• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.615-623
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• 1998

The garlic juices were extracted and concentrated by heating at $90^{\circ}C$, by using a rotary vacuum evaporator at $45^{\circ}C$, or by freezing at $-50^{\circ}C$ until the volume was reduced to 70% of the original volume. The concentrated juices were kept at $4^{\circ}C\;or\;25^{\circ}C$ for 60 days and the changes of bacteria and color were monitored every 10 days. Flavors of the raw garlic juices, concentrated garlic juices, and garlic powder by hot-air drying were analyzed monthly using GC and GC/MS. The CFUs/mL of mesophilic and psychrotrophic bacteria in the garlic juice concentrated at $90^{\circ}C$ were lower about 1 to 2 log cycles than those of other concentrated juices. Hunter L, a, and b values in the raw garlic raw juice and the juice concentrated at $-50^{\circ}C$ significantly increased at the beginning of storage, in particular, when they were stored at $25^{\circ}C$. The garlic juice concentrated at $45^{\circ}C$ showed relatively low L value but the juice concentrated at $90^{\circ}C$ showed high a value. The main peaks in chromatograms of volatile components identified by GC/MS were 3,3'-thiobis-1-propene, di-2-propenyl disulfide, 3-(methylthio)-1-propene in the raw garlic juice and the concentrated juices, and the juices concentrated at $45^{\circ}C\;or\;-50^{\circ}C$ showed relatively high preservation of garlic flavor.

• Journal of Life Science
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• v.13 no.1
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• pp.9-14
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• 2003

Seed germinability might be highly related to seedling establishment. The experiments were carried out to evaluate the effect of presowing treatments of aging, priming, $GA_3$ , prechilling and water imbibition, different temperatures and light quality during germination on germination of gourd (Lagenaria siceraria Standl.) seeds. Aging treatment with different temperatures and periods was done by the accelerated aging method. Priming using KNO$_3$ and $GA_3$ treatment for 24 hours were done at 100 mM and at 0.01 mM before a week prechilling. The germination tests using a week prechilled seeds were done at 10, 20 and $30^{\circ}C$ on the condition of darkness, and also with blue, red, far-red light and darkness as light quality treatments. FR-yongjadaemok and FR-kunghap were used as test cultivars and their daily germination rates were measured at treatment levels. Germination rates were reduced in the seeds aged at $45^{\circ}C$ for 6 days. Prechilling showed the highest and fastest rate among the four presowing treatments but the two other presowing treatments had similar or less rates than water imbibition. Prechilling done before sowing enhanced the low vigor seeds, and accelerated the germination of cv. FR-kunghap at 20 to $30^{\circ}C$ and with blue, red light or darkness during germination although far-red light inhibited their germination.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.85-91
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• 1985

The change of acid-phosphatase in Fuji apples Was investigated in terms of storage temperature and pressure. The firmness, sugar contents, acidity and activity of acid-phosphatase with electrophoretic pattern were studied during storage. The firmness, sugar contents and acidity were decreased during storage. Ratio of decrease was greater at normal temperature than low temperature and normal atmosphere than sub-atmosphere. Acid phosphatase activity of apples was mainly existed cell wall fraction and increased with climacteric rise and decreased later. The activity was higher at normal temperature than low temperature and at atmosphere than sub-atmosphere. The optimal temperature and pH were $45^{\circ}C$ and pH 5.6, respectively. In stability of heat and pH, enzyme solution was stabilized to $30^{\circ}C$ and pH 5-8. Electrophoretic pattern of enzyme solution extracted from sub-atmospheric pressure with low temperature and normal atmospheric pressure with normal temperature yielded two activity bands during storage.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.44-48
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• 2008

This experiment was conducted to examine the effect of injecting cool air from an abandoned mine during the summer time for the growth of Doritaenopsis. The air temperature of abandoned mine in Boryeong was $12{\sim}14^{\circ}C$. The day and night temperatures were set at $22^{\circ}C$ and $20^{\circ}C$, respectively, from June to August in the experimental plastic house. This temperature range was within the suitable range for floral induction in Doritaenopsis. Average outside temperature was $28.4{\sim}32.8^{\circ}C$. The 3% of the crop developed flower stalk in 20 days after the treatment initiation, 65% in 45 days, and 100% in 90 days. The flower stalk length was short (48.7cm) in 30 days and long (62.4cm) in 60 days of treatment. The flower stalk length became longer as time passed. Flower spike and number of florets per stalk displayed the same tendency. Number of nodes was 6~7 and was not affected by the period. The first blooming appeared on 15th of September at 45 days and blooming tended to appear late as the period is lengthened. When the cool air from an abandoned mine was injected, the crop formed flower stalk three months earlier and bloomed four months earlier than the untreated control.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.305-314
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• 2017

The purpose of this study was to develop the high efficiency of ginseng by using microwave low temperature vacuum drying technology. In red ginseng manufacturing processes, the study results compared the hot-air drying red ginseng dried during 24hours in $60-70^{\circ}C$ and redried during 72hours in $40^{\circ}C$ after the steaming ginseng with the red ginseng dried in microwave low temperature vacuum dryer on condition that 900 watt, 2.45 MHz, 50 mmHg during 5 hours and redried during 2 hours on 750 mmHg after the steaming ginseng about observation of tissue, sensory evaluation and a change of ginsenoside and crude saponin content. As a result, the red ginseng in microwave low temperature vacuum was had high brightness, the surface turned into porosity tissue and added more flavor, decreased bitterness highly on the contrary increased sweetness at the same time that elevated the comprehensive preference. Moreover, In a short time, the content of ginsenosides $Rg_1$ and $Rb_1$ increased about sixfold, eightfold in one time zone but there were no wide difference in content of $Rg_3$ as compared to the hot-air drying red ginseng. Finally, content of crude saponin was increased widely at 10-20 minutes and stayed high crude saponin content consistently. Therefore, this result indicated that the red ginseng in microwave low temperature vacuum increased extraction yields of the ginsenosides and crude saponin through a change of porosity tissue and improved flavor and texture compare with the general hot air dried red ginseng in a short time. According to these results, that provided that could increase the preference about red ginseng.

• Korean Journal of Poultry Science
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• v.28 no.2
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• pp.83-89
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• 2001

Newcastle disease virus, CBP-1 strain isolated from Korean pheasants was passaged for 173 times by 9-day-old specific pathogenic free (SPF) embryonated eggs at $37^{\circ}C$ (parent strain) and subsequently passaged for 15 (cold attenuation (CA) -15) and 30(cold attenuation (CA) -30) times by 10-day-old of commercial broiler chicks embryonated eggs at $29^{\circ}C$, respectively, The Physical and chemical properties (sensitivity to lipid solvents, low pH and thermostability), pathogenicity (mean death time, intracerebral pathogenic index and intravenous patho-genic index), safety, booster or protective effect and characterization of temperature sensitivity were measured in cold attenuated CA-15 or 30 strain and compared to those of parent CBP-1 strain. NDV, CBP-1 CA-30 strain acquired cold attenuation and decreased infectivity at $41^{\circ}C$ compared to those of parent strain grown at $37^{\circ}C$. It lost hemagglutination activity (HA) and cell infectivity at $56^{\circ}C$ for 30, 60, and 120 Min. CA-30 strain treated with ethyl ether also lost its HA and cell infectivity. Both CA-30 and parent strains exhibited a little resistant to HA at pH 3.0 glycine HCI buffer. Intracerebral pathogenic index (ICPI) and intravenous pathogenic index (IVPI) of parent strain were 1.12 and 1.45, but decreased to 0.75 and 0.00 in CA-30 strain, respectively. The safety was evaluated by mortality in chicks inoculated with 10$^{4.0}$ EID$_{50}$ /0.1 ml. The mortalities of parent, CA-30 and commercial Bl strains were 17.5, 12.0 and 0.0%, respectively. The safety of CA-30 strain was higher than that of parent strain. The booster effects of CA-30 strain and parent strain performed in 4-week-old chicks after being vaccinated with primary commercial Bl strain.

• Korean Journal of Weed Science
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• v.11 no.3
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• pp.219-223
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• 1991

Effects of media and low temperature on germination of weeds were examined to get basic information for establishing weed control methods. Soil and agar(0.4%) was good media for germination of weeds at laboratory. Germination was improved by placing weed seeds at 5$^{\circ}C$ low temperature for 10-20 days. Germination was improved by storing weed seeds in water absorbed gauge and in vinylbag at 5$^{\circ}C$ low temperature for 30-40 days. Germination was increased by burial of weed seeds at 10cm of soil depth for 30-60 days.

• Korean Journal of Microbiology
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• v.38 no.1
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• pp.45-49
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• 2002

Bradyrhizobium japonicum is a soil bacterium with a unique ability to infect the roots of leguminous plants and establish a nitrogen-fixing symbiosis, which has been used as a microbial manure. In this study, we examined the stress response after pretreatment of cells with cold temperature. When pre-treated with cold temperature ($4^{\circ}C$) for 16 hr, B. japonicum increased the viability in subsequent stress-conditions such as alcohol, $H_2O_2$, heat, and dehydration. For cold adpatation, cultured B. japonicum was exposed to $4^{\circ}C$. Upon subsequent exposure to various conditions, the number of adapted cells pretreated by cold adaptation was 10-1000 fold higher than that of non-adaptated ones. It appeared de novo protein synthesis occurred during adaptation, because a protein synthesis inhibitor, chloramphenicol abolished the increased stress tolerance. By using a degenerate PCR primer set, a csp homolog was amplified from B. japonicum genome and sequenced. The deduced partial amino acid sequence of the putative Csp (Cold shock protein) shares a significant similarity with known Csp proteins of other bacteria.

• Food Science and Preservation
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• v.13 no.2
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• pp.138-143
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• 2006

Clarified apple juice was prepared using different clarification methods including centrifugation, ultrafiltration (UF), and combined treatment (CT). Effects of clarification methods as well as other qualify parameters were investigated Clarification was clearly improved with an increase in centrifugation speed and towering temperature. Especially, lowering the temperature led to a decrease in turbidity values at 5,000 rpm. The optimum condition for centrifugation process was $5^{\circ}C$ and 10,000 rpm, respectively. UF and CT were very effective to produce clarified apple juice. The optimum condition of UF process was $45^{\circ}C$ and 150 kPa considering flux and turbidity. L*-values were increased while a*-values were decreased significantly after clarification regardless of methods (P<0.05). Vitamin C was most retained in the clarified samples using CT.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.1
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• pp.19-24
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• 2007

The effects of $B_2O_3-SiO_2-R(R;CaO,\;BaO,\;ZnO,\;Bi_2O_3)$ borosilicate glass system on the sintering behavior and microwave dielectric properties of ceramic/glass composites were investigated as functions of modifier, glass addition ($30{\sim}50\;vol%$) and sintering temperature ($500{\sim}900^{\circ}C$ for 2 hrs). The addition of 50 and 45 vol% glass ensured successful sintering below $900^{\circ}C$. Sintering characteristics of the composites were well described in terms of modifier. Borosilicate glass enhanced the reaction with $Al_{2}O_{3}$ to form pores, second phases and liquid phases, which was responsible to component of modifier. Dielectric constant (${\varepsilon}_{r},\;Q{\times}f_{o}$) and temperature coefficient of resonant frequency (${\tau}_{f}$) of the composite with 50 and 45 vol% glass contents($B_{2}O_{3}:SiO_{2}:R=25:10:65$) demonstrated A-CaBS(7.8, 2,560 GHz, -81ppm/$^{\circ}C$), A-BaBs(5.8, 3.130 GHz, -64 ppm/$^{\circ}C$), A-ZnBS(5.7, 17,800 GHz, -21 ppm/$^{\circ}C$), A-BiBs(45 vol% glass in total)(8.3, 2,700 GHz, -45 ppm/$^{\circ}C$) which is applicable to substrate requiring an low dielectric properties.