• YAKHAK HOEJI
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• v.43 no.1
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• pp.48-54
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• 1999

Effects of zinc chloride (Zn) on the immune responses of lipopolysaccharide (LPS) were studied by using ICR mice. Mice were divided into 4 groups (10 mice/group), and Zn was given to the mice with i.p. injection at 0.3 mg/kg 5 times a week for 14 days, and 1 hr after Zn administration, LPS was given with i.p. injection at 5 mg/kg twice a week. Mice were immunized and challenged with sheep red blood cells (SRBC). Immunobiological responses were evaluated by humoral, cellular and nonspecific immunity. LPS treatment significantly increased the relative weights of spleen and thymus, hemagglutination titer (HA) and proliferation of splenocytes compared with those in controls, but significantly decreased the body weight gain. Zn treatment significantly increased proliferation of splenocytes and circulating leukocytes compared with those in controls. Combination of Zn and LPS significantly decreased the body weight gain and proliferation of splenocytes compared with those in controls. Combination of Zn and LPS significantly decreased HA and proliferation of splenocytes than in LPS alone. These findings indicate that zinc lowered the humoral immune responses of LPS.

• Nuclear Engineering and Technology
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• v.52 no.9
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• pp.2078-2084
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• 2020

Magnesium oxide (MgO) and Zinc oxide (ZnO) nanoparticles (NPs) have been successfully synthesized by solid-solid reaction method. The structural properties of ZnO and MgO NPs were studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD results indicated a formation of pure MgO and ZnO NPs. The mean diameter values of the agglomerated particles were around to be 70 and 50 nm for MgO and ZnO NPs, respectively using SEM analysis. Further, a wide-range of nuclear radiation shielding investigation for gamma-ray and fast neutrons have been studied for Magnesium oxide (MgO) and Zinc oxide (ZnO) samples. FLUKA and Microshield codes have been employed for the determination of mass attenuation coefficients (μ_m) and transmission factors (TF) of Magnesium oxide (MgO) and Zinc oxide (ZnO) samples. The calculated values for mass attenuation coefficients (μ_m) were utilized to determine other vital shielding properties against gamma-ray radiation. Moreover, the results showed that Zinc oxide (ZnO) nanoparticles with the lowest diameter value as 50 nm had a satisfactory capacity in nuclear radiation shielding.

• Korean Journal of Crystallography
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• v.12 no.3
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• pp.145-149
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• 2001

The hydrothermal reaction between zinc(II) nitrate Zn₃(PO₄)₂(H₂O) and potassium phosphate dibasic (K₂HPO₄) in the presence of pyrazine gave a three-dimensional zinc-phosphate coordination polymer with an empirical formula of Zn₃(PO₄)₂(H₂O) (1). Compound 1 was characterized by IR spectroscopy, and X-ray diffraction. Crystallographic data for 1: monoclinic space group. P2₁/c, a=8.970(1)Å, b=4.901(1)Å, c=16.759(3)Å, β=94.98(2)°, Z=4, R(wR₂)=0.0332(0.0927).

• Applied Biological Chemistry
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• v.20 no.2
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• pp.255-261
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• 1977

Using tracer technique of Zn-65, a pot experiment has been carried out in order to evaluate the efficiency of zinc fertilization on two paddy soils; an acidic from Kimpo and an alkaline from Yeongweol. The sources of zinc were zinc sulfate, zinc carbonate, zinc chloride and zinc oxide. Two rates of zinc were applied to the soils and control treatment was also included for this study. The methods of zinc application were uniform mixing throughout the soil, applying to the soil surface and irrigation water, and root dipping with zinc oxide at transplanting. In general, Yeongweol soil had higher efficiency of zinc fertilizers than Kimpo soil. The results showed that zinc fertilizer application should be required to improve the rice growing conditions in Yeongweol soil especially at early stage of growth after transplanting. As to the application method of zinc fertilizers, mixing treatment appeared to be most superior to any other methods in both soils. In addition, it is found that root dipping in the zinc oxide suspension would be a rather effective method of zinc application. In aspect of fertilizer efficiency there was no superiority or inferiority among the zinc sources used in this experiment.

• Journal of Oral Medicine and Pain
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• v.25 no.1
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• pp.1-7
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• 2000

The purpose of this study is to investigate effects of several zinc solutions including Artemisia asiatica-containing zinc solution on concentration of oral volatile sulfur compounds(VSCs). We determined the VSCs concentration of breath of human subjects before and after use of zinc solutions(O.25% $ZnF_2$ Artemisia asiatica-containing 0.25% $ZnCl_2$ and Artemisia asiatica-containing 0.25% $ZnCl_2$ solutions) The results were as follows : 1. 0.25% $ZnCl_2$ solution was more effective than 0.25% $ZnF_2$ solution in reducing the concentration of oral VSCs and the maintenance duration of effectiveness. 2. Artemisia asiatica-containing 0.25% $ZnCl_2$ solution was more effective than Artemisia asiatica-containing 0.25% $ZnF_2$ solution in reducing the concentration of oral VSCs and the maintenance duration of effectiveness. 3. Artemisia asiatica-containing 0.25% $ZnF_2$ solution and 0.25% $ZnF_2$ solution showed no significant difference in reducing the concentration of oral VSCs and the maintenance duration of effectiveness but, Artemisia asiatica-containing 0.25% $ZnF_2$ solution was slightly more effective. 4. Artemisia asiatica-containing 0.25% $ZnCl_2$ solution and 0.25% $ZnCl_2$ solution showed no significant difference in reducing the concentration of oral VSCs and the maintenance duration of effectiveness but, Artemisia asiatica-containing 0.25% $ZnF_2$ solution was slightly more effective.

• The Korean Journal of Food And Nutrition
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• v.8 no.3
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• pp.230-238
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• 1995

Iron and zinc were bound by neutral detergent fiber (NDF) obtained from 15 kinds of vegetables being consumed commonly in Korea. Binding capacity of Fe and Zn of NDF ranged from 37.8% to 85.5% and from 81% to 25.5%, respectively showing higher binding capacity of Fe to NDF than of Zn. Both Fe and Zn binding capacity of NDF increased as pH increased and reached to a maximum at pH 7 In all vegetables. The amount of mineral (Fe and Zn) bound to NDF increased as mineral concentration Increased.

• Preventive Nutrition and Food Science
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• v.22 no.1
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• pp.1-8
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• 2017

About 20 chemical elements are nutritionally essential for humans with defined molecular functions. Several essential and nonessential biometals are either functional nutrients with antidiabetic actions or can be diabetogenic. A key question remains whether changes in the metabolism of biometals and biominerals are a consequence of diabetes or are involved in its etiology. Exploration of the roles of zinc (Zn) in this regard is most revealing because 80 years of scientific discoveries link zinc and diabetes. In pancreatic ${\beta}$- and ${\alpha}$-cells, zinc has specific functions in the biochemistry of insulin and glucagon. When zinc ions are secreted during vesicular exocytosis, they have autocrine, paracrine, and endocrine roles. The membrane protein ZnT8 transports zinc ions into the insulin and glucagon granules. ZnT8 has a risk allele that predisposes the majority of humans to developing diabetes. In target tissues, increased availability of zinc enhances the insulin response by inhibiting protein tyrosine phosphatase 1B, which controls the phosphorylation state of the insulin receptor and hence downstream signalling. Inherited diseases of zinc metabolism, environmental exposures that interfere with the control of cellular zinc homeostasis, and nutritional or conditioned zinc deficiency influence the pathobiochemistry of diabetes. Accepting the view that zinc is one of the many factors in multiple gene-environment interactions that cause the functional demise of ${\beta}$-cells generates an immense potential for treating and perhaps preventing diabetes. Personalized nutrition, bioactive food, and pharmaceuticals targeting the control of cellular zinc in precision medicine are among the possible interventions.

• Nutritional Sciences
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• v.5 no.3
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• pp.155-160
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• 2002

The purpose of this study was to investigate the effects of micronutrient supplementation on the growth of preschool children in China. A double-blind, placebo-controlled trial was conducted on 156 growth retarded preschool children who were randomly assigned to the following five groups : supplemental control (S-control; n=28); zinc supplementation (＋Zn; 3.5mg Zn/day, n=34); zinc and calcium supplementation (＋ZnCa; 3.5mg Zn ＋ 250mg Ca/day, n=37); zinc, calcium and vitamin A supplementation (＋ZnCaVA; 3.5mgZn ＋ 250mgCa ＋ 200gVA/day, n=28); and calcium and vitamin A supplementation (＋CaVA; 250mgCa ＋ 200gVA/day, n=29). Another 34 children of normal height were selected as a normal control (N-control). Supplementation continued for twelve months. After supplementation, the height gains in the ＋Zn group (7.84cm per year) and the ＋ZnCa group (7.70 cm per year) were significantly higher than that in the S-control group (6.74 cm per year, P＜0.05). The weight gain in the ＋ZnCaVA group (2.55kg per year) and the ＋CaVA group (2.57 kg per year) was also significantly higher than that in the S-control group (2.19 kg per year, P＜0.05). The average number of days of illness in each group taking supplements was lower than that in the S-control group (13 days per year compared with 23 days per year). No significant differences in bone maturity were observed between the groups. In conclusion, in this study Zinc and Zinc ＋ Calcium supplementation improved the height gain, and vitamin A improved the weight gain, in growth retarded preschool children, but these supplements did not affect the maturity of bone. Micronutrient supplementation also lowered the morbidity of these children.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.5
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• pp.705-710
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• 2012

An anti-reflection layer (AR) is used in the solar cell to improve the amount of the irradiated light, resulting in the improvement of the performance of the solar cell. In this study, the zinc oxide (ZnO) AR is applied to the dye-sensitized solar cell (DSC) by using zinc nitrate solution. The conditions such as solution concentration and sintering temperature for fabricating the ZnO AR are changed to optimize the performance of the AR. As a result, the best performance is shown when the zinc nitrate solution with 100mM concentration is used and the sintering temperature is $600^{\circ}C$. And then, the ZnO AR formed with these optimal conditions is applied to the DSC. Consequently, a DSC with a ZnO AR had an increased current density up to 13.86$mA/cm^2$ and an enhanced efficiency of 6.32%.

• Korean Journal of Materials Research
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• v.26 no.6
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• pp.311-319
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• 2016

In this study, an environment-friendly synthetic strategy to process zinc oxide nanocrystals is reported. The biosynthesis method used in this study is simple and cost-effective, with reduced solvent waste via the use of fruit peel extract as a natural ligation agent. The formation of ZnO nanocrystals using a rambutan peel extract was observed in this study. Rambutan peels has the ability to ligate zinc ions as a natural ligation agent, resulting in ZnO nanochain formation due to the presence of an extended polyphenolic system over the whole incubation period. Via transmission electron microscopy, successful formation of zinc oxide nanochains was confirmed. TEM observation revealed that the bioinspired ZnO nanocrystals were spherical and/or hexagonal particles with sizes between 50 and 100 nm.