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Correlation between physicochemical properties and biological half-life of triazole fungicides in perilla leaf (들깻잎에서 Triazole계 살균제의 생물학적 반감기와 물리화학적 특성과의 상관관계)

  • Lee, Sang-Hyeob;Kwak, Se-Yeon;Hwang, Jeong-In;Kim, Hyo-Jung;Kim, Tae-Hwa;Kim, Jang-Eok
    • Journal of Applied Biological Chemistry
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    • v.62 no.4
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    • pp.407-415
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    • 2019
  • The biological half-life of pesticides applied on crops is the key indicator for ensuring the safety of agricultural products. The biological half-life is affected by the several factors like growing conditions of the crop, climate, application method, and physicochemical properties of pesticides. In this study, the biological half-life was calculated and the degradation rates of six triazole fungicides sprayed on perilla leaves were evaluated. Moreover, the statistical analysis confirmed the correlation between the biological half-life and physicochemical properties of six triazole pesticides. The recoveries of the six pesticides were between 84.8-104.9%, which satisfied the residual pesticide analysis criteria. The biological half-life of six pesticides sprayed on perilla leaves, calculated using the first-order kinetics model, ranged between 6.4-15.1 days. When the biological half-life and the physicochemical properties were correlated using the principal component analysis: pKa and Log P, the biological half-life was found to be affected by PC1. The correlation coefficient between biological half-life and physicochemical properties (pKa), calculated by Spearman rank-order correlation, was R2 = -0.928 (p <0.01). Biological half-life has been shown to correlate with pKa. In conclusion, it can be used as a database for the relationship between biological half-life and physicochemical properties and will contribute to ensure safe supply of agricultural products.

Sorption Characteristics of Strontium and Nickel on Mackinawite According to pH Variations in Alkaline Conditions (염기 환경에서 pH 변화에 따른 맥키나와이트 광물에 스트론튬과 니켈의 수착 특성)

  • Park, Chung-Kyun;Park, Tae-Jin;Lee, Seung-Yup;Lee, Jae-Kwang
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.1
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    • pp.73-81
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    • 2020
  • Strontium (90Sr) and nickel (59Ni) have been considered as key radionuclides in the safety assessment of radioactive waste disposal. Through various efforts to impede the migration of radioactive nuclides underground, it has been established that some minerals generated from the corrosion of the waste containers have a positive chemical interaction with these radionuclides. Among these minerals we selected mackinawite (FeS), an iron and sulfur compound, and performed a sorption experiment for the Sr and Ni in FeS under anoxic and alkaline conditions by reflecting deep underground environments. The effects of pH on sorption were likewise investigated in the pH range of 8 ~ 12. As a result, it was found that strontium failed to exhibit a good sorption capacity in a weak alkaline range, while nickel showed a noticeably higher sorption affinity over the entire experimental pH range. Moreover, we determined that as the pH increased in the solution, the distribution coefficients (Kd) were increased for both nuclides, which reflects when an alkalinity increses, the surface of the mineral charges much negatively by detaching the hydrogen or cations on the mineral surface. Thus, it can be concluded that the cationic nuclides of Sr and Ni can attach easily to the mineral under strong alkalinity.

Analysis on the Emersion and Submersion Patterns of the Coastal Zone in Korea (한국 연안의 노출 및 침수 양상 분석)

  • Ko, Dong Hui;Jeong, Shin Taek;Cho, Hong-Yeon
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.28 no.5
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    • pp.312-317
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    • 2016
  • The submersion and emersion patterns are key factors that directly influence the habitat environment of the coastal plants and animals. In this study, the coasts are divided into five zones (zones 1, 2, 3, 4, and 5 - not flooded, flooded once, flooded and exposed to air twice, exposed to air once, continuously flooded in the day, respectively) based on the patterns using tidal elevation data at the major eight stations and the domestic and international reference tidal levels, i.e., AHHW, ALLW, HAT and LAT, are also estimated to analyse the characteristics of the five distinct zones. Based on the results, the frequency of the zone 3 are dominant and forms from 87.2% to 88.2% (nearly constant) irrelevant with the tidal ranges at all stations. The taking-up percentages of the zones 2 and 4 show nearly constant, below 4% and over 8%, respectively. In Pohang station classified as the mainly diurnal tide, the percentages are decreased to 1.4% in zone 2 and increased to 10.8% due to the effects of the annual and semi-annual tidal components.

Study on Adsorption Features of Arsenic onto Lepidocrocite (레피도크로사이트(lepidocrocite) 표면의 비소 흡착 특성 규명)

  • Lee, Woo-Chun;Jeong, Hyeon-Su;Kim, Ju-Yong;Kim, Soon-Oh
    • Economic and Environmental Geology
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    • v.42 no.2
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    • pp.95-105
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    • 2009
  • Systematic studies are performed for arsenic adsorption on synthesized lepidocrocite. The synthesized lepidocrocite with high surface area of $94.8\;g/m^2$ has shown that the point of zero charge(PZC) is 6.57 determined by potentiometric titration, suggestive of high capacity of arsenic removal. Results show that arsenite[As(III)] uptake by synthesized lepidocrocite is greater than that of arsenate[As(V)] at pH $2{\sim}12$, indicating that the lepidocrocite has high affinity toward arsenite rather than arsenate. Adsorption of arsenate decreases with increasing pH from 2 to 12, whereas arsenite sorption increases until pH 8.0, and then decreases dramatically with increasing pH, suggesting that changes in surface charge of the lepidocrocite as a function of pH playa important role in aresinc uptake by the lepidocrocite. Upon kinetic experiments, our results demonstrate that both arsenite and arsenate sorption on the lepidocrocite increases rapidly for the first 4 h followed by little changes during the duration of the experiment, showing that adsorption plays a key role in aresenic uptake by the lepidocrocite. Our results also show that power function and elovich models are the best fit for the adsorption kinetics of arsenite and aesenate on the lepidocrocite.

Design for Database of Technical Data Configuration Management System (도면(圖面) 명세관리(明細管理)를 위한 데이터베이스 설계(設計))

  • Kim, Jae-Su
    • Journal of Information Management
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    • v.19 no.1
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    • pp.50-72
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    • 1988
  • The data base is a basis for the Management Information Systems (MIS) and Technical Data Packages(TDPs) are one of the key factors in the research and development activities. Most research institutes has been developed their own MIS and also MIS for the IDP has been advanced and applied in the various area. However, MIS and it's operation of the drawings and TDPs generated from researches and developments should be developed further more. In this study, we studied on the creation of data base of MIS related to the drawings, specifications and TDPs based on general concepts and priciple of MIS and data base. And finally, mentioned a design of data base consisting of drawing, specifications and related TDPs which are applied to MIS. To help to understand this system, it is presented, that three master files and six variable files were created, as a experimental data base, according to the "TOTAL" of CYBER computer system and two other user programs and it's outputs after computer run. It is expected that results of this study could be useful for TDP MIS enhancement through improvement of this study and new user program development.

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Analysis on Power Consumption Characteristics of SHA-3 Candidates and Low-Power Architecture (SHA-3 해쉬함수 소비전력 특성 분석 및 저전력 구조 기법)

  • Kim, Sung-Ho;Cho, Sung-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.1
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    • pp.115-125
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    • 2011
  • Cryptographic hash functions are also called one-way functions and they ensure the integrity of communication data and command by detecting or blocking forgery. Also hash functions can be used with other security protocols for signature, authentication, and key distribution. The SHA-1 was widely used until it was found to be cryptographically broken by Wang, et. al, 2005. For this reason, NIST launched the SHA-3 competition in November 2007 to develop new secure hash function by 2012. Many SHA-3 hash functions were proposed and currently in review process. To choose new SHA-3 hash function among the proposed hash functions, there have been many efforts to analyze the cryptographic secureness, hardware/software characteristics on each proposed one. However there are few research efforts on the SHA-3 from the point of power consumption, which is a crucial metric on hardware module. In this paper, we analyze the power consumption characteristics of the SHA-3 hash functions when they are made in the form of ASIC hardware module. Also we propose power efficient hardware architecture on Luffa, which is strong candidate as a new SHA-3 hash function. Our proposed low power architecture for Luffa achieves 10% less power consumption than previous Luffa hardware architecture.

Development of Separation and Trace Analysis Methods for Platinum Group Elements-Separation and Retention Behavior of Platinoid Metal Acetylacetonates in Reversed-Phase Liquid Chromatography (백금족 원소의 분리 및 미량분석법 개발에 관한 연구: 역상 액체 크로마토그래피에 의한 백금족 금속-아세틸아세톤 킬레이트들의 분리 및 머무름 거동)

  • Lee, Dai Woon;Kim, Kyung Soo;Park, Young Hun;Czea, Myoung Zoon;Chung, Koo Soon
    • Analytical Science and Technology
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    • v.6 no.1
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    • pp.107-119
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    • 1993
  • The purpose of this study is to investigated the elution behavior of platinoid metal acetylacetonates, which is the key to elucidate their retention mechanism and optimize their RPLC separation conditions. The retention data of four platinoid metal acetylacetonates have been measured on four different columns in methanol-water and acetonitrile-water systems. The retention of uncharged platinoid metal acetylacetonates is interpreted by solvophobic effect. The retention of platinoid metal acetylacetonates is also greatly influenced by the geometric structure of the complexes. The square planar chelates, $Pd(acac)_2$, $Pt(acac)_2$, are retained longer than the octahedral chelates, $Rh(acac)_3$, $Ir(acac)_3$. It is likely due to that square planar chelates show greater interaction with nonpolar stationary phase than octahedral chelates. The results of van't Hoff plots have shown that platinoid metal acetylacetonates is operated on the same retention mechanism in the temperature range of $25{\sim}45^{\circ}C$. The study of the retention mechanism by the enthalpy-entropy compensation phenomenon has indicated that the retention mechanism of octahedral chelates and square planar chelates do not vary with the composition change of methanol-water mobile phase, respectively. In acetonitrile-water mobile phase, however, the retention mechanism is observed to be more complicated. Optimum condition for the separation of four platinoid metal acetylacetonates is found to be 40% methanol, polymeric C18 column, and $45^{\circ}C$.

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An Efficient Broadcast Encryption System with Delegation of Decryption (복호화 위임을 제공하는 효율적인 브로드캐스트 암호시스템)

  • Han, Su Min;Park, Seung Hwan;Park, Jong Hwan;Lee, Dong Hoon
    • Journal of Broadcast Engineering
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    • v.18 no.5
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    • pp.758-770
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    • 2013
  • In a Broadcast Encryption System, a sender sends an encrypted message to a large set of receivers at once over an insecure channel and it enables only users in a target set to decrypt the message with their private keys. In 2005, Boneh et al. proposed a fully collusion-resistant public key broadcast encryption in which the ciphertext and the privatekey sizes are constant. In general, pairing-based broadcast encryption system is efficient in bandwidth and storing aspects than non-pairing based broadcast encryption system, however, it requires many computational costs that resource-constrained devices is not suit to be applied. In this paper, we propose a Broadcast Encryption scheme(called BEWD) that user can decrypt a ciphertext more efficiently. The scheme is based on Boneh et al.scheme. More precisely, it reduces receiver's computational costs by delegating pairing computation to a proxy server which computation is required to receiver in Boneh et al.scheme. Furthermore, the scheme enables a user to check if the proxy server compute correctly. We show that our scheme is secure against selective IND-RCCA adversaries under l-BDHE assumption.

Enhanced Antioxident Effect by over Expression of Tomato β-carotene Hydroxylase Gene (ChyB) Using Agrobacterium-infiltration in Tobacco Plant (Agro-infiltration을 이용한 토마토 β-carotene hydroxylase 유전자(ChyB) 과발현 및 담배식물체의 항산화 효과 증진)

  • Choi, Yoon-Jeong;Yoon, Kyung-Young;Yun, Hae-Keun;Suh, Sang-Gon;Moon, Yong-Sun
    • Horticultural Science & Technology
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    • v.29 no.3
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    • pp.267-272
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    • 2011
  • Several reports indicated that astaxanthin and zeaxanthin have more active anticancer activity than pro-vitamin A carotenes. ${\beta}$-carotene hydroxylase is a key enzyme to synthesize zeaxanthin and astaxanthin in carotenoids biosynthesis pathway. We isolated the ChyB gene encoding ${\beta}$-carotene hydroxylase from tomato leaves. The ChyB gene (1.5Kbp) fragment was cloned into the binary vector and designated to pIG121-ChyB-tom. Agrobacterium-mediated infiltration was used for transient assay in Nicotiana benthamiana. Leaf samples were collected 0, 1, 2, 3 days after infiltration (DAI). RT-PCR result showed that the expression of ${\beta}$-carotene hydroxylase transcripts was not detected in control (0DAI), but its expression was detected after 1 DPI and increased later on. When the activity of ${\beta}$-carotene hydroxylase was measured, the 1,1-diphenyl-pricryl hydrazyl (DPPH) radical scavenging activity (27%) at 2 DAI was significantly higher than that (21%) at 0 DAI. These results indicated that anti-oxidant activity dramatically increased at 2 DAI in tobacco leaves was due to over expression of tomato ${\beta}$-carotene hydroxylase. These results can be the foundation to develop tomato cultivars with high oxy-carotenoids content using the ChyB gene transformation.

Current Status of Registered Korean Patents Related to the Health Functional Food for Skin Care (피부미용 관련 건강기능식품 국내 특허 등록현황)

  • Chung, Kap-Taeck;Lee, Sang-Hyun
    • The Korean Journal of Food And Nutrition
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    • v.25 no.2
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    • pp.308-316
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    • 2012
  • Proper skin care promotes good metabolism and the biological activity of skin, helps maintain the skin in a healthy and beautiful state when combined with nutritional nourishment. Health functional foods are being used for the purpose of enhancing efficient skin care. Health functional foods related to skin care maintain the epidermis, dermal fibroblast layer and subcutaneous tissue that form the skin. Efficient functional foods alleviate the signs of endogenous aging that come with getting older and exogenous aging caused by sunlight. Even though the field of skin care related to health functional foods has received less attention and been the subject of less research compared to functional cosmetics which are developing widely, this area of skin care that maintains and improves the layer of dermal fibroblast through the intake of food, is expected to progress with the commercialization of products in many fields when the related technical research development is galvanized and the related patents are applied for. Research into health functional foods related to skin care in Korea started rather late in comparison to other advanced countries where patents for relevant techniques have been applied for since 1990's together with research conducted on how they might be used for practical purposes. This study used the key words 'skin care, health functional food' to search for Korean patents that have been applied for at the Korean Intellectual Property Office from 1983 to 2011 using the KIPRIS database, in order to help researchers in the related fields by organizing the patented formulas for health functional foods for skin care which have gained attention recently. According to the number of registrations in each industry field, the total number of patents was 1,120 we screened the major patents among them, the field with the largest number was food foodstuff non-alcoholic beverage and preparation or treatment(A23L) with 135, then natural plant medicine & medical supplies and cosmetics(A61K) with 112, microorganisms or enzymes(C12N) with 63, heterocyclic compounds(C07D) with 44, horticulture or cultivation of sea weeds, forestry(A01G) 16 times, listed from the highest to the lowest number of applications. It has been revealed that food, foodstuff, non-alcoholic beverage and preparation or treatment(A23L) was the industry field where the most patents for health functional foods related to skin care were registered.