• Title/Summary/Keyword: Acid and Alkali

Search Result 584, Processing Time 0.036 seconds

Screening of Salicylic acid Producing Rhizobacteria Isolated from Plant Roots and Rhizosphere (식물의 뿌리와 근권으로부터 Salicylic acid를 생성하는 근권세균의 검색)

  • 이민웅
    • Korean Journal Plant Pathology
    • /
    • v.14 no.6
    • /
    • pp.598-602
    • /
    • 1998
  • Twenty two rhizobacteria were isolated from the roots and rhizosphere of radish, carnation, potato and tomato. There isolates produced a fluorescent pigment in King's B medium and identified as Pseudomonas spp. These isolates colonized roots and rhizosphere of the host plants. In the study of cultural characteristics of the bacteria, the pH of the culture broth was changed from neutral (7.0) to alkali (8.8∼9.41) and the numbers of cells were increased from 106 to 108 after 40 hr of incubation in basal standard succinate medium. The salicylic acid production identified by pink color reaction were observed in 7 bacteria. Out of these 7 salicylic acid producing bacteria, only 2 strains of bacteria such as Pseudomonas fluorescens RS006, and Pseudomonas sp. EN401 were confirmed as salicylic acid producers by optical density measurement. Therefore, for screening of salicylic acid producing bacteria from the roots and rhizosphere, color reaction of the culture medium should be done in the first step, and then optical density measurement of culture extract should be made for the confirmation of salicylic acid production.

  • PDF

Elution of Plasticizer fvom PVC Sheet in Alkaline Solutions (알카리수용액중에서 PVC Sheet로부터 가소제의 추출)

  • 신선명;전석호;한오형
    • Resources Recycling
    • /
    • v.11 no.2
    • /
    • pp.14-19
    • /
    • 2002
  • PVC sheet was treated in O~10M NaOH solutions at $80~150^{\circ}C$ for O~7 hour, in order to study the leaching phenomena of plasticizer. The yield of phthalic acid produced by hydrolysis of DOP was increased greatly with increasing temperature and NaOH concentration by accelerating of alkali catalyst. The yield of phthalic acid was reached ca. 100% in 10M NaOH at $150^{\circ}C$ over 3 hours. Therefore, the plasticizer containing 30% in PVC sheet could be hydrolyzed in alkali solutions before the occurrence of dehydrochlorination. Besides, in the thermal reaction, the pores were produced in the PVCsheet by the hydrolysis of DOP.

CO2 Absorption by Alkali-modified Amino Acid Salts (알칼리금속을 함침시킨 아미노산 염 수용액의 이산화탄소 흡수특성 연구)

  • Lim, Yun-Hui;Jo, Young-Min;Park, Joon-Seok
    • Applied Chemistry for Engineering
    • /
    • v.22 no.5
    • /
    • pp.526-531
    • /
    • 2011
  • The present study attempted to impregnate alkali metals to amino acid in order to improve $CO_2$ absorption capacity. A used amino acid was glycine, of which pH increased up to about 11 with the addition of alkalies. $CO_2$ absorption capacity of amino acid salts was evaluated in a batch and a continuous process. The absorption capacity appeared in turns as; Sodium Glycinate ${\geq}$ Lithium Glycinate > Potassium Glycinate. Amino acid salts showed lower absolute capacity of $CO_2$ absorption than primary amine (Monoethanolamine) at $20^{\circ}C$. In a continuous absorption with 10% $CO_2$ flow, the increasing the reaction temperature, the increasing rate of absorption for amino and was higher that of than amino absorbent.

Omega-7 producing alkaliphilic diatom Fistulifera sp. (Bacillariophyceae) from Lake Okeechobee, Florida

  • Berthold, David Erwin;Rosa, Nina de la;Engene, Niclas;Jayachandran, Krish;Gantar, Miroslav;Laughinghouse, Haywood Dail IV;Shetty, Kateel G.
    • ALGAE
    • /
    • v.35 no.1
    • /
    • pp.91-106
    • /
    • 2020
  • Incorporating renewable fuel into practice, especially from algae, is a promising approach in reducing fossil fuel dependency. Algae are an exceptional feedstock since they produce abundant biomass and oils in short timeframes. Algae also produce high-valued lipid products suitable for human nutrition and supplement. Achieving goals of producing algae fuels and high-valued lipids at competitive prices involves further improvement of technology, especially better control over cultivation. Manipulating microalgae cultivation conditions to prevent contamination is essential in addition to promoting optimal growth and lipid yields. Contamination of algal cultures is a major impediment to algae cultivation that can however be mitigated by choosing extremophile microalgae. This work describes the isolation of alkali-tolerant / alkaliphilic microalgae native to South Florida with ideal characteristics for cultivation. For that purpose, water samples from Lake Okeechobee were inoculated into Zarrouk's medium (pH 9-12) and incubated for 35 days. Selection resulted in isolation of three strains that were screened for biomass and lipid accumulation. Two alkali-tolerant algae Chloroidium sp. 154-1 and Chlorella sp. 154-2 were poor lipid accumulators. One of the isolates, the diatom Fistulifera sp. 154-3, was identified as a lipid accumulating, alkaliphilic organism capable of producing 0.233 g L-1 d-1 dry biomass and a lipid content of 20-30% dry weight. Lipid analysis indicated the most abundant fatty acid within Fistulifera sp. was palmitoleic acid (52%), or omega-7, followed by palmitic acid (17%), and then eicosapentanoic acid (15%). 18S rRNA phylogenetic analysis formed a well-supported clade with Fistulifera species.

The Kinetics of Delignification in Oxygen·Alkali pulping (효소(酵素)·알칼리 증해(蒸解)의 탈(脱)리그닌에 관(関)한 동역학적(動力學的) 분석(分析))

  • Jo, Byoung Muk;Shin, Dong So
    • Journal of Korean Society of Forest Science
    • /
    • v.56 no.1
    • /
    • pp.26-50
    • /
    • 1982
  • In order to obtain more detailed information concerning the degradation of lignin in the oxygen alkali pulping single stage isothermal delignification of pine wood meal (Pinus koraiensis S. et Z.) was studied in the oxygen alkali system at five temperature level ($110^{\circ}C$, $120^{\circ}C$, $130^{\circ}C$, $140^{\circ}C$, $150^{\circ}C$) for 60 min.. The rate constant, activation energy, oxygen and alkali consumption during the oxygen alkali delignification were determined by the kinetic method. The 2/5 of total lignin was eliminated at the start of the reaction. The delignification rate constant was about 3 times that of caustic soda pulping. The activation energy was about 1/3 lower than in caustic soda pulping. Like oxygen consumption, alkali consumption was also rapid early at the reaction and almost ceased after about 10 min.. The degradation reaction of lignin was strongly dependent upon the pH decrease of the cooking liquor by organic acid generated in pulping. The lignin in the oxygen alkali pulping degraded into lover molecular weight and had more hydrophillic properties. The methoxyl group decreased considerably at the first of oxygen alkali delignification, while the carbonyl, carboxyl and phenolic hydroxyl group increased rapidly.

  • PDF

Counterion Specific Conformational Transition and ion Selective Transport of a Poly(L-glutamic acid)/PVA Blend Membrane (Poly(L-glutamic acid)/PVA 블렌드막의 대이온 선택적인 구조전이와 이온투과 특성)

  • 허양일
    • Polymer(Korea)
    • /
    • v.24 no.6
    • /
    • pp.802-809
    • /
    • 2000
  • Counterion-specific helix formation and ion-selective transport of alkali metal chlorides (LiCl, NaCl, KCl, CsCl) were investigated for a poly(L-glutamic acid)(PLGA)/poly (vinyl alcohol)(PVA) blend membrane immersed in aqueous ethanol. The counterion specificity for helix formation of PLG alkali metal salts in the membrane was Li>Na>K>Cs. This specificity is ascribed to a contact ion-pair formation between the PLG carboxyl anion and the bound counterion, which depends on the energy balance between the electrostatic interaction and the desolvation. In aqueous ethanol, an appreciable ion-selectivity was observed for the permeability coefficient, i.e. Li$^{+}{\cdot}$Cl$^{-}$) formation between counterion and coion, and the latter to a specific interaction of diffusing counterions with polymer charges.

  • PDF

Purification and Analysis of Pectins (펙틴의 정제 및 분석)

  • 황재관
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.22 no.4
    • /
    • pp.500-509
    • /
    • 1993
  • Pectins present in the primary cell walls and middle lamellae of plant cell walls are extracted by water, cheating agents, acid or alkali solutions. However, some neutral contaminating components are extracted in conjunction with pectins during the extraction process. Thus, the accurate characterization of physi-cochemical properties of pectins necessitates to get rid of the impurities. In this review, dialysis, alcohol precipitation, ion exchange chromatography and metal precipitation were compared as procedures to purify the pectin extracts. In addition, the chemical methods to analyze pectins are discussed in terms of three major chemical constituents, i.e., anhydrogalacturonic acid, methoxyl groups and neutral sugars.

  • PDF

Separation of Alkali and Alkaline Earth Metal Ions Using Novel DBPDA Ion Exchanger and Its Ion Exchange Properties (새로운 DBPDA 이온교환체를 사용한 알칼리 및 알칼리 토금속 이온들의 분리와 그의 이온교환 성질)

  • Kim, Dong Won;Kim, Chang Suk;Choi, Ki Young;Jeon, Young Shin
    • Analytical Science and Technology
    • /
    • v.6 no.3
    • /
    • pp.261-265
    • /
    • 1993
  • The ion exchange capacity of DBPDA ion exchanger, {(4,5):(13,14)-dibenzo-6, 9, 12-trioxa-3, 15, 21-triazabicyclo [15.3.1] heneicosa-1(21), 17, 19-triene-2, 16-dione : DBPDA ion exchanger} was 4.2meq/g. The distribution coefficients of alkali and alkaline earth metal ions in the various concentrations of hydrochloric acid were determined using DBPDA ion exchanger. Also alkali and alkaline earth metal ions were separated using DBPDA ion exchanger. From these results the effect of pH of solution and ionic radii of the metal ions on the distribution coefficients of alkali and alkaline earth metal ions were discussed.

  • PDF

Calix[6]arene Bearing Carboxylic Acid and Amide Groups in Polymeric CTA Membrane

  • Kim, Jong-Seung;Lee, Soo-Heon;Yu, Sang-Hyeok;Cho, Moon-Hwan;Kim, Dong-Won;Kwon, Seon-Gil;Lee, Eil-Hee
    • Bulletin of the Korean Chemical Society
    • /
    • v.23 no.8
    • /
    • pp.1085-1088
    • /
    • 2002
  • Calix[6]arene having both carboxylic acid (1,3,5-) and carboxamide (2,4,6-) in an alternative way was synthesized. Transport rates of alkali and alkaline-earth metal ions were tested in bulk liquid membrane and polymer inclusion membrane. Ba2+ ion was found to give the highest transport rate among tested metal ions in both BLM and PIM systems. In PIM system, high durability (longer than 30 days) of the membrane was observed.

Glass Thinning by Fluoride Based Compounds Solution with Low Hydrofluoric acid Concentration (저불산 불소계 화합물 수용액을 이용한 글라스 박판화)

  • Kim, Ho-Tae;Gang, Dong-goo;Kim, Jin-Bae
    • Applied Chemistry for Engineering
    • /
    • v.20 no.5
    • /
    • pp.557-560
    • /
    • 2009
  • In this study, a new wet etching method and the solution for thinning the glass with the thickness below $100{\mu}m$ were investigated. For the preparation of etching solution with low hydrofluoric acid, it was effective to use $NH_4F$ or $NH_4HF_2$ as a main ingredient with the addition of sulfuric acid or nitric acid. Influence of the composition of mixed acid solution and the temperature on the etching rate was investigated. The addition of anionic surfactant provides the function to prevent the adhesion of sludge generated by the etching reaction. A new wet etching pilot device equipped with streaming generation parts was used to test etching of commercial non-alkali glass and soda lime glass. The non-alkali glass with the thickness of 640 ${\mu}m$ and soda lime glass with the thickness of $500{\mu}m$ were etched to $45{\mu}m$ and $100{\mu}m$, respectively, by using the pilot device. After the etching by pilot device, the roughness degree of the glass surface was maintained at $0.01{\sim}0.02{\mu}m$.