• Journal of Environmental Science International
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• v.23 no.1
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• pp.61-68
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• 2014

This study attempted to utilize various groundcover plants in phytoremediation, using shade plants, which often have a high shade tolerance for shade urban space. Liriope platyphylla was grown in soil containing three of heavy metals, Zn, Cd, and Pb under four different concentrations (0, 100, 250 and 500 mg/kg) to determine the heavy metal accumulation characteristics and removing from soil. Total amounts of accumulated Zn in L. platyphylla were increased in accordance with increasing elevated Zn concentrations in soil, but the difference was not significant between Zn250 and Zn500. Cd accumulation, sharply increased in Cd100 and Cd250, but was reduced in Cd500. Increased Pb concentration in soil resulted a continuous increase in the total amounts of Pb accumulated in L. platyphylla. The total content of Zn in soil decreased by almost 50% in Zn100, almost 33% in Zn250 and 20% in Zn500 through growth of L. platyphylla over a period of 7 months. In the case of Cd, the concentration in soil, was decreased with 10% in Cd100, 10% in Cd250 and 33% in Cd500 through growth of L. platyphylla over a period of 7 months. This results indicate that more Cd was removed by planting L. platyphylla, compared to Zn or Pb.

• Korean Journal of Materials Research
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• v.28 no.2
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• pp.101-107
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• 2018

Li-incorporated ZnO thin films were deposited by using ultrasonic-assisted spray pyrolysis deposition (SPD) system. To investigate the effect of Li-incorporation on the performance of ZnO thin films, the structural, electrical, and optical properites of the ZnO thin films were analyzed by means of X-ray diffraction (XRD), field-emssion scanning electron microscopy (FE-SEM), Hall effect measurement, and UV-Vis spectrophotometry with variation of the Li concentraion in the ZnO sources. Without incorporation of Li element, the ZnO surface showed large spiral domains. As the Li content increases, the size of spiral domains decreased gradually, and finally formed mixed small grain and one-dimensional nanorod-like structures on the surface. This morphological evolution was explained based on an anti-surfactant effect of Li atoms on the ZnO growth surface. In addition, the Li-incorporation changed the optical and electrical properties of the ZnO thin films by modifying the crystalline defect structures by doping effects.

• Journal of the Korean Ceramic Society
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• v.24 no.5
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• pp.461-469
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• 1987

Single crystals of Mn-Zn Ferrite were grown by slow cooling method using Na2B4O7 as flux agent. The effects of flux content and cooling rate on the types of crystals, and the relation between supersaturation and growth mechanism were studied. As a result, the types of grown crystals occurred as plate, hopper and octahedral crystals. The occurrence of these crystal types was dependent on flux content. The habit was found to correlate with the growth rate and supersaturation. The lateral growth of a dendritic crystal is related to the twin layer. The growth of crystals from borax melts mainly occurred by the layer-spreading growth following corner and edge nucleation caused by high supersaturation in the melt. Especially, the plate crystals were produced on top of the melts. The hopper and octahedral crystals occurred at lower supersaturation than the plate crystals.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1989.06a
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• pp.56-58
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• 1989

All-polycrystalline Cd$_1$-xZnxS/CdTe solar cells have been fabricated by coating CdTe slurries with 4.5 wt% of CdCl$_2$on the sintered Cd$_1$-xZnxS films and by sintering CdTe layer at 6$25^{\circ}C$ for lh in nitrogen atmosphere. Solar efficiency of the sintered Cd$_1$-xZnxS/CdTe solar cells increases as the Zn content increases up to x=0.06 and then decreases with further increase in the Zn content. A solar efficiency of 12.5% under a solar intensity of 76mW/$\textrm{cm}^2$ was observed in a Cd 0.94 Zn0.06S/CdTe solar cell. By optimizing the amount of CdCl$_2$in the slurry and sintering conditions, it is possible to produce Cd$_1$-xZnxS/CdTe solar cells with efficiency higher than 12%.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1495-1497
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• 1998

The effects of lanthania on the microstructure and electrical characteristics of Pr-based ZnO varistors were investigated. The average grain size was increased in the range of 21.9$\sim$56.3${\mu}m$ with increasing lanthania content(0.0$\sim$2.0mol%). La was largely segregated at the grain boundary. As lanthania content increases, threshold voltage and nonlinear coefficient were decreased and leakage current was increased. In particular 2.0mol% lanthania-added varistor exhibited low threshold, voltage 17.0V/mm and nonlinear coefficient of around 6. Based on these results, this varistor can be said to be used as low-voltage varistor, if nonlinear coefficient is somewhat improved forward.

• Korean Journal of Pharmacognosy
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• v.13 no.3
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• pp.102-105
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• 1982

Nine trace elements in Bear Galls(Fel Ursi) studied in this paper are Na, Mg, K, Ca, Cu, Zn, Fe, Pb and Ge. The contents of Na, Mg, K, Ca, Cu, Zn, Fe, Pb are determined by atomic absorption spectrometry and Ge is determined by graphite atomic absorption spectrometry. In both methods, the sample is digested with nitric-perchloric acid and then ashed. The results of analysis are shown in table and the result obtained from this study are as follows. a. The highest content of trace element of Bear Gall is Na and other elements are getting lower in order of K, Mg, Ca, Ge, Zn, Fe, Cu, and Pb. b. Particularly the content of Ge in Bear Gall was determined.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.828-830
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• 1988

This paper considered temperature-sensitive characteristics on the basis of curie tempeature and quenching method in the process of manufacturing Mn-Cu-Zn Fersite. The results are as follow. Curie tempeature drops according as the content of CuO and ZnO increases. It also decreases according as sintering temperature increases when the content of ZnO in fixed. Curie temperature drops more in quenching than in slow cooling and activation energy diminishes were too. On the basis of curie tempeature, activation energy is greater in paramagnetic region than in ferrimagnetic region. As its voltage-crrent characteristics is similar to that semiconductors, the temperature-sensitive ferrite is expeated to be appied in the area of power electronics.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.8
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• pp.601-606
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• 1998

ZnO thin film had been deposited on the glass by sputtering method, and the electrical and structural properties were investigated. When the rf power was 180W and sputtering was 10 m Torr at room temperature, Al-doped ZnO thin film had the lowest resistivity(1$\times10^{-4}\Omega\cdot{cm}$) and then carrier concentration and Hall mobility were $6.27\times10^{20} cm^{-3} and 22.04 cm^2/V\cdot$s, respectively. The undoped ZnO thin film had about 10$\times10^{14}\Omega\cdot cm$ resistivity when oxygen content was 10% or more at room temperature. When the oxygen content was 50% and below and sputtering pressure was 1.0$\times$1.0 \ulcorner Torr, the surface morphology of thin film observed by SEM was overall uniform.

• Journal of Ginseng Research
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• v.7 no.1
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• pp.74-79
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• 1983

Effect of soil moisture on content and partition of mineral nutients in panax ginseng (2 years old) was investigated. Similarity was found between N and p, Ca and Mg, K and Fe. Mn and Zn were quite different each other and from others. Nutrient partition was affected more by nutrient content than by dry matter. Under suboptimal moisture condition partition to shoot was inhibited in order of Mg, Zn, Ca, Mg, N and P while accelerated in odor of Fe. K and Mn. Under supraoptimal moisture condition Partition to shoot was inhibited in order of Zn, Fe, K, and Ca, while accelerated in order of Mg, N, Mn and p.

• Journal of Animal Science and Technology
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• v.56 no.8
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• pp.29.1-29.6
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• 2014

This study compared the effects of varying lipid content and dietary concentration of a lipid-encapsulated (LE) ZnO product to those of native ZnO and thereby to find insights into optimal lipid coating and dosage of the Zn supplement. A total of 192 21-d-old weanling pigs were allotted to 48 pens, after which each six pens received a ZnO-free basal diet supplemented with 125 ppm ZnO (100 ppm Zn; BASAL), 2,500 ppm Zn as native ZnO (HIGH), or 100 or 200 ppm Zn as LE ZnO (LE-100 or LE-250) containing 8%, 10%, or 12% lipid [LE-8%, LE-10%, or LE-12%, respectively; $2{\times}3$ factorial arrangement within the LE-ZnO diets (LE-ALL)] for 14 d. Forty pigs were killed at the end for histological and biochemical examinations. None of ADG, ADFI, gain:feed, and fecal consistency score differed between the LE-ALL and either of the BASAL and HIGH groups. Hepatic and serum Zn concentrations were greater (p <0.05) in the HIGH vs. LE-ALL group, but did not differ between LE-ALL and BASAL, between LE-100 and -250, or among LE-8%, -10%, and -12% groups. Villus height (VH), crypt depth (CD), and the VH:CD ratio in the duodenum, jejunum, and ileum did not differ between the LE-ALL and either of the BASAL and HIGH groups, except for a greater CD in the duodenum in the LE-ALL vs. HIGH group. Additionally, VH and CD in the duodenum and VH:CD in the jejunum were greater in the LE-250 vs. LE-100 group. Specific activities of sucrase, maltase, and leucine aminopeptidase in these intestinal regions and those of amylase and trypsin in the pancreas were not influenced by the lipid content or dietary concentration of LE ZnO and also did not differ between the LE-ALL and either of the BASAL and HIGH groups, except for a greater pancreatic amylase activity in the former vs. HIGH group. In conclusion, the present results indicate that the LE ZnO, regardless of its lipid percentage or supplementation level examined in this study, has no significant effect on growth performance, fecal consistency, or digestive enzyme activities of weanling pigs under the experimental conditions.