nsted acid sites on the adsorbent surface.

• Resources Recycling
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• v.7 no.4
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• pp.35-42
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• 1998

Surface mount technology is the biggest theme in the area of deιIronic component. To miniatunze an electronic component, s such as ferrite chip inductor, the cer뼈lic wet process for green-sheet lamination and/or screen printing method through a s solvent medium system is widely used. The preparation and characterization of NiCuZn Ferrite (NCZF) shurry and the green s sheet using the water mixed binder system has been studied. The 21 vol% of NCZF slurry was prepared by a ball milling. The p polyacrylic vinyl copolymer (Mw; 60,000) was used as a binder. Th$\xi$ mixture of distilled water, isopropyl alcohol (IPA) and 2l butoxy ethanol was used as a dispersion medium. The water content of medium varied from about 40% to 80%. As the results. Thc disp$\xi$rston stability of the NCZF slurry was attributed to the free polymer rather than the electrostatic force of the particle. T The viscosity of the NCZF slurry was greatly depended on the ratio of water content in the medium.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.87-92
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• 2010

This study evaluates the laboratory properties of asphalt binder and mixture modified with R-EPDM(Recycling Ethylene Propylene Dien Monometer), which consists of R-EPDM as a main ingredient that is an industrial by-product made by manufacturing waste EPDM below 50 mesh as an additive. Superpave system was used to determine the PG(Performane Grade) and evaluate the property of R-EPDM modified binder. OACs(Optimum Asphalt Contents) of R-EPDM modified asphalt mixtures were determined by Superpave mix design using gyratory compactor and wheel tracking test and moisture susceptibility test were carried out with R-EPDM modified asphalt mixtures at OACs. The results from these tests, rutting-resistance and freezing and thawing resistance by moisture susceptibility of R-EPDM modified asphalt mixtures were superior to one of general asphalt mixtures(AP-5).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.12
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• pp.1112-1117
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• 2006

The properties of LTCC green tape with addition of binder were investigated in order to understand an effects of binder on multilayer processing. A green sheet form was fabricated through tape casting method with the MLS-22 powder. The lamination density increased with increasing amount of binder and lamination pressure. With increasing amount of binder, the elongation of ceramic sheets increased but the tensile stress and air-permeability decreased. The addition of excessive binder is caused defects in the green sheet during via hole punching. The optimum condition of the via hole without defects was observed from amount of the binder 10 wt%.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.1
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• pp.29-34
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• 2011

Hydroxyl terminated polyether(HTPE) propellants have been developed recently as possible replacements for HTPB/AP propellants currently used in a number of tactical rocker motor. As analyzing friability of HTPE and HTPB propellants in this study, the following results could be derived. The friability of the tested propellants depended on its binder contents, mechanical property, and burning rate. It was decreased as burning rate was lowered and toughness was increased.