• Plant Resources
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• 제2권2호
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• pp.88-95
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• 1999

These experiments were conducted to evaluate the variability of seed germination and seedling growth with different levels of polyethylene glycol(PEG 6,000) solution in onion seed. Average germination percentage of seed primed in PEG solution with 1.00 and 0.75 MPa was higher than control, and that of seed primed in 1.50MPa was lower than unprimed control. Germination percentage(GP) of seed primed for 5 days was highest, and as the primed days become long, the GP was decreased. The GP of airation seed during the primed was higher than that of unairation seed, about 5% , respectively. The GP of washed seed after primed was higher than that of unwashed seed, but that of redried seed after primed was lower than that of the others. The highest GP cultivar was Chunjoogoohyung and the lowest GP cultivar was Seouldego in unredried seed after primed, but Chunjoojoonggo was highest and Jungpoonwhang was the lowest cultivar in redried seed after primed. As the PEG concentration increased, the seedling length(SL) was shortened, and seed primed for 15 days was longer than other treatments. The SL of primed seed was similar to GP. The SL of washed seed after primed was longer than that of others, but that of redried seed after primed was shortest among the others. The SL of Chunjoojoonggo and Nongwoodego was longest and Seouldego was shortest among the cultivars in unredried seed after primed, but that of Chunjoogoohyung and Chunjoojoonggo was longest and Seouldego was the shortest cultivars in redried seed after primed.

• 한국작물학회지
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• 제44권2호
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• pp.138-142
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• 1999

An experiment was carried out to find out the changes in morphology, sugars, and $\alpha$-amylase activity during the priming of rice seeds (Oryza sativa L. cv. ＇Ilpumbyeo＇). For priming, seeds were soaked in -0.6 MPa PEG solution at 15$^{\circ}C$ for 4 days (properly primed) and at $25^{\circ}C$ for 4 and 10 days (over-primed) and dried at room temperature. The size of coleoptile and differentiated leaves of properly primed seeds were bigger and coleoptile was separated from the other part of embryo compared with non-primed and over-primed seeds. As priming of seeds advanced, compound starch grains in the endosperm disintegrated into tiny starch granules, and small holes were found in the tiny starch granules and a cavities developed between embryo and endosperm. The radicle and plumule of properly primed germinating seeds developed faster than non-primed and overprimed germinating seeds. Sucrose, maltose, and raffinose contents of properly primed seeds decreased, while content of glucose and fructose and $\alpha$-amylase activity increased. However, sugar content and $\alpha$-amylase activity of over-primed seeds were lower compared with non-primed seeds or properly primed seeds.

• 원예과학기술지
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• 제31권6호
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• pp.700-705
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• 2013

This study was initiated to evaluate hydrophilic polymers (hydrogels) as a new solid matrix medium for seed-priming of Heteropappus arenarius Kitam. Solid matrix priming (SMP)-media were prepared with the combination of Na- and K-based hydrogels and hydrogels with three different dry levels (DC; 70%, 80%, and 90%). Priming was performed in the dark at 15 or $20^{\circ}C$ for 24 hours, and all primed seeds were incubated at $20^{\circ}C$ in the dark for the germination test. Non-primed seeds and seeds primed with distilled water (DW) were also included. To reach the germination rate of 50% ($T_{50}$), it took 4.0 days for non-primed seeds, and 3.6 and 3.9 days for DW-primed seeds at 15 and $20^{\circ}C$, respectively. Na-based hydrogel-primed seeds with 70% DC (Na 70%) showed the fastest germination, which respectively took and 1.9 and 1.8 days at 15 and $20^{\circ}C$ to $T_{50}$. K-based hydrogel-primed seeds with 70% DC showed the fastest germination among K-based hydrogels with various DC levels, but it took 0.6 days more to $T_{50}$ compared to Na 70%. The hydration rate (HR) of DW-primed seeds was 37% lower than that of Na 70%-primed seeds at $15^{\circ}C$ priming temperature, which indicates that Na 70% priming is the best solid matrix priming condition for promoting the germination of H. arenarius seeds.

• Restorative Dentistry and Endodontics
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• 제21권1호
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• pp.321-338
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• 1996

The purpose of this study was to evaluate the effect of moistening and air-drying of acid conditioned dentin and enamel on the marginal microleakage. In this study, Class V cavity were prepared on both buccal and lingual surface of sixty extracted human premolars with cementum margin. These specimens were randomly devided into three groups and three dentin adhesives(Scotchbond Multi-Purpose, All bond 2, Prisma Universal Bond 3) were applied to each group. The specimens in each group were subdevided into four groups (Wet/primed, Dry/primed, Wet/not primed, Dry/not primed) and the etched dentin and enamel surface were treated these four surface treatments prior to the placement of a bonding agent or adhesive. Wet/primed group was simply blot-dried with a damp facial tissue before primer placement ; Dry/primed group was air dried for 30 seconds before the placement of a primer ; Wet/not primed group and Dry/not primed group were not primed after blot dried and air dried for 30 seconds each group. The bonding agent and composite resin were applied for each group. All specimens were exposed to 500 cycle of thermal stress. Specimens were placed in a silver nitrate solution and then sectioned buccolingually through the center of the restoration. The dye penetrations of the specimens were observed with a stereo microscope. The statistical test were applied to the results using a one way analysis variance (ANOVA) and Duncan's multiple range test. The aspects of silver ion penetration into the resin/dentin interface were examined under scanning electron microscopy. The results were as follows. 1. In all groups, the enamel margin showed significantly lower leakage value than the cementum margin (p<0.05). 2. Regardless of various surface treatment and dentin adhesives, there was no significant difference at the enamel margins (p>0.05). 3. At the dentin margins, the leakage values of Dry/not primed group showed significantly higher than that of the other groups (p<0.05). The leakage values of Wet/primed group showed significantly lower than that of the other groups, but, there was no significant difference between Wet group and Dry group. 4. There was no significantly difference between the dentin adhesives regarding the surface treatments in all groups(p>0.05). 5. On the backscatterd scanning electron microscopy observation, the penetration of the silver ion occured at the bonding resin/dentin interface. In the Wet/primed group, resindentin hybrid zone and resin penetration into the dentin was observed. The resin tags were compactively formed to a thickness of $3\sim4{\mu}m$ at the upper part of dentinal tubules. In the Dry/primed group, the thickness of the hybrid zone and the diameter, depth of the resin tags diminished. In the Non-primed groups, the hybrid zone was not identified and few resin tag was observed. There was the gap formation in the resin/dentin interface.

• 한국작물학회지
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• 제44권2호
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• pp.134-137
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• 1999

An experiment was carried out to determine the effects of priming and growth regulator treatment of seeds on the emergence and seedling growth of rice, Oryza sativa L. (cv. 'Ilpumbyeo'). Normal seeds were primed in a -0.6 MPa polyethylene glycol solution at 15$^{\circ}C$ for four days with air-bubbling. Then both primed and non-primed seeds were soaked in water, 100 ppm GA$_3$, 2 ppm ABA, and 10 ppm kinetin solutions for 24 hours. The seeds were planted in soil at 3 and 5 cm depths and allowed to germinate in a growth cabinet at 2$0^{\circ}C$. Generally, the emergence rate at the 3 cm seeding depth was higher and emerged faster compared with the 5 cm seeding depth. The emergence rate of primed seeds was higher and emerged faster compared to non-primed seeds. GA$_3$ and kinetin treatments were the most effective to improve the emergence rate of non-primed seeds. Coleoptile length at the 5 cm seeding depth was longer than that at the 3 cm seeding depth. Leaf number, plant height, and root length of primed seedlings were higher compared with non-primed seeds. GA$_3$ promoted the elongation of plant height and mesocotyle length.

• 접착 및 계면
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• 제12권3호
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• pp.99-104
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• 2011

21세기 들어 자동차 도료산업은 엄격한 환경규제 및 생산 효율성 향상 및 더 낮은 생산비용으로 자동차용 도료를 생산하기 위하여 세정 및 전처리 과정을 삭제한 pre-primed 도장 시스템이 연구되고 있다. 이러한 pre-primed 도료 시스템의 경우, 차체 조립 전 단계에 강판이 유기 도막으로 도장되어있기 때문에 기존의 용접을 통한 조립이 힘들어 용접공정을 대체할 수 있는 새로운 비용접식 접합기술의 개발이 필요한 실정이다. 본 연구에서 비용접식 pre-primed 시스템에 적용하기 위하여 유연성과 성형성이 향상된 polyester계의 primer 1과 polyurethane계의 primer 2를 개발하였다. 개발된 도료의 물리적인 물성과 도장면의 부착력 평가 결과, primer 1이 primer 2에 비하여 연필경도, 내용제성, 유연성 및 접착제와의 부착력이 뛰어남을 알 수 있었으며, 용접공정을 대신한 비용접식 pre-primed 시스템의 가능성을 확인할 수 있었다.

• 한국작물학회지
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• 제44권3호
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• pp.273-276
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• 1999

Some metabolites and embryo growth of primed tobacco (Nicotiana tabacum L. cv. ‘KFI09’) seeds were observed during priming. The seeds were primed at 15 and $25^{\circ}C$ for 1, 2, 3, 5, 10 and 15 days in a -0.8 MPa polyethylene glycol 6000 (PEG) solution. The time to 50% seed germination (T$_{50}$) was greatly reduced when the seeds were primed at $25^{\circ}C$ when compared with 15$^{\circ}C$. The $\alpha$-amylase activity and sugars and amino acid contents in the seeds primed at $25^{\circ}C$ greatly increased, while $\alpha$-amylase activity was similar, and sugar and amino acid contents increased slightly in the seeds primed at 15$^{\circ}C$. When the seeds were primed at $25^{\circ}C$, growth of the embryo which was enclosed by endosperm was detected, while the endosperm became thinner as the priming duration was extended.d.

• 한국작물학회지
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• 제44권3호
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• pp.263-266
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• 1999

Tobacco (Nicotiana tabacum L. ‘KF109’) seeds were primed in polyethylene glycol 6000 (PEG 6000) solutions to determine a) what osmotic potential of the solution would be optimal for priming, i.e., critical potential level for preventing germination, and b) what temperature and duration would be the most effective in priming. The germination was completely prevented below -0.8 MPa of PEG 6000, that indicates a optimum water potential for seed priming. Seeds were primed for 0, 1, 2, 3, 5, 10 and 15 days at 15, 20 and $25^{\circ}C$, respectively, under the-0.8 MPa PEG 6000 solution to find out the most effective temperature and duration for priming. The effectiveness of priming, particularly in germination speed, was observed more distinctly when the primed seeds were germinated at 15$^{\circ}C$ than 2 5$^{\circ}C$. The greatest reduction of the time to 50% germination (T/sob 50/) was when the seeds were primed at $25^{\circ}C$. The reduction rate of the $T_{50}$ was rapid when primed from 1 day to 8 days and then slowed down in the seeds primed for longer than 8 days. The time from 10 to 90% germination ( $T_{10-90}$ increased in the primed seeds for longer than 8 days which showed the reversed effect of synchronous germination. However, $T_{50}$ was reduced continuously in the seeds even primed over 8 days. Thus, the optimum condition for tobacco seeds priming with PEG 6000 solution was -0.8 MPa in osmotic potential of the solution at $25^{\circ}C$ for 8 days.ays.

• 접착 및 계면
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• 제10권4호
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• pp.155-161
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• 2009

최근 자동차용 도료의 가장 큰 관심 중에 한 가지는 도장공정을 줄여 생산성 및 환경친화성을 높이는 "compact coating process"이다. 그 중에서 pre-primed 도료는 기존의 전착도료와 primer 도료를 대체하는 도료로서 각광받고 있는 기술이다. 용접이 가능한 weldable pre-primed 도료에서 가장 중요한 물성은 유연성, 내식성, 용접성 등이다. 본 연구에서는 부착성과 유연성이 우수한 polyester resin, 이를 개량하여 유연성을 극대화한 elastomeric polyester resin을 합성하였고, 내구성과 물리적 성질이 우수한 polyvinyliedene fluoride resin을 합성한 후 경화거동 및 인장물성 등을 평가하였다. elastomeric polyester resin을 사용한 도료시스템이 유연성 및 부착성 측면을 고려했을 때, pre-primed 도료시스템에 적용하기에 가장 적합하였다.

• 대한미생물학회지
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• 제6권1호
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• pp.29-40
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• 1971

Various kinds of antibiotics are generally believed to have inhibitory effects on the antibody response. However, as polymyxin B which belongs to the cyclic polypeptide group of antibiotic was found to have some enhancing effects on the antibody response of rabbits to enterobacterial common antigen(CA) under specified conditions, experiments were carried out on this problem with the following results. 1. When mixture of polymyxin B and CA derived from Salmonella typhimurium(STM) was treated 30 minutes at $37^{\circ}C$ and injected three times into rabbits by intravenous route, the antibody response to CA was weaker than rabbits injected CA only. 2. Mixture of polymyxin B and CA showed a marked antibody production when injected into rabbits primed with small amounts of heat-extracted antigen of STM, while the injection of CA alone showed low titers of response. 3. Mixture of polymyxin B and heat-extracted CA-containing antigen of Escherichia coli 014 also showed a increased antibody production than CA alone in rabbits primed with antigen of STM. 4. The effect of polymyxin B appeared in different ways. This antibiotic did not enhance the CA antibody response in rabbits primed with small amounts of E. coli 0111 and 055, but enhance in rabbits primed with Shigella flexneri. 5. No enhancing effect on the antibody response was observed by polymyxin B in rabbits primed with CA. 6. No enhancing effect on the antibody response was also noted in rabbits primed with STM antigen in case polymyxin B and CA were administered simultaneously but in veins of different places. 7. Bacitracin did not enhance the CA antibody response in primed rabbits with STM antigen, but neomycin slightly enhance the response. 8. Lipopolysaccharide showed no priming effect on the CA antibody response, and no enhancement of the CA antibody response in rabbits printed with STM. 9. The priming effect of STM antigen against CA antibody response was very weak as compared with the effect of CA derived from STM antigen.