• 한국식품위생안전성학회지
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• 제10권3호
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• pp.133-138
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• 1995

In vitro antimutagenic activity of methanol extract from brrwn rice and its physico-chemical characteristics were investigated using Salmonella typhimurium reversion assay and SOS chromotest. Methanol extracts of brown rice were not mutagenic compared with direct and indirect, mutagenicities of 4NQO (4-nitroquinoline oxide), 2NF(2-nitrofluorene), Trp-p-1(3-Amino-1,4-dimethyl-5H-pyrido-[4,3-b]indole), and Trp-p-2(3-Amino-1-methy-5H-pyrido-[4,3-b]indole). Antimutagenic activity against the indirect mutagenicties induced by Trp-p-1, Trp-p-2 and AFB1 (aflatoxin B1) was found in methanol extract. Even though antimutagenic activity showed dose-dependent, it remained constant at inhibition rate ranging 60~90% when the concentration was abov 3mg/plate in the S. typhimurium reversion assay and 0.2~0.6 mg/assay in the SOS chromotest. The antimutagenic activity of the methanol extracts was stable at various pH (2, 7 and 10), temperatures (60, 80 and 10$0^{\circ}C$)and heation times (2, 4, 6, 8, 10 min at 10$0^{\circ}C$).

• Animal Bioscience
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• 제37권8호
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• pp.1474-1482
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• 2024

Objective: The experiment aimed to determine the standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in 10 brown rice samples fed to pigs, and to construct predictive models for SID of CP and AA based on the physical characteristics and chemical composition of brown rice. Methods: Twenty-two cannulated pigs (initial body weight: 42.0±1.2 kg) were assigned to a replicated 11×3 incomplete Latin square design, including an N-free diet and 10 brown rice diets. Each period included 5 d adaptation and 2 d ileal digesta collection. Chromic oxide was added at 0.3% to all the diets as an indigestible marker for calculating the ileal CP and AA digestibility. Results: The coefficients of variation of all detected indices for physical characteristics and chemical composition, except for bulk weight, dry matter (DM) and gross energy, in 10 brown rice samples were greater than 10%. The SID of CP, lysine (Lys), methionine, threonine (Thr), and tryptophan (Trp) in brown rice was 77.2% (62.6% to 85.5%), 87.5% (80.3% to 94.3%), 89.2% (78.9% to 98.9%), 55.4% (46.1% to 67.6%) and 92.5% (86.3% to 96.3%), respectively. The best prediction equations for the SID of CP, Lys, Thr, and Trp were as following, SID_CP = -664.181+8.484×DM (R² = 0.40), SID_Lys = 53.126+6.031×ether extract (EE)+0.893×thousand-kernel volume (R² = 0.66), SID_Thr = 39.916+7.843×EE (R² = 0.41), and SID_Trp = -361.588+4.891×DM+0.387×total starch (R² = 0.85). Conclusion: Overall, a great variation exists among 10 sources of brown rice, and the thousand-grain volume, DM, EE, and total starch can be used as the key predictors for SID of CP and AA.

• 대한환경공학회지
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• 제32권6호
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• pp.547-554
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• 2010

본 연구에서는 나노구조의 새로운 망간산화물 입자(즉, 블랙-버네사이트)를 합성하여 물질특성 및 1,4-naphthoquinone (1,4-NPQ)을 대상으로 반응매개체 존재 하에서의 산화-변환반응 효율을 조사하였고, 그 결과를 기존의 McKenzie 방법으로 얻은 망간산화물(즉, 브라운-버네사이트)의 결과와 비교 분석하였다. XRD 분석 결과 합성한 망간산화물 입자의 결정상은 버네사이트(${\delta}-MnO_2$)임을 확인하였으며, SEM 측정결과 입자표면은 섬유상의 구조에 의한 나노크기의 미세기공을 가진 볼모양(ball-like)의 형태를 보였다. 배치실험 결과, 나노구조의 망간산화물에 의한 1,4-NPQ 제거는 유사-1차 반응을 따랐으며 기존 망간산화물과 비교해 BET 비표면적 값이 작음(41.05 vs 19.80 $m^2/g$)에도 불구하고 약 2.3배의 높은 속도 상수값을 보였다. 이러한 결과는 블랙-버네사이트에서의 상대적으로 높은 결정성과 나노구조의 표면 특성에 기인한 것으로 해석되며, 블랙-버네사이트 입자가 퀴논화합물에 대하여 상대적으로 높은 반응성을 보임을 알 수 있다. 반응산물에 대한 HPLC 크로마토그램 분석 결과로부터 블랙 버네사이트 입자에 의한 1,4-NPQ의 제거는 반응 매개체인 catechol 존재 하에서의 상호-결합반응을 통한 중합체 생성을 통해 제거됨을 확인하였다.

• Fisheries and Aquatic Sciences
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• 제17권1호
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• pp.27-35
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• 2014

Marine brown algae have been identified as a rich source of structurally diverse bioactive compounds. Whether Myagropsis yendoi ethanolic extracts (MYE) inhibit inflammatory responses was investigated using lipopolysaccharide (LPS)-stimulated microglia BV-2 cells. MYE inhibited LPS-induced nitric oxide (NO) production in a dose-dependent manner and suppressed the expression of inducible nitric oxide synthase in BV-2 cells. MYE also reduced the production of pro-inflammatory cytokines in LPS-stimulated BV-2 cells. LPS-induced nuclear factor-${\kappa}B$ (NF-${\kappa}B$) transcriptional activity and NF-${\kappa}B$ translocation into the nucleus were significantly inhibited by MYE treatment through preventing degradation of the inhibitor ${\kappa}B-{\alpha}$. Moreover, MYE inhibited the phosphorylation of AKT, ERK, JNK, and p38 mitogen-activated protein kinase in LPS-stimulated BV-2 cells. These results indicate that MYE is a potential source of therapeutic or functional agents for neuroinflammatory diseases.

• 마이크로전자및패키징학회지
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• 제6권2호
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• pp.1-12
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• 1999

Brown oxide and/or black oxide layers were formed on the surface of Cu-based leadframe by chemical oxidation of leadframe in hot alkaline solutions, and their growth characteristics were studied. Then, to measure the adhesion strength between leadframe and epoxy molding compound (EMC), oxidized leadframe samples were molded with EMC and machined to form sandwiched double-cantilever beam (SDCB) specimens and pull-out specimens, respectively. Results showed that the adhesion strength of un-oxidized leadframe/EMC interface was inherently very poor but could be increased drastically with the nucleation of acicular CuO precipitates on the surface of leadframe. The presence of smooth faceted $Cu_2O $ on the surfaces of leadframe gave close to zero interfacial fracture toughness (Gc) and reasonable pull strength (PS). A direct correlation between Gc and PS showed that PS can be a measure of Gc only in a limited range.

• 한국분말재료학회지
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• 제31권4호
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• pp.336-341
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• 2024

Molybdenum, valued for its high melting point and exceptional physical and chemical properties, is studied in diverse fields such as electronics, petrochemicals, and aviation. Among molybdenum oxides, molybdenum dioxide stands out for its higher electrical conductivity than other transition metal oxides due to its structural characteristics, exhibiting metallic properties. It is applied as pellets to gas sensors, semiconductors, and secondary batteries for its properties. Thus, research on molybdenum dioxide compaction and pressureless sintering is necessary, yet research on pressureless sintering is currently insufficient. This study synthesized MoO₃ powder via solution combustion synthesis and reduced it using the 3% hydrogen/argon gas mixture to investigate the effect of reduction temperature on the powder. Additionally, the reduced powder was compacted and subjected to pressureless sintering with temperature as a variable. The density and the microstructure of brown parts were analyzed and discussed.

• Journal of Applied Biological Chemistry
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• 제56권4호
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• pp.249-255
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• 2013

Recently, algae has been considered as a potential anti-inflammatory source due to its distinctive habitat environment exposing to light and high oxygen concentration. In present study, anti-inflammatory effect of brown alga, Sargassum fullvellum ethanol extract (SFEE), was examined. SFEE inhibited not only the production of nitric oxide and pro-inflammatory cytokines (IL-6, IL-$1{\beta}$, TNF-${\alpha}$) but also the expression of inducible nitric oxide synthase and cyclooxygenase 2 in LPS-induced RAW 264.7 cells without affecting cell viability. SFEE also suppressed the expression of nuclear factor kappa B (NF-${\kappa}B$), suggesting that SFEE could affect the expression of inflammation related cytokines and proteins through the regulation of NF-${\kappa}B$. Furthermore, formation of edema of the ear was 40% lower in mice treated with the highest dose (250 mg/kg) of SFEE than in the control mice. Thus, our study showed that SFEE may be a potential therapeutic anti-inflammatory drug.

• 한국응용과학기술학회지
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• 제31권2호
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• pp.176-182
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• 2014

Using alkali treatment solution, neutrality treatment solution and acid treatment solution, the surface corrosion layer of copper plates and bronze plates that have been artificially corroded using HCl, $H_2SO_4$ and $HNO_3$ solutions were removed. In the case of alkali treatment solution, only air oxidation in the form of black tenorite and white cuproous chloride remained without being removed. In the case of using a neutrality treatment solution, a anhydrous type layer of reddish brown cupric chloride remained without being removed, together with this black and white corrosion substance. In the case of using an acid treatment solution, this red corrosion substance also remained, but all of the oxide was removed on the surface of the specimen that was treated by alternatively using alkali treatment solution and acid treatment solution. In the case of this treatment solution with the order of alkali-acid, oxidation no longer proceeded only through the distilled water cleaning process after treatment, thereby showing that oxidation from the cleaning solution no longer proceeded.

• 한국진공학회지
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• 제13권4호
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• pp.145-149
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• 2004

RF magnetron sputtering 방법으로 miscut된 기판을 이용해서 양질의 압전 산화물 에피 박막을 제작하였다. 박막은 (001) $SrTiO_3$ 기판 위에 증착되었으며, (100) 방향으로 $0^{\circ}$-$8^{\circ}$의 miscut 각도를 갖는 기판들을 사용했다. $4^{\circ}$이상의 큰 miscut 각도를 갖는 기판 위에 성장된 박막의 경우, x-ray diffraction (XRD) 패턴은 perovskite 상의 순수한 PMN-PT 피크만을 보여 주었으며, wavelength dispersive x-ray fluorescence spectroscopy를 이용해서 분석한 조성비는 stoichiometric한 조성비에 가까운 값을 보여주었다. 반면에, miscut 각도가 없는 기판 위에 증착된 박막의 경우, 2차상인 pyrochlore 상을 포함하는 XRD 패턴을 보여주었다. $8^{\circ}$ 기판 위에 성장된 박막의 경우 실온에서 20$\mu$C/$\textrm{cm}^2$라는 높은 잔류분극 값을 보여주었다

• 자원환경지질
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• 제46권5호
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• pp.445-453
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• 2013

의성 탑리리 오층석탑(국보 제77호)은 통일신라시대의 대표적인 석조문화재이다. 현재 이 석탑은 지속적인 풍화로 인해 전체적으로 흑색, 황색, 백색변색이 발생되어 있으며 백색변색이 발생한 부분에서 미세균열, 박리박락, 입상분해가 집중적으로 분포해 있다. 표면오염물에 대한 분석결과, 흑색변색은 망간산화물, 황색변색은 철산화물, 백색변색은 석고와 타라나카이트로 인해 발생한 것으로 확인하였다. 또한, 석탑에 발생한 물리적 훼손은 암석내부에서 석고의 결정화 작용으로 인해 발생한 것으로 판단된다. 따라서 의성 탑리리 오층석탑을 장기적으로 보존하기 위해서는 보존처리 매뉴얼에 따라 석고를 중심으로 표면오염물을 제거하고 P-XRF를 활용한 정기적인 모니터링이 요구된다.