• 한국전기전자재료학회논문지
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• 제19권7호
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• pp.680-686
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• 2006

Tin oxide$(SnO_2)$ thin films were prepared on glass substrate by Plasma Enhanced Chemical Vapor Deposition (PECVD) method. $SnO_2$ thin films were prepared using gas mixture of dibutyltin diacetate as a precursor and oxygen as an oxidant at 275, 325, 375, $425^{\circ}C$, respectively as a function of deposition temperature. The XRD peaks corresponded to those of polycrystalline $SnO_2$, which is in the tetragonal system with a rutil-type structure. As the deposition temperature increased, the texture plane of $SnO_2$ changed from (200) plane to denser (211) and (110) planes. Lower deposition temperature and shorter deposition time led to decreasing surface roughness and electrical resistivity of the formed thin films at $325\sim425^{\circ}C$. The properties of $SnO_2$ films were critically affected by deposition temperature and time.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.356-357
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• 2006

Tin oxide thin films have been prepared on display glass from mixtures of dibutyl tin diacetate as a tin source, oxygen as an oxidant by Plasma Enhanced Chemical Vapor Deposition (PECVD) method. The relationships between the properties of tin oxide thin films and various reaction parameters such as the deposition temperature, deposition time and the oxygen gas flow rate were studied. As the deposition temperature increased, the texture plane of $SnO_2$ changed from (200) plane to denser (211) and (110) planes. Lower deposition temperature and thinner thickness of deposited film led to decreasing grain size, surface roughness and electrical resistivity of the formed thin films at $325{\sim}425^{\circ}C$. The properties of fabricated $SnO_2$ films are highly changed with variations of substrate temperature and deposition time.

• 원예과학기술지
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• 제17권3호
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• pp.337-340
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• 1999

장기 저장한 사과 화분의 활력을 측정하기 위하여 기본배지와 fluorescein diacetate(FDA)를 첨가한 배지를 slide glass 위에 얇게 도포한 후 기내발아율을 조사한 결과, FDA를 첨가한 배지에서는 화분 발아가 저하되었다. 따라서 FDA 용액을 이용한 형광염색반응법으로 사과 화분의 활력을 측정할 수 있는지 구명하기 위하여 10%의 sucrose 용액을 slide glass 위에 한방울 떨어뜨린 후 0.002%의 FDA를 첨가한 곳에 화분을 치상한 결과, 형광반응이 일어나는 치상 후 30분 경에 활력이 있는 화분은 자외선하에서 명확히 형광을 나타냈다. 기내발아율과 형광반응률을 측정한 결과, 39개월 장기 저장한 사과의 화분도 활력이 감소하지 않는 것으로 나타났다. 같은 방법으로 조사한 품종별 화분의 활력은 '후지' 와 '천추'가 가장 높게 나타났으며 '쓰가루'는 중간 정도, '조나골드'는 낮게 나타났다. 형광염색반응법에 의한 형광반응률은 대체로 기본배지에서의 발아율과 비슷하게 나타났으나 3개월간 저장한 '천추'의 화분은 형광반응률이 발아율보다 다소 높게 나타났다. 형광반응률과 발아율은 높은 정의 상관을 보여 형광염색 반응법에 의해 장기 저장 사과 화분의 활력을 편리하고 정확하게 측정할 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제19권7호
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• pp.718-726
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• 2009

The objective of this study was to develop and validate secondary models that can predict growth parameters of L. monocytogenes Scott A as a function of concentrations (0-3%) of a commercial potassium lactate (PL) and sodium diacetate (SDA) mixture, pH (5.5-7.0), and temperature (4-37DC). A total of 120 growth curves were fitted to the Baranyi primary model that directly estimates lag time (LT) and specific growth rate (SGR). The effects of the variables on L. monocytogenes Scott A growth kinetics were modeled by response surface analysis using quadratic and cubic polynomial models of the natural logarithm transformation of both LT and SGR. Model performance was evaluated with dependent data and independent data using the prediction bias ($B_f$) and accuracy factors ($A_f$) as well as the acceptable prediction zone method [percentage of relative errors (%RE)]. Comparison of predicted versus observed values of SGR indicated that the cubic model fits better than the quadratic model, particularly at 4 and $10^{\circ}C$. The $B_f$and $A_f$for independent SGR were 1.00 and 1.08 for the cubic model and 1.08 and 1.16 for the quadratic model, respectively. For cubic and quadratic models, the %REs for the independent SGR data were 92.6 and 85.7, respectively. Both quadratic and cubic polynomial models for SGR and LT provided acceptable predictions of L. monocytogenes Scott A growth in the matrix of conditions described in the present study. Model performance can be more accurately evaluated with $B_f$and $A_f$and % RE together.

• 한국해양학회지:바다
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• 제19권4호
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• pp.223-231
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• 2014

선박평형수를 통한 외래종 확산을 방지하기 위해 국제해사기구(IMO)에서는 2004년 선박평형수관리협약을 채택하였다. 이 협약에 따르면 앞으로 대부분의 선박들은 선박평형수 처리시스템을 통해서 해양 생물을 사멸 또는 제거시킨 후 배출해야 하며, 이는 플랑크톤의 생사판별방법을 통하여 이루어진다. 본 연구에서는 국제적으로 선박평형수 처리후 생사판별법으로 널리 사용되고 있는 fluorescein diacetate assay (FDA) 염색방법의 제한성과 이의 대안으로 Neutral red (NR) 염색방법사용 가능성을 살펴보고자 하였다. FDA 염색법은 대부분의 플랑크톤 염색에 되어서 현재 가장 널리 사용되는 방법임에도 불구하고 본 연구에서는 Ditylum brightwellii 을 제외한 모든 식물플랑크톤 대해서 낮은 염색 효율(전체 평균 염색 효율 <50%)을 보였으며, 식물플랑크톤이 갖는 고유한 형광(적색)에 간섭을 많이 받는 것으로 나타났다. 또한 FDA는 형광파장에 노출된 후 빠르게 색이 바래지는 경향도 관찰되었다. 반면에 NR은 조사된 모든 동 식물플랑크톤 개체수에 대해서 90% 이상의 높은 염색 효율을 보였다. 두 염색법 모두 포르말린을 이용해서 사멸시킨 동 식물플랑크톤에 대해서는 염색이 되지 않았다. 본 연구결과를 통해서 NR 염색법을 이용한 동 식물플랑크톤 생사판별은 매우 효율적이라고 판단된다.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2921-2927
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• 2011

This paper describes efficient synthetic approaches for isolating biologically interesting natural pyranochalcones and their unnatural derivatives from Mallotus Philippensis. The key strategies involve ethylenediamine diacetate-catalyzed benzopyran formation reactions and base-catalyzed aldol reactions.

• Bulletin of the Korean Chemical Society
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• 제28권10호
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• pp.1739-1745
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• 2007

A new methodology for the preparation of pyranochromenes was developed starting from substituted trihydroxybenzenes. This methodology was applied successfully to the total synthesis of biologically interesting compounds, clusiaphenone A, octandrenolone, O-methyloctandrenolone, trans-3''',4'''-dihydro- 3''',4'''-dihydroxy-O-methyloctandrenolone, trans-3'',4''-dihydro-3'',4''-dihydroxy-O-methyloctandrenolone, flemiculosin, laxichalcone, and racemic 3-deoxy-Ms-II.

• Bulletin of the Korean Chemical Society
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• 제26권12호
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• pp.1933-1936
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• 2005

Total synthesis of biologically interesting $({\pm})$-cannabichromene, $({\pm})$-cannabichromenic acid, and $({\pm})$-daurichromenic acid is described. The key step in the synthetic strategy involves the formation of benzopyrans by ethylenediamine diacetate-catalyzed reactions of resorcinols with $\alpha$,$\beta$-unsaturated aldehydes.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.566-570
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• 2011

An efficient and general synthesis of bibenzyl derivatives bearing pyranyl rings was achieved by ethylenediamine diacetate-catalyzed reactions of 3,5-dihydroxybibenzyl with ${\alpha},{\beta}$-unsaturated aldehydes in moderate yields. These reactions provided naturally occurring compounds 1 and 2 in single step reaction. As an application of this methodology, biologically interesting natural bauhinol D (8) was synthesized by a convergent sequence from readily available benzaldehyde and benzyl phosphonate.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2008년도 제39차 학술발표회
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• pp.19-20
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• 2008

Acetate fibers, such as diacetate and triacetate, were treated with ozone gas under atmospheric pressure and at a pressure of 40g/m3 and 100g/m3. The effect of the ozone-gas treatment was investigated on the basis of ESCA, FT-IR, x-ray diffraction, moisture regain, water absorption, and dyeing properties. The ozone-gas treatment caused an increase in the oxygen content of each fiber.