This study presents a rapid and quantitative sequential separation method for H-3 and C-14 isotopes with distillation apparatus in environmental samples released from nuclear facilities. After adding 200 mg of granulated potassium permanganate and 500 mg of sodium hydroxide in 100 mL of sample solution, the sample solution was heated until approximately 10 mL of distillate, and the distillate fraction was removed. The sample solution was heated again until a minimum 10 mL of additional distillate was collected. 10 mL of distillate was transferred to the LSC vail and the measurement sample for H-3 was made by adding 10 mL of Ultima Gold LLT to the LSC vial. After adding 2.5 g of potassium persulfate, 2 mL of 1M silver nitrate and 15 mL of concentrated nitric acid to the remained sample solution, the sample solution was heated for 90 minutes and C-14 isotopes were adsorbed into 10 mL of Carbo-Sorb solution in glass vial. The measurement sample for C-14 was made by adding 10 mL of Permafluor to the C-14 fraction in glass vial. The purified H-3 and C-14 samples were measured by the liquid scintillation counter after quenching correction. The average recoveries of H-3 and C-14 with CRM were measured to be 96% and 85%, respectively. The sequential separation method for H-3 and C-14 investigated in this study was applied to activated charcoal filter produced from nuclear power plants after validating the reliability by result of proficiency test (KOLAS-KRISS, PT-2021-51).
The dissemination process of agricultural research and development (R&D) results has somewhat different characteristics from that of typical R&D results. However, these characteristics are not adequately considered on the basis of an examination of the current performance system, the resulting management plans, and strategies for the application and dissemination of the results of agricultural R&D in Korea. The performance evaluation indicator exposed the problem of the inadequate consideration of the characteristics of each of these areas, particularly the lack of unified R&D-related institutions and the inadequacy of the system to monitor outcomes. To address these shortcomings in the agricultural R&D programs in Korea, the policies pertaining to agricultural R&D performance, results management, and dissemination in the U.S. and Japan were examined. Based on these investigations, we proposed strategies to improve the agricultural R&D policies in Korea.
Plant height of 'Composite 28' was 89㎝ and heading date was on 4 May with green leaf color and showed high yield among three composite lines. A visual score of winter field survival of 'Composite 28' was 1.0. 1st dry matter yield of 'Composite 28' in Cheonan was 8.64ton per ㏊ compared to introduced variety 'Amba'(7.20ton/㏊). Heading date of 'Composite 28' was 7 days earlier than check variety, 'Amba'.
To get good productivity and high feed value of forage, we develop to new Italian ryegrass (Lolium multiflorum Lam.) 'Kogreen'.variety. In Suwon, heading date of 'Kogreen' was on May 3 but in Yonchun was on 8 May that was 2 day later than that of 'Florida 80' and dry matter yield is 12.7ton/㏊, and had a good cold tolerance.
In the present study, genotypic variation of Agrobacterium-mediated transformation of Korean Italian ryegrass has been evaluated. Mature seed-derived calli of a total of seven cultivars were infected and co-cultured with Agrobacterium tumefaciens carrying the binary vector pCAMBIA1301, which contains a reporter gene (gus) and a plant selectable marker gene conferring resistance to hygromycin (hpt) in the T-DNA region. The effects of several factors such as callus type and callus age on transformation frequency and the expression of the GUS gene were investigated. The highest transformation frequency (6.7%) was obtained with the Hwasan 101 cultivar when 9-week-old calli (type-I) were inoculated with Agrobacterium. The overall transformation rates of the examined cultivars ranged from 0.4% to 6.7%. GUS histochemical assays, PCR, and southern analysis of transgenic plants demonstrated that transgenes were successfully integrated into the genome of Italian ryegrass. Thus, optimization of transformation frequency and selection of a suitable cultivar of Italian ryegrass may improve molecular breeding of this species.
In the present study, we have used an annealing-control-primer (ACP)-based differentially display RT-PCR method to identify salt-stress-induced differentially expressed genes (DEGs) in barley leaves. Using 120 ACPs, a total of 11 up-regulated genes were identified and sequenced. Temporal expression patterns of some up-regulated DEGs in response to salt stress were further analyzed by Northern blot analysis. The possible roles of these identified genes are discussed within the context of their putative role in response to salt stress. Thus, the identification of some novel genes-such as SnRK1-type protein kinase; 17 kDa, class I, small heat shock protein; and RNase S-like protein precursor genes-may offer a new avenue for better understanding the salt stress response in plants, knowledge which might be helpful for developing future strategies.
In this study, we conducted to select the promising crops for both uses in the bioethanol and forage production in Korea. The result indicated t㏊t Natsukaje (guinea grass), Gwangpyeongok (corn), Jumbo (sorghum×sudangrass hybrid), SS405 (sorghum×sorghum hybrid), Millex32 (pearl millet), Jeju barnyard grass), Alamo (switch grass) and Selection75 (klein grass) showed the production of biomass from the highest to the lowest in order. However, the order of the production of quality forage was, from the highest to the lowest, Natsukaje (guinea grass), Jumbo (sorghum×sudangrass hybrid), SS405 (sorghum×sorghum hybrid), Gwangpyeongok (corn), Millex32 (pearl millet), Selection75 (klein grass), Jeju (barnyard grass), and Alamo (switch grass). We concluded the Natsukaje (guinea grass) was the best bioethanol crop, and also the Natsukaje (guinea grass) was the best for forage production.
To know adaptability and production of silage corn, we studied on paddy field experiment. Heading date of 'Kwangpyongok' and 'P32P75' Hybrids was on 15th July, 14th July respectively. The dry matter yield of 'P32P75' hybrid (20.4ton/㏊) was the highest among 10 hybrids and that of 'Kwangpyongok' hybrid (19.1ton/㏊) showed high in domestic corn hybrids and other characters as like feed vales is almost same in 10 hybrids.
2가지 이상의 채질로 결합된 구조물이 온도 변화를 받으면 열웅력이 발생한다. 이러한 웅력은 재질간의 열
팽창계수가 서로 상이하여 생긴다. 본 논문에서는 균일한 용도변화를 받는 복합 재료로 이루어진 축대칭 원판
(disk) 에 대한 웅력상태를 구하는 공식올 유도하였다. 먼저, 재료역학원리를 이용하여 근사해를 구한 후,
Eigenfunction series를 전개하여 탄성학적인 정확해(Exact Solution) 를 구하였다. 또한 정확해는 유한요소
법으로 구한 해와 비교하였다. 상기 근사해로는 연계연에서의 웅력분포를 예측하는 데 어려움이 있었으나, 정
확해는 유한요소법으로 구한 결과와 대체로 일치하고 있어 웅력분포를 충분히 예측할 수 있었다. 따라서, 본
논문에서 구한 정확해 (Exact Solution) 공식은 복합재료로 구성된 구조물의 연계변에서의 응력분포를 결정
하는데 유용하다.