• Korean Journal of Medicinal Crop Science
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• v.5 no.4
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• pp.276-283
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• 1997

This experiment was conducted to investigate the optimum temperature and the effects of sulfuric acid, flowing water and $GA_3$ on the germination of Bupleurum falcatum. At the same time, the effect of germination-related compounds in Bupleurum falcatum seed was tested. Among the tested temperatures $(15,\;20,\;25\;and\;30^{\circ}C)$ the highest germination rate was obtained at $15^{\circ}C$. The optimum soaking time of sulfuric acid was 5 minutes at the concentration of both 0.1 and 1.0%. At the same time, the germination rate was highest when Bupleurum falcatum seed was washed for 2 days in the flowing water before germination test. The effect of $GA_3$ on the germination was highest at 100 ppm out of 10, 50 and 100 ppm. Regardless of treatments, the germination rate of Jeongseon species was higher than that of Mishima species. SEM photographs revealed that most of germination-inhibiting substances in the seed coat were washed away by rinsing in the flowing water for 2 days thus the seed coat became more smooth. The 4, 000 ppm alcohol extract of Bupleurum falcatum seeds inhibited the germination of lettuce seeds as much as 41.7% in Jeongseon species and 58.3% in Mishima species. The higher extract concentration from seed of Bupleurum falcatum, the lower the germination of lettuce seeds was obtained. Out of phenolic acids, the contents of orchinol, pyrogallol, and p-hydroxybenzoic acid were highest in both varieties. Compared with Mishima species, Jeongseon species showed much higher content of salicylic and vanillic acid.

• Journal of Korean Society of Forest Science
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• v.86 no.4
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• pp.443-449
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• 1997

We examined the effect of pretreatments on seed germination, seedling growth, optimal seedling density of Phellodendron amurense. The seeds were carefully purified after collection in late Oct. from natural population at Mt. Chiri. For the evaluation of pretreatment effects, seeds were sowed in an experimental nursery after being stored in open ground($2{\sim}8^{\circ}C$) with soaking in 20% $H_2O_2$, 50-fold pon-pon solution, cold moist stratification in refrigerator($2{\sim}4^{\circ}C$) and dry storage in roam temperature($4{\sim}18^{\circ}C$), respectively, For the effect of growth density of seedlings, seedlings germinated in nursery were precisely controlled with 53, 104, 220, 380 seedlings per $m^2$. Among pretreatments for the promotion of germination rate, pon-pon treatment(68.8%) was highest, the others were higher than that in dry storage(2.3%), and these seed pretreatment methods were significantly different at 1% level. The height growth of seedlings showed the most vigor from Jun.12 to Jul. 8, and from Jul.20 to Aug. 2, and it reached to 72.8% of height growth. In case of 1-0 seedling, although seedling density per $m^2$ was increased, seedling growth was decreased. The optimal seedling density was 104 seedlings per $m^2$. The standard seedlings for plantation were above height 55cm, root collar diameter 8.1mm, and root length 21cm. These results demonstrated that seed of P. amurense requires stratification for the germination promotion.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.1
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• pp.1-12
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• 2010

The aim of this study was to evaluate the preventive effect of commercially available anticariogenic products, specifically, the tooth cream containing Casein phosphopeptide-amorphous calcium phosphate(CPP-ACP), fluoride varnish and low-level fluoride mouthrinse on enamel erosion induced by carbonated beverage in a short period of time. Enamel specimens were treated as follows and were then kept in artificial saliva for 24 hours followed by further processing by alternately soaking them in Cola beverage and in distilled water for 1 minute each five times. Group 1: control group (no treatment) Group 2: tooth cream with CPP-ACP Group 3: fluoride varnish (1,000 ppm F) Group 4: low-level fluoride mouthrinse (227 ppm F) Group 5: fluoride varnish + tooth cream with CPP-ACP Group 6: low-level fluoride mouthrinse + tooth cream with CPP-ACP Microhardness and erosion depth were measured and the mineral loss of each specimen was evaluated by measuring the volumetric fluorescence change(${\Delta}Q$) against the stable fluorescent grid using quantitative light-induced fluorescence(QLF). The experiment lasted for 6 days repeated each day. The results were as follows: 1. The microhardness was increased as follows: Group $1{\leq}2{\leq}4$<6<$3{\fallingdotseq}5$. 2. The mean erosion depth was increased as follows: Group $5{\fallingdotseq}3$<6<$4{\fallingdotseq}2{\fallingdotseq}1$. 3. The ${\Delta}Q$ was increased as follows: Group $1{\fallingdotseq}2{\leq}4{\leq}6{\leq}3{\fallingdotseq}5$. The decrement of ${\Delta}Q$ was similar between group 1 and 2, group 4 and 6 and group 3 and 5. 4. The ${\Delta}Q$ showed positive correlation with microhardness (r=0.96, p<0.05), while it was negatively correlated to erosion depth (r=-0.96, p<0.05).

• Journal of agriculture & life science
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• v.46 no.6
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• pp.117-126
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• 2012

This study carried out on the manufacturing of pidan. The production of pidan can be one of solutions for over-produced eggs and stable egg price. For the alkali-pickling solution for manufacturing of Pidan, the tested concentration of NaOH and NaCl were respectively as 3, 5, 7% and 5, 10, 15, 20%, and examined every 2 days for 14days. According to the results, pH value of alkali-pickling solution was increased by the increment of NaOH concentration and the pickling period, and was decreased by the increment of NaCl concentration. The pH value of egg yolk was increased by the increment of NaOH concentration, but it was not significantly different by the NaCl concentration. By the increment of NaOH and NaCl concentrations, the alkali infiltration in egg yolk and egg white was accelerated. Furthermore, the weight change of the eggs in the alkali-solution has no effects on manufacturing of Pidan. Liquefied albumen showed significant differences by NaOH concentration rather than that of NaCl. There was no liquefied albumen for 14days at 3% of NaOH, but it was found between 11-12days at 5% and 8-10days at 7%, respectively. The pH values of egg white when it was liquefied albumen were between 11.8 and 12.0. Pidan was made by heat treatment after 6-7days dipped in the solution at the concentration of 7%, about 10days at 5%, and 12-14days at 3% of NaOH, respectively. Although, the period of manufacturing of Pidan was saved by the increment of NaOH concentration, liquefied albumen was accelerated and the food preference was decreased by ammonia odor. Therefore, the suitable concentration of NaOH is between 3 and 5%, and that of NaCl is between 5 and 10% due to the effect of salinity by the soaking period. Through this study, optimal pickling solution and dipping time for manufacturing of Pidan was figured out, and also find out that it can save a time about 15days for manufacturing of Pidan.

• Applied Biological Chemistry
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• v.15 no.3
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• pp.213-219
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• 1972

In order to utilize sweet potatoes for the material of Takju, brewing experiments with raw sweet potatoes, sweet potato chips powder and its koji were conducted; and various tests were carried out on effect of the treatments of acid, alkali, polyphenol oxidase inhibitor, oxidizing and reducing agents upon the prevention against coloring of sweet potato chips by steaming, and on peeling effect of sweet potatoes by the alkali and heat treatments. The results obtained were as follows. 1) In the case of brewing with raw sweet potatose, each plot showed low acid and ethanol content, and its finished Takju had an undersirable color and odor. The plots which were mashed after peeling showed higher ethanol contents than the plots mashed without peeling. 2) In the case of brewing with sweet potato chips powder, each plot contained considerably more amount of ethanol than the plots brewed with raw sweet potatoes, white it contained less amount of acid. The ethanol contents of the plots using wheat bran koji were $10.5{\sim}11.4$ per cent 4 days after mashing, and were higher than those of the plots using malts powder. Their finished Takju was inferior in quality because of the lack of acid and being darkened gradually in process of time. 3) The kojies which were made of sweet potato chips powder with Neurospora sitophila or Aspergillus oryzae had good appearance, but the Takju mashes brewed with these contained remarkably less amount of ethanol. 4) Effect of the treatments of acid, alkali, polyphenol oxidase inhibitor and organic solvents such as ether and ethanol upon the prevention against coloring of sweet potato chips was not recognized. Alum and burnt alum were effective a little on the decolorization, and among the oxidizing and reducing agents tested, potassium permanganate was most effective. 5) Darkening of sweet potato chips powder in course of heating after mixing with water was not affected by pectin and amino acids, but by tannin. 6) Sweet potatoes were not peeled easily by friction after soaking in the boiling solution of 3 per cent alkali for 6 minutes and peeled in boiling water for 12 minutes. From the viewpoint of the results above mentioned, it seems to be necessary to study further on the isolation of microorganisms which are able to decompose the coloring substances and yeasts which are adequate for the fermentation of sweet potatoes in order to utilize sweet potatoes for Takju brewing, because brewing with raw sweet potatoes, sweet potato chips powder and its koji was unsuccessful, and effect of the various treatments on the decolorization of sweet potatoes was not recognized.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.1
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• pp.44-50
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• 2016

The purpose of this study was to compare and evaluate the remineralization effect of three types of fluoride varnishes on demineralized enamel of primary teeth. 40 primary teeth were decalcified by soaking them in artificial acidic solution and stored at $37^{\circ}C$ for 7 days. Then 3 varnishes - Cavity shield$^{TM}$, V varnish$^{TM}$ and MI varnish$^{TM}$ were applied respectively one time a week, for 3 weeks on the demineralized enamel surface. For the first week, MI varnish$^{TM}$ showed the highest microhardness value, V varnish$^{TM}$ was in second position, and Cavity shield$^{TM}$ showed the lowest microhardness value. However, there was no significant difference among the three groups(p > 0.05). For the second week, V varnish$^{TM}$ showed the highest microhardness value, and MI varnish$^{TM}$ came next in second position noting no significant difference (p > 0.05). Cavity shield$^{TM}$ was significantly lower than the other groups (p < 0.05). For the third week, V varnish$^{TM}$ showed the highest microhardness value, noting a significant difference from the other groups (p < 0.05). MI varnish$^{TM}$ came next, while Cavity shield$^{TM}$ showed the lowest microhardness value. However, there was no significant difference between MI varnish$^{TM}$ and Cavity shield$^{TM}$ (p > 0.05). The increase in the microhardness of groups V varnish$^{TM}$ and MI varnish$^{TM}$ were higher than that of group Cavity shield$^{TM}$ (p < 0.05), while no significant difference was noted between groups V varnish$^{TM}$ and MI varnish$^{TM}$ (p > 0.05).

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.154-155
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• 2012

The promise of nano-crystalites (nc) as a technological material, for applications including display backplane, and solar cells, may ultimately depend on tailoring their behavior through doping and crystallinity. Impurities can strongly modify electronic and optical properties of bulk and nc semiconductors. Highly doped dopant also effect structural properties (both grain size, crystal fraction) of nc-Si thin film. As discussed in several literatures, P atoms or radicals have the tendency to reside on the surface of nc. The P-radical segregation on the nano-grain surfaces that called self-purification may reduce the possibility of new nucleation because of the five-coordination of P. In addition, the P doping levels of ${\sim}2{\times}10^{21}\;at/cm^3$ is the solubility limitation of P in Si; the solubility of nc thin film should be smaller. Therefore, the non-activated P tends to segregate on the grain boundaries and the surface of nc. These mechanisms could prevent new nucleation on the existing grain surface. Therefore, most researches shown that highly doped nc-thin film by using conventional PECVD deposition system tended to have low crystallinity, where the formation energy of nucleation should be higher than the nc surface in the intrinsic materials. If the deposition technology that can make highly doped and simultaneously highly crystallized nc at low temperature, it can lead processes of next generation flexible devices. Recently, we are developing a novel CVD technology with a neutral particle beam (NPB) source, named as neutral beam assisted CVD (NBaCVD), which controls the energy of incident neutral particles in the range of 1~300eV in order to enhance the atomic activation and crystalline of thin films at low temperatures. During the formation of the nc-/pm-Si thin films by the NBaCVD with various process conditions, NPB energy directly controlled by the reflector bias and effectively increased crystal fraction (~80%) by uniformly distributed nc grains with 3~10 nm size. In the case of phosphorous doped Si thin films, the doping efficiency also increased as increasing the reflector bias (i.e. increasing NPB energy). At 330V of reflector bias, activation energy of the doped nc-Si thin film reduced as low as 0.001 eV. This means dopants are fully occupied as substitutional site, even though the Si thin film has nano-sized grain structure. And activated dopant concentration is recorded as high as up to 1020 #/$cm^3$ at very low process temperature (＜ $80^{\circ}C$) process without any post annealing. Theoretical solubility for the higher dopant concentration in Si thin film for order of 1020 #/$cm^3$ can be done only high temperature process or post annealing over $650^{\circ}C$. In general, as decreasing the grain size, the dopant binding energy increases as ratio of 1 of diameter of grain and the dopant hardly be activated. The highly doped nc-Si thin film by low-temperature NBaCVD process had smaller average grain size under 10 nm (measured by GIWAXS, GISAXS and TEM analysis), but achieved very higher activation of phosphorous dopant; NB energy sufficiently transports its energy to doping and crystallization even though without supplying additional thermal energy. TEM image shows that incubation layer does not formed between nc-Si film and SiO2 under later and highly crystallized nc-Si film is constructed with uniformly distributed nano-grains in polymorphous tissues. The nucleation should be start at the first layer on the SiO2 later, but it hardly growth to be cone-shaped micro-size grains. The nc-grain evenly embedded pm-Si thin film can be formatted by competition of the nucleation and the crystal growing, which depend on the NPB energies. In the evaluation of the light soaking degradation of photoconductivity, while conventional intrinsic and n-type doped a-Si thin films appeared typical degradation of photoconductivity, all of the nc-Si thin films processed by the NBaCVD show only a few % of degradation of it. From FTIR and RAMAN spectra, the energetic hydrogen NB atoms passivate nano-grain boundaries during the NBaCVD process because of the high diffusivity and chemical potential of hydrogen atoms.

• Restorative Dentistry and Endodontics
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• v.33 no.1
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• pp.54-65
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• 2008

The purpose of this study was to determine the effect of sodium hypochlorite and steam autoclaving on the cyclic fatigue of nickel-titanium endodontic files. Two types of files with a .06 taper and #30 were used, $K3^{(R)}$ (SybronEndo, Glendora, California, USA) and Hero $642^{(R)}$(Micro-Mega, BesanCon, France). The files were divided into 6 experimental groups containing 10 files each group depending the soaking time in 6% sodium hypochlorite solution and number of cycles of steam autoclave. After sterilization, a cyclic fatigue test was performed on each file, and the fracture time was recorded in seconds. The control group underwent the cyclic fatigue test only. After the test, the surface characteristics of the files were observed using scanning electron microscopy (SEM). All groups containing the Hero 64~ files showed a similar cyclic fatigue fracture time. However, the cyclic fatigue fracture time with the $K3^{(R)}$ files was significantly shorter in groups which were treated with sodium hypochlorite than in the control group (P < 0.05), SEM revealed both Hero $642^{(R)}$ and $K3^{(R)}$ files to have significant corrosion on the file surface in groups treated with sodium hypochlorite, compared with the sharp and regular blades of the control group. $K3^{(R)}$ files showed more corrosion than the Hero $642^{(R)}$ files. Bluntness of the blades of the $K3^{(R)}$ file was observed in groups treated with steam autoclave. Although there was no obvious destruction on the surface of steam autoclaved Hero $642^{(R)}$ files, slight bluntness was observed. Sterilizing with a steam autoclave is much less destructive to $K3^{(R)}$ files than sodium hypochlorite. The longer time exposed to sodium hypochlorite, the more destructive pattern was shown on the blades of the files. Therefore, when using sodium hypochlorite solution, the exposure time should be as short as possible in order to prevent corrosion and increase the cyclic fatigue fracture time.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.1
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• pp.38-45
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• 2009

The aim of this study was to examine efficacy of the commercially available 10% CPP-ACP cream (Tooth mousse, GC Co., Japan) and/or 0.05% NaF solution on the remineralization of artifical caries-like lesion in the bovine teeth enamel. Sixty bovine teeth were embedded in orthodontic resin and flattened. The enamel surface in 3 mm diameter was exposed with nail varnish. Specimens were stored in demineralizing solution and divided 5 groups; Group 1 (No treatment), 2 (0.05% NaF solution 1 min), 3 (Tooth mousse 3 min), 4 (After 0.05% NaF solution, Tooth mousse treatment), and 5 (After Tooth mousse treatment, soaking in 0.05% NaF solution during 1 min). After treatment by groups, all specimens was stored in artificial saliva for 30 min. After the process described as above was performed during 10 days without pH cycling, surface hardness (Vickers Hardness Number, VHN) was tested and analyzed by paired t-test and one-way ANOVA test with SPSS 14.0. In intragroup comparison between surface hardness of pre and post-treatment, group 3, 4, 5 showed statistically significant increase (P < 0.05). In intergroup comparison among surface hardness increase of all groups, difference of group 5 between pre and post-treatment ($15.80{\pm}12.21$) was the highest, and followed by group 4 ($14.27{\pm}11.73$), 3 ($4.05{\pm}5.18$), 2 ($1.15{\pm}6.83$), 1 ($0.78{\pm}6.21$). Tooth mousse can be a good alternative agent for the fluoride, and the combination use with fluoride might have the additional anticariogenic effect.

• Journal of Mushroom
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• v.7 no.4
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• pp.173-181
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• 2009

These studies were investigated for effect of concentration of sodium chloride on occurrence and growth of fruitbody in oyster mushroom, Pleurotus ostreatus. When the mycelia were inoculated and cultured on the PDA plate added with the different concentrations of sodium chloride, the growth of them were not affected at the concentration of 0.5%, started to decrease at 1.0% as compared with the PDA plate without sodium chloride, and they did not grow at 5.0%. When tested at the column filled with sawdust, the tendency was similar, but the decreasing rate of mycelial growth was gentle. In sawdust bottle cultivation sprinkled with the different concentration of sodium chloride solution at the different stage, the productivity and quality of fruitbody started to decrease at 3.0% of the solution and the yield at the treatment of 10.0% solution was only 47% of that in non-treated bottles. Treated at the different stages of mushroom development, treatment just after mushroom sprout did not show any different from that just after scraping spawn from the complete grown bottles. The sprinkle treatment at this stage looked better than that of the soaking with the solution before mushroom sprout. The yield at this treatment with 10% solution showed little damage with that of 90% of non-treated bottle. Sprinkle treatment during mushroom growth stage did not affect and showed almost same to non-treated bottle except the treatment with 10.0% solution. The treatment of this stage showed better results of growing characters than the treatment after and before mushroom sprouting even 10% solution. Morphological characteristics of oyster mushroom do not distinguish to treatment of different stage and concentration of sodium chloride solution. The analyzing data of quality on underwater usually used for oyster mushroom in Inchon, Yeongjong and Kanghwa area showed over-concentration to the standard for edible water and agricultural water. But it was not confirmed whether this water quality could affect to mushroom cultivation.