• 호남수학학술지
• /
• 제28권3호
• /
• pp.377-386
• /
• 2006

For a commutative ring with unity R, it is proved that R is a PF-ring if and only if the annihilator, $ann_R(a)$, for each $a{\in}R$ is a pure ideal in R. Also it is proved that the polynomial ring, R[x], is a PF-ring if and only if R is a PF-ring. Finally, we prove that M as an R-module is PF-module if and only if M[x] is a PF R[x]-module. Also M is a PP R-module if and only if M[x] is a PP R[x]-module.

• 한국가축번식학회지
• /
• 제15권3호
• /
• pp.221-224
• /
• 1991

This study was undertaken to evaluate the effect of rabbit peritioneal fluid(rPF) on in vitro maturtion of porcine follicular oocytes. From does 20h after hCG injection, rPF was aspirated aseptically at laparatomy, and then centrifuged, filtrated, and preincubated immediately for 12h. Porcine follicular oocytes isolated from ovaries of slaughtered animals were incubated in TCM-HEPES＋10% FCS, TCM-HEPES＋rPF(v/v, 50/50), or rPE only and examined the nuclear maturation after aceto-orcein or hochest staining. After identifying the optimal incubation time, this experiment was repeated for 5 times. Under the TCM-HEPES containing hormones and serum codition, the time range of porcine follicular oocyte maturation was 38 to 44 hours and the optimal time of maturation of follicular oocyte in vitro was 42 hour cultivation, respectively. The maturatin rates(89.4% and 92.7%) of porcine follicular oocytes cultured in the media with 50% rPF or only rPF were signifciantly higher thanthat (84.6%) of oocytes cultured with TCM-HEPES, respectively. These results suggest that the unknown components(s) of rPF promoted in vitro maturation of porcine follicular oocytes.

• 한국가구학회지
• /
• 제12권2호
• /
• pp.29-38
• /
• 2001

This study was carried out to develope a new process of flattening bamboo pieces(3 months old) by two steps of utilizing microwave oven and hot press. Internode bamboo pieces were impregnated with low molecular weight phenol formaldehyde resin (PF) under vacuum of 76 cmHg, heated in a household microwave oven in 1 minute, pressed on the temperature of $145^{\circ}C$ by the hot press for 10 minute, and then cooled by the cold press in their flattened form. The physical and mechanical . Properties of compressed flattened bamboo were as follows: 1) PF1(Mw:427) and PF2(Mw:246) sol. met the success of flattening of internode bamboo pieces in both of P. bambusoides and P. nigra var. PF2 showed the more plasticity to flatten the bamboo than PFI. The PF2 sol. with low molecular weight(Mw:246) gave the more weight gain than that of PF1 in the equal concentration. PF1 of 5% (NVC) and PF2 of 10% (NVC) sol. gave the best result for physical and mechanical properties and from a economical view point. 2) The PFI of 5% (NVC) sol. with low molecular weight decreased the water absorption of 62-63% and increased the bending strength (MaR) of 80-90%, compression strength of 43-54%. 3) The PF2 of 10% (NVC) sol. with low molecular weight decreased the water absorption of 56-57% and increased the bending strength (MaR) of 64-86%, compression strength of 39-63%.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제35권2호
• /
• pp.63-70
• /
• 2017

Native fluorescent pseudomonas bacteria were isolated from rhizosphere soil of mulberry and were evaluated against powdery mildew. In vitro conidial germination study showed significant (P<0.05) variation in conidial germination by bacterial strains Pf1 and Pf3. Mildew incidence was significantly varied due to treatment with various pseudomonas strains in vivo. Significantly (P<0.05) less mildew incidence was in plants treated with the bacterial strain Pf1 (9.11%) followed by Pf3 (13.48%) controlling 69.40% and 54.75% respectively compared with untreated control. Similarly, mildew severity was least (8.51%) in plants treated with strain Pf1 followed by Pf5 (9.23%) and Pf3 (9.72%) controlling the severity by 84.51%, 77.01% and 71.96% respectively compared with control. The bacterial strains significantly influenced biochemical constituents such as chlorophyll, protein and soluble sugar content of the mulberry leaf. Similarly, bacterial strains significantly increased the activity of the peroxidase (PO) and Polyphenol oxydase (PPO) activity from $7^{th}$ day up to the $28^{th}$ day after treatment. The strain Pf1, Pf3 and Pf5 exhibited a marked enhancement in the peroxidase at different periods of infection. Significant (P<0.01) negative correlation was found between powdery mildew severity with phenol content ($R^2=0.67$) as well as peroxidase ($R^2=0.92$) and polyphenol oxidase ($R^2=0.72$) activity thus confirms induction of systemic resistance in mulberry by pseudomonas bacteria. The study shows scope for exploration of rhizosphere fluorescent pseudomonas bacteria for induction of systemic resistance in mulberry to contain powdery mildew disease effectively.

• 한국산학기술학회논문지
• /
• 제21권9호
• /
• pp.57-63
• /
• 2020

말 정자의 첨체 손상도를 간단하게 분석하는 기술을 개발하기 위하여 Coomassie brilliant blue G 또는 R 염색 시약을 이용하여 정자 도말 슬라이드에 대한 염색도를 조사하였고, 3.7% paraformaldehyde (PF)과 35% methanol (MT) 고정제가 첨체 염색에 미치는 영향을 연구하였다. PF로 고정한 후 말 정자 도말 슬라이드를 0.05, 0.1 및 0.2 % 농도 CBB에 각 2분간 염색을 실시하여 첨체를 관찰하면 0.05%의 경우 완전한 첨체 염색도가 G형에서 62.6%, R형은 61.5%로 관찰되었으나, 0.1 및 0.2%의 경우, 80.2 및 79.7%로 (G 형), 78.1 및 76.0%로 (R 형) 관찰되어 유의적 차이가 나타났다. 그러나 MT 고정제를 이용할 경우, 첨체 외막이 느슨해진 정자의 비율은 3.5%로 관찰되어 PF 고정제를 사용하면 9.0%로 관찰되어 유의적으로 낮게 관찰되었다. 이러한 결과는 말정자첨체손상도를 관찰하기 위하여 CBB G 또는 R형 염색시약을 0.1~0.2% 농도로 이용될 수 있음을 증명한다. 또한, 말 정자 슬라이드 도말을 고정하는데 있어 고정제의 선택이 중요하며 MT보다 PF를 활용하는 것이 첨체 변화 과정 중인 정자를 관찰하는데 중요하다는 보여 준다. 이러한 방법은 말의 인공수정을 위한 정액의 저온저장 또는 동결보존과정 중에서 정자첨체손상율을 정확하게 판별하는데 이용될 수 있음을 증명한다.

• Kyungpook Mathematical Journal
• /
• 제47권1호
• /
• pp.127-132
• /
• 2007

In this paper, we show that if R is a commutative ring with identity and (S, ${\leq}$) is a strictly totally ordered monoid, then the ring [[$R^{S,{\leq}}$]] of generalized power series is a PF-ring if and only if for any two S-indexed subsets A and B of R such that $B{\subseteq}ann_R(|A)$, there exists $c{\in}ann_R(A)$ such that $bc=b$ for all $b{\in}B$, and that for a Noetherian ring R, $[[R^{S,{\leq}}$]] is a PP ring if and only if R is a PP ring.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2006년도 전력전자학술대회 논문집
• /
• pp.435-437
• /
• 2006

KSTAR (Korea Superconducting Tokamak Advanced Research) 장치는 Tokamak 개념의 핵융합 연구 장치로서 플라즈마를 가두기 위한 자장을 발생하는 토로이달 자장(Toroidal Field, TF) 코일과 플라즈마 발생 및 형상 조정을 위한 폴로이달 자장 (Poloidal Filed, PF) 코일로 구성되며, 초전도 코일을 이용한다. TF코일의 전원장치로는 40 kA급의 안정된 직류 전원장치가 필요하며, PF 코일의 전원장치로는 빠른 전류상승 및 피드백 기능을 갖춘 정밀 대전류 전원을 필요로 한다. 또한 초전도 코일의 ??????치현상 발생 시 코일과 전원장치 보호를 위한 대전류 직류 차단시스템을 필요로 한다. KSTAR 장치의 설계에 의하면 상하 7쌍의 초전도 PF 코일에 약 1MA/sec급의 고속 전류구동을 운전 시나리오에 따라 인가하여 핵융합 연구를 위한 플라즈마를 생성한다. 본 논문은 TF 및 PF 코일에 대전류를 인가하기 위해서 개발된 전원장치 (Power Supply, PS)에 관한 연구이다.

• 한국전기화학회:학술대회논문집
• /
• 한국전기화학회 2004년도 춘계총회 및 학술발표회
• /
• pp.54-54
• /
• 2004

• 대한본초학회지
• /
• 제26권3호
• /
• pp.37-45
• /
• 2011

Objectives : This study focused on Schisandrae Fructus (SF) and Perilae Folium (PF), traditional medicine herbs and health functional food in Korea, Japan and China. We investigated various pharmacological activities that include a potential source of free radical scavenging, anti-viral, anti-microbial, anti-allergy and anti-inflammatory activities. Methods : We conducted an investigation of total contents of phenolic and flavonoid compounds in these single herbal extraction with/without combined to mixture. We also measured antioxidant activities such as DPPH free radical scavenging, SOD-like scavenging, nitrite scavenging and hydroxyl radical scavenging activities, xanthine oxidase inhibition, linoleic acid peroxidation inhibition, and reducing power. Results : As the results, contents of total phenoilc compounds and flavonoids were higher in those of PF than those of SF. Those of SF+PF mixture showed the synergy effects compared with those of SF and PF single extractions. Activities of DPPH free radical and SOD-like scavenging in 1 mg/mL concentration increased in dose dependent manners. That of SF increased compared with that of PF. That of SF and PF mixture also increased compared with that of BHA as a positive control. The other antioxident activities also showed similar to patten of activity of DPPH free radical scavenging. When combined to SF and PF extractions, there was showed synergic effect compared with those of BHA, excepted activities of xanthine oxidase inhibition and reducing power. Taken together, SF and PF have high phenolic and flavonoid compounds content furthermore, antioxidant activities in SF and PF mixture showed more synergy effect compared with those of BHA. Conclusions : Therefore, these findings suggest that SF and PF mixture may offer functional materials potential for development of functional beverage. But further studies are needed for the identification of the active compounds.

• 약학회지
• /
• 제46권5호
• /
• pp.337-342
• /
• 2002

Propofol(2,6-diisopropyl phenol) is a phenol derivative that is chemically distinct from other intravenous sedative hypnotics. It has been extensively used as a short term anesthetic agent, because of the rapid onset and short duration of action. Propofol microemulsion system was prepared with different concentrations of ethyl oleate, $Solutol^{(R)}$ HS 15 and $Kollidon^{(R)}$ 17 PF. Propofol microemulsions were studied by transmittance, viscosity, particle size, in vitro release and pharmacokinetics. The range of transmittance of A group with 4% ethyl oleate and that of B group with 5% ethyl oleate were 92.6~95.1 and 91.3~94.2%, respectively. Transmittance 1~2% decreased as concentration of $Kollidon^{(R)}$ 17 PF was increased and increased 0.8~3.3% when 10 times diluted with normal saline. The viscosity of A and B group were in the range of 3.9~4.1 mPaㆍsec and 4.4~5.3 mPaㆍsec, respectively. The particle sizes of A and B group increased as amount of $Kollidon^{(R)}$ 17 PF. Also, release of propofol was slowly increased as the amount of $Kollidon^{(R)}$ 17 PF was increased. Propofol plasma concentration by i.v injection showed 2-compartment model. Pharmacokinetics of A-5 was similar to that of commercial emuision(POFOL).