• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.231-231
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• 2009

In this work, we prepared the Ni-loaded porous SBA-15 (SBA-15) by a depositionprecipitation (D-P) method, in order to enhance the hydrogen storage capacity. The structure and morphology of the Ni/SBA-15 were characterized by X-ray diffraction (XRD) and field emission transmission electron microscopy (FE-TEM). The results showed that, at the Ni loading used at the DP times in the range of 0-120 min, SBA-15 preserved the well-ordered hexagonal porous arrangement. The textural properties of the Ni/SBA-15 were analyzed using N2 adsorption isotherms at 77 K. Specific surface area and mesopore volume of the samples were determined from the Brunauer-Emmett-Teller (BET) equation and Barrett-Joiner-Halenda (BJH) method, respectively. The hydrogen storage capacity of the Ni/SBA-15 was evaluated at 298 K/10 MPa. The hydrogen storage capacity of the Ni/SBA-15 was increased in accordance with Ni content. Consequently, it was found that the presence of Ni on mesoporous SBA-15 created hydrogen-favorable sites which enhanced the hydrogen storage capacity by spillover effect.

• Journal of Surface Science and Engineering
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• v.32 no.6
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• pp.703-708
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• 1999

Silicides have been used extensively in ULSI logic device fabrication as contact materials for the active areas as well as the poly- Si gates. NiSi is a promising candidate for submicron device application due to less volume expansion, low formation temperature, little silicon consumption, and large stable processing temperature window. In this report, the microstructure of nickel silicides fabricated with a thermal evaporator has been investigated. We observed systematic transformation of Ni silicides of $Ni_2$Si, NiSi, $NiSi_2$, as annealing temperature increases. All the silicides have been identified by a X-ray diffractometer (XRD). The cross-sectional microstructure of silicides was examined by a transmission electron microscope (TEM) equipped with a energy dispersive spectrometer(EDS). The surface roughness of silicides was measured by scanning probe microscope(SPM). Although we observed thin oxide layer existed at the $Ni/NiSi_{x}$ interface, we fabricated successfully $550\AA$-thick planar Ni-monosilicide at the temperature range of$ 400~700^{\circ}C$.

• 연구논문집
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• s.33
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• pp.183-190
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• 2003

Today, We have used many electronic equipment such as computer, TV, cellular phone and so on. These equipment radiate a large amount of EMI(Electromagnetic interference) which is occurred trouble of airplane, medical equipment, communicate equipment, and especially, human health. So, Ni mesh fabrication for EMI shielding by continuous electroforming process was investigated. Continuous electroforming apparatus was made by means of rotating cathode drum. And We investigated the characteristics of two types of Ni electroforming solution. One was made by laboratory and the other was produced by M cooperation. The grain size increased with increasing current density and bath temperature, and decreasing rotating speed of cathode drum. EDX results indicate that the Ni mesh electroformed by the KIMM solution is composed of pure Ni. But the Ni mesh electroformed by the M cooperation solution has Ni and S element. The incorporation of S element in the Ni mesh has a profoundly effect on mechanical properties such as hardness, internal stress and so on.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.636-645
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• 2006

In order to use railway system standby power, produced 160Ah NiMH battery that would be able to substitute the lead acid battery or NiCd battery form which contain the toxic material in environment, using parallel connected 80Ah NiMH battery. And in order to develop proper electrode in the 160Ah NiMH battery, tested high rate discharge performance of the ternary electrolyte. 160Ah NiMH battery evaluated the various test in order to use railway system standby power.

• Bulletin of the Korean Chemical Society
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• v.25 no.4
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• pp.545-548
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• 2004

A sensitive, selective and rapid method for the determination of nickel based on the rapid reaction of nickel(II) with QADMAA and the solid phase extraction of the Ni(II)-QADMAA chelate with $C_{18}$ membrane disks has been developed. In the presence of pH 6.0 buffer solution and sodium dodecyl sulfonate (SDS) medium, QADMAA reacts with nickel to form a violet complex of a molar ratio of 1 : 2 (nickel to QADMAA). This chelate was enriched by solid phase extraction with $C_{18}$ membrane disks. An enrichment factor of 50 was obtained by elution of the chelates form the disks with the minimal amount of isopentyl alcohol. The molar absorptivity of the chelate was $1.32{\times}10^5L\;mol^{-1}cm^{- 1}$ at 590 nm in the measured solution. Beer's law was obeyed in the range of 0.01-0.6 ${\mu}$g/mL. This method was applied to the determination of nickel in water and biological samples with good results.

• Journal of Surface Science and Engineering
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• v.20 no.1
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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.

• Journal of Surface Science and Engineering
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• v.39 no.1
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• pp.13-17
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• 2006

The effects of an organic additive, naphthalene trisulfonic acid (NTSA), contained in the nickel sulfamate bath on the surface properties of the electrodeposited nickel layer were investigated through electrochemical technique, x-ray diffraction analysis, and microscopic observation. The addition of NTSA facilitated the oxidation process of electrodeposited nickel layer during anodic scan and also increased the hardness and internal stress of the nickel film as the applied current density became higher. It seems that NTSA modulated the deposit structure during electrodeposition and so induced higher distribution of (110) orientation with respect to (200). With the increase of the NTSA in the bath, nickel layer was formed in small grain size, which resulted in enhanced surface evenness and brightness.

• Corrosion Science and Technology
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• v.18 no.4
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• pp.148-153
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• 2019

Pure nickel with a thickness of 1 mm was plated on type 304 stainless steels and low alloy steels (JIS G3131 SPHC) by electrolytic plating method in a circulating plating bath. Plating performance, mechanical properties, and surface characteristics were evaluated in terms of pretreatment process, anode material, pH, current density, and flow rate of the plating solution. Addition of hydrochloric acid during pre-treatment process improved the adhesion performance of plating. To improve plating efficiency, it is desirable to use S-nickel rather than electrolytic nickel. The use of S-nickel was also confirmed to be desirable for maintaining the pH and concentration of the plated solution. The defect of the plating using S-nickel anode produced pit on the surface. However, it is believed that proper control can be obtained by increasing the flow rate. Internal stress and hardness values of electrolytic nickel plating according to current density need to be carried out with further studies.

• Journal of the Korean Vacuum Society
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• v.3 no.1
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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.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1303-1304
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• 2008

Nickel wire of 0.2mm diameter and 50mm in length was exploded in ethanol for Ni nanopower synthesis. The waveform of discharge current shows that the process can be divided by ohmic heating phase and plasma state. The Ni nanopowder classified after synthesis has 100nm of mean diameter.