• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.1
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• pp.31-36
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• 2009

This study was conducted to find out an alternative way of rapid and accurate analysis of forage quality. Near reflectance infrared spectroscopy (NIRS) was used to evaluate the possibility of forage analysis and collect 258 samples such as barley for whole crop silage, forage corn and sudangrass from 2002 to 2007. The samples were analyzed for CP (crude protein), CF (crude fiber), ADF (acid detergent fiber), NDF (neutral detergent fiber) and IVTD (in vitro true digestibility), and also scanned using NIRSystem with wavelength from $400{\sim}2,400nm$. Multiple linear regression was used with wet analysis data for developing the calibration model and validate unknown samples. The important index In this experiment was SEC and SEP $r^2$ for CF, CP, NDF, ADF and IVTD in calibration set were 0.70, 0.86, 0.94, 0.94 and 0.89, also 0.47, 0.39, 0.89, 0.90 and 0.61 in validation sample, respectively. The results of this experiment indicates that NIRS was reliable analytical method to assess forage quality, specially in CF, ADF and IVTD, sample should be included for respective forage samples to get accurate result. More robust calibrations can be made to cover every forage samples if added representative sample set.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.1
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• pp.29-34
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• 2021

Near infrared reflectance spectroscopy (NIRS) is routinely used for the determination of nutrient components of forages. However, little is known about the impact of sample preparation and wavelength on the accuracy of the calibration to predict minerals. This study was conducted to assess the effect of sample preparation and wavelength of near infrared spectrum for the improvement of calibration and prediction accuracy of Calcium (Ca) and Phosphorus (P) in imported hay using NIRS. The samples were scanned in reflectance in a monochromator instrument (680-2,500 nm). Calibration models (n = 126) were developed using partial least squares regression (PLS) based on cross-validation. The optimum calibrations were selected based on the highest coefficients of determination in cross validation (R2) and the lowest standard error of cross-validation (SECV). The highest R2 and the lowest SECV were obtained using oven-dry grinded sample preparation and 1,100-2,500 nm wavelength. The calibration (R2) and SECV were 0.99 (SECV: 468.6) for Ca and 0.91 (SECV: 224.7) for P in mg/kg DM on a dry weight, respectively. Results of this experiment showed the possibility of NIRS method to predict mineral (Ca and P) concentration of imported hay in Korea for routine analysis method to evaluate the feed value.

• Economic and Environmental Geology
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• v.15 no.4
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• pp.205-219
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• 1982

The Eosangcheon manganese ore deposits occur as supergene weathering deposits along quartz porphyry dikes developed in the Ordovician Heungweolri dolomite and Samtaesan limestone formations. The manganese ores are composed of manganese oxide minerals and associated other minerals. Rancieite and todorokite are abundantly found, and birnessite, nsutite, pyrolusite and chalcophanite are found in minor quantities. Associated other minerals are calcite, gypsum, goethite, lepidocrosite, quartz, and sericite. Microscopic, chemical, X-ray powder diffraction, infrared absorption spectroscopic and differential thermal analyses have been made for manganese oxide minerals and associated other minerals. The relationship of birnessite and rancieite was studied by means of X-ray powder diffraction and infrared absorption spectroscopic analyses. It is assumed that these minerals are closely related to each other in crystal structure, but separate species. The manganese oxide minerals were formed mainly by replacement, precipitation from solution, and recrystallization in the supergene weathering environment. The trend of formation of manganese oxide minerals is: (Rhodochrosite)-(todorokite)-(birnessite, rancieite)-(nsutite, pyrolusite, chalcophanite).

• Elastomers and Composites
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• v.47 no.3
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• pp.210-215
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• 2012

Whitening phenomena of the EPDM composites with different inorganic filler compositions which were aged at $90^{\circ}C$ for 7 days in air and tap water atmospheres, respectively, were investigated. The aged samples in tap water containing stearic acid exhibited severe whitening phenomena, while all the samples aged in air did not show any whitening. Depending on the filler compositions, there was no big difference in the whitening phenomena. The whitening materials were analyzed using gas chromatography/mass spectrometry (GC/MS), image analysis, energy-dispersive X-ray spectroscopy (EDX), and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The whitening materials were identified to be salts of stearic acid. The salts of stearic acid were formed by reaction of metal cation in tap water and stearic acid in the sample.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.04a
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• pp.340-344
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• 2011

건축물 마감재료의 연소시 발생되는 독성가스는 대형화재로 인한 인명피해의 주된 원인 중의 하나이다. 현행 건축법에서는 건축물마감재료에 대하여 동물의 평균행동정지시간을 측정하는 가스유해성시험을 실시하고 있다. 본 연구는 동물시험이 아닌 NFPA 269에 의한 유효량분율(FED: Fractional effective does)을 이용하여 건축물 마감재의 독성지수를 도출하였다. 현행 가스유해성 평가 방법에서 사용되는 채임버(피검상자)를 이용하여 적외선분광분석 및 산소분석기로 연소가스를 정량 분석하였으며, NFPA269에서 규정하는 FED를 도출하였다. 몇 가지 건축재료에 대한 가스유해성시험의 평균행동정지시간과 FED의 상대적인 비교를 통해 연소가스독성평가를 수행하였다.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.526-531
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• 2010

For efficient use of wood, it is important to control moisture of wood in processing wood. Near-infrared (NIR) spectroscopy can be used to estimate the physical and chemical properties of materials quickly and nondestructively. In this study, it was intended to measure the moisture contents on the surface of wood using NIR spectroscopy coupled with multivariate analytic statistical techniques. Because NIR spectroscopy is affected by the chemical components of the specimens and contains signal noise, a regression model for detecting moisture content of wood was established after carrying out several numerical pretreatments such as Smoothing, Derivative and Normalization in this study. It shows that the regression model using NIR absorbance in the range of 750~2,500 nm predicts the actual surface moisture content very well. Near-infrared spectroscopy technique developed in this study is expected to improve a technology to control moisture content of wood in using and drying process.

• Applied Chemistry for Engineering
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• v.5 no.2
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• pp.361-372
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• 1994

Vanadium containing MFI type zeolites have been prepared hydrothermally or by the impregnation method with $NH_4VO_3$ solution after dealumination of HZSM-5. Incorporation of vanadium into the framework of zeolite has been demonstrated by XRD, DTA, FT-IR and ESR analyses. Upon $NH_4VO_3$ impregnation and calcination of dealuminated zeolite, vanadium substitution into the framework could be performed like a hydrothermally synthesized zeolite. Vanadium in zeolite is able to pass redox cycles at high temperatures, and it is shown that vanadium is probably fixed and atomically dispersed in the structure of zeolite. The catalytic benzene hydroxylation, hexanes and alcohols oxidation were used for evaluating the properties of vanadium incorporated MFI zeolite.

• 사료
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• s.63
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• pp.70-76
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• 2013

사료에 있어서 가장 중요한 영양소 중에 하나는 단백질이다. 단백질은 가축의 성장, 유지, 생산근육, 효소, 호르몬, 우유, 털 등)에 필수적인 영양소이다. 가축의 단백질 요구량은 가축의 성장단계, 개체크기, 유전적인 능력 등에 따라 달라진다. 그러므로 가축에게 공급되는 단백질의 양은 정확하게 평가되어야한다. 너무 과도한 단백질 공급은 동물이 불필요한 에너지를 생산하게 만들고 너무 적은 단백질 공급은 아미노산 결핍이 일어나게 할 수 있다. 가축이 요구하는 정확한 양의 단백질을 공급하는 것이 중요하고 이를 위해서는 사료내 단백질의 양을 정확하게 분석하는 것이 선행되어야 한다. 사료에 있어 단백질 함량은 사료 내 질소의 양을 정량해서 간접적으로 환산하고 추정한 조단백질(Crude Protein)로 표현한다. 샘플내의 질소가 모두 아미노산에서 온 것이라고 가정하고, 단백질이 평균적으로 16%의 질소를 가지고 있기 때문에 (1/0.16=6.25) 정량한 질소수치에 단백질 환산 계수 6.25를 곱해서 표현한다. 그러나 사료원료마다 아미노산 조성이 다르기 때문에 사료원료마다 다른 단백질 환산 계수를 사용해야 한다는 주장도 있다. 단백질 환산 계수에 관한 리뷰논문을 보면 대두의 경우 5.71에5서부터 유제품의 경우 6.38에 이르기까지 다양하다. 그러나 논란의 여지가 있기 때문에 이렇게 매트릭스마다 다른 단백질 환산 계수를 사용할 경우 계산식 옆에 사용한 환산계수를 적어 주어야 한다. 사료 내 조단백질을 정량하는 방법은 켈달법(Kjeldahl method), 듀마스법(combustion method), 근적외선분광분석법(NIR, Near Infrared) 등이 있는데 여기서는 주로 사료분석기관과 사료업계에서 조단백질 분석에 많이 사용하고 있는 켈달법과 듀마스법을 비교해 보고자 한다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.1
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• pp.13-19
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• 1996

This study was conducted to establish the rapid determination method for major components of maturing covered barley grains, and to improve the efficiency of selection in barley breeding. Near Infrared Reflectance Spectroscopy (NIRS) is an established, economical and nondestructive technique applied widely to the food and feed industry. 34 barley lines were sampled at 5 day-interval from 25 to 35 days after heading. A standard regression analysis for the data obtained by analytical laboratory methods and NIRS method was carried out to get a useful calibration equation. The simple significant correlation between these two methods at 25 days after heading was recognized in starch and $\beta$-glucan contents. At 30 days after heading the data obtained by two methods showed significant correlation in starch, $\beta$-glucan and protein contents. Analyzed data and that from NIRS method at 35 days after heading was significantly correlated in starch and protein contents. It was concluded that the applicability of NIRS method for the components analysis in maturing barley grains was different depending on maturing stages and components.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.2
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• pp.125-130
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• 2015

The objective of this study was to investigate the feasibility of using near infrared spectroscopy (NIRS) to discriminate between grass spices. A combination of NIRS and chemometrics was used to discriminate between Italian ryegrass, perennial ryegrass, and tall fescue seeds. A total of 240 samples were used to develop the best discriminant equation, whereby three spectra range (visible, NIR, and full range) were applied within a 680 nm to 2500 nm wavelength. The calibration equation for the discriminant analysis was developed using partial least square (PLS) regression and discrimination equation (DE) analysis. A PLS discriminant analysis model for the three spectra range that was developed with the mathematic pretreatment "1,8,8,1" successfully discriminated between Italian ryegrass, perennial ryegrass, and tall fescue. An external validation indicated that all of the samples were discriminated correctly. The discriminant accuracy was shown as 68%, 78%, and 73% for Italian ryegrass, perennial ryegrass, and tall fescue, respectively, with the NIR full-range spectra. The results demonstrate the usefulness of the NIRS-chemometrics combination as a rapid method for the discrimination of grass species by seed.