간행물

한국응용과학기술학회지 KCI 등재 The Korean Society of Applied Science and Technology

권호리스트/논문검색
이 간행물 논문 검색

권호

Vol.23 No.4 (2006년 12월) 11

1.
2006.12 구독 인증기관 무료, 개인회원 유료
Water quality has been deteriorated by the increasing amount of industrial waste water that is due to the better standard of living. In order to lessen the polluted water and substantially reutilize it at factories, a new method is needed. The plasma generator, which uses discharge current below 1,500 voltage and processes at extremely low temperature, has more strong oxidization than current method and an advantage of miniaturizing the apparatus in dealing with waster water by producing carrier gas at room temperature. This study were measured on the 3 kinds of waster water to the plasma generator for 120 minutes. As results, COD was almost decreased and removed in 15 minutes. The results suggest that the plasma generator can be used reduce COD and removal of color for various waster water, which can be reutilized as industrial water, It would be of benefit to the country like Korea in which qualified water is deficient.
4,000원
2.
2006.12 구독 인증기관 무료, 개인회원 유료
Multilayer adsorptions and BET adsorption are analyzed statistical-mechanically. Which ensemble is selected for the analysis is unimportant, because each ensemble yields the same results. However, the amount of mathematical manipulations and the matter of convenience vary from ensemble to ensemble. Hence, multilayer adsorptions and BET adsorption are examined using a canonical and a grand canonical ensembles, and an ensemble of subsystems. Also, the characteristics of multilayer and BET adsorptions are delineated.
4,000원
3.
2006.12 구독 인증기관 무료, 개인회원 유료
This article investigated to polymer-clay nanocomposite, especially in interfacial respect clay structure, its dispersion into polymer matrix, and clay modification is studied. The cationic exchange of surfactants with clay gallery results in preparing organo-clay capable of compatiblizing to monomer or polymer and increasing interlayer adhesion energy due to expansion of interlayer spacing. The orientation of surfactant in clay gallery is affected by chemical structure and charge density of clay, and interlayer spacing and volume is increased with alkyl chain length of surfactant, or charge density of clay. Also, the interaction between clay and polymer in preparing polymer-clay nanocomposite is explained thermodynamically. In the future, the study and development of polymer-clay nanocomposite is paid attention to the interfacial adhesion, clay dispersion within polymer, mechanism of clay intercalation or exfoliation.
4,000원
4.
2006.12 구독 인증기관 무료, 개인회원 유료
The esterification of palmitic acid in rapeseed oil and methanol emulsified by propylene glycol with PTSA(p-toluene sulfonic acid) was followed by the transesterification of rapeseed oil into biodiesel with 1(w/v)% GMS(glycerol monostearate) as an emulsifier using TMAH(tetramethyl ammonium hydroxide) catalysts at 60℃. The former reaction was optimized at the 1:20 of molar ratio of oil to methanol and 5wt% PTSA, and the latter was optimized at the 1:8 of molar ratio of oil to methanol and 0.8wt% TMAH. The overall conversion into biodiesel was 98% after 60min of reaction time at the 1:8 of molar ratio, 0.8wt% TMAH and 60℃. TMAH was a good catalyst to control the viscosity of biodiesel mixture.
4,000원
5.
2006.12 구독 인증기관 무료, 개인회원 유료
The pyrolysis of high density polyethylene(HDPE) and low density polyethylene(LDPE) was carried out at temperature between 425 and 500℃ from 35 to 80 minutes. The liquid products formed during pyrolysis were classified into gasoline, kerosene, gas oil and wax according to the petroleum product quality standard of Korea Petroleum Quality Inspection Institute. The conversion and yield of liquid products for HDPE pyrolysis increased continuously according to pyrolysis temperature and pyrolysis time. The influence of pyrolysis temperature was more severe than pyrolysis time for the conversion of HDPE. For example, the liquid products of HDPE pyrolysis at 450℃ for 65 minutes were ca. 30wt.% gas oil, 15wt.% wax, 14wt.% kerosene and 11wt.% gasoline. The increase of pyrolysis temperature up to 500℃ showed the increase of wax product and the decrease of kerosene. The conversion and yield of liquid products for LDPE pyrolysis continuously increased according to pyrolysis temperature and pyrolysis time, similar to HDPE pyrolysis. The liquid products of LDPE pyrolysis at 450℃ for 65 minutes were ca. 27wt.% gas oil, 18wt.% wax, 16wt.% kerosene and 13wt.% gasoline.
4,300원
6.
2006.12 구독 인증기관 무료, 개인회원 유료
In order to prepare high-solid coatings, first acrylic resins (HSAs) which contain 80% solid were synthesized, and then the prepared resins were cured with isocyanate at room temperature. In the synthesis of HSAs, viscosity, number average molecular weight (Mn) and conversion were 1372~2700 cps, 1520~1650 and 83~87%, respectively. Among the four kinds of initiators used, tert-amylperoxy-2-ethyl hexanoate was the most proper one in the synthesis of HSAs. With increasing Tg values, viscosity increased rapidly and molecular weight increased slowly. As a result of the examination of coated films, it was found that 60˚ specular gloss, impact resistance, heat resistance and cross-hatch adhesion were good, and pencil hardness, drying time and pot life were poor.
4,000원
7.
2006.12 구독 인증기관 무료, 개인회원 유료
The PU flame-retardant coatings (TTBAH, ATBAH-10C, -20C, and -30C) were prepared using the synthesized ATBAs and HDI-trimer as curing agent at room temperature. The physical properties of PU flame-retardant coatings with chlorine and phosphorus were inferior to those with phosphorus only and the properties were getting worse with increasing chlorine content. Flame retardancy was tested with three methods. With the vertical method, complete combustion time of ATBAHs were 259~347 seconds, which means that the prepared coatings are good flame-retardant. With the 45˚ Meckel burner method, char lengths of the three prepared coatings were less than 2.9 cm, which indicates that the prepared coatings are first grade. With the limiting oxygen index (LOI) method, the LOI values of the three prepared coatings were in the range of 30~35%, which proves good flame retardancy of the prepared coatings. from the result of flame retardancy tests of the specimens that contain the same amounts of flame retarding compounds. it was found that the coatings containing both phosphorus and chlorine show higher flame retardancy than the coatings containing only phosphorus. This indicates that there exists, some synergy effect between coexisting phosphorus and chlorine.
4,300원
8.
2006.12 구독 인증기관 무료, 개인회원 유료
The influences of fluorescence, scattering, and flocculation in turbid material by light scattering were interpreted for the scattered fluorescence intensity and wavelength, it has been studied the molecular properties by the spectroscopy of laser induced fluorescence (LIF). The effects of optical properties in scattering media have been found by the optical parameters(μs, μa, μt). Flocculation is an important step in many solid-liquid separation processes and is widely used. When two particles approach each other, interactions of several colloid particles can come into play which may have major effect on the flocculation and LIF process, The value of scattering coefficient μs is large by means of the increasing particles of scatterer it has been found that the slope decays exponentially as a function of distance from laser source to detector. It may also aid in designing the best model for oil chemistry, biopharmaceutical products, laser medicine and application of medical engineering on LIF and coagulation in particle transport mode.
4,000원
9.
2006.12 구독 인증기관 무료, 개인회원 유료
Generally, it has been known that positive plate efficiency is the most influential effect on the initial current capacity of lead acid battery. Thus, in this study, we have investigated the curing effect of the positive plate, which is one of the important lead acid battery processes. The curing process of the positive plate is performed either with the separation of each plate with 1mm gap or with no gap of plate. As a result, when there is no interval between each plate, the higher temperature current happened than expected, resulting in the changes in the initial current efficiency of the lead acid battery. The chemical composition and crystal structure of a material coated on the positive plate were identified with XRD and SEM. It was resulted that were only there not a lot of 4BS (tetrabasic-lead sulfate, 4PbO·PbSO4) on the plate in case of curing of plates without interval, but a large quantity of Pb3O4 also formed on the surface. On the other hand, it was observed that 3BS (tribasic-lead sulface, 3PbO·PbSO4·H2O) was the main product on the plate in case of typical curing process with some interval. From the initial current capacity test, the positive plate having 3BS was approximately 40% higher in initial current capacity than that having 4BS. It was concluded that 4BS and Pb3O4 on the plate surface were harmful to the initial current capacity of lead acid battery.
4,000원
10.
2006.12 구독 인증기관 무료, 개인회원 유료
[1,2,4]-Triazole derivatives were synthesized by 5 steps. Benzimidazole was refluxed with ethyl chloroacetate to give 1H-benzimidazole-acetic acid ethyl ester (1) over 52% yield. Ester (1) was refluxed with hydrazine hydrate in the presence of ethanol to afford 1H-benzimidazole-1-acetic acid, hydrazide (2). 5-Benzoimidazol-1-ylmethyl-4H-[1,2,4]triazole-3-thiol (4) was made via coupling of compound (2) with methyl isothiocyanate, followed by cyclization of 1H-benzimidazole-1-acetic acid, 2-[(methylamino) thioxomethyl]hydrazide (3) on reflux, and finally the target compounds (6a-6v) were synthesized by general substitution reaction. Compounds (6a-6v) were screened for T-type calcium channel blocker using the fluorescence assay by FDSS6000. All compounds (6a-6v) did not show better activities than control compound, mibefradil.
4,000원
11.
2006.12 구독 인증기관 무료, 개인회원 유료
This paper describes the experiments for investigating the effects of thermal stability of several commercial carpet mate materials. The melting point and thermal decomposition temperature was measured by means of a differential scanning calorimeter(DSC) in air condition. The DSC data and burning test results of nylon bulked continuous filament(N-BCF) yarn 100%, nylon(NY), polypropylene(PP), and a new material named polytrimethyleneterephthalate(PTT) were analysed to obtain the effect on their thermal stability. Conclusively, we observed that PTT and PP were approximately 380℃ and 240℃ to start the thermal decomposition, respectively. In other words, PTT is thermally the most stable material for carpet manufacturing.
4,000원