• Kyungpook Mathematical Journal
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• 제43권4호
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• pp.495-497
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• 2003

Let ${\wp}_1$, ${\wp}_2$ be the radical classes of rings. Y. Lee and R. E. Propes have defined their sum by ${\wp}_1+{\wp}_2=\{R{\in}{\omega}:{\wp}_1(R)+{\wp}_2(R)=R\}$. They have shown that ${\wp}_1+{\wp}_2$ is not a radical class in general. In this paper, a few results of Lee and Propes are generalized and also new conditions are investigated under which this sum becomes a radical class.

• Environmental Engineering Research
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• 제10권1호
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• pp.38-44
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• 2005

Electro-thermal production of white phosphorus(WP, P4) generates substantial amount of highly toxic phossy water and sludges. Because of their high phosphorus contents and lack of reliable processing technology, large tonnages of these hazardous wastes have accumulated from current and past operations in the United States. In this study, two different methods for treatment of phosphorus sludge were investigated. These were bulk removal of WP by physical separation(froth flotation) and transformation of WP to oxyphosphorus compounds by air oxidation in the sludge medium. Kerosene, among other collectors, resulted in selective flotation of WP from the associated mineral gangue. Solvent action of kerosene occurring on the WP surface(by rendering WP particles hydrophobic) might produce the high selectivity of WP. The WP recovery in the froth was 79.3% from a sludge assaying 34.2% of WP. In the oxidation study, air gas was dispersed in the sludge medium by the rapid rotation of the impeller blades. The high level of sludge agitation intensity caused a fast completion of the oxidation reactions and it resulted in the high percentage conversion of WP to PO4-3 with PO3-3 making up almost all portion of oxyphosphorus compounds. The WP analysis on the treated sludge showed that supernatant solution and solid residue contained an average of 4.2 μg/L and 143 ppm respectively from the sludge containing about 26 g of WP. Further investigation will be required on operational factors to better understand the processes and achieve an optimum condition.

• 한국응용곤충학회지
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• 제15권3호
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• pp.127-132
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• 1976

수도 수묘형 육묘에 있어서 종자침하에 의한 부패, 발아지연, 종자의 부유에 의한 종자가 한쪽으로 몰리는 등의 해를 야기시켜 발아율이나 성묘율율 저하시키는 조류나 괴불방제를 시도하여 수묘대에서 파종전후 5일에 Cuperic Sulfate, Lime Sulfur, Swep 80wp. Dithane A-40, Dichlone 50wp를 처리하여 다음과 같은 결과를 얻었다. 1. 조류 및 괴불방제의 효과가 뚜렷한 약제는 Dichlon 50.wp, Dithane A-40, Swep 80 wp 였으나 Dithane A-40, Swep 80wp는 약해등으로 성묘율이 낮었다. 2. Cuperic Sulfate는 조류 및 괴블에 대한 약제효과는 인정되었으나 약제처리후의 파종시 발아억제 및 종자침하현상이 심하였다. 3. 파종후 25일묘 조과결과 Dichlone 50wp를 제외한 기타 약제처리구는 Check구에 비하여 지하부의 근수, 지상부의 생체중 및 건물중비율이 낮았고 초장은 약제처리구가 전반적으로 낮은 편이었다. 4. Dichlone 50wp는 조류 및 괴블 방제효과 과 뚜렷하여 종자발아 및 성묘비율을 높일 수 있었으며 약효의 지속기간은 처리후 4일 정도임이 인정되었다.

• 전기전자학회논문지
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• 제22권2호
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• pp.393-401
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• 2018

이 논문에서는 WPC / A4WP 무선 전력 전송을 위한 정류기가 설계하였다. 설계된 정류기는 WPC (무선 전력 컨소시엄) 및 A4WP (무선 전력 연합)를 모두 지원하며 전파 브리지 정류기로 설계되었다. WPC는 100kHz ~ 205kHz의 주파수에서 전력을 전송하고 A4WP는 6.75MHz의 주파수에서 전력을 전송한다. 브리지 정류기는 다이오드 대신 MOSFET을 사용하기 때문에 출력 전압이 입력 전압보다 높으면 역전류가 흐르고 효율에 영향을 미친다. 따라서 MOSFET을 통해 흐르는 전류를 감지하고 역전류를 차단하는 역전류 검출기를 추가했다. 주파수 판별기는 주파수 대역이 다르기 때문에 사용된다. 설계된 정류기는 CMOS $0.35{\mu}m$ 고전압 공정을 사용하여 설계되었다. 입력 전압은 최대 18V이며 100kH ~ 205kHz, 6.78MHz 주파수에서 작동한다. 최대 효율은 94.8 %이고 최대 전력 공급은 5.78W 이다.

• Journal of Dairy Science and Biotechnology
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• 제30권2호
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• pp.93-109
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• 2012

This study was performed to investigate the effects of added whey protein concentrates (WPC) and whey powder (WP) on the quality and shelf life of Tofu, a traditional food in Korea. Combined whey powder and whey protein concentrates were obtained at drainage after the casein was separated by using rennet enzyme or acidification of milk. We manufactured whey Tofu and evaluated its nutritional quality by testing, the general composition for yield, moisture, pH, crude protein, crude fat, carbohydrate, rheology, sensory properties, and change during storage. 1. The general compositions of WPC and WP were as follows: (a) WPC: moisture, 5.9%; crude protein, 56.2%; crude fat, 0.1%; carbohydrate, 32.6%; ash, 5.2%; and pH 5.93 and (b) WP: moisture, 3.7%; crude protein, 13.2%; crude fat, 1.6%; carbohydrate, 74.4%; ash, 7.1%; and pH, 6.65. 2. The yield of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=8:2 and (b) in WP, 2% addition was the highest (265%) at $13.3g/cm^2$, but with 4% addition WP was the lowest (184%) at $22.2g/cm^2$. 3. The moisture content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL = 6:4 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=8:2 and (b) in WP, 2% addition was the highest at 79.82% ($13.3g/cm^2$), but 4% was the lowest at 75.18% ($22.2g/cm^2$). 4. The pH of Tofu was as follows: (a) in WPC, the value was WPC 6% > WPC 4% > WPC 2% > control and $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 and (b) in WP, WP 4% > WP 2% > control. 5. The ash content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 and (b) in WP, there was no difference between 2% and 4% addition. 6. The crude protein content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=6:4 and (b) in WP, there was no difference between 2% and 4% addition. 7. The crude fat content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=6:4 and (b) in WP, values decreased with increasing pressed weight. 8. The carbohydrate content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 and (b) in WP, values increased with increasing pressed weight. 9. The rheology test results of Tofu were as follows: (a) in WPC, hardness and brittleness was highest with $CaCl_2$:GDL=8:2 and 6% added WPC. Cohesiveness was highest with $CaCl_2$:GDL=6:4 and 2% added WPC. Elasticity was the highest with $CaCl_2$:GDL=7:3 and the added WPC control. (b) in WP, hardness was the highest with $22.2g/cm^2$ and added WP control. Cohesiveness was the highest with $17.8g/cm^2$ and added WP 2%. Elasticity was the highest with $17.8g/cm^2$ and added WP 4%. Brittleness was the highest with $17.8g/cm^2$ and added WP control. 10. The sensory test results of Tofu were as follows: (a) in WPC, the texture, flavor, color, and smell were the highest with $CaCl_2$:GDL=6:4 and 6% added WPC. (b) in WP, the texture was the highest in the control with $22.2g/cm^2$. Flavor and smell were the highest in WP 2% and $22.2g/cm^2$. Color was the highest in WP 2% and $17.8g/cm^2$. 11. The quality change of Tofu during storage was as follows: (a) in WPC, after 60 h, all samples began to get spoiled and their color changed, and mold began to germinate. (b) in WP, the result was similar, but the rate of spoilage was more rapid than that in the control.

• KSBB Journal
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• 제16권5호
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• pp.486-492
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• 2001

숙지황 물추출물로부터 분리된 fraction(RG-III) 의 항돌연변이원성의 기작을 E. coli GW, B/r 균주를 이용하여 조사하였다. SOS 유도를 반영하는 $\beta$-galactiosidase 활성이 E. coli GW 1060, 1103, 1107, 1105에서 증가되지 않았다. RG-III는 RecA는 단백질의 합성을 증폭시키거나 LexA 산물의 분해를 저해하지 않았으므로 SOS en 기능의 발현이 영향을 미치지 못했다. 따라서 DNA 수복의 경로가 다른 E. coli B.r 변이주를 사용하여 4NQO와 MNNG에 대한 세포내 항돌연변이원성과 생존효과를 조사하였다. ZA159(uvrB, 최)를 제외한 WP2, WP2s, WP67, CM561, CM611에서 RG-III는 4NQO에 대한 생존력을 미약하게나마 증가시켰으나, 이러한 생존력 재활성을 수복모드에 의해 설명할 수 없었다. WP2, WP2s, WP67, CM561, CM611에서 RG-III는 MNNG로 유도된 돌연변이원성과 치사력을 증가시킴에도 불구하고 ZA159(uvr B, chl)에서는 감소시켰다. 4NQO의 변이원성을 두드러지게 억제하였으나 ZA159(uvr B, chl)에서 상승효과가 상대적으로 감소되었다. 이러한 결과들은 RG-III가 4NQO의 변이원성을 방어하는 차단제임을 시시하여, chl 산물의 기능과 유사한 작용을 하는 것으로 사료된다.

• 한국균학회지
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• 제49권1호
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• pp.87-100
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• 2021

많은 사람들이 다녀가는 도시공원과 해변 환경의 효모 특성을 알아보기 위해 대전광역시 월평공원 갑천 누리길과 내원사 주변의 야생화와 토양 75점에서 모두 88균주의 야생 효모들을 분리, 동정하였다. 또한 전북 부안의 격포해수욕장과 격포항 주변 야생화와 토양 35점에서 30균주의 야생 효모들을 분리하였다. 이들 분리 야생 효모들 중 A. porosum ASCM32-1, A. scarabaeorum WP49-1, C. athensensis WP4-90-3, C. berkhoutiae WP34-2, C. bracarensis WP35-1, Cy. amylophila GP19-1, K. gamospora WP9-1, M. carpophila BN-17-1, T. namnaoensis WP4-89-1, V. taibaiensis WP13-2 등 10종의 국내 미기록종 후보 균주들을 선별하여 균학적 특성을 확인하였다. 이들 미기록 효모들은 주로 구형~타원형으로 모두 출아방식으로 영양 증식을 하였고 V. taibaiensis WP13-2와 K. gamospora WP9-1, C. athensensis WP4-90-3 외 7종의 미기록 효모들은 자낭포자를 형성하지 않은 무포자 효모들이었으며A. porosum ASCM32-1만이 의균사를 생성하였다. 대부분의 균주들은 YPD 배지와 YM 배지에서생육하였고V. taibaiensis WP13-2와K. gamospora WP9-1, T. namnaoensis WP4-89-1 균주들은 15% NaCl을 함유한 YPD 배지에서 생육하는 호염성 효모들이었고, Cy. amylophila GP19-1 균주는 40℃에서도 생육하였다. C. athensensis WP4-90-3 균주 등 5균주들이 10% 에탄올 내성을 보였고C. athensensis WP4-90-3 균주는 Li²⁺ 등 많은 중금속들에 대해서 내성을 보였다. 국내 미기록 효모들과 비병원성 야생 효모 균주 무세포추출물들의 β-glucuronidase 저해 활성은 C. oleophila WP5-19-1의 무세포 추출물이 49.0%로 가장 높았고 미기록 효모인 K. gamospora WP9-1의 무세포 추출물도 27.7%를 보였다. 호중구 elastase 저해 활성은 W. anomalus HO9-2가 38.4%로 우수하여 건강 소재로 생산에 매우 유용한 균주로 활용될 것으로 기대된다.

• TTA 저널
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• 통권81호
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• pp.151-156
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• 2002

• 한국표면공학회지
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• 제35권6호
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• pp.377-382
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• 2002

We investigated the appropriate wet cleaning process for Co-Ti-Si compounds formed on top of cobalt disilicide made from Co/Ti deposition and two rapid thermal annealing (RTA). We employed three wet cleaning processes, WP1 ($H_2$SO$_4$ etchant), WP2 ($NH_4$OH etchant), and WP3 which execute sequentially WP1 and WP2 after the first RTA. All samples were cleaned with BOE etchant after the second RTA. We characterized the sheet resistance with process steps by a four-point probe, the microstructure evolution by a cross detail sectional transmission electron microscope, a Auger depth profiler, and a X-ray diffractometer (XRD). We confirmed WP3 wet cleaning process were the most suitable to remove CoTiSi layer selectively.

• 한국축산식품학회지
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• 제33권4호
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• pp.448-455
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• 2013

Proper storage of left-over meat in a household refrigerator is important for extending its shelf-life and assuring its safety until it is next used. Various fresh meat packaging methods were examined to determine their effects on the quality characteristics of pork loins during household storage at $5^{\circ}C$. The packaging methods include 1) wrapping in a polyethylene pouch (WP), 2) keeping in an air-tight plastic container (CP), and 3) using a household vacuum packaging machine (VP). The fastest increase in total aerobic bacteria during storage occurred in the WP samples, followed by the CP and VP samples. The count of Pseudomonas spp. was found to be lowest in the VP, and then the CP and WP samples. Enterobacteriaceae grew fastest in the WP samples, followed by the CP and VP samples. The WP samples also incurred the most significant increase in thiobarbituric acids and volatile basic nitrogen values over the storage period, as compared to the CP and VP samples. Off-odour at 30 min after opening the package, was first notable at day 11 in WP samples, but only at day 15 in the CP and VP samples. The colour also deteriorated earlier in the WP samples than in the CP and VP samples.