• 제목/요약/키워드: NaD1

검색결과 2,045건 처리시간 0.028초

AOX 감소를 위한 새로운 표백법 (제1보) - A처리 및 $D_{(H/L)}$ 처리를 이용한 표백법 - (Studies on the Pulp Bleaching for Reducing AOX(I) - The Pulp Bleaching Method Using A and $D_{(H/L)}$ Treatment -)

  • 윤병호;김기선;이선호
    • 펄프종이기술
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    • 제29권1호
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    • pp.52-61
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    • 1997
  • This study was aimed to decrease AOX(Adsorbed Organic Halide Compounds) by applying bleaching methods of A(HNO$_3$ + NaNO$_2$) and $D^{(H/L)}$(dual pH chlorine dioxide bleaching) to conventional OCEDED bleaching stages. And so we investigate the effects of NSA treatment and the influence of production rate of ion species in chlorine dioxide and pulp mixtures according to various pH as well as dual pH on pulp bleaching. Finally the effects of AOC_DED^{(H/L)}ED^{(H/L)}$ bleaching stage were investigated by measuring AOX, brightness, kappa number and viscosity of pulps. A stage was treated by using 4% $HNO_3$ and 0.05~2.0% $NaNO_2$ on pulp and $D^{(H/L)}$ stage was like that pulp mixed with chlorine dioxide solution was adjusted at pH 7.0 and reacted in pulp cosistency 3%, S~20min, $70^{\circ}C$, and then successively for 160~175min at pH 4.0. It was found that suitable $NaNO_2$ addition rate was at 0.6% where the brigtness of pulp was most higher and pulp viscosity was not decreased much. Chlorate ($CIO_3$) was decreased according to pH increase but chlorite($CIO_2$) was highly decreased according to pH increase. And chloride was slightly increased with pH increase. The applying of A and D^{(H/L)}$ bleaching stages to some various multiple bleaching stages ($AOC_DED^{(H/L)}/EopD^{(H/L)} etc.$) had good results that brightness was increased more 2~3% ISO than conventional method(OCEDEopD), but viscosity was dropped by only 1~2cps.

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KOSPI 상장기업의 업종별 BSC 도입효과 분석 : 주요재무 비율 및 투자규모 중심으로 (Analysis of BSC Adoption Effect by KOSPI listed Companies : Focus on Major Financial Ratios and Investment Scale)

  • 김주은
    • 경영과학
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    • 제34권3호
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    • pp.15-41
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    • 2017
  • The purpose of this study is to analyze the effects of the BSCs of 642 firms excluding the financial and insurance companies listed on KOSPI. The analysis of financial performance through analysis of major financial ratios between BSC and non-BSC firms is compared with the input of human and material resources for business growth. We will promote the spread of BSC and examine the areas differentiated performance improvement. The analytical categories are manufacturing, service, wholesale and retail, and information and communications, which are 2,136 business years out of 2,378 final analytical samples. The results of the analysis are as follows. As a result of the analysis, among the four industries analyzed, the industries that showed the best performance were manufacturing. In the case of service industry, growth and activity were lower than those of non-adoption (NA) companies, but the operating margin was significantly different from manufacturing. However, market value was higher than that of NA companies, and R&D expenditures and advertising expenses were significantly higher than NA firms. On the other hand, there was no significant difference in profitability between the BSC and NA firms, but the market value was very significant. EPS is 5.22 times, BPS is 5.64 times, PBR is 1.3 times, and EVA is 35 times higher. In addition, R&D expenditure and advertising expenditure are more than twice as high as those of NA. In the case of the service industry, there is no significant difference in the growth performance from the NA firms. Activity indicators, BSC introduced companies are three times lower than both the total assets turnover and the capital turnover rate. The operating profit margin was high at 45.8% for introduced companies and 37.2% for non-introduced companies. In market value analysis, only BPS was 1.68 times higher. On the other hand, investment in welfare expenses is 0.2% of total assets, which is relatively low compared to NA firms. However, research and development expenses and advertising expenses are 2.1% and 1.02% of total assets, respectively, but they are relatively lower than those of NA firms. Unlike the manufacturing and service industries, wholesale and retail trade was significantly higher than the NA firms in terms of sales growth and total assets growth rate. In terms of market value, EPS and BPS were significantly higher, but the benefits, R&D expenditures, and advertising expenses were lower than those of NA firms. The information and communication industry showed lower level of performance than the NA firms in all indicators except cash liquidity, BPS, and EVA.

Investigation of Al-Ni Alloys Deposition during Over-discharge Reaction of Na-NiCl2 Battery

  • Kim, Jeongsoo;Jo, Seung Hwan;Park, Dae-In;Bhavaraju, Sai;Kang, Sang Ook
    • 전기화학회지
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    • 제19권3호
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    • pp.57-62
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    • 2016
  • The over-discharging phenomena in sodium-nickel chloride batteries were investigated in relation to decomposition of molten salt electrolyte and consequent metal co-deposition. From XRD analysis, the material deposited on graphite cathode current collector was revealed to be by-product of molten salt electrolyte decomposition. In particular, the result showed that the Ni-Al alloys ($Al_3Ni_2$, $Ni_3Al$ and $Al_3Ni$) were electrochemically deposited on graphite current collectors in line with over-discharging behaviors. It is assumed that the $NiCl_2$ solubility in molten salt electrolytes leads to the co-deposition of Ni-Al alloys by increasing metal deposition potential above 1.6 V (vs. $Na/Na^+$). The cell tests have revealed that the composition of molten salt electrolytes modified by various additives makes a decisive influence on the over-discharging behaviors of the cells. It was revealed that NaOCN addition to molten salt electrolytes was advantageous to suppress over-discharge reactions by modifying the characteristics of molten salt electrolytes. NaOCN addition into molten salt electrolytes seems to suppress Ni solubility by maintaining basic melts. The cell using modified molten salt electrolyte with NaOCN (Cell D) showed relatively less cell degradation compared with other cells for long cycles.

루비듐 증기로 처리한 탈수한 제올라이트 X의 결정학적 연구 (Crystallographic Studies of Dehydrated Zeolite-X Reacting with Rubidium Vapor)

  • 한영욱
    • 한국광물학회지
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    • 제6권2호
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    • pp.116-121
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    • 1993
  • 제올라이트 $Na_{78}Rb_{28}-X$ 단결정을 $Na_{92}-X(Na_{92}Si_{100}Al_{92}O_{384})$$350^{\circ}C$에서 0.1Torr의 Rb 증기로 처리하여 만들어서 그 구조를 X-선 단결정법으로 공간군 Fd3로서 결정하였다 (${\alpha}=25.045(4){\AA}$). 구조는 I>$3{\sigma}(I)$인 회절반점 353개를 사용하여 최종오차지수 $R_1=0.082$, $R_2=0.084$까지 정밀화하였다. 단위포당 92개의 $Na^+$ 이온 중 대략 28개의 $Na^+$ 이온이 환원되고, 환원되어 생성된 28개의 Na' 중 약 14개만 제올라이트 골조내에 잔류하고 있다. 소다라이트 동공내에 사면체의 대칭성 ($T_d$)을 가지고 결합각 $109.5^{\circ}$, 결합거리 $2.80(2){\AA}$를 갖는다. $Na_5{^{4+}}$ 클라스트를 이루는 4개의 말단 원자와 골조 산소원자 사이의 결합거리는 $2.80(2){\AA}$이다. 몇몇 이중 6-링의 중심에 $Na_5{^{4+}}$ 클라스트 두 개를 선형으로 연결하여 지그재그형의 덩어리로 만드는 $Na^0$원자가 있다. 소다라이트 동공 중심과 이중 6-링에 있는 $Na^0$원자의 비편재화된 전자가 $Na_5{^{4+}}$ 클라스트를 안정화시키고 있다.

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Mathematical Model for Predicting the Growth Probability of Staphylococcus aureus in Combinations of NaCl and NaNO2 under Aerobic or Evacuated Storage Conditions

  • Lee, Jeeyeon;Gwak, Eunji;Ha, Jimyeong;Kim, Sejeong;Lee, Soomin;Lee, Heeyoung;Oh, Mi-Hwa;Park, Beom-Young;Oh, Nam Su;Choi, Kyoung-Hee;Yoon, Yohan
    • 한국축산식품학회지
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    • 제36권6호
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    • pp.752-759
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    • 2016
  • The objective of this study was to describe the growth patterns of Staphylococcus aureus in combinations of NaCl and $NaNO_2$, using a probabilistic model. A mixture of S. aureus strains (NCCP10826, ATCC13565, ATCC14458, ATCC23235, and ATCC27664) was inoculated into nutrient broth plus NaCl (0, 0.25, 0.5, 0.75, 1, 1.25, 1.5, and 1.75%) and $NaNO_2$ (0, 15, 30, 45, 60, 75, 90, 105, and 120 ppm). The samples were then incubated at 4, 7, 10, 12 and $15^{\circ}C$ for up to 60 d under aerobic or vacuum conditions. Growth responses [growth (1) or no growth (0)] were then determined every 24 h by turbidity, and analyzed to select significant parameters (p<0.05) by a stepwise selection method, resulting in a probabilistic model. The developed models were then validated with observed growth responses. S. aureus growth was observed only under aerobic storage at $10-15^{\circ}C$. At $10-15^{\circ}C$, NaCl and $NaNO_2$ did not inhibit S. aureus growth at less than 1.25% NaCl. Concentration dependency was observed for NaCl at more than 1.25%, but not for $NaNO_2$. The concordance percentage between observed and predicted growth data was approximately 93.86%. This result indicates that S. aureus growth can be inhibited in vacuum packaging and even aerobic storage below $10^{\circ}C$. Furthermore, $NaNO_2$ does not effectively inhibit S. aureus growth.

Effects of ${\alpha}_1-Adrenergic$ Receptor Stimulation on Intracellular $Na^+$ Activity and Twitch Force in Guinea-Pig Ventricular Muscles

  • Chae, Soo-Wan;Gong, Q.Y.;Wang, D.Y.;Lee, Chin-O.
    • The Korean Journal of Physiology
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    • 제29권2호
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    • pp.203-216
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    • 1995
  • The effects of ${\alpha}_1-adrenergic$ receptor stimulation on membrane potential, intracellular $Na^+$ activity, and twitch force were investigated in ventricular muscles from guinea-pig hearts. Action potentials, intracellular $Na^+$ activity, and twitch force of ventricular papillary muscles were measured simultaneously under various experimental conditions. Stimulation of the ${\alpha}_1-adrenergic$ receptor by phenylephrine produced variable changes in action potential duration, a slight hyperpolarization of the diastolic membrane potential, a decrease in intracellular $Na^+$ activity, and a biphasic inotropic response in which a transient negative inotropic response was followed by a sustained positive inotropic response. These changes were blocked by prazosin, an antagonist of the ${\alpha}_1-adrenergic$ receptor, but not by atenolol, an antagonist of the ${\beta}-adrenergic$ receptor. This indicates that the changes in membrane potential, intracellular $Na^+$ activity, and twitch force are mediated by stimulation of the ${\alpha}_1-adrenergic$ receptor, but not by stimulation of ${\beta}-adrenergic$ receptor. The decrease in intracellular $Na^+$ activity was not observed in quiescent muscles, depending on the rate of the action pontentials in beating muscles. The intracellular $Na^+$ activity decrease was substantially inhibited by tetrodotoxin. However, the decrease in intracellular $Na^+$ activity was not affected by an inhibition of the $Na^+-K^+$ pump. Therefore, the decrease in intracellular $Na^+$ activity mediated by the ${\alpha}_1-adrenergic$ receptor appears to be due to a reduction of $Na^+$ influx during the action potential, perhaps through tetrodotoxin sensitive $Na^+$ channels. Our study also revealed that the decrease in intracellular $Na^+$ activity might be related to the transient negative inotropic response. The intracellular $Na^+$ activity decrease could lower intracellular $Ca^{2+}$ through the $Na^+-Ca^{2+}$ exchanger and thereby produce a decline in twitch force.

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Effects of Salts on the Conformation and Catalytic Properties of D-Amino Acid Aminotransferase

  • Ro, Hyeon-Su
    • BMB Reports
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    • 제35권3호
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    • pp.306-312
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    • 2002
  • The effects of salts on the biochemical properties of D-amino acid aminotransferase from Bacillus sp. YM-1 have been studied to elucidate both the inhibitory effects of salts on the activity and the protective effects of salts on the substrate-induced inactivation. The results from UV-visible spectroscopy studies on the reaction of the enzyme with D-serine revealed that salt significantly reduced the rate of the formation of the quinonoid intermediate and its accumulation. The kinetic and spectroscopy studies of the reaction with $\alpha$-[$^2H$]-DL-serine in different concentrations of NaCl provided evidence that the rate-limiting step was changed from the deprotonation of the external aldimine to another step(s), presumably to the hydrolysis of the ketimine. Gel filtration chromatography data in the presence of NaCl showed that the enzyme volume was reduced sharply with the increasing NaCl concentration, up to 100 mM. An additional increase of the NaCl concentration did not affect the elution volume, which suggests that the enzyme has a limited number of salt-binding groups. These results provide detailed mechanistic evidence for the way salts inhibit the catalytic activity of D-amino acid aminotransferase.

산표면처리 후 노출된 상아질 교원섬유의 용해가 하이브리드층 형성에 미치는 영향 (EFFECT OF COLLAGEN DISSOLUTION IN ACID CONDITIONED DENTIN ON RESIN-DENTIN HYBRID LAYER)

  • 전성민;손호현;이광원
    • Restorative Dentistry and Endodontics
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    • 제21권1호
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    • pp.227-241
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    • 1996
  • The effect of collagen dissolution in acid conditioned dentin was morphologically examined by both scanning and transmission electron microscopy. 18 freshly extracted human molars and dentin bonding systems of All Bond 2, Scotchbond Multipurpose, Superbond D-Liner were used in this study. For SEM preparation, each 3 of ~ exposed dentin surfaces were acid conditioned by using various acids within the above three bonding systems respectively. After acid conditioning of the other 3 exposed dentin surfaces as above, they were treated with 1.7% NaOCl for 2 minutes. The remaining 3 dentin surfaces were acid conditioned and treated with 3.3 % NaOCl for 2 minutes. All of the specimens were then fixed in 4 % glutaraldehyde for 12 h at $4^{\circ}C$ and dehydrated in ethanols grades from 50 % to 100 %, then surface changes of the specimens were observed by using SEM. For TEM preparation, exposed dentin surfaces were acid conditioned with the same acid as SEM specimens and treated with 1.7%, 3.3 % NaOCl respectively, then applied with corresponding bonding agents. After the procedures were finished, composite resin were applied on the dentin surfaces and light cured. Small, rectangular sticks with end dimensions of approximately 1 by 1 mm were sectioned and further sample preparative techniques for transmission electron microscopy were performed in accordance with the procedures used for ultrastructural TEM observations of calcified tissues. The results were as follows : 1. In the 1.7 % NaOCl retreated specimens after acid conditioning, the porous dentin surface of intertubular dentin and wide opening of dentinal tubules were appeared. And there were fine irregularities on the intertubular dentin, indicating a clear difference as compared with the acid conditioned specimens. 2. In the 3.3% NaOCl retreated specimens after acid conditioning, the intertubular dentin was further eroded causing a more porous and wider opening of dentinal tubules. Moreover, sharp irregularities on the intertubular dentin were more evident than those of acid conditioned and 1.7% NaOCl retreated specimens. 3. In all of the acid conditioned specimens, the resin-dentin hybrid layer of approximately 3.5mm thickness was formed and the collapsed collagen layer was observed on the uppermost part of hybrid layer in the specimens applied with All Bond 2. The collgen fibrils of intertubular dentin in specimens applied with Scotchbond Multipurpose were running perpendicular to the interface, and electron dense black layer demarcated from the deep unaltered dentin was more evident in the specimen applied with Superbond D-Liner than any other specimens. 4. In the 1.7 % NaOCl retreated specimens after acid conditioning, the resin-dentin hybrid layer of approximately 2.5-3.0mm thickness was formed and the collapsed collagen layer and longitudinally running collagen fibrils as shown in the acid conditioned specimens were observed in the specimens applied with All Bond 2 and Superbond D-Liner. 5. In all of the 3.3% NaOCl retreated specimens after acid conditioning, the evidence of resin-dentin hybrid layer was not identified ; nevertheless, the longitudinally running collagen fibrils remained slightly in the specimens applied with All Bond 2.

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$Ag^+-Na^+$이온교환법을 이용한 $1.31/1.55\mu\textrm{m}$ 두파장 방향성 광 결합기의 모델링 및 제작 (Modeling and fabrication of $1.31/1.55\mu\textrm{m}$ coarse WDM optical directional coupler using $Ag^+-Na^+$ ion-exchanged glass)

  • 강동성
    • 한국광학회지
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    • 제11권5호
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    • pp.335-339
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    • 2000
  • 본 논문에서는 2" BK7 유리 기판에 $Ag^+-Na^+$ 이온교환법을 이용한 $1.31/1.55\mu\textrm{m}$ 두파장 방향성 광 결합기를 제작하였다. 제작 및 모델링 조건으로는 이온교환 온도 $340^{\circ}C$, 이온교환 시간 12h, 확산이온농도 0.67[MF]-NaNO3+0.33[MF]-KNO3+1$\times$-3[MF]-AgNO3, 이었으며 굴절율의 분포는 폭 방향으로는 가우시안 함수로, 깊이 방향으로는 에러 함수 분포로 근사화 하였다. 광 결합기를 구성하는 채널 도파로의 폭은 단일 모드 조건으로부터 $4\mu\textrm{m}$이었고 간격은 $8\mu\textrm{m}$이었다. 제작된 소자의 전체 길이는 16mm이었으며 광 결합길이는 12.6mm이었고 $1.31/1.55\mu\textrm{m}$ 두파장에서 각각 18dB이상의 소멸비를 나타내었다.

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