• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.631-639
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• 2011

This research was conducted to investigate potential use of New Zealand spinach (Tetragonia tetragonoides) as a new vegetable crop which will be cultivating in salt-affected soils including reclaimed land. Traditionally New Zealand spinach has been studied to explore functional compound or salt removing potential. To cultivate the crop species in the salt-affected soil widely, it is essential to obtain salt and soil texture responses under the controlled environment. Fifty nine New Zealand spinach ecotypes native to Korean peninsula first collected over seashore areas, and primitive habitat soil environment was evaluated by analyzing soil chemical properties from 32 locations. Different textures of sandy, silt loam, and sandy loam soils were prepared from nearby sources of sea shore, upland and paddy soils, respectively. Target salinity levels of 16.0 dS/m, 27.5 dS/m, 39.9 dS/m, and 52.4 dS/m in electrical conductivity (ECw) were achieved by diluting of 25, 50, 75, 100% (v/v) sea water to tap water (control, 0.6 dS/m), respectively. Various measurements responding to soil texture and irrigation salinity included plant height, root length, fresh weight (FW), dry weight (DW), leaf parameters (leaf number, leaf length, leaf width), lateral branching, and inorganic ion content. was found to adapt to diverse habitats ranging various soil chemical properties including soil pH, organic matter, exchangeable bases, EC, and cation exchange capacity (CEC) in Korea. Responding to soil texture, New Zealand spinach grew better in silt loam and sandy loam soil than in sandy soil. Higher yield (FW and DW) seemed to be associated with branch number (r=0.99 and 0.99, respectively), followed by plant height (r=0.94 and 0.97, respectively) and leaf number (r=0.89 and 0.84, respectively). Plant height, FW, and DW of the New Zealand spinach accessions were decreased with increasing irrigation salinity, while root length was not significantly different compared to control. Based on previous report, more narrow spectrum of salinity range (up to 16 dS/m) needs to be further studied in order to obtain more accurate salinity responses of the plant. As expected, leaf Na content was increased significantly with increasing salinity, while K and Ca contents decreased. Growth responses to soil texture and irrigation salinity implied the potential use of New Zealand spinach as a leafy vegetable in salt-affected soil constructed with silt loam or sandy loam soils.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.1
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• pp.73-82
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• 2017

In Korea, previous certification of water supply infrastructure was mainly focused on economical and physical aspects. Recently, hygienic safety of water supply service has become a sensitive and important issue to our people for evaluating the water quality with growth of economy and education system. According on water quality in 497 Korean water supply facilities, pH values in the supplied water have ranged between 5.8-8.5. However, little is known about metal leachability at the pH conditions observed in the real water supply systems because a fixed pH condition (pH 7.0) has been used in the current standard method, 'Hygienic Safety Testing Method', in water supply. In this work, we examined the effects on heavy metal leachability with pH differences in the water supply pipes which are typically used in Korea. As a result, the amounts of metal leachability were tended to increase when pH levels were decreased. Especially at pH 5.8, Cu leachability from Cu pipes was found to exceed the public health standard level even after applying a normalization factor (NF) given by the current Korea standard method. The Cr and Cu leached from stainless steel pipes, Cd, Pb, Cu, and Zn from Cu-based pipe fittings, and Zn from Zn-based pipe fittings were exceeded the Korean hygienic safety standards while, after applying the NF, concentrations of the leached metals were satisfied with the current Korean standard. The findings from this work provide implications on the needs of reforming the current hygienic safety standard methodology.

• Journal of Ginseng Research
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• v.20 no.3
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• pp.291-298
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• 1996

Free amino acid (FAA) compositions in the central part (pith-xylem : P-X) and the outer part (phloem-cortex : P-C) of root were investigated for P ginseng (P.g), p. quinque-folium (P.q) an, B P nutoginsen (P.n) by an amino acid analyzer. Total free amlno acids content (TFAA) was highest in p.맥 and lowest in p.n. The TFAA of P-Xs were higher than those of P-Cs in these Panax species except p.n. The higher the TFAA in P-X, the higher the ratio of TFAA in P-X to that in P-C. Seven- teen free amino acids and ammonia were identified, and four unknown peaks appeared before the usual amino acids eluted. The total aspartic acid equivalent of these unknown peaks was corresponded to 77% of known TFAA in P-C of p.n, 17% in P. n, and 7% in p.q. The pattern of unknown peaks of p.g was different from p.q and similar to P.n. In all samples six major amino acids and ammonia accounted for 90~95% of TFAA. Arginine was comprised from 29% (P.n) to 43% (P.g) by amole as amino acid and from 50 to 71% by amole as nitrogen (N amole) in TFAA. Ammonia was the second abundant one by amole and the third by Npmole. Histidine was the second by Npmole. Praline was one of major FAA in p.q. Pattern similarity of FAA composition (excluding Arg and Am) by simple correlation was closer between P-C of p.g and P-X of p.q than between both P-Xs and quite different between the P-X of p.g and that of p.n. The pattern similarities of major FAA percent abundance excluding Arg and Am were significant only between P-X and P-C of the same species. Arginine content (amole) had positive correlation (r=0.859, p=0.05) with Arg/Am among species. Ammonia content was higher than arginine in p.n. Tryptophan content was greatest in p.n among species and higher than lysine only in p.n. The ratios of TFAA to N(W/W) were in the range of 3.89~4.14 for TFAA and 3.61~3.92 for TFAA plus ammonia.

• Food Science and Preservation
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• v.14 no.6
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• pp.598-604
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• 2007

Process development and standardization are necessary in maintaining high hygienicquality of side dishes. Seasoned perilla leaves are a typical side dish needing process development. In this study the optimum condition for preparing seasoned perilla leaves was investigated experimentally. The best sensory quality was established by response surface methodology. The rinsing and washing method of preparing fresh perilla leaves was optimized to decontaminate the raw material and preserve the product in chilled storage. Washing and rising with 3% salt water reduced the aerobic bacterial count of perilla leaves to 0.55 (log CFU/g), while rinsing reduced the load from 8.08 to 4.27 (log CFU/g). The effect of rinsing method was maintained during subsequent storage of the prepared seasoned leaves at $10^{\circ}C$. There was no significant quality change in the product during chilled storage at $10^{\circ}C$. Soaking in 3% salt water for 1 min, followed by rinsing with tap water, contributed positively to the microbial quality, and is proposed as the optimal preparation method.

• Food Science and Preservation
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• v.20 no.4
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• pp.459-466
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• 2013

This study was carried out in order to investigate sterilization effect and to extend storage periods of the Rubus coreanus by treating with tap water (TW), electrolyzed water (EW) and aqueous chlorine dioxide ($ClO_2$). After each treatment plot was soaked with 10, 50, 100, 200 ppm in each sterilizing solution within 30 sec, each treatment was compared during the storage time at room temperature and refrigerator temperature. As results of total plate count according to temperatures and periods, the microbial sterilizing power of each treatment plot was bigger at EW and $ClO_2$ treatment plots than the TW treatment plot; however, it sharply increased on the high concentration $ClO_2$ treatment plot. Futhermore, the cold storage treatment plot had more outstanding microbial sterilizing power than the room temperature treatment plot. As a result of observing the surface of the Rubus coreanus using scanning electron microscope (SEM), no microbe was seen in EW and $ClO_2$ treatment plot. The results of measuring enzyme activity showed a more significant decrease in EW and $ClO_2$ solutions treatment plot than TW treatment plot but gradually increased with time. The contents of total polyphenol revealed similar values on each treatment. The EW and $ClO_2$ treatment of the Rubus coreanus could be considered as good methods for inhibiting microbial growth in fresh vegetables and fruit, thereby contributing to quality maintenance.

• Journal of architectural history
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• v.16 no.2
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• pp.137-152
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• 2007

The purpose of this article is making investigation of the principal composition of the twin-pagodas in Buddhist temple through ornaments of a case preserving relics of Buddha in the east and west pagodas of Gameunsa temple. This research has an important meaning in clarifying that the concept of placement two Buddhas together with lotus sutra, which was only applied to Bulkuksa temple, has been extended to Gameunsa temple. And this observation gave us a clear explanation for the principal composition at the twin-pagodas in Buddhist temple plans. The author obtained the following conclusion from this article : The cases preserving relics of the Buddha for the west and east pagodas are globally in similar form as the type of a royal palace. But the different points between eastern and western can be seen on the existence of Buddhist statues on the base floor, set-up of the gate at railings, and 4 lion statues at a coner of the base floor. In the western pagoda, there are Buddha statues above the base-floor of the cases preserving relics. These Buddha statues are composed of a boy monks and angels with playing music for the praise of the Sakyamuni Buddha lecturing the Lotus sutra at YoungChui Mountain. On the other hand, in the eastern pagoda, Buddha statues on the cases preserving relics are composed of a the Four Devas and monks as a defending God of the nation of Buddha. In the eastern pagoda, one can see something that does not exist in the western pagoda, which is a gate located in railing of a case preserving the relics. This gate described the scene of the Sakyamuni Buddha entering into the pagoda of 7 treasures. In a corner of the case preserving relics in the eastern pagoda, there is another thing which does not exist in the western pagoda. This is a sculpture of a lion which symbols the seat of Lion supporting the Buddha in the Dabotap(the pagoda of 7 treasures). When we observe the form and structure, the descriptions at the railings, the gate, the shrine, the statue of a lion, and the accessories in jewelries, at the cases preserving the relics in the eastern pagoda, one can realize that they have the same combination structures between the ones at Dabotaps in Bulguksa temple and those in China as well as in Japan, all of which represent the Gyun-Bo-Tap-Pum of Lotus Sutra. Among the distribution rules in the twin-pagodas in Buddhist temple, the application of the ideal of lotus was known to be effected only to Bulguksa temple. But from the result of the present article, it is more clearly proved by applying the Gameunsa temple that the distribution theory in the twin-pagodas in Buddhist temple was in fact based on the ideal of lotus.

• Journal of the Korean Magnetics Society
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• v.9 no.2
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• pp.78-84
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• 1999

$(Ni, Zn)Fe_2O_4$ powders were prepared through self-propagating high temperature synthesis reaction and the effects of initial zinc oxide powder size and oxygen pressure on the magnetic properties of the final combustion products were studied. The ferrite powders were combustion synthesized with iron, iron oxide, nickel oxide, and zinc oxide powders under various oxygen pressures of 0.5~10 atmosphere after blended in n-hexane solution for 5 minutes with a spex mill, followed by dried at 120 $^{\circ}C$ in vacuum for 24 hours. The maximum combustion temperature and propagating rate were about 1250 $^{\circ}C$ and 9.8 mm/sec under the tap density, which were decreased with decreasing ZnO size and oxygen pressure. The final product had porous microstructure with spinel peaks in X-ray spectra. As the ZnO particle size in the reactant powders and oxygen pressure during the combustion reaction increase, coercive force, maximum magnetization, residual magnetization, squareness ratio were changed from 1324 Oe, 43.88 emu/g, 1.27 emu/g, 0.00034 emu/gOe, 37.8$^{\circ}C$ to 11.83 Oe, 68.87 emu/g, 1.23 emu/g, 0.00280 emu/gOe, 43.9 $^{\circ}C$ and 7.99 Oe, 75.84 emu/g, 0.791 emu/g, 0.001937 emu/gOe, 53.8 $^{\circ}C$ respectively. Considering the apparent activation energy changes with oxygen pressure, the combustion reaction significantly depended on initial oxygen pressure and ZnO particle size.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.2
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• pp.138-144
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• 2011

Purpose: The purpose of this study was to evaluate the cleansing effect of recently developed alkaline ionized water, e-WASH, on microorganisms of the denture surface. Materials and methods: Removable partial and complete dentures were randomly assigned to the experimental group of 41 dentures, and the control group of 26. The denture was immersed in the e-WASH solution (experimental group), or tap water (control group) for 5 minutes. The plaque was collected from the denture surface before and after immersion, and smeared on the slide glass. Amount and motility of microorganisms were compared according to the morphology and strain of microorganisms, using the phase contrast microscope. Statistical analysis was accomplished with paired t-test and independent t-test at 95% confidence level (P<.05). Results: 1. The amount of cocci, bacilli, filamentous, spiral/comma, and the motility of bacilli, filamentous, and spiral/comma were decreased after denture cleansing with the alkaline ionized water, e-WASH (P<.05). But in the control group, only the amount of cocci showed a significant difference (P<.05), but no difference from the others. There were no differences in other analysis. 2. In the experimental group, the amount of cocci, bacilli, filamentous, spiral/comma, and the motility of bacilli, filamentous, and spiral/comma were smaller and more inactive compared to the control group (P<.05). Conclusion: These results indicated that the alkaline ionized water, e-WASH could effectively reduce the amount and motility of the experimented microorganisms on the denture surface, and that e-WASH could be recommended as an effective denture cleanser.

• The Korean Journal of Mycology
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• v.41 no.3
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• pp.160-166
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• 2013

Recovery of ${\alpha}$-amylase (EC 3.2.1.1), lignin peroxidase (EC 1.11.1.14), laccase (EC 1.10.3.2), xylanase (EC 3.2.1.8), ${\beta}$-xylosidase (EC 3.2.1.37), ${\beta}$-glucosidase (EC 3.2.1.21) and cellulase (EC 3.2.1.4) from spent mushroom composts (SMCs) of Pleurotus cornucopiae, Pleurotus ostreatus, Pleurotus eryngii, Hericium erinaceum, Lyophyllum ulmarium, Agrocybe cylindracea, Lentinus lepideus, and Flammulina velvtipes were investigated using different extraction buffers. The maximum recovery of the enzymes was mostly detected in SMC extracts with tap water and 0.25% Triton X-100 by shaking incubation (200 rpm) for 2 h at $4^{\circ}C$. The xylanase (152 U/g) and laccase (8.1 U/g) activities were the highest in SMC extracts from F. velvtipes and P. eryngii. In addition, high enzymatic activities of ${\alpha}$-amylase (3.6 U/g) and cellulase (3.4 U/g) was detected in SMC extract of A. cylindracea. Futhermore, cellulase and laccase activities of SMCE from P. eryngii were compared to commercial enzymes.

• Food Science and Preservation
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• v.15 no.1
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• pp.1-8
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• 2008

Quality attributes of fresh-cut pak-choi (Brassica campestris var. chinensis) as affected by hydrocooling and packing were investigated in terms of weight loss, respiration, vitamin C content, total chlorophyll content, microbial load and sensory properties during storage at 4 and $10^{\circ}C$. Fresh pak-choi was trimmed and washed with cold water $(1^{\circ}C)$ as well as tap water $(6^{\circ}C)$ for 30 sec 3 times and then packaged in PP (polypropylene) film bag and PETE (polyethylene terephthalate) bay, and stored for 9 days at 4 and $10^{\circ}C$. Weight loss was decreased by washing and packing generally. Respiration rate was increased slowly over the storage at $4^{\circ}C$. Vitamin C content and total chlorophyll contents of pak-choi packaged within PETE bay decreased gradually during storage. Hydrocooling and packing within PETE bay treatments resulted in approximately 1-2 log CFU/g reduction of microbial load.