검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 121

        1.
        2022.05 구독 인증기관·개인회원 무료
        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).
        2.
        2022.05 구독 인증기관·개인회원 무료
        To obtain the gamma-ray energy spectrum of artificial radionuclides which is difficult to obtain practically, virtual gamma-ray energy spectrum simulator program was developed. It can be applied for the predetermined measurement condition for which the database was developed through computational simulation and actual measurement of background radiation. For gamma spectrometry training for KHNP HPGe detectors using this program, the database for KNPG HPGe detectors was developed. First, the geometry of the detector in the simulation was adjusted to resemble the real structure by comparing the actually measured net counts rate at the main gamma peak with the value simulated by MCNP6. The Certified Reference material (CRM) of 137Cs and 60Co were used for verification. The comparison was made with respect to the situation where CRM was attached to the top and side of the detection part of the considered detector. The geometry structures of detectors were simulated by reflecting the design drawing of the products, and the simulation was performed for several thicknesses of the Ge/Li dead layer in consideration of the change in the thickness over time. As the results, the simulation geometry was tuned so that the results for 137Cs showed a difference within 10% for all detectors. At this time, in some detectors, the result for 60Co shows a 10% higher error, which is estimated to be due to the random summing. It was not considered in tuning the simulation geometry, but it was found that improvements were needed to reflect the coincidence summing when construction the virtual spectrum in the future. The determined simulation geometry was applied to generate theoretical gamma-ray energy spectra of representative artificial radionuclides. In order to create a virtual spectrum similar to the real one, the background spectrum was measured for each detector without a source, and the simulation results were calculated in the form of having the same energy channel as the background spectrum. The background spectrum and theoretical spectra of artificial radionuclides for each detector were databased so that virtual spectra could be generated under desired conditions. The virtual spectrum was generated by adding a background spectrum and a spectrum obtained by multiplying the spectrum of the desired nuclide by the concentration of the nuclide. The validity of generated virtual spectra was verified using the pre-developed gamma spectrometry program. As a results of gamma spectrometry of virtual spectra, the virtual spectra was verified by showing a difference within 20% from the radioactivity value input when generating the virtual spectra.
        10.
        2020.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        충청북도농업기술원에서는 분홍색의 향기가 있고, Dendrobium kingianum에 비해 왜성종이며, 2월 하순경 개화하는 덴드로비 움 ‘리틀핑크’(D. kingianum ‘Little Pink’)를 육성하였다. 신품종 ‘리틀핑크’는 2007년 D. kingianum을 모본으로, D. kingianum var. silcockii를 부본으로 교배하였다. 종자 발아, 재배, 선발, 특성검정은 2008년부터 2015년까지 진행되었다. 생육이 좋고 꽃의 색, 모양이 우수한 계통을 선발한 후, 2016년부터 2018년까 지 3년에 걸쳐 국립종자원 신품종 심사기준으로 특성검정 결과, 우수성이 인정되어 2019년 최종 선발하여 ‘리틀핑크’로 명명하 였다. 주요 특성은 다음과 같다. 화색은 분홍색으로 Red-purple Group 72B(RHS color chart)이며, 향기가 있고 꽃잎무늬는 농담 무늬이다. 식물체 크기는 7.3cm로 대조품종 D. kingianum 23.5cm에 비해 작은 왜성종이다. 엽의 폭은 1.2cm이고, 꽃의 넓이는 2.4cm이다. 소화수는 3.7개이고 전반적으로 화분의 볼 륨감이 좋은 편이다. 꽃자루 길이는 7 .2cm로 대조품종 D. kingianum에 비해 짧다. 개화기는 2월 하순이며, 개화기간은 30일 정도이다.
        4,000원
        12.
        2019.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        충청북도농업기술원에서는 연한 분홍색의 향기가 있고, 꽃수가 많으며, 개화기간을 오래 지속할 수 있는 속간 교배종 난 ‘핑키뷰티’를 육성하였다. 신품종 ‘핑키뷰티’는 2007년 Phal. pulcherrima × Phal. parishii 교배종을 모본으로, Neof. falcata ‘Hwacheon’을 부본으로, 속간교배하였다. 종자 발아, 재배, 선발, 특성검정은 2008년부터 2014년까지 진행되었다. 생육이 좋고 꽃의 색, 모양이 우수한 계통을 선발 한후, 2015년부터 2017년까지 3년에 걸쳐 국립종자원 신품종 심사기준으로 특성검정 결과, 우수성이 인정되어 2018년 최종 선발하여 “핑키뷰티”로 명명하였다. 주요 특성은 다음과 같다. 화색은 연분홍색으로 Red-purple Group 68D(RHS칼라차트)이며, 향기가 있고 화경색은 암록색이다. 식물체 크기는 12.7cm로 대조품종과 큰 차이를 보이지 않았다. 잎의 폭은 1.6cm로 대조품종인 P. pulcherrima에 비해 좁은 편이다. 화경장은 25.8 cm이며, 소화수는 16.3개로, 전반적으로 화분의 볼륨감이 우수한 편이다. 꽃의 크기는 2.5cm 정도이며, 꽃의 순판 뒤쪽에 풍란과 같은 짧은 거가 있는 것이 특징이다. 개화기는 5월 하순이며, 개화기간은 34일 정도이다.
        4,000원
        13.
        2019.06 구독 인증기관 무료, 개인회원 유료
        The bacterial diversity of an Antarctic hard coral, Errina fissurata, was examined by isolating bacterial colonies from crushed coral tissue and by sequencing their 16S rRNA gene. From the analyzed results, the bacteria were classified as Actinobacteria (56%), Firmicutes (35%) and Proteobacteria (9%). The thirty-four isolates were cultured in liquid media at different temperatures and their growth was assessed over time. The majority of the isolates displayed their highest growth rate at 25℃ during the first three days of cultivation, even though the coral was from a cold environment. Nevertheless, strains showing their highest growth rate at low temperatures (15℃ and 4℃) were also found. This study reports the composition of an Antarctic hard coral-associated culturable bacterial community and their growth behavior at different temperatures.
        4,000원
        14.
        2018.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to improve growth performance of Hanwoo heifer and to produce high quality of meat with dietary means during growing and early fattening period. Particularly, additional energy diet to relieve estrus stress was main purpose in this study. The results of in vitro rumen fermentation indicated that there was no negative effect by additional energy diet as treatments. In the feeding trial, twenty Hanwoo heifers(average 10 months age) were allocated and distributed into two treatments in randomized block design based on body weight. There were three growth stages such as growing, early fattening and late fattening periods in this feeding program, respectively. In growing stage, there were two treatments consisting of only total mixed ration(TMR) as a control and TMR with additional energy treatment. The experimental diets were fed twice a day, and water and mineral were freely accessed. In additional energy treatment, 500 g of concentrate diet was fed daily to relieve estrus stress due to obese with high energy intake. Not outstandingly differences were found across the treatments during entiretrial period. While, unexpectedly greater feed conversion ratio in treatment compared to the control was found during late fattening period. It seems that the blood cortisol decreased with addition energy supplementation compared with the control during trail period. Carcass characteristics including carcass weight, back fat thickness, marbling score, meat color, fat color, maturity and texture were not significantly different each other. Rib-eye area, however, was greater in the control compared to the treatment(p<0.05). In addition, it appears that yield index was tended to be greater in the control. In conclusion, it is suggested that additional energy supplementation to Hanwoo heifer could get a potential in improving meat quality and relieving estrus stress.
        4,000원
        15.
        2018.10 구독 인증기관·개인회원 무료
        Hermetia illucens is one of many of solider flies and the species was decomposing ability to food waste, livestock feces and so on. Specially, the study was conducted to investigated of artificial feeding using the livestock feces, because of easy to get and see in a rural areas. But, comparing food waste with livestock feces, the growth character of H. illucens was generally small size and the growth period is longer than feeding food waste. In order this problem, the experiment was performed by mixing sugar 1%, 5%, 10%, 20% , which can accelerate the degradation of the pig and cattle feces during the 0, 3, 5, 7 days. As a result, when the width and length of H. illucens were compared by sugar mixing and fermentation period, they was no significant difference. Decomposing ability of a larvae were 0.44g with cattle feces+sugar 5% than 20% and were 0.64g with pig feces+sugar 20% than 5%.
        16.
        2018.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        하늘매발톱꽃(Aguilegia flabellata var. pumila K.) 육묘시 적정 용토종류 및 시비 수준을 구명코자, 용토종류는 원예용 상토, 피트모스, 밭흙, 원예용상토 + 피트모스(1:1, v/v), 원예용상토 + 밭흙(1:1, v/v), 밭흙 + 피트모스(1:1, v/v), 밭흙 + 퇴비(1:1, v/v), 원예용상토 + 피트모스 + 밭흙(1:1:1, v/v/v) 혼합용토를 사용하였으며, 시비 시험은 기준시비량을 질소 – 인산 – 칼리 = 12 – 9 – 12kg/10a(초화류 표준시비량)을 기준으로 하여 기준시비량 대비 0%, 50%, 75%, 100%, 125% 및 150%를 처리하여 시험한 결과, 용토종류는 용토별 화학적 특성은 피트모스가 pH 및 양분함량이 가장 낮았고, 원예용 상토 및 퇴비가 혼합된 용토에서 EC를 비롯한 양분함량이 높은 경향이었다. 발아율은 피트모스 단용 처리에서 파종 30일 및 45일에 각각 48% 및 54%로 가장 낮았고, 밭흙 + 퇴비 혼합용토에서는 86%였고, 그 외 용토에서는 92~98%였다. 파종 후 120일과 150일의 묘생육은 원예용상토에서 가장 좋았다. 시비량별 생육은 무처리에 비하여 시비 처리구에서 생육이 좋았으며, 식재 100일 후 생육에서는 기준 시비량 75%, 100% 및 125%에서 양호한 경향을 보였다. 기준 시비량 150% 처리에서는 오히려 생육이 감소하는 경향이었다. 결과적으로 하늘매발톱꽃 육묘시 육묘용토에서는 원예상토를 이용하고 시비기준은 기준시비량 대비 75%로 관리하는 것이 전반적인 생육이 양호하였다.
        4,000원
        18.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Examining the experiences of seven preservice teachers enrolled in a materials development class, this qualitative case study aimed to explore the way their participation in the materials development process was connected not only to their increased knowledge of and skills in materials development but also to their self-perceived confidence as prospective teachers, contributing to their professional development. The data were collected from multiple reflection papers and were analyzed qualitatively. The findings demonstrated that the materials development class offered the preservice teachers an opportunity to gain insight into the importance of materials in language education and of teachers being knowledgeable and skilled in materials design and development. They also came to a new realization that teachers were active agents who could take initiatives in adapting and developing materials, rather than passive users following the prescribed textbooks. The materials development class further taught them the need to prioritize the goal of promoting successful language learning when developing materials and to take a critical approach in order to counteract any biased cultural representations and their negative consequences on students’ worldviews. Gaining confidence, the preservice teachers spoke highly of their experiential learning in the class as they thought the experience prepared them to become more competent teachers.
        6,700원
        19.
        2016.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Composite resins are developed as restorative materials to improve esthetics and mechanical properties. To improve the physical properties of resin material, resin filler have to be added. However, no imaging method is adopted for resin filler distribution. Optical coherence tomography (OCT) is a optical imaging technique to delineate microscopic structures within biological tissue. The OCT application to dental composites resin and its filler is not described yet. So, this new and advanced optical method is needed for clinical application for evaluation of dental composite resin. To analyze the spatial distribution of dental composite resin and to evaluate the resin restoration in cavity, frequency domain optical coherence tomography (FD-OCT) was used for their analysis. Resin restored tooth was prepared. For morphological observation, serially sectioned teeth, conventional X-ray taking and micro computed-tomography (CT) images were compared with OCT images. The experiment has done to evaluate the success of the resin restoration using 3 dimensional structure OCT image. In this research, OCT is evaluated as a new technique to image resin restoration. The evaluation of resin restored tooth was performed by OCT. Inappropriate restoration such as marginal adaptation, large porosities, internal integrity and poor contour could be detected. Resin filler also could be checked by OCT. The distribution, number, regularity and size of resin filler can be differentiated from several commercial products. Considering the characteristics of the OCT, it can be used to evaluate the defects of resin restoration, resin filler distribution, and internal integrity between resin material and tooth structure. The OCT can be considered to be a new and advanced method for the evaluation of resin restorations.
        4,000원
        1 2 3 4 5