• 펄프종이기술
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• 제41권1호
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• pp.1-8
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• 2009

Mountain Pine Beetle (MPB) attacked pine was evaluated for pulp quality, chemical and physical properties, and bleachability. Chemical analyses showed that the dehydroabietic acid and total acetone extractives content were higher in the year 3 (grey) attacked MPB chips and lower in the year 5 (grey) attacked MPB chips as compared to a typical SPF (spruce/pine/fir) reference. Lignin and carbohydrate content of the MPB wood chips were comparable to the SPF. Similarly, there was little difference in kappa number, pulp yield and liquor consumption between the 3 and 5 year MPB attacked wood. Likewise there was no significant difference in the resulting tear strength, burst, or tensile strength. There appeared to be an improved bleaching response in the MPB attacked pulp as compared to the SPF reference, but this was accompanied by a slightly lower bleached pulp yield and higher bleach filtrate COD and solids content.

• Near Infrared Analysis
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• 제1권2호
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• pp.41-44
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• 2000

The objectives of this study are to discriminate the geographical origin and cultivation years of ginseng based on the near-infrared(NIR) reflectance spectroscopic analysis. Korea and China ginseng samples were prepared for discrimination of geographical origin. 4, 5 and 6 years-old ginseng samples from Korea were prepared for discrimination of cultivation years. Used spectrometer were InfraAlyzer 500, InfraAlyzer 400 and Fiber optic. Sample type of ginseng was 3, whole ginseng radix, slide section and powder type. The accuracy was affected by sample types and instruments. The accuracy for discrimination geographical origin was 97% in calibration model using IA 500 and ginseng powder. For discrimination of cultivation years, the model with slide selection using IA500 were relative accurate. The accuracy was 96.7% for 4-year, 91.3% for 5-year and 89.3% for 6-year old ginseng. The study shows that NIR spectroscopic analysis can be used to discriminate the geographical origin and cultivation years of ginseng with acceptable accuracy.

• Near Infrared Analysis
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• 제2권1호
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• pp.55-58
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• 2001

The object of this work was to investigate the influence of growing district and harvest year on calibration for sweetness (Brix) determination of Fuji apple fruit using near infrared (NIR) reflectance spectroscopy, and to develop the robust calibration across these variation. The calibration models was based on wavelength range of 1100∼2500 nm using a stepwise multiple linear regression. A calibration model by sample set of one growing district was not transferable to other growing districts. The combined calibration (data of three growing districts) predicted reasonable well against a population set drawn from all growing districts (SEP=0.69, Bias=0.075). A calibration model by sample set of one harvest year was not also transferable to other harvest years. The combined calibration (data of three harvest years) predicted well against a population set drawn from all harvest years (SEP=0.53, Bias=0.004).

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1614-1614
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• 2001

The sweetness (。Bix) of fruit is the main quality factor contributing to the fruit taste. The brix of the apple fruit can be measured non-destructively by near infrared (NIR) spectroscopy, allowing the sweetness grading of individual apple fruit. However, the fruit quality is influenced by various factors such as growing location, producing year, variety and harvest time etc., accordingly the robust NIR calibration is required. In this experimental results are presented the influence of two variations such as growing location and producing year of apple fruit in establishing of calibrations for sweetness, and developed a stable and highly accurate calibration. Apple fruit (Fuji) was collected every year from 1995 to 1997 in 3 different growing locations (Andong, Youngchun and Chungsong) of Kyungpook in Korea. NIR reflectance spectra of apple fruit were scanned in wavelength range of 1100∼2500nm using an InfraAlyzer 500C (Bran+Luebbe) with halogen lamp and PbS detector. The multiple linear regression and stepwise was carried out between the NIR raw spectra and the brix measured by refractometer to select the best regression equations. The calibration models by each growing district were well predicted to dependent sample set, but poorly predicted to independent sample set. Combined calibration model using data of three growing districts predicted reasonable well to a population set drawn from all growing districts(SEP = 0.69%, Bias=-0.075). The calibration models by each harvest year were not transferable across harvest year, however a combined calibration model using data of three harvest years was sufficiently robust to predict each sample sets(SEP = 0.53%, Bias = 0.004).

• Applied Biological Chemistry
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• 제39권6호
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• pp.517-520
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• 1996

재배도라지 3년근과 24년근을 SDE방법으로 추출하여 본 결과 휘발성분은 3년근에서 54.71 mg%, 24년근에서 80.01 mg%가 각각 포집되었다. 이들을 각각 GC/MS(TIC)로 분석한 결과 3년근에서는 24종 24년근에서는 28종의 휘발성분이 확인되었다. 특히 hexanol, trans-2-hexenol, nonanal의 휘발성분은 3년근에 비해 24년근에서 10배 이상 검출되었다. 도라지 24년근의 휘발성분을 GC/MS로 동정한 결과 주요성분으로 hydrocarbon류 10종, alcohol류 8종, aldehyde류 10종, ester류 5종, acid류 6종, 기타 1종의 휘발성분이 검출되었다. 도라지 휘발성분의 종류와 함량은 3년근보다 24년근에서 높게 나타나는 것으로 사료된다.

• 한국표면공학회지
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• 제54권6호
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• pp.294-301
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• 2021

As the number of cases of performance degradation owing to corrosion of plant during processing in industries increases, the cost of maintaining industrial factory is increasing year by the year. Most of the materials of the facilities are consist of stainless steel (SS) such as austenite SS, ferrite SS, martensite SS, and duplex SS. Among them austenite SS is cheap and has excellent corrosion resistance and heat resistance. Corrosion is the consumption and change of metals by altering chemical and electrical reactions. The types of SS corrosion include pitting corrosion, crevice corrosion, galvanic corrosion, stress corrosion cracking, and thermal corrosion. The corrosion of SS is not only investigated various environmental factors but also the measurement of the corrosion rate. Therefore, it aims to understand comprehensive corrosion rates in various environments using qualitative, quantitative and electrochemical methods.

• Journal of Ginseng Research
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• 제48권2호
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• pp.229-235
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• 2024

Background: Plant health is directly related to the change in native microbial diversity and changes in soil health have been implicated as one of the main cause of root rot. However, scarce information is present regarding allelopathic relationship of Panax notoginseng root exudates and pathogenic fungi Fusarium oxysporum in a continuous cropping system. Methods: We analyzed P. notoginseng root exudate in the planting soil for three successive years to determine phenolic acid concentration using GC-MS and HPLC followed by effect on the microbial community assembly. Antioxidant enzymes were checked in the roots to confirm possible resistance in P. notoginseng. Results: Total 29 allelochemicals in the planting soil extract was found with highest concentration (10.54 %) of p-hydroxybenzoic acid. The HPLC showing a year-by-year decrease in p-hydroxybenzoic acid content in soil of different planting years, and an increase in population of F. oxysporum. Moreover, community analysis displayed negative correlation with 2.22 mmol. L^-1 of p-hydroxybenzoic acid correspond to an 18.1 % population of F. oxysporum. Furthermore, in vitro plate assay indicates that medium dose of p-hydroxybenzoic acid (2.5-5 mmol. L^-1) can stimulate the growth of F. oxysporum colonies and the production of macroconidia, as well as cell wall-degrading enzymes. We found that 2-3 mmol. L^-1 of p-hydroxybenzoic acid significantly increased the population of F. oxysporum. Conclusion: In conclusion, our study suggested that p-hydroxybenzoic acid have negative effect on the root system and modified the rhizosphere microbiome so that the host plant became more susceptible to root rot disease.

• 한국균학회지
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• 제30권2호
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• pp.95-98
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• 2002

송이 균환의 생장을 알아보기 위하여 1) 균환 선단의 1년간($1999{\sim}2000$) 생장 길이 측정과 2) 2000년의 균환선단을 기점으로 $1997{\sim}2000$년 송이 발생위치간의 거리를 측정하였다. 65년생 소나무림에서 송이 균환 선단은 1년간 평균 11.3cm 생장하였고 ($1999{\sim}2000$), 연도별 ($1997{\sim}2000$) 송이 자실체 발생위치는 연평균 11.3cm 이동하였다. 또한 송이 균환 선단에서 송이 버섯간 거리는 2000년 경우에는 균환선단 안쪽 13.8cm에서 발생하였다. 따라서 당년의 송이 발생위치는 1년 전에 땅속의 송이균사들이 생장하였던 곳임을 알 수 있었다. 송이는 송이 균환의 보호 차원에서 송이 버섯발생 위치에서 50cm 떨어진 밖에서 채취하는 것이 바람직할 것으로 생각되었다.

• 농약과학회지
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• 제16권2호
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• pp.131-136
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• 2012

수삼 중 azoxystrobin과 difenocoanzole의 잔류특성을 구명하기 위하여 2009년 3년근 수삼에 시험농약을 안전사용기준에 따라 2년간 살포한 후 잔류량을 분석하였으며, 시험농약의 정량한계는 0.003 mg/kg이었다. 회수율이 87.58-112.79%임을 감안할 때 수삼 중 잔류농약 분석법은 적합하였다. 3년근 및 4년근 수삼 중 azoxystrobin의 잔류량은 각각 0.004-0.011 mg/kg과 0.007-0.016 mg/kg이었으며, difenoconazole은 3년근과 4년근 수삼에 0.003-0.007 mg/kg과 0.007-0.01 mg/kg 잔류하여 누적잔류특성은 나타나지 않았다.

• 대한화학회지
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• 제60권6호
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• pp.428-435
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• 2016

Effective mastering and learning of basic organic chemical concepts is pivotal to ensure students continue to excel to the higher levels of organic chemistry learning. Concept learning is crucial for first-year organic chemistry students so that they can comprehend and understand a concept better and able to make connection to problems. In the present paper, the authors have implemented the Interactive Anonymous Quiz (IAQ) with "must-have" features in the organic chemistry course as a teaching tool to instill students' interest and enhance conceptual understanding in organic chemistry. The effectiveness of this activity was examined and evaluated through students' reflective writing. Students showed positive learning outcome on the implemented activity as reflected by the reflective writings. In addition, this activity could be employed as an activity to check on students' concept understanding, to instill students' interest in organic chemistry course and to improve on students' weakest topic in organic chemistry in the future classes.