• Journal of the Korean Ceramic Society
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• v.33 no.8
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• pp.849-854
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• 1996

boehmite which is the by-product in alcohol process contains anions such as $Cl^-,{NO_3}^-.or\; CH_3COO^-$ Influe-nce of these anions was studied on properties of $\alpha$-alumina powders prepared by treating the transformed ${\gamma}$-alumina with the alumina sol and $\alpha$-alumina seeds (d_{50}=0.36\mu\textrm{m}$) Disperal 20/1 and 10/1 containing $Cl^-$ produced spherical powder Disperal 20/2 with ${NO_3}^-$ produced equiaxed powder and Disperal 10/3 with $CH_3$ $COO^-$ irregular shaped and sized powder. All of these $\alpha$-alumina powders were submicron. Although the green density of the alumina powder derived from Disperal 10/1 by calcination at $1200^{\circ}C$/1h. was 53% it did not sinter even at $1550^{\circ}C$ for 2h. which implies that its d50 is greater than $3\mu\textrm{m}$. The others gave green densities in the range of 44~47% but they sintered as well as the AKP-30 at $1500^{\circ}C$/2 h or $1550^{\circ}C$/2 h.

• Journal of the Korean Ceramic Society
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• v.28 no.11
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• pp.851-858
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• 1991

Spherical fine BaTiO3 powders with an average diameter of 0.3${\mu}{\textrm}{m}$ to 0.9${\mu}{\textrm}{m}$ are prepared at 100$0^{\circ}C$ by the ultrasonic spray pyrolysis of solutions containing Ba(NO3)2 and TiCl4. Experimental variables are adjusted to produce BaTiO3 powders and its effect on the phase, the size and the morphology of the particles are investigated by XRD, SEM, TEM. Each particle consists of small primary particles and has a hollow around its center. The dependence of particle diameters on the concentrations of source solutions indicates that metal salt precursors are dried to precipitate solid particles and decompose to form BaTiO3 phase without gas phase reactions.

• Korean Journal of Environmental Biology
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• v.18 no.2
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• pp.269-277
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• 2000

When Persicaria thunbergii and Rumex crispus were treated with Cd($NO_3$)$_2$ and Pb($NO_3$)$_2$ of 5 or 10 mM for 5 days, the amount of bioaccumulation of $Pb^{2+}$ in the leaf of P. thunbergii was 2.87-8.08$\mu\textrm{g}$/g and that of $Cd^{2+}$ was 0.82-2.79$\mu\textrm{g}$/g. In the case of P. thunbergii, the concentration of $Pb^{2+}$ in the leaf was higher than that of $Cd^{2+}$. On the other hand, in R. crispus, the concentration of $Cd^{2+}$ and $Pb^{2+}$ were similar as follows ; 1.49$\mu\textrm{g}$/g in $Cd^{2+}$ 5mM, 2.90$\mu\textrm{g}$/g in Cd2+ 10mM, 1.83$\mu\textrm{g}$/g in $Pb^{2+}$ 5mM and 2.73$\mu\textrm{g}$/g in $Pb^{2+}$ 10mM. The remaining rate of heavy metals and the variation of pH in the cultured soil decreased as compared with control (100 % and pH 6.48) after 5 days as follows; to 77.l% and pH 6.39 in $Cd^{2+}$ 5mM, 90.2% and pH 5.79 in $Cd^{2+}$ 10 mM, 81.1% and pH 6.00 in $Pb^{2+}$ 5mM, and 85.7% and pH 5.80 in $Pb^{2+}$ 10 mM. The result of size exclusion chromatography, several phytochelatins were seperated from the extract of the leaf of both plants treated with heavy metals. The molecular mass of these phytochelatins were estimated as follows; in the case of P. thunbergii, about 4,300-8,600 da by $Cd^{2+}$ and about 3,200-9,700 da by $Pb^{2+}$, and in R. crispus, about 4,300 da by $Cd^{2+}$ and about 3,200-7,500 da by $Pb^{2+}$. In addition, $A_{254}$ of these phytochelatins were higher than $A_{280}$. [Phytochelatin, Persicaria thunbergii, Rumex crispus]

• Korean Journal of Animal Reproduction
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• v.10 no.2
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• pp.211-217
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• 1986

This experiment was conducted to determine the effect of FSH on in vitro maturation and in vitro fertilizing ability of oocytes recovered from normal follicles of different sizes in superovulated rabbits. Follicular oocytes recovered were cultured in modified Ham's F12 medium containing 0, 0.1, 1.0 and 10$\mu\textrm{g}$ FSH/ml for 18 hours and investigated the degree of cumulus cells expansion and nuclear maturation, which were fertilized with in vivo capacitated rabbit sperm. 1. The number of normal follicles<1.5mm, 1.6 to 2.5mm and> 2.5mm in diameter at 16 to 18hrs after HCG administration was 4.8 (38.8%), 5.5(45.4%) and 3.3(15.8%), respectively. Average percent of oocytes recovered was 69.7% and larger follicles tended to have a higher percent, recovery rate than smaller follicles. 2. The degree of cumulus expansion in medium containing 0.1$\mu\textrm{g}$ FSH/ml was similar to that of control, but markedly decreased under the level of above 1$\mu\textrm{g}$ FSH/ml. The proportions of oocytes which reached the second meiotic metaphase were 57.1, 61.5, 43.8 and 45.0% in medium containing 0, 0.1, 1.0 and 10$\mu\textrm{g}$ FSH/ml, respectively. Oocytes from larger follicles showed a higher nuclear maturation than that from smaller follicles. 3. In vitro fertilization rate of oocytes matured under 1$\mu\textrm{g}$ FSH/ml was slightly, not significant, higher than that of others. 4. Progesterone level in follicular fluid was about 67 to 71ng/ml with no difference in follicular sizes and estradiol-17$\beta$ level was under 25pg/ml.

• Biomolecules & Therapeutics
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• v.2 no.3
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• pp.270-280
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• 1994

This study was conducted to evaluate the repeated dose toxicity of DA-3030, a recombinant human granulocyte colony stimulating factor(rhG-CSF), in rats. DA-3030 was administered intravenously once a day for 4 weeks to 20 males and 20 females per group at doses of 0(control), 115 and 1150 $\mu\textrm{g}$/kg, and to 15 males and 15 females per group at doses of 1.15 and 11.5$\mu\textrm{g}$/kg. After the administration period, 5 males and 5 females per group in the 0,115 and 1150 $\mu\textrm{g}$/kg groups were placed on withdrawal for 2 weeks. Through-out the study, all the rats survived. The administration of DA-3030 induced, a marked increase in the number of peripheral neutrophils, elevation of serum alkaline phosphatase activity, and splenomegaly in the rats of both sexes receiving 115 or 1150 $\mu\textrm{g}$/kg. Histopathologic examination revealed extramedullary granulopoiesis in spleen and liver, and increase in the number of activated macrophages in spleen in rats of both sexes in 115 and 115 $\mu\textrm{g}$/kg groups, and increased M/E ratio in 11.5, 115 and 1150$\mu\textrm{g}$/kg groups. Most of the changes produced by DA-3030 were thought to be attributable to exaggerated pharmacological effect of the drug, and subsided or disappeared after the recovery period. Under the present condition, no effect dose of DA-3030 is estimated at 1.15 $\mu\textrm{g}$/kg/day.

• Journal of Veterinary Clinics
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• v.16 no.1
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• pp.57-64
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• 1999

It was performed to evaulate the effects of occlusion of mandibular gland and sublingual gland on the mandibular gland in dogs. The occlusion of mandibular gland and sublingual gland was induced by ligature in clinically normal dogs, and ultrasonograpic appearance, hematological changes and histological changes of the mandibular gland were observed daily during 6 days. The results were as follows. 1. The length, width, circumference and area of the mandibular gland in clinically normal dogs were 25.1 mm, 8.4 mm, 56.4 mm and 163.0 $\textrm{mm}^2$ in the left, and 23.4 mm, 8.0 mm, 53.3 mm and 141.6 $\textrm{mm}^2$in the right. 2. The length, width, circumference and area of the mandibular gland were gradually increased after ligature of the salivary duct, and revealed maximum values, as 33.4 mm, 10.9 mm, 73.0 mm and 287.2 $\textrm{mm}^2$, respectively, at 24 hours after ligature, and returned to normal size at 3 days after ligature. 3. The size of the opposite mandibular gland without ligature was also gradually increased until 24 hours, and returned to normal size at 3 days, similar to the changes of the mandibular gland with ligature. 4. There were no significant changes after ligature of the salivary duct in hematological findings. 5. In histopathological findings, the major of glandular alveoli was enlarged at 24 hours after ligature of the salivary duct, and neutrophils and monocytes were infiltrated at 6 days after ligature.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.2
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• pp.137-145
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• 1994

A visibility analysis model based on the Mie theory is applied to the measurements during the fall, 1993 in Seoul. Model estimations of the total extinction coefficient $b_{ext}$, and the particle scattering coefficient, $b_{sp}$ are in good agreement with the measured values by a transmissometer and a nephelometer, respectively. These values show strong dependency on the mass loading of fine particles( $D_{p}$ ＜3.0${\mu}{\textrm}{m}$) but show no apparent relation with that of coarse particles(3.0${\mu}{\textrm}{m}$＜ $D^{p}$ ＜10${\mu}{\textrm}{m}$). Relative humidity plays an important role in determining the size of particles which in turn, affects the optical efficiency of aerosol. Based on the composition analysis with cut size nitrate concentration is higher than the sulfate concentration in PM3-10 but they are comparable to each other in PM3. Considering in 1985, it demonstrates a drastic increase of nitrate concentration between 1985 and 1993. It is found that measured and estimated light extinction budget were in good agreement within 10% and that scattering by particles is responsible for about 50-55% and 70-80 % of total extinction during clear and smoggy periods respectively.y.

• Journal of Bio-Environment Control
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• v.5 no.1
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• pp.89-97
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• 1996

Oriental melon and watermelon plants were cultivated in the soil treated with bioceramics in a greenhouse during summer season from June 1st to August 20th, 1995. Two application methods were employed, one was a mixed treatment of soil and bioceramics, and the other was a spray treatment of bioceramic solution on the stems and leaves. And two types of bioceramics were also stopped by five levels. In order to analyze the bioceramic effect on oriental melon and watermelon, the growth rate of stems, leaves and fruits were measured in the greenhouse. After harvest, the sweetness of fruits was measured and the freshness of fruits based on the storage period was tested by human taste and smell sense. The results are summarized as follows. 1. The growth rates of stems, leaves and fruits of oriental melon and watermelon were the largest in the bioceramic treatment of No. 3. 2. The density of oriental melon and watermelon was the largest in the bioceramic treatment of No. 3 and No. 2 respectively. 3. The Brix number of watermelon was 10.6 in non-bioceramic treatment and 11.5 in the bioceramic treatment of No. 2, and that of oriental melon was 8.6 in non-bioceramic treatment and 12.3 in the bioceramic treatment of No. 2. 4. The storage duration of watermelon treated with bioceramics was about 50 days in the condition of the ambient temperature of 25-3$0^{\circ}C$.

• Korean Journal of Veterinary Service
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• v.21 no.2
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• pp.157-161
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• 1998

To get the information of sanitary develoment of beef and pork, we get the result of environmental specimens(slaughter house floors, sewage, etc) in laboratory. 1. After examination of bacterial infection on after-bleeding, after-dismemberment and final products at each stage of cattle slaughter process, we got log 3.80~7.48cfu/$\textrm{cm}^2$ of aerobic plate counts and log 2.60~5.23cfu/$\textrm{cm}^2$ of coliform counts or so from the carcasses after bleeding, but these count levels went down little bit after dismemberment but as we continued study to the final products, the count levels kept sililar in mumbers. 2. At the slaughter process of pigs, the aerobic plate counts and the coliform counts reached such high levels of log 5.59~8.80cfu/$\textrm{cm}^2$ and log 3.31~5.67cfu/$\textrm{cm}^2$, respectively, after bleeding, in general, these count diminished in a big way after scalding, but they increased just little bit from dismemberment to final products. And there were few differences in the contamination levels on the final products no matter what seasonal contaminations after bleeding. 3. Test revealed very low levels of cell counts both on the aerobic plate counts of washing water and in the coliform counts, the former was log 1.00~2.69cfu/$\textrm{cm}^2$ and the later was log 3.30~5.67cfu/$\textrm{cm}^2$, but the contamination levels on the beds of transfering vehicles for carcasses were very high as followes : the aerobic counts was log 4.23~7.20cfu/$\textrm{cm}^2$ and coliform counts was log 2.86~5.20cfu/$\textrm{cm}^2$. 4. Study showed the aeroboc plate counts and the coliform counts get to the highest levels in summer, the second highest one is in fall, the third in spring, lowest in winter. Resulting from the test results proven above we reached this kind of conclusion the bacterial contaminations on eatable carcasses were upto hygienic treatment of carcasses and cleaniness of transfering vehicles at the final stop of slaughter processes rather than upto at any stage of slaughter processes. Therefore we have got to establish alternatives immediately to develo sanitary quality of meat and pork.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.600-607
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• 1996

Colored rices have been used for specific purposes by rice consumers due to the color and nutritive values empirically recognized. In this study, varietal variations of pigmentation and nutritive values were investigated in brown, red, purple and black rices. Pigments were localized in seed coat to pericarp region in all varieties tested. Pigments were slightly residued on the surface of milled rice. Anthocyanin content per g brown rice was 1.63~17.62 $\mu\textrm{g}$ in brown and reddish-brown rices, 3.56~11.10 $\mu\textrm{g}$ in red rices, 28.11~401.22 $\mu\textrm{g}$ in purple rices, and 3, 665.98 $\mu\textrm{g}$ in a black rice. A vatiety DZ 78 showed the highest protein content out of colored rices analyzed for protein. Normal and colored rices were found to have the similiar composition of amino acids, and so was in between brown rice without embryo and milled rice. Colored rices, L $K_1$B-4-12-1-1 and DK 1, showed higher content of vitamin $B_1$ compared with Hwacheongbyeo, a check variety of no specific color, and L $K_1$B-2-1-1 and L $K_1$B-4-12-1-1 showed much higher content of vitamin B2 in brown rice without embryo. Cation contents such as $K^{+}$, $Mg^{2+}$, $Ca^{2+}$ and F $e^{2+}$ were significantly increased in most of the colored rices tested implying that the increase might be associated with color pigmentation.ation.