• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.291.1-291.1
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• 2013

We examined the temperature-dependent structural and magnetic properties of HgI2 in the temperature range of 300~400 K. HgI2 is a diamagnetic material and can be used for X-ray or γ-ray detectors. DCmagnetization measurements on HgI2 showed that there is a small but distinguishable change in its diamagnetic properties near 375 K. The magnetic property change is not expected because Hg and I are known as nonmagnetic elements. X-ray diffraction (XRD) measurements revealed a structural transition in the temperature of 350~400 K. Temperature-dependent x-ray absorption fine structure (XAFS) demonstrated that the chemical valence states of both Hg and I did not changed in the temperature range of 300~400 K. However, XAFS revealed that the bond-length disorder was slightly increased in the temperature range, particularly, near Hg atoms. The structural changes of HgI2 are likely related to its diamagnetic property change. We will discuss the relation between the diamagnetic properties and local structural properties of HgI2 in detail.

• Biomolecules & Therapeutics
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• v.1 no.2
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• pp.131-136
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• 1993

In the present study, the effect of $HgCl_2$on the function of human peripheral polymorphonuclear leukocytes(PMNs) was examined. PMNs were isolated from human peripheral blood with density centrifugation in Ficoll-Paque. The cells were then incubated with $0.5{\sim}5{\mu}M\;HgCl_2$and glass adherence, chemotactic activity and erythrocyte-antibody rosette forming activity were measured. $HgCl_2$ decreased the function of PMNs in all three aspects tested. $HgCl_2$significantly diminished glass adherence(40.5 {\mu}M: 92{\pm}12%$ (percentage of control, $mean{\pm}$ S.D.); 41 {\mu}M: 46{\pm}11%,$ P<0.01; $3{\mu}M: 35{\pm}7%,$P<0.01;$5{\mu}M:49{\pm}10%,$ P<0.01). Similarly, significant differences were observed in chemotactic activity after $HgCl_2$treatment compared with control (control: $0.95{\pm}0.14mm; 0.5 {\mu}M: 0.91{\pm}0.11 mm; 1 {\mu}M: 0.77{\pm}0.16mm, P<0.05; 3{\mu}M: 0.61{\pm} 0.06mm, P<0.01; 5{\mu}M: 0.15{\pm}0.03 mm, P<0.01).$ Also, 4HgCl_2$decreased the percentage of rosette-forming PMNs, indicating diminished phagocytic activity of PMNs upon $HgCl_2$ exposure compared with control (control: $58{\pm}4%; 1{\mu}M: 53{\pm}4%, p<0.05; 3{\mu}M: 49{\pm}3%, P<0.01; 5{\mu}M: 46{\pm}3%, P<0.01).$ Cell viability was not antered after $HgCl_2$treatment (483{\pm}5%$ viability in control PMNs versus $81{\pm}8%$ viability in $5{\mu}M$ Hg-treated PMNs), suggesting that the impaired PMN function after $HgCl_2$treatment was not due to nonspecific cytotoxicity induced by $HgCl_2$. $HgCl_2$-induced decrease in the function of PMNs may have some implications in depressed host susceptibilityupon bacterial challenge after mercury exposure.

• Korean Journal of Materials Research
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• v.28 no.12
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• pp.732-737
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• 2018

We develop a purification process of $Hg_2Br_2$ raw powders using a physical vapor transport(PVT) process, which is essential for the fabrication of a high performance acousto-optic tunable filter(AOTF) module. Specifically, we characterize and compare three $Hg_2Br_2$ powders: $Hg_2Br_2$ raw powder, $Hg_2Br_2$ powder purified under pumping conditions, and $Hg_2Br_2$ powder purified under vacuum sealing. Before and after purification, we characterize the powder samples through X-ray diffraction and X-ray photoelectron spectroscopy. The corresponding results indicate that physical properties of the $Hg_2Br_2$ compound are not damaged even after the purification process. The impurities and concentration in the purified $Hg_2Br_2$ powder are evaluated by inductively coupled plasma-mass spectroscopy. Notably, compared to the sample purified under pumping conditions, the purification process under vacuum sealing results in a higher purity $Hg_2Br_2$ (99.999 %). In addition, when the second vacuum sealing purification process is performed, the remaining impurities are almost removed, giving rise to $Hg_2Br_2$ with ultra-high purity. This high purification process might be possible due to independent control of impurities and $Hg_2Br_2$ materials under the optimized vacuum sealing. Preparation of such a highly purified $Hg_2Br_2$ materials will pave a promising way toward a high-quality $Hg_2Br_2$ single crystal and then high performance AOTF modules.

• Journal of Yeungnam Medical Science
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• v.4 no.1
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• pp.123-128
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• 1987

To estimate the prevalence of hypertension among the aged in urban area, the blood pressure was examined on the subjects of 565 men and 762 women of 65 years old and older among the residents of Nam-Ku and Soosung-Ku in Taegu between January and December, 1986. The mean systolic blood pressure was $136.0{\pm}25.01mmHg$ in male and $133.0{\pm}24.56mmHg$ in female. The mean diastolic blood pressure was $83.7{\pm}14.41mmHg$ in male and $82.4{\pm}14.43mmHg$ in female. There was no significant differences between male and female in both mean systolic and diastolic blood pressure. According to WHO category, the prevalence of pure systolic hypertension (${\geq}$160/<95mmHg) was 7.8% in male and 6.8% in female. The prevalence of pure diastolic hypertension(<160/${\geq}$95mmHg) was 6.0% in male and 3.9% in female. The prevalence of both systolic and diastolic hypertension (${\geq}160/{\geq}95mmHg$) was 13.5% in male and 12.9% in female. According to joint National Committee category, the percentage of normal blood pressure (/<90mmHg) was 46.7% in male and 50.8% in female. The prevalence of mild hypertension (/90=104mmHg) was 34.5% in male and 34.6% in female. The prevalance of moderate hypertension (/105=144mmHg) was 5.1% in male and 2.5% in female. The prevalence of severe hypertension (/${\geq}$115mmHg) was 2.3% in male and 3.0% in female. The prevalence of borderline isolated systolic hypertension (140-159/<90mmHg) was 9.0% in male and 6.6% in female. The prevalence of isolated systolic hypertension (${\geq}$160/<90mmHg) was 2.3% in male and 2.5% in female.

• Journal of Photoscience
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• v.1 no.1
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• pp.47-52
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• 1994

Effects of HgCl$_2$-treatment on electron transport, chlorophyll a fluorescence and its quenching were studied using isolated barley (Hordeum vulgare L. cv. Albori) chloroplasts. Depending on the concentration of HgCI$_2$, photosynthetic oxygen-evolving activities of photosystem II (PS II) were greatly inhibited, whereas those of photosystem I (PS I) were slightly decreased. The inhibitory effects of HgCl$_2$ on the oxygen-evolving activity was partially restored by the addition of hydroxyamine, suggesting the primary inhibition site by HgCl$_2$2-treatment is close to the oxidizing site of PS tl associated with water-splitting complex. Addition of 50 $\mu$M HgCI$_2$ decreased both photochemical and nonphotochemical quenching of chlorophyll fluorescence. Especially, energy dependent quenching (qE) was completely disappeared by HgCl$_2$-treatment as observed by NH$_4$CI treatment. In the presence of HgCI$_2$, F'o level during illumination was also increased. These results suggest that pH gradient across thylakoid membrane can not be formed in the presence of 0 $\mu$M HgCl$_2$. In addition, antenna pigment composition might be altered by HgCl$_2$-treatment.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.345-353
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• 1983

The polyurethane foam impregnated with 5, 7-dibromo-8-hydroxyquinoline (DBHQ) has been studied to be applied to the quantitative adsorption and recovery of Hg(II) from the aqueous solutions. The adsorption of Hg(II) by DBHQ-OPP foam is due to the chelation between DBHQ-OPP foam and Hg(II) on the foam, forming each colored insoluble chelate with 1:2 mole ratio. The optimum experimental conditions for the adsorption of Hg(II) has been determined. The quantitative recovery of Hg(II) adsorption by the OPP foam and reuse of DBHQ-OPP foam were investigated. Hypothesis on the adsorption and separation mechanism of Hg(II) and DBHQ to the polyurethane foam was proposed.

• Journal of the Korean Chemical Society
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• v.34 no.5
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• pp.438-444
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• 1990

Observed rate constants (k$_{obs.}$) for Hg$^{2+}$-catalysed aquation of cis-[Co(en)$_2$(OH$_2$)Cl]$^{2+}$, [Co(NH$_3$)$_5$Cl]$^{2+}$, cis-[Co(NH$_3$)$_4$(OH$_2$)Cl]$^{2+}$, and [Co(NH$_2$CH$_3$)$_5$Cl]$^{2+}$ were measured at various concentrations of Hg$^{2+}$. The k$_{obs.}$ was increased with increasing the concentrations of Hg$^{2+}$. The k$_{obs.}$ were related to mechanistically derived rate constants by the relationship; Rate = k$_2$K[complex][Hg$^{2+}$]. Various mixed aqueous-organic solvent have been successfully employed for Hg$^{2+}$-catalysed aquation of octahedral myetal complexes. From the slope of the plot of log k againt Y (solvent ionizing power), the mechanism on the aquation of Co(Ⅲ) complexes by Hg$^{2+}$ has been suggested to be I$_d$-mechanism. The change in a rate on aquation of each Co(Ⅲ) complex was related to the ligand field parameters (${\Delta}$), for Co(Ⅲ) complexes.

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.2
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• pp.91-97
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• 2006

The intraocular pressure for Korean youth were measured by using tonometer (AT555-Reichert). The relative frequency distributions of intraocular pressures have been studied for samples of 1,027 persons(475 males, 552 females). The most commonly recorded IOP for both men and women was around 14.5mmHg and 17.5mmHg, respectively. They were in the range of 7 to 23mmHg(males) and 7 to 22mmHg(females). The median pressure(cumulative frequency=0.5%) is 13.0~16.5mmHg for males and 16.5~18.5mmHg for females, so the values for females are slightly higher than males. The mean pressure is 15.2mmHg for males and 15.8mmHg for females, respectively. The 98% of population was in the range of the normal IOP. There are long-term diurnal variation in mean intraocular pressure and the IOP was decreased as a function of time from morning to night. The measured IOP was affected by several factors: exercise made to decrease the IOP and tight collars, dark places and posture of decubitus position got to elevate the IOP.

• The Korean Journal of Ecology
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• v.22 no.2
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• pp.89-94
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• 1999

Thirty-day-old seedlings of tomato (Lycopersicon esculentum) were treated with different concentrations of HgCl$_2$(0. 10 and 50 $\mu$M) for up to 20 days. and the detailed distribution of Hg absorbed and its toxicity in different plant parts (roots, stems and leaves) were investigated. The accumulation of Hg in plants increased with external Hg concentrations. and Hg is strongly retained by roots. Further. Hg content in leaves was various. showing more accumulation in older leaves. Seedlings exposed to toxic levels of Hg showed not only the reduction of dry weight and length of both shoot and root. and chlorophyll levels in leaves but also the enhancement of malondialdehyde (a lipid peroxidation product) formation in all plant parts investigated. These results suggest that physiological impairment of a plant exposed to Hg may be achieved by internal distribution of Hg absorbed and Hg-induced oxidative stress in different plant parts.

• Journal of Environmental Health Sciences
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• v.26 no.4
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• pp.88-96
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• 2000

The aim of the current study was to evaluate the transport system in EMT-6 cell for the uptake of the methylmercury(MeHg). Several inhibitors ere used to test used to test which potential transport system might be involoved in MeHg uptake. Probenecid was used to test the organic transport system, valinomycin for testing the effect of the membrane potential, cytochalasin B for testing the facilitated diffusive D-glucose transport system and colchicine for testing the microtubule system. Ouabain for evaluating active transport system, 4',4-diisothiocyano-2',2-stilbenedisulfonic acid(DIDS) the Cl- ion transport system and verapamil for the $Ca^{2+}$ transprot system. Significantly, MeHg decreased the synthesis of nitric oxcide(NO) and intracellular ATP in ENT-6 cells. In the condition of ouabain containing with MeHg decreased the production of NO and intracelluar ATP. In the treatment of inhibitors, ouabain showed protective effect against cytotoxicity of MeHg but ather inhibitors not showed protective effects. The protective effects of ouabain against the cytotoxicity of MeHg deoended on the concentration of added ouabain to the culture medium for MET-6 cells. These result showed that the uptake of MeHg might be involved in the active transport system. Active transports system seems to share similarities with the transport systems for the uptake of MeHg when using MeHg and MeHg-glutathione complex.x.