• 한국식품위생안전성학회지
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• 제34권6호
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• pp.551-556
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• 2019

세척수에 포함된 무기물질의 함량이 먹는 물의 수질기준을 초과하여, 참외 GAP 인증을 받지 못하는 사례가 최근 들어 종종 발생하고 있다. 이에 농업현장에서는 껍질을 제거하여 먹는 참외의 소비특성을 감안하여 세척수 수질기준의 일부를 완화해 줄 것을 요청하고 있다. 이에, 본 연구에서는 성주 지역에서 2017-2019년 GAP 인증 참외의 세척에 이용되는 지하수 142건의 수질자료를 근거로 무기물질 4종(불소, 비소, 철, 망간)의 인체 위해성을 평가하였다. 연구 결과, 성주 지역 GAP 참외의 세척에 사용되는 지하수를 음용수 수준으로 섭취하는 우리나라 국민의 4종 무기물질에 대한 HQ는 모두 평균 0.10 이하로 안전한 수준이었다. 특히, 심미적 영향물질인 철, 망간의 경우 성주 지역 지하수를 음용수 수준으로 섭취하는 경우 HQ가 평균 0.00. 과다노출군의 경우 0.01나타났는데, 일반 참외를 섭취하는 국민의 HQ(평균 0.01, 과다노출군 0.03)보다 낮은 수준이었다. 따라서, 성주 지역 지하수를 GAP 농산물의 세척에 활용하더라도 철, 망간을 포함한 4종 무기물질이 인체에 미치는 영향은 미미할 것으로 생각된다.

• Macromolecular Research
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• 제16권3호
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• pp.253-260
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• 2008

Environmentally friendly biocomposites were made using plant-based natural fibers, such as henequen and kenaf. The natural fiber reinforced polypropylene (PP) and unsaturated polyester (UP) biocomposites were examined in terms of the reinforcing effect of natural fibers on thermoplastic and thermosetting polymers. Kenaf (KE) and henequen (HQ) fibers were treated with an electron beam (EB) of 10 and 200 kGy doses, respectively, or with a 5 wt% NaOH solution. Four types of biocomposites (KE/PP, HQ/PP, KE/UP and HQ/UP) were fabricated by compression molding and each biocomposite was characterized by dynamic mechanical analysis and thermogravimetric analysis. The kenaf fiber had the larger reinforcing effect on the dynamic mechanical properties of both PP and UP biocomposites than the henequen fiber. The highest storage modulus was obtained from the biocomposite with the combination of UP matrix and 200 kGy EB treated kenaf fibers.

• 한국응용과학기술학회지
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• 제34권1호
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• pp.142-151
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• 2017

양이온 계면활성제는 살균력을 가지고 있으며 이를 개발하기 위한 연구는 다양한 산업분야에서 계속 진행되고 있다. 단순히 우수한 성능을 가질 뿐만 아니라 생분해성이 우수한 계면활성제를 개발하기 위한 연구는 증가되고 있다. 본 연구에서는 Michael addition 반응을 통하여 ester-type의 양이온 계면활성제를 합성하였다. 실온에서 촉매없이 alkyl acrylate와 1차 아민을 가지는 화합물을 합성한 뒤 dimethyl sulfate 로 4차화시킨다. 2개의 소수기와 한 개의 친수기를 갖는 HQ21과 2개의 소수기와 2개의 친수기를 갖는 HQ22를 합성하였다. 이들 합성화합물은 1H-NMR, HR-MS 와 FT-IR로 구조를 확인하였으며 생분해성을 측정하였다.

• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.204-210
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• 2014

The nitrogen doped porous carbon nanopolyhedrons (N-PCNPs)-multi-walled carbon nanotubes (MWCNTs) hybrid materials were prepared for the first time. Combining the excellent catalytic activities, good electrical conductivities and high surface areas of N-PCNPs and MWCNTs, the simultaneous determination of hydroquinone (HQ), catechol (CC) and resorcinol (RE) with good analytical performance was achieved at the N-PCNPs-MWCNTs modified electrode. The linear response ranges for HQ, CC and RE are 0.2-455 ${\mu}M$, 0.7-440 ${\mu}M$ and 3.0-365 ${\mu}M$, respectively, and the detection limits (S/N = 3) are $0.03{\mu}M$, $0.11{\mu}M$ and $0.38{\mu}M$, respectively. These results are much better than that obtained on some graphene or CNTs-based materials modified electrodes. Furthermore, the developed sensor was successfully applied to simultaneously detect HQ, CC and RE in the local river water samples.

• Macromolecular Research
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• 제12권2호
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• pp.195-205
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• 2004

We have synthesized new aromatic polyesters (DiPEG-HQ and DiPEG-BP) by condensation polymerization of a terephthalic acid derivative bearing a pendant oligo(oxyethylene) (DP = 7, MW = 350), which has a methoxy terminal group, and two different aromatic diols, hydroquinone and 4,4'-biphenoI. The synthesized polymers were characterized by differential scanning calorimetry (DSC), polarizing microscopy, and X-ray diffractometry for their liquid crystallinity (LC), thermal transitions, and structural morphologies in mesophases. The morphology of the LC phases depends strongly on the length of the rigid backbone repeating unit. The DiPEG-BP polymer having a longer repeating unit exhibits both layered and nematic structures before isotropization, whereas the DiPEG-HQ polymer having a shorter repeating unit shows only the layered structure in the mesophase. We found that the layer spacing for DiPEG-HQ is larger than that for DiPEG-BP. Both polymers easily form complexes with LiCF$_3$SO$_3$; we studied this complex formation by FT-IR spectroscopy. The layer spacing of the polymer-electrolyte composites increases upon increasing the amount of the lithium salt. The polymer/salt electrolyte mixtures we investigated at molar ratios of EO:salt in the range of 5-20 exhibit electrical conductivity values at 40$^{\circ}C$ of 2.4${\times}$10$\^$5/ and 1.1${\times}$10$\^$－5/ S/cm for DiPEG-HQ/LiCF$_3$SO$_3$ and DiPEG-BP/LiCF$_3$SO$_3$, respectively. At 80 $^{\circ}C$, these values are higher: 4.6${\times}$10$\^$－3/ and 1.1${\times}$10$\^$－4/ S/cm, respectively. The activation energy of conductivity depends strongly on the salt concentration.

• The Korean Journal of Physiology and Pharmacology
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• 제21권3호
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• pp.345-352
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• 2017

Since previous studies have reported that hydroquinone (HQ) exerted immunosuppressive and anti-inflammatory activity, various HQ derivatives have been synthesized and their biological activities investigated. In this study, we explored the anti-inflammatory activity of JS-III-49, a novel HQ derivative, in macrophage-mediated inflammatory responses. JS-III-49 suppressed the production of the inflammatory mediators nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) and down-regulated the mRNA expression of the inflammatory enzymes cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) as well as the expression of the pro-inflammatory cytokines interleukin-6 (IL-6) and IL-$1{\beta}$ without cytotoxicity in LPS-stimulated RAW264.7 cells. JS-III-49 inhibited nuclear translocation of the $NF-{\kappa}B$ transcription factors p65 and p50 by directly targeting Akt, an upstream kinase of the $NF-{\kappa}B$ pathway, in LPS-stimulated RAW264.7 cells. However, JS-III-49 did not directly inhibit the kinase activities of Src and Syk, which are upstream kinases of Akt, in LPS-stimulated RAW264.7 cells. Moreover, JS-III-49 suppressed the nuclear translocation of c-Fos, one of the components of AP-1, by specifically targeting p38, an upstream mitogen-activated protein kinase (MAPK) in the AP-1 pathway in LPS-stimulated RAW264.7 cells. These results suggest that JS-III-49 plays an anti-inflammatory role in LPS-stimulated macrophages by targeting Akt and p38 in the $NF-{\kappa}B$ and AP-1 pathways, respectively.

• 폴리머
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• 제37권5호
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• pp.618-624
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• 2013

Trimellitic anhydride chloride와 hydroquinone을 이용하여 hydroquinone bis(trimellitate anhydride)(HQ-TA)를 합성하였다. 합성된 HQ-TA와 6가지의 다양한 디아민들을 사용하여 전구체 polyamic acid(PAA)를 합성한 후, 열적-및 화학적-이미드화 반응을 거쳐 에스터 그룹을 가지는 폴리이미드(polyimide, PI) 필름을 합성하였다. PI 합성은 구조적으로 다양한 방향족 디아민을 사용하였다. 각 디아민 구조에 따른 유리전이온도($T_g$)는 167-$215^{\circ}C$를 보였고, 초기분해온도(${T_D}^i$)는 $364-451^{\circ}C$를 나타내었다. 가장 향상된 열팽창 계수(coefficient of thermal expansion, CTE)와 가스차단성은 TFB(3.23 $ppm/^{\circ}C$)와 4,4-ODA(< $10^{-2}cc/m^2/day$) 단량체를 각각 사용하였을 때 보였다. PI 필름의 투과도는 500 nm에서 65-89%를 보였으며, 노란색 정도를 나타내는 황색지수(yellow index, YI)는 3.01-69.52를 보였다.

• Imaging Science in Dentistry
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• 제33권1호
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• pp.27-33
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• 2003

Purpose : The purpose of this experiment was to evaluate the diagnostic ability of a CCD-based digital system (CDX-2000HQ) in the detection of incipient dental caries. Materials and Methods : 93 extracted human teeth with sound proximal surfaces and interproximal artificial cavities were radiographed using 4 imaging methods. Automatically processed No.2 Insight film (Eastman Kodak Co., U.S.A.) was used for conventional radiography, scanned images of conventional radiograms for indirect digital radiography were used. For the direct digital radiography, the CDX-2000HQ CCD system (Biomedisys Co. Korea) was used. The subtraction images were made from two direct digital images by Sunny program in the CDX-2000HQ system. Two radiologists and three endodontists examined the presence of lesions using a five-point confidence scale and compared the diagnostic ability by ROC (Receiver Operating Characteristic) analysis and one way ANOV A test. Results: The mean ROC areas of conventional radiography, indirect digital radiography, direct digital radiography, and digital subtraction radiography were 0.9093, 0.9102, 0.9184, and 0.9056, respectively. The diagnostic ability of direct digital radiography was better than the other imaging modalities, but there were no statistical differences among these imaging modalities (p > 0.05). Coclusion : These results indicate that new CCD-based digital systems (CDX-2000HQ) have the potential to serve as an alternative to conventional radiography in the detection of incipient dental caries.

• Imaging Science in Dentistry
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• 제33권2호
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• pp.91-95
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• 2003

Purpose : To compare the diagnostic accuracy of proximal caries detection between Kodak Insight film and the Biomedisys CDX2000HQ digital (CCD) sensor. Materials and Methods: 156 proximal surfaces of extracted teeth, 78 of which had chemical artificial caries, were used in this study. Four observers interpreted the radiographs using a five-point confidence rating scale to record their diagnoses. The results were analyzed by receiver operating characteristic curves, ANOVA and Kappa values. Result: Analysis using receiver operating characteristic curves revealed the areas under each curve which indicated a diagnostic accuracy of 0.951 in Insight and 0.952 in CDX2000HQ digital sensor. ANOVA revealed no significant differences between the two images with respect to caries detection. Kappa values indicated that the mean intra-observer agreement was 0.85 and inter-observer agreement 0.71 in conventional radiography. In digital radiography, the mean intra-observer agreement was 0.84 and inter-observer agreement 0.72. Conclusion: The results suggest that no significant difference exists between the two modalities for artificial caries detection and that CDX2000HQ was as good as Insight film for this purpose.

• 생명과학회지
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• 제20권8호
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• pp.1201-1206
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• 2010

현장의 환경 시료를 대상으로 Real-Time PCR법과 LC/MS법을 이용하여 마이크로시스틴 검출방법을 비교 연구하였다. 3종류의 primer쌍을 이용하여 3종의 Microcystis aeruginosa 표준균주를 대상으로 Real-Time PCR법을 실시한 결과 TOX2P/TOX2M primer를 이용한 균주에서만 마이크로시스틴이 검출되었다. 2009년 6~9월 사이에 남조류가 발생한 상수원수 시료를 정립된 Real-Time PCR법과 기존의 LC/MS법으로 실험한 결과 11개 시료 모두에서 마이크로시스틴이 검출되었고, 농도는 5.98~219.0 ${\mu}g/l$ 범위로 조사되었다. 정수처리 공정별 실험에서는 BAC 여과 단계에서 마이크로시스틴이 완전히 제거되는 것으로 나타났다. 실험결과 Real-Time PCR법은 기존의 표준시험방법인 LC/MS법 보다 분석시간을 많이 단축시키는 것으로 나타나 효과적인 마이크로시스틴 검출방법임을 알 수 있었다.