• Journal of Welding and Joining
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• 제31권2호
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• pp.21-25
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• 2013

Aluminum alloys have been considered for substantial use in these industries. This ensues from their attractive strength to weight ratio, superb formability, apposite weldability and acceptable corrosion resistance. Depending on the specific application, corrosion behavior is a significant factor of a welded joint. In this study, recent researches in the view of corrosion resistance of friction stir welded aluminum alloys are briefly reviewed.

• 아시안잔디학회지
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• 제18권4호
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• pp.211-219
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• 2004

Transgenic zoysiagrass (Zoysia japonica cv. Zenith) plants have been obtained by particle bombardment of embryogenic callus with the plasmid pSMABuba, which contains hygromycin resistance (hpt) and bialaphos resistance (bar) genes. Parameters on DNA delivery efficiency of the particle bombardment were partially optimized using transient expression assay of a chimeric $\beta-glucuronidase$(gusA) gene driven by the CaMV 35S promoter. Stably transfarmed zoysiagrass plants were recovered with a selection scheme using hygromycin. Transgenic zoysiagrass plants were confirmed by PCR analysis with specific primer for bar gene. Expression of the transgene in transformed zoysiagrass plants was demonstrated by Reverse transcriptase (RT)-PCR analysis. All the tested transgenic plants showed herbicide BastaR resistance at the field application rate of $0.1\%-0.3\%$.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.378.1-378.1
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• 2014

In this study, we investigated that the resistance switching characteristics of Nb-doped HfO2 films with increasing Nb doping concentration. The Nb-doped HfO2 based ReRAM devices with a TiN/Nb-doped HfO2/Pt/Ti/SiO2 were fabricated on Si substrates. The Nb-doped HfO2 films were deposited by reactive dc magnetron co-sputtering at $300^{\circ}C$ and oxygen partial ratio of 60% (Ar: 16sccm, O2: 24sccm). Microstructure of Nb-doped HfO2 films and atomic concentration were investigated by XRD, TEM, and XPS, respectively. The Nb-doped HfO2 films showed set/reset resistance switching behavior at various Nb doping concentrations. The process voltage of forming/set is decreased and whereas the initial current level is increased in doped HfO2 films. However, the switching properties of Nb-doped HfO2 were changed above the specific doping concentration of Nb. The change of resistance switching behavior depending on doping concentration was discussed in terms of concentration of non-lattice oxygen and micro-structure of Nb-doped HfO2.

• 한국연소학회지
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• 제15권1호
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• pp.30-37
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• 2010

Carbonization characteristics of Indonesian bamboos were investigated using lab-scale tube furnace, in order to find optimum design temperature of a carbonizer for producing bamboo charcoal and vinegar. The bamboo samples used in this study are local bamboos from Damyang in Korea, Andong and Petung in Indonesia. Correlation of electric resistance, specific surface area and pH of bamboo vinegar with pyrolysis temperature has been investigated. Electric resistance of the charcoal increased for higher pyrolysis temperature the specific surface area was also increased as carbonization temperature got higher. Charcoal which has specific surface area of over $300\;m^2/g$ could be produced at $700^{\circ}C$. pH of bamboo vinegar was decreased for highter carbonization temperature and vinegar under pH 3 could be produced for all bamboo samples. In this experimental condition, it was found that lower carbonization temperature is better for producing bamboo vinegar of high quality, while higher temperature is better for obtaining bamboo charcoal with larger surface.

• 한국식품조리과학회지
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• 제31권1호
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• pp.18-25
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• 2015

This study investigated the baking properties of sorghum with the addition of xylanase or Pentopan, which is a baking additive containing xylanase. The control bread was made with a 30% substitution for wheat flour and the optimum level of enzyme addition was 0.75 mg/g flour for Pentopan and 5 mg/g flour for xylanase. The water binding capacity of wheat flour increased with the addition of sorghum, but decreased with the addition of either xylanase or Pentopan. The resistance of dough increased while extensibility decreased with the addition of sorghum; however, resistance decreased while extensibility increased with the addition of the enzyme. Specific volume of bread decreased significantly with the addition of sorghum. However, the specific volume was significantly recovered with the addition of enzyme. Crumb firmness was higher in the sorghum-added sample, but crumb firmness of the bread decreased with the addition of the enzyme. The crumb firmness of bread with added xylanase decreased significantly in 24 hours. These results demonstrated that adding sorghum with either xylanase or Pentopan that included xylanase increased specific volume and decreased crumb firmness whereas sorghum decreased the quality of fermented bread when added to wheat flour. The firmness rate of fermented bread particularly decreased with the addition of pure xylanase.

• 한국세라믹학회지
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• 제23권5호
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• pp.1-8
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• 1986

This paper is concerned with a gas sensor composed of semi-conducting ${\gamma}$-$Fe_2O_3$ ceramics made by oxidizing $Fe_2O_3$ sintered body. Acicular $\alpha$-FeOOH powder prepared by precipitation of $FeSO_4$.$7H_2O$ solution was transformed to $FeSO_4$ sintered at 700$^{\circ}$-850$^{\circ}$C for 1 hr. and then oxidized to ${\gamma}$-$Fe_2O_3$ The gas sensitive properties of ${\gamma}$-$Fe_2O_3$ ceramic bodies based on the lectrical resistance change was measured in 0.5-2 vol% $H_2$ and $C_2$ $H_2$ gas at 35$0^{\circ}C$ The specific surface area of sintered specimen largely dependent on the sintering temperature and grain shape directly affected the gas sensitive pro-perties of ${\gamma}$-$Fe_2O_3$gas sensor. Specimens having larger specific surface area showed better sensitivity which means the electrical resistance change due to oxidation and reduction process occurs on ly at the surface of grains microscopically in the ${\gamma}$-$Fe_2O_3$ceramics. Micropores made in $Fe_2O_3$ powder during dehydration of $\alpha$-FeOOH can not prompt the gas sensitive properties of sintered ${\gamma}$-$Fe_2O_3$ because they are sintered or closed in the grains during sintering process and dose not affect the specific surface area of sintered body.

• The Plant Pathology Journal
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• 제37권2호
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• pp.194-199
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• 2021

Blackleg is a serious disease in Brassica plants, causing moderate to severe yield losses in rapeseed worldwide. Although China has not suffered from this disease yet (more aggressive Leptosphaeria maculans is not present yet), it is crucial to take provisions in breeding for disease resistance to have excellent blackleg-resistant cultivars already in the fields or in the breeding pipeline. The most efficient strategy for controlling this disease is breeding plants with identified resistance genes. We selected 135 rapeseed accessions in Sichuan, including 30 parental materials and 105 hybrids, and we determined their glucosinolate and erucic acid content and confirmed 17 double-low materials. A recently developed single-nucleotide polymorphism (SNP) marker, SNP_208, was used to genotype allelic Rlm1/rlm1 on chromosome A07, and 87 AvrLm1-resistant materials. Combined with the above-mentioned seed quality data, we identified 11 AvrLm1-resistant double-low rapeseed accessions, including nine parental materials and two hybrids. This study lays the foundation of specific R gene-oriented breeding, in the case that the aggressive Leptosphaeria maculans invades and establishes in China in the future and a robust and less labor consuming method to identify resistance in canola germplasm.

• 대한환경공학회지
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• 제29권1호
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• pp.74-81
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• 2007

본 연구에서는 케이크 여과 장치의 설계와 케이크 여과 이론의 전개에 가장 큰 역할을 하는 평균 비저항값을 새로운 여과 실험방법인 "여과-투과(filtration-permeation) 실험방법"에 의해 측정하였다. 과거부터 사용되어온 전형적인 여과 실험방법에 의해 측정 되는 평균 비저항값을 여과 평균 비저항 $\alpha_{avf}$이라 하고, 이미 형성된케이크에 입자 제거수를 첨가하여 측정한 평균 비저항값을 투과 평균 비저항 $\alpha_{avf}$이라 하였다. 서로 다른 세 가지 현탁액(입자 현탁액, 응집 현탁액, 고분자 현탁액)에 대해서 "여과-투과 실험방법"으로 케이크 여과를 수행하여 여과기간의 평균 비저항값과 투과기간의 평균 비저항값을 계산하였다. 또한 투과기간의 평균 비저항 값을 기준으로 이론적인 여과과정이 연구되었다. 이 연구결과 입자 여과 조작에서 침전의 영향이 무시될 수 없다는 것이 밝혀졌다. 통상적으로는 침전을 무시하고 있다. 또한 입자 여과과정에서 일정하다고 간주되고 있는 현탁액의 고체분율 5도 변화한다. 통상적인 플럭의 여과과정에서는 케이크 내의 고체분율, $S_c$의 값을 정확히 알기 어렵다는 것을 보였다. 이런 중요한 여러 문제점이 "여과-투과 실험방법"을 통해서는 모두 해결 된다는 것을 보였다.

• Journal of Microbiology and Biotechnology
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• 제21권5호
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• pp.449-454
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• 2011

The infection of pandemic influenza viruses such as swine flu (H1N1) and avian flu viruses to the host cells is related to the following two factors: First, the surface protein such as HA (hemagglutinin) and NA (neuraminidase) of the influenza virus. Second, the specific structure of the oligosaccharide [sialic acid(${\alpha}2$-6) galactose(${\beta}1$-4)glucose or sialic acid(${\alpha}2$-3)galactose(${\beta}1$-4)glucose] on the host cell. After recognizing the specific structure of the oligosaccharide on the surface of host cells by the surface protein of the influenza virus, the influenza virus can secrete sialidase and cleave the sialic acid attached on the final position of the specific structure of the oligosaccharide on the surface of host cells. Tamiflu (oseltamivir), known as a remedy of swine flu, has a saccharide analog structure, especially the sialic acid analog. Tamiflu can inhibit the invasion of influenza viruses (swine flu and avian flu viruses) into the host cells by competition with sialic acid on the terminal position of the specific oligosaccharide on the surface of the host cell. Because of the emergence of Tamiflu resistance, the development of new potent anti-influenza inhibitors is needed. The inhibitors with positive-charge groups have potential as antiviral therapeutics, and the strain specificity must also be resolved.

• 한국건설순환자원학회논문집
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• 제7권3호
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• pp.70-76
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• 2012

ALC의 탄산화를 분석 평가하기 위하여 비중을 0.4, 0.5 및 $0.7g/cm^3$로 제어하였으며, 이중 $0.5g/cm^3$ ALC에 실리케이트 및 실록산계 발수제를 표면 도포하였다. 또한 슬러리에 실리콘 오일 발수제를 첨가하여 ALC를 제조하기도 하였다. ALC의 탄산화는 비중과 밀접한 관련이 있었으며, ALC의 비중이 높아짐에 따라 탄산화도는 감소하였다. 이는 ALC 조직이 치밀할수록 $CO_2$ 가스의 침투가 어려워지기 때문이다. 실리케이트 및 실록산계 발수제를 표면 도포한 ALC에서는 Ref. ALC 보다 탄산화 저항성이 우수하였다. 또한 슬러리에 실리콘 오일을 첨가한 ALC에서 가장 우수한 탄산화 저항성을 나타내었다.