• 상하수도학회지
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• 제19권5호
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• pp.625-631
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• 2005

Disinfection characteristics of mixed oxidants produced by mean of electro-chemical method were evaluated. Inactivation rate of B. subtilis spore on the mixed oxidants were similar with that of chlorine. Based on the experimental results, activation energy of mixed oxidants and chlorine with B. subtilis spore at pH 8.3 were calculated as 30.8, $34.7kJ{\cdot}mol^{-1}$ respectively. UV absorption spectrum of both chlorine and mixed oxidants present similar. Molar extinction coefficients of chlorine and mixed oxidants at 292nm, which is maximum absorption wavelength of $OCl^-$ were 357, $377M^{-1}cm^{-1}$, respectively. Disinfectant decay rate and formation rate of THM in the S WTP filtrate also shows insignificant difference for both mixed oxidants and chlorine. In consequent, it was confirmed that high portion of chlorine presents in the mixed oxidants.

• 수산해양기술연구
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• 제11권1호
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• pp.8-14
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• 1975

The optical properties of the sea water were studied by use of underwater lux-meters in the coastal waters of Busan from May to November 1975. The absorption coefficient of the sea water in the area ranges from O. 169 to 1. 049 and the mean absorpflOn coefficient is 0.413. Maximum monthly mean absorption coefficient (0. 56) was observed in August, while the minimum was O. 338 in September. There was a distinct discontinuity layer of the absorption coefficient in accordance with the thermocline and the halocline in summer. The mean transparency of the area was 3. 8 meters, and transparency in autumn was higher than that in summer. The relation between absorption coefficient (m) and transparency (D) was deduced, m=1. 57/ D. The rate of light penetration at 5 m-layer of sea water was 2. 5 percent when the solar altitude was six degree in July 1975.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1997년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 1997
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• pp.217-224
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• 1997

One way in which a comparison can be mode between various reinforced concrete structures is to compare the rate of energy absorption capacity. It is useful to use a well-known standard hysteretic rule as a benchmark for comparisons. The concept of energy absorption efficiency with respect to an elaste-perfectly plastic (EPP) system has been adopted. The normalized cumulative energy, cumulative plastic drift and energy response spectra are used for the method. The previous study using the energy spectra developed by Chang and Mander (1994) indicates the cumulative plastic demand for most earthquakes to be 0.1 rad., but a conservative upper bound of 0.2 rad. could be expected for a maximum credible earthquake. From the present study, the energy absorption efficiency in R.C. structures with respect to the EPP system may range in 30%-45% for most cases.

• 한국식품영양학회지
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• 제2권1호
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• pp.18-26
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• 1989

The objective of this study was to improved the limited functional characteristics of mungbean whole globulin. The mungbean whole globulin was acylated with succinic and acetic anhydride, and the functional properties of acylated protein were investigated, The results obtained ware as follows. 1. The UV-absorption spectra of acylated whole globulins with that of the succinylated 74% whole globulin as large blue shift of the absorption maximum and minimum wavelength from 275 nm to 269 nm, respectively. 2. The mobility of acylated whole globulin were increased on PAGE pattern, and degree of mobility was particularly remarkable in case of succinylation, 3. The water absorption capacity of whole globulin was increased by acylation. The most increased rate of whole globulin was 174,02% from succinylated 74%. The oil absorption capacity of whole globulin was increased by acylation The most increased rate of whole globulin was 165.41% from acetylated 81.77%. 4. The bulk density of whole globulin was decreased by acylation. and the greater the extent of acylation, the smaller the bulk density. 5. The foaming capacity and stability of whole globulin was increased by acylation, and remarkably high in 74% succinylated whole globulin. In contrast, however, the foaming capacity and stability of native and acylated whole globulin were decreased by heat treatment.

• Journal of Pharmaceutical Investigation
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• 제26권2호
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• pp.91-98
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• 1996

Precipitation was formed during the preparation of decoction from a mixure of Scutellariae Radix and Coptidis Rhizoma or Phellodendri Cortex according to the prescription of Hwang-ryean-hae-dog-tang. Baicalin and berberine, the active ingredients of the two herbal medicine were identified in coprecipitated product. Pills were prepared using the coprecipitated product and various binders. The dissolution rate of baicalin and berberine from pills was increased in at pH1.2 when acacia or tragacanth was used. The absorption rate of baicalin from the coprecipitated product was faster than that from Scutellaria extract, but the absorption of berberine from CPP was slower in stomach, duodenum and jejunum of rats compared with Coptis extract. The time required for the maximum serum concentration (Cmax) of baicalin and berberine from CPP in mice were 150 and 200 min after oral administration, respectively. The maximum serum concentration of baicalin from CPP in mice was higher than Scutellaria extract, but the concentration of berberine was lower compared with Coptis extract. The minimum inhibitory concentration of CPP was below $50\;{\mu}g/ml$ against gram positive bacteria, and was higher than that against gram negative bacteria. The antibacterial activity of CPP was lower than that of herberine, but was more potent than Scutellaria extract. It was found that the inhibition rates of growth by CPP against S. epidermidis, K. pneumoniae, B. cereus and S.aureus were 60.0, 51.1, 45.4 and 39.9%, respectively.

• 약학회지
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• 제30권6호
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• pp.288-293
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• 1986

Effects of phenobarbital on the pharmacokinetics of griseofulvin were studied in rats. Phenobarbital was administered orally for five days at the dose of 75mg/kg/day. Absolute bioavailability of oral griseofulvin was significantly(p<0.005) reduced but total clearance(CL$_s$ was not changed by phenobarbital pretreatment. Absorption rate constant(K$_a$ and maximum plasma concentration(C$_{max}$) were significantly(p<0.05) reduced, and time to reach maximum plasma concentration(T$_{max}$) of griseofulvin was significantly(p<0.05) increased by phenobarbital pretreatment. Changed pharmacokinetics of griseofulvin seemed not to be due to induced enzyme activity by phenobarbital but to reduced GI absorption of griseofulvin.

• Journal of the Korean Wood Science and Technology
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• 제10권3호
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• pp.133-134
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• 1982

This experiment has been made to investigate the absorption of watersoluble zinc chloride by Pinus densiflora S. et Z. at different moisture content, under soaking process, to decide the optimum content condition for the maximum absorption of zinc chloride by the wood tested and to investigate the concentration of zinc chloride affecting each moisture content of wood. Material was cut in the Dept. of Forest, College of Agr. S.N.U. Suwon, Korea. Sample was divided into sap and heartwood group and cut $2{\times}2{\times}2\;cm$ in size, having exact three dimensions, using the part of D.B.H. The numbers of sample were 20 pieces for each moisture content condition for both sap and heartwood. Especially, the samples were protected from exposure to keep moisture content in green condition. The ranges of moisture content tested were as the table 3 and 4. The conclusions were as follows: 1. With 3% zinc chloride solution, the rate of absorption decreased with the time increased, if the air seasoned Korean red pine (Pinus densiflora S. et Z.) was treated in steeping process. Initial absorption for 30 minutes was more than 50% of total absorpon for 24 hours. 2. Rate of absorption was same under the green condition, while rate of absorption under the moisture content 7 to 30% varied. 3. Although it was not quite proportional change in the absorption with the difference of moisture content, the great change in the absorption occured by seasoning. With exception sap green condition, sapwood twice more permeable than the heartwood in the oven dried condition and it has been observed the nearly same amount of absorption at the moisture content of 7%, 10% and 15% respectively in heartwood. 4. It was better from water in wood from view-point of absorption of zinc chloride solution, but it was difficult practically to obtain the smallest moisture content, and then it was decided that values of allowable moisture content, on the basis of mean absorption, were 15% to 20% in the sapwood, and in the heartwood, 10% to 15%. The mean absorption for each moisture content in the sap and the heartwood were as following. 5. In general, the concentration of zinc chloride after steeping was nearly same between moisture content and sap and heartwood respectively.

• 대한기계학회논문집B
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• 제22권4호
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• pp.489-498
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• 1998

Among the heat/mass exchange units composing an absorption system, the absorber, where the refrigerant vapor is absorbed into the liquid solution is the one least understood. In the present study, the effects of non-absorbable gas on the absorption process of aqueous lithium bromide solution falling film inside a vertical tube were experimentally investigated. In the range of film Reynolds number of 30 ~ 195, heat and mass transfer characteristics were investigated as a function of non-absorbable gas volumetric concentration, 0.2 ~ 20%. An increase of non-absorbable gas volumetric concentration degraded the mass transfer rate dramatically in the absorption process. The reduction of mass transfer rate was significant for the addition of small amount of non-absorbable gas to the pure vapor. At film Reynolds number of 130, an increase of non-absorbable gas concentration from 0.2 to 6.0% resulted in the decrease of mass transfer rate by 36% and 20% of non-absorbable gas by 59%. However the decrease of film Nusselt number with the increase of volumetric concentration of non absorbable gas was relatively smaller than the decrease of Sherwood number. Critical film Reynolds number was identified to exist for the maximum heat and mass transfer regardless of the volumetric concentration of non-absorbable gases.

• Journal of Pharmaceutical Investigation
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• 제19권2호
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• pp.93-98
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• 1989

The study was performed to compare the dissolution, diffusion and absorption characteristics using Sartorius dissolution and absorption simulator and in vivo bioavailability of commercially available rifampicin capsules. Both brands C and F showed similar dissolution patterns and absorption properties through artificial gastric barrier in Sartorius simulator. Diffusion rate constants through the membrane of brands C and F were $3.04\;{\times}40^{-3}$ and $2.88\;{\times}\;10^{-3}cm/min$, respectively. Rifampicin capsules were administered orally to six fasted healthy volunteers according to cross-over design. The pharmacokinetic parameters between brands C and F, maximum plasma drug concentration$(C_{max})$, the time to reach $C_{max}$, absorption rate constant and area under the curve $(AUC_{0-24hr})$, elimination rate constant, and amount of drug excreted in urine were 6.11 and $7.27\;{\mu}g/ml$, 2.71 and 1.52 hr, 0.6371 and $1.6456 hr^{-1}$, 57.84 and $57.28\;{\mu}g\;{\cdot}\;hr/ml$, 0.1891 and $0.1734 hr^{-l}$, 119.98 and 119.93 mg, respectively. On the basis of experimental results, it was concluded that the bioavailability of brand C rifampicin capsules was almost the same as that of brand F rifampicin capsules.

• Journal of Mechanical Science and Technology
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• 제17권4호
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• pp.581-589
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• 2003

Film absorption involves simultaneous heat and mass transfer in the gas-liquid system. While the non-absorbable gas does not participate directly In the absorption process. its pretence does affect the overall heat and mass transfer. An experimental study was performed to investigate the heat and mass transfer characteristics of LiBr-H$_2$O solution flow ing over 6-row horizontal tubes with the water vapor absorption in the pretence of non-absorbable gases. The volumetric concentration of non-absorbable gas, air, was varied from 0.17 to 10.0%. The combined effects of the solution flow rate and its concentration on the heat and mass transfer coefficients were also examined. The presence of 2％ volumetric concentration of air resulted in a 25% reduction in the Nusselt number and 41% reduction in the Sherwood number Optimum film Reynolds number was found to exist at which the heat and mass transfer reach their maximum value independent of air contents. Reduced Nusselt and Sherwood numbers. defined as the ratio of Nusselt and Sherwood numbers at given non-absorbable gas content to that with pure water vapor, were correlated to account for the reduction in the heat and mass transfer due to non-absorbable gases in a falling film absorption process.