• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1140-1142
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• 1993

It has been prepared by a coprecipitation method for Ferroxplana $Ni_2Y\;(Ba_2Ni_2Fe_{12}O_{22}$ magnetic particles, which is one of the Hexagonal ferrite. The coprecipitates were synthesized by adding aqueous solution of $BaCl_2{\cdot}2H_2O,\;NiCl_2{\cdot}6H_2O\;and\;FeCl_2{\cdot}4H_2O$ (of which the mole ratio is $Ba^{2+}:Ni^{2+}:Fe^{2+}$=1:1:6) to a mixture of NaOH and $Na_2CO_3$ solution. The shape of Ferroxplana $Ni_2Y$ magnetic particles obtained at the calcined temperature 1,100($^{\circ}C$) was hexagonal plate-like, average particle size was 2(${\mu}m$), and aspect ratio was more than 7.

• Journal of the Korean Chemical Society
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• v.30 no.6
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• pp.526-531
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• 1986

The stability constants of 1,15-diaza-3,4:12,13-dibenzo-5,8,11-trioxacycloheptadecane (NenOdien H$_4$, L) with transition metal ions such as $Co^{2+},\;Ni^{2+},\;Cu^{2+},\;and\;Zn^{2+}$ have been determined by potentiometry in 95% methanol solution at 25$^{\circ}$C. The complex formation of the NenOdien $_4$ with the transition metal ions depends on the basicity of the donor atoms. The order of complex stability was Co(II) < Ni(II) < Cu(II) > Zn(II). The geometries of the complexes in solid state were discussed by visible-near infrared and infrared spectrophotometry, elemental analysis and electro-conductivity. The results suggest that the geometries of the solid complexes are octahedral for $[CoL_2(OH_2)Cl]Cl{\cdot}2H_2O$, $[NiL_2(OH_2)Cl]Cl{\cdot}2H_2O$, and $[ZnLCl_2]{\cdot}\frac{1}{2}H_2O$ and square pyramidal for [CuLCl]Cl, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1993.11a
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• pp.124-127
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• 1993

In this paper, the magnetic properties of Ni-Zn ferrite powders dependent on pH have been studied. Ni-Zn ferrite powders were synthesized by coprecipitation method(pH were 7. 9. 11 and 13. respetively) using FeCl$_3$$.$ 6H$_2$O, NiCl$_2$$.$6H$_2$O and ZnCl$_2$as starting materials and its powders were calcined at 1,000($^{\circ}C$). The saturated magnetizations of the Ni-Zn ferrite powders dependent on various pH. such as 7, 9, 11 and 13 were 11.44, 29.77, 69.62 and 66.75(emu/g), respetively.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.824-829
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• 2002

New di-N-cyanomethylated tetraaza macrocycle 2.13-bis(cyanomethyl)-5.16-dimethyl-2,6,13,17-tetraazatricyclo[$16.4.0.0^7.12$]docosane $(L^2)$ has been prepared by the reaction of 3, 14-dimethyl-2,6,13,17-tetraazatricyclo $(L^1)$ with bromoacetonitrile. The square-planar complexes $[ML^2](ClO_4)_2(M=Ni(II)$ or Cu(II) can be prepared by the reaction of $L^2$ with the corresponding metal ion in acetonitrile. The cyanomethyl groups of $[ML^2](ClO_4)_2readily$ react with water to $yield[ML^3](ClO_4)_2$ containing pendant amide groups. The trans-octahedral complexes $[ML^4](ClO_4)_2$, in which two imidate ester groups are coordinated to the metal ion, can be also prepared by the reaction of $[ML^2](ClO_4)_2with$ methanol under mild conditions. The hydrolysis and alcoholysis reactions of $[ML^2](ClO_4)_2are$ promoted by the central metal ion, in spite of the fact that the cyanomethyl group is not involved in intramolecular coordination. The reactions are also promoted by a base such as triethylamine but are retarded by an $acid(HClO_4).Interestingly$, the imidate ester groups of $[ML^4]^2$ are unusually resistant to hydrolysis even in 0.1 M $HCIO_4$ or 0.1 M NaOH aqueous solution. Crystal structure of $[NiL^4](ClO_4)_2shows$ that the Ni-N (pendant imidate ester group) bond is rlatively strong; the Ni-N bond distance is shorter then the Ni-N(tertiary) distance and is similar to the Ni-N (secondary) distance.

• Journal of the Korean Society for Heat Treatment
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• v.7 no.2
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• pp.129-138
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• 1994

The purpose of this study is to clarify the influence of the reaction temperature and $AlCl_3$ content on the aluminide coating formation on Ni-based superalloy IN713C in CVD process and to compare its throwing power with that of Pack Cementation process. Aluminide coating was formed by CVD in hot-wall stainless tube reactor from an $AlCl_3-H_2$ mixture in the temperature range $850{\sim}1050^{\circ}C$. At reaction temperature $850^{\circ}C$, the coating thickness and the content of aluminium at the surface were increased as $AlCl_3$ heating temperature was raised. At reaction temperature $1050^{\circ}C$, they were not influenced by the variation of $AlCl_3$ heating temperature. When $AlCl_3$ heating temperature was fixed $125^{\circ}C$, the phases of the coatings were varied from $Ni_2Al_3$ to Al-rich NiAl and to Ni-rich NiAl with the reaction temperature. Therefore, in this study the reaction temperature has been found to be a major factor in determining the phase formed in CVD process. The throwing power of CVD was superior to that of Pack Cementation.

• Applied Chemistry for Engineering
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• v.32 no.6
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• pp.671-678
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• 2021

Effects of nitric acid treatment of an activated carbon and impregnation of metal chlorides on the activated carbon were investigated to improve ammonia adsorption performance. It was confirmed that functional groups such as hydroxyl and carboxyl groups were introduced onto a surface of the activated carbon with nitric acid treatment. Then, each metal chloride (NiCl₂, MgCl₂, CuCl₂, MnCl₂ or CoCl₂) was impregnated onto the surface-modified activated carbon using an ultrasonic impregnation method. The physicochemical properties and ammonia adsorption performance of various impregnated activated carbons were observed. Metal chlorides were well dispersed by sonication and evenly distributed on the surface of the activated carbon. Despite the reduced specific surface area and pore volume, the surface-modified activated carbon impregnated with metal chlorides exhibited excellent ammonia adsorption performance. In particular, HNO₃-NiCl₂ AC prepared by impregnating NiCl₂ showed the best ammonia adsorption capacity of 3.736 mmol·g^-1, which was improved by about 57 times compared to that of an untreated activated carbon (0.066 mmol·g^-1).

• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.339-345
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• 2007

Urea reacts with PtCl2, H2[PtCl6]·6H2O, H2[IrCl6] and Ni(CH3CO2)2 in aqueous solution at high temperature (60-80 °C) yielding [PtCl2(Urea)]·2H2O (1), (NH4)2[PtCl6] (2), (NH4)2[IrCl6]·H2O (3) and [Ni2(OH)2(NCO)2(H2O)2] (4) complexes, respectively. In complex 1, urea coordinates to Pt(II) as a neutral bidentate ligand via amido nitrogen atoms. In complexes 2, 3 and 4 it seems that the coordinated urea molecules decompose during the reaction at high temperature and a variety of reaction products are obtained. All complexes were isolated in moderate yields as dark green (1), yellow (2), pale brown (3) and faint green (4) precipitates, respectively. The reaction products were characterized by their microanalysis, IR, 1H and 13C NMR spectra as well as thermal analysis. General mechanisms describing the formation of these complexes were suggested.

• Bulletin of the Korean Chemical Society
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• v.27 no.11
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• pp.1747-1751
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• 2006

The dinuclear tetraazadiphenol macrocyclic nickel(II) complexes [$Ni_2$([20]-DCHDC)]$Cl_2$ (I), [$Ni_2$([20]-DCHDC)]$(ClO_4)_2{\cdot}2CH_3CN $ (II(b)) and [$Ni_2$([20]-DCHDC)$(NCS)_2$] (III) {$H_2$[20]-DCHDC = 14,29-dimethyl-3,10,18,25-tetraazapentacyclo-[25,3,1,$0^{4,9}$,$1^{12,16}$,$0^{19,24}$]ditriacontane-2,10,12,14,16(32),17,27(31), 28,30-decane-31,32-diol} have been synthesized by self-assembly and characterized by elemental analyses, conductances, FT-IR and FAB-MS spectra, and single crystal X-ray diffraction. The crystal structure of II(b) is determined. It crystallizes in the monoclinic space group P2(1)/c. The coordination geometries around Ni(II) ions in I and II(b) are identical and square planes. In complex III each Ni(II) ion is coordinated to $N_2O_2$ plane from the macrocycle and N atoms of NCS- ions occupying the axial positions, forming a square pyramidal geometry. The nonbonded Ni…Ni intermetallic separation in the complex II(b) is 2.8078(10) $\AA$. The FAB mass spectra of I, II and III display major fragments at m/z 635.1, 699.4 and 662.4 corresponding to [$Ni_2$([20]-DCHDC)(Cl + 2H)]$^+$, [$Ni_2$([20]-DCHDC)$(ClO_4\;+\;2H)]^+$ and [$Ni_2$([20]-DCHDC)(NCS) + 6H]$^+$, respectively.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.53-59
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• 2005

The effect of various stressors such as reductant ascorbic acid, signalling molecules (salicylic acid and methyl jasmonic acid), heavy metals $(NiCl_2,\;and\;MnSO_4)$ and NaCl on the glutathione peroxidase (GPX) activities and isoenzyme expression patterns were investigated in rice seedling roots. Total GPX activity increased according to the increase of ascorbic acid concentration. Prominent enhancement of GPX1 isozyme due to ascorbic acid contributed to the increase of total GPX activity. GPX showed different reactivity toward salicylic acid and methyl jasmonic acid. GPX activity increased at 0.1 mM salicylic acid, and then decreased thereafter. However, GPX increased gradually in a methyl jasmonic acid concentration-dependent manner, and 3 fold increase of GPX activity was found at 1 mM methyl jasmonic acid. Moreover, GPX1 isozyme increased according to the increase of salicylic acid, while GPX1 isozyme decreased according to the increase of methyl jasmonic acid. When metal ions were treated, GPX activity increased considerably according to the increase of $NiCl_2$ concentration, however, GPX activity increased about 2 fold at 0.5 mM $CuSO_4$ and then decreased. Enhancement of GPX1 isozyme contributed to the increase of total GPX activities in $NiCl_2-treated$ and $MnSO_4-treated$ rice seedlings. Total GPX activity increased 1.7 fold in response to 300 mM NaCl. Especially GPX2 isozyme showed gradual increase according to the increase of NaCl concentration.

• Journal of Preventive Medicine and Public Health
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• v.34 no.2
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• pp.127-130
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• 2001

Objective : To verify the separate and combined effects of cadmium and nickel on blood pressure in rats. Methods : Following the daily administration of cadmium chloride$(CdCl_2)$ and nickel chloride$(NiCl_2)$ to rats both individually and in combination with intraperitoneal injection method for one week, systolic blood pressure of the tail was measured at 1 day and 5, 10, 20, 30 days after administration. Each substance was injected into the rats with 0.1 mg/kg bw and 1.0 mg/kg bw concentration. Results : After 0.1 mg/kg bw $CdCl_2$ was injected, a statistically significant difference was found as compared with the control group(only saline) after 1, 5 and 10 days. After 0.1 mg/kg bw $NiCl_2$ was injected, a statistically significant difference was not found compared with the control group. After 0.1 mg/kg bw $CdCl_2$ and 0.1 mg/kg bw $NiCl_2$ were injected simultaneously, a statistically significant difference was found as compared with the control group after 1,5 and 10 days and compared with 0.1 mg/kg bw $CdCl_2$ group after 5 days and as compared with 0.1 mg/kg bw $NiCl_2$ group after 5 and 10 days. After 1.0 mg/kg bw $CdCl_2$ was injected, a statistically significant difference was found as compared with the control group after 1, 5, 10 and 20 days. After 1.0 mg/kg bw $NiCl_2$ was injected, a statistically significant difference was found as compared with the control group after 1 day and 5 days. After 1.0 mg/kg bw $CdCl_2$ and 1.0 mg/kg bw $NiCl_2$ were injected in combination, a statistically significant difference was found after 1, 5, 10, 20 and 30 days as compared with 1.0 mg/kg bw $CdCl_2$ after 10, 20 and 30 days and as compared with 1.0 mg/kg bw $NiCl_2$ after 5, 10, 20 and 30 days. Conclusion : It was found that the effect of $CdCl_2$ on blood pressure was much more than $NiCl_2$ and a high concentration $CdCl_2\;and\;NiCl_2$ in combination delayed the recovery of blood pressure.