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A Study on the Characteristics of Oil-water Separation in Non-point Source Control Facility by Coalescence Mechanism of Spiral Buoyant Media (나선형 부유 고분자 여재의 Coalescence 특성을 이용한 비점오염원 저감시설의 유수분리특성 연구)

  • Kang, Sung-Won;Kim, Seog-Ku;Kim, Young-Im;Yun, Sang-Leen;Kim, Soo-Hae;Kim, Mee-Kyung
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.8
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    • pp.950-955
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    • 2007
  • Non-point source control system which had been designed only for oil-water separation in the fields of oil refinery and garage was upgraded in this research for the removal of runoff pollutants in impervious urban area. Pollutants including oil from driveway and bridge were eliminated by two types of pathway in the system. One is the coalescence mechanism that the oil droplets in the runoff come into contact with each other in the spiral buoyant media surface and form larger coalesced droplets of oil that are carried upstream to the oil layer. The other is the precipitation that solids in runoff were settled by gravity in the system. In this research, coalescing characteristics of oil and water separation were investigated through image analyses, and efficiencies of the non-point source control system were evaluated using dust in driveway and waste engine oil. Media made of high density and high molecular weight polyethylene was indeterminate helical shape and had sleek surface by analysing SEM photographs and BET. Surface area and specific gravity of media which were measured directly were 1,428 $mm^2$ and 45.3 $kg/m^3$ respectively. From the image analyses of the oil droplets photographs which were taken by using microscope, it was proved clearly that the coalescence was the main pathway in the removal of oil from the runoff. Finally, the performances of the non-point source control system filled up with the media were suspended solid $86.6\sim95.2%$, $COD_{Cr}$, $87.3\sim95.4%$, n-Hexane extractable materials $71.8\sim94.8%$ respectively.

High-Resolution Numerical Simulations with WRF/Noah-MP in Cheongmicheon Farmland in Korea During the 2014 Special Observation Period (2014년 특별관측 기간 동안 청미천 농경지에서의 WRF/Noah-MP 고해상도 수치모의)

  • Song, Jiae;Lee, Seung-Jae;Kang, Minseok;Moon, Minkyu;Lee, Jung-Hoon;Kim, Joon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.17 no.4
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    • pp.384-398
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    • 2015
  • In this paper, the high-resolution Weather Research and Forecasting/Noah-MultiParameterization (WRF/Noah-MP) modeling system is configured for the Cheongmicheon Farmland site in Korea (CFK), and its performance in land and atmospheric simulation is evaluated using the observed data at CFK during the 2014 special observation period (21 August-10 September). In order to explore the usefulness of turning on Noah-MP dynamic vegetation in midterm simulations of surface and atmospheric variables, two numerical experiments are conducted without dynamic vegetation and with dynamic vegetation (referred to as CTL and DVG experiments, respectively). The main results are as following. 1) CTL showed a tendency of overestimating daytime net shortwave radiation, thereby surface heat fluxes and Bowen ratio. The CTL experiment showed reasonable magnitudes and timing of air temperature at 2 m and 10 m; especially the small error in simulating minimum air temperature showed high potential for predicting frost and leaf wetness duration. The CTL experiment overestimated 10-m wind and precipitation, but the beginning and ending time of precipitation were well captured. 2) When the dynamic vegetation was turned on, the WRF/Noah-MP system showed more realistic values of leaf area index (LAI), net shortwave radiation, surface heat fluxes, Bowen ratio, air temperature, wind and precipitation. The DVG experiment, where LAI is a prognostic variable, produced larger LAI than CTL, and the larger LAI showed better agreement with the observed. The simulated Bowen ratio got closer to the observed ratio, indicating reasonable surface energy partition. The DVG experiment showed patterns similar to CTL, with differences for maximum air temperature. Both experiments showed faster rising of 10-m air temperature during the morning growth hours, presumably due to the rapid growth of daytime mixed layers in the Yonsei University (YSU) boundary layer scheme. The DVG experiment decreased errors in simulating 10-m wind and precipitation. 3) As horizontal resolution increases, the models did not show practical improvement in simulation performance for surface fluxes, air temperature, wind and precipitation, and required three-dimensional observation for more agricultural land spots as well as consistency in model topography and land cover data.

Lipid Composition of Purple Shell and Abalone (피뿔고둥과 전복의 지질조성에 관한 연구)

  • YOON Ho-Dong;BYUN Han-Seok;KIM Seon-Bong;PARK Young-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.19 no.5
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    • pp.446-452
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    • 1986
  • This paper presents the composition of neutral and polar lipids obtained from puple shell, Rapana venosa and the abalone, Haliotis discus hannai. The fatty acid composition and the classification of neutral lipids from two species were determined by gas chromatography (GLC) and thin layer chromatography (TLC). Total lipid contents of samples were $0.5\%$ in purple shell and $0.4\%$ in the abalone. The predominant fatty acids of total lipids were eicosapentaenoic acid ($19.30\%$). eicosenoic acid ($12.10\%$) and palmitic acid ($11.77\%$) in the purple shell, and palmitic acid ($21.29\%$), oleic acid ($14.55\%$) and linoleic acid ($14.21\%$) in the abalone. The lipid composition of non-polar lipid fractions in purple shell and abalone was separated and identified as free sterol, free fatty acid, triglyceride and hydrocarbon & esterified sterol by TLC. The contents of triglyceride from both neutral lipids were shown more abundant than any other subclasses. The main fatty acids of neutral lipids were eicosapentaenoic acid ($18.6\%$), palmitic acid ($14.90\%$) and eicosenoic acid ($14.76\%$) in the purple shell, and palmitic acid ($28.12\%$), oleic acid($20.5\%$) and myristic acid ($12.5\%$) in the abalone. Eicosapentaenoic acid ($17.57\%$), stearic acid ($13.26\%$) and eicosatetraenoic acid ($11.24\%$) were important fatty acids of glycolipid in the purple shell, and myristic acid ($12.75\%$), stearic acid ($12.10\%$) and eicosatetraenoic acid ($10.64\%$) in the abalone. The major fatty acids of phospholipids were eicosapentaenoic acid ($20.18\%$), palmitic acid ($11.26\%$) and eicosenoic acid ($10.90\%$) in the purple shell, and palmitic acid ($21.10\%$), eicosapentaenoic acid ($12.90\%$) and oleic acid($11.13\%$) in the abalone.

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Clinical review of Typhoid Fever Patients (장티브스에 관한 임상적 관찰)

  • 최정신
    • Journal of Korean Academy of Nursing
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    • v.6 no.1
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    • pp.60-71
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    • 1976
  • The author reviewed the medical records of 96 typhoid fever patients who were diagnosed, admitted, and treated at Sea grave Memorial Hospital from January 1 , 1973 through August 31, 1975. Diagnosis was determined by clinical observation, aerology and bacteriology, eighty patients were treated medically, the remaining 16 patients required surgical intervention. The following results were obtained: 1) The age distribution of the patients revealed that 33.3% wert between 10 and 19 years old 21.9% were between 20 and 29, and 19.8% were between 30 and 39. The majority of patients were from these more active age groups. Male to female sex ratio was 1.3 : 1 2) Seasonal distribution was observed. Most illness occurred in the summer and autumn month 5. 3) 84. 3%of the patients came from farm families. 4) Duration between onset and admission averaged 16.0 days. The group without compilations was admitted after an average of 15. 1 days; The group with complications was ad-matted after an average of 19.4 days. 5) Methods of treatment before admission were as follows: 10.4% at medical clinics, 61, 5% at pharmacies (antibiotics 47.9%, other. drugs 13.5%), 7.3% by herb medications, 20.8% had no treatment. 6) Main clinical symptoms were as follows: fever 93.8%, headache 47.9%, abdominal pain 47.9%, chills 38.5%, cough 36.5%, general weakness 26.0%, nausea e vomiting 24.0% and generalized pain 21.9%. 7) Temperature of patients on admission: 22.9% were 39f or more, 67.6% were between 37℃ and 38℃, and 9.4% were 37℃ or less. 8) Occurrence of intensional bleeding after onset of disease averaged 9.3 days; perforation occurred at an average of 19. 1 days. 9) Interval between onset of major complication and surgical intervention averaged 2.8 days. 10) Among the 68 patients who underwent the bacteriological test the positive rate was 44.1% (30). The positive ,ales to, each separate culture method were as follows: 20.4% in the blood culture, 40.4% in the stool culture and 6.7% in the urine culture. Among these bacteriological positive patients 15 patients had a negative results or less than 160 titer of vidal reaction. 11) The initial vidal test of the total group showed a counts of 160 titer or more in 60.4% and less than 160 titer in 39.6%, 12) W. B. C. Counts in the uncomplicated group indicated that 32.5% were 6,000/㎣ or less, 47.5% were between 6,000 and 10,000, arid 20.0% were 10,000/㎣ or more. In the complicated group, 37.6% were 6,000/㎣ or less, 25,0% were 6,000-10,000/㎣ and 37.6% were 10,000/㎣ or more. 13) Duration of hospital stay of the patients averaged 6.4 days in the uncomplicated group and 12.7 days in the complicated group. 14) Subdiaphragmatic free air simple X-ray was found in 91.7% of the perforated cases. 15) Duration of antibiotic therapy until an febrile state was attained averaged 4.8 days in the uncomplicated group and 6.5 days in the complicated group. 16) Operative procedures were as follows: one layer simple closure of their perforation with or without debasement in 56.3%, drainage only in 6.3%, small bowel resection with primary anastomosis in 18.8% , externalization in 6.3%, cholecystectomy in 6.3%, The clinical findings of this study suggest the following recommendations. According to Top's report; 1% of typhoid fever patients treated with chlorarnphenicol and 2% of patients treated with other drugs become chronic carriers. Therefore, importance should be given to the strict control of these carriers. Immunization, improvement of sanitation and living standards are all needed for the prevention and treatment of disease, but a more serious problem is a lack of knowledge on the part of patients and their families. Thus it is most urgent to enlighten the citizens about the transmission and hygiene related to contagious disease. Legal restriction of sale of antibiotics at drug stores without a physician's prescription is an urgent matter for public health administrators. An even more important nursing responsibility is the reemphasis on health education both in the clinical setting and in the home.

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Analysis of the Cold Air Flow in Suwon for the Application of Urban Wind Corridor (도시 바람길 활용을 위한 수원시 찬공기 유동 분석)

  • CHA, Jae-Gyu;CHOI, Tae-Young;KANG, Da-In;JUNG, Eung-Ho
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.4
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    • pp.24-38
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    • 2019
  • Due to the dramatic spatial changes caused by industrialization, environmental problems such as air pollution and urban heat island phenomenon, etc. are occurring in cities. In this case, the wind corridor, which is a passage through which fresh and cool air generated in forests outside cities move to the downtown, can be used as a spatial planning method for improving urban environmental problems. Cold air is determined by the characteristics of the flow depending on the topography and land use of cities, and based on this, the medium- and long-term plan should be established. Therefore, this study analyzed the flow of cold air at night through the KLAM_21 model in Suwon-si, Gyeonggi-do, to prepare the basic data required to apply the wind corridors. As a result, it turned out that cold air of Suwon-si was mainly generated from Gwanggyo Mountain that is a large mountain area in the north, and flowed into the urbanization promotion area, and about three hours after sunset, cold air flowed into the downtown. By district, the depth, wind speed, and direction of the cold air layer were formed differently according to the characteristics of the topography and land use. In the areas where large forests were adjacent, the flow of cold air was active. There are three main wind corridors where cold air flows to the downtown of Suwon-si, all of which are formed around rivers. Especially, if the connection between rivers and the surrounding green areas is high, the effect of wind corridors is found to be significant. In order to utilize the wind corridors of Suwon-si, based on the results of this study, it is necessary to make climate maps through actual survey and complex analysis of cold air flow and establish mid-to-long-term plans for the conservation and expansion of major wind corridors.

Hydrogeochemical Research on the Characteristic of Chemical Weathering in a Granitic Gatchment (水文化學的 資料를 통한 花崗岩質 流域의 化學的 風化特性에 關한 硏究)

  • Park, Soo-Jin
    • Journal of the Korean Geographical Society
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    • v.28 no.1
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    • pp.1-15
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    • 1993
  • This research aims to investigate some respects of chemical weathering processes, espcially the amount of solute leaching, formation of clay minerals, and the chemical weathering rate of granite rocks under present climatic conditions. For this purpose, I investigated geochemical mass balance in a small catchment and the mineralogical composition of weathered bedrocks including clay mineral assemblages at four res-pective sites along one slope. The geochemical mass blance for major elements of rock forming minerals was calculated from precipitation and streamwater data which are measured every week for one year. The study area is a climatically and litholo-gically homogeneous small catchment($3.62Km^2$)in Anyang-shi, Kyounggi-do, Korea. The be-drock of this area id Anyang Granite which is composed of coarse-giained, pink-colored miner-als. Main rock forming minerals are quartz, K-Feldspar, albite, and muscovite. One of the chracteristics of this granite rock is that its amount of Ca and Mg is much lower than other granite rock. The leaching pattern in the weathering profiles is in close reltion to the geochemical mass balance. Therefore the removal or accumulation of dissolved materials shows weathering patterns of granite in the Korean peninsula. Oversupplied ions into the drainage basin were $H^+$, $K^+$, Fe, and Mn, whereas $Na^2+$, $Mg^2+$, $Ca^2+$, Si, Al and $HCO-3^{-}$ were removed from the basin by the stream. The consumption of hydrogen ion in the catchment implies the hydrolysis of minerals. The surplus of $K^+$ reflects that vegetation is in the aggravation stage, and the nutrient cycle of the forest in study area did not reach a stable state. And it can be also presumed that the accumulation of $K^+$ in the top soil is related to the surplus of $K^+$. Oversupplied Fe and Mn were presumed to accumulate in soil by forming metallic oxide and hydroxide. In the opposite, the removal of $Na^+$, Si, Al resulted from the chemical weathering of albite and biotite, and the amount of removal of $Na^+$, Si, Al reflected the weathering rate of the bedrock. But $Ca^2+$ and $Mg^2+$ in stream water were contaminated by the scattered calcareous structures over the surface. Kaolinite is a stable clay mineral under the present environment by the thermodynamical analysis of the hydrogeochemical data and Tardy's Re value. But this result was quite different from the real assemblage of clay miner-als in soil and weathered bedrock. This differ-ence can be explained by the microenvironment in the weathering profile and the seasonal variation of climatic factors. There are different clay forming environments in the stydy area and these differences originate from the seasonal variation of climate, especially the flushing rate in the weathering profile. As it can be known from the results of the analysis of thermodynamic stability and characteristics of geochemical mas balance, the climate during winter and fall, when it is characterized by the low flushing rate and high solute influx, shows the environmental characteristics to from 2:1 clay minerals, such as illite, smectite, vermiculite and mixed layer clay minerals which are formed by neoformation or transformation from the primary or secondary minerals. During the summer and spring periods, kaoli-nite is a stable forming mineral. However it should consider that the other clay minerals can transformed into kaolinite or other clay minerals, because these periods have a high flushing rte and temperature. Materials which are directly regulated by chemical weathering in the weathered bedrock are $Na^+$, Si, and Al. The leaching of Al is, however, highly restricted and used to form a clay mineral, and that of Si falls under the same category. $Na^+$ is not taked up by growing veget ation, and fixed in the weathering profile by forming secondary minerals. Therefore the budget of $Na^+$ is a good indicator for the chemical weathering rate in the study area. The amount of chemical weathering of granite rocks was about 31.31g/$m^2+$/year based on $Na^+$ estimation.

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Study on the Fire Risk Prediction Assessment due to Deterioration contact of combustible cables in Underground Common Utility Tunnels (지하공동구내 가연성케이블의 열화접촉으로 인한 화재위험성 예측평가)

  • Ko, Jaesun
    • Journal of the Society of Disaster Information
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    • v.11 no.1
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    • pp.135-147
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    • 2015
  • Recent underground common utility tunnels are underground facilities for jointly accommodating more than 2 kinds of air-conditioning and heating facilities, vacuum dust collector, information processing cables as well as electricity, telecommunications, waterworks, city gas, sewerage system required when citizens live their daily lives and facilities responsible for the central function of the country but it is difficult to cope with fire accidents quickly and hard to enter into common utility tunnels to extinguish a fire due to toxic gases and smoke generated when various cables are burnt. Thus, in the event of a fire, not only the nerve center of the country is paralyzed such as significant property damage and loss of communication etc. but citizen inconveniences are caused. Therefore, noticing that most fires break out by a short circuit due to electrical works and degradation contact due to combustible cables as the main causes of fires in domestic and foreign common utility tunnels fire cases that have occurred so far, the purpose of this paper is to scientifically analyze the behavior of a fire by producing the model of actual common utility tunnels and reproducing the fire. A fire experiment was conducted in a state that line type fixed temperature detector, fire door, connection deluge set and ventilation equipment are installed in underground common utility tunnels and transmission power distribution cables are coated with fire proof paints in a certain section and heating pipes are fire proof covered. As a result, in the case of Type II, the maximum temperature was measured as $932^{\circ}C$ and line type fixed temperature detector displayed the fire location exactly in the receiver at a constant temperature. And transmission power distribution cables painted with fire proof paints in a certain section, the case of Type III, were found not to be fire resistant and fire proof covered heating pipes to be fire resistant for about 30 minutes. Also, fire simulation was carried out by entering fire load during a real fire test and as a result, the maximum temperature is $943^{\circ}C$, almost identical with $932^{\circ}C$ during a real fire test. Therefore, it is considered that fire behaviour can be predicted by conducting fire simulation only with common utility tunnels fire load and result values of heat release rate, height of the smoke layer, concentration of O2, CO, CO2 etc. obtained by simulation are determined to be applied as the values during a real fire experiment. In the future, it is expected that more reliable information on domestic underground common utility tunnels fire accidents can be provided and it will contribute to construction and maintenance repair effectively and systematically by analyzing and accumulating experimental data on domestic underground common utility tunnels fire accidents built in this study and fire cases continuously every year and complementing laws and regulations and administration manuals etc.

The Characteristics of Fishing Ground in the Adjacent Sea of Naro Island (1) - Oceanic Condition of Fishing Ground - (나로도 주변해역의 어장학적 특성 (1) - 어장의 해황 변화 -)

  • 김동수;주찬순;박주삼
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.39 no.1
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    • pp.8-18
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    • 2003
  • In order to investigate the oceanic condition of fishing ground in the adjacent sea of Naro Island, the oceanographic observation were carried out by the training vessel of Yosu National University on winter, spring, summer, and autumn in 2000. Main features in the observation are as follows; 1) the ranges of temperature, salinity, and chlorophyll-a were from 4.$3\circ_C$ to 10.$1\circ_C$, from 33.1 psu to 34.9 psu, and from 0.1 $ug$/$\Omega$ to 26.2 $ug$/$\Omega$ in winter, from 8.$1\circ_C$ to 13.$7\circ_C$, from 33.1 psu to 34.3 psu, and from 0.1 $ug$/$\Omega$ to 24.4 $ug$/$\Omega$ in spring, from 14.$5\circ_C$ to 24.$2\circ_C$, from 30.5 psu to 34.1 psu, and from 0.1 $ug$/$\Omega$ to 30.0 $ug$/$\Omega$ in summer, and from 14.$8\circ_C$ to 18.$6\circ_C$, from 30.1 psu to 34.0 psu, and from 0.1 $ug$/$\Omega$ to 19.1 $ug$/$\Omega$ in autumn, respectively, 2) the temperature in the coastal region was higher than that in the open ocean while salinity was lower, and the convection was identified between the surface and the bottom during in winter and autumn, and the thermocline were made between surface and 20m layer with vertical gradients of 4.$0\circ_C$/7m in summer, 3) the chlorophyll-a in the this region was varied in each season, being highly distributed in spring, on bottom and coastal region, and 4) an evidence of sea water intrusion toward Sori Island was observed, and of inner water intrusion from Yeoja Bay was observed.

Studies on the Desalinization and Improvement of Physical-chemical Characteristics of Saline and Alkali Soils by CHP Treatment (CHP에 의(依)한 간척지(干拓地) 토양(土壤)의 제염(除鹽) 및 이화학성질개량(理化學性質改良)에 관(關)한 시험연구(試驗硏究))

  • Lee, S.H.;Oh, J.S.;Im, C.N.
    • Applied Biological Chemistry
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    • v.8
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    • pp.65-73
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    • 1967
  • For the study of method for salt elimination aimed at reforming tidal land into normal paddy fields in a short period with reduction of periods requiring for elimination of saline, CHP (a kind of Ca-hum ate), a soil conditioner made of peat as a main material was tried. In the pot experiment, effect on elimination of salt, improvement of physical-chemical characteristics and rice cultivation test were studied. The results of these tests are as follows: 1, CHP treatment somewhat improves aggregation state with some effect on aggregation. 2. CHP treatment is remarkably effective in permeability which increases with 1.0 percent treatment by three times in percolation rate, and by 4.5 times in volume of leached water respectively. 3. With the increase of CHP amounts, salt was eliminated in short period. When 80% of the total Na was leached in 1.0% CHP-A treated pot, control pot begins permeable. 4. CEC and phosphorous absorption capacity are not influenced by CHP treatment. 5. Growing state of rice is greatly influenced by rainfalls. Growth of rice in tidal land however are almost similar to those in normal paddy fields with layer amounts of CHP treatment. With salt content in the soils, saline hazard and numbers of ineffective stems, amounts of unmatured grain are increased. 6. With the treatment of CHP yields of rough rice were increased. With 0.5% CHP treatment the yields were similar to those of the normal paddy fields. With 1.0% CHP-A treatment, the yields were increased by 15 times more than those of none treated soil and by 25 percent more than normal paddy soils.

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Ni/Au Electroless Plating for Solder Bump Formation in Flip Chip (Flip Chip의 Solder Bump 형성을 위한 Ni/Au 무전해 도금 공정 연구)

  • Jo, Min-Gyo;O, Mu-Hyeong;Lee, Won-Hae;Park, Jong-Wan
    • Korean Journal of Materials Research
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    • v.6 no.7
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    • pp.700-708
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    • 1996
  • Electroless plating technique was utilized to flip chip bonding to improve surface mount characteristics. Each step of plating procedure was studied in terms pf pH, plating temperature and plating time. Al patterned 4 inch Si wafers were used as substrstes and zincate was used as an activation solution. Heat treatment was carried out for all the specimens in the temperature range from room temperature to $400^{\circ}C$ for $30^{\circ}C$ minutes in a vacuum furnace. Homogeneous distribution of Zn particles of size was obtained by the zincate treatment with pH 13 ~ 13.5, solution concentration of 15 ~ 25% at room temperature. The plating rates for both Ni-P and Au electroless plating steps increased with increasing the plating temperature and pH. The main crystallization planes of the plated Au were found to be (111) a pH 7 and (200) and (111) at pH 9 independent of the annealing temperature.

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