• Journal of the Korean Chemical Society
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• v.54 no.3
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• pp.269-274
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• 2010

The solubility and the physicochemical property (refractive index) in the NaCl-$CaCl_2$-$H_2O$ and KCl-$CaCl_2$-$H_2O$ systems were determined at $50^{\circ}C$ and the phase diagrams and the diagrams of physicochemical property vs composition were plotted. One invariant point, two univariant curves, and two crystallization zones, corresponding to sodium Chloride (or potassium chloride), dihydrate ($CaCl_2{\cdot}2H_2O$) showed up in the phase diagrams of the ternary systems. The mixing parameters ${\theta}_{M,Ca}$ and ${\Psi}_{M,Ca,Cl}$ (M = Na or K) and equilibrium constant $K_{sp}$ were evaluated in NaCl-$CaCl_2-H_2O$ and KCl-$CaCl_2-H_2O$ systems by least-squares optimization procedure, in which the single-salt Pitzer parameters of NaCl, KCl and $CaCl_2$ ${\beta}^{(0)}$, ${\beta}^{(1)}$, ${\beta}^{(2)}$ and $C^{\Phi}$ were directly calculated from the literature. The results obtained were in good agreement with the experimental data.

• Journal of Positioning, Navigation, and Timing
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• v.4 no.4
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• pp.151-160
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• 2015

GPS L2C signal is a recently added civil signal to L2 frequency and is constructed by time division multiplexing of civil moderate (L2-CM) and civil long (L2-CL) code signals. While the L2-CM code is 20 ms-periodic and modulates satellite navigation message, the L2-CL code is 1.5s-periodic with 767,250 chips long code sequence and carries no data. Therefore, the L2-CL code signal allows receivers to perform a very long coherent integration. However, due to the length of the L2-CL code, the acquisition of the L2-CL code signal may take too long or require too much hardware resources. In this paper, we propose a three-step ultra-fast L2-CL code acquisition (TSCLA) technique for dual band GPS receivers. In the proposed TSCLA technique, a dual band GPS receiver sequentially acquires the coarse/acquisition (C/A) code signal at L1 frequency, the L2-CM code signal, and the L2-CL code signal to minimize mean acquisition time (MAT). The theoretical performance analysis and numerous Monte Carlo simulations show the significant advantage of the proposed TSCLA technique over conventional techniques introduced in the literature.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.3
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• pp.415-420
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• 2020

Strontium is known as a salt-soluble element during the electrolytic oxide reduction (EOR) process. The chemical behavior of SrO during EOR was investigated via thermodynamic calculations to provide quantitative data on the chemical status of Sr. To achieve this, thermodynamic calculations were conducted using HSC chemistry software for various EOR conditions. It was revealed that SrO reacts with LiCl salt to produce SrCl₂, even in the presence of Li₂O, and that the ratio of SrCl₂ depends on the initial concentration of Li₂O dissolved in LiCl. It was found that SrO reacts with Li to produce Sr during EOR and that the reduced Sr reacts with LiCl salt to produce SrCl₂. As a result, the proportions of metallic forms were lower in Sr than in La and Nd under various EOR conditions. The thermodynamic calculations indicated that the three chemical forms of SrO, SrCl₂, and Sr co-exist in the EOR system under an equilibrium with Li, Li₂O, and LiCl.

• Preventive Nutrition and Food Science
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• v.12 no.4
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• pp.284-288
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• 2007

Effect of aqueous chlorine dioxide $(ClO_2)$ treatment on the quality change of fresh ginseng during storage was examined. Fresh ginseng samples were treated with 0, 50, and 100 ppm of $ClO_2$ solution, respectively, and stored at $4^{\circ}C$. Microbiological data of the fresh ginseng after $ClO_2$ treatment revealed that the populations of total aerobic bacteria, and yeast and mold were significantly reduced with the increase of $ClO_2$ concentration. In particular, the populations of total aerobic bacteria, and yeast and mold in the fresh ginseng decreased by 2.1 and 1.2 log CFU/g at 100 ppm $ClO_2$ treatment, respectively. Aqueous $ClO_2$ treatment improved the color of the fresh ginseng during storage, but there was no significant difference in weight loss during storage among treatments. Sensory evaluation results represented that the qualities of the fresh ginseng treated with aqueous $ClO_2$ during storage were better than those of the control. These results clearly indicate that aqueous $ClO_2$ treatment could be useful in decreasing the microbial growth and extending the shelf life of fresh ginseng.

• Bulletin of the Korean Chemical Society
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• v.21 no.1
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• pp.65-68
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• 2000

A $\mu-oxo$ diiron(III) complex and two bis( $\mu-alkoxo)$ diiron(III) complexes with biomimetic tripodal ligand containing mixed N/O donor atoms were synthesized using a mononuclear iron(III) complex as starting material. Depending on the amounts and kinds of bases used, we obtained various kinds of diiron (III) complexes. The reaction of $[$Fe^{III}$(Hbbea)Cl_2]Cl$, 1, with an equivalent amount of $KO_2$ or NaOAc produced $[$Fe^{III}$_2O(Hb-bea)_2Cl_2]Cl_2$, 2. An additional equivalent amount of NaOBz or NaOAc converts complex 2 to complex 3 or complex 4 depending on the base used. The addition of two equivalent amounts of NaOBz orNaOAc directly converts complex 1 to $[$Fe^{III}$_2(bbea)_2(OBz)_2]Cl_2$, 3, or $[$Fe^{III}$_2(bbea)_2(OAc)_2]Cl_2$, 4, depending on the base used. Crystal data are as follows: [$Fe^{III}_2O(Hbbea)_2Cl_2]Cl_2$, 2: monoclinic space group $$P2_1/n$$, a = 8.421 (1) $\AA$, b = 18.416 (2) $\AA$, c = 13.736 (1) $\AA$, $\beta$ = 104.870 $(7)^{\circ}$, V = 2058.9 (4) $\AA^3$, Z = 2, R1 = 0.0469 and wR2 = 0.1201 for reflections with I > 2 ${\sigma}$(I).

• Nuclear Engineering and Technology
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• v.47 no.7
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• pp.867-874
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• 2015

Separation of cesium chloride (CsCl) and strontium chloride ($SrCl_2$) from the lithium chloride-potassium chloride (LiCl-KCl) salt was studied using a melt crystallization process similar to the reverse vertical Bridgeman growth technique. A ternary $SrCl_2-LiCl-KCl$ salt was explored at similar growth rates (1.8-5 mm/h) and compared with CsCl ternary results to identify similarities. Quaternary experiments were also conducted and compared with the ternary cases to identify trends and possible limitations to the separations process. In the ternary case, as much as 68% of the total salt could be recycled per batch process. In the quaternary experiments, separation of Cs and Sr was nearly identical at the slower rates; however, as the growth rate increased, $SrCl_2$ separated more easily than CsCl. The quaternary results show less separation and rate dependence than in both ternary cases. As an estimated result, only 51% of the total salt could be recycled per batch. Furthermore, two models have been explored to further understand the growth process and separation. A comparison of the experimental and modeling results reveals that the nonmixed model fits reasonably well with the ternary and quaternary data sets. A dimensional analysis was performed and a correlation was identified to semipredict the segregation coefficient.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.4
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• pp.135-139
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• 2004

The layered organic-inorganic hybrid compounds($C_6H_5CH_2NH_3)_2CuCl_4$ and ($NH_3C_6/H_4C_2H_4_6/H_4NH_3)CuCl_4$ have been directly synthesized. From the X-ray diffraction data and the organic guest size, the orientation of the intercalated organic amine was determined. The inorganic sheets consist of $CuCl_4^{2-}$layers of comer-sharing octahedra copper chloride. The protonated organic amine was intercalated into the $CuCl_4^{2-}$layers with bilayer structure for ($C_6H_5CH_2NH_3)_2CuCl_4$ and monolayer structure for ($NH_3C_6/H_4C_2H_4_6/H_4NH_3)CuCl_4$.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.475-479
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• 1987

This survey was conducted to Investigate the NaCl contents of meals taken from common restaurants in Seoul area and further to estimate the total dietary intake of salt from the meals. The samples included Seoleung-tang (beef and rice soup)/Galbitang (beef-rib soup), Yeukkye-jang (spicy beef soup), Doenjangchigye-bab (boiled rice with soy paste stew), Bibim-bab (boiled rice with assorted mixtures) and Bibim-naengmyon (buck wheat vermicelli with assorted mixtures). The average content of NaCl for each sample was determined by saltmeter and its daily intake level was estimated. Doenjangchigye-bab was shown the highest concentration of NaCl Doen-jangchigye-bab was separated into drained residue and fluid, and the average NaCl content in the fluid was higher than that in the residue. In comparision of northern and southern region of Seoul divided by Han river, there was no significant difference in the content of NaCl. The average content of NaCl per meal was 10.6g, and from these data, the daily dietary intake of salt for adults was estimated to be 28.5g.

• Resources Recycling
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• v.18 no.1
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• pp.30-37
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• 2009

Distribution diagram of Pt(IV), Pd(II), and Rh(III) in HCl solution was obtained as a function of HCl concentration from 0.001 to 10 M by considering complex formation reaction together with mass balance. When HCl concentration was higher than 0.1 M, most of Pt and Pd in HCl solution exist as $PtCl_6^{2-}$ and $PtCl_4^{2-}$. The concentration of HCl had a feat effect on the speciation of Rh(III). As HCl concentration increases from 0.1 to 10 M, the pedominant species changes from $PhCl_5^{2-}$ to $PhCl_6^{3-}$. Interaction parameters of $PtCl_6^{2-}$ and $PdCl_4^{2-}$ with hydrogen ion were evaluated from the solvent extraction data of Pt and Pd reported in the literature.

• Journal of the Korean Chemical Society
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• v.18 no.5
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• pp.358-362
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• 1974

The anion exchange separation of a number of benzoic acid and its derivatives has been studied in various concentrations of $NiCl_2-methanol$ solvent medium. The volume distribution coefficients with Amberlite CG-400, $Cl^-$form have been measured in these medium. Several synthetic mixtures of organic acids were separated quantitatively by elution with a suitable concentration of $NiCl_2-MeOH$ solution suggested by the distribution data. The concentration of organic acids were determined by UV spectrophotometry.