• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.36-43
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• 2006

Using fluidized bed type fast pyrolysis system (capacity 400 g/h) bio-oils were produced from beech (Fagus sylvatica) and softwood mixture (spruce and larch, 50:50). The pyrolysis was performed for 1~2 s at the temperature of $470{\pm}5^{\circ}C$. Pyrolysis products consisted of liquid form of bio-oil, char and gases. In beech wood bio-oil was formed to ca. 60% based on dry biomass weight and the yield of bio-oil was 49% in soft wood mixture. The moisture contents in both bio-oils were ranged between 17% and 22% and the bio-oil's density was measured to $1.2kg/{\ell}$. Bio-oils were composed of 45% carbon, 47% oxygen, 7% hydrogen and lower than 1% nitrogen,which was very similar to those of original biomass. In comparison with oils from fossil resources, oxygen content was very high in bio-oils, while no sulfur was found. More than 90 low molecular weight components, classified to aromatic and non aromatic compounds, were identified in bio-oils by gas chromatographic analysis, which amounted to 31~33% based on the dry weight of bio-oils.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.16-21
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• 2008

This study was carried out to obtain the basic data for the mycelial growth conditions of cauliflower mushroom, Sparassis crispa. Twenty-one isolates were collected from domestic and abroad. The optimal temperature and pH for the mycelial growth of these isolates were $23^{\circ}C$ and pH 6.0, respectively. The mycelial growth was the best in the HBA medium, but very poor in the Lilly medium. However no mycelial growth in the CzapekDox medium. The utilization of carbon source was the best with fructose, and that of nitrogen source was the best with glutamine when compared to other tested sources. The selected isolate ASI150010 produced the highest mycelial weight in liquid culture containing soybean mill ($15\;g/{\ell}$) and potato ($200\;g/{\ell}$) extract. And uncleaned rice, wheat and barley were found to be good substrates for the mycelial growth S. crispa.

• Korean Journal of Animal Reproduction
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• v.23 no.3
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• pp.221-227
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• 1999

Successful cryopreservation of bovine immature oocytes can increase availably of oocytes for the in vitro fertilization or nuclear transfer. However, it was not reported successful development to the blastocyst stage following in vitro fertilization of cryopreserved bovine immature oocytes. The objective of this study was to determine the incidence of survival, meiotic maturation, fertilization and in vitro development of cryopreserved bovine immature by ultra rapid cooling methods. The oocytes were adversely affected by brief exposure to EFS40 solution in electron microscope grids and plunged directly into liquid nitrogen. After such ultra-rapid cooled immature oocytes were warmed, 78% of oocytes were matured to the metaphase II stage, 50% of oocytes were fertilized after insemination, and 5% of oocytes were developed to the blastocyst stage. Different sodium concentration of sodium ion in the freezing medium did not affect survival, maturation, fertilization and in vitro development of cryopreserved oocytes. These results suggested that immature bovine oocytes can be cryopreserved by ultra-rapid cooling methods.

• Reproductive and Developmental Biology
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• v.35 no.3
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• pp.385-390
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• 2011

The purpose of this study was undertaken to evaluate of cryopreservation efficiency in ${\alpha}$ 1,3-galactosyltransferase knock-out(GalT KO) cloned miniature pig sperm. To compare ability of frozen-thawed sperm characteristics, three different pig strains (GalT KO) cloned miniature pig, PWG miniature pig and Duroc were used. The ejaculated semen from the three pig species was diluted with same volume extender and added to LEY solution for freezing. The diluted semen was placed in 0.5 ml straws, and freezing was initiated by exposing the straws to liquid nitrogen ($LN_2$) vapours for 10 min before placing them into $LN_2$ for cryopreservation. After thawing, the sperm ability were assessed for viability (SYBR-14/PI staining), abnormality (Rose Bengal staining), and acrosome status (intactness, intensity and capacitation) (chlorotetracycline, CTC staining). The viability of frozen-thawed GalT KO pig sperm had no significant difference as compared with Duroc and PWG miniature pig sperm. However, The CTC pattern of frozen-thawed GalT KO cloned miniature pig spermatozoa showed significantly lower rates in F pattern and AR pattern (p<0.05) and significantly higher rates in B pattern than Duroc and PWG miniature pig (p<0.05). The abnormality of GalT KO cloned miniature pig sperm was significantly lower as compared to Duroc and PWG miniature pig sperm (p<0.05). In conclusion, GalT KO cloned miniature pig semen can be cryopreserved successfully and used for artificial insemination reasonably.

• Korean Journal of Environmental Agriculture
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• v.32 no.2
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• pp.142-147
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• 2013

BACKGROUND: This study was conducted to monitor residual pesticides in domestic agricultural products and to assess their risk to human health. METHODS AND RESULTS: 123 samples containing both general and environment-friendly certified agricultural products were purchased from traditional domestic markets and supermarkets in six provinces of Korea. Multiresidue analyses of one hundred twenty-two pesticides except for herbicides were performed with gas chromatography-electron capture detector, gas chromatography-nitrogen/phosphorus detector, and high-performance liquid chromatography. Sixteen pesticides were detected in 45 agricultural product samples, which were 38 general, 6 low pesticide and 1 of GAP agricultural product samples and the detection rate was 33.6%. Pesticides detected in agricultural product samples were cypermethrin, lufenuron, fenvalerate, bifenthrin, chlorfenapyr and iprodione. Residual concentration of 18 samples were exceeded the recommended maximum residue limit set by Ministry of Food and Drug Safety and two kinds of unregistered pesticides in korea were also detected in two samples. CONCLUSION(S): In order to do risk assessment by agricultural products consumption, estimated daily intake of residual pesticides were determined and compared to acceptable daily intake, referring to %ADI values. The range of %ADI values was from 0.038% to 2.748%. Taken together, it demonstrates the pesticides found in agricultural products samples were below the safety margin, indicating no effect on human health.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.6
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• pp.732-741
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• 2020

Environmental regulations have recently been strengthened. Consequently, floating LNG(Liquefied Natural Gas) power plants are being developed, which are new power generation plants that generate electricity by utilizing LNG. A floating LNG power plant generates BOG(Boil-Off Gas) during its operation, and the system design of such a plant should be capable of removing or re-liquefying BOG. However, the design of an offshore plant differs according to the marine requirements. Hence, a process simulation model of the BOG re-liquefaction system is needed, which can be continuously modified to avoid designing the floating LNG power plant through trial and error. In this paper, to develop a model appropriate for the floating LNG power plant, a commercial process simulation program was employed. Depending on the presence of refrigerants, various BOG re-liquefaction systems were modeled for comparing and analyzing the re-liquefaction rates and liquid points of BOG. Consequently, the BOG re-liquefaction system model incorporating nitrogen refrigerants is proposed as the re-liquefaction system model for the floating LNG power plant.

• Korean Journal of Animal Reproduction
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• v.11 no.3
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• pp.155-160
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• 1987

This study was carried out to determine the effects of cryoprotectants, freezing and thawing rates on the survival of 8-cell mouse embryos. The female ICR mice were induced to superovulated by intraperitoneal injections of 5 i.u. PMSG and 5 i.u. HCG given 48h apart and then were paired with males of the same strain. They were killed and embryos were flushed from the oviducts and uteri on 3 days after injection of HCG. Embryos were flushed with modified Dulbecco's phosphate buffered saline and equilibrated with 1.5M-dimethyl sulfoxide (DMSO) or 1.5M-glycerol by 3-step procedure. The freezing rates of the embryos were 1$^{\circ}C$/min from room temperature to -5$^{\circ}C$ and the embryos were seeded at -5$^{\circ}C$. After being held for 3 min at the seeding temperature, the rates were 0.3$^{\circ}C$/min from -5$^{\circ}C$ to -35$^{\circ}C$. From -35$^{\circ}C$ to -7$0^{\circ}C$, the rates were divided into 0.1$^{\circ}C$/min, 1$^{\circ}C$/min and 1$0^{\circ}C$/min, respectively. After being held for 5 min at -7$0^{\circ}C$, the embryos were plunged directly into liquid nitrogen. The embryos were thawed at 4$^{\circ}C$/min and 12$^{\circ}C$/min from -196$^{\circ}C$ to 37$^{\circ}C$, and for 2 min in 37$^{\circ}C$ water bath, respectively. The average number of ovulation points and embryos recovered were 42.7 and 34 appearing 79.5% recovery rate. Eight cell embryos in the embryos recovered were 26.3. The survival rates of embryos according to the freezing rates in the presence of 1.5M-DMSO were 73.5~80.6% at 0.1$^{\circ}C$/min, 75.0~79.5% at 1$^{\circ}C$/min and 52.8~54.7% at 1$0^{\circ}C$/min, but in the presence of 1.5M-glycerol were 62.9~67.6% at 0.1$^{\circ}C$/min, 61.4~68.3% at 1$^{\circ}C$/min and 25.5~30.2% at 1$0^{\circ}C$/min. The survival rates of embryos were not affected by the thawing rates.

• Analytical Science and Technology
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• v.23 no.1
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• pp.89-96
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• 2010

In general, three types of fingerprints could be found at the crime scene: visible, plastic, and latent fingerprints. Examples of visible fingerprint include those made by blood, paint or ink. Plastic fingerprint are made from an impression of the finger on soft material as soap, wax, etc. Latent fingerprint are those of the invisible one to the human eye. Oil-contaminated fingerprints remained in the evidence, that are contaminated with the soybean oil, engine oil, lubricating oil or grease. Oil-contaminated fingerprints are special types of fingerprint evidence but the research for developing method regarding oil-contaminated fingerprints is a few. In this study, ultraviolet light source was employed for untreated oil-contaminated prints and the freeze-dry method with liquid nitrogen for freeze oil residue on the surfaces with sequence of developing oil-contaminated fingerprints with black and magnetic powders, cyanoacrylate (CA) fuming, Basic Yellow 40. The types of oil chosen for the experiment were soybean oil, LSA oil, engine oil and material surfaces selected for the experiment were glass, plastic aluminum plates. The aims of this study were to determine the appropriate developing methods for oil-contaminated fingerprints.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.23-28
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• 2003

The present study was undertaken to investigate the effects of PVP concentration and exposure temperature to vitrification solution on the post-thaw survival, in vitro maturation and development of immature bovine oocytes (germinal vesicle stage). The vitrification solution (VS) consisted of 40% ethylene glycol (EG)+0.5 M sucrose (S)+10% FBS. PVP was added to VS: 0%, 5% or 10%. The cumulus-oocyte complexes (COCs) were diluted in VS as one step, after 2 min the COCs were loaded in straw and vitrified by direct immersion into liquid nitrogen. For thawing, the straws were plunged into $30^{\circ}C$ water bath for 10s. After thawing, the oocytes were diluted in 0.5 M (in DPBS with 10% FBS) sucrose solution for 5 min. The survival rate (FDA-test and trypan blue) of immature bovine oocytes was measured. The survival rate was higher in 5% PVP (91.5%) than in 0% (64.2%) or in 10% PVP (79.7%). The proportion of metaphase II formation was 69.35% in control (no vitrified COCs), 9.3% in 40% EG+0.5 M S+0% PVP and 21.05% in 40% EG+0.5 M S+5% PVP (p<0.05). The effect of room temperature ($25^{\circ}C$ for 10 min) and cold temperature ($4^{\circ}C$ for 10 min) on COCs were determined in this study. After IVF, the cleavage and blastocysts rate of oocytes exposed to room temperature and cold temperature in VS+5% PVP was significantly different (2 cell: 63.20% vs 37.97%, blastocysts: 18.40% vs 2.53%). The cleavage rates of frozen-thawed oocytes were 20.53% with PVP and 22.13% without PVP (p>0.05). Two out of 151 oocytes (1.32%) developed to blastocyst stage after frozen-thawed with 5% PVP (p>0.05). Development of oocytes after frozen-thawing to the 2 cell were not significantly affected with or without PVP following IVF. However, the vitrification of immature bovine oocytes with PVP maintained the ability to develop to the blastocyst stage after IVM-IVF and IVC, while no blastocysts were obtained from oocytes vitrified without PVP. These results suggested that PVP has a protective role for vitrification of immature bovine oocytes as far as survival is concerned, however, the protection was not sufficient enough to support blastocyst formation.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.283-287
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• 1999

This study was carried out to select the most suitable soybean cultivars for the quality kanjang preparation. Six cultivars of soybean, Taekwangkong, Kumjungkong #1, Sinpaldalkong #2, Hwangkeumkong, Danbaegkong and Danyeobkong, were used as the raw materials for kanjang preparations. Grain type meju was prepared by the inoculation of Bacillus subtilis var. globigii seed culture on the cooked soybean of respective cultivar and cultivation at $30^{\circ}C$ for 10 days. Two month matured respective kanjang mash, which was prepared by mixing meju and 20% salt brine in the ratio of 1 : 3, was separated and the liquid portions were used as kanjang samples for this work. The highest crude protein content of 47.5% was obtained from Danbaegkong cultivar among six soybean cultivars tested. High sugar soybean cultivars were found to be Kumjungkong l and Danbaegkong and the content 15.87% and 13.33% respectively. The highest total nitrogen(TN) content of 1.18% was shown from Danbaegkong kanjang. Although the major free organic acid in kanjang was found to be succinic acid, no significant differences in free organic acid and sugars content were observed among cultivars. The highest free total amino acids(TA) and glutamic acid(GA) content in kanjang was observed to be 3365 mg% and 734.44 mg% respectively from Danbaegkong kanjang. Danbaegkong cultivar soybean which was shown to contain the highest crude protein was found to be the most suitable one for the preparation of quality kanjang with high TN, GA content and GA/TA ratio.