• Journal of the Korean Ceramic Society
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• v.37 no.7
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• pp.681-685
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• 2000

The influence of ZnCl2 in portland cement hydration was studied. The hydration reaction was progressed with ZnCl2 solution to observe the adiabatic hydration exothermic and hydration products. To compare with cement hydration, Ca(OH)2 solution reacted with ZnCl2 was carried out. The addition of ZnCl2 solution to the portland cement was retarded hydration quantitatively. Because ZnO which was produced in certain pH adsorbed with unhydrated cement made retarded the hydration reaction.

• The Korean Journal of Malacology
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• v.31 no.3
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• pp.195-201
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• 2015

This study was conducted to find out concentration of trace metal, survival rate, falling rate and structural changes of abalone, Haliotis discus hannai exposed to zinc chloride. Experimental groups were composed of one control condition and four exposure conditions (0.3, 0.8, 1.3, $1.8\;ZnCl_2\;mg/L$). The accumulation of trace metal (zinc) in abalone was significantly increased all exposure group. Though the exposure groups had lower survival rate than the control group, higher falling rate than the control group. Histopathological changes in the foot, gill and hepatopancreas of abalone revealed obvious with exposure group than control group.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.33 no.1
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• pp.15-21
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• 2023

To prepare zinc oxide powder, three types of sodium-based alkali precipitants such as NaOH, Na₂CO₃, NaOH/NaHCO₃ were compared to the differences in the manufacturing process of zinc oxide powder from zinc precipitate products like intermediates with the consideration of thermodynamic reaction. The prepared zinc precipitate products by the reaction with the sodium-based alkali precipitant were confirmed to respectively hydroxy zinc chloride (Zn₅(OH)₈Cl₂·H₂O) and zinc carbonate hydroxide (Zn₅(OH)₆(CO₃)₂·H₂O) from XRD analysis. Zinc oxide particles were compared in heat treatment at 800℃ according to sodium-based alkali precipitants. The mixed NaOH and NaHCO₃ of alkali precipitant reaction was contributed to synthesize the more uniform zinc oxide particles.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.163-165
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• 1999

The study was conducted to find the critical concentrations of zinc toxicity and to determine the changes of the contents of free proline and organic acids with treatment of different zinc chloride concentrations during rice germination and seedlings grown for seven days. The concentration of zinc chloride, 140 ppm, inhibited root elongation as much as 46 times compared with the control, and the germination rate was also decreased in all treatments of zinc chloride, showing that the germination rate decreased more with increasing concentrations of zinc chloride. Its rate was only 13% with treatment of 140 ppm zinc chloride. The content of free proline with treatment of zinc chloride, 140 ppm, was highest about 4,873 $\mu$M at 3 days compared with the control. Malic acid concentration with treatment of zinc chloride, 140 ppm, increased to approximately 4 times compared to the control. Citric and succinic acid content were also slightly increased in all treatments of zinc chloride.

• Korean Journal of Materials Research
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• v.20 no.3
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• pp.111-116
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• 2010

Chloride-based fluxes such as NaCl-KCl are used in the refining of Al melt. The vapor pressure of the chloride is one of the fundamental pieces of information required for such processes, and is generally high at elevated temperatures. In order to measure the vapor pressure for chlorides, the apparatus for the transpiration method was assembled in the present study. The vapor pressure of $ZnCl_2$ and $FeCl_2$, which is related with the process of aluminum refining and the recovery of useful elements from iron and steel industry by-products, was also measured. In the measurement of vapor pressure by the transpiration method, the powder of $ZnCl_2$ or $FeCl_2$ in a alumina boat was loaded in the uniform zone of the furnace with a stream of Ar. The weight loss of $ZnCl_2$ and $FeCl_2$ after holding was measured by changing the flow rate of Ar gas (10 sccm -230 sccm), and the partial pressures of $ZnCl_2$ and $FeCl_2$ were calculated. The partial pressures within a certain range were found to be independent of the flow rate of Ar at different temperatures. The vapor pressures were measured in the temperature range of 758-901K for $ZnCl_2$ and 963-983K for $FeCl_2$. The measured results agreed well with those in the literature.

• Korean Journal of Crystallography
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• v.11 no.1
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• pp.42-45
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• 2000

The complex [Zn(L)Cl](H₂O)(ClO₄) (1) (L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,O/sup 1.18/,O/sup 7.12/]docosane) has been prepared and characterized by X-ray crystallography. 1 crystallizes in the monoclinic space group P2₁/c, with a=8.883(1), b=19.319(9), c=15.124(2)Å, β=101.65(1)°, V=2542.0(13) ų, Z=4, R₁(wR₂) for 4457 observed reflections of [I>2σ(I)] was 0.0640(0.1557). The coordination geometry around the zinc is a distorted square-pyramid with four nitrogen atoms of the macrocycle occupying the basal sites(Zn-N/sub av/=2.131(2)Å) and a chloride atom at the axial position with the Zn-Cl distance of 2.315(2)Å.

• Journal of Forest and Environmental Science
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• v.23 no.1
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• pp.51-55
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• 2007

The effect of ratio between chemical activating agent and raw material in the preparation of activated carbons from wood has been studied. Pinus koraiensis wood and zinc chloride ($ZnCl_2$) were used for materials in this study. Mixtures of wood and zinc chloride were heated under nitrogen flow in the temperature ranging from room-temperature to $600^{\circ}C$ for 1 hr using thermogravimetric technique. During heat treatment, activated carbons with various pore size and specific surface properties were obtained. The maximum BET surface area and total pore volume were $1468m^2/g$ and 1.74 cc/g, respectively, at the mixture ratio of 1 (wood powder) to 5 ($ZnCl_2$). It can be concluded that the differences in the properties of the activated carbons were related significantly with the ratio of chemical activating regent.

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1526-1530
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• 2009

Solvent extraction reaction of Zn(II) by Alamine336 from strong HCl solution up to 10 M was identified by analyzing the data reported in the literature. The equilibrium constant of this reaction was estimated by considering the complex formation between zinc and chloride ion. The necessary thermodynamic parameters, such as equilibrium constant for the formation of complexes and the interaction parameters, were evaluated from the thermodynamic data reported in the literature. The following solvent extraction reaction and the equilibrium constant was obtained by considering the activity coefficients of solutes present in the aqueous phase with Bromley equation. $Zn^{2+}\;2Cl^{-}\;+\;R_3NHCl_{org}\;=\;ZnCl_3R_3NH_{org},\;K_{ex}\;=\;6.33\;{\times}\;10^2$ There was a good agreement between measured and calculated distribution coefficients of Zn(II).

• Resources Recycling
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• v.7 no.1
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• pp.7-13
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• 1998

The electric arc furnace (EAF) dust used in this experiment showed the formation of an irregular agglomerate of small spherical particles and consisted of 27.5% Fe, 18% Zn, 4.83% Pb and 10.2% CaO, and it also contained 3.26% Cl and 0.15% F. IR spectra peaks of Pb(OH)Cl were observed at 1630 and 1377 ${cm}^{-1}$ regions and the intensity decreased using an acid treatment (1N ${H}_{2}{SO}_{4}$) and thermal treatment at above 600℃, but it was not affected by washing process. Those of ${Zn}_{5}{(OH)}_{8}{Cl}_{2}$ treated by oxidation showed broad absorption peak at 3600∼3200 ${cm}^{-1}$, main peaks at 1136 and 1040 ${cm}^{-1}$ and a splitting peak at 991 and 921 ${cm}^{-1}$ which were believed to be due to ZnO by oxidation at about 700∼. The IR spectra of the dust residues by a washing process show the same peaks at 3449, 1635, 1439, 875, 571 and 455 ${cm}^{-1}$ regions, but the peaks at 2942, 2862, 1136 and 1040 ${cm}^{-1}$ decreased and disappeared using an acid treatment and washing process, which is believed to be due to the dissolution of zinc hydroxyl chloride.

• Journal of Environmental Health Sciences
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• v.27 no.2
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• pp.82-91
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• 2001

This study was carried out to elucidate the protective effect of zinc chloride(ZnCl$_2$) and its mechanism against the immuno-cytotoxicity of methylmercury chloide($CH_3$HgCl). This study was observed in the culture of EMT-6 cells which are originated from mammary adenocarcinoma of Balb/c mouse. Cytotoxicity of metals was measured by cell viability and NO$_2$$^{[-10]}$ , and mitochondrial function was evaluated by adenosine triphosohate (ATP) production. $CH_3$HgCl significantly decreased the sythesis of nitric oxide(NO), ATP and glutathione(GSH) in a dose-dependent manner. ZnCl$_2$ significantly increased the synthesis of GSH in a dose-dependent manner, but synthesis of NO and ATP were not changed. The immuno-cytotoxicity of $CH_3$HgCl was not fully protected when combined addition of ZnCl$_2$, whereas ZnCl$_2$ prior to addition of $CH_3$HgCl completly protected the Hg-induced immuno-cytotoxicity. Similarly, intracellular accumulation of mercury significantly decreased by ZnCl$_2$. Degree of diminution of intracellular mercury was larger in ZnCl$_2$ prior to addition of $CH_3$HgCl than in combined addition of ZnCl$_2$ and $CH_3$HgCl.. Dithiothreitol(DTT) or buthionine sulfoximine(BSO) addition at 50$\mu$M or less, which was not toxic to the cells, did not affect synthesis of NO and ATP. DTT increased intracellular GSH level and DTT pretreatment protected toxicity induced by $CH_3$HgCl as shown complete recover in the NO and ATP values. BSO decreased intracellular GSH level and BSO pretreatment exaggerated toxicity induced by $CH_3$HgCl as shown synergistic reduction in the NO and ATP values. These results indicated that the protective effects of zinc against immuno-cytotoxicity of methylmercury associated with increasing cellular level of GSH. Increased intracellular GSH transports methylmercury to out of cells. In accordance with intracellular level of mercury decreased, immuno-cytotoxicity of methylmercury decreased. These result also suggest that the protective mechanism of zinc against the mercury toxicity would be exerted in the immune system in vivo.