• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.2
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• pp.47-56
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• 1997

To examine of possibility protein recycling of shaving scraps contained chrome generated from manufacturing process of leather, the characteristics of hydrolyzed protein that differently treated with MgO as alkaline agent were investigated. In alkaline hydrolysis of saving scraps treated with MgO, MgO had to be treated over 5.0% to maintain over pH 8.0 that is insoluble of chrome. Under the condition of alkaline treated with MgO, the solubility of chrome is low with about 60%. The average molecular weight of hydrolyzed proteins from shaving scraps treated with MgO was about 80~100 KD. The amino acid contents of that were largely collagen proteins such as glycine, alanine and proline, and acidic amino acids such as aspartic acid and glutatamic acid. The contents of Mg, Ca and Na in hydrolyzed protein were too much as liquid fertilizer, and chrome contents was 30~40 ppm that largely decreased in comparing with raw materials (40,000~42,000 ppm).

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.1
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• pp.1-9
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• 2018

Visibility is very poor in tunnel fire because of confined space where the fire may easily lead to the mass casuality incident because of fast smoke spread. In this test, air curtain and the fan were installed at rescue station in a bid to make use of rescue station in safe way during the train fire in undersea tunnel and a full-scale fire test was conducted to identify the applicability of air curtain system. Air curtain system was installed at a real rescue station and the test was continued for 2 minutes till heptane which was used as fire source was completely burned out. When air curtain was working, difference in temperature between inside and outside the platform was $160^{\circ}C$ and carbon monoxide measured inside the platform was less than the case of no air curtain system by 160 ppm. Thus a full-scale fire test demonstrated that the air curtain system installed at rescue station in undersea tunnel was able to effectively block the heat and smoke generated from the fire.

• Journal of Mushroom
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• v.18 no.3
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• pp.208-213
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• 2020

Burkholderia contaminans PSB-A and Burkholderia ambifaria PSB-B were isolated from button mushroom bed to estimate their phosphate solubility. The phosphate-solubilizing abilities of these strains were assessed by measuring the phosphorus content in a single and co-inoculation medium for 7 days. The co-inoculation of these two strains released the highest content of soluble phosphorus (166.3 ㎍ mL^-1) into the medium, followed by single inoculation of B. contaminans PSB-A (143.73 ㎍ mL^-1) and B. ambifaria PSB-B (127.1 ㎍ mL^-1). The highest pH reduction, organic acid production, and glucose consumption were also observed in the co-inoculation medium. According to the plant growth promotion bioassay, co-inoculation enhanced the growth of romaine lettuce much more than the single inoculation (20.4% for leaf widths and 16.6% for root lengths). Although no significant difference was noted between single and co-inoculation of bacterial strains in terms of phosphorous release and plant growth, co-inoculation of PSB may have a beneficial effect on crop growth due to a synergistic effect between the strains.

• Resources Recycling
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• v.31 no.5
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• pp.20-25
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• 2022

In this study, the applicability of microalgae was evaluated for eco-friendly decontamination of cesium-137 (Cs-137) and strontium-90 (Sr-90), which are radioactive nuclides contained in radioactive waste. The monolithic radioactive solution used in the experiment was manufactured at a concentration of 1.5 Bq/mL Cs-137 and 1.0 Bq/mL Sr-90 by diluting a standard radioactive solution and distilled water. This experiment used two types of microalgae, Chlorella Vulgaris was used for Sr-90 decontamination and Hematococcus pluvialis for Cs-137 decontamination. The experimental method is to put the microalgae cultured for 2 weeks into a bottle with a semi-permeable membrane, and then put the bottle in which the microalgae was put into the manufactured radioactive solution, so that the microalgae and the radioactive solution react through the semi-permeable membrane for 48 hours. For the radioactivity concentration analysis of each sample, a gamma-ray nuclide analyzer was used for Cs-137, a γ-ray isotope, and a Liquid Scintillation Count(LSC) was used f or Sr-90, a β-ray isotope. As a result of the experiment, it was confirmed that about 88.0 % of Cs-137 and about 89.7 % of Sr-90 could be decontaminated, and about 98.6 % of Sr-90 was finally able to be decontaminated by the two-stage decontamination method.

• Journal of the Korean Wood Science and Technology
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• v.40 no.3
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• pp.194-203
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• 2012

1-Ethyl-3-methylimidazolium acetate known as efficient biomass pretreatment reagent was used for the extraction of lignin from rigida pine wood (pitch pine), which was called to ionic liquid lignin (ILL), and chemical structural features of ILL were compared with the corresponding milled wood lignin (MWL). The amounts of phenolic hydroxyl groups (Phe-OH) was determined to 10.0% for ILL and 7.2% for MWL, respectively, where those of methoxyl groups (OMe) were 4.9% for ILL and 11.0% for MWL, respectively. The weight average molecular weight (Mw) of ILL (3,995) were determined to ca. 1/2 of that of MWL (8,438) and polydispersity index (PDI: Mw/Mn) suggested that the lignin fragments were more uniform in the ILL (PDI 1.36) than in the MWL (PDI 2.64). The temperature (Tm) corresponding to maximum decomposition rate (Vm) of ILL ($306.6^{\circ}C$) was ca. $35^{\circ}C$ lower than that of MWL ($341.9^{\circ}C$), suggesting that ILL was thermally unstable than MWL, as evidence from the lower Tm for ILL. Moreover, the structural characteristics of ILL and MWL were confirmed by spectroscopic analyses (FT-IR and $^{13}C$-NMR), and these results indicated ionic liquid (1-ethyl-3-methylimidazolium acetate) was chemically or physically bound to ILL.

• Korean Journal of Plant Tissue Culture
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• v.25 no.1
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• pp.33-36
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• 1998

Guzmania was propagated through in vitro culture of lateral shoots. When new shoots grown in greenhouse were cut and cultured in vitro, contamination rate was very high at about 80% in the first stage of in vitro culture. Among cytokinin treatments for agar medium, 2.0 mg/L BA was most effective for shoot multiplication, and those with 0.5 mg/L kinetin and 0.5~1.0 mg/L BA were favorable for shoot multiplication. BA was more effective for shoot multiplication than kinetin, and shoot multiplication was more enhanced when 2.0 mg/L BA was combined with 0.1~0.5 mg/L IAA than 2.0 mg/L BA alone. The medium with 2.0 mg/L BA and 0.1 mg/L IAA showed the highest rate of shoot multiplication with about 8.7 in shoot number, and those with 2.0 mg/L BA and 0.5~1.0 mg/L IAA also resulted in high multiplication of shoots. Shoots were multiplicated more in liquid rotation culture(80 rpm) with the medium containing 0.5 mg/L BA and 0.1 mg/L IAA than liquid stagnating and solid cultures. Regenerated shoots formed roots very favorably in the medium supplemented with 2.0 mg/L IBA.

• Korean Journal of Plant Resources
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• v.22 no.4
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• pp.281-286
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• 2009

Rhodiola sachalinensis is one of the most popular oriental medicines in East Asia. It is a perennial herb, belonging to the family Crassulaceae, which is mainly distributed in mountains at the altitudes of 1700-2500 m in Baek-Du mountain. Cultivation of this species for the production of medicine materials is not easy in nature, because of restrict habitats. In vitro production of roots can be applicable for the production of medicinal materials. Here, we investigated the optimal conditions for induction and proliferation of adventitious roots in in vitro culture system. Leaf, stem and root segments from R. sachalinensis were cultured on Murashige and Skoog(MS) medium supplemented with the various concentrations of IBA(Indole-3-butyric acid)(0.5, 1.0, 3.0, and 5.0 mg/L) and sucrose(10, 30, 50, and 100 g/L). The optimal explant for adventitious root induction was leaf segment. Induction of adventitious roots was highest on MS medium supplemented with 5.0 mg/L IBA and sucrose 30 g/L. In liquid culture, fresh weight of adventitious roots was highest(15.65 g) on 1/3 strength MS liquid medium supplemented with 5.0 mg/L IBA with 30 g/L sucrose. These results revealed the first attempt for the production of adventitious roots in R. sachalinensis.

• Microbiology and Biotechnology Letters
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• v.2 no.3
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• pp.133-140
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• 1974

1) Two xylanase (designed as A and B) of Myriococcus albomyces were purified from an extract of wheat koji culture. Puriscation steps included first ammonium sulfate fractionation followed successively by SE-Sephadex column chromatgraphy. DEAE-Sephadex column chromatography and gel filtration on Sephadex G-100 repectively. 2) The optimum pH and pH stability for crude xylanse were found to be pH 5.0 and pH 4.0-7.0 respectively. 3) The optimium temperature was found to he 5$0^{\circ}C$ and for the thermal statbility of xylanase, the enryme incubated at $65^{\circ}C$ for 60min did not affect their stability. 4) The purised xylanase A and B were considered as liquefying xylanase and saccharogenic xylauase repectively. 5) The Bylanase A was most active at pH 4.0 and range of pH 3.0-8.0 at 3$0^{\circ}C$ for six hrs. The B was most active at pH 5.0 showing stability range of pH 4.0 to 8.5 at 3$0^{\circ}C$ for 6 hrs. incubation respectively. The Optimum temperature of xylanase A and B were found to be 7$0^{\circ}C$ and $65^{\circ}C$ for 60min repectively.

• Geophysics and Geophysical Exploration
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• v.9 no.1
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• pp.10-18
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• 2006

We measured the changes in P-wave velocity that occur when injecting $CO_2$ in gaseous, liquid, and supercritical phases into water-saturated anisotropic sandstones. P-wave velocities were measured in two cylindrical samples of Tako Sandstone, drilled along directions normal and parallel to the bedding plane, using a piezo-electric transducer array system. The velocity changes caused by $CO_2$ injection are typically -6% on average, with maximum values about -16% for the case of supercritical $CO_2$ injection. P-wave velocity tomograms obtained by the differential arrival-time method clearly show that $CO_2$ migration behaviour is more complex when $CO_2$ flows normal to the bedding plane than when it flows parallel to bedding. We also found that the differences in P-wave velocity images were associated both with the $CO_2$ phases and with heterogeneity of pore distribution in the rocks. Seismic images showed that the highest velocity reduction occurred for supercritical $CO_2$ injection, compared with gaseous or liquid $CO_$ injection. This result may justify the use of the seismic method for $CO_2$ monitoring in geological sequestration.

• Journal of Plant Biotechnology
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• v.34 no.1
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• pp.1-6
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• 2007

Effect of BA concentrations and culture methods on in vitro plant multiplication from shoot-tip cultures of Wasabia japonica was studied. Shoot-tips with leaf primordia and apical meristem were cultured on MS basal medium for all the experiments. Liquid medium for 2 weeks followed by semi-solid medium for 4 weeks containing 1.0 mg/L BA was the best to number of shoots (22.8) and shoot length (3.5 cm). Shoots proliferated could be divided into ca. 5 to 11 of cultures for the multiplication of plantlets. Divided plantlets showed root formation (90%) well onto MS basal medium without growth regulators like IBA and NAA. After rooting, all the plantlets transferred into the pots containing composed soil (bio-media Co., peatmoss $8{\sim}10%$, coir dust $66{\sim}70%$, zeolite $13{\sim}17%$, vermiculite $3{\sim}7%$, perlite $2{\sim}4%$) and grown well into whole plants with multiple shoots.