• 한국환경과학회지
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• 제18권7호
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• pp.735-746
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• 2009

Hydrochloric acid salt of a new $N_2O_3$ pentadentate ligand, N,N'-Bis(2-Hydroxybenzyl)-1,3-diamino-2-propanol(H-BHDP 2HCl) was synthesized. Br-BHDP 2HCl, CI-BHDP 2HCl, $CH_3-BHDP$ 2HCl and $CH_3O$-BHDP 2HCl having Br, Cl, $CH_3$ and $CH_3O$ substituents at 5-position of the phenol group of H-BHDP 2HCl were also synthesized. The potentiometry study in aqueous solution revealed that the proton dissociations of the synthesized ligands occurred in four steps and their order of the calculated overall proton dissociation constants($log{\beta}_p$) was Br-BHDP < Cl-BHDP < H-BHDP < $CH_3O-BHDP$ < $CH_3-BHDP$. The order showed a similar trend to that of Hammett substituent constants(${\delta}_p$). The order of the stability constants($logK_{ML}$) was Co(II) < Ni(II) < Cu(II) < Zn(II) < Cd(II) < Pb(II). The order in their stability constants ($logK_{ML}$) of each transition metal complex agreed with that of the overall proton dissociation constants ($log{\beta}_p$).

• 자원환경지질
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• 제38권6호
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• pp.657-662
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• 2005

Extractions fro fertilizer and soil samples were performed to yield the operationally defined fractions 'soluble' chromate (extractable with $NH_4NO_3$), 'exchangeable' chromate (extractable with phosphate buffer pH 7.2), and these results were compared with the data obtained by extractions with ammonium sulfate, borate buffer pH 7.2, saturated borax pH 9.6, and polyphosphate (Graham's salt). In order to maintain the pH of extractant solution about constant, the concentration of extractant buffer had to be raised to at least 0.5 M. The results strongly depended on the kind of extractant, and the solid: liquid ratio. For most of the samples investigated, the extraction efficiency increased in the order borate-sulfate-nitrate-phosphate. Whereas the recovery of $K_2CrO_4\;and\;CaCrO_4$ added to the samples of basic slags prior to the extraction was about complete, the recovery of added $PbCrO_4$ was highly variable. In soil extracts, the color reaction was interfered from co-extracted humics, which react with the chromate in weak acid solution during the time period necessary for color reaction (1 hour). However, this problem can be overcome by standard addition and subtraction of the color of the extractant solution. In soil extract of about pH < 7, organic material reduced chromate during the extraction period also, and standard addition of soluble chromate is recommended to prove recovery and the stability of chromate in the samples. In admixtures of soils and basic slags, results for hexavalent chromium were lower than from the mere basic slags. This effect was more pronounced in phosphate than in nitrate extracts. As a proficiency test, samples low in organic carbon from contaminated sites in Hungary were tested. The results from $NH_4NO_3$ extracts satisfactorily matched the results of the Hungarian labs obtained from $CalCl_2$ extractants.

• 한국대기환경학회지
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• 제19권6호
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• pp.701-717
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• 2003

The objective of this study was to extensively estimate the air quality trends of the study area by surveying con-centration trends in months or seasons, after analyzing the mass concentration of PM-10 samples and the inorganic lements, ion, and total carbon in PM-10. Also, the study introduced to apply the PMF (Positive Matrix Factoriza-tion) model that is useful when absence of the source profile. Thus the model was thought to be suitable in Korea that often has few information about pollution sources. After obtaining results from the PMF modeling, the existing sources at the study area were qualitatively identified The PM-10 particles collected on quartz fiber filters by a PM-10 high-vol air sampler for 3 years (Mar. 1999∼Dec.2001) in Kyung Hee University. The 25 chemical species (Al, Mn, Ti, V, Cr, Fe, Ni, Cu, Zn, As, Se, Cd, Ba, Ce, Pb, Si, N $a^{#}$, N $H_4$$^{+}$, $K^{+}$, $Mg^{2+}$, $Ca^{2+}$, C $l^{[-10]}$ , N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$, TC) were analyzed by ICP-AES, IC, and EA after executing proper pre - treatments of each sample filter. The PMF model was intensively applied to estimate the quantitative contribution of air pollution sources based on the chemical information (128 samples and 25 chemical species). Through a case study of the PMF modeling for the PM-10 aerosols. the total of 11 factors were determined. The multiple linear regression analysis between the observed PM-10 mass concentration and the estimated G matrix had been performed following the FPEAK test. Finally the regression analysis provided source profiles (scaled F matrix). So, 11 sources were qualitatively identified, such as secondary aerosol related source, soil related source, waste incineration source, field burning source, fossil fuel combustion source, industry related source, motor vehicle source, oil/coal combustion source, non-ferrous metal source, and aged sea- salt source, respectively.ively.y.

• 한국해양공학회지
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• 제24권5호
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• pp.60-66
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• 2010

Zinc has a number of characteristics that make it well suited for use as a coating to protecting iron and steel products from corrosion. Its excellent corrosion resistance in most environments accounts for its successful use as a protective coating on a variety of products and in many exposure conditions. The excellent field performance of zinc coatings results from their ability to form dense, adherent films that corrode at a rate that ranges from 1% to 10% of the corrosion rate of ferrous materials, depending on the environment. Recently, EU RoHS and EU ELV prohibited the use of materials that adversely affect the environment, such as Pb, Hg, Cd, and $Cr^{+6}$. In this study, environmentally-friendly, Cr-free solutions (epoxy solution, acrylic solution, and urethane solution S-700) and organic/inorganic solution with Si; LRO-317) were used to evaluate the corrosion resistance of zinc-coated steel subjected to a saltwater spray for 72 hours. The coating of urethane solution (S-700) was best among the three kinds of solution with heat treatment during five minutes at $190^{\circ}F$. Test specimens with S-700 and LRO-317 coating were heat treated in a drying oven at 170, 180, 190, 200, and $210^{\circ}C$ for five minutes. The results show that the optimum corrosion resistance was $190^{\circ}C$ in EGI and $170^{\circ}C$ in HDGI, respectively.

• Asian Journal of Atmospheric Environment
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• 제7권4호
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• pp.217-226
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• 2013

The collection of TSP and $PM_{2.5}$ aerosols has been made at the Gosan Site of Jeju Island during 2008-2011, and their ionic and elemental species were analyzed, in order to examine the seasonal variation and characteristics of aerosol compositions. The anthropogenic components ($NH_4{^+}$, $nss-SO_4{^{2-}}$, $NO_3{^-}$, S, Zn, Pb) and the soil components ($nss-Ca^{2+}$, Al, Fe, Ca) showed high concentrations in spring as the prevailing westerly wind, but the concentrations of the sea-salt components ($Na^+$, $Cl^-$) were high in winter. In TSP, the neutralization by $NH_3$ increased in summer, but the neutralization by $CaCO_3$ increased in spring and fall seasons. The organic acids ($HCOO^-$, $CH_3COO^-$) contributed to the acidification of the aerosols by only 5.0%, so the acidification could be mostly contributed by the inorganic acids ($SO_4{^{2-}}$, $NO_3{^-}$). From the examination of the source origins by factor analysis, the compositions of TSP were influenced by the order of soil > anthropogenic > marine, on the other hand, those of $PM_{2.5}$ were by the order of anthropogenic > marine > soil. The backward trajectory analyses showed that the concentrations of $NH_4{^+}$, $nss-SO_4{^{2-}}$, $NO_3{^-}$ and $nss-Ca^{2+}$ increased highly when the air masses had moved from China continent into Gosan area of Jeju Island.

• 분석과학
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• 제23권4호
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• pp.371-382
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• 2010

제주도 고산지역에서 TSP (total suspended particulate), PM2.5 (particulate matter, below $2.5\;{\mu}m$ particle size) 대기에어로졸을 채취, 분석하여 에어로졸의 조성과 오염 특성을 조사하였다. 고산지역 대기에어로졸에서 nss(non-sea salt)-$SO_4^{2-}$과 $NH_4^+$은 다른 국내 청정지역 및 도시지역에 비해 높은 조성비를보이고 $NO_3^-$는 상대적으로 낮은 조성비를 나타내었다. 에어로졸 성분의 입경별 분포를 비교해 본 결과, 인위적 기원의 nss-$SO_4^{2-}$, $NO3_^-$, $NH_4^+$ 성분들은 대체적으로 미세입자에, 토양기원의 nss-$Ca^{2+}$과 해염기원의 $Na^+$, $Cl^-$, $Mg^{2+}$은 상대적으로 조대입자에 많이 분포하고 있는 것으로 확인되었다. 계절별로는 봄철에 nss-$Ca^{2+}$, Al, Fe, Ca, $NO_3^-$ 성분의 농도가 크게 상승하고, nss-$SO_4^{2-}$은 여름과 봄철에 높은 농도를 나타내었다. 인자분석 결과, 에어로졸은 대체적으로 인위적 발생원의 영향을 많이 받고, 다음으로 해양 및 토양 영향을 많이 받았다. 또한 역궤적 분석법으로 에어로졸 성분의 유입경로를 조사해 본 결과, nss-$SO_4^{2-}$, $NO_3^-$, Pb, nss-$Ca^{2+}$ 성분들은 대체적으로 기류가 중국대륙으로부터 제주지역으로 이동할 때 훨씬 더 높은 농도를 나타낸 반면, 북태평양에서 제주지역으로 이동할 때 상대적으로 낮은 농도를 나타내었다.

• Journal of Nutrition and Health
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• 제8권1호
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• pp.15-37
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• 1975

I. Subject of the study A study on the nutritive value and utilization of powdered seaweeds. II. Purpose and Importance of the study A. In Korea the shortage of food will be inevitable by the rapidly growing population. It will be very important study to develop a new food from the seaweeds which were not used hitherto for human consumption. B. The several kinds of seaweeds have been used by man in Korea mainly as side-dishes. However, a properly powdered seaweed will enable itself to be a good supplement or mixture to certain cereal flours. C. By adding the powdered seaweed to any cereals which have long been staple foods in this country the two fold benefits; saving of cereals and change of dietary pattern, will be secured. III. Objects and scope of the study A. Objects of the study The objects will come under four items. 1. To develop a powdered seaweed as a new food from the seaweeds which have been not used for human consumption. 2. To evaluate the nutritional quality of the products the analysis for chemical composition and animal feeding experiment will be conducted. 3. Experimental cocking and accepability test will be conducted for the powdered products to evaluate the value as food stuff. 4. Sanitary test and also economical analysis will be conducted for the powdered products. B. Scope of the study 1. Production of seaweed powders Sargassum fulvellum growing in eastern coast and Sargassum patens C.A. in southern coast were used as the material for the powders. These algae, which have been not used for human consumption, were pulverized through the processes of washing, drying, pulverization, etc. 2. Nutritional experiments a. Chemical composition Proximate components (water, protein, fat, cellulose, sugar, ash, salt), minerals (calcium, phosphorus, iron, iodine), vitamins (A, $B_1,\;B_2$ niacin, C) and amino acids were analyzed for the seaweed powders. b. Animal feeding experiment Weaning 160 rats (80 male and 80 female rats) were used as experimental animals, dividing them into 16 groups, 10 rats each group. Each group was fed for 12 weeks on cereal diet (Wheat flour, rice powder, barley powder, potato powder, corn flour) with the supplementary levels of 5%, 10%, 15%, 20% and 30% of the seaweed powder. After the feeding the growth, feed efficiency ratio, protain efficiency ratio and ,organs weights were checked and urine analysis, feces analysis and serum analysis were also conducted. 3. Experimental cooking and acceptability test a. Several basic studies were conducted to find the characteristics of the seaweed powder. b. 17 kinds of Korean dishes and 9 kinds of foreign dishes were prepared with cereal flours (wheat, rice, barley, potato, corn) with the supplementary levels of 5%, 10%, 15%, 20% and 30% of the seaweed powder. c. Acceptability test for the dishes was conducted according to plank's Form. 4. Sanitary test The heavy metals (Cd, Pb, As, Hg) in the seaweed powders were determined. 5. Economical analysis The retail price of the seaweed powder was compared with those of other cereals in the market. And also economical analysis was made from the nutritional point of view, calculating the body weight gained in grams per unit price of each feeding diet. IV. Results of the study and the suggestion for application A. Chemical composition 1. There is no any big difference in proximate components between powders of Sargassum fulvellum in eastern coast and Sargassum patens C.A. in southern coast. Seasonal difference is also not significant. Higher levels of protein, cellulose, ash and salt were found in the powders compared with common cereal foods. 2. The levels of calcium (Ca) and iron (Fe) in the powders were significantly higher than common cereal foods and also rich in iodine (I). Existence of vitamin A and vitamin C in the Powders is different point from cereal foods. Vitamin $B_1\;and\;B_2$ are also relatively rich in the powders.'Vitamin A in ·Sargassum fulvellum is high and the levels of some minerals and vitamins are seemed4 to be some influenced by seasons. 3. In the amino acid composition methionine, isoleucine, Iysine and valine are limiting amino acids. The protein qualities of Sargassum fulvellum and Sargassum patens C.A. are seemed to be .almost same and generally ·good. Seasonal difference in amino acid composition was found. B. Animal feeding experiment 1. The best growth was found at.10% supplemental level of the seaweed Powder and lower growth rate was shown at 30% level. 2. It was shown that 15% supplemental level of the Seaweed powder seems to fulfil, to some extent the mineral requirement of the animals. 3. No any changes were found in organs development except that, in kidney, there found decreasing in weight by increasing the supplemental level of the seaweed powder. 4. There is no any significant changes in nitrogen retention, serum cholesterol, serum calcium and urinary calcium in each supplemental level of the seaweed powder. 5. In animal feeding experiment it was concluded that $5%{\sim}15%$ levels supplementation of the seaweed powder are possible. C. Experimental cooking and acceptability test 1. The seaweed powder showed to be utilized more excellently in foreign cookings than in Korean cookings. Higher supplemental level of seaweed was passible in foreign cookings. 2. Hae-Jo-Kang and Jeon-Byung were more excellent than Song-Pyun, wheat cake, Soo-Je-Bee and wheat noodle. Hae-Je-Kang was excellent in its quality even as high as 5% supplemental level. 3. The higher levels of supplementation were used the more sticky cooking products were obtained. Song-Pyun and wheat cake were palatable and lustrous in 2% supplementation level. 4. In drop cookie the higher levels of supplementation, the more crisp product was obtained, compared with other cookies. 5. Corn cake, thin rice gruel, rice gruel and potato Jeon-Byung were more excellent in their quality than potato Man-Doo and potato noodle. Corn cake, thin rice gruel and rice gruel were excellent even as high as 5% supplementation level. 6. In several cooking Porducts some seaweed-oder was perceived in case of 3% or more levels of supplementation. This may be much diminished by the use of proper condiments. D. Sanitary test It seems that there is no any heavy metals (Cd, Pb, As, Hg) problem in these seaweed Powders in case these Powders are used as supplements to any cereal flours E. Economical analysis The price of the seaweed powder is lower than those of other cereals and that may be more lowered when mass production of the seaweed powder is made in future. The supplement of the seaweed powder to any cereals is also economical with the criterion of animal growth rate. F. It is recommended that these seaweed powders should be developed and used as supplement to any cereal flours or used as other food material. By doing so, both saving of cereals and improvement of individual's nutrition will greatly be achieved. It is also recommended that the feeding experiment for men would be conducted in future.

• 한국지하수토양환경학회지:지하수토양환경
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• 제7권1호
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• pp.53-62
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• 2002

본 연구는 쓰레기 매립지의 생태학적 복원에 필요한 토양환경자료를 제공하고자 경기도 지역의 10개 쓰레기 매립지의 복토층 토양과 주변토양의 이화학성을 조사하였다. 매립지 토양은 염류집적에 의하여 주변토양 보다 pH와 전기전도도는 높았으나, 유기물 및 전질소 함량은 낮았다. 매립지 토양은 식물체 필수성분 중 특히 질소와 인산의 함량은 낮은 것으로 나타났다. 토양의 교환성 양이온 함량은 매립지간 차이가 컸으나 매립지 토양이 주변토양에 비하여 높은 경향이었다. 토양 중 중금속 함량은 매립지 인천 원창동 매립지를 제외한 모든 매립지에서 대조구보다 높게 나타났으나 모든 매립지에서 식물에게 독성을 일으킬 수 있는 임계농도보다 낮았으며, 또한 토양환경보전법의 농경지에 대한 우려기준에 비하여 매우 낮은 값을 나타내었다. 따라서 매립지 토양은 질소와 인산의 함량이 낮으므로 자연 또는 인공적인 식생을 이용한 매립지의 생태학적 복원시 질소와 인산의 시용과 같은 토양관리 대책이 필요하다고 판단되었다.

• 한국식품과학회지
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• 제32권6호
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• pp.1442-1445
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• 2000

총 11종 소금의 식염함량은 국내산 천일염의 경우 $80.31{\sim}89.84%$, 수입산 천일염은 $91.59{\sim}97.66%$로 나타났다. 불용성분은 국내산 천일염이 $0.01{\sim}1.24%$, 수입산 천일염이 $0.06{\sim}0.89%$를 나타냈고, 황산이온함량은 $0.21{\sim}0.55%$, 수입산 천일염은 $0.18{\sim}0.31%$로 나타났다. 국내산 천일염 중 수입산에 비해 상대적으로 높게 함유된 무기질은 K 그리고 Mg이었으며 국내산과 수입산에 비슷한 수준으로 존재하는 것은 Ca이었다. Mn은 극미량 검출되었고, Cu는 수입산에서 상대적으로 높게 검출되었으며 Ge은 국내산에서 대체적으로 높게 나타났다. 국내산 및 수입산 천일염의 중금속(Pb, Cd, As 그리고 Hg)함량은 식품위생법 규정의 기준치 이하로 나타났다.

• Applied Microscopy
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• 제30권4호
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• pp.357-365
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• 2000

포유류 장생 상피세포의 하나인 파네스세포(Paneth cell)는 여러 가지 금속류를 함유하고 있으며, 생체가 과잉의 이들 금속류에 노출되거나 부족할 때에 장 내강을 통해 제거하거나 흡수함으로써 금속류의 항상성에 기여한다고 알려져 있다. 이번 연구는 이러한 연구보고에 근거하여 금속류중에서 zinc를 실험적으로 과량투여한 후 파네스세포내 zinc의 분포에 어떤 변화가 초래되는 지를 광학 및 전자현미경적 autometallography(AMG)로 관찰함으로써 파네스세포의 zinc와 관련된 세포생물학적 기능을 규명하고자 하였다. Wistar 랫드에 체중 당 20mg의 zinc chloride를 생리식염수 5ml에 녹여 복강주사한 후 2시간에 이르러 0.1 M phosphate buffer(PB)에 녹인 0.5% sodium sulphide-3% glutaraldehyde 흔합액으로 관류고정하였다. 회장(ileum)의 일부를 Dry Ice나 $CO_2$ gas로 얼린 후 cryostat을 이용하여 $20{\mu}m$ 두께의 조직절편을 만들어 및 단계의 AMG법을 시행하였다. 이와는 별도로 EM용으로 선택된 회장절편은 일련의 전자현미경 표본제작과정을 거쳐, 100nm두께의 thin section을 만들어 uranyl-lead 이중염 색 추 전자현미경으로 관찰하였다. Zinc를 투여한 동물에서 관찰된 소견은 생리식염수만을 투여한 대조군의 것과 비교할 때 큰 차이를 보였다. 우선 대조군에서는 파네스세포의 꼭대기(apex)부위에서 낱알모양을 띤 AMG양성반응 구조물(AMG grain)들이 분비과립과 사이토졸(cytosol)에서 관찰되었고, 세포사이공간에서도 적은 양의 grain이 분포하고 있었다. 반면 zinc를 투여한 랫드의 파네스세포에서는 AMG 입자가 이상의 부위에서 훨씬 많은 양의 grain이 분포해 있었으며, 특히 분비과립에서는 가장 높은 농도로 관찰되었다. 더욱이 대조군에서 관찰되지 많았던 장샘의 분비관(Lieberkuhn crypt)및 고유판 혈관의 내에서도 많은 grain이 관찰되었다. 이상의 결과를 요약하면 과량의 zinc에 노출된 생체는 혈관을 경유하여, 파네스세포의 분비과립을 매개로 하여, 장관의 내강쪽으로 과잉의 zinc 를 피내고 있는 모습을 보인다. 따라서 연구자는 파네스세포가 생체내 zinc의 양을 조절하는데 중요한 역할이 있을 것으로 본다.