• Journal of Radiation Protection and Research
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• 제24권2호
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• pp.55-63
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• 1999

우리 국토의 방사선환경을 이해하고 사고에 대비한 베이스라인 데이타를 축적하기 위하여 전국 33 지역의 논과 밭에서 15 cm 깊이로 토양을 채취하고 $\gamma$-스펙트로메트리법으로 $^{137}Cs$ 농도를 측정하였다. 토양중 $^{137}Cs$의 농도는 논에서는 $0.7{\sim}17.7$ Bq/kg-dry, 밭에서는 $1.2{\sim}27.8$ Bq/kg-dry의 범위로 평균은 각각 6.9 Bq/kg-dry 및 9.9 Bq/kg-dry였다. 토양중 $^{137}Cs$의 농도는 논에서는 유기물 함량과 정의 상관이, 점토 함량과는 부의 상관이 있었고 밭에서는 양이온치환용량과 정의 상관이 있었다. 토양 유기물이 경작지 토양중 $^{137}Cs$의 농도변화에 중요한 역할을 하는 것으로 드러났다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권3호
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• pp.375-381
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• 2012

Two experiments were conducted to establish a digestible energy (DE) content prediction model of rapeseed meal for growing-finishing pig based on rapeseed meal's chemical composition. In experiment 1, observed linear relationships between the determined DE content of 22 rapeseed meal calibration samples and proximate nutrients, gross energy (GE) and neutral detergent fiber (NDF) were used to develop the DE prediction model. In experiment 2, 4 samples of rapeseed meal selected at random from the primary rapeseed growing regions of China were used for testing the accuracy of DE prediction models. The results indicated that the DE was negatively correlated with NDF (r = -0.86) and acid detergent fiber (ADF) (r = -0.73) contents, and moderately correlated with gross energy (GE; r = 0.56) content in rapeseed meal calibration samples. In contrast, no significant correlations were found for crude protein, ether extract, crude fiber and ash contents. According to the regression analysis, NDF or both NDF and GE were found to be useful for the DE prediction models. Two prediction models: DE = 16.775-0.147${\times}$NDF ($R^2$ = 0.73) and DE = 11.848-0.131${\times}$NDF+0.231${\times}$GE ($R^2$ = 0.76) were obtained. The maximum absolute difference between the in vivo DE determinations and the predicted DE values was 0.62 MJ/kg and the relative difference was 5.21%. Therefore, it was concluded that, for growing-finishing pigs, these two prediction models could be used to predict the DE content of rapeseed meal with acceptable accuracy.

• Applied Biological Chemistry
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• 제31권2호
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• pp.147-153
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• 1988

마늘의 품질보존을 위한 수단으로서 전리에너지인 장마선의 이응이 가능해짐에 따라, 발아억제 선량인 0.1kGy 처리와 저장조건$(3{\pm}1^{\circ}C,\;75{\sim}85%\;R.H.;\;12{\pm}5^{\circ}C,\;75{\sim}85%\;R.H.)$이 마늘의 몇가지 성분변화에 미치는 영향을 조사하였다. 0.1kGy의 감마선 조사는 시료의 수분함량에 거의 영향을 미치지 않았으나 실온저장 10개월 후의 대조시료는 조사시료에 비해 수분함량이 유의적으로 감소되었다(P<0.05). 발아억제 처리는 저장중 시료의 총당 함량의 변화를 완만하게 하였으며, 저온저장 8개월 후 대조시료의 유리당 함량은 조사시료에 비해 유의적으로 증가되었다. 발아억제 선량의 감마선 처리는 시료의 아스코르브산과 지방산 참량에 거의 영향을 주지 않았으나 아미노산 조성중 글루탐산과 아스파르트산 함량에는 영향을 미치는 것으로 나타났다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2022년도 추계학술대회
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• pp.23-23
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• 2022

Rapeseed (Brassica napus L.) is one of the most valuable oilseed crop in the world. It is widely used in various industries, such as food, animal feed, energy and chemical industries. In order to improve the industrial requirements for rapeseed, useful agronomic characteristics (higher yields and disease resistance etc.) and modified oil traits (fatty acid composition and fat content) are important in rapeseed. However, Korea has limiting genetic resources of novel traits in rapeseed. In this research, novel rapeseed mutant genotypes by mutation breeding was developed. The mutant lines were generated by the treatment of the seeds of the original cultivar 'Tamra' with 700 Gy of gamma-ray (⁶⁰Co). Mutants showing varied in flowering time, crude fat content, seed yield and fatty acid content that exhibited stable inheritance of the mutated characteristics from M₅ to M₇ generations were selected. We investigated genetic variation using SNPs identified from GBS analysis in rapeseed mutant lines derived from the gamma-ray, and interactions between the major agronomic and the oil traits. Significantly associated SNP loci were explored along with candidate genes using SNPs obtained by GBS analysis. As a results of association mapping, a total of 322 SNPs were significantly associated with agronomic traits (155 SNPs) and oil traits (167 SNPs). A total of 70 genes were annotated from agronomic characteristics SNPs; among them 7 genes significantly enriched in developmental process, and a total of 70 genes were annotated from crude fat content and fatty acid compositions SNPs; among them, 11genes were significantly enriched in biosynthetic process. These results could be used for the selection of rapeseed cultivar with enhanced qualities and potential economic benefits.

• 분석과학
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• 제37권4호
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• pp.251-260
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• 2024

As polymers became very important in our lives, their negative impact on general health and the environment raised a serious issue. Here, enhancing their life term is presented as a compromise solution between the need and harm. In the study, six PVC films, the plain and five filled with improvers, underwent radiation exposure for 300 hours at room temperature to investigate their photodegradation rates. The modified films were embedded with organotin(IV) complex derivatives (Ph₃SnL, Ph₂SnL₂, Bu₃SnL, Bu₂SnL₂, and Me₂SnL₂ (where L is levofloxacin)), and their effectiveness was evaluated. The PVC films were compared before and after exposure to various tests including UV-Vis spectroscopy, gel content analysis, theoretical calculations, and EDX microscopy. Findings indicated that the presence of organotin(IV) complex derivatives, particularly Ph3SnL, notably decreased UV light absorbance and the amount of gel content in PVC sheets in comparison to untreated PVC. Furthermore, EDX analysis showed that the PVC-Ph₃SnL blend exposed to radiation exhibited the highest chlorine content, reaching 30 %. This blend demonstrated superior efficacy in stabilizing the polymeric materials.

• Journal of Biosystems Engineering
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• 제27권1호
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• pp.51-58
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• 2002

The goal of this research was to an optimum conditions for the brown rice conditioning from data of milling characteristics after conditioning of the brown rice. The range of the initial moisture content of the sample was 13%, 14%, and 15%, the range of the increment of the moisture content was 0.4% and 0.8% with respect to the initial moisture content, and a ripe time after conditioning was eight hours. The results obtained from this research can be summarized as fellows. 1 The crack ratio after conditioning the brown rice with the initial moisture content was increased as the initial moisture content decreased and increment of the moisture content increased. The crack ratio of the milled rice was increased than that of the non-conditioned brown rice and decreased with the conditioned brown rice with the increment of the moisture content of 0.4% and 0.5%. 2. The broken rice ratio after conditioning the brown rice with the initial moisture content was a little higher than that of the non-conditioned brawn rice. The broken ratio of the conditioned brown rice with the increment of the moisture content of 0.4% was increased around 0.2∼0.4% with respect to the non-conditioned brown riced and the broken ratio of the brown rice was high with increased amount of water sprayed during conditioning process. 3. The moisture content of the milled rice after conditioning the brown rice with the initial moisture content increased around 0.3∼0.8% with respect to the non-conditioned milled rice. 4. The electric energy consumption on milling process with the conditioned brown rice by the initial moisture content was decreased 3.4∼39.1% with respect to the non-conditioned brown rice.

• 한국세라믹학회지
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• 제44권3호
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• pp.162-168
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• 2007

Silica wet gels were prepared ken water glass ($29\;wt%\;SiO_{2}$) by using Amberlite as a ion exchange resin. After washing in distilled water, the wet gels were further aged in a solution of TEOS/EtOH to strengthen of 3-dimensional network structure. As increase TEOS content in aging solution, BET surface area and porosity of the ambient dried silica aerogels were significantly decreased, and average pore diameter was also decreased 30 nm to -10 nm. Also, higher density and compressive strength were obtained in case of higher TEOS content. This is due to precipitation of $SiO_{2}$ nano particles by TEOS. Hence, TEOS addition plays an important role of both strengthening and stiffness of silica wet gel network. By adding over 30 vol% TEOS, a crack-free monolithic silica aerogel tiles were obtained and its density, compressive strength, and thermal conductivity were shown $0.232g/cm^{3}$, 7.3 MPa, and 0.029 W/mk, respectivly.

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1494-1502
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• 2013

Energy flow and C-$H_{methyl}$ and C-$H_{ring}$ bond dissociations in vibrationally excited toluene in the collision with $N_2$ and $O_2$ have been studied by use of classical trajectory procedures. The energy lost by the vibrationally excited toluene upon collision is not large and it increases slowly with increasing total vibrational energy content between 5,000 and 45,000 $cm^{-1}$. Intermolecular energy transfer occurs via both of V-T and V-V transfers. Both of V-T and V-V transfers increase as the total vibrational energy of toluene increases. When the total energy content $E_T$ of toluene is sufficiently high, either C-H bond can dissociate. The C-$H_{methyl}$ dissociation probability is higher than the C-$H_{ring}$ dissociation probability, and that in the collision with $N_2$ is larger than with $O_2$.

• Structural Engineering and Mechanics
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• 제90권5호
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• pp.493-504
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• 2024

This paper presents the methodology and results for the investigation of the structural safety of 40 aged underground water tanks to support the weight of photovoltaic (PV) systems that were supposed to be placed on their roof reinforced concrete (RC) slabs. The investigation procedure included (1) review of available documents; (2) visual inspection of the roof RC slabs; (3) carrying out a series of nondestructive (ND) tests; and (4) analysis of results. Out of the 40 tanks, eleven failed the visual inspection phase and were discarded from further investigation. The roof RC slabs of the tanks that passed the visual inspection were subjected to a series of ND tests that included infrared thermography, impact echo, ultrasonic pulse velocity (UPV), Schmidt hammer, concrete core compressive strength, and water-soluble chloride content. The NDT results proved that eight more tanks were not suitable to support the PV systems. Based on the results of the visual inspection and testing, a probabilistic decision-making criterion was established to reach a decision regarding the structural integrity of the roof slabs. The study concluded that the condition of the drainage filter was essential in protecting the tanks and its intact presence can be used as a strong indication of the structural integrity of the roof RC slabs.

• Journal of the Korean Wood Science and Technology
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• 제34권4호
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• pp.54-65
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• 2006

본 연구는 우리나라의 남부 지방인 전남 광양의 백운산 지역(해발 800 m)에서 자라는 60~70년생 신갈나무림과 제주 한라산 지역(해발 1,000 m)에서 자라는 60년생 신갈나무림의 바이오매스와 에너지 고정량을 추정하기 위해 각 지역별로 5~9 본씩 총 25 본의 표본목을 조사하였다. 광양 백운산 지역 북사면 신갈나무림의 바이오매스 현존량은 288.4 ton/ha, 남사면은 241.9 ton/ha이었으며, 제주 한라산 지역 북사면은 368.4 ton/ha, 남사면은 364.3 ton/ha로 나타났다. 또한 연간 순생산량은 백운산 지역 북사면 20.7 ton/ha/yr, 남사면 17.7 ton/ha/yr이었다. 한라산 지역 북사면은 19.0 ton/ha/yr, 남사면 21.2 ton/ha/yr로서 바이오매스 현존량과 연간 순생산량 모두 한라산 지역이 백운산 지역보다 더 높게 나타났다. 그러나 잎의 생산 효율인 순동화율(NAR)은 백운산 지역(4.1~5.1)이 한라산 지역(3.7~4.6)보다 더 높게 나타났다. 한편, 광양 백운산 지역에서 북사면 신갈나무림의 에너지 현존량은 5,666 GJ/ha, 남사면은 4,793 GJ/ha이었으며, 제주 한라산 지역에서 북사면은 6,550 GJ/ha, 남사면은 6,435 GJ/ha로 나타났다. 연간 에너지 고정량은 백운산 지역 북사면 365 GJ/ha/yr, 남사면 360 GJ/ha/yr, 한라산 지역 북사면 351 GJ/ha/yr, 남사면 347 GJ/ha/yr로서 백운산 지역이 한라산 지역보다 더 높은 것으로 나타났다.