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Boulangerite from the Janggun Mine, Republic of Korea; Contributions to the Knowledge of Ore-Forming Minerals in the Janggun Lead-Zinc-Silver Ores (2) (한국·장군광산산 보울란저라이트에 대하여; 장군 연·아연·은 구성광물의 지식에 대한 기여 (2))

  • Lee, Hyun Koo;Imai, Naoya
    • Economic and Environmental Geology
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    • v.26 no.2
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    • pp.129-134
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    • 1993
  • At the Janggun mine, boulangerite usually occurs as needles or irregularly-shaped grains, up to $500{{\mu}m}$ in longer dimensions, closely associated with galena, minerals of a tetrahedrite-freibergite series and bournonite in the peripheries of South A and B orebodies and the zone of manganoan carbonates surrounding them. In some places, especially at the top of South B orebody, it occures as "feather ore" consisting of its fine needles or "hairs" in small drusy cavities together with fine-grained euhedral galena, pyrite, manganoan carbonates, quartz, etc. In reflected light, it is bluish grey in colour exhibiting moderate bireflectance and is strongly anisotropic without any internal reflections. Reflectance in air is $R_{max}=43.2$, $R_{min}=35.7$ percent at wavelength of 580 nm, and VHN: $146-173\;kg/mm^2$ at a 50 g-load. The chemical composition on the average from 23 complete spot analyses by electron microprobe is, Pb 56.1, Sb 25.1, S 18.5, Total 99.6 (all in weight percent); the corresponding chemical formula calculated on the basis of S=11 is; $Pb_{5.16}Sb_{3.93}S_{11.0}$ which fulfils approximately the ideal formula $Pb_5Sb_4S_{11}$. The strongest reflections on the X-ray diffraction pattern are; $3.73\;{\AA}\;(10)$, $3.22\;{\AA}\;(5)$, $3.03\;{\AA}\;(4)$ and $2.82\;{\AA}\;(5)$ and the pattern is in harmonic with space group $C^5_{2h}-P2_1/a$. From the textural evidence of the microscopic observations, the mineral is considered to have been formed at the latest stage of hydrothermal lead-zinc-silver mineralization.

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한국수출산업을 위한 산업디자인 개선에 관한 연구 -시각.공예.제품디자인을 중심으로-

  • 박대순
    • Archives of design research
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    • v.1 no.1
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    • pp.1-162
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    • 1980
  • The Design Society of Korea. It is our urgent task that we should map out our detailed guiedlines for the improvement of export-oriented industries and of the design of export goods in preparation for our export goal of $30 billion in the upcoming 1980s. The government, university design researchers, and most entrepreneurs have confronted diverse kinds of racking issues: how much do most export industries take advantage of the indus-trial design for the improvement of the quality of export goods\ulcorner, structural defects of most export industries, chronic and vicious cycle of overlooking the value of the industrial design in the process of manufacturing export goods and etc. In other words, the recent trend of slighting the industrial design is to speed up the sales of only unsophisticated goods on the international markets. Although Koreans have been plagued by scantiness of natural resources under these circumstances, most Korean people have showed off their strong will for today's growth. Furthermore, most exporters should do their best to sweep overseas markets by manufacturing sophisticated goods outranking those commodi-ties made by the United States, Japan, West Germany and the other developed countries. In this respect, we have to make our best efforts for the expensive application and practical use of the industrial design, one of the comprehensive sciences, in the face of the hard realities and conditions which we have confronted until now. For example, it can be attributed to the practical application of the industrial design that the neighboring Japan, West Germany, France, the United Kingdom in Europe, and the United States in North America have formulated a highly advan-ced cultural zone and braced up for their own trade protection-ism and tightened their embargoes on EEC goods. Unless any export goods take the best advantage of the industrial design, one of the behavioral sciences capable of satisfying the material mental needs of modern men and of promoting cultural growth, I am convinced that they will not infiltrate into any countries that have enjoyed their own highly cultural lives. It is absolutely important that most Korean universities, state-run, private corporations and research institutes should work out the improvement strategy for the development and practical use of the industrial design as will as the revision of the present curricula of the departments of design. However, most design researchers have come to grips with several difficult problems such as the correlation of export oriented industries and the industrial design and the development of the design of export goods. The improvement of the industrial design is our urgent assignment that we have to solve in the 1980s. Accordimgly, I cannot too much emphasize the value the recognition of the industrial design in our industrial communities because we have never witnessed the prosperity of those countries which have taken little notice of the importance of the industrial design. Hopefully, most entrepreneurs will take much consideration of the value of the industrial design and then can defeat their rival businessmen on the international markets by exporting goods of highly sophisticated design. In this respect, the main purpose of the research paper which this society presented is to underline the fact that the improvement and development of the industrial design is our common assignment to be studied from the viewpoints of national dimension as well as in conformity with our immediate goal for the export-oriented prosperity of state. In conclusion, I would like to highlight the fact that our export goods shall be continually developed in pace with the correlative improvement of the indudtrial design so as to pave the way for their bright prospect and to enhance their best impression of the first-class goods on the international markets.

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A Study on Luxury Prohibition of Korean Personal Ornaments (한국장신구의 사치 금제 고찰)

  • 추원교
    • Archives of design research
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    • v.2 no.1
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    • pp.43-62
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    • 1989
  • The luxury is the expression of human being's ornament instinct. In this study, in order to grasp the moulding system of the Korean's personal ornaments, the process of luxury prohibition was reviewed to search for to which direction the ornaments developed in the frame of the prohibited style connected closely to the character of the personal ornaments. The proiod was fixed from the old society to the late Chosun dynasty era. The beginning of the luxury in Korea seems to be the start of the luxury burial at the time of funeral in the age of Koguryo., In the era of Koguryo, 10th year of King Dongmyung (B. C. 28), in the era of Baekje, 27th year of King Koi(260), the prohibition of dress regulation and the style of dress were conducted. The prohibition of personal ornaments in Silla was started from King Bup:Heung, and in the 9th year of King Heung-Duk, the prohibition was conducted in order to correct the luxury of the nobles and set up the social discipline. In the 11 th of King Il-Sung-Ni-Sa-Kum, the use of gold, silver and jade was prohibited in the civilian circles. The prohibition of Silla was succeeded to Koryo era, and in the 7th year of King Kwangjong(956), the system of Baekgwan Gongbok(uniform for government officials) was set up, and the system of Sasek Gongbok(four color official uniform) was set up in the 11 th year of the same King, and the prohibition of the personal ornaments such as crown and band is considred to have been conducted. The prohibition of gold and silver was conducted in the first year of King Sungjong(982), and in the 4th year of King Chungryul(l260), the order of wearing the dress and hat in accordance with the Yusan dynasty and the Mongolian customs were widely circulated in the royal court and vivilian circles. The strong influence of Mongolia made the taste of the traditional personal ornaments laste. The personal ornaments were used for the nobles until the age of the Unified Sillar but even the common people could use them in case they were rich, and such a circumstances made the use of foreign goods inflated. The prohibition of Koryo era was aimed at the prohibition of the foreign goods of luxury, and the classification of the social status.In the age of Chosun Dynasty, the production of gold and silver was feeble indeed but the oute reason of the prohibition was to eradicate the luxurious tendency, elevate the custom of eradicate the luxurious tendency, elevate the custom of thrift, and moreover, the gold, silver and jade were no the products of Korea and the prohibition was conducted but the true reason was afor the tribute tt China and the classification of status. The prohibition of Chosun dynasty was conducted first in the June of the 3rd year of King Taejo The major contents of prohibition was no use of gold, silver and jade, coral, agate, amber, etc. of th, wives of the Dang-Sang-Kwan (Court Nobleman) or their sons and daughters, and the same pheno menon was common even at the time of marriage. The people engaged in the secret trade there of wert beheaded. The personal ornaments in the prohibition were the pendent trinket, Binyo (crossbar) ceremonial ornamental hat, ring, earring, ornamental knife, hat string, hat ornament, belt, etc. Thl luxurious marriage expenses out of the luxury was severe, and lose of the marriageable age because 0 non-preparing the marriage goods was the national evil. The prohibition oC luxury was hard to bt kept to the nobles or rich people, the same as old days and present days. The prohibition of th{ luxury and personal ornaments of Korea had nothing to do with the commons, and it was limited tc the nobles and rich people. The prohibition was aimed to cultivating the custom of frugality by eradicating the luxurious atmosphere, but it was chiefly due to the tribute to the China and tht discrimination of the. status. We can say that the recent personal ornament was the flower of handi craft industry bloomed in the prohibition and regulation.

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Errors in Net Ecosystem Exchanges of CO2, Water Vapor, and Heat Caused by Storage Fluxes Calculated by Single-level Scalar Measurements Over a Rice Paddy (단일 높이에서 관측된 저장 플럭스를 사용할 때 발생하는 논의 이산화탄소, 수증기, 현열의 순생태계교환량 오차)

  • Moon, Minkyu;Kang, Minseok;Thakuri, Bindu Malla;Lee, Jung-Hoon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.17 no.3
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    • pp.227-235
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    • 2015
  • Using eddy covariance method, net ecosystem exchange (NEE) of $CO_2$ ($F_{CO_2}$), $H_2O$ (LE), and sensible heat (H) can be approximated as the sum of eddy flux ($F_c$) and storage flux term ($F_s$). Depending on strength and distribution of sink/source of scalars and magnitude of vertical turbulence mixing, the rates of changes in scalars are different with height. In order to calculate $F_s$ accurately, the differences should be considered using scalar profile measurement. However, most of flux sites for agricultural lands in Asia do not operate profile system and estimate $F_s$ using single-level scalars from eddy covariance system under the assumption that the rates of changes in scalars are constant regardless of the height. In this study, we measured $F_c$ and $F_s$ of $CO_2$, $H_2O$, and air temperature ($T_a$) using eddy covariance and profile system (i.e., the multi-level measurement system in scalars from eddy covariance measurement height to the land surface) at the Chengmicheon farmland site in Korea (CFK) in order to quantify the differences between $F_s$ calculated by single-level measurements ($F_s_{-single}$ i.e., $F_s$ from scalars measured by profile system only at eddy covariance system measurement height) and $F_s$ calculated by profile measurements and verify the errors of NEE caused by $F_s_{-single}$. The rate of change in $CO_2$, $H_2O$, and Ta were varied with height depending on the magnitudes and distribution of sink and source and the stability in the atmospheric boundary layer. Thus, $F_s_{-single}$ underestimated or overestimated $F_s$ (especially 21% underestimation in $F_s$ of $CO_2$ around sunrise and sunset (0430-0800 h and 1630-2000 h)). For $F_{CO_2}$, the errors in $F_s_{-single}$ generated 3% and 2% underestimation of $F_{CO_2}$ during nighttime (2030-0400 h) and around sunrise and sunset, respectively. In the process of nighttime correction and partitioning of $F_{CO_2}$, these differences would cause an underestimation in carbon balance at the rice paddy. In contrast, there were little differences at the errors in LE and H caused by the error in $F_s_{-single}$, irrespective of time.

Complex Terrain and Ecological Heterogeneity (TERRECO): Evaluating Ecosystem Services in Production Versus water Quantity/quality in Mountainous Landscapes (산지복잡지형과 생태적 비균질성: 산지경관의 생산성과 수자원/수질에 관한 생태계 서비스 평가)

  • Kang, Sin-Kyu;Tenhunen, John
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.12 no.4
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    • pp.307-316
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    • 2010
  • Complex terrain refers to irregular surface properties of the earth that influence gradients in climate, lateral transfer of materials, landscape distribution in soils properties, habitat selection of organisms, and via human preferences, the patterning in development of land use. Complex terrain of mountainous areas represents ca. 20% of the Earth's terrestrial surface; and such regions provide fresh water to at least half of humankind. Most major river systems originate in such terrain, and their resources are often associated with socio-economic competition and political disputes. The goals of the TERRECO-IRTG focus on building a bridge between ecosystem understanding in complex terrain and spatial assessments of ecosystem performance with respect to derived ecosystem services. More specifically, a coordinated assessment framework will be developed from landscape to regional scale applications to quantify trade-offs and will be applied to determine how shifts in climate and land use in complex terrain influence naturally derived ecosystem services. Within the scope of TERRECO, the abiotic and biotic studies of water yield and quality, production and biodiversity, soil processing of materials and trace gas emissions in complex terrain are merged. There is a need to quantitatively understand 1) the ecosystem services derived in regions of complex terrain, 2) the process regulation occurred to maintain those services, and 3) the sensitivities defining thresholds critical in stability of these systems. The TERRECO-IRTG is dedicated to joint study of ecosystems in complex terrain from landscape to regional scales. Our objectives are to reveal the spatial patterns in driving variables of essential ecosystem processes involved in ecosystem services of complex terrain region and hence, to evaluate the resulting ecosystem services, and further to provide new tools for understanding and managing such areas.

Analysis of Reproductive and Growing Performances by Sow Farm Sizes (국내 양돈장의 모돈규모별 번식 및 육성성적 분석)

  • Kim, Gye Woong;Ok, Young Soo
    • Reproductive and Developmental Biology
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    • v.39 no.1
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    • pp.23-28
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    • 2015
  • This study was carried out to investigate the reproductive and growing performances in sow farms located in Chungnam. Data collected from a total of 15 sow farms divided into 3 farm groups for 1 year were analyzed. The results obtained were as follows; The average of sow at small and large farms were 114.25 and 487.88 heads, respectively. And then, the difference among 3 groups in sow farm was not found significantly in farrowing rate. The significant difference among 3 farm groups was significantly found(p<0.05) in total litter size. The litter size born alive at sucking in small sow farm and middle farms were 9.93, and 10.48 pigs. The difference between small and large farms in number of pigs at weaning were significantly shown 8.89, and 9.35 pigs(p<0.05), respectively. The difference among 3 sow farms for ages at weaning showed significantly (p<0.05). The cycles of farrowing rate per year in small, large and middle farms were 2.17, 2.23 and 2.32, respectively. The significant difference among 3 sow groups was found in farrowing rate(p<0.05). The growing rate up to weaning for middle farms was significantly the higher level(94.70%) than that for other farms(p<0.05). The differences among 3 farm groups for marketing weight were not significantly shown.

The Solvent Extraction of Univalent Cation Picrates by New Podands (새로운 포단드에 의한 피크린산 일가 양이온 염의 용매추출)

  • Jung, Jong Hwa;Cho, Sung Bae;Kim, Jineun;Kim, Jae Sang;Lee, Shim Sung
    • Analytical Science and Technology
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    • v.6 no.1
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    • pp.29-37
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    • 1993
  • Some new podands containing phenyl(B), benzyl(Bz), pyridine(Py), quinoline(Q) and naphthalene(Np) as end-groups, and oxygen(O) and sulfur(S) in ether chains as donor atoms have been synthesized. The univalent cation binding characteristics of these podands have been studied by NMR titration and solvent extraction. By NMR titration we have found that the most of podands form 1:1 complexes with $Ag^+$ ion. Especially, the substituted sulfur atoms in ether chains show the effects to enhance the stabilities. We also carried out the extractions of univalent cation picrates including alkaline metal, $Ag^+$, $Tl^+$ and $NH_4{^-}$ ions from aqueous to chloroform layer by using these podands. We found that the extractabilities of $Ag^+$ ion with the quinoline-containing podands such as, $Q_2O_4$, $Q_2O_5$ and $BQO_5$ were 86.8, 86.6 and 48.0% respectively, but the naphthalene-containing podands such as, $Np_2O_4$ and $Np_2O_5$ extracted quite small amount. Otherwise, in cases of $Bz_2O_3S_2$(89.4%), $B_2O_2S_2$(96.8%), $B_2O_3S_2$(58.9%), $Py_2O_2S_2$(58.8%), $Py_2O_3S_2$(42.1%), and $B_2O_4S$(15.0%), interestingly, $Bz_2O_3S_2$ which have sulfur atoms and benzyl groups showed the highest extraction selectivity for $Ag^+$ ion. This result seems due to not only the strong interaction of $Ag^+$ ion with sulfur donors according to the HSAB theory, but also the effective ${\pi}-{\pi}$ stacking interaction between two aromatic end-groups which is enhanced by the flexible methylene spacing group in benzyl groups instead of phenyl groups. The extraction coefficients gave the similar tendency as the extractabilities and the stabilities. From these results, it could be concluded that the predominant factor affected to extraction coefficients is the stabilities, which are strongly influenced by the structures of podands.

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Studies on Partition and Extraction Equilibria of Metal-Dithiocarbamate Complexes(II). Metal Complexes of Ammonium Pyrrolidine Dithiocarbamate (Dithiocarbamate 금속착물의 분배 및 추출평형(제2보). Ammonium Pyrrolidine Dithiocarbamate의 금속착물)

  • Lee, Jong-Sun;Choi, Jong-Moon;Choi, Hee-Seon;Kim, Young-Sang
    • Analytical Science and Technology
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    • v.8 no.3
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    • pp.321-334
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    • 1995
  • Basic studies for the effective extraction of ammonium pyrrolidine dithiocarbamate(APDC) complexes of Co(II), Ni(II) and Cu(II) into a solvent have been performed. The maximum distribution ratio was appeared (log D=1.3543) at pH 2.0 and the partition coefficient was 2.489 in the extraction of $4{\times}10^{-5}M$ APDC itself into chloroform. From the UV/visible spectra of metal-chelates in aqueous and organic solutions, the pH to form stable 1:2 metal-ligand complexes were Co(II):5.0, Ni(II):8.0 and Cu(II):8.0, respectively and only 1 minute was enough to be partitioned into the chloroform. Besides, the partition and extraction equilibria of the complexes were investigated by back-extracting $10.0{\mu}g/ml$ metal-chelates from the solvent into an aqueous solution beacuse of their slight solubilities in the aqueous solution. The distribution coefficients and extractabilities were as follows : at pH 6.5~8.5 of the aqueous solution, log D=2.834 : E(%)=99.9% for $Co(PDC)_2$, at pH 11, log D=5.699 E%=100 for $Ni( PDC)_2$, and at pH 6.0, log D=2.025 : E(%)=99.1% for $Cu(PDC)_2$. And the extraction and formation constants were log $K_{ex}=9.671$ : log ${\beta}_2=6.938$ for $Co(PDC)_2$, log $K_{ex}=9.646$ : log ${\beta}_2=7.071$ for $Ni( PDC)_2$, and log $K_{ex}=9.074$ : log ${\beta}_2=7.049$ for $Cu(PDC)_2$, respectively. From these results, an optimum extraction procedure can be constructed for the separative concentration of trace metallic ions, and the quantitative determination of them in advanced materials and environmental samples will be expected without any influence of sample matrixes.

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Analysis and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in seafood from oil contaminated bay (유류 오염지역의 수산물 중 다환방향족탄화수소류 (PAHs) 분석 및 위해평가)

  • Jeong, Ji-Yoon;Choi, Chan-Woong;Ryeom, Tai-Kyung;Cho, Kyoung-Hee;Park, Se-Ryung;Shin, Ho-Sang;Lee, Kwang-Ho;Lee, Hyo-Min
    • Analytical Science and Technology
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    • v.23 no.2
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    • pp.187-195
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    • 2010
  • To assess health risk for the intake among residents after the Hebei Spirit oil spill, 16 Polycyclic Aromatic Hydrocarbons (PAHs) in seafood samples from oil contaminated bay were determined by Gas Chromatography-Mass Spectrometry (GC-MSD) and samples were personally collected and purchased by residents. Samples were hydrolyzed with KOH and extracted with methylene chloride. The extracted solution were cleaned up using silica/florisil column and 16 PAHs were eluted by methylene chloride : n-hexane (1:9) mixture and determined by GC-MSD in Selected Ion Monitoring (SIM) mode. The mean recoveries for 16 PAHs ranged from 79% to 85%. The 16 PAHs levels in 126 samples ranged from 0.17 to $6.04\;{\mu}g$/kg and the TEQBaP (Toxic EQuivalents) levels in 126 samples were calculated using benzo(a)pyrene toxic equivalency factor for individual 16 PAHs and ranged from 0 to $0.91\;{\mu}gTEQ$/kg. The average Benzo(a)pyrene dietary exposure of residents was $5.5{\times}10^{-8}\;mg/kg$ bw/day and the average PAHs chronic dietary exposure was $1.3{\times}10^{-5}\;mg$ TEQ/kg bw/day. The margin of exposure (MOE) and the excess cancer risk and were $1.8{\times}10^6$ and $9.8{\times}10^{-8}$, respectively. Therefore, the assessment result was considered as low concern for health risk.

Effects of Feeding Type of Concentrates During Growing Period and Slaughter Age on Growth Performance, Feed Efficiency and Carcass Characteristics in Growing-Fattening Holstein Steers (홀스타인 거세우에 대한 육성기 농후사료 급여형태 및 출하월령이 성장발육, 사료이용성 및 도체특성에 미치는 효과)

  • Kang, S.W.;Jeong, H.Y.;Ahn, B.S.;Oh, Y.K.;Son, Y.S.
    • Journal of Animal Science and Technology
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    • v.46 no.6
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    • pp.989-998
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    • 2004
  • The objectives of this work was to investigate the effects of feeding type of concentrates during growing period and slaughter age on growth performance, feed efficiency and carcass characteristics in growing-fattening Holstein steers. Treatments were two concentrates feeding types(ad libitum or restricted 1.9% of BW) and three slaughter ages(at 19, 22 or 25 mo). Body weight at slaughter was numerically higher(approx. 8.3%) for the restricted than the ad libitum feeding groups. TDN intake rate was higher(8.4%) for the restricted than the ad libitum feeding groups. One mo slaughter delay increased TDN intake by 4%. Despite the lack of significances, higher back fat thickness and rib-eye area appeared in the restricted feeding or the late slaughter groups compared with the ad libitum feeding or the early slaughter groups. Marbling score(mean 2.46) numerically increased when the steers were restrictively fed concentrates compared with the ad libitum feeding groups. In addition, significant increases in the marbling score were associated with the slaughter age delay. In economic analysis, increases in total income were associated with the restricted feeding and the slaughter age delay. Whereas the highest monthly income appeared in the restricted feeding-and-slaughter at 22 mo group. In conclusion, the optimal feeding system may be 1) the restricted concentrates feeding(1.9% of BW) during growing period and 2) the late slaughter age(22${\sim}$25 mo of age) in growing-fattening Holstein steers fed rice straw.