• 한국환경성돌연변이발암원학회지
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• 제22권2호
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• pp.106-111
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• 2002

AG6O, the complex of acriflavine and guanosine, has been shown to possess the synergistic antitumorigenic activity in the previous paper (J. Pharm. Pharmacol. 1997, 49:216). In this study, we have investigated the genotoxic properties of AG60 using in vitro and in vivo system such as Ames bacterial reversion test, chromosomal aberration assay and micronucleus assay. In Ames reverse mutation test, AG60 treatment at the dose range up to 250 $\mu\textrm{g}$/plate caused the dose-independent random induction of the mutagenic colony formation in S. typhimurium TA98, TA100, TA1537, and E. coli WP2uvrA, while any mutagenic effect of AG60 wasn't observed in S. typhimurium TA1535. Any significant chromosomal aberration wasn't observed in chinese hamster lung (CHL) fibroblast cells incubated with PBS or AG60 at the concentrations of 2.5, 5, 10 $\mu\textrm{g}$/$m\ell$ for 24 hours without but even with 59 metabolic activation system for 6 hours. In vivo ICR mice, the intramuscular injection of AG60 at the doses of 7.15, 14.3, and 28.6 mg/kg did not induce the frequency of micronucleus formation. However, mitomycin C, as one of the positive controls at the dose of 2 mg/kg caused the 8.4% induction in the frequency of micronucleus and 24% increase in the chromosomal aberration.

• 한국초전도ㆍ저온공학회논문지
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• 제5권3호
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• pp.6-10
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• 2003

Silver nano-powder was added to Ma $B_2$ to make (Ag)$_{(x)wt.%}$(Mg $B_2$)$_{(l00-x)wt.%}$ (A $g_{x}$-Mg $B_2$) (10 $\leq$ x $\leq$ 50) composite superconductors to investigate the effect of the Ag nano-powder on the vortex pinning. Pellets made out of the mixed powder were put inside stainless steel tubes, which were sintered at 85$0^{\circ}C$ in Ar atmosphere. No impurity phase was identified for as-rolled samples. However, both the Mg $B_2$ and the A $g_{x}$-Mg $B_2$ composite pellets, when sintered, contain small amount of Mg $B_4$ and MgAg impurity phases. From the magnetization study, it was found that the flux pinning was improved in the high magnetic field region (> 3 T) only when 10w/o Ag was added to Mg $B_2$. The "two step" structures in ZFC M(T) curve gradually increased as the amount of Ag added increased. Pinning centers can be created by adding a suitable amount of Ag nano-powder which is not too large to increase the decoupling between the Mg $B_2$ grains.crease the decoupling between the Mg $B_2$ grains.

• 미생물학회지
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• 제35권3호
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• pp.173-179
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• 1999

Rhizoctonia solani 분류를 위해 균사의 anastomosis group과 grouprks의 유전적 차이의 분석을 위해 rDNA 의 PCR-RFLP 와 RFLP를 실시하였다. rDNA 의 PCR-RFLP 결과 R. solani 는 크게 5 group 으로 나뉘어졌다. 균주 번호 1번과 3번은 AG-5 그룹과 0.976의 높은 상동성을 보였고, 12번, 13번은 AG-2-2와 0.976의 상동성을 보였다. 균주번호 7,8,11,13,15 는 AG-1에 속하였다. 제한효소 HaeIII로 절단하였을 때 균주번호 4,5,7,8은 700 bp에서 하나의 밴드가 나타나 AG-1에 속하였고, 균주번호 9는 AG-2-1과 517 bp에서 하나의 밴드가 나타났다. 도한 제한효소 Msp I을 사용하여 southern blotting을 한 결과 더 다양한 절단양상을 보이며 AG 간의 차이가 나타났다. AG-2-1과 균주번호 9는 200 bp에서 하나의 밴드가 나타났다. 균주 3,4,5,10,11,13은 AG-1과 1kb에서 하나의 밴드로 나타났다.

• 한국결정성장학회지
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• 제16권5호
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• pp.189-197
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• 2006

[$AgGaSe_2$] 단결정 박막을 수평 전기로에서 합성한 $AgGaSe_2$ 다결정을 증발원으로하여, hot wall epitaxy(HWE) 방법으로 증발원과 기판(반절연성-GaAs(100))의 온도를 각각 $630^{\circ}C,\;420^{\circ}C$로 고정하여 성장하였다. 이때 단결정 박막의 결정성은 광발광 스펙트럼과 이중결정 X-선 요동곡선(DCRC)으로 부터 구하였다. $AgGaSe_2$의 광흡수 스펙트럼으로부터 구한 온도에 의존하는 에너지 밴드갭 $E_g(T)$는 Varshni 공식에 fitting한 결과 $E_g(T)=1.9501eV-(8.79x10^{-4}eV/K)T^2(T+250K)$를 잘 만족하였다. 성장된 $AgGaSe_2$ 단결정 박막을 Ag, Ga, Se 분위기에서 각각 열처리하여 10K에서 photoluminescience(PL) spectrum을 측정하여 점 결함의 기원을 알아보았다. PL 측정으로 부터 얻어진 $V_{Ag},\;V_{Se},\;Ag_{int}$, 그리고 $Se_{int}$는 주개와 받개로 분류되어졌다. $AgGaSe_2$ 단결정 박막을 Ag 분위기에서 열처리하면 p형으로 변환됨을 알 수 있었다. 또한, Ga 분위기에서 열처리하면 열처리 이전의 PL 스펙트럼을 보이고 있어서, $AgGaSe_2$ 단결정 박막에서 Ga은 안정된 결합의 형태로 있기 때문에 자연 결함의 형성에는 관련이 없음을 알았다.

• 대한핵의학회지
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• 제15권1호
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• pp.27-32
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• 1981

HBsAg. was identified in the urine of the patients positive for serum HBsAg. by Tripatzis in 1970. In 1977, Hourani et al reported the incidence of HBsAg. in urine was about 52% in the patients positive for serum HBsAg. with hemodialysis treatment due to chronic renal failure. A series of studies on the HBsAg. in urine has revealed the urine of the patients positive for serum HBsAg. to be important source of infection. But there's much room to debate on the relationship of HBsAg. in urine with infectivity and the exact mechanism of urinary emergence of HBsAg. The authors detected HBsAg. in serum and urine by employing sandwitch solid-phase rad ioimmunoassay, and performed urinalysis, liver function test and renal function evaluation. Percutanous liver and/or kidney biopsis were done. Among 38 renal disease patients, 9 cases (23.4%) were shown to be positive for serum HBsAg. and 5 cases (55.5%) among above 9 patients positive for urine HBsAg.. 56 cases (67.4%) of 83 liver disease patients revealed positive for serum HBsAg. but only 11 cases (13.2%) among the 56 cases positive fo urine HBsAg. All 10 renal and liver disease patients revealed positive serum HBsAg., and among the 9 cases (90%) positive for urine HBsAg.. In the 25 patients positive for urine HBsAg. all of 5 renal patients and 9 renal and liver patients had hematuria or/and proteinuria above 2 positive for albumin. But in the 11 liver patients 6 cases (55.1%) were normal findings. And there's no significant difference in cpm of urine HBsAg. between the patient positive for serum HBsAg. and negative, and in cpm of serum HBsAg. between liver and renal disease patients. But there's statistical significance in cm of urine HBsAg. between renal and liver diseases.

• 한국분말재료학회지
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• 제18권4호
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• pp.372-377
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• 2011

In this study, we reported the microstructure and properties of Ag-$SnO_2$ contact materials fabricated by a controlled milling process with subsequent consolidation. The milled powders were consolidated to bulk samples using a magnetic pulsed compaction process. The nano-scale $SnO_2$ phases were distributed homogeneously in the Ag matrix after the consolidation. The relative density and hardness of the Ag-$SnO_2$ contact materials were 95~96% and 89~131 Hv, respectively.

• 한국재료학회지
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• 제30권6호
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• pp.285-291
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• 2020

Recent advances in technology using ultra-thin noble metal film in oxide/metal/oxide structures have attracted attention because this material is a promising alternative to meet the needs of transparent conduction electrodes (TCE). AZO/Ag/AZO multilayer films are prepared by magnetron sputtering for Cu₂ZnSn(S,Se)₄ (CZTSSe) of kesterite solar cells. It is shown that the electrical and optical properties of the AZO/Ag/AZO multilayer films can be improved by the very low resistivity and surface plasmon effects due to the deposition of different thicknesses of Ag layer between oxide layers fixed at AZO 30 nm. The AZO/Ag/AZO multilayer films of Ag 15 nm show high mobility of 26.4 ㎠/Vs and low resistivity and sheet resistance of 3.58^⁎10^-5 Ωcm and 5.0 Ω/sq. Also, the AZO/Ag (15 nm)/AZO multilayer film shows relatively high transmittance of more than 65 % in the visible region. Through this, we fabricated CZTSSe thin film solar cells with 7.51 % efficiency by improving the short-circuit current density and fill factor to 27.7 mV/㎠ and 62 %, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.79-80
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• 2007

To obtain the single crystal thin films, $AgGaSe_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $630^{\circ}C\;and\;420^{\circ}C$, respectively. The temperature dependence of the energy band gap of the $AgGaSe_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g$(T) = 1.9501 eV - ($8.79{\times}10^{-4}$ eV/K)$T^2$/(T + 250 K). After the as-grown $AgGaSe_2$ single crystal thin films was annealed in Ag-, Se-, and Ga-atmospheres, the origin of point defects of $AgGaSe_2$ single crystal thin films has been investigated by the photoluminescence(PL) at 10 K. The native defects of $V_{Ag},\;V_{Se},\;Ag_{int},\;and\;Se_{int}$ obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Ag-atmosphere converted $AgGaSe_2$ single crystal thin films to an optical p-type. Also, we confirmed that Ga in $AgGaSe_2$/GaAs did not form the native defects because Ga in $AgGaSe_2$ single crystal thin films existed in the form of stable bonds.

• 한국재료학회지
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• 제24권11호
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• pp.617-624
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• 2014

To elucidate the effects of a pretreatment process on the uniformity of Ag electroless plating on Cu flakes, pretreatment time was mainly considered with a mixed solution of 0.15 M ammonium hydroxide and 0.0375 M ammonium sulphate. Optical inspection of Ag-coated Cu flakes determined that the optimal pretreatment time is 120 s. Repetition of the sequence in which Ag plating was done immediately after the pretreatment of 120 s clearly enhanced the plating uniformity. Scanning electron microscopy revealed that holes were formed irregularly on some Cu flakes during the period from the asdropping of an Ag precursor solution to 5 min. The hole formation was judged to be due to continuous removal of Cu on the local surfaces by the repetitive formation and elimination of $Cu_2O$ or $Cu(OH)_2$ layers. However, the increase of the amount of Ag coating suppressed the hole creation and increasingly enhanced the antioxidant property.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.98-99
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• 2008

To obtain the single crystal thin films, $AgGaSe_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $420^{\circ}C$, respectively. The temperature dependence of the energy band gap of the $AgGaSe_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g$(T) 1.9501 eV - ($8.79\times10^{-4}$ eV/K)$T^2$/(T + 250 K). After the as-grown $AgGaSe_2$ single crystal thin films was annealed in Ag-, Se-, and Ga-atmospheres, the origin of point defects of $AgGaSe_2$ single crystal thin films has been investigated by the photoluminescence(PL) at 10K. The native defects of $V_{Ag}$, $V_{Se}$, $Ag_{int}$, and $Se_{int}$ obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Ag-atmosphere converted $AgGaSe_2$ single crystal thin films to an optical p-type. Also, we confirmed that Ga in $AgGaSe_2$/GaAs did not form the native defects because Ga in $AgGaSe_2$ single crystal thin films existed in the form of stable bonds.