• 한국환경농학회지
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• 제17권2호
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• pp.170-173
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• 1998

신천하수종말처리장에서 발생한 슬러지를 처리별로 시용한 다음 토양의 이화학성(理化學性)과 중금속 함량변화를 조사하였다. 슬러지 시용량이 증가함에 따라 질소, 인산 및 무기염류의 함량이 증가하는 것으로 나타 났으며, 토양의 입단화, 공극률 및 투수성이 증가하였으며 경도는 감소하였다. 중금속 함량은 Cr, Zn의 경우 약간의 증가를 보였으며,함류량이 적어 시용량이 증가하여도 함량에 차이가 없으며, 하층으로 이동하거나 용탈하지 않는 것으로 나타났다. Sludge중 중금속 함량이 매우 낮음으로 sludge의 처리가 토양 중금속 함량에 별다른 영향을 주지 않았다.따라서 토양의 하부(下部)로 이동하는 현상도 나타나지 않았다.

• 한국식품영양학회지
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• 제7권4호
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• pp.267-273
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• 1994

To provide the effective application scheme and basic information of buckwheat (Fagopyrum esculentum Moench), buckwheat was germinated at 10$^{\circ}C$ for 7 days and 100 kernels weight, germination rate, root length, chemical composition and mineral contents were examined at 24 hour Intervals. During the germination period, the 100 kernels weight increased approximately 0.3g per day. The germination rate increased sharply after 2 days and the root length increased greatly after 4 days. The crude protein contents increased with germination time, whereas the carbohydrate contents decreased. The crude ash and fat contents did not differ significantly during the germination period. The Ca contents Increased for the 4th day of gemination, but gradually decreased afterwords. The Na contents increased in the initial stage of germination, but then gradually decreased. However, there were no significant change In the Mg, K. Fe. Mn and Zn contents.

• 한국초지조사료학회지
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• 제11권1호
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• pp.22-29
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• 1991

This study was experimented to obtain the basic information on the changeable aspect and improvement of soil fertility in newly-reclaimed sloped land. Silage corn was cultivated under the six different treatments for 4 years. The relation between the amount or ratio of annual changes of soil physico-chemical properties and yield of silage corn were analyzed. Soil bulk density was decreased in 3rd year at topsoil, but that decreased in 4th year at subsoil. Soil organic matter also decreased in 2nd year at topsoil, and decreased continuously at subsoil. Bulk density and hardness of soil depths showed significant negative simple correlation with dry matter yield and cation exchange capacity showed positive. Correlation coefficient of chemical properties with dry matter yield were low. The range of annual changes of moisture percent, hardness and organic matter were wider than the other properties. The significantly different of physical properties were higher than the chemical properties, and those of topsoil were higher than subsoil. According to multiple regression between yield and physico-chemical properties of subsoil, bulk density and cation exchange capacity were in the greatest contribution at the variations, but bulk density was greatest at the ratios.

• Applied Biological Chemistry
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• 제35권4호
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• pp.286-293
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• 1992

개량식과 재래식 된장의 기호와 향기의 단점을 개선하고 장점을 유지하기 위하여 재래식, 개량식 그리고 납두를 혼합 제조한 된장의 이화학적 변화와 관능검사에 의한 적정배합 비율과 숙성정도를 검토하였다. pH는 개량식 메주에 납두의 배합량이 높을수록 증가하였으며 재래식 메주의 배합에서는 감소하였다. 재래식 메주에서의 질소화합물 함량은 개량식에서 보다 3배 높았으며 숙성도 빨랐다. 갈색색소의 변화는 초기의 값에 따르며 재래식이 높았다. 개량식과 재래식 그리고 납두를 혼합한 구가 관능적 평가가 높았으며 그 비율은 개량식, 재량식 그리고 남두의 비가 48 : 48 : 5의 비율이었다.

• 원예과학기술지
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• 제29권3호
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• pp.201-210
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• 2011

This experiment was conducted to investigate physical and chemical characteristics by volume fractions of root media using peatmoss, perlite, and vermiculite, along with effects on the growth of pot chrysanthemums (Dendranthema ${\times}$ grandiflorum 'Vemini') in a C-channel mat irrigation system. To evaluate the physico-chemical properties of 20 root media, the bulk density, particle density, total pore space, pore space, ash content, organic matter, pH, and electrical conductivity were measured and data were analyzed using principal component analysis (PCA). PCA scores revealed that physico-chemical properties changed by the blending of peatmoss, perlite, and vermiculite. The 20 root media were divided into three main groups by hierarchical cluster analysis. At the end of the experiment, the pH and EC of the root media were measured from media divided into four layers. The pH of root media without plants showed a strong linear relationship and the pH of root media with plants increased exponentially. The change of EC in the root medium was indicated as a hyperbolic curve. Plant growth characteristics according to growth in the 20 root media were analyzed by PCA. It was found that the mixing ratios of the root media affected plant growth characteristics. Therefore, mixing ratio is an important factor for pot-plant production in a subirrigation system.

• 농업과학연구
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• 제49권2호
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• pp.239-247
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• 2022

The physico-chemical properties of agricultural soil are factors that affect crop productivity and soil fertility. In Korea, agricultural environment change surveys have been conducted every four years since 1999. The purpose of this study is to investigate the status and changes in the physico-chemical properties of agricultural soil in Chungcheongnam-do. Samples were collected from the exact location of the aforementioned environment survey, and environmental variables (land use, type of crop cultivated) were investigated in relation to the samples. Soil collection was conducted using a core sampler and a single gouge auger. The bulk density of the soil generally increased up to a depth of sampling of 40 cm but decreased thereafter to a depth of 60 cm. Additionally, the bulk density was highest in the upland soil case and stood at 1.59 g·cm^-3, while the lowest value of 1.52 g·cm^-3 was obtained from orchard soil samples. Conversely, the porosity and moisture gradually decreased at soil depths of 0 - 40 cm and increased at depths of 40 - 60 cm. Most of the soil chemical properties generally decreased with an increase the soil depth from 0 to 70 cm, but electrical conductivity (EC) increased up to a depth of 40 cm. Therefore, it is judged that it is necessary to lower the bulk density by supplying organic matter for agricultural land in Chungcheongnam-do.

• 패션비즈니스
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• 제12권6호
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• pp.23-33
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• 2008

The physico-chemical characteristics by bleaching treatments were assessed by several instrumental analyses such as surface morphology, chemical structural change, color change as well as tensile strength. The change of morphological characteristic was observed through scanning electron microscope(SEM). The observation of the fine structure on hair surface by SEM showed the bleached hair had much damaged to hair cuticle, and some of cuticle surface were worn away. To investigate the chemical structural changes in hair keratin, the cross-sections of hair samples were directly analysed using Fourier transform infrared microspectroscopy(FT-IRM). The results showed the cysteic acid S=O band intensity was distinctively increased by performing the bleaching treatment. The cleavage of cystine was appeared to proceed primarily through the sulfur-sulfur (-S-S-) fission whereby cysteic acid was formed as a principal oxidation products. The distribution of amide I band in hair keratin was determined by attenuated total reflectance(ATR) FT-IR mapping image. The results showed that the outer side of hair cortex was more damaged than the inner side of the hair cortex. Also, during chemical bleaching of the hair with alkaline peroxide, the hair was turned to reddish yellow due to the oxidative degradation of eumelanin. This means the eumelanin is more unstable than pheomelanin in chemical oxidation. With bleaching, the tensile strength was also reduced as a results of the chemical oxidation.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.505-512
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• 1999

Soft marine clay deposits pose several foundation problems. Generally, lime stabilization is used worldwide for solidifying of soft marine clay deposits. In this paper, a series of laboratory tests were conducted to verify clay-lime reaction. A clay was collected from Pusan, which was mixed with various quantities of quick lime and slaked lime. Various compounds produced by clay-lime reaction were identified by X-ray diffraction analysis. The physico-chemical properties of the clay were also investigated. Compounds such as calcium silicate hydrate (CSH), calcium aluminate hydrate (CAH), calcium aluminate (CA), hillebrandite, and gehlenite were identified. It is likely that such compounds were mainly produced by pozzolanic reaction. Based on the change of physico-chemical properties obtained by the reaction, the water content was considerably decreased when lime was added to the clay. In addition, unconfined strength was increased. In the other hand, quick lime was more effective than slaked lime in decreasing and increasing of the water content and unconfined strength, respectively. Fewer cracks were produced when the clay was mixed with quick lime. It is suggested that these beneficial changes produced by the mixing of the clay and lime depend on the properties of compounds obtained by chemical reaction.

• 한국식품조리과학회지
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• 제14권2호
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• pp.177-181
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• 1998

감자 및 닭튀김의 튀김회수에 따른 튀김유의 물리화학적 특성의 변화를 경시적으로 측정하였다. 튀김유의 온도변화는 닭튀김의 경우보다 감자튀김의 경우 더 큰 것으로 나타났다. 튀김과정 중에 튀김재료인 냉동감자의 중량감소는 21.9% 정도이었으며 닭튀김의 경우 닭튀김물의 중량감소는 12.8% 정도인 것으로 나타내었다. 튀김횟수인 15회까지의 감자 튀김유와 닭튀김유의 산가는 튀김횟수에 따라 지속적으로 증가하였으며 이들의 산가는 모두 0.6이하로 나타났다. 튀김횟수인 15회까지의 감자와 닭튀김유의 과산화물가는 일률적으로 증가하지 않았다. 튀김횟수에 따른 감자와 닭튀김유의 요오드가의 변화는 거의 보이지 않았다. 감자 및 닭튀김시 튀김유의 색상은 튀김횟수가 증가함에 따라 R(red)및 Y(yellow)가 뚜렷이 증가되었으며, 닭튀김유는 감자튀김유보다 훨씬 높았다. 튀김횟수가 증가함에 따라 linoleic acid의 감소와 oleic acid의 상대적인 증가를 나타내었다. Linoleic acid의 감소와 oleic acid의 증가는 감자튀김유보다는 닭튀김유에서 더욱 큰 것으로 나타났다.

• 한국환경농학회지
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• 제31권1호
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• pp.75-95
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• 2012

BACKGROUND: Increase of heavy metals in agricultural ecosystem has become a social issue nationwide as it is related to public health. This review was performed to find out more systematic and integrated future researches on heavy metals using up to date articles published in the Korean journals related to agricultural environment. METHODS AND RESULTS: Researches on heavy metals in agricultural soils and plant uptake were categorized by the establishment of criteria, analytical methods, monitoring, management of source, characteristics and behavior in soil, plant uptake, bioavailability affecting physico -chemical properties in soil, risk assessment and soil remediation. In the early 1990s, the monitoring for heavy metals in soil has been widely performed. Accumulation of heavy metals in contaminated soil and availability to plants has also attracted interests to study the soil remediation using various physico-chemical methods. The phytoavailability and phytotoxicity of heavy metals have been mainly studied to assess the safety of agro-products using risk assessment techniques in the 2000s. CONCLUSION: Future direction of research on heavy metal in agricultural environment must be carried out by ensuring food safety and sustainability. A steady survey and proper management for polluted regions should be continued. Law and regulation must be modified systematically. Furthermore, studies should expand on mitigation of heavy metal uptake by crops and remediation of polluted fields.