• 대한화학회지
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• 제36권4호
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• pp.546-551
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• 1992

니켈(Ⅱ)이온을 N-benzylisonitrosoacetylacetone imine(HIAANB)으로 용매추출할 때의 반응메카니즘을 분광광도법으로 연구하였다. 유기상 chloroform에 녹아있는 리간드 HIAANB농도와 수용액층의 pH값을 변화시켜 가면서 흡광도를 측정하였다. 측정 데이터로부터 반응속도가 HIAANB농도에 대하여는 1차, [$H^+$]에 대하여는 -1차임을 알 수 있었다. 추출반응의 속도결정단계와 속도식은 다음과 같다. $Ni^{2+}$＋HIAANB ${\to}$ Ni-IAANB$^+$＋$H^+$ -d[Ni$^{2+}$] / dt = K'[Ni$^{2+}$][HIAANB]$_0$ / [H$^+$]. 수용액 중의 니켈(Ⅱ)이온을 분광광도법으로 정량할 때의 검정곡선은 최적실험조건에서 1.17ppm 이하의 농도범위에서 직선이었다. 또 리간드 대 금속의 결합비, 추출율과 수용액상의 pH 사이의 관계, 니켈(Ⅱ)이온을 정량할 때의 방해이온의 영향도 조사하였다.

• 대한치과보철학회지
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• 제37권6호
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• pp.717-729
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• 1999

Although many studies on the cytotoxicity of the dental cast base metal alloys and their components have been carried out, the results are rather conflicting because of the different type of cells used and the various experimental procedures taken. Recently a number of scientists have claimed that it would be preferable to focus on the use of cells from relevant specific location of the human bodies. Consequently, the primary cultured oral keratinocyte derived from oral mucous along with nickel chloride and several of widely used dental cast base metal alloys(two Ni-Cr alloys and one Co-Cr alloy)in domestic were selected for this study, from which 1) The amounts of released metal ions were determined using atomic absorption spectrometry, 2) The cytotoxicity of nickel chloride and dental cast base metal alloys was evaluated via MTT assay, and finally, 3) The amounts of released metal ions and the cytotoxicity of nickel chloride were correlated with the cytotoxicity of dental cast base metal alloys And, the results were summarized as follows; 1. Nickel ion from Ni-Cr alloys and Cobalt ion from Co-Cr alloys resulted in maximum releasing rate during first 2h hours, followed by a decrease in releasing rate with time. Chromium ion were found to be minimal in all alloys. 2. In cytotoxic test. with $40{\mu}M,\;80{\mu}M$ of nickel chloride, there were observed an increase in the relative cell number compared to control samples after 24 hours. With $160{\mu}M$, there was found to be no difference in the relative cell number with control, except that 48 hour showed a increase in relative cell number. With $320{\mu}M$, the relative cell number remained constant and decreased after 48 hours, and with $640{\mu}M$, a continuing decrease in relative cell number was observed throughout test period. 3 The sensitivity of primary cultured oral epithelium to nickel was lower compared to the cells used in other studies. 4. CB-80 Soft and Regalloy showed no cytotoxicity to primary cultured oral epithelium and New crown resulted in a slight cytotoxicity. In conclusion, it was shown that the primary cultured oral keratinocytes could be applied successfully as testing cells in cytotoxicity test. Futhermore, the dental cast base metal alloys used in this study were found to be biocompatible.

• 한국진공학회지
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• 제3권1호
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• pp.130-137
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• 1994

SbSBr, BiSBr, SbSBr : Co, BiSBr : Co, SbSBr : Ni 및 BiSBr : Ni 단결정을 수직 Bridgman 방법으로 성장시켰다. 성장된 단결정의 구조는 orthorhombic 구조이며 광학적 energy band gap 구조는 간접적이형이었고 energy gap의 온도의존성은 일차 및 이차 상전이점에서 anomalous 한 특성이 나 타 났다. 불순물로 첨가한 cobalt와 nickel은 Td 대칭점에 Co2+ ion, Co3+ ion 및 Ni2+ ion으로 위치하며 이들 ion의 energy 준위간의 전자전이에 의하여 불순물 광흡수 peak들이 나타난다.

• Bulletin of the Korean Chemical Society
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• 제19권7호
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• pp.784-786
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• 1998

• 한국표면공학회지
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• 제20권1호
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• pp.4-14
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• 1987

The nickel-zinc alloy depositions have been studied in nickel chloride added chloride baths, to find out the effects of ultrasonic irradiation for the electrodeposition processes. The compositions of deposited alloys, the current efficiencies and the metallographic appearances in various conditions of Electrodeposition were investigated, in the range of ultrasonic irradiation of 50,500 and 1,000 Kc/s respectively. The results obtained are as follows; 1. Generally the nickel deposition process is more preferably activated than that of zinc by the ultrasonic irradiation. 2. The radios of nickel to zinc in the deposit are higher according to increase of nickel ion concentration and bath temperatures in irradiated baths. 3. The current efficiencies are also higher in the irradiated baths, so that the depolarization effect is noticeable. 4. The brightness and leveling effect of the deposits are appreciably better in the irradiated baths than in non-irradiated in 0.3M and 0.6M of nickel chloride and zinc chloride solutions and the current density of 3A/$dm^2$. 5. The mechanism of alloy deposition has been tentatively suggested in the case of ultrasonic irradiation.

• 자원리싸이클링
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• 제27권4호
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• pp.36-43
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• 2018

폐 니켈-카드뮴 전지의 재활용을 위하여 효율적으로 카드뮴과 니켈을 분리할 수 있도록 이온치환 반응을 이용하여 선택적으로 카드뮴을 분리하였다. 폐 니켈-카드뮴 전지 내의 전극을 분쇄하여 얻은 전극 분말을 황산에 침출시킨 니켈-카드뮴 용액에 황화나트륨을 첨가하여 CdS로 침전시켰다. 다양한 조건에서 이온치환실험을 실시하였으며, 최적조건으로는 상온에서 용액의 pH = -0.1, $Na_2S/Cd=2.3$일 때 용액 내 잔존하는 Cd은 약 100 ppm으로 대부분 CdS로 침전된 결과를 얻을 수 있었다.

• 한국표면공학회지
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• 제57권2호
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• pp.57-70
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• 2024

Nickel-cobalt-manganese (NCM) lithium-ion batteries(LIBs) are increasingly prominent in the energy storage system due to their high energy density and cost-effectiveness. However, they face significant challenges, such as rapid capacity fading and structural instability during high-voltage operation cycles. Addressing these issues, numerous researchers have studied the enhancement of electrochemical performance through the coating of NCM cathode materials with substances like metal oxides, lithium composites, and polymers. Coating these cathode materials serves several critical functions: it acts as a protection barrier against electrolyte decomposition, mitigates the dissolution of transition metals, enhances the structural integrity of the electrode, and can even improve the ionic conductivity of the cathode. Ultimately, these improvements lead to better cycle stability, increased efficiency, and enhanced overall battery life, which are crucial for the advancement of NCM-based lithium-ion batteries in high-demand applications. So, this paper will review various cathode coating materials and examine the roles each plays in improving battery performance.

• 통합자연과학논문집
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• 제4권2호
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• pp.130-136
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• 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.

• Bulletin of the Korean Chemical Society
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• 제25권1호
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• pp.37-41
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• 2004

A new tridentate ligand incorporating a monoxime and thiosemi-carbozone moieties has been synthesized. Its copper(II), nickel(II) and palladium(II) complexes have been prepared and characteirzed by physical and spectral methods. Elemental analyses and spectroscopic data of the metal complexes are consistent with the formation of a mononuclear copper(II) complex and binuclear complex with both nickel(II) and palladium(II). In the copper(II) complex the fourth coordination site is occupied by nitrate ion. In the binculear complexes the fourth coordination site is occupied by the deprotonated oxime oxygen of the ligand coordinated to the other metal.

• 한국표면공학회지
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• 제38권4호
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• pp.156-162
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• 2005

Nickel-iron nanocrystalline alloys with different compositions and grain sizes were fabricated by electro-plating for MEMS devices. The iron content of the deposits was changed by varying the nickel/iron ion ratio in the electrolyte. X-ray diffraction (XRD) analysis was applied for measuring the strength of the texture and grain size of the deposits. The nickel/iron atom ratio of the deposits was analyzed by EDS. The hardness of the alloys was evaluated by Vickers hardness indenter. The internal stress of the deposits was measured by Thin Film Stress Measurement using Stoney's formula. Surface morphology and roughness were investigated by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The results of this study revealed that at a grain size of approximately $17\~24$nm the hardness, internal stress and roughness depend strongly on the iron content. With increasing the iron content, the hardness and internal stress of the deposits increased. An excellent correlation between the increase in the internal stress and the loss of (200) texture was found.