• 제목/요약/키워드: $^{63}Ni$

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Shear Strength of the ${Cu_6}{Sn_5}$-dispersed Sn-Pb Solder Bumps Fabricated by Screen Printing Process (${Cu_6}{Sn_5}$를 분산시켜 스크린 프린팅법으로 제조한 Sn-Pb 솔더범프의 전단강도)

  • Choe, Jin-Won;Lee, Gwang-Eung;Cha, Ho-Seop;O, Tae-Seong
    • Korean Journal of Materials Research
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    • v.10 no.12
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    • pp.799-806
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    • 2000
  • Cu$_{6}$Sn$_{5}$-dispersed 63Sn-37Pb solder bumps of 760$\mu\textrm{m}$ size were fabricated on Au(0.5$\mu\textrm{m}$)/Ni(5$\mu\textrm{m}$)/Cu(27$\pm$20$\mu\textrm{m}$) BGA substrates by screen printing process, and their shear strength were characterized with variations of dwell time at reflow peak temperature and aging time at 15$0^{\circ}C$ . With dwell time of 30 seconds at reflow peak temperature, the solder bumps with Cu$_{6}$Sn$_{5}$ dispersion exhibited higher shear strength than the value of the 63Sn-37Pb solder bump. With increasing the dwell time longer than 60 seconds, however the shear strength of the Cu$_{6}$Sn$_{5}$-dispersed solder bumps became lower than that the 63Sn-37Pb solder bumps. The failure surface of the solder bumps could be divided into two legions of slow crack propagation and critical crack propagation. The shear strength of the solder bumps was inversely proportional to the slow crack propagation length, regardless of the dwell time at peak temperature, aging time at 150 $^{\circ}C$ and the volume fraction of Cu$_{6}$Sn$_{5}$ dispersion.> 5/ dispersion.

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Recovery of Rare Metals from the Waste Secondary Lithium Ion Battery Cathode Active Materials Using Lactic Acid and Oxalic acid (젖산과 옥살산을 이용한 폐 이차 리튬이온 전지 양극 활물질로부터 희유금속들의 회수)

  • Kim, Younjung;Han, Ji Sun;Choi, Sik Young;Oh, In-Gyung;Hong, Yong Pyo;Ryoo, Keon Sang
    • Journal of the Korean Chemical Society
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    • v.63 no.6
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    • pp.446-452
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    • 2019
  • We have developed a method that can leach Co, Mn, and Ni in the cathode active material safely using lactic acid. When cathode active material was leached by lactic acid, lactic acid showed the highest efficiency at 2 N than 1 N and above 4 N concentration. When the cathode active material was added incrementally into the solution of lactic acid, the maximum solubility was 30 g/L at 2 N concentration. Oxalic acid was added in the solution of lactic acid and it showed that rare metals represent the most economical recovery efficiency at 4 g/L. Based on this study, it was found that the optimal condition for recovery of rare metals from cathode active material is oxalic acid : cathode active material = 7 : 1 as a ratio of weight. In addition, it was observed that the precipitate produced by oxalic acid is a polynuclear crystalline material bonded with 3 components of Co, Ni, and Mn.

Studies on the Flora of Mulgun-ni and Mijo-ri Windbreak Forests in Namhaegun, Kyungsangnamdo (경상남도 남해군 물건리$\cdot$미조리 방풍림의 식물상연구)

  • Oh Hyun-Kyung;Kim Yong-Shik;Koh Myong-Hee
    • Korean Journal of Environment and Ecology
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    • v.19 no.3
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    • pp.246-257
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    • 2005
  • The flora was summarized as 176 taxa; 66families, 135genera, 147species,25varieties and 4forms in Mulgun-ni Windbreak Forest and 1531axa; 63families, 123genera, 138species, 13varieties and 2forms in Mijo-ri Windbreak Forest. The Specific Plant Species which is categorized by the Minisoy of Environment, Korea, was summarized as 24 taxa for the Degree I and 3 taxa for the Degree III in Mulgun-ni Windbreak Forest: Eusraphis japonica(Staphyleaceae), Aphananthe aspera(Ulmaceae), Ficus erecta(Moraceae), Puccinellia coreensis (Gramineae), Rhus succedanea(Anacariaceae), Koelreuteria paniculata(Sapindaceae) and 28 taxa for the Degree 1 and 7 taxa for the Degree III in Mijo-ri Windbreak Forests: Castanopsis cuspidata val. sieboldii(Fagaceae), Rubus h irsutus(Rosaceae), Elaeagnus macrophylla(Elaeagnaceae), Cinnamom urn japonic urn (Lauraceae), flex integra (Aquifuliaceae) and Lazoste lancEyolia(Lauraceae). From the enlisted vascular plants surveyed, the naturalized plants were 17 taxa in Mulgun-ni Windbreak Forest and 9 taxa in Mijo-ri Windbreak Forests with the Naturalization Index was 9.7 percent and 5.9 percent respectively.

Synthesis of Conjugated Linoleic Acid Methylester using Heterogeneous Catalysts (불균일계 촉매에 의한 공액 리놀레산 메틸에스테르의 합성)

  • Yuk, Jeong-Suk;Lee, Sang-Jun;Kim, Nam-Kyun;Kim, Young-Wun;Yoon, Byeong-Tae
    • Applied Chemistry for Engineering
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    • v.24 no.3
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    • pp.291-298
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    • 2013
  • Conjugated linoleic acid methylester was synthesized through isomerization of linoleic acid methylester by using heterogeneous catalysts. As for heterogeneous catalysts, Ni supported zeolite type catalysts were used. H zoelite Y (HY) were ion exchanged with KCl aqueous solution to synthesize K zeolite Y (KY), and with impregnation method, Ni supported zeolite catalysts were synthesized. Catalysts were used after pre-treatment by using hydrogen. HY catalysts showed a high conversion at low temperatures; but a low selectivity for conjugation reaction. KY catalysts showed a low conversion at low temperatures; but a similar conversion with HY catalysts at high temperatures while a high selectivity at low temperatures. As a result, 4 wt% Ni/KY720 recorded the high conjugation yield of 63.4% at 220.

Estimation of Radioactive Inventory for a major component of Reactor in Decommissioning (해체시 원자로 주요 구성품에 대한 방사능 재고량 평가)

  • Hak-Soo Kim;Ki-Doo Kang;Kyoung-Doek Kim;Chan-Woo Jeong
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.2 no.1
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    • pp.69-75
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    • 2004
  • DORT and ORIGEN2 code were used for calculation of neutron flux and inventory in reactor pressure vessel(RPV) of Kori unit-1, To calculate neutron flux using DORT code, the reactor was divided into 94 mesh from the center of core to RPV and from 0 to 45 degree along the azimuth. The cross-sections of main nuclides were recalculated using neutron flux in the RPV region. The results showed that 95% of the total activity in RPV came from the nuclides of $^{55}$ Fe, $^{60}$ Co, $^{59}$ Ni and $^{63}$ Ni. And the total activity with cooling of more than 50 years after decommissioning was no more than 0.2% of at the time of shutdown. Considering the weight of RPV is 210 tons, the initial total activity of RPV reached 5.25${\times}$10$^{6}$ GBq. To verify results of ORIGEN2 calculation, comparison between calculated and measured value at RPV of Kori unit-1 was peformed. The comparison results showed a good agreement.

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HEAVY METAL CONTINT IN THE SEDIMENTS FROM THE CONTINENTAL SHELF AROUND JEJU ISLAND AND SOUTHERN COASTAL AREA, KOREA (濟州道周圍 및 南海沿岸 堆積物中의 重金屬含量)

  • 석봉출;박병권
    • 한국해양학회지
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    • v.18 no.1
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    • pp.29-42
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    • 1983
  • This stidy was intended to investigate the heavy metal contents in the bottom sediments of the continental shelt around the Jeju Island and ot the southern coastal area of the Korean Peninsula. For this study 39 bottom sedinent samples were taken from the study area using Phleger gramity corer and Snapper. The average contents of heavy metals were 59.1 ppm Zn, 362.6 ppm Mn, 63.8 ppm Cr, 15.7 ppm Pb, 10.0 ppm Co, 28.9 ppm Ni, 10.5 ppm Cu, and 2.7% Fe in the surficial sediments around the Jejr Island; and 79.ppm Zn, 384 ppm Mn, 8.6 ppm Pb, 17.8 ppm Ni, 23.2 ppm Cu, and 1.59 % fe in those of nearsgore of the southern coastal area respectively. The heavy metal contents were higher in the northwestern part around the Jeju Island compared to those in other region. However, these tendencies were not the result of pollution, but of the differences of grain size of the sedimenrs. In the nearshore of the southern coast, the heavy metal contents did not show any geographical tendency. However, those of Masan and Jinhae Bays wew higher than those of the other region. These seemed to be caused by waste disposal from the industrial compsex located at the adjacent land. Nevertheless these values of heavy metal content except for Zn and Cu in Masan Bay and inner bay of Jinhae are lower than the average values of the each world-wide data of the nearshore sedimentl. The pair correlations of the cach heavy metal elements were calculated by regressino analysis using VAX 780 computer. the following pair elements, such as Zn-Cu, Ni-Cu, Fe-cu, Cr-Cu, Co-Zn, Ni-Zn, Cr-Zn, Ni-Co, Fe-Co, Cr-Co, Fe-Ni, Cr-Ni and Cr-Fe show closely posetive linear correlations in the sediments around the Jeju Island. In general, the heavy metal content increases in proportion to the increase of the mean values of the grain size of the sediments around the Jeju Island. In the southern coastal area, in gineral, thepair correlations of each heavy metal elements did not southern coastal area, in general, the pair correlatttttions of rach heavy metal elements did not show any positive correlation except for the positive linear correlations of Cu-Zn, Cu-ni and Ni-Mn. It is interpreted as a result of the differences of the physecochemical environment of the sampling sites and also of the influences of the ondustrial wastes from the manufacturing factores located at the coastal zone of the study area.

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Cobalt and Nickel Ferrocyanide-Functionalized Magnetic Adsorbents for the Removal of Radioactive Cesium (방사성 세슘 제거를 위한 코발트 혹은 니켈 페로시아나이드가 도입된 자성흡착제)

  • Hwang, Kyu Sun;Park, Chan Woo;Lee, Kune-Woo;Park, So-Jin;Yang, Hee-Man
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.1
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    • pp.15-26
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    • 2017
  • Cobalt ferrocyanide (CoFC) or nickel ferrocyanide (NiFC) magnetic nanoparticles (MNPs) were fabricated for efficient removal of radioactive cesium, followed by rapid magnetic separation of the absorbent from contaminated water. The $Fe_3O_4$ nanoparticles, synthesized using a co-precipitation method, were coated with succinic acid (SA) to immobilize the Co or Ni ions through metal coordination to carboxyl groups in the SA. CoFC or NiFC was subsequently formed on the surfaces of the MNPs as Co or Ni ions coordinated with the hexacyanoferrate ions. The CoFC-MNPs and NiFC-MNPs possess good saturation magnetization values ($43.2emu{\cdot}g^{-1}$ for the CoFC-MNPs, and $47.7emu{\cdot}g^{-1}$ for the NiFC-MNPs). The fabricated CoFC-MNPs and NiFC-MNPs were characterized by XRD, FT-IR, TEM, and DLS. The adsorption capability of the CoFC-MNPs and NiFC-MNPs in removing cesium ions from water was also investigated. Batch experiments revealed that the maximum adsorption capacity values were $15.63mg{\cdot}g^{-1}$ (CoFC-MNPs) and $12.11mg{\cdot}g^{-1}$ (NiFC-MNPs). Langmuir/Freundlich adsorption isotherm equations were used to fit the experimental data and evaluate the adsorption process. The CoFC-MNPs and NiFC-MNPs exhibited a removal efficiency exceeding 99.09% for radioactive cesium from $^{137}Cs$ solution ($18-21Bq{\cdot}g^{-1}$). The adsorbent selectively adsorbed $^{137}Cs$, even in the presence of competing cations.

Fabrication and Characterization of Hybrid NTC Thermistor Films with Conducting Oxide Particles by an Aerosol-Deposition Process (상온 분사 공정에 의한 산화물전도 입자 복합 하이브리드 NTC 서미스터 필름의 제작 및 특성)

  • Kang, Ju-Eun;Ryu, Jungho;Choi, Jong-Jin;Yoon, Woon-Ha;Kim, Jong-Woo;Ahn, Cheol-Woo;Choi, Joon Hwan;Park, Dong-Soo;Kim, Yang-Do
    • Journal of the Korean Ceramic Society
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    • v.50 no.1
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    • pp.63-69
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    • 2013
  • Negative-temperature coefficient (NTC) thermistors based on nickel manganite spinel ($NiMn_2O_4$) are widely used for many applications, such as sensors and temperature compensators, due to their good thermistor characteristics and stabilities. However, to achieve thermistors with a high NTC B constant, which is an important figure of merit pertaining to the degree of temperature sensitivity, the activation energy should be high such that high resistivity at ambient temperatures results. To obtain a high B constant and low resistivity, Al and Si modified spinel structured $Ni_{0.6}Si_{0.2}Al_{0.6}Mn_{1.6}O_4$ hybrid thick films with the conducting metal oxide of $LaNiO_3$ were fabricated on a glass substrate by aerosol deposition at room temperature (RT). The NTC-$LaNiO_3$ hybrid thick films showed resistivity as low as < $100k{\Omega}\;cm$ at $90^{\circ}C$, which is one or two orders of magnitude lower than that of the monolithic NTC films, while retaining a high B constant of $NiMn_2O_4$ of over 5500 K when 20 wt% $LaNiO_3$ was added without a post-thermal treatment. These phenomena are explained by the percolation threshold mechanism.

Studies on Heavy Metal Ion Adsorption by Soils. -(Part 1) PH and phosphate effects on the adsorption of Cd, Cu, Ni and Zn by mineral soils with low CEC and low organic carbon content (중금속(重金屬) 이온의 토양(土壤) 흡착에 관한 연구 -(제1보) CEC 및 유기탄소 함량이 낮은 광물토양에의 Cd, Cu, Ni, 및 Zn의 흡착과 이에 미치는 pH 및 인산의 효과-)

  • Kim, Myung-Jong;Motto, Harry L.
    • Applied Biological Chemistry
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    • v.20 no.3
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    • pp.300-309
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    • 1977
  • The information related to the heavy metal pollution in the environment was obtained from studies on the effects of pH, phosphate and soil properties on the adsorption of metal ions (Cd, Cu, Ni, and Zn) by soils. Three soil materials; soil 1 with low CEC (8.2 me/100g) and low organic carbon content (0.34%); soil 2 with high CEC (36.4 me/100g) and low organic carbon content (1.8%) and soil 3 with high CEC (49.9 me/100g) and high organic carbon content (14.7%) were used. Soils were adjusted to several pH's and equilibrated with metal ion mixtures of 4 different concentrations, each having equal equivalents of each metal ion (0.63, 1.88, 3.12 and 4.38 micromoles per one gram soil with and without 10 micromoles of phosphate per one gram soil). Reported here are the results of the equilibrium study on soil I. The rest of the results on soil 2 and soil 3 will be repoted subsequeutly. Generally higher metal ion concentration solution resulted in higher final metal ion concentrations in the equilibrated solution and phosphate had minimal effect except it tended to enhance removal of cadmium and zinc from equilibrated solutions while it tended to decrease the removal of copper and nickel. In soil 1, percentages of added metal ions removed at pH 5.10 were; Cu 97, Ni 69, Cd 63, and Zn 55, while increasing pH to 6.40, they were increased to Cu 90.9, Zn 99, Ni 96, and Cd 92 per As initial metal ion concentration increased, final metal ion concentrations in the equilibrated solution showed a relationship with pH of the system as they fit to the equation $p[M^{++}]=a$ pH+b where $p[M^{++}]=-log$[metal ion concentration in Mol/liter]. The magnitude of pH and soil effects were reflected in slope (a) of the equation, and were different among metal ions and soils. Slopes (a) for metal ions in the aqueous system are all 2. In soil 1 they were; Zn 1.23, Cu 0.99, Ni 0.69 and Cd 0.59 at highest concentration. The adsorption of Cd, Ni, and Zn in soil 1 could be represented by the Iangmuir isotherm. However, construction of the Iangmuir isotherm required the correction for pH differences.

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Micorstructure of Sn1.8Bi0.8Cu0.6In alloy during thermal aging (시료에 따른 Sn1.8Bi0.8Cu0.6In솔더의 미세구조)

  • Lee Jae Sik;Jeon Ju Seon;Park Jong U;Jeong Jae Pil
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2003.11a
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    • pp.94-98
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    • 2003
  • The microstructure of Sn1.8Bi0.8Cu0.6In alloys was evaluated at various aging time. The bumps of Sn1.8Bi0.8Cu0.6In alloys after reflowed at $250^{\circ}C$ were well-formed and had 260um height. The craters on the bumps, however, were observed. Intermetallic compounds formed on the interface between so]der and Cu/Ni UBM were consist of $(Cu,Ni)_6Sn_5$. As aging goes on up to 1000hours, the composition of Ni changed from $6.63\%$ at initial stage(as-reflowed) to $13.47\%$ at final stage(1000hours aging ). In addition, after 500hours aging, the floating of IMC to the solder was observed.

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