• Journal of Surface Science and Engineering
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• v.15 no.1
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• pp.18-23
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• 1982

The microstructure of Watts and bright ni-ckel electrodepositss is correlated with pref-erred orientation. The characteristics lamellar structure of bright nickel was atributed to the periodic adsorption of organic additives and related to cyclic fluctuations in temper-ature.

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.2
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• pp.89-98
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• 1988

Three experiments were conducted to determine whether cobalt (Co) or nickel (Ni) could prevent zinc (Zn) deficiency signs in pigs fed a high calcium (Ca) corn-soybean diet. The basal diet contained 1.3% Ca, .93% phytic acid and means of 34 to 48 ppm Zn. After weanling, pigs in experiment I were fed the basal diet for 9 weeks, and was found that 50 ppm Co or Ni for 5 weeks increased average daily weight gain (ADG) and reversed skin lesions toward normal. These effects were similar to those of 100 ppm supplemental Zn. The Zn content and alkaline phosphatase activity of serum from pigs supplemented with Co or Ni were higher at 2 weeks and 4 weeks (P<.05) than those of the basal group. Zn content of bone, liver and kidney, and alkaline phosphatase activity in bone were increase after 5 weeks of supplementation with Co or Ni. In experiments 2 and 3, addition of 54 ppm and 27 ppm of either Co or Ni increased (P<.05) ADG and decreased incidence of skin lesions except in one group supplemented with 27 ppm Ni. Supplemental Co or Ni increased Zn in serum and alkaline phosphatase activity in serum and bone in both experiments. Over all experiments, supplemental Co or Ni decreased Zn deficiency signs in the following order of effectiveness: 54 ppm Co, 54 ppm Ni, 27 ppm Co and 27 ppm Ni. The alleviation of signs of Zn deficiency by Co or Ni may have been the result of increased availability of dietary Zn.

• Journal of the Korean Magnetics Society
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• v.23 no.1
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• pp.12-17
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• 2013

Nanocrystalline nickel (Ni) tick films were synthesized by direct current electrodeposition at current density from 1 to $30mA/cm^2$ and pH = 4. The basic composition of the bath, which was prepared by dissolving Ni metal particles in HCl, was 0.2M Ni ions. The effects of the current density on the average grain size of Ni deposits were investigated by XRD and SEM techniques. The results showed that the surface roughness was decreased as the saccharin addition was increased up to 2 g/l. The experimental results showed that the increase in the current density had a considerable effect on the average grain size of the Ni deposits. The perpendicular magnetization was raised as the thickness of coating layer was increased.

• Restorative Dentistry and Endodontics
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• v.36 no.1
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• pp.1-11
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• 2011

Introduction: The aim of this paper is to discuss the mechanical and geometric features of Nickel-titanium (NiTi) rotary files and its clinical effects. NiTi rotary files have been introduced to the markets with their own geometries and claims that they have better ability for the root canal shaping than their competitors. The contents of this paper include the (possible) interrelationship between the geometries of NiTi file (eg. tip, taper, helical angle, etc) and clinical performance of the files as follows; - Fracture modes of NiTi rotary files - Non-cutting guiding tip and glide path - Taper and clinical effects - Cross-sectional area and clinical effects - Heat treatments and surface characteristics - Screw-in effect and preservation of root dentin integrity - Designs for reducing screw-in effect Conclusions: Based on the reviewed contents, clinicians may have an advice to use various brands of NiTi rotary instruments regarding their advantages which would fit for clinical situation.

• Advances in Energy Research
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• v.1 no.1
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• pp.1-12
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• 2013

In this work, we present the catalytic dehydrogenation of hydrazine borane $N_2H_4BH_3$ (HB) using supported nickel catalysts at $50^{\circ}C$. In the presence of monometallic nickel catalysts, the dehydrogenation of HB is a one-step reaction consisting of the hydrolysis of the $BH_3$ group only. The challenge is to activate nickel to make it reactive towards the $N_2H_4$ moiety of HB. A set of 52 catalysts were prepared by using 2 supports ($Al_2O_3$ and $TiO_2$), 5 nickel precursors and 3 preparation methods. For the first time, we show that the supported nickel catalysts are able to dehydrogenate the $NH_3$ moiety of HB. In our experimental conditions, the best results were obtained with 20 wt% Ni-$Al_2O_3$ and 20 wt% Ni-$TiO_2$, with ca. 190 mL $H_2+N_2$ generated over a total theoretical volume of 283 mL, suggesting $H_2$ selectivity of 37 and 32%, respectively. Both catalysts were then characterized by EDX, XPS, and XRD. Our achievement is the first step forward and opens new perspectives for developing catalysts for the total dehydrogenation of HB.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.3
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• pp.139-144
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• 2003

Nickel fine powders were prepared from nickel chloride aqueous solution containing ethanol as an organic solvent, and their oxidation behaviors were investigated. The reduction reaction by hydrazine from nickel chloride aqueous solution containing ethanol depend on reaction temperature. The reduction reaction time by hydrazine decreased with the increase of reaction temperature. By controlling reaction temperature, the products could be obtained spherical particles in the range of 0.1 $\mu\textrm{m}$~1.0 $\mu\textrm{m}$. Also, As reaction temperature increased from $40^{\circ}C$ to $80^{\circ}C$, the particle size slightly increased and had a broad size distribution owing to the presence of the coarse particles. The mean particle size and specific surface area of nickel powders prepared at $60^{\circ}C$ were 0.3 $\mu\textrm{m}$ and 31.8 $\m^2$/g, respectively. Weight loss of the powders at $300^{\circ}C$ was due to composition of $_Ni(OH)2$. In case of heat treatment at $200^{\circ}C$ in air, oxidation resistance of nickel powders was remarkable than that of as-synthesized.

• Korean Journal of Materials Research
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• v.25 no.2
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• pp.90-94
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• 2015

We prepared 8 samples of non-silver and silver-added master alloys containing silicon to confirm the existence of nickel-silicides. We then prepared products made of 14K and 18K white gold by using the prepared master alloys containing 0.25, 0.35, and 0.50 wt% silicon to check for nickel release. We then employed the EN 1811 testing standard to investigate the nickel release of the white gold products, and we also confirmed the color of the white gold products with an UV-VIS-NIR-color meter. We observed $NiSi_x$ residue in all master alloys containing more than 0.50 wt% Si with EDS-nitric acid etching. For the white gold products, we could not confirm the existence of $NiSi_x$ through XRD after aqua-regia etching. In the EN 1811 test, only the white gold products with 0.25 wt% silicon master alloys successfully passed the nickel release regulations. Moreover, we confirmed that our white gold products showed excellent Lab indices as compared to those of commercial white gold ones, and the silver-added master alloys offered a larger L index. Our results indicate that employing 0.25 wt% silicon master alloys might be suitable for white gold products without nickel-silicide defects and nickel release problems.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1419-1421
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• 1995

Nickel micro-structures are fabricated by electroless plating which shows better uniformity. Positive resist AZ4562 of 7 um thickness is patterned with minimum width of 2 um on poly-silicon as for sacrificial layer. The growth rate of Ni electroless plating is 10um/h both for the seed layer of Pt and TiW. TiW is found to be more practical than Pt, since it is very difficult to remove Pt with negligible damage to Ni structures.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3213-3218
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• 2014

A metal organic framework-supported Nickel nanoparticle (Ni-MOF-5) was successfully synthesized using a simple impregnation method. The obtained solid acid catalyst was characterized by Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen adsorption-desorption and thermogravimetric analysis (TGA). The catalyst was highly crystalline with good thermodynamic stability (up to $400^{\circ}C$) and high surface area ($699m^2g^{-1}$). The catalyst was studied for the oxidation of ethyl benzene, and the results were monitored via gas chromatography (GC) and found that the Ni-MOF-5 catalyst was highly effective for ethyl benzene oxidation. The conversion of ethyl benzene and the selectivity for acetophenone were 55.3% and 90.2%, respectively.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.985-988
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• 2008

Metal induced crystallization of a-Si with a source of Ni/Si oxide was studied. Its mechanism to induce crystallization was discussed. It was found that new source behaves an effect of self-released nickel and reducing nickel residua, so can provide a wider process tolerance; improve the uniformity and stability of TFTs.