• Journal of the Korean Magnetics Society
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• v.15 no.2
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• pp.100-105
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• 2005

$Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticles have been prepared by a sol-gel method. The structural and magnetic properties have been investigated by DTA/TGA, XRD, SEM, and $M\ddot{o}ssbauer$ spectroscopy, VSM. $Ni_{0.9}Zn_{0.1}Fe_2O_4$ powder that was annealed at $300^{\circ}C$ has spinel structure and behaved superparamagnetically. The estimated size of superparammagnetic Ni-Zn ferrite nanoparticle is around 10 nm. The hyperfine fields at 13 K for the A and B patterns were found to be 533 and 507 kOe, respectively. The blocking temperature ($T_B$) of superparammagnetic $Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticle is about 250 K. The magnetic anisotropy constant and relaxation time constant of $Ni_{0.9}Zn_{0.1}Fe_2O_4$ nanoparticle were calculated to be $1.6\times10^6\;ergs/cm^3$ and ${\tau}_0=5.0{\times}10^{-13}$ s, respectively. Also, Temperature increased up to $43^{\circ}C$ within 10 minutes under AC magnetic field of 7 MHz. It is considered that $Ni_{0.9}Zn_{0.1}Fe_2O_4$ powder that was annealed at $300^{\circ}C$ is available for biomedicine application such as hyperthermia, drug delivery system and contrast agents in MRI.

• Journal of the Korean Wood Science and Technology
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• v.35 no.1
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• pp.73-80
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• 2007

This study was carried out to separate the heavy toxic metals in eco-building materials by low-temperature pyrolysis, especially arsenic (As) compounds in CCA wood preservative as a solid in char. The pyrolysis was carried out to heat the CCA-treated Hemlock at $280^{\circ}C$, $300^{\circ}C$, $320^{\circ}C$, and $340^{\circ}C$ for 60 mins. Laboratory scale pyrolyzer composed of [preheater$\rightarrow$pyrolyzer$\rightarrow$1st water scrubber$\rightarrow$2nd bubbling flask with 1% $HNO_3$ solution$\rightarrow$vent], and was operated to absorb the volatile metal compound particulates at the primary water scrubber and the secondary nitric acid bubbling flask with cooling condenser of $4^{\circ}C$ under nitrogen stream of 20 mL/min flow rate. And the contents of copper, chromium and arsenic compounds in its pyrolysis such as carbonized CCA treated wood, 1st washing and 2nd washing liquors as well as its raw materials, were determined using ICP-AES. The results are as follows : 1. The yield of char in low-temperature pyrolysis reached about 50 percentage similar to the result of common pyrolytic process. 2. The higher the pyrolytic temperature was, the more the volatiles of CCA, and in particular, the arsenic compounds were to be further more volatile above $320^{\circ}C$, even though the more repetitive and sequential monitorings were necessary. 3. More than 85 percentage of CCA in CCA-treated wood was left in char in such low-temperature pyrolytic condition at $300^{\circ}C$. 4. Washing system for absorption of volatile CCA in this experiment required much more contacting time between volatile gases and water to prevent the loss of CCA compounds, especially the loss of arsenic compound. 5. Therefore, more complete recovery of CCA components in CCA-treated wood required the lower temperature than $320^{\circ}C$, and the longer contacting time of volatile gases and water needed the special washing and recovery system to separate the toxic and volatile arsenic compounds in vent gases.

• Korean Journal of Poultry Science
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• v.18 no.3
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• pp.183-196
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• 1991

In order to establish ELISA method to detect antibody against IBV various factors involved were examined. Antigen was prepared from Massachusetts type IBV which is known to be one of serotypes distributed most widely. The virus was grown in embryonated SPF chicken eggs. Allantoic fluid harvested was processed to ultracentrifugation and sucrose density gradient centrifugation to produce a purified antigen The antisera selected from the field samples based on hemagglutination inhibition test were used as the standard positive and negative sera for this study and the results obtained were summarized as follows. 1 , It was found that ELISA test was satisfactory when the purified antigen was coated on the plate in the amount of about 40ng protein per well. In case of the phospholipase treated hemagglutinating antigen it gave satisfactory results when the each well wns coated with 1.2 to 2.5 hemagglutinating unit which was equivalent to 40 to 90ng of protein. 2. There was no significant difference in the ratio of optical density of positive to that of negative serum whether the coated antigen was held for 1 hour at 37$^{\circ}C$ or it was held overnight at 4$^{\circ}C$. The coated antigen could be kept in dried state without change of antigenecity for at least one month of experimental period at 4$^{\circ}C$. 3. There was a big variation in the optical density and P/N values depending on the maker of the plates and on the plate of the same maker. 4. It was found that background optical density was negligible when serum was diluted more than 1：50 and serum dilution of 1：100 appeared to be appropriate as a routine test dilution to screen the antibody. 5. Optical density was fairly constant 15 minutes afterward from the time substrate was treated and during the 4 hours after stopper was treated. 6. There was a low correlation(r＝0.42) between ELISA and HI test. However, when 74serum samples were tested for the IBV antibody, 98.7% were found to be positive by both tests in which titers of 2$^{6}$ or more by HI test and P/N values of 1.4 or more by ELISA were considered to be positive, 7 Day-old IBV vaccinated chickens shows a similar antibody decay and rising pattern until 8 weeks of age by the two tests, ELISA and HI.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.1
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• pp.67-74
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• 2023

In this study, for a natural cosmetics market, we sought to explore alternatives that can replace polyvinyl alcohol (PVA) of peel-off packs. A peel-off type pack was prepared by combining pullulan, a water-soluble polysaccharide, and other polysaccharides (sodium hyaluronate, cellulose gum, hydroxyethyl cellulose, sodium alginate, corn starch), and the pH, viscosity, and stability against temperature of each peel-off type pack were confirmed. The thickness and tensile strength of the manufactured film were measured for comparison with the PVA peel-off type pack, and applicability, drying speed, and removal degree were measured. Among them, the pullulan-sodium hyaluronate peel-off type pack showed excellent film formation ability to replace the peel-off type pack containing PVA with 5.12% thin film thickness and 4.23% high film tensile strength. When applied to actual skin, the degree of spread of the pack, the usability that can be uniformly applied, and the formation and removal strength of the film when removed after drying were also similar to the peel-off type pack containing PVA. Therefore, it was confirmed that the film formed of pullulan-sodium hyaluronate showed enough physical properties to replace the PVA of the peel-off type pack as a natural peel-off type pack.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.11
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• pp.1116-1122
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• 2008

The existing technology which is for recycling aggregate using dried swage sludge have been limited for practical application, because the properties of aggregate are not regular and don't meet the recycling aggregate standard. In this research, an innovative slag-producing technology is developed by addition of oyster shell, waste cast-sand and iron-rust as inorganic waste additives. The mixed slag with the additives was evaluated at the various ratio of CaO/SiO$_2$, SiO$_2$/Al$_2$O$_3$ and Fe$_2$O$_3$/SiO$_2$. When the waste sludge was melted at 1,400$^{\circ}C$ during 20 minutes, the optimal ratio of CaO/SiO$_2$ for the slag added the oyster shell, SiO$_2$/Al$_2$O$_3$ for added the waste cast-sand and Fe$_2$O$_3$/SiO$_2$ for added the iron-rust were 1.00, 3.00 and 0.60, respectively. At the optimal condition, the bulk density of the slag was 2.24 g/cm$^3$, 2.45 g/cm$^3$ and 2.73 g/cm$^3$, And the 24 h water adsorption was 4.72%, 1.44% and 0.37%, respectively. Therefore it is proved that adding the waste additives to the process of the slag production contributed for elevation of recycling aggregate properties. And also it is expected that production cost can be reduced by decreased melting temperature.

• Journal of Animal Science and Technology
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• v.49 no.6
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• pp.745-752
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• 2007

A total of thirty sows(Landrace×Yorkshire) were used to determine the effects of plant protein source containing multienzyme on performance, nutrients digestibility and milk characteristics. A feeding trial was conducted for 21 days from parturition to weaning. Experimental diets were supplied for 1 week before the parturition day and throughout the experimental period. Dietary treatments included: 1) Control(CON; basal diet), 2) CGLT(included corn gluten) and 3) FSPM(included fermented soy protein containing multienzyme). Through the entire experimental period, backfat loss and return-to-estrus intervals were not affected by the treatments(P>0.05). Nitrogen digestibility was increased significantly(P<0.05) in FSPM treatment compared to CON treatment. Blood urea nitrogen(BUN) concentration was increased significantly (P<0.05) in FSPM treatment compared to CON treatment. At the initial  period, total protein content of milk was higher significantly(P<0.05) in FSPM treatment compared to CGLT treatment and at the final period, total fat content of milk was higher significantly(P<0.05) in FM treatment compared to CON treatment. Rectal temperature showed similar tendency of change among treatments. The final piglet body weight, weight gain and ADG were higher significantly in FSPM treatment compared to CON treatment. On diarrhea rate in piglet, just one piglet occurred in CGLT treatement. In conclusion, 2.5% dietary plant protein source containing multienzyme suppelmentation improved N digestibility, BUN concentration, fat and protein contents in milk and weight gain in piglet.

• Journal of Animal Science and Technology
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• v.49 no.6
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• pp.773-782
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• 2007

A total of thirty sows(Landrace×Yorkshire) were used to determine the effects of plant protein source containing multienzyme on performance, nutrients digestibility and milk characteristics. A feeding trial was conducted for 21 days from parturition to weaning. Experimental diets were supplied for 1 week before the parturition day and throughout the experimental period. Dietary treatments included: 1) Control(CON; basal diet), 2) CGLT(included corn gluten) and 3) FSPM(included fermented soy protein containing multienzyme). Through the entire experimental period, backfat loss and return-to-estrus intervals were not affected by the treatments(P>0.05). Nitrogen digestibility was increased significantly(P<0.05) in FSPM treatment compared to CON treatment. Blood urea nitrogen(BUN) concentration was increased significantly (P<0.05) in FSPM treatment compared to CON treatment. At the initial  period, total protein content of milk was higher significantly(P<0.05) in FSPM treatment compared to CGLT treatment and at the final period, total fat content of milk was higher significantly(P<0.05) in FM treatment compared to CON treatment. Rectal temperature showed similar tendency of change among treatments. The final piglet body weight, weight gain and ADG were higher significantly in FSPM treatment compared to CON treatment. On diarrhea rate in piglet, just one piglet occurred in CGLT treatement. In conclusion, 2.5% dietary plant protein source containing multienzyme suppelmentation improved N digestibility, BUN concentration, fat and protein contents in milk and weight gain in piglet.

• Korean Journal of Materials Research
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• v.5 no.6
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• pp.754-762
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• 1995

Strontium titanate(SrTiO$_3$) thin film was prepared on Si substrates by RF magnetron sputtering for a high capacitance density required for the next generation of LSTs. The optimum deposition conditions for SrTiO$_3$thin film were investigated by controlling the deposition parameters. The crystallinity of films and the interface reactions between SrTO$_3$film and Si substrate were characterized by XRD and AES respectively. High quality films were obtained by using the mixed gas of Ar and $O_2$for sputtering. The films were deposited at various bias voltages to obtain the optimum conditions for a high quality file. The best crystallinity was obtained at film thickness of 300nm with the sputtering gas of Ar+20% $O_2$and the bias voltage of 100V. The barrier layer of Pt(100nm)/Ti(50nm) was very effective in avoiding the formation of SiO$_2$layer at the interface between SrTiO$_3$film and Si substrate. The capacitor with Au/SrTiO$_3$/Pt/Ti/SiO$_2$/Si structure was prepared to measure the electric and the dielectric properties. The highest capacitance and the lowest leakage current density were obtained by annealing at $600^{\circ}C$ for 2hrs. The typical specific capacitance was 6.4fF/$\textrm{cm}^2$, the relative dielectric constant was 217, and the leakage current density was about 2.0$\times$10$^{-8}$ A/$\textrm{cm}^2$ at the SrTiO$_3$film with the thickness of 300nm.

• Journal of the Korean Vacuum Society
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• v.14 no.2
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• pp.78-83
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• 2005

Nanometric crystalline silicon (no-Si) embedded in dielectric medium has been paid attention as an efficient light emitting center for more than a decade. In nc-Si, excitonic electron-hole pairs are considered to attribute to radiative recombination. However the surface defects surrounding no-Si is one of non-radiative decay paths competing with the radiative band edge transition, ultimately which makes the emission efficiency of no-Si very poor. In order to passivate those defects - dangling bonds in the $Si:SiO_2$ interface, hydrogen is usually utilized. The luminescence yield from no-Si is dramatically enhanced by defect termination. However due to relatively high mobility of hydrogen in a matrix, hydrogen-terminated no-Si may no longer sustain the enhancement effect on subsequent thermal processes. Therefore instead of easily reversible hydrogen, phosphorus was introduced by ion implantation, expecting to have the same enhancement effect and to be more resistive against succeeding thermal treatments. Samples were Prepared by 400 keV Si implantation with doses of $1\times10^{17}\;Si/cm^2$ and by multi-energy Phosphorus implantation to make relatively uniform phosphorus concentration in the region where implanted Si ions are distributed. Crystalline silicon was precipitated by annealing at $1,100^{\circ}C$ for 2 hours in Ar environment and subsequent annealing were performed for an hour in Ar at a few temperature stages up to $1,000^{\circ}C$ to show improved thermal resistance. Experimental data such as enhancement effect of PL yield, decay time, peak shift for the phosphorus implanted nc-Si are shown, and the possible mechanisms are discussed as well.

• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.98-108
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• 1974

Fourteen varieties of Korean chestnut were subjected to the test of adaptability for processing and the possibilities of colored products development. The fruit size of Korean chestnut ranged $11{\sim}18g$ and these small fruits could not be expected to be utilized for the processing of Marron glaces which requires larger size as $25{\sim}30g$. As the storge period is extended the discoloration tendency of chestnut flesh was increasingly developed, however, the fresh chestnut has shown layer-separating phenomenon and ragged surface of fruit which delivers disagreeable appearance to the finished product. The principal factors of discoloration occurred during processing were the behavior of tannin and darkening rate shown on flesh differed each other among varieties; the Chukpa and Yuma variety have exhibited the most serious discoloration and the Taab-b variety, the lightest. Taab-b variety in this connection could be expected to be available for Kanroni processing. For the industrialization of chestnut processing the flame-scorched peeling method is advisable. The capacity of this method is proportional to the square of scorching radius and highly flexible in controlling its performance. As for the processing of colored product, the sugar dehydration and coating and the sugar penetration method demand further study in basical views; however, the canned product of chestnut-redbean has shown the possibility of being utilized as a substitute for or paralleled use with the sugar-syruped canned product which so far has been considered as the only item of export to Japan.