• Bulletin of the Korean Chemical Society
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• v.15 no.11
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• pp.980-984
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• 1994

Monomeric rhodium and iridium diimine complexes $Cp^*M(HNRNH)(Cp^*$ = 1,2,3,4,5-pentamethylcyclopentadienyl : (M=lr; R=o-$C_6H_4 (1a), 4,5-(CH_3)_2-C_6H_2-1,2 (1b), 4,5-(Cl)_2-C_6H_2-1,2$ (1c), NCC=CCN-1,2 (1d): M=Rh; R=NCC=CCN-1,2 (1e)) have been synthesized from $[CP^*MCl_2]_2$ and 2 equiv. of diamine in the presence of $NEt_3$. The Crystal structure of 1a was determined by X-ray diffraction method : 1a was crystallized in the monoclinic system, space group $P2_{1/c}$, with lattice constants a=9.543 (1) ${\AA}$, b=16.286 (1) ${\AA}$, c=10.068 (1) ${\AA}$ and ${\beta}$=99.25 (1), with Z= 4. Least-squares refinement of the structure led to R factor of 0.049. The coordination sphere of rhodium and iridium can be described as a 2-legged piano-stool. All complexes are highly colored. Electrochemical studies show that 1d and 1e display quasi-reversible reduction and 1a-1c display irreversible reductions, suggesting that the acceptor orbital might be localized on the diimine ring.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.E2
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• pp.78-88
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• 2006

In order to study the characteristics of cloud, a real-scale experiment for cloud generation was carried out using an extinct vertical mine (430 m height) located in the northeastern Honshu, Japan. The dry particles generated from the three-step concentrations of NaCl solutions were used for cloud generation. The number size distributions of initial dry particles and cloud droplets were monitored by Scanning Mobility Particle Sizer (SMPS) and Forward Scattering Spectrometer Probe (FSSP) at bottom and upper sites of pit, respectively. The polymeric water absorbent film (PWAF) method was employed to measure liquid water content ($W_L$) as a function of droplet size. Moreover the chemical properties of individual droplet replicas were determined by micro-PIXE. The CCN number concentration shows the lognormal form in dependence of the particle size, while the number size distributions of droplets are bimodal showing the peaks around $9{\mu}m$ and $20{\mu}m$ for every case. In comparison to background mineral particles, right shifting of size distribution line for NaCl particles was occurred. When NaCl solutions with three-step different concentrations were neulized, $W_L$ shows the strong droplet size dependence. It varied from $10.0mg\;m^{-3}$ up to $13.6mg\;m^{-3}$ with average $11.6mg\;m^{-3}$. A good relationship between $W_L$ and cloud droplet number concentration was obtained. Both chemical inhomogeneities (mixed components with mineral and C1) and homogeneities (only mineral components or C1) in individual droplet replicas were obviously observed from micro-PIXE elemental images.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3486-3488
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• 2011

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.439-440
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• 2001

대기 중의 에어러솔 입자들은 직접적으로는 빛의 산란, 흡수 등 복사 평형에 영향을 미치며, 간접적으로는 구름 응결핵(CCN)으로 작용함으로써 알베도와 구름의 수명에 영향을 미치게 된다. 자연적인 에어러솔은 인위적 활동에 따른 황 화합물, 질소 화합물, 유기물. 매연 그리고 토양 먼지의 증가에 의해 사실상 교란되어 왔다. 인위적인 에어러솔에 의한 복사 강제력(radiative forcing)은 현재 전 지구적 평균이 -0.3~-3.5Wm$^{-2}$ 정도로 추정되며, 이것은 온실 기체에 의한 강제력인 +2.0~+2.8Wm$^{-2}$ 와 비교될 만 하다(IPCC, 1995). (중략)

• Korean journal of applied entomology
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• v.57 no.4
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• pp.339-345
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• 2018

The sugar beet cyst nematode (SBCN), Heterodera schachtii first detected in Taebaek, Gangwon-do in 2011, is one of the major plant parasitic nematodes that cause economic damage to the Chinese cabbage in highland regions. In addition, the distribution of clover cyst nematode (CCN), H. trifolii was confirmed in the highland Chinese cabbage cultivated regions in 2017. In order to investigate the spread of cyst nematodes, this study has been conducted since 2013 in the highland Chinese cabbage cultivation area. In addition, in 2017, the Real-Time PCR technique with the species-specific primer was used to investigate those two cyst nematodes and the soybean cyst nematode (SCN), H. glycines which is known for its distribution in Korea, focusing on the main production regions of highland Chinese cabbage cultivation. The number of infected fields in the Chinese cabbage plantation in highland increased every year to confirm distribution in Taebaek, Samcheok, Jeongseon and Gangneung in 2017, and the cumulative number of infection fields reached 245 by 2017. Of the 41 possible cyst nematode samples for PCR analysis, 61% were CCN, only 9.8% of the SBCN and 29.3% of the SCN were identified. Therefore, some of the previously known SBCN or CCN discoveries are likely to have been infected with SCN. It is believed that the CCN needs to be controlled in the future as CCN have been found to be dominant species in the highland Chinese cabbage plantation regions.

• Journal of Life Science
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• v.23 no.2
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• pp.207-212
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• 2013

In this paper, we investigated whether resveratrol could induce the expression of cysteine-rich angiogenic inducer 61 (CYR61), which is a member of the CCN families. We showed that resveratrol up-regulated CYR61 protein expression in three different human colorectal cancer cell lines. In addition, resveratrol induced CYR61 protein expression in a dose- and time-dependent manner in a HCT116 cell line. To investigate the relationship between various biological activities of resveratrol and CYR61 expression, HCT116 cells were incubated with several NSAIDs, antioxidants, or resveratrol. Interestingly, resveratrol only induced CYR61 protein expression. The expression of CYR61 was not related to the presence of p53. A promoter assay revealed that the 786-bp promoter region (-732/+54) contains a regulatory region and that indole-3-carbinol and 6-gingerol could not induce CYR61 expression. In conclusion, our results indicate up-regulation of CYR61 is extremely resveratrol specific. The results can help to shed light on the unique biological function of resveratrol.

• Atmosphere
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• v.23 no.3
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• pp.321-329
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• 2013

This study examines the effect of aerosols on the vertical invigoration of continental stratiform clouds, using a dataset of Atmospheric Radiation Measurement (ARM) Intensive Operational Period (IOP, March 2000) at the Southern Great Plains (SGP) site. To provide further support to our observation-based findings, the weather research and forecasting (WRF) sensitivity simulations with changing cloud condensation nuclei (CCN) concentrations have been carried out for the golden episode over SGP. First, cross correlation between observed aerosol scattering coefficient and cloud liquid water path (LWP) with a 160-minutes lag is the highest of r = 0.83 for the selected episode, which may be attributable to cloud vertical invigoration induced by an increase in aerosol loading. Modeled cloud fractions in a control run are well matched with the observation in the perspective of cloud morphology and lasting period. It is also found through a simple sensitivity with a change in CCN that aerosol invigoration (AIV) effect on stratiform cloud organization is attributable to a change in the cloud microphysics as well as dynamics such as the corresponding modification of cloud number concentrations, drop size, and latent heating rate, etc. This study suggests a possible cloud vertical invigoration even in the continental stratiform clouds due to aerosol enhancement in spite of a limited analysis based on a few observed continental cloud cases.

• Atmosphere
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• v.18 no.4
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• pp.459-474
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• 2008

Aerosol scattering coefficients for three different wavelengths ($\lambda$=450,550,700 nm) are measured almost continuously by a nephelometer in Seoul for a period of 13 months (February 2007-February 2008), which includes two weeks break in August 2007 for measurements at Daegwallyeong and YoungJongdo. The mean of the daily average scattering coefficients at $\lambda$=550 nm is $194.1{\pm}144.2Mm^{-1}$ and the minimum and maximum are $14.3Mm^{-1}$ and $998.1Mm^{-1}$, respectively. The scattering coefficient shows a general increasing trend with atmospheric relative humidity (RH). When the data are classified according to weather conditions, the days with no major weather events show the smallest scattering coefficient and also the lowest RH. Surprisingly haze/fog days show the largest scattering coefficient and Asian dust days comes in second. Although the variation is large within a season, winter shows the largest and autumn shows the smallest scattering coefficient. The average ${\AA}ngstr{\ddot{o}}m$ exponent is $1.40{\pm}0.32$ for the entire Seoul measurement. As expected, Asian dust days show the smallest ${\AA}ngstr{\ddot{o}}m$ exponent and haze/fog days are the next, suggesting more efficient hygroscopic growth of aerosols for this weather condition. Aerosol scattering coefficient seems to show better correspondence with CCN concentration rather than total aerosol concentration, which may indicate that CCN active aerosols are also good scattering aerosols.

• Journal of the Korean Chemical Society
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• v.37 no.6
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• pp.599-603
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• 1993

Crystal structure of bis(1,2-diaminopropane)palladium(II) bis(oxalato)palladate(II) has been determined by X-ray crystallography. Crystal data: $Pd_2C_{10}H_{10}N_{4}O_{8}$, $M_W$ = 573.09, orthorhombic, space group $P_{ccn}$ (No = 56), a = 16.178(5), b = 16.381(6), c = 6.685(2)$\{AA}$, V = 1771.6 $\{AA}^3$, $M_W$W = 573.09, $D_c$ = 2.014 g${\cdot}c\;m^{-3}$, Z = 4, T = 294K, F(000) = 1056.0 and $\mu$ = 20.466 c$m^{-1}$. The intensity data were collected with $Mo-K\alpha$ radiation (${\lambda}$ = 0.7107 $\AA)$ on an automatic four-circle diffractometer with a graphite monochromater. The structure was solved by Patterson method and refined by full matrix least-squares methods using Pivot weights. The final R and S values were R = 0.065, $R_W = 0.059, R_{all}$ = 0.065 and S = 4.315 for 605 observed reflections. Both cation and anion complexes are essentially planar and have dihedral angle of $18(l)^{\circ}$ between thier planes. In the crystal structure, they do not have the Magnus's salt type mixed stacks; instead, the complex anions form regular stacks along the c-axis with the M-M bond length of $3.343(5)\AA$ and their stacks are surrounded by the complex cations through hydrogen bonds with the nitrogen-oxygen distances of 2.94(3) and $3.31(4)\AA.$

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.803-809
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• 2009

Notable blue shifts of the ν2 $C{\equiv}N$ stretching, $_{v4}$ C-C stretching and $_{v8}$ CCN deformation bands of $CD_3CN$ are observed upon solvation of $InCl_3$, resulting from the donor-acceptor interaction. The Raman spectrum in the $_{v2}$ region shows further details; at least two new bands emerge on the blue side of the $_{v2}$ band of free $CD_3CN$, whose relative intensities vary with concentration, suggesting that there exist at least two different cationic species in the solution. The strong hydrogen bonds formed between the methyl group and ${InCl_4}^-$ result in a large band appearing on the red side of the ν1 $CD_3$ symmetric stretching band. The solvation number of $InCl_3$, determined from the Raman intensities of the $C{\equiv}N$ stretching bands for free and coordinated $CD_3CN$, increases from $\sim$1.5 to $\sim$1.8 with decreasing concentration.