• Title/Summary/Keyword: LAS

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Degradation of MS(Linear Alkylbenzene Sulfonate) by Plasmid (LAS(Linear Alkybenzene Sulfonate)의 Plasmid에 의한 분해)

  • 차전옥;유진삼;백형석
    • Microbiology and Biotechnology Letters
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    • v.22 no.2
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    • pp.158-163
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    • 1994
  • Microorganisms capale of utilizing linear alkylbenzene sulfonates(LAS) as sole carbon source were isolated from industrial effluent by using LAS agar plates. The isolated strains were identified as Salmonella sp(BC-2) and Escherichia sp.(BC-3) from the results of morphological, cultural and biochemical tests. The optimal condition for the growth and biodegradation of LAS was the initial pH 7.0 and LAS concentration 0.1%. The isolated BC-2 and BC-3 strains harbored plasmid and LAS-degrading activity was lost when the plasmids were cured by mitomycin C. The plasmids were transformed into E. coli and transformants have the LAS-degrading activity. Isolated strains were examined for primary biodegradation rate of LAS in the medium by methylene blueactive substance(MBAS) method. Of these isolates, BC-2 and BC-3 strains degradated LAS upto 60% and high resistant to CdCl$_{2}$ and HgCl$_{2}$. Isolated strains were sensitive to chloramphenicol, kanamycin, rifampicin, streptomycin and tetracycline but resistant to ampicillin and lincomycin.] Its minimal inhibitory concentration(MIC) for ampicillin was more than 1500 $\mu $g/ml.

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Studies on the Adsorption of Linear Alkylbenzene Sulfonate from Waste Water by Fibrous Aminated Acrylic ion-Exchanger (아민화 아크릴계 이온교환섬유의 폐수 중 Linear Alkylbenzene Sulfonate 흡착에 관한 연구)

  • 황택성;박진원;김원종
    • Polymer(Korea)
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    • v.26 no.4
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    • pp.516-522
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    • 2002
  • The ion exchange characteristic of quaternary ammonium as functional group containing aminated acrylic fibrous ion exchanger were studied for the adsorption of linear alkylbenzene sulfonate (LAS) in a continuous ion exchange process. The adsorption capacities of aminated acrylic for LAS as the adsorption temperature were increased with increasing adsorption temperature and were equilibrated at $40^{\circ}C$. The maximum adsorption capacities as column packing ratio (L/D) were obtained at L/D>2. The adsorption capacity for LAS was increased with increasing pH and the maximum adsorption capacity as pH was obtained at pH 7. The effects of temperature and pH were similar to those of flow rate and concentration of LAS tin the breakthrough curves, the breakthrough time and slope of breakthrough corves decreased with increasing flow rate and concentration of LAS in adsorption process.

Determination of Trace Amount of Linear Alkylbenzene Sulfonates in River Water (하천수 중 미량의 Linear Alkylbenzene Sulfonate의 분석)

  • Hong, Sa Uk;Yoo, Young Chan;Chung, Hee Sun;Chung, Kyu Hyuck
    • Analytical Science and Technology
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    • v.5 no.2
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    • pp.159-167
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    • 1992
  • An improved and accurate method for the determination of linear alkybenzene sulfonate(LAS) in river water is described by using gas chromatography and GC/MS. The gas chromatograph equipped with BP-5 capillary column was satisfactory for isolation of the homologues and isomers of LAS in river water. Four LAS homologues, $C_{10}$, $C_{11}$, $C_{12}$, $C_{13}$ alkyl chains were determined in Jungrang stream, Jinwi stream and down stream of Han river tributary. Especially $5-C_{11}$, $6-C_{11}$, $2-C_{12}$ and $6-C_{13}$, $7-C_{13}$ of LAS were identified by mass chromatogram. Different composition of LAS in standard and river water expressed the distribution and fate of LAS in river water. The remarkable reduced content of $C_{12}$ and $C_{13}$ in river water implied that the biodegradation of LAS more easily occured in longer alkylchain one. This method would be applicable for determination of LAS in water with high resolution and sensitivity.

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Copper thickness and thermal reliability of microvias produced by laser-assisted seeding (LAS) process in printed circuit board (PCB) manufacture

  • Leung, E. S.W.;Yung, W. K.C.
    • International Journal of Quality Innovation
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    • v.2 no.2
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    • pp.69-92
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    • 2001
  • The laser-assisted seeding (LAS) process has potential to replace conventional electroless copper plating in Printed Circuit Board (PCB) manufacturing since it combines the steps of laser drilling and plating into one single process. In the LAS process, the single extra LAS step can metallize a microvia. Thus, the process steps can be greatly reduced and the productivity enhanced, but also the high aspect ratio microvias can be metallized. The objectives of this paper are to study the LAS copper thickness within PCB microvias and the thermal reliability of the microvias produced by this process. It was found that results were satisfactory in both the reliability test and also the LAS copper thickness which both comply with IPC standard, the copper thickness produced by the LAS process is sufficient for subsequent electro-plating process. The reliability of the microvias produced by LAS process is acceptable which are free from any voids, corner cracks, and distortion in the plated copper.

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La época de la independencia de América latina y los roles de las mujeres (라틴아메리카 독립 시기와 여성의 역할)

  • LEE, Seong hun
    • Cross-Cultural Studies
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    • v.34
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    • pp.285-306
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    • 2014
  • La historia sobre la ${\acute{e}}poca$ de la independencia y la $formac{\acute{o}}n$ de las naciones latinoamericanas enfatiza sobre todo los roles de los hombres y $espor\acute{a}dicamente$ de las mujeres. Se han considerado directrices las acciones de algunos criollos de esa epoca como $Sim{\acute{o}}n$ Bolivar y San Martín. La historiografía masculina-$c{\acute{e}}ntrica$ $est{\acute{a}}$ ignorando y marginando las luchas y los sacrificios de las mujeres que participaron en la independencia y la $formac{\acute{o}}n$ de las naciones. Por tanto, es preciso realizar una crítica a los procesos que han mantenido la tendencia machista, uno de ellos es porque no se han desatendido concepciones y cosmovisiones sobre el $g{\acute{e}}nero$. En fin, esta tendencia es porque no se ha superado la herencia colonial de manera crítica. En este contexto, este artículo intenta investigar los cambios sobre los puntos de vista y la manera de ver a las mujeres y sus actividades durante la ${\acute{e}}poca$ de la independencia. Puesto que las mujeres han sido consideradas como objetos que ocupan un espacio secundario en $comparaci{\acute{o}}n$ a los roles de los criollos. Este estudio pretende configurar nuevos puntos de vista para reestructurar nuestro enfoque tradicional sobre la independencia y las formaciones de las naciones latinoamericanas para poner en evidencia los roles de las mujeres en la historia.

Effect of the mixed culture of heterofermentative lactic acid bacteria and acid-tolerant yeast on the shelf-life of sourdough (이상발효유산균과 내산성 효모와의 혼합배양이 사워도우의 저장성에 미치는 영향)

  • Lim, Eun-Seo
    • Korean Journal of Microbiology
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    • v.52 no.4
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    • pp.471-481
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    • 2016
  • The primary objective of this study was to investigate the effects of the bacteriocin-producing heterofermentative lactic acid bacteria (LAB) and acid-resistant yeast isolated from Mukeunji, a Korean ripened kimchi on shelf-life extension and quality improvement of sourdough. According to gene sequence analysis the heterofermentative LAB that showed the antimicrobial activity against bread-spoilage Bacillus strains were identified as Leuconostoc mesenteroides LAS112, Lactobacillus brevis LAS129, and L. mesenteroides subsp. dextranicum LAB137. In addition, the yeasts that were able to grow at acidic pH were identified as Pichia membranifaciens YS05, Pichia fermentans YS19, and Pichia anomala YS26. During sourdough fermentation the levels of acetic acid and bacteriocin produced by L. brevis LAS129 strain were higher than those of L. mesenteroides LAS112 and L. mesenteroides subsp. dextranicum LAS 137 strains, whereas LAS112 strain produced the highest levels of lactic acid. The maximum bacteriocin activity (640 AU/g) against Bacillus subtilis ATCC 35421 was obtained in sourdough fermented by mixed culture of L. brevis LAS129 and P. membranifaciens YS05 or P. anomala YS26. After 24 h of fermentation at $30^{\circ}C$, the viable cell counts of LAS129 ($10^9CFU/g$) in sourdough were higher than those of the YS05 or YS26 ($10^7CFU/g$). Meanwhile, the viable cells of bread-spoilage strain in sourdough fermented with these strains were significantly (P < 0.05) lower than the control group.

A Novel High Performance Architecture for H.264/AVC Deblocking Filtering

  • Lopez, Sebastian;Tobajas, Felix;Callico, Gustavo M.;Perez, Pedro A.;De Armas, Valentin;Lopez, Jose F.;Sarmiento, Roberto
    • ETRI Journal
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    • v.29 no.3
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    • pp.396-398
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    • 2007
  • This letter presents an architecture based on a new double-filter strategy to perform the adaptive in-loop filtering process specified by the H.264/AVC standard. The proposed architecture shows considerable advantages, both in terms of hardware cost and latency, when compared with the approaches found in the most recent literature.

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A Study of the Inhibiton Effect of Cd(II), Cu(II) & Zn(II) to the Biodegradation of Linear Alkylbenzene Sulfonate (Linear Alkylbenzene Sulfonate의 생분해에서 Cd(II), Cu(II) 및 Zn(II)의 저해효과에 대한 연구)

  • Sun, Yle-Shik;Jung, Il-Hyun
    • Journal of the Korean Applied Science and Technology
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    • v.9 no.2
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    • pp.165-174
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    • 1992
  • The standardized activated sludge for the biodegradation test of anion surfactants has been produced from the collected microorganisms in the soil and the wastewaters treatment plant. The activated sludge was kept under control of the pH, dissolved oxygen, microorganisms and inoculated the basal medium flasks with LAS and LAS mixed with heavy metals [Cd(II), Cu(II), Zn(II)]. Based of results, the inhibition effect(%) of heavy metals in LAS biodegradation were 1. All 1% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 0.1mg/l, respectively 2. All 1${\sim}$10% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 1mg/l, respectively 3. All 10${\sim}$40% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 10mg/l, respectively 4. All 30${\sim}$65% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 100mg/l, respectively And toxicity order of heavy metals to the microorganisms in LAS biodegradation were Cd>Cu>Zn in low concentration(0.1${\sim}$1mg/l)and Cd>Zn>Cu in high concentration(10${\sim}$100mg/l).

A Study on the Removal of LAS using TiO2 Photocatalyst (TiO2 광촉매를 이용한 LAS의 제거에 관한 연구)

  • 김효정;오윤근;류성필
    • Journal of Environmental Science International
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    • v.11 no.7
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    • pp.757-763
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    • 2002
  • The objective of this study is to delineate removal efficiency of the Linear alkylbenzene sulfonates(LAS) in solution by $TiO_2$ photocatalytic oxidation as a function of the following different experimental conditions : initial concentration of LAS, $TiO_2$ concentration, UV wavelength and pH of the solution. It was increased with decreasing initial concentration of LAS and with decreasing pH of the solution. Removal efficiency increased with increasing $TiO_2$ concentration but was almost the same at $TiO_2$ concentration of 2 g/L and 3 g/L, i.e., for initial LAS concentration of 50 mg/L. It was removal efficiency was 85% at 150 min in the case of $TiO_2$ concentration of 0.5 g/L but 100% after 150 min in the case of $TiO_2$ concentration of 1 g/L, 100% after 110 min in the case of $TiO_2$ concentration of 2 g/L and 3 g/L. UV wavelength affection on the removal efficiency of LAS decreased in the order of 254, 312 and 365 nm as increasing wavelength. But the removal efficiency of LAS was nearly the same at UV wavelength of 254 nm and 312 nm.

Grouped Approach for the Design of H.264/AVC Motion Estimation Architectures

  • Lopez, Sebastian;Callico, Gustavo M.;Tobajas, Felix;De Armas, Valentin;Lopez, Jose F.;Sarmiento, Roberto
    • ETRI Journal
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    • v.30 no.6
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    • pp.862-864
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    • 2008
  • This letter presents a novel approach for organizing computational resources into groups within H.264/AVC motion estimation architectures, leading to reductions of up to 75% in the equivalent gate count with respect to state-of-the-art designs.

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