• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.24-24
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• 2009

ENIG(Electroless Nickel Immersion Gold) is the surface treatment method that is used most widely at fine pitch's SMT and BGA packaging process. In this paper, we have studied the effect of P content variation during ENIG process on those phenomena related to the solder joint. The effect of P content was discussed using the results obtained from FE-SEM, EPMA, EDS and FIB. Finally, it was concluded that the more P-content in Ni layer, the thicker P-rich layer.

• 한국표면공학회지
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• 제51권3호
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• pp.172-178
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• 2018

In this paper, effects of potassium permanganate, pottasium dichromate, sodium molybdate on lean duplex stainless steel were studied by GDOES, OCP, potentiodynamic curves. The stainless steels were chemically passivated in each nitric acid solutions containing 4wt.% oxidants for 1 hour. As a result, when potassium dichromate or sodium molybdate was added, content of Fe was decreased and content of Cr was increased. Consequently, corrosion resistance of passive film was increased. But in case of potassium permanganate was added, contrastively, content of Fe was increased and content of Cr was decreased. So corrosion resistance was decreased. Adding sodium molybdate in nitric acid for chemical surface treatment process was the most effective among oxidants and also it showed the most stable anti-corrosion in SST.

• Asian-Australasian Journal of Animal Sciences
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• 제1권2호
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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.

• 한국환경생태학회지
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• 제12권1호
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• pp.22-29
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• 1998

충남지역의 사문암과 변성암 및 흑색셰일지역의 암석, 토양 및 그 위에서 생육하는 리기다소나무의 미량원소 함량을 측정하여 모암별 토양의 원소함량과 식물체의 흡수확계를 조사하였다. Ni, Cr 및 Co 함량은 사문암에서 매우 높았으며, Zn, Mo 및 Fe 함량은 변성암에서 높았다. 흑색셰일의 이들 원소는 사문암과 변성암보다 공히 낮았다. 사문암 토양의 Ni, Cr 및 Co 함량은 매우 높았으며, Zn과 Fe 함량은 사문암+변성암 혼합풍화토 및 흑색셰일 토양에서 높았다. 풍화토의 미량원소 함량은 암석의 함량보다 낮았으며, 그 패턴은 Mo를 제외하고는 모두 유사하였다. 사문암 풍화토의 pH 범위는 7.73~9.55로 매우 높았다. 사문암지역 리기다소나무의 Cr 흡수량은 토양내 Cr함량에 비하여 낮았으며, Zn 은 토양내의 원소함량에 비하여 리기다소나무에 의한 흡수량이 높았다. 리기다소나무에 의하여 흡수된 Ni, Fe 및 Co 함량에 대한 Fe/Ni, Co/Ni 비율은 사문암풍화토에서 가장 낮았다.

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.597-600
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• 2014

In this work, the electromagnetic interference shielding effectiveness (EMI-SE) of carbon nanotube/carbon fiber-reinforced HDPE matrix composites are investigated with various preparation conditions, such as the carbon fiber and carbon nanotube content, the presence of metal additives, as well as mixing speed and time. It was found that the EMI-SE of the composites increased with filler contents and metal additives. These results indicate that the content and length of carbonaceous fillers determine the electric networks in the composites, resulting in the control of the EMI-SE of the composites.

• 한국식품영양과학회지
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• 제9권1호
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• pp.51-58
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• 1980

1976년(年) 6월(月)부터 10월(月)사이에 경남(慶南) 충무(忠武) 일원(一圓)에서 비교적(比較的) 이용도(利用度)가 높고 생산량(生産量)이 많은 해조류(海藻類) 16종(種)을 채집(採集)하여 중금속(重金屬)을 중심(中心)으로 한 무기성분(無機成分)을 분석(分析)하여 다음과 같은 결과(結果)를 얻었다. 1) 일반적(一般的)으로 녹조류(綠藻類)에는 철, 니켈 등의 함량(含量)이 높은 반면 갈조류(褐藻類)에는 납, 니켈 및 망간 등이 낮은 함량(含量)을 보였으며 카드뭄, 구리, 니켈 및 마그네슘등에서도 몇 가지 해조류(海藻類)가 특별(特別)한 함량차이(含量差異)를 나타내었다. 2) 카드뭄함량(含量)은 녹조류(綠藻類) $0.58{\sim}1.04ppm$(평균(平均) : 0.85ppm), 갈조류(褐藻類) $0.32{\sim}2.10ppm$ (평균(平均) : 1.08ppm), 홍조류(紅藻類) $0.54{\sim}1.70ppm$ (평균(平均) : 1.04ppm) 이었는데 김, 미역, 다시마 등은 $0.3{\sim}0.6ppm$의 분포(分布)로써 예상외로 낮은 함량(含量)을 나타내었다. 3) 납의 함량(含量)은 녹조류(綠藻類) $0.67{\sim}1.40ppm$(平均 : 1.03 ppm), 갈조류(褐藻類)$0.60{\sim}1.00ppm$(平均 : 0.82ppm), 홍조류(紅藻類) $0.56{\sim}2.40ppm$(平均 : 1.28ppm)으로써 어패류(魚貝類)에 비(比)해서 상당히 낮은 함량(含量)이었다. 4) 구리의 함량(含量)은 녹조류(綠藻類) $10.8{\sim}24.2ppm$ (평균(平均) : 18.95ppm), 갈조류(褐藻類) $7.4{\sim}24.6ppm$ (평균(平均) : 18.16ppm), 홍조류(紅藻類) $6.4{\sim}31.2ppm$ (平均 : 19.94ppm)의 분포(分布)이었는데 몇 종(種)의 해조(海藻)를 제외(除外)하고는 전반적(全般的)으로 높은 함량(含量)을 보이고 있다. 5) 철의 함량(含量)은 녹조류(綠藻類) $686.4{\sim}1,159.0ppm$(평균(平均) : 916.5ppm), 갈조류(褐藻類) $131.0{\sim}499.2ppm$ (平均 : 310.16ppm), 홍조류(紅藻類) $156.0{\sim}530.4ppm$(平均 : 248.2ppm)으로써 녹조류(綠藻類)는 다른 해조류(海藻類)에 비(比)하여 특(特)히 높은 값을 나타내었다. 6) 망간의 함량(含量)은 녹조류(綠藻類) $48{\sim}221ppm$ (평균(平均) : 157.25ppm), 갈조류(褐藻類) $12{\sim}65ppm$ (평균(平均) : 41ppm), 홍조류(紅藻類) $72{\sim}162ppm$ (평균(平均) : 121 ppm)의 분포(分布)로써 갈조류(褐藻類)는 특(特)히 낮은 함량(含量)을 나타내었다. 7) 아연의 함량(含量)은 녹조류(綠藻類) $191.3{\sim}451.1ppm$(평균(平均) : 290.05ppm), 갈조류(褐藻類) $89.9{\sim}374.2ppm$(평균(平均) : 202.64ppm), 홍조류(紅藻類) $106.4{\sim}281.4ppm$ (평균(平均) : 188.93ppm)이었다. 8) 마그네슘함량(含量)은 녹조류(綠藻類) $0.48{\sim}1.83%$ (평균(平均) : 1.27%), 갈조류(褐藻類)$1.04{\sim}1.71%$(평균(平均) : 1.21%), 홍조류(紅藻類) $0.42{\sim}1.24%$(평균(平均) : 0.97%)이었다. 9) 불소는 해조류중(海藻類中)에 특(特)히 많이 함유(含有)되어 있어서 녹조류(綠藻類) $29.2{\sim}92.7ppm$(평균(平均) : 53.03ppm), 갈조류(褐藻類) $33.3{\sim}43.5ppm$(평균(平均) : 39.18ppm), 홍조류(紅藻類) $32.4{\sim}59.0ppm$(평균(平均) : 44.84ppm) 이었다.

• 한국환경보건학회지
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• 제9권2호
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• pp.67-74
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• 1983

An experimental study was carried out to determine the degree of contamination of cyanide and metals in each stork's (Ciconia c. boyciana) organ. The samples used for this experiment were gullet, respiratory tract, stomach content, rectum, lung, liver, heart, pancreas, gall, kidney, and muscles. Those samples were isolated by Conway microdiffusion method and determined by UV spectrophotometry for the cyanide, on the other hand, the samples for metals were dissolved by mercury digestion apparatus and analyzed by atomic absorption spectrophotometry. The results are as follows: 1) The quantities of cyanide accumulated in each organ were from 0.05 to 2.57 ppm and concentration of those in tissues was in order of 2.57 ppm in stomach content, 2.13 ppm in lung, 1.58 ppm in kidney, 1.22 ppm in gall, 0.52 ppm in pancreas, 0.32 ppm in heart, 0.25 ppm in rectum, 0.20 ppm in gullet, 0.19 ppm in liver, 0.07 ppm in muscles and 0.05 ppm in respiratory tract. 2) The calcium content is in a range of 10.89-105.74 ppm, iron is 2.47-557.70 ppm, zinc is 2.37-23.62 ppm, cupper is < 0.1- 1.76 ppm and cadmium, nickel, cobalt and lead is beyond 0.5 ppm, respectively.

• Journal of Magnetics
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• 제20권3호
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• pp.246-251
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• 2015

This study was aimed to study the effect of Zn content on the hyperfine parameters and the structural variation of $Ni_{1-x}Zn_xFe_2O_4$ for x = 0, 0.2, 0.4, 0.6, and 0.8. To achieve this, a sol-gel route was used for the preparation of samples and the obtained ferrites were investigated by X-ray diffraction, scanning electron microscopy, and $M{\ddot{o}}ssbauer$ spectroscopy. The formation of spinel phase without any impurity peak was identified by X-ray diffraction of all the samples. Moreover, the estimated crystallite size by X-ray line broadening indicates a decrease with increasing Zn content. This result was in agreement with the scanning electron microscopy result, indicating the reduction in grain growth with further zinc substitution. The room-temperature $M{\ddot{o}}ssbauer$ spectra show that the hyperfine fields at both the A and B sites decreased with increasing Zn content; however, the rate of reduction is not the same for different sites. Moreover, the best fit parameter showed that the quadrupole splitting values of B site increased from the pure nickel ferrite to the sample with x = 0.8.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2001년도 추계학술발표회 초록집
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• pp.56-56
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• 2001

Ni-W alloy deposit is one of the best alternatives to hard chromium plating because of its good mechanical properties (high hardness, high strength, and good wear resistance). Ni-W alloy is deposited from weakly acidic or alkaline electrolytic bath with nickel sulfate, sodium tungstate or APT, and some kinds of organic hydroxy-acid complex and ammonia salts. W content of the deposit can be changed from 0 to 5Owt% and the coating with high W content is more attracted. But, meanwhile, the deposited layers are always found high internal stress, which cause them to become brittle and to bond insufficiently with the substrate. On the second hand, as the W content is incresed, the current efficiency reduced, which results in large quantities of hydrogen evolution and then produces bubbles on surface and pitting appearance In this paper, the influence of some additives on Ni-W alloy electroplating was investigated by means of compositional analysis and SEM. The initial results showed that 2-butyne-1,4-diol was the best brightener for Ni-W plating process. It could brighten and level deposit, but decreased the cathodic current efficiency. Its optimum concentration range is from O.lgjL to 0.5gjL. Besides, three kinds of additives including 2-butyne-1,4-diol were examined with Dagguchi method.

• 자원리싸이클링
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• 제24권1호
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• pp.35-42
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• 2015

본 연구는 건식제련법으로 폐 PCB를 처리하는 공정에서 슬래그 중 Ni의 용해거동에 대한 기초연구로서, CaO-$SiO_2-Al_2O_3$-MgO계 슬래그와 Cu-5 wt%Ni합금 사이의 Ni 분배거동을 1623~1823 K의 $CO_2$-CO 분위기 중에서 조사하였다. 평형산소분압이 증가할수록 Ni의 분배비는 선형적으로 증가하였으며, 이 결과로부터 Ni의 슬래그 중 용해반응은 다음과 같이 나타낼 수 있다. $$Ni(l)_{metal}+\frac{1}{2}O_2(g)NiO(l)_{slag}$$ 슬래그 중 염기성 산화물(CaO와 MgO)의 농도가 증가할수록 Ni의 분배비는 선형적으로 증가하였다. 그러나 반응 온도가 높을수록 Ni의 분배비는 선형적으로 감소하였다. 이러한 결과로부터 Ni의 분배비에 미치는 실험변수의 영향을 다중 회귀분석하여 다음과 같은 경험식을 얻었다. $${\log}L_{Ni}=0.4000{\log}P_{O2}-5.1{\times}10^{-4}T+0.3375\(\frac{X_{CaO}+X_{MgO}}{X_{SiO2}}\)$$