• 대한화학회지
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• 제24권1호
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• pp.8-14
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• 1980

메틸클로로휘메이트, $CH_3O$(CO)Cl와 메틸티오노클로로휘메이트, $CH_3O$(CS)Cl 및 메틸티올클로로휘메이트, $CH_3S$(CO)Cl의 가용매분해반응속도상수를 아세톤-물 및 아세토니트릴-물혼합용매중에서 전기전도도법으로 측정했으며 활성화파라미터, ${\Delta}H^{\neq}$ 와 ${\Delta}S^{\neq}$를 구하였다. 그 결과로 물함량이 큰 영역에서는 속도순위가 $$CH_3O(CO)Cl 이며, 한편 dipolar aprotic solvent가 큰 부분에서는 속도의 순위가 거꾸로 임을 알았다. log k대 solvent parameter인 Y, $\frac{D-1}{2D+1}$ 와 log($H_2$) 의 plots는 물함량이 큰 부분에서 $S_N1$ 성격이 증가함을 보여준다. 물함량이 큰 영역에서 $CH_3O$(CO)Cl은 $S_N2$로 $CH_3O$(CS)Cl은 중간정도의 메카니즘으로 반응하나 $CH_3S$(CO)Cl은 $S_N1$ 메카니즘으로 반응함을 알았다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제8권3호
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• pp.23-29
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• 2003

Setschenow constants of six alkali and alkaline earth metal-based electrolytes (i.e., NaCl, KCl, CaCl$_2$, K$_2$SO$_4$, Na$_2$SO$_4$, NaClO$_4$) for three polycyclic aromatic hydrocarbons (PAHs) (i.e., naphthalene, pyrene, and perylene) were investigated to evaluate the influence of a variety of inorganic salts on the aqueous solubility of PAHs. Inorganic salts showed a wide range of K$\_$s/ values (L/mol), ranging from 0.1108 (NaClO$_4$) to 0.6680 (Na$_2$SO$_4$) for naphthalene, 0.1071 (NaClO$_4$) to 0.7355 (Na$_2$SO$_4$) for pyrene, and 0.1526 (NaClO$_4$) to 0.8136 (Na$_2$SO$_4$) for perylene. In general, the salting out effect of metal cations decreased in the order of Ca$\^$2+/>Na$\^$+/>K$\^$+/. The effect of SO$_4$$\^$2-/>Cl$\^$-/>ClO4$\^$-/ was observed for anions of inorganic salts. The K$\_$s/ values decreased in the order of perylene>pyrene>naphthalene for K$_2$SO$_4$. However, the order of decreasing salting out effect for NaCl, KCl, CaCl$_2$, and NaClO$_4$ was perylene>naphthalene>pyrene. Hydration free energy of the 1:1 and 2:1 alkali and alkaline earth metal-based inorganic salts solution was observed to have a meaningful correlation with Setschenow constants. Thermodynamic interactions between PAH molecules and salt solution can be of importance in determining the magnitude of salting out effect for PAHs at a given salt solution.

• 대한환경공학회지
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• 제34권11호
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• pp.743-750
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• 2012

$ClO_{2(aq)}$ 분석 방법 중 하나인 UV 흡수법은 여러 염소종이 함유된 용액에서는 흡수 파장 겹침 현상으로 분석에 어려움이 있다. 이러한 문제를 극복하고자 UV 파장 분해법을 이용한 다양한 염소종이 함유된 용액의 $ClO_{2(aq)}$ 농도 정량법을 제안하였다. UV 파장 분해법을 이용한 $ClO_{2(aq)}$ 농도 값은 적정법을 이용한 $ClO_{2(aq)}$ 농도 값과 10%내에서 일치하였다. 따라서 다양한 염소 종들이 포함된 시료에서도 제안된 UV 파장 분해법을 적용한다면 $ClO_{2(aq)}$의 선택적 분석이 가능하다는 것을 알 수 있었다.

• 전자공학회논문지D
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• 제36D권4호
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• pp.56-62
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• 1999

본 연구에서, (Ba,Sr)TiO\sub 3\ 박막이 rf 전력, dc 바이어스 전압 및 반응로 압력과 같은 식각 공정 변수를 변화하여 ICP에서 Cl\sub 2\Ar 가스 혼합비에 따라 식각되었다. 0.2의 Cl\sub 2\/(Cl\sub 2\+Ar) 가스 혼합비, 600 W의 rf 전력,250 V의 dc 바이어스 전압 및 5 mTorr의 반응로 압력의 공정 조건하에서 식각율은 56nm/min이었다. 이때 Pt, SiO\sub 2\ 막에 대한 BST 박막의 식각 선택비는 각각 0.52, 0.43이었다. 식각된 BST 박막의 표면반응은 XPS로 분석하였다. Ba는 BaCl\sub 2\ 와 같은 화학적인 반응과 물리적인 스퍼터링에 의해 제거되었다. Sr의 제거는 Sr과 Cl의 화확적인 반응보다 Ar 이온 충격이 더 효과적이었다. Ti는 TiCl\sub 4\ 와 같은 화학반응에 의해 용이하게 제거되었다. XPS 분석 결과를 비교하기 위하여 SIMS의 분석을 수행하여 비교한 결과 동일한 결론을 도출하였다.

• 한국작물학회지
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• 제45권1호
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• pp.50-54
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• 2000

The elongation of mesocotyl and coleoptile plays important roles in the seedling emergence and stand establishment of dry direct-seeded rice. Experiments were carried out to elucidate the effects of seed-presoaking treatments of GA$_3$ and some inorganic salts on the mesocotyl, and coleoptile elongation of rice. Seed-soaked GA$_3$ promoted the elongation of mesocotyl, but little effect on the coleoptile elongation. The stimulation effects of GA$_3$ were found to be enhanced by addition of CaCl$_2$ However, the sole treatment of CaCl$_2$ showed no stimulating effect on the mesocotyl and coleoptile elongation. Mesocotyl elongation was most prominent in the combined treatments of 50ppm GA$_3$ with 100 mM CaCl$_2$. The synergistic effects of GA$_3$ and CaCl$_2$ on mesocotyl elongation varied with varietal groups. The stimulating effects of GA$_3$ were enhanced significantly by the addition of CaCl$_2$ in japonica varieties, Dongjinbyeo, Ilpumbyeo and Milyang 95, and tall indica variety, Labelle, but not in semidwarf Tongil type varieties, Tongilbyeo, Milyang 23, and Nampungbyeo, and semi-dwarf indica, Short Labelle. The promoting effects of GA$_3$ on the mesocotyl elongation were decreased in proportion to the lowered osmotic potential by PEG 6000 on the contrary to CaCl$_2$ This implies that the synergistic effects of CaCl$_2$ with GA$_3$ on mesocotyl elongation was not caused by osmotic potential lowered by CaCl$_2$ addition but by the salt itself. Salts such as Ca(NO$_3$)$_2$, MgCl$_2$ BaCl$_2$, NaCl, KCl and KNO$_3$ showed the synergistic effects with GA$_3$ on mesocotyl elongation as well. The degree of synergistic effects showed no differences among salts tested, implying that there is no specificity of ions constituting the salts.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.507-510
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• 2005

In winter, a large amount of de-icing salts such as $CaCl_2$, NaCl have been used on highways for road safety. They make concrete structures deteriorated. In this study, the chloride diffusion of concrete in presence of de-icing salt was investigated. The diffusion coefficient of chloride in presence of $CaCl_2$ solution was larger than in presence of NaCl solution. Therefore, it is necessary to assess chloride profile in presence of $CaCl_2$ by different way from the case in presence of NaCl solution or seawater.

• East Asian mathematical journal
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• 제32권1호
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• pp.43-46
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• 2016

The Clausen function $Cl_2$(x) arises in several applications. A large number of indefinite integrals of logarithmic or trigonometric functions can be expressed in closed form in terms of $Cl_2$(x). Very recently, Choi and Srivatava [3] and Choi [1] investigated certain integral formulas associated with $Cl_2$(x). In this sequel, we present an interesting new definite integral formula for the Clausen function $Cl_2$(x) by using a known relationship between the Clausen function $Cl_2$(x) and the generalized Zeta function ${\zeta}$(s, a). Also an interesting integral representation for the Catalan constant G is considered as one of two special cases of our main result.

• Bulletin of the Korean Chemical Society
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• 제13권2호
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• pp.162-165
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• 1992

The fine structure branching ratio and Doppler profiles of photofragment Cl ($^{2}P_{j}$) atoms from photodissociation of CINO around 236 nm in the A band have been measured by the two photon resonance enhanced multiphoton ionization technique. The measured branching ratio, $Cl^{\ast} (^{2}P_{1/2})/Cl (^{2}P_{3/2})$ is $0.18{\pm}0.02$. The Doppler profile of Cl is well reproduced assuming that one of the two components in the photofragment translational spectra reported by Haas, Felder, and Huber [Chem. Phys. Lett., 180, 293 (1990)] should correspond to Cl and that an anisotropy parameter $\beta$ for the angular distribution is 0.45. The results suggest that CINO dissociation in the A band should consist of at least two non-crossing electronic states which correlate to the formation of $Cl^* and Cl, respectively.

• 대한화학회지
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• 제37권8호
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• pp.717-722
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• 1993

물에서 [PtCl$_4$]^{2-}$의 백금(II)에 결합된 클로로리간드를 디티오카바메이트로 치환시켜 [Pt(A)], [Pt(B)$_2$]Cl$_2$, [Pt(C)$_2$] 및 [Pt(D)(CH$_2$=CH$_2$)Cl]Cl를 합성하였다. 백금 착물은 원소분석, 적외선 및 자외선-가시광선 스펙트럼과 전도도 측정을 하여 이들의 성질을 조사하였따. 이들 백금(II)의 디티오카바메이트류 착물은 물, 알코올, 디메틸술폭시드 및 티메틸포름아미드와 같은 극성용매에 잘 녹았다. 이들 백금(II) 착물의 원소분석과 물리적 측정결과에서부터 그 가능한 구조를 제시하였다.

• 방사성폐기물학회지
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• 제18권3호
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• pp.383-393
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• 2020

The corrosion behavior of Hastelloy C-276 was investigated to identify its applicability for carbon-anode-based oxide reduction (OR), in which Cl₂ and O₂ are simultaneously evolved at the anode. Under a 30 mL·min^-1 Cl₂ + 170 mL·min^-1 Ar flow, the corrosion rate was less than 1 g·m^-2·h^-1 up to 500℃, whereas the rate increased exponentially from 500 to 700℃. The effects of the Cl₂-O₂ composition on the corrosion rate at flow rates of 30 mL·min^-1 Cl₂, 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂, and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂ with a constant 170 mL·min^-1 Ar flow rate at 600℃ was analyzed. Based on the data from an 8 h reaction, the fastest corrosion rate was observed for the 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂ case, followed by 30 mL·min^-1 Cl₂ and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂. The effects of the chlorine flow rate on the corrosion rate were negligible within the 5-30 mL·min^-1 range. A surface morphology analysis revealed the formation of vertical scratches in specimens that reacted under the Cl₂-O₂ mixed gas condition.