• Title/Summary/Keyword: Ions

Search Result 7,054, Processing Time 0.039 seconds

A study on the removal of mixed heavy metal ions using crab shell (게 껍질을 이용한 수중의 복합 중금속 제거에 관한 연구)

  • Kim, Dong-Seog
    • Journal of Environmental Science International
    • /
    • v.11 no.7
    • /
    • pp.729-735
    • /
    • 2002
  • In order to examine the inhibition effect of other heavy metal ions on the removal of heavy metal ions by crab shell in aqueous solution, 10 heavy metal ions $(Cr^{3+},\;Cd^{2+},\;Ni^{2+},\;Zn^{2+},\;Hg^{2+},\;Cu^{2+},\;Mn^{2+],\;Fe^{2+},\;Fe^{3+},\;Pb^{2+})$ were used as single heavy metal ions and mixed heavy metal ions, respectively. In single heavy metal ions, $Pb^{2+},\;Cr^{3+},\;Cu^{2+}$ were well removed by crab shell, however, $Cd^{2+},\;Ni^{2+},\;Zn^{2+},\;Mn^{2+}$ were not. The heavy metal removal increased as the increase of covalent index (Xm$^2$r), and the relationship classified heavy metal ions as 2 heavy metal groups $(Fe^{3+},\;Fe^{2+},\;Cu^{2+},\; Cr^{3+},\;Mn^{2+},\;Ni^{2+},\;Zn^{2+}\;group\;and\;Pb^{2+},\;Hg^{2+},\;Cd^{2+}\;group)$. In mixed heavy metal ions, the removals of $Fe^{2+},\;Fe^{3+},\;Pb^{2+},\;Cu^{2+}$ as 0.49 m㏖/g, regardless of the existence of other heavy metal ions, were similar to the result of single heavy metal ions experiment. The removals of $Mn^{2+},\;Cd^{2+},\;Ni^{2+}$ decreased as the existence of other heavy metal ions, however, the removal of $Zn^{2+},\;Cr^{3+},\;Hg^{2+}$ increased.

Solidification of Heavy Metal Ions Using Magnesia-phosphate Cement (인산염 마그네시아 시멘트에 의한 중금속 이온 고정화)

  • Choi, Hun;Kang, Hyun-Ju;Song, Myung-Shin;Jung, Eui-Dam;Kim, Ju-Seng
    • Journal of the Korean Ceramic Society
    • /
    • v.48 no.1
    • /
    • pp.20-25
    • /
    • 2011
  • Since 1980's, many mines have been closed and abandoned due to the exhaustion of deposits and declining prices of international mineral resources. Because of the lack of post management for these abandoned mines, Farm land and rivers were contaminated with heavy metal ions and sludge. We studied on the solidification/stabilization of heavy metal ions, chromium ions and lead ions, using magnesia-phosphate cement. Magnesia binders were used calcined-magnesia and dead-burned magnesia. Test specimens were prepared by mixing magnesia binder with chromium ions and lead ions and activators. We analyzed the hydrates by reaction between magnesiaphosphate cement and each heavy metal ions by XRD and SEM-EDAX, and analyzed the content of heavy metal ions in the eruption water from the specimens for the solidification and stabilization of heavy metal ions by ICP. The results was shown that calcined magnesia binder is effective in stabilization for chromium ions and dead-burned magnesia binder is effective in stabilization for lead ions.

Effect of antibacterial activity on the elution of silver ions from A-type zeolite supporting silver ions (은이온 교환 A형 제오라이트로 부터의 은이온용출이 항균력에 미치는 영향)

  • Lee, Mu Gang;Sin, Hyeon Mu;Im, Gyeong Cheon
    • Journal of Environmental Science International
    • /
    • v.13 no.1
    • /
    • pp.89-97
    • /
    • 2004
  • An author has been known that A-type zeolite supported with silver ions has excellent antibacterial activity. However, it is no research of concern in the antibacterial activity of eluted silver ions. This study tested the elution of silver ions from A-type zeolite silver ions in deionized distilled water and NaNO$_3$ aqueous solution. In NaNO$_3$ aqueous solution of 74mM to 588mM, it was found that the concentration of silver ions and electric conductivity increased with the increasing concentration of sodium ions, and equilibrated at 15 min, and the ion exchange equilibrium coefficient, k, is 1.3${\times}$10$\^$-3/. However, deionized distilled water is not equilibrated to pass 6 months. A-type zeolite sodium ions showed no antibacterial activity. It was found that antibacterial activity was exhibited even at the concentration of 10 nM of eluted silver ions, and E-coli died with the incorporation of 2.43${\times}$10$\^$8/ Ag ion/cell. antibacterial activity of A-type zeolite silver ions were mainly attributed to hydroxyl radical.

Influence of NiO, $TiO_2$ on ZnO-$SnO_2$ System Spinel Pigment (ZnO-$SnO_2$계 Spinel 채료에 대한 NiO, $TiO_2$의 영향)

  • 이응상;황성윤
    • Journal of the Korean Ceramic Society
    • /
    • v.14 no.3
    • /
    • pp.187-192
    • /
    • 1977
  • For the purpose researching to the influence of tetrahedral and octahedral preference of cations of $Ni^{2+}$, $Ti^{4+}$ upon the formation and the color development of the $ZnO-SnO_2$ spinel containing $Ni^{2+}$ and $Ti^{4+}$ ions, the gradual substitution of $Ni^{2+}$ ions for $Zn^{2+}$ ions and of $Ti^{4+}$ ions for $Sn^{4+}$ ions of the spinel in NiO-ZnO-$SnO_2$-$TiO_2$ system was carried out. On samples prepared by calcining the oxide and basic cabonate mixtures at $1300^{\circ}C$ for 2 hours, the X-ray analysis, measurement of reflectance and the test of their stabilaity as a glaze pigment were also carried out. The results are summarized as follows 1) Single spinel was formed completely to x=1 in the $xNiO\cdot(2-x)ZnO\cdot{SnO}_2$system, and gave brilliant lightgreen hue. Moreover, $NiO\cdot{ZnO}\cdot{SnO}_2$ formed easily spinel than $NiO\cdot{MgO}\cdot{SnO}_2$ because Zn^{2+}$ ions had more strong tetrahedral preference than $Mg^{2+}$ ions. 2) As the gradual substitution of $Ti^{4+}$ ions for $Sn^{4+}$ ions in $NiO\cdot{MgO}\cdot{SnO}_2$ system, the spinels formed well and was nearly not changed in the hue. 3) The results of glaze test. (1) As the gradual substitution of $Ni^{2+}$ ions for $Zn^{2+}$ ions, the color changed from dull white to graish broun gradually in calcium-zinc glaze and calcium glaze, and from white to beige in tile glaze. (2) As the gradual substitution of $Ti^{4+}$ ions for $Sn^{4+}$ ions in $NiO-ZnO-SnO_2-TiO_2$ system, the color was become dull generally and was not change in tile glaze.

  • PDF

Mechanism of Removal of Cr(VI) Ions from Solution by Borosilicate Glasses Containing Alkaline Earth Oxides (알칼리토 금속산화물이 함유된 붕규산염계 유리를 이용한 용액 중 Cr6+ 이온 제거 기구)

  • Back, Il-Hee;Lim, Hyung-Bong;Kim, Cheol-Young
    • Journal of the Korean Ceramic Society
    • /
    • v.48 no.3
    • /
    • pp.222-227
    • /
    • 2011
  • The hexavalent chromium ions in wastewater are highly toxic chemicals even at low concentrations. It causes serious diseases, such as cancer, skin disease, digestive trouble et. al. In this study, $Cr^{6+}$ ions were removed by using borosilicate glasses. Various glasses system with different compositions were prepared and then reacted in a solution contaning $Cr^{6+}$ ions. After the reaction, the concentration of the $Cr^{6+}$ ions remained in the solution was measured by ICP-OES. The reacted surface of the glasses was also analyzed by using a XRD, SEM, and EDS. When $Na_2O-RO-SiO_2-B_2O_3$ (RO=MgO, CaO, SrO, BaO) glasses were reacted with a solution containing $Cr^{6+}$ ions, the optimum removal efficiency of $Cr^{6+}$ ions was observed in the BaO glass. $Ba^{2+}$ ions leached out of these glasses combine with $Cr^{6+}$ ions in a solution to form $BaCrO_4$ crystals on the glass surface. In this manner, the $Cr^{6+}$ ions can be removed from the solution. It is conceivable that $Ba^{2+}$ ions are reacted with $Cr^{6+}$ ions in a solution immedeately after leaching out of the glasses. The pH of the solution for optimum removal of $Cr^{6+}$ ions were 3.0~5.0.

Statistical Characterization of the Multi-Charged Fragment Ions in the CID and HCD Spectrum

  • Ramachandran, Sangeetha;Thomas, Tessamma
    • Mass Spectrometry Letters
    • /
    • v.12 no.2
    • /
    • pp.41-46
    • /
    • 2021
  • Collision-induced dissociation (CID) and higher-energy collisional dissociation (HCD) are the widely used fragmentation technique in mass spectrometry-based proteomics studies. Understanding the fragmentation pattern from the tandem mass spectra using statistical methods helps to implement efficient spectrum analysis algorithms. The study characterizes the frequency of occurrence of multi-charged fragment ions and their neutral loss events of doubly and triply charged peptides in the CID and HCD spectrum. The dependency of the length of the fragment ion on the occurrence of multi-charged fragment ion is characterized here. Study shows that the singly charged fragment ions are generally dominated in the doubly charged peptide spectrum. However, as the length of the product ion increases, the frequency of occurrence of charge 2 fragment ions increases. The y- ions have more tendencies to generate charge 2 fragment ions than b- ions, both in CID and HCD spectrum. The frequency of occurrence of charge 2 fragment ion peaks is prominent upon the dissociation of the triply charged peptides. For triply charged peptides, product ion of higher length occurred in multiple charge states in CID spectrum. The neutral loss peaks mostly exist in charge 2 states in the triply charged peptide spectrum. The b-ions peaks are observed in much less frequency than y-ions in HCD spectrum as the length of the fragment increases. Isotopic peaks are occurred in charge 2 state both in doubly and triply charged peptide's HCD spectrum.

Studies of Element Substitution on Superconductivity in Bi-Sr-Ca-Cu-O Oxides (Bi계 치환 고온 초전도체)

  • 권오흥;박천제
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • 2000.11a
    • /
    • pp.124-128
    • /
    • 2000
  • The high Tc phase disappeared and low Tc phase increased in the substitution of transistion elements for Bi ions. The high Tc phase decreased in the substitution of Si and Sn for Bi ions. The high Tc phase increased in the substitution of Sb, As and P Which Were the same group of Bi for Bi ions. The substitution of P ions was the most effective and then the high Tc phase was formed in large quantity by replacing Bi ions with 30%of P ions.

  • PDF

First-Principles Study of Magnetic Interactions between Transition Metal Ions in ZnO (ZnO내 전이 금속 불순물의 자기적 특성에 관한 제일원리 연구)

  • Lee, Eun-Cheol
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.23 no.6
    • /
    • pp.444-448
    • /
    • 2010
  • Based on first-principles calculations, we study the magnetic properties of Co, Ni, Fe, V, and Mn impurities in ZnO. The stabilities of the ferromagnetic state and the magnetic moment of each impurity largely depend on the amount of doped electron or hole. For lightly doped n-type ZnO, it is found that the doping of Ni ions is the most effective for inducing ferromagnetism, while Fe ions show the most stable ferromagnetic couplings for heavily doped n-type samples. The characteristics of the magnetic interactions of Co ions are similar with those of Fe ions, but Co ions require much larger amount of doped electron than Fe ions to show the ferromagnetic couplings. The ferromagnetic coupling between Mn and V ions is unstable in n-type conditions.

Effect of Metal Ions on Speroxide Dismutase of the Liver in Senescence-Accelerated Mouse(SAM) (노화촉진생쥐(SAM)의 간에서 금속이온이 SOD의 활성에 미치는 영향)

  • 양미경;박문숙
    • Journal of environmental and Sanitary engineering
    • /
    • v.15 no.2
    • /
    • pp.1-9
    • /
    • 2000
  • This research employed a senescence-accelerated mouse(SAM) to explore the possibility that differences exits among the major antioxidants, superoxid dismutase(SOD), in terms of ability to protect such animal treated with Cu, Fe and Mn. To assess the antioxidants function of metal ions on SAM-R/1 and SAM-P/8 were administered with Cu, Fe and Mn orally. The effect of metal ions on SAM towards reversing oxygen sensitivity was determined as a bioassays of SOD in the mouse liver. The data show that the SOD activity was induced by each metal ions in both SAM-R/1 and SAM-P/8. It suggested that induced SOD by each metal ions may protect against oxidative mediated stress. Finally, overall data lead to the possibility of metal ions as an antioxidants or each metal ions act producer of oxygen radicals in the liver of SAM-R/1 and SAM-P/8.

  • PDF

Adsorption Characteristics of Nickel, Zinc and Cadmium Ions using Alginate Bead (Alginate Bead를 이용한 니켈, 아연, 카드뮴의 흡착특성에 관한 연구)

  • Jung, Heung-Joe
    • Journal of Integrative Natural Science
    • /
    • v.4 no.2
    • /
    • pp.130-136
    • /
    • 2011
  • This study investigated the adsorption characteristics of nickel, zinc and cadmium ions from the aqueous solution onto the alginate bead. Adsorption equilibrium capacities of the heavy metal ions increased with increasing initial pH of the solution. The adsorption equilibrium isotherm of the heavy metal ions was well represented by Langmuir equation. The magnitude of adsorption capacity of the heavy metal ions onto alginate bead was the order of cadmium > zinc > nickel. Kinetic parameters were measured in a batch adsorber to analyze the adsorption rates of the heavy metal ions. The internal diffusion coefficient of the heavy metal ions in the intraparticle were determined by comparing the experimental concentration curves with those predicted from the surface diffusion model (SDM) and pore diffusion model (PDM). The internal diffusion of the heavy metal ions in the intraparticles was explained by PDM.