• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.37-37
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• 2017

Mechanistic studies of halophytes are urgent areas of agricultural research due to the increase in saline-contaminated and irrigated land worldwide. The halophyte Suaeda glauca (S. glauca) has advantages in terms of biomass and saline elimination due to its large mass and well-developed phenotype on seashores, although its mechanistic features and growing specificities still require systematic investigation. In this study, S. glauca was cultivated under various saline concentrations (0-400 mM) in Hoagland's solution in the absence or presence of indole derivatives to elucidate physiological features. The results confirmed the optimal growth and development of S. glauca in 50 mM NaCl, and morphologies such as the number of branches, shoot length, and fresh and dry weights were improved by indole-3-carboxylic acid (ICA) treatment. The cation concentrations in roots, shoots and leaves were investigated to examine the ionic imbalances in response to saline treatment, and the results demonstrated that sodium ions accumulated to high concentrations in leaves. The levels of calcium and potassium ions in roots were maintained or slightly decreased in the presence of 50 mM NaCl and proline concentration was increased significantly in roots at optimal concentrations. These results demonstrate that the concentrations of ions and metabolites are key regulators of optimal growth by regulating the physiology of halophytes.

• 공업화학
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• 제5권3호
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• pp.443-450
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• 1994

Polyacrylic acid를 NaOH와 $NH_4OH$로 중화시켜 중화도가 다른 polyelectrolyte를 만든 후, 수용액 상에서 ethylene glycol diglycidyl ether(EGDE)로 가교시켜 안정한 상태의 젤을 얻었다. 안정한 젤이 얻어지는 가장 작은 polyelectrolyte의 농도인 $C_{gel}$은 polyelectrolyte의 extended from에도 불구하고 비슷한 분자량의 중성 고분자의 간과 비슷하였다. 전해질 고분자에 대한 scaling이론에 의하면 semi-dilute영역에서의 전해질 고분자용액은 분자량 의존성이 없어야 함에도 불구하고 gelation결과는 중성 고분자와 흡사한 분자량 의존성을 보이며 entanglement 농도인 $C^{**}$와 비교했을 때에도 $C_{gel}$은 훨씬 큰 값을 갖는다. 이는 고분자 전해질의 농도가 진해질수록 용액의 이온세기가 증가하여 extended from에서 coil form으로 변화되기 때문으로 보인다. 고분자 전해질의 중화도에 따른 gelation은 100% 중화된 시료의 $C_{gel}$값과 분자량 의존성에 있어 거의 비슷한 경향을 보이며 이는 고분자 전해질의 conformation변화가 이온세기에 상당히 민감함을 보여 준다. 고분자 전해질 수용액에 추가로 저분자량의 염을 가하면 고분자의 용액 속에서의 크기가 더욱 축소하여 더 큰 $C_{gel}$값을 보인다.

• 한국전기전자재료학회논문지
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• 제29권10호
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• pp.652-658
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• 2016

Thermal batteries use inorganic salt as electrolyte, which is inactive at room temperature. As soon as heat pellets are fired by an igniter, all the solid electrolytes are instantly melted into excellent ionic conductors. However, the abnormal heat generation by the igniter flame or heat pellets causes the thermal decomposition of the electrode and the melting of the anode, eventually leading to a thermal runaway, which results in overheating or explosion. The thermal runaway can be significantly reduced by the adoption of $Zr/BaCrO_4$ heat papers. In this study, the heat papers with various ratios of fuel (Zr) and oxidizer ($BaCrO_4$) were prepared by the paper-making process. We have investigated the calorimetric value, burning rate, and ignition sensitivity. The ignition test of heat pellets and the discharge test of thermal batteries were also carried out. At the composition of 40 wt.% of Zr, the heat papers showed the highest specific calorimetric value and burning rate. As a result, $Zr/BaCrO_4$ heat paper made by the paper-making process has shown the applicability for thermal batteries.

• Asian Journal of Atmospheric Environment
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• 제7권4호
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• pp.217-226
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• 2013

The collection of TSP and $PM_{2.5}$ aerosols has been made at the Gosan Site of Jeju Island during 2008-2011, and their ionic and elemental species were analyzed, in order to examine the seasonal variation and characteristics of aerosol compositions. The anthropogenic components ($NH_4{^+}$, $nss-SO_4{^{2-}}$, $NO_3{^-}$, S, Zn, Pb) and the soil components ($nss-Ca^{2+}$, Al, Fe, Ca) showed high concentrations in spring as the prevailing westerly wind, but the concentrations of the sea-salt components ($Na^+$, $Cl^-$) were high in winter. In TSP, the neutralization by $NH_3$ increased in summer, but the neutralization by $CaCO_3$ increased in spring and fall seasons. The organic acids ($HCOO^-$, $CH_3COO^-$) contributed to the acidification of the aerosols by only 5.0%, so the acidification could be mostly contributed by the inorganic acids ($SO_4{^{2-}}$, $NO_3{^-}$). From the examination of the source origins by factor analysis, the compositions of TSP were influenced by the order of soil > anthropogenic > marine, on the other hand, those of $PM_{2.5}$ were by the order of anthropogenic > marine > soil. The backward trajectory analyses showed that the concentrations of $NH_4{^+}$, $nss-SO_4{^{2-}}$, $NO_3{^-}$ and $nss-Ca^{2+}$ increased highly when the air masses had moved from China continent into Gosan area of Jeju Island.

• 한국염색가공학회지
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• 제13권2호
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• pp.28-28
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• 2001

Four kinds of neutral sodium salts with different anions, NaF, NaCl, NaBr, and NaI, were added to the dye bath to accurately understand the effect of anions on the reactive dyeing of silk with C. I. Reactive Black 5. The sodium cation lowered the negative surface potential of the silk and increased the dye-uptake on fille fabric as reported previously. However, because of the discrepancy in the anions′inhibition power from cation′s lowering the surface negative potential the amount of the dye on the silk fiber was different from each other in the order of $F^-\;>\;Cl^-\;>\; Br^-\;>\;I^-$. The activation energy($E_a$) for the dyeing was in the order of $F^-\;>\;Cl^-\;>\; Br^-\;>\;I^-$ but the dye-uptake on the fabric and the activation free energy(Δ$G^*$), the real energy barrier for the reaction, were in the order of $F^-\;>\;Cl^-\;>\; Br^-\;>\;I^-$ because the strength of the interaction of the anions with sodium cations was the same as the order of the latter. In other words $F^-$ exerted the weakest electrostatic force on $Na^+$and competed with the dyestuff anions least of all. The decrease in Δ$S^*$may be due to the looesly bonded activated complex of dyestuff anions, sodium cations and fiber molecules at transition state. It was clarified from the Bronsted equation that sodium salts with different anions also had fille ionic strength effect and the specific salt effect on the reactive dyeing.

• 공업화학
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• 제7권3호
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• pp.433-442
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• 1996

분자량이 큰 Poly(ethylene oxide)[PEO] 고분자에 $LiClO_4$, $LiCF_3SO_3$ 등의 리튬염과 ethylene carbonate(EC), propylene carbonate(PC) 등의 가소제를 고정화시킨 고분자 전해질의 전기화학적 특성 및 물리적 성질을 조사하였다. 가소제가 첨가된 PEO-Li계 고분자 전해질은 상온에서 $10^{-4}S/cm$의 이온 전도도를 보였고 4.5 V(vs. $Li^+/Li$)까지 높은 전기화학적인 안정성을 나타냄으로써 리튬 2차전지에 적용 가능한 것으로 나타났다. 리튬염 및 가소제의 첨가에 따라 PEO의 결정상이 감소되었고 특히 $LiClO_4$, PC등이 $LiCF_3SO_3$, EC 등에 비하여 더 효과적인 것으로 나타났다. 리튬염의 농도가 증가할수록 고분자 전해질의 유리전이온도($T_g$)는 증가되었으며 반면에 융점온도($T_m$)는 감소하는 것으로 나타났다. 가소제가 첨가된 고분자 전해질은 $6^{\circ}C$에서 결정화 되었다.

• 대한화장품학회지
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• 제37권3호
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• pp.283-288
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• 2011

미네랄은 이온 상태로 존재하기 때문에, 카보머나 아크릴레이트 계 점증 시스템의 저점도 가용화 제형에서는 고농도로 안정화하기 어렵다. 본 연구에서는 젤 에센스 제형 내 고농도의 미네랄을 안정화하기 위하여, 염류에 안정한 실리콘 코폴리올을 이용한 네트워크 필름을 만들고, 네트워크 내에 미네랄을 고농도로 포집하여 피부에 오랜 시간 동안 고농도의 미네랄이 천천히 피부에 흡수될 수 있도록 제형을 설계하였다. 설계한 최적의 제형을 시료로 이용하여 6주간의 임상실험을 진행하였으며, 그 결과 피부 각질층의 미네랄 함량이 증가하고, 아미노산이 증가함으로써 각질층의 수분량이 증가하여 피부 투명도가 증가하였고 묵은 각질이 탈락하고 각질층이 정돈되어 피부 칙칙함과 피부 밝기가 개선됨을 확인하였다.

• 대한화학회지
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• 제44권6호
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• pp.592-599
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• 2000

여러 가지 온도, 조성 및 농도에서 이성분계 세라믹 복합체 TPSZ(titania partially-stabilized zirconia)의 미분말을 초음파분무열분해법에 의하여 합성하였으며, 합성공정인자가 분체특성에 미치는 영향을 검토하고, 합성된 분체의 특성을 조사하였다. 출발용액의 제조는 금속염의 농도가 0.025~0.1 M이 되도록 증류수에 용해하고, 그 조성비는 $ZrO_2$ 90~97.5 wt%에 $TiO_2$ 2.5~10 wt%가 되도록 하였다. 합성시 열분해 영역에서의 온도는 건조부가 400~550$^{\circ}C$, 반응부는 800~1100$^{\circ}C$로 하였으며, 합성된 분체는 습식으로 포집하여 110$^{\circ}C$에서 3시간 동안 건조하였다. 합성된 미분체의 특성을 Raman Spectroscopy, X-ray diffraction(XRD), Scanning Electron Microscopy(SEM), Transmission Electron Microscopy (TEM) 및 Particle Size Analyzer(PSA)로써 조사하였고, Inductively Coupled Plasma-Atomic Emission Spectroscopy(ICP-AES)로써 순도 및 조성을 분석하였다.

• International Journal of Concrete Structures and Materials
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• 제11권2호
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• pp.199-213
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• 2017

Chloride penetration is among the main causes of corrosion initiation in reinforced concrete (RC) structures producing premature degradations. Weather and exposure conditions directly affect chloride ingress mechanisms and therefore the operational service life and safety of RC structures. Consequently, comprehensive chloride ingress models are useful tools to estimate corrosion initiation risks and minimize maintenance costs for RC structures placed under chloride-contaminated environments. This paper first presents a coupled thermo-hydro-chemical model for predicting chloride penetration into concrete that accounts for realistic weather conditions. This complete numerical model takes into account multiple factors affecting chloride ingress such as diffusion, convection, chloride binding, ionic interaction, and concrete aging. Since the complete model could be computationally expensive for long-term assessment, this study also proposes model simplifications in order to reduce the computational cost. Long-term chloride assessments of complete and reduced models are compared for three locations in France (Brest, Strasbourg and Nice) characterized by different weather and exposure conditions (tidal zone, de-icing salts and salt spray). The comparative study indicates that the reduced model is computationally efficient and accurate for long-term chloride ingress modeling in comparison to the complete one. Given that long-term assessment requires larger climate databases, this research also studies how climate models may affect chloride ingress assessment. The results indicate that the selection of climate models as well as the considered training periods introduce significant errors for mid- and long- term chloride ingress assessment.

• 대한화학회지
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• 제33권1호
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• pp.11-17
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• 1989

피라지니움염인 피라지니움 크로로크로메이트와 디피라지니움 트리크로로메이트는 HCl용액과 $CH_2Cl_2$용액에 피라진을 각각 녹이고 거기에 CrO$_3$ 를 가하므로 얻었다. 이들 화합물은 모두 비흡수성이나 물에 잘 녹었다. 이들 화합물의 물리적 특성으로 용해도, pH, 전기전도도, 용융점 등을 측정하였다. 이들 화합물은 전기 전도도 측정으로 $C_4H_4N_2H^+$, $CrO_3Cl^-$, $Cr_3O^{2-}_{10}$ 이온 등으로 용액 내에 존재하는 것을 알 수 있었다. 또한 DTA에 의해 염의 첫번째 분해시에 CrO$_3$ 가 분리되고 두번째 분해시에는 $Cr_2O_3$로 변해지고 이때 무게가 감소됨을 알 수 있었다. 특히 동일한 조건하에서 디피라지니움 염은 피리딘으로부터 얻어진 $Cr_2O^{2-}_{7}$의 형태로 존재하리라 예측했던 것이 이소폴리의 형태로 존재함을 알 수 있었다.