• Journal of the East Asian Society of Dietary Life
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• v.14 no.1
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• pp.27-33
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• 2004

The objectives of the present study were to measure the content of iron, copper and zinc in human milk and to estimate the intake of iron, copper and zinc of breast-fed infants during the early period of lactation. Twenty-five lactating women who delivered in a hospital in Seoul volunteered for the study. Milk samples were collected at day 2, 3, 4, 5, 6, 7, 15 and 30 postpartum. The contents of iron, copper and zinc were determined using the atomic absorption spectrophotometer after wet digestion. The intakes of iron, copper and zinc of infants were estimated by multiplization with the infant milk intake reported in our laboratory. The content of iron was 0.58 $\mu\textrm{g}$/g in colostrum, 0.48 $\mu\textrm{g}$/g in transitional milk and 0.39 $\mu\textrm{g}$/g in mature milk while the estimated iron intake of infants was 271, 255 and 259 $\mu\textrm{g}$/day, respectively. The content of copper in the milk was 0.45 $\mu\textrm{g}$/g in colostrum, 0.43 $\mu\textrm{g}$/g in transitional milk and 0.33 $\mu\textrm{g}$/g in mature milk while the estimated copper intake of infants was 210, 229 and 220 $\mu\textrm{g}$/day, respectively. The content of zinc in the milk was 5.24 $\mu\textrm{g}$/g in colostrum, 3.70 $\mu\textrm{g}$/g in transitional milk, 2.93 $\mu\textrm{g}$/g in mature milk while the estimated zinc intake of infants was 2452, 1968, and 1949 $\mu\textrm{g}$/day, respectively. These results suggest that copper and zinc intake of infants are met to RDA but iron is not.

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.2
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• pp.97-103
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• 1999

Zinc sulfide is a ll-VI compound with a large direct band gap in the near-UV region and a promising material for blur-light emitting diode and laser diode. It was identified that the structure had zinc blonde structure through the analysis of X-ray diffraction patterns. It's lattice constant was measured to be $a_o=5.411{\AA}$. The optical absorption, photocurrent, and photoluminescence spectra were measured to investigate the optical properties of zinc sulfide single crystal. The optical energy band gap measured at room temperature was 3.61eV The energy band gap of zinc sulfide annealed in zinc vapor at $800^{\circ}C$ was lower 0.1eV than that of as-grown zinc sulfide through the analysis of the photocurrent spectra. The photoluminescence spectra were measured ranging from 30K to 293K for the two cases of as-grown and annealed zinc sulfide. As-grown ZnS single crystal had peaks at 350nm, 392nm, 465nm, and annealed zinc sulfide had peaks at 349nm.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.2
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• pp.104-110
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• 2001

Structural, optical and electrical properties of Cd$_{1-x}$ Zn$_{x}$S films deposited by chemical bath deposition(CBD), which is a very attractive method for low-cost and large-area solar cells, are presented. Especially, in order to control more effectively the zinc component of the films, zinc acetate, which was used as the zinc source, was added in the reaction solution after preheating the reaction solution and the pH of the reaction solution decreased with increasing the concentration of zinc acetate. The films prepared after preheating and pH control had larger zinc component and higher optical band gap. The crystal structures of Cd$_{1-x}$ Zn$_{x}$S films was a wurtzite type with a preferential orientation of the (002) plane and the lattice constants of the films changed from the value for CdS to those for ZnS with increasing the mole ratio of the zinc acetate. The minimum lattice mismatch between Cd$_{1-x}$ Zn$_{x}$S and CdTe were 2.7% at the mole ratio of (ZnAc$_2$)/(CdAc$_2$+ZnAc$_2$)=0.4. As the more zinc substituted for Cd in the films, the optical transmittance improved, while the absorption edge shifted toward a shorterwavelength. the photoconductivity of the films was higher than the dark conductivity, while the ratio of those increased with increasing the mole ratio of zinc acetate. acetate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.542-549
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• 1995

This study was conducted to obtain accurate data on intake, excretion, apparent digestibility and balance of zinc which Korean take in habitually. This study applied to the seven high school girls from 15 to 16 years old. Their food intake, feces and urine were collected and intake and excretion of zinc in them were measured by atomic absorption spectrophotometry. The measurement continued for four weeks while they maintained their normal living pattern and body weight. Each girl's daily intake and excretion of zinc were measured and apparent digestibility and balance were also studied. Each girl's daily mean intake, fecal excretion and apparent digestibility of zinc were $9.26{\pm}2.30mg,\;3.31{\pm}2.15mg,\;and\;62.92{\pm}3.22%$, respectively. The urinary excretion of zinc was $3.23{\pm}1.03mg$ and showed the positive balance of $2.61{\pm}2.91mg$.

• Textile Coloration and Finishing
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• v.30 no.3
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• pp.159-167
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• 2018

Here we designed and synthesized new zinc phthalocyanines and structures were fully confirmed by spectral and elemental analysis. All phthalocyanines have a very good solubility in industrial solvents like chloroform, dichloromethane, dimethyl sulfoxide, N,N-dimethyl formamide, propylene glycol monomethyl ether acetate (PGMEA), acetone, tetrahydrofuran and acetonitrile. UV-Visible absorption and transmittance in PGMEA showed that these dyes have suitable spectral properties for LCD color filters. By Triton X surfactant study, we confirmed that these dyes are not showing any aggregation in PGMEA. We dissolved the all phthalocyanines in LCD fabricating solvent (PGMEA), and all phthalocyanines showed more than 8 wt% of solubility. Finally, all of these results concluded that PCK1, PCK2 and PCK3 are fit for LCD green color filter.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.346.2-346.2
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• 2014

To use the GaN based light-emitting diodes (LEDs) as solid state lighting sources, the improvement of light extraction and internal quantum efficiency is essential factors for high brightness LEDs. In this study, we suggested the new materials system of a zinc tin oxide (ZTO) layer formed on blue LED epi-structures to improve the light extraction. ZTO is a representative n-type oxide material consisted of ZnO and SnO system. Moreover, ZTO is one of the promising oxide semiconductor material. Even though ZTO has higher chemical stability than IGZO owing to its SnO2 content this has high mobility and high reliability. After formation of ZTO layer on p-GaN layer by using the spin coating method, structural and optical properties are investigated. The x-ray diffraction (XRD) measurement results show the successful formation of ZTO. The photoluminescence (PL) and absorption spectrum shows that it has 3.6-4.1eV band gap. Finally, the light extraction properties of ZTO/LED chip using electroluminescence (EL) measurement were investigated. The experimental and theoretical analyses were simultaneously conducted.

• Journal of Photoscience
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• v.4 no.3
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• pp.113-119
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• 1997

The synthesis and excited-state dynamics are described for a tetrad (ZC - ZP - ZP - I) consisting of zinc chlorin (ZC), zinc porphyrin (ZP), zinc porphyrin (ZP), and pyromellitimide (I), which upon photoexcitation provides a fully charge-separated state (ZC$^+$- P - ZP - l$^- $) with lifetimes of 230 $\mu$s in THF and > 50$ \mu$s in DMF at room temperature via a stepwise electron-transfer relay that has been detected by the ps-time resolved transient absorption spectroscopy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.894-899
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• 2001

Intakes and excretions of zinc and copper were determined for 8 female adolescents (aged 16.4$\pm$0.5 y; body mass index 20.4$\pm$1.3kg/$m^2$; body fat 33.3$\pm$2.5%; bone mineral density of lumbar spine in L2-L4; 0.96$\pm$0.08g/$\textrm{cm}^2$) when they consumed diets basal and high in calcium for 6 days each. All subjects consumed a basal Ca diet containing 800 mg, Korean RDA level of the subjects, and a high Ca diet containing 1200mg, RDA plus 2 SDs of calcium intake. The diets provided 58% of energy intake as carbohydrate, 25% as fat, and 17% as protein. Food, urine and fecal samples were collected during the last 3 days of each feeding period and were assayed. Mean daily intakes on the basal and high calcium diets, respectively, were 6.57 and 6.37 mg for zinc and 910 and 812 $\mu\textrm{g}$for copper. Fecal excretion of copper and zinc in relation to intake was significantly greater on the high calcium than on the basal calcium diet. Hence, apparent absorption rate was significantly lowered from 98.7% on the basal calcium diet to 97.9% on the high calcium diet for zinc from 66.3% to 56.4% for copper, respectively. Urinary loss of copper was not detectable but that of zinc was 0.38mg on the basal diet and 0.47mg on the high calcium diet. Copper retention was 899$\pm$105$\mu\textrm{g}$/day on the basal calcium diet and 792$\pm$20.8$\mu\textrm{g}$/day on the high calcium diet, and zinc retention was 3.95$\pm$0.91mg/day and 3.11$\pm$0.89mg/day. Thus, copper and zinc retention was significantly decreased on the high calcium diet (p<0.05). Summarizing the results, apparent absorption and retention of zinc and copper were significantly decreased by calcium supplementation. Therefore, it is suggested that interactions among minerals should be considered in determining RDA.

• Rapid Communication in Photoscience
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• v.3 no.3
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• pp.50-52
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• 2014

Rotaxanes have been prepared using benzene-linked bis-porphyrin or bis-zinc porphyrin as a string component and bis-viologen as a macrocyclic ring component. Absorption and fluorescence spectra of rotaxane formed by complexation of two components have been investigated.

• Proceedings of the Korean Nutrition Society Conference
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• 1996.11b
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• pp.42-42
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• 1996