• 제목/요약/키워드: mixed potential

검색결과 992건 처리시간 0.031초

Single-particle Characterization of Aerosol Particles Collected Nearby a Lead Smelter in China

  • Jung, Hae-Jin;Song, Young-Chul;Liu, Xiande;Li, Yuwu;Ro, Chul-Un
    • Asian Journal of Atmospheric Environment
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    • 제6권2호
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    • pp.83-95
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    • 2012
  • China has been a top producer and exporter of refined lead products in the world since the year 2000. After the phasing-out of leaded gasoline in the late 1990s, non-ferrous metallurgy and coal combustion have been identified as potential major sources of aerosol lead in China. This paper presents the single particle analytical results of ambient aerosol particles collected near a lead smelter using a scanning electron microscopy- energy dispersive x-ray spectroscopy (SEM-EDX). Aerosol particle samples were collected over a 24-hour period, starting from 8 pm on 31 May 2002, using a high volume TSP sampler. For this near source sample, 73 particles among 377 particles analyzed (accounting for 19.4%) were lead-containing particles mixed with other species (S, Cl, K, Ca, and/or C), which probably appeared to be from a nearby lead smelter. Lead-containing particles of less than $2{\mu}m$ size in the near source sample were most frequently encountered with the relative abundances of 42%. SEM-EDX analysis of individual standard particles, such as PbO, PbS, $PbSO_4$, $PbCl_2$, and $PbCO_3$, was also performed to assist in the clear identification of lead-containing aerosol particles. Lead-containing particles were frequently associated with arsenic and zinc, indicating that the smelter had emitted those species during the non-ferrous metallurgical process. The frequently encountered particles following the lead-containing particles were mineral dust particles, such as aluminosilicates (denoted as AlSi), $SiO_2$, and $CaCO_3$. Nitrate- and sulfate-containing particles were encountered frequently in $2-4{\mu}m$ size range, and existed mostly in the forms of $Ca(NO_3,SO_4)/C$, $(Mg,Ca)SO_4/C$, and $AlSi+(NO_3,SO_4)$. Particles containing metals (e.g., Fe, Cu, and As) in this near source sample had relative abundances of approximately 10%. Although the airborne particles collected near the lead smelter contained elevated levels of lead, other types of particles, such as $CaCO_3$-containing, carbonaceous, metal-containing, nitrates, sulfates, and fly-ash particles, showed the unique signatures of samples influenced by emissions from the lead smelter.

Molecular Genetic Identification of Yeast Strains Isolated from Egyptian Soils for Solubilization of Inorganic Phosphates and Growth Promotion of Corn Plants

  • Hesham, Abd El-Latif;Mohamed, Hashem M.
    • Journal of Microbiology and Biotechnology
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    • 제21권1호
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    • pp.55-61
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    • 2011
  • Forty yeast strains isolated from soils taken from different locations in Egypt were tested for their P-solubilizing activities on the basis of analyzing the clear zone around colonies growing on a tricalcium phosphate medium after incubation for 5 days at $25^{\circ}C$, denoted as the solubilization index (SI). Nine isolates that exhibited P-solubilization potential with an SI ranging from 1.19 to 2.76 were genetically characterized as five yeasts belonging to the genus Saccharomyces cerevisiae and four non-Saccharomyces, based on a PCR analysis of the ITS1-26S region amplied by SC1/SC2 species-specific primers. The highest P-solubilization efficiency was demonstrated by isolate PSY- 4, which was identified as Saccharomyces cerevisiae by a sequence analysis of the variable D1/D2 domain of the 26S rDNA. The effects of single and mixed inoculations with yeast PSY-4 and Bacillus polymyxa on the P-uptake and growth of corn were tested in a greenhouse experiment using different levels of a phosphorus chemical fertilizer (50, 100, and 200 kg/ha super phosphate 15.5% $P_2O_5$). The results showed that inoculating the corn with yeast PSY-4 or B. polymyxa caused significant increases in the shoot and root dry weights and P-uptake in the shoots and roots. The P-fertilization level also had a significant influence on the shoot and root dry weights and P-uptake in the shoots and roots when increasing the P-level from 50 up to 200 kg/ha. Dual inoculation with yeast strain PSY-4 and B. polymyxa at a P-fertilization level of 200 kg/ha gave higher values for the shoot and root dry weights and P-uptake in the shoots and roots, yet these increases were nonsignificant when compared with dual inoculation with yeast strain PSY-4 and B. polymyxa at a P-fertilization level of 100 kg/ha. The best increases were obtained from dual inoculation with yeast strain PSY-4 and B. polymyxa at a P-fertilization level of 100 kg/ha, which induced the following percentage increases in the shoot and root dry weights, and P-uptake in the shoots and roots; 16.22%, 46.92%, 10.09%, and 31.07%, respectively, when compared with the uninoculated control (fertilized with 100 kg/ha).

친열성(親熱性) 생물막공법(生物膜工法)을 이용(利用)한 폐활성(廢活性) 슬러지의 혐기성(嫌氣性) 소화(消化) (Waste Activated Sludge Digestion with Thermophilic Attached Films)

  • 한웅전
    • 대한토목학회논문집
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    • 제5권4호
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    • pp.31-44
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    • 1985
  • 팽창형 혐기성(嫌氣性) 생물막공법(生物膜工法)(AAFEB)을 고온(高溫)($55^{\circ}C$)에서 부유물질(浮遊物質)이 많은 경우에 적용시킨 것은 최근의 일이다. 폐활성(廢活性)슬러지(WAS)는 이 공법(工法)으로 약 6 시간의 짧은 체류기간으로 효과적(效果的)으로 소화(消化)될 수 있다는 사실이 밝혀지고 있다. 만약 이러한 고율(高率)의 소화법(消化法)이 개발적용(開發適用)된다면, 현(現) 소화조(消化槽)의 소요체적(所要體積)을 99% 가량 감소(減少)시킬 수 있기 때문에 슬러지 처리분야(處理分野)에 매우 흥미로운 사실(事實)이 아닐 수 없을 것이다. 본(本) 논문(論文)은 이 공법(工法)에 대한 최근(最近) 1년(年) 반(半)동안의 연구결과를 요약한 것이다. 본(本) 연구(硏究)에 있어서 연속적(連續的)으로 주입(注入)되는 3개(個)의 실험실(實驗室) 소화조(消化槽)($55^{\circ}C$)가 사용(使用)되었다. 그 중(中) 1개(個)의 소화조(消化槽)는 AAFEB 소화조(消化槽)와의 비교(比較)를 위한 완전혼합형(完全混合形) 소화조(消化槽)였다. 2개(個)의 AAFEB 소화조(消化槽) 중에 1개(個)는 가수분해조(加水分解槽)를 별도(別途)로 설치(設置)한 2단(段)의 경우와 가수분해조(加水分解槽)가 없는 1단(段)의 경우로 구분시켜 비교하였다. 실험(實驗)에 사용(使用)된 WAS는 실험실(實驗室) 활성(活性)슬러지 반응조(反應曺)와 실제의 하수처리장(下水處理場)으로부터 채취한 것이었다. 1단(段)의 AAFEB의 경우, 결과를 보면 WAS 내의 생물분해가능(生物分解可能) 유기물질(有機物質)의 60%가 15시간의 체류기간으로 분해(分解)되였으며, 2단(段)의 경우에는 같은 체류기간에서 95%의 분해효율(分解效率)을 보였다. 고온소화(高溫消化)의 실제적용가능성(實際適用可能性)과 아울러 적용시(適用時)의 문제점 등을 검토(檢討)하였다.

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유채박 가수분해물을 이용한 중밀도섬유판(MDF) 제조용 접착제의 개발 (Development of Adhesive Resins Formulated with Rapeseed Flour Hydrolyzates for Medium Density Fiberboard (MDF))

  • 양인;한규성;최인규;김용현;안세희;오세창
    • Journal of the Korean Wood Science and Technology
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    • 제40권3호
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    • pp.177-185
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    • 2012
  • 목질 판상재료 생산을 위하여 현재 주로 사용되고 있는 석유화학계 접착제를 대체하여 재생가능한 원료로부터 대체 접착제를 개발하기 위한 관심이 증대하고 있다. 본 연구에서는 바이오 디젤 부산물인 유채박을 산 및 알칼리 가수분해를 통해 접착제를 제조하고, 이 접착제를 중밀도섬유판(MDF) 제조에 적용한 후 물성과 강도 특성을 조사하여 유채박의 중밀도 섬유판 제조용 접착제에 대한 가능성을 확인하고자 하였다. 먼저 유채박 접착제 조제를 위하여 유채박을 산과 알칼리 가수분해를 통해 개량한 다음, phenol formaldehyde (PF) prepolymer 와 혼합하여 접착제를 제조하고 이를 중밀도 섬유판 제조용 접착제로 사용하였다. 제조된 중밀도 섬유판의 평균 함수율과 밀도는 모두 KS의 기준을 만족시키는 것으로 나타났으며, 흡수 두께 팽창률은 다소 높게 나타났다. 중밀도 섬유판의 휨강도는 요소수지 접착제로 제조한 중밀도 섬유판보다 낮은 것으로 나타났지만 박리강도는 일부 조건에서 요소수지 접착제로 제조한 중밀도 섬유판보다 높게 나타나 석유화학계 접착제의 대체 접착제로의 가능성을 보여주었다. 접착성능의 향상을 위해서는 최적화되는 중밀도 섬유판의 제조공정의 변수에 대한 추가 연구가 필요할 것으로 생각된다.

Effects of Protein and Carbohydrate Supplementations on Fibre Digestion and Microbial Population of Sheep

  • Jetana, T.;Abdullah, N.;Halim, R.A.;Jalaludin, S.;Ho, Y.W.
    • Asian-Australasian Journal of Animal Sciences
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    • 제11권5호
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    • pp.510-521
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    • 1998
  • The effects of two types of protein, soybean meal (SBM) and fish meal (FM); and two types of energy supplements, corn flour (CF) and paper pulp (PP), on intake of guinea grass (Panicum maximum), fibre digestion and microbial activities in four Merino rams with an average weight of $54.4{\pm}4.5kg$ were studied. Each animal was fitted with a ruminal cannula and a duodenal cannula at the proximal position. The animals were fed twice daily with chopped guinea grass (5 cm) ad libitum and one of the four dietary supplements: 170 g FM+268 g PP; 170 g FM+268 g CF; 200 g SBM+200 g PP or 200 g SBM+200 g CF. All the supplements were mixed with 100 g molasses. In sacco and in vivo digestibilities, digesta flow rates, fermentation and microbial population were studied in a $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement of dietary treatments. The effects of energy or protein sources were not significant on grass intake of sheep. The potential degradabilities of NDF and ADF were not significantly affected by any of the supplements. However, the energy and protein sources had significant efects on disappearance rate of NDF and ADF. The disappearance rate of both NDF and ADF were significantly (p < 0.05) higher in animals fed PP when compared to animals fed CF. Animals fed FM also showed significantly (p < 0.03) higher disappearance rate of ADF than those fed SBM. Animals fed PP showed better digestion in the rumen and total tract. Total flow of NDF and ADF through the duodenum was not significantly affected by the various supplements. The mean rumen pH values (5.8-6.1) were not significantly different among the four different diets. The concentration of rumen ammonia was significantly (p < 0.0001) higher in animals fed SBM (235-266.4 mg N/L) supplement than in animals fed FM (174.9-179.7 mg N/L), while total VFA concentration was not significantly affected by both energy and protein supplements. Mean values of total VFA ranged from 72.5-82.3 mM. Molar proportions of acetate, propionate and butyrate were typical of a roughage type fermentation. Molar proportion of acetate was significantly (p < 0.0001) higher in sheep fed PP when compared to sheep fed CF. Animals fed FM had higher total viable bacterial counts, while animals fed CF showed higher protozoal numbers. Proportions of cellulolytic bacteria were only slightly higher in animals fed SBM or PP.

A Cross Sectional Study of Kretek Smoking in Indonesia as a Major Risk to Public Health

  • Palipudi, Krishna;Mbulo, Lazarous;Kosen, Soewarte;Tjandra, Aditama;Kadarmanto, Kadarmanto;Qureshi, Farukh;Andes, Linda;Sinha, Dhirendra N;Asma, Samira
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권16호
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    • pp.6883-6888
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    • 2015
  • Background: Tobacco smoking is a major cause of preventable disease and death worldwide. Kreteks are clove-flavored cigarettes made from a combination of tobacco and ground-clove mixed with a sauce, smoked widely in Indonesia. Because health and social consequences of kretek smoking are potentially as great as those of traditional cigarettes, this study examines the prevalence of kretek smoking in Indonesia and associated risk factors. Materials and Methods: The study used nationally representative Indonesia Global Adult Tobacco Survey data. Multiple logistic regression analysis was employed to identify correlates of kretek smoking. Results: One-third of Indonesian adults smoked tobacco of which about 90.0% smoked kreteks. Prevalence of kretek smoking among men (60.9%) was more than 25 times the rate among women (2.3%). Overall, the highest prevalence of kretek use was in the age group 45-54 years (36.5%), followed by 34-44 (35.1%), 25-34 (34.2 %), and 55-64 years (32.8%). By wealth index, prevalence of kreteks smoking among those in the middle index was almost 50% above the rate for the wealthiest group (36.4% vs 24.8% respectively). Logistic regression results showed that being male, being older, having less education, and being less wealthy were significant predictors of kretek smoking, while urban vs rural residence was not. Conclusions: Kretek smoking is common in Indonesia and is entrenched in the sociocultural fabric of the country. However, potential consequences of kretek smoking, particularly as risks for noncommunicable diseases, underscore the importance of a comprehensive approach to tobacco control as outlined in the World Health Organization's MPOWER strategies.

The -765G>C Polymorphism in the Cyclooxygenase-2 Gene and Digestive System Cancer: a Meta-analysis

  • Zhao, Fen;Cao, Yue;Zhu, Hong;Huang, Min;Yi, Cheng;Huang, Ying
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권19호
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    • pp.8301-8310
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    • 2014
  • Background: Published data regarding associations between the -765G>C polymorphism in cyclooxygenase-2 (COX-2) gene and digestive system cancer risk have been inconclusive. The aim of this study was to comprehensively evaluate the genetic risk of the -765G>C polymorphism in the COX-2 gene for digestive system cancer. Materials and Methods: A search was performed in Pubmed, Medline (Ovid), Embase, CNKI, Weipu, Wanfang and CBM databases, covering all studies until Feb 10, 2014. Statistical analysis was performed using Revman5.2. Results: A total of 10,814 cases and 16,174 controls in 38 case-control studies were included in this meta-analysis. The results indicated that C allele carriers (GC+CC) had a 20% increased risk of digestive system cancer when compared with the homozygote GG (odds ratio (OR)=1.20, 95% confidence interval (CI), 1.00-1.44 for GC+CC vs GG). In the subgroup analysis by ethnicity, significant elevated risks were associated with C allele carriers (GC+CC) in Asians (OR = 1.46, 95% CI=1.07-2.01, and p=0.02) and Africans (OR=2.12, 95% CI=1.57-2.87, and p< 0.00001), but not among Caucasians, Americans and mixed groups. For subgroup analysis by cancer type (GC+CC vs GG), significant associations were found between the -765G>C polymorphism and higher risk for gastric cancer (OR=1.64, 95% CI=1.03-2.61, and p=0.04), but not for colorectal cancer, oral cancer, esophageal cancer, and others. Regarding study design (GC+CC vs GG), no significant associations were found in then population-based case-control (PCC), hospital-based case-control (HCC) and family-based case-control (FCC) studies. Conclusions: This meta-analysis suggested that the -765G>C polymorphism of the COX-2 gene is a potential risk factor for digestive system cancer in Asians and Africans and gastric cancer overall.

GIS에 기반한 습지목록의 제작과 활용 (Development of GIS Based Wetland Inventory and Its Use)

  • 이기철;이재원;김용석
    • 한국지리정보학회지
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    • 제13권1호
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    • pp.50-61
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    • 2010
  • 본 연구는 낙동강 하구의 습지를 대상으로 습지생태계의 공간정보 추출을 위해 지리정보시스템 및 원격탐사 기법을 이용하여 3차원 습지목록을 제작하였다. 습지와 관련된 현장 조사는2009년 3월부터 8월까지 실시하였고, Landsat TM (2002년 10월 30일), Kompsat-2 (2008년 1월 17일 & 2008년 11월 20일) 인공위성 영상 자료와 항공 LiDAR (2009년 3월 1일) 및 국토지리정보원에서 제작된 수치지형도(1:5,000)를 사용하였다. 각종 영상자료는 기하보정한 후, 감독분류 및 무감독분류를 실시하여 현지 식생조사 자료와 비교, 분석해 습지분류도를 제작하였으며, 습지의 생산력을 분석하기 위해 낙동강 하구 습지의 우점식물종인 갈대군락의 생산성에 근거한 습지생산력 지도를 작성하였다. 또한 제작된 3차원 습지지도는 철새의 가시권 분석, 침수 모델링, 저서생물의 분포 특성 파악 등으로 다양하게 활용할 수 있는 방안을 제시하여 이러한 기법들을 잘 이용하면 우리나라 전역의 습지목록 작성에 활용될 수 있을 것이다.

A Study on the Characteristics of Knitwear Fashion Design: With a focus on Missoni, Sonia Rykiel, Azzedine Alaia

  • Chun, Hei Jung;Park, Jae Min
    • International Journal of Costume and Fashion
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    • 제13권1호
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    • pp.23-34
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    • 2013
  • The purpose of this study is to better understand the development and characteristics of knitwear fashion design by examining the transformation process of the modern knits. The subjects of the study are Missoni, Sonia Rykiel, and Azzedine Alaia, designers who are world-renowned knit designers, and the expressive techniques in their designs will be evaluated. The study also intends to analyze the aesthetic value of each designer's style through their product's silhouette, colors, and knitting techniques. On the basis of the analysis, we hope to research the factors in the designing process that will allow knits, which were made for practical purposes, to be valued as a luxury fashion item, and with the results, show the potential for knits in expanding its domain in fashion to become a more luxurious, creative fashion item. The characteristic comparison of the designers is as follows: First, in the case of colors, Missoni shows its distinct identity through a balance of splashy colors as well as nature-inspired color composition and balance. And, only with color use, is also able to express perspective, form composition, and rhythm. Sonia Rykiel designs are composed of black backgrounds with strong primary colors that are contrasted with one-point or stripes to express a light, urban image. Alaia emphasizes femininity by the use of black and white colors, which show modernity, in combination with neutral skin-toned colors, such as beige and gray. So, in other words, Missoni and Sonia Rykiel mixed colors for visual interconnectivity, while Alaia expressed femininity through the use of an achromatic color. Second, in the case of knitting techniques, Missoni uses the jacquard technique to make complex patterns that show balance of colors and patterns such as zigzag, stripe, geometries, and titan check, which are geometric, abstract, and symmetric. Sonia Rykiel who uses stripes as her trademark, most often utilizes the intarsia technique, which is expressed through one-point. Alaia combines diverse techniques, such as the Skashi weaving, by using computerized knitting. Third, as for silhouettes, Missoni eliminated exaggerated details in order to emphasize the flashy colors and delicate patterns and weavings of its designs, and this resulted in simplistic and relaxed silhouettes. Sonia Rykiel took advantage of the elasticity that the knit offers to get a tight silhouette, and in turn, emphasized the female sensuality. Alaia used curvilinear cuts that emphasized the womanly curves and gained an image considered soft and feminine.

Manufacture of Functional Koumiss supplemented with Cichorium intybus L. (chicory) Extract - Preliminary Study

  • Kim, Dong-Hyeon;Jeong, Dana;Oh, Yong-Taek;Kim, Hong-Seok;Kim, Yun-Gyeong;Song, Kwang-Young;Kang, Il-Byung;Kim, Young-Ji;Park, Jin-Hyeong;Chang, Ho-Seok;Lim, Hyon-Woo;Chon, Jung-Whan;Kim, Hyunsook;Jeong, Dong-Kwan;Seo, Kun-Ho
    • Journal of Dairy Science and Biotechnology
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    • 제35권1호
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    • pp.1-7
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    • 2017
  • Made using a natural mixed starter of lactic acid bacteria and yeast, Koumiss is a slightly alcoholic fermented mare's milk beverage, and a traditional drink of the nomadic populations of Central Asia. Cichorium intybus L. (chicory) is a sedative with potential cardioactive properties, and its oligosaccharides are beneficial in maintaining healthy gastrointestinal flora. Hence, in this study, we have generated a functional Koumiss containing two different concentrations of chicory. After fermentation of the Koumiss premix, the TA increased to 0.85~0.88%, and the pH decreased to ~4.3. The addition of either concentration of chicory had no significant effect on pH and TA. However, the taste, flavor, color, texture, and overall acceptability decreased in proportion to the added amount of chicory. This study has provided the first data on Koumiss supplemented with chicory. The results could be useful in developing high-quality Koumiss with functional activity using chicory, and allowing large-scale industrial production. Further studies are needed to determine if chicory root extract is beneficial for lifestyle-related diseases.