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        검색결과 340

        1.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Bolivian tuber species like potato (Solanum tuberosum), native potato (Solanum sp), Oca (Oxalis tuberosa Molina), Olluco (Ullucus tuberosus Caldas), and Isaño (Tropaeolum turosum Ruíz & Pav.) hold extraordinary nutritional value and cultural significance, particularly within the Andean region. This study examined the mineral composition of Bolivian tuber species as an essential step toward understanding their nutritional significance and potential contributions to addressing dietary deficiencies. The research involved detailed analysis of diverse tuber cultivars, uncovering distinct mineral profiles across species. Native potato shows high levels of nitrogen (N), potassium (K), phosphorus (P), and magnesium (Mg) levels, alongside moderate micronutrients like iron (Fe) and zinc (Zn). Commercial potatoes exhibited prominence in N, P, and K, with moderate Fe, Zn, and manganese (Mn) levels. Oca, Isaño, and Papa Lisa displayed unique mineral concentrations, offering potential nutritional benefits. Intricate correlations and significant variances among elements highlighted the diverse mineral compositions among these tuber species. Multivariate analyses emphasized distinct mineral profiles unique to each species, revealing significant compositions of isaño and papa lisa's. The Multitrait Genotype- Ideotype Distance Index (MGIDI) identified isaño jaspeado, isaño and an unnamed native potato, AXT2, as promising ideotypes due to their exceptional mineral compositions. These findings provide comprehensive insights into Bolivian tuber species' various mineral compositions, underscoring their nutritional significance and potential in targeted breeding for improved dietary support and enhanced food security.
        4,200원
        2.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 생성형 인공지능인 챗봇을 활용해서 핵심광물을 탐구하는 과정에서 나타나는 챗봇과 학생의 반응, 그 들 사이에서 일어나는 상호작용을 인식론적 측면에서 분석했다. 그 결과를 바탕으로 인공지능을 활용한 교수·학습 과정 에서 유의해야 할 문제들을 교사의 역할, 교육의 목표, 지식의 속성 측면에서 논의했다. 이 연구를 위해 고등학생 19명 을 대상으로 챗봇을 활용한 3차시 과학 교육 프로그램을 진행했고, 학생들이 작성한 보고서를 분석했다. 그 결과, 학생 의 질문은 형식적 측면에서 검색형 질문과 탈검색형 질문이 나타났고 내용적 측면에서는 대상에 대한 특성을 묻는 다 양한 질문 외에도 여러 자료를 종합해서 판단할 것을 요구하는 질문도 나타났다. 대체로 학생들은 지향해야할 것과 지 양해야 할 것을 구분한 질문 전략을 갖추고 있었다. 챗봇의 답변은 일정한 형태-서문, 본문, 결문 등의 3부분으로 이루 어져 있었고, 특히 결문에는 내용에 대한 의견을 곁들인 논평이나 의견 등이 포함되어 있어서 여기에는 가치 판단과 함께 과학의 본성이 나타났다. 챗봇과 학생의 상호작용은 학생이 챗봇의 답변에 대한 질문을 조직하는 과정에서 잘 드 러났다. 답변 근거 여부에 따라 독립형, 파생형 질문으로, 포괄성 수준의 변화에 따라 상위형, 하위형, 병렬형 질문이 나타나기도 했다. 학생들은 챗봇의 답변에 비판적 사고기술이 포함된 질문으로 반응하기도 했다. 이러한 결과를 바탕으 로 챗봇과 학생 사이에는 교사와 상호작용하는 일반적 수업과 달리 ‘제한된 상호작용’이라는 태생적 한계가 있음을 발 견하고 이를 보완할 교사의 역할을 논의했고, 아울러 AI를 활용한 학습의 목표 및 이들이 제공하는 지식의 속성을 함 께 논의했다.
        5,200원
        3.
        2023.11 구독 인증기관·개인회원 무료
        The ultimate objective of deep geological repositories is to achieve complete segregation of hazardous radioactive waste from the biosphere. Thus, given the possibility of leaks in the distant future, it is crucial to evaluate the capability of clay minerals to fulfill their promising role as both engineered and natural barriers. Selenium-79, a long-lived fission product originating from uranium- 235, holds significant importance due to its high mobility resulting from the predominant anionic form of selenium. To investigate the retardation behaviors of Se(IV) in clay media by sorption, a series of batch sorption experiments were conducted. The batch samples consisted of Se(IV) ions dissolved in 0.1 M NaCl solutions, along with clay minerals including kaolinite, montmorillonite, and illite-smectite mixed layers. The pH of the samples was also varied, reflecting the shift in the predominant selenium species from selenious acid to selenite ion as the environment can shift from slightly acidic to alkaline conditions. This alteration in pH concurrently promotes the competition of hydroxide ions for Se(IV) sorption on the mineral surface as the pH increases and impedes the selective attachment of selenium. The acquired experimental data were fitted through Langmuir and Freundlich sorption isotherms. From the Freundlich fit data, the distribution coefficient values of Se(IV) for kaolinite, montmorillonite, and illite-smectite mixed layer were derived, which exhibited a clear decrease from 91, 110, 62 L/kg at a pH of 3.2 to 16, 6.3, 12 L/kg at a pH of 7.5, respectively. These values derived over the pH range provide quantitative guidance essential for the safety assessment of clay mineral barriers, contributing to a more informed site selection process for deep geological repositories.
        4.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We investigate the provenance of detrital garnets in Middle-Upper Jurassic sandstone of the Mino terrane, an accretionary complex in Southwest Japan, based on their chemical composition. The garnet grains in the Mino sandstone are mostly Fe-rich (almandine) and slightly Mg-rich (pyrope) species derived from high-grade metamorphic and intermediate to acidic plutonic rocks. The composition and interpreted origin of the garnets are generally consistent with those of metamorphic and igneous rocks of the Yeongnam Massif on the Korean Peninsula, a possible source region suggested in previous studies. In addition, two single grains of chromian spinel, an accessory mineral found in mafic to ultramafic rocks such as mantle peridotite, were found in one of the Mino sandstone samples. This finding suggests the possible presence of mafic to ultramafic rocks in the source area. The results of this study provide complimentary evidence for establishing a comprehensive tectonic and paleogeographical framework for the Mesozoic East Asian continent.
        4,200원
        5.
        2023.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        2023년 3월, EU는 안전하고 다양하며 저렴하고 지속 가능한 주요 원 자재 공급에 접근하는 포괄적인 조치인 핵심 원자재법(CRMA:Critical Raw Materials Act)을 채택하였다. CRMA의 핵심은 총 4가지로 구분 할 수 있다. EU전체 연간 소비량 대비 최소 10%이상을 역내에서 채굴 하고 핵심원자재 역내 가공량을 최대 40%이상으로 하며 핵심원자재 역 내 재활용 비율을 최소 15%까지 끌어올리기로 목표한 것이다. 또한 모 든 가공 단계에서 특정 국가에 대한 수입량을 EU연간 소비량의 65%를 제한 하였다. CRMA의 출현에 따라 중동부유럽 내에서 선전하고 있는 우리 자동차 기업과 배터리 생산기업에도 변화가 있을 것이며 핵심원자 재 법에 따른 대응방안을 강구해야 할 필요가 있다. 따라서 본 논문에서 는 중동부유럽 2차전지 기업 현황을 살펴보고 EU 핵심원자재법 출현에 따른 대응방안을 제시해 보고자 한다.
        6,100원
        6.
        2023.05 구독 인증기관·개인회원 무료
        Heavy water (D2O) is a coolant as well as a moderator of pressurized heavy water reactors (PHWRs). During operation of PHWRs, deuterium (H-2, D) in heavy water is gradually converted to tritium (H-3, T), which is a radioactive nuclide with a half-life of 12.3 years, by capturing neutron. Various radioactive wastes contaminated by T are generated upon the PHWR operation. Owing to the similarity of D and T, they behave together a form of water (either liquid or vapor) in a normal circumstance. To handle D and T with the water form is quite difficult because it is not a solid and is highly mobile in nature. In this study, a mineralization technique to fix D and T in a solid form is suggested. It is considered that hydroxide minerals, which have low solubility in water, might tightly bind D and T in non-mobile, solid-state media. Feasibility of this strategy is studied by using a copper-based hydroxide mineral, atacamite. Atacamite is a natural mineral found in copper deposits with chemical formula of Cu2Cl(OH)3. Atacamite can be simply synthesized in laboratories by a precipitation method using copper chloride and calcium carbonate as precursors. Both chemicals were added into heavy water to obtain pale-green precipitates. Heavy water is the only source for D in this reaction and thus deuterated mineral is expected to be form. The obtained deuterated mineral, suspected to be Cu2Cl(OD)3, was then immersed in natural deionized water (extremely low D2O concentration) for several days to identify how fast D in Cu2Cl(OD)3 dissolves into water. In a preliminary Fourier transform infrared (FTIR) spectroscopy, absorption peaks related to HDO and D2O were not observed in the deionized water which is recovered after the immersion test, suggesting that D remained stable in the synthesized mineral. However, owing to low detection limit of FTIR, more precise analysis should be taken to clearly identify the stability of D of the deuterated atacamite. If deuterated hydroxide minerals are found to have sufficiently high D stability in natural water, they can be further treated with cement or other stabilization media to form a final wasteform for underground disposal.
        7.
        2023.05 구독 인증기관·개인회원 무료
        For the deep geological repository, engineering barrier system (EBS) is installed to restrict a release of radionuclide, groundwater infiltration, and unintentional human intrusion. Bentonite, mainly used as buffer and backfill materials, is composed of smectite and accessory minerals (e.g. salts, silica). During the post-closure phase, accessory minerals of bentonite may be redistributed through dissolution and precipitation due to thermal-hydraulic gradient formed by decay heat of spent nuclear fuel and groundwater inflow. It should be considered important since this cause canister corrosion and bentonite cementation, which consequently affect a performance of EBS. Accordingly, in this study, we first reviewed the analyses for the phenomenon carried out as part of construction permit and/or operating license applications in Sweden and Finland, and then summarized the prerequisite necessary to apply to the domestic disposal facility in the future. In previous studies in Sweden (SKB) and Finland (POSIVA), the accessory mineral alteration for the post-closure period was evaluated using TOUGHREACT, a kind of thermal-hydro-geochemical code. As a result of both analyses, it was found that anhydrite and calcite were precipitated at the canister surface, but the amount of calcite precipitate was insignificant. In addition, it was observed that precipitate of silica was negligible in POSIVA and there was a change in bentonite porosity due to precipitation of salts in SKB. Under the deep disposal conditions, the alteration of accessory minerals may have a meaningful influence on performance of the canister and buffer. However, for the backfill and closure, this is expected to be insignificant in that the thermal-hydraulic gradient inducing the alteration is low. As a result, for the performance assessment of domestic disposal facility, it is confirmed that a study on the alteration of accessory minerals in buffer bentonite is first required. However, in the study, the following data should reflect the domestic-specific characteristics: (a) detailed geometry of canister and buffer, (b) thermal and physical properties of canister, bentonite and host-rock in the disposal site, (c) geochemical parameters of bentonite, (d) initial composition of minerals and porewater in bentonite, (e) groundwater composition, and (f) decay heat of spent nuclear fuel in canister. It is presumed that insights from case studies for the accessory mineral alteration could be directly applied to the design and performance assessment of EBS, provided that input data specific to the domestic disposal facility is prepared for the assessment required.
        8.
        2023.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was aimed to determine the effects of grow media on the mineral contents of the leaves and growth characteristics of strawberry grown under aquaponics system in a plant factory. For aquaculture, 12 fish (Cyprinus carpio) (total weight, 2.0 kg) were raised in an aquaponics tank (W 0.7 m × L 1.5 m × H 0.45 m, 472.5 L) filled with 367.5 L of water at a density of 5.44 kg·m-3 and total 34 of strawberry seedlings were transplanted in the pots filed with 200 g of orchid stone, hydroball or polyurethane sponge in the growing bed (W 0.7 m × L 1.5 m × H 0.22 m) laid out with holly acrylic sheet (140×60 mm, Ø80) on the top of the system. The pH and EC of the aquaponic solution was ranged from 7.6 to 4.9 and 0.24-0.91 dS·m-1, respectively. The concentration of NO3-N was about 28% lower than that of the hydroponic standard solution, and K, Fe and B were 10, 27 and 3.8 times lower, respectively; however, the mineral contents of strawberry leaves were in the appropriate ranges with lower contents in the leaves grown with sponge media. The organic content (OM), nitrogen (N), phosphorus (P), and potassium (K) of the sludge were 61.5, 5.72, 8.92, and 0.24%, respectively. The leaf area, leaf number, and dry and fresh weights of shoot at 81 DAT were significantly higher in the hydroball, and the average number of fruits per plant was significantly higher in both the orchid stone and hydroball. There was no significant difference in the fresh and dry weights of fruits. Integrated all the results suggest that the orchid stone and hydroball media are more effective to utilize nutrients in solid particles of aquaponic solution, compared to the polyurethane sponge.
        4,000원
        9.
        2022.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study compared the antioxidant and mineral properties of the leaves and seeds of fifteen Korean adzuki bean (Vigna angularis L.) breeding lines. This study was conducted in an attempt to expand the use of Korean adzuki bean leaves. The potassium, calcium, magnesium, and sodium contents of the leaves were significantly higher than the seeds, in particularly, the potassium content. The leaves had approximately 3.3 times higher potassium content than the seeds. For instance, the potassium content of YA1317 leaves was 21% higher than that of Arari. The total polyphenol content and ABTS activity of Adzuki bean leaves were significantly higher than the seeds, as opposed to the total flavonoid content and DPPH scavenging activity. Among the 15 breeding lines, YA1402 had 1.2~3.2 times higher antioxidant content and activity as compared to the Arari variety. It was concluded that adzuki bean leaves had higher mineral content, antioxidant component and activity as compared to the seeds. Therefore, adzuki bean leaves could be used an ingredient for dishes and as a medicine.
        4,000원
        10.
        2022.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        To confirm the applicability of crab apple, the composition and content of amino acids and minerals with ‘Fuji’ apple were measured. Apple and crab apple were extracted with water, 70% and 100% ethanol, respectively. The contents of polyphenols, flavonoids, and ascorbic acid, antioxidant activities of these extracts were measured. The amino acid composition of apples comprised a total of 17 amino acids. The total amino acid contents of apple and crab apple were 2,050.45 mg/kg and 900.05 mg/kg, respectively. For minerals, the total mineral content of apple and crab apple were 489.14 mg%, 529.77 mg%, respectively. The contents of polyphenols, flavonoids, and ascorbic acid of apple and crab apple extracts were highest in 70% ethanol extracts. The content of polyphenols, the crab apple extract, showed a generally higher content than the apple extract. The content of flavonoids, apple and crab apple extracts revealed no difference between extracts. The content of ascorbic acid, apple extract showed a generally higher content than the crab apple extract, but there was no significant difference between extracts. In the case of DPPH and ABTS radical scavenging abilities, 70% ethanol extract showed the highest antioxidant activity, and crab apple showed higher activity than apple extracts.
        4,000원
        11.
        2022.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The medicines for treating osteoporosis currently in use have minor to severe side effects, and can be financially burdensome. Thus, there is a need for prevention and alternative supplement that is relatively inexpensive, and can be easily consumed daily as an alternative dietary therapy. In this study, bone marrow density of the spine and femur of osteoporosis patients were checked before and after consuming complex composed of calcium and magnesium, considered to be the core of bone mineral content. November 2017-November 2021, patients with T-score of less than -2.5 or -1.0 < T-score < -2.5 with history of fractures or recent fractures were enrolled. The data of 60 patients who orally administered Ionized Cal/MagTM Complex were reviewed retrospectively, and it was significantly confirmed that the average value of T-score was up-regulated by 0.5. Additionally, the cumulative dose was observed to have a positive effect, on the improvement of BMD in the 2nd Lumbar and Femur neck. It is expected that better results will be achieved if use of the supplement is continued.
        4,000원
        12.
        2022.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The mineral content of Tricholoma matsutake was evaluated for comparison of mineral contents according to the area of cultivation. Ten domestic and thirty Chinese (10 Yanji, 10 Yunnan and 10 Tibet) T. matsutake specimens were assessed using an atomic absorption spectrophotometer (AAS) and inductively coupled plasma mass spectrometer (ICP-MS). The Na, Mg, K, and Ca contents of domestic T. matsutake were 128.12±85.25 mg/kg, 218.52±105.35 mg/kg, 7,534.58±2,691.52 mg/kg, and 17.69±7.14 mg/kg, respectively, while those of Yanji T. matsutake were 124.89±57.24 mg/kg, 64.07±27.52 mg/kg, 1,439.18±311.04 mg/kg, and 10.88±4.52 mg/kg, respectively. The Na, Mg, K, and Ca contents of Yunnan T. matsutake were 90.78±23.23 mg/kg, 77.40±28.36 mg/kg, 1,446.29 ±126.33 mg/kg, and 28.42±5.18 mg/kg respectively, while those of Tibet T. matsutake were 143.50±41.54 mg/kg, 124.64±50.18 mg/kg, 3,530.95±2,714.99 mg/kg, and 21.05±8.71 mg/kg, respectively. The Cu contents of domestic, Yanji, Yunnan, and Tibet T. matsutake were 105.43±32.97 mg/kg, 19.92±8.95 mg/kg, 54.51±16.91 mg/kg, and 64.80±23.01 mg/kg, respectively. Both domestic and Chinese T. matsutake samples showed significantly different K, Mg, and Cu levels in this study. Therefore, a comparative evaluation of the K, Mg, and Cu contents of multiple domestic and Chinese T. matsutake varieties is needed to determine the appropriate area of cultivation in the future.
        4,000원
        13.
        2021.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        In the majority of countries, the upper limit of buffer temperature in a repository is set to below 100℃ due to the possible illitization. This smectite-to-illite transformation is expected to be detrimental to the swelling functions of the buffer. However, if the upper limit is increased while preventing illitization, the disposal density and cost-effectiveness for the repository will dramatically increase. Thus, understanding the characteristics and creating a database related to the buffer under the elevated temperature conditions is crucial. In this study, a strategy to investigate the bentonite found in Korea under the elevated temperatures from a mineral transformation and radionuclides retardation perspective was proposed. Certain long-term hydrothermal reactions generated the bentonite samples that were utilized for the investigation of their mineral transformation and radionuclide retardation characteristics. The bentonite samples are expected to be studied using in-situ synchrotron-based X-Ray Diffraction (XRD) technique to determine the smectite-to-illite transformation. Simultaneously, the ‘high-temperature and high-pressure mineral alteration measurement system’ based on the Diamond Anvil Cell (DAC) will control and provide the elevated temperature and pressure conditions during the measurements. The kinetic models, including the Huang and Cuadros model, are expected to predict the time and manner in which the illitization will become detrimental to the performance and safety of the repository. The sorption reactions planned for the bentonite samples to evaluate the effects on retardation will provide the information required to expand the current knowledge of repository optimization.
        4,000원
        14.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 실험은 Holstein 비육후기에 홍삼박, 광물질 및 설탕을 첨 가 급여하여 건물채식량, 일당증체량, 육질특성 및 경제성에 미치는 영향을 조사하고자 수행하였다. 시험구는 4처리로서 홍삼박, 광물질 및 흑설탕을 급여하지 않는 처리구를 대조구(C), 홍삼박 200g 첨가 급여 구는 T1, 홍삼박 100g과 광물질 50g 첨가 급여구는 T2 그리고 광물질 50g과 흑설탕 20g 첨가 급여한 구를 T3 로 나누어 실시하였다. 그리고 본 실험에서 얻어진 결과를 요약해 보면 다음과 같다. 총 사료섭취량 및 1일 채식량은 T2 및 T3구가 C구에 비하여 유의적으로 높게 나타났다(p<0.05). 또한 채식량 이 많았던 T2 및 T3구에서 총 증체량 및 일당 증체량이 높게 나 타났지만 유의적인 차이는 없었다. 사료 요구율은 C구가 다른 구 (T1, T2, T3)에 비하여 유의적으로 높게 나타났지만(p<0.05), T1, T2 및 T3 구간에는 유의적인 차이가 없었다. 등지방두께, 등심단 면적 및 육량등급은 처리구 상호간 유의적인 차이가 없었다. 근내 지방은 T3(4.5) > T1(4.0) > T2(2.7) > C(2.5)구순으로 높게 나타났다(p<0.05). 그러나 육색, 지방색, 조직감 및 성숙도는 상호 처리 간 유의적인 차이가 없었다. 육질등급은 상호 처리 간 유의적인 차이는 보이지 않았지만 T3 > T1 > T2 > C 순으로 높은 경향을 보였다. 경제적 조수익성은 T3 > T1 > T2 > C구순으로 나타 났다. 이상의 결과를 종합해 볼 때, 배합사료와 조사료 만 급여하는 체계(C) 보다는 홍삼박, 광물질 및 흑설탕을 첨가 급여(T1,T2, T3)하는 체계가 도체등급 및 수익성 증대에 유리하며, 특히 증체량, 육질등급 및 경제성을 고려하였을 때 T3구가 가장 좋은 급여체계로 나타났다.
        4,000원
        15.
        2021.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : In this study, experimental findings regarding the frost resistance of concrete incorporated with mineral admixtures such as fly ash (FA) and ground granulated blast-furnace slag (SG) are presented. METHODS : To evaluate the performance of the abovementioned concretes under repeated freezing and thawing environments, based on the ASTM C 666 standard, the relative dynamic modulus of elasticity and mass ratio measurements are performed regularly. Furthermore, based on the ASTM C 672 standard, the concretes are exposed to 4% CaCl2 and NaCl salt solutions along with repeated 50 cycles of freezing and thawing. Subsequently, the scaling resistance is evaluated based on the scaled-off mass content and visual examination. RESULTS : SG is less effective in enhancing the scaling resistance of concrete compared with FA. However, the concrete incorporated with SG is more resistant to repeated freeze-thaw actions compared with OPC concrete. Meanwhile, compared with OPC concrete, the concrete incorporated with FA indicates a similar performance in terms of scaling resistance and better resistance against repeated freeze-thaw actions. CONCLUSIONS : The frost resistance of concrete depends significantly on the types of mineral admixtures used in concrete. This emphasizes the importance of selecting the appropriate binder to achieve durable concrete pavements in cold climate regions.
        4,000원
        18.
        2021.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 미네랄 첨가제가 한우사 바닥에 미치는 영향을 조사하였다. 실험은 경남 진주시 소재 한우 번식우 농장에서 실시하였다. 우방당 미네랄 첨가제를 5 ㎏ 첨가하였으며, 시험구로는 무첨가구(CON); bentonite 시험구(BN); illite 시험구(IL); 및 fly-ash 시험구(FA)로 두었다. 각각의 시험구로 4개의 우방을 이용하였으며, 우방당 5마리 한우 암소를 공시하였다. 미네랄 첨가제를 처리한 후 각 우방당 5곳에서 0, 7, 14, 21 및 28일에 우분을 채취하였다. 샘플은 건물, 발효특성, 미생물 성상 및 가스 발생량 분석에 이용되었다. 전 기간 동안 건물과 acetate 함량은 미네랄 첨가제에 의한 영향은 나타나지 않았다. 무첨가구에서 7, 14 및 28일에 유기물 함량은 가장 높았고(p<0.05), 조회분 함량은 가장 낮았다 (p<0.05). IL 시험구에서는 14, 21 및 28일에 총 질소 함량이 가장 높았고(p<0.05), IL, BN 및 FA 시험구에서는 각각 14, 21 및 28일에 무첨가구보다 대장균이 낮았다(p<0.05). FA 시험구에서는 28일에 살모넬라 수가 가장 높았다(p<0.05). IL 시험구에서는 28일에 암모니아 발생량이 가장 높았고 (p<0.05), 황화수소는 전기간 동안 검출되지 않았다. 28일간 결과값을 평균하였을 때, 무첨가구에서 유기물 함량이 가장 높았고(p<0.05), 조회분 함량이 가장 낮았다(p<0.05). IL 시험구에서 총 질소 함량이 가장 높았고(p<0.05), BN 시험구는 ㏗가 가장 높았다(p<0.05). 대장균 수는 IL 시험구에서 가장 낮았고(p<0.05), 살모넬라 수는 무첨가구 보다 IL과 FA 시험구에서 더 낮았다(p<0.05). 따라서, 본 연구에서 광물질 첨가제는 분 중 가스 발생량에는 영향을 미치지 않았으나, 병원성 미생물인 대장균은 illite와 fly-ash 처리 시에 억제되는 효과가 있었다.
        4,000원
        19.
        2021.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : In this study, an ASR-reducing (alkali-silica reaction) cement was developed to prevent the blow-up of concrete pavements. To develop ASR-reducing cement, various amounts of ground granulated blast furnace slag (GGBFS), and fly ash (FA) were substituted with Portland cement, and the ASR reduction effect was verified through various experiments. METHODS : The physical properties of ASR-reducing cement, varying with the substitution amounts of GGBFS and FA, were verified through compressive strength tests. In addition, the ASR reduction effect was examined using accelerated mortar bar tests. Furthermore, the reasons for the ASR reduction were investigated using microstructural analysis techniques, such as XRD and TG/DTG. RESULTS : There was a difference in the compressive strength results according to the amount of GGBFS and FA substitution. In addition, the samples with GGBFS and FA exhibited relatively lower compressive strengths at 3 days, than OPC samples, but the compressive strength at 28 days was higher than that of the OPC samples. The samples with GGBFS and FA had higher compressive strength at 28 days than OPC samples, because the substituted GGBFS and FA induced pozzolanic reaction. Through XRD and TG/DTG analyses, various degrees of pozzolanic reaction occurring in the samples were examined, and a more active pozzolanic reaction occurred in the samples with FA than in the samples with GGBFS. Therefore, it appeared that the ASR reduction effect occurred because of the induced pozzolanic reaction. CONCLUSIONS : GGBFS and FA substituting Portland cement indicated an ASR reduction effect, which was owing to the pozzolanic reaction. In addition, FA indicated a greater ASR reduction effect than GGBFS, which suggested that FA induced a more active pozzolanic reaction than GGBFS.
        4,000원
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