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Granulation of filamentous microorganisms in a sequencing batch reactor with saline wastewater

Zhihua Li,Ting Zhang,Na Li,Xiaochang Wang,

环境科学学报(英文版) , 2010,
Abstract: Proliferation of filamentous microorganisms frequently leads to operational failure for activate sludge systems. In this study, it was found that filamentous microorganisms could grow in compact granular structure with 5% sodium chloride in the substrate. In the early period of experiment, coccoid and rode-like bacteria predominated in the yellowish-brown granules, and later the white and the black granules were developed by filamentous microorganisms. The filamentous granules exhibited low porosity and fas...
Arsenic, Lead and Microorganisms in Hair and Nails of Some Women from Saudi Arabia  [PDF]
A. R. Hashem,K. F. Abed
Journal of Medical Sciences , 2002,
Abstract: Hair and nails samples were collected from different adults women from Riyadh region, Saudi Arabia and analyzed for arsenic (As), lead (Pb) and microbial flora. The hair and nails contain higher concentrations of Pb 4.47+0.41;10.48+0.53 followed by As 0.036+0.001; 0.087+0.005, respectively. Ten genera of microorganisms were isolated from the tested samples but hair contains higher bacteria and fungi than nails. The results provide evidence of high accumulation of lead and arsenic, which might be important in dealing with metal pollution in Saudi Arabia.
Monitoring and robust adaptive control of fed-batch cultures of microorganisms exhibiting overflow metabolism [abstract]  [PDF]
Dewasme, L.,Bogaerts, P.,Vande Wouwer, A.
Biotechnologie, Agronomie, Société et Environnement , 2010,
Abstract: Overflow metabolism characterizes cells strains that are likely to produce inhibiting by-products resulting from an excess of substrate feeding and a saturated respiratory capacity. The critical substrate level separating the two different metabolic pathways is generally not well defined. Monitoring of this kind of cultures, going from model identification to state estimation, is first discussed. Then, a review of control techniques which all aim at maximizing the cell productivity of fed-batch fermentations is presented. Two main adaptive control strategies, one using an estimation of the critical substrate level as set-point and another regulating the by-product concentration, are proposed. Finally, experimental investigations of an adaptive RST control scheme using the observer polynomial for the regulation of the ethanol concentration in Saccharomyces cerevisiae fed-batch cultures ranging from laboratory to industrial scales, are also presented.
EFFECTS OF COMBINED LEAD CONTAMINATION AND ALTERNATING MAGNETIC FIELD ON THE NUMBER OF SANDY SOIL MICROORGANISMS Изменение численности микроорганизмов серопесков под влиянием сочетанного загрязнения свинцом и переменным магнитным полем
Mazanko M. S.,Kolesnikov S. I.,Denisova T. V.,Kazeev K. S.
Polythematic Online Scientific Journal of Kuban State Agrarian University , 2012,
Abstract: In the article, we have studied the effect of lead contamination, an alternating magnetic field, their combination on such groups of soil microorganisms, as ammonifying, amylolytic, nitrogen-fixing bacteria, and micromycetes. The pollution had a significant and different effect on the number of soil microorganisms. The nature and extent of this effect varied depending on the level of impact of each factor, and they were not linear
Effect of salinity shock on specific microorganisms in conventional activated sludge
活性污泥中功能性菌群抗盐度冲击性能研究

Li Lingling,Zhou Peng,
李玲玲
,周鹏

环境工程学报 , 2010,
Abstract: The effects of salt contents on the nitrifiers, denitrifiers and phosphate accumulating microorganisms (PAO) in the conventional activated sludge were studied by batch experiments. The results indicate that the inhibition coefficient is 0.86 for nitrosomonas at the salt content of 10 g/L. Nitrobacter, which is inhibited at the salt content of 5 g/L, seems to be more sensitive to high salinity than nitrosomonas. The denitrifiers possess a better salt tolerance capability than the nitrifiers. At the salt content of 50 g/L the inhibition coefficient is 0.46. PAO is also sensitive to high salinity.When the salt content is up to 20 g/L,the inhibition coefficient is 0.52 for phosphate release under anaerobic conditions. When PAO is subjected to shock loads of 5 g/L salt content, the inhibition coefficient is 0.41 for phosphate uptake under aerobic conditions.
The performance of urea-intercalated and delaminated kaolinites-adsorption kinetics involving copper and lead
Guerra, Denis L.;Airoldi, Claudio;
Journal of the Brazilian Chemical Society , 2009, DOI: 10.1590/S0103-50532009000100005
Abstract: brazilian kaolinite clay was used to study urea intercalation (kur) and delamination (kur/dl) processes. the intercalated sample was delaminated by ultrasonic treatment in acidic solution. the basal distance changed from 0.72 to 1.08 nm with increasing surface area from 20.3 to 90.5 m2 g-1 for kur and kur/dl. suspended pristine, intercalated and delaminated clays at ph 5.0 adsorbed copper and lead cations at the solid/liquid interface. the langmuir, redlich-peterson and toth adsorption isotherm models were employed in linear and nonlinear regression processes, to give b and kl values for all kaolinites. the highest adsorption capacity of 12.8 mmol g-1 was obtained with delaminated kaolinite. the kinetic parameters analyzed by the lagergren and elovich models gave a good fit for a pseudo-second order reaction with k2 in the 5.0 to 11.0 and the 4.9 to 13.0 mmol-1 min-1 ranges for copper and lead cations, respectively.
Batch Study of Liquid-Phase Adsorption of Lead Ions Using Lalang (Imperata cylindrica) Leaf Powder  [PDF]
M.A.K. Megat Hanafiah,W.S. Wan Ngah,H. Zakaria,S.C. Ibrahim
Journal of Biological Sciences , 2007,
Abstract: A batch adsorption method was applied to study the adsorption of Pb2+ ions from aqueous solution by lalang or Imperata cylindrica (IC) leaf powder. Effect of initial lead concentration, contact time, pH of solution, temperature and adsorbent dose were also investigated. A strong dependence of adsorption capacity on pH was observed as the capacity increased with increasing pH. Adsorption equilibrium was established in about 120 min. Adsorption of lead was found to increase with increasing temperature indicating endothermic nature of adsorption. The kinetic data were analyzed using various kinetic models particularly pseudo-first-order, pseudo-second-order, Ritchie`s-second-order, Elovich and intraparticle diffusion equations. Results show that the pseudo-second order kinetic model was found to agree well with the experimental data. Equilibrium isotherm data were tested using three models-Langmuir, Freundlich and Temkin. Equilibrium data agreed well with Langmuir model. The maximum adsorption capacity of lead by IC leaf powder determined from Langmuir model was 5.89 mg g-1 at pH 4.
Lead and Cadmium Removal from Aqueous Medium Using Coir Pith as Adsorbent: Batch and Fixed bed Column Studies  [cached]
B.M.W.P.K. Amarasinghe
Journal of Tropical Forestry and Environment , 2011,
Abstract: Coir pith was used as an alternative to commonly available adsorbents for heavy metal ion removal from aqueous solutions. Batch and fixed bed column experiments were conducted to study adsorption characteristics of Cd and Pb onto coir pith. Coir pith is an effective adsorbent for Pb and Cd removal. The adsorbent dose, metal ion concentration and the solution pH affects the degree of adsorption. The maximum adsorption was observed at solution pH values above 5. The equilibrium data was satisfactorily fitted to Langmuir and Freundlich isotherms. Pb showed higher adsorption capacity compared to Cd under the experimental conditions. Kinetic studies revealed that Pb and Cd uptake was fast within first 10 to 15 min of contact time and data fits to pseudo second-order model. Breakthrough curve data fits to linear Bed Depth Service Time (BDST) model and bed capacities for Pb and Cd were 41 and 28 mg/g of coir pith respectively. Key words: adsorption, heavy metals, coir pith
Lead and Cadmium Removal from Aqueous Medium Using Coir Pith as Adsorbent: Batch and Fixed bed Column Studies  [cached]
B.M.W.P.K. Amarasinghe
Journal of Tropical Forestry and Environment , 2011,
Abstract: Coir pith was used as an alternative to commonly available adsorbents for heavy metal ion removal from aqueous solutions. Batch and fixed bed column experiments were conducted to study adsorption characteristics of Cd and Pb onto coir pith. Coir pith is an effective adsorbent for Pb and Cd removal. The adsorbent dose, metal ion concentration and the solution pH affects the degree of adsorption. The maximum adsorption was observed at solution pH values above 5. The equilibrium data was satisfactorily fitted to Langmuir and Freundlich isotherms. Pb showed higher adsorption capacity compared to Cd under the experimental conditions. Kinetic studies revealed that Pb and Cd uptake was fast within first 10 to 15 min of contact time and data fits to pseudo second-order model. Breakthrough curve data fits to linear Bed Depth Service Time (BDST) model and bed capacities for Pb and Cd were 41 and 28 mg/g of coir pith respectively.
Similarity of hydrolyzing activity of human and rat small intestinal disaccharidases  [cached]
Oku T,Tanabe K,Ogawa S,Sadamori N
Clinical and Experimental Gastroenterology , 2011,
Abstract: Tsuneyuki Oku1, Kenichi Tanabe1, Shigeharu Ogawa2, Naoki Sadamori1, Sadako Nakamura11Graduate School of Human Health Science, University of Nagasaki, Siebold, Nagayo, Japan; 2Juzenkai Hospital, Kagomachi, Nagasaki, JapanBackground: The purpose of this study was to clarify whether it is possible to extrapolate results from studies of the hydrolyzing activity of disaccharidases from rats to humans.Materials and methods: We measured disaccharidase activity in humans and rats using identical preparation and assay methods, and investigated the similarity in hydrolyzing activity. Small intestinal samples without malignancy were donated by five patients who had undergone bladder tumor surgery, and homogenates were prepared to measure disaccharidase activity. Adult rat homogenates were prepared using small intestine.Results: Maltase activity was the highest among the five disaccharidases, followed by sucrase and then palatinase in humans and rats. Trehalase activity was slightly lower than that of palatinase in humans and was similar to that of sucrase in rats. Lactase activity was the lowest in humans, but was similar to that of palatinase in rats. Thus, the hydrolyzing activity of five disaccharidases was generally similar in humans and rats. The relative activity of sucrose and palatinase versus maltase was generally similar between humans and rats. The ratio of rat to human hydrolyzing activity of maltase, sucrase, and palatinase was 1.9–3.1, but this was not a significant difference. Leaf extract from Morus alba strongly inhibited the activity of maltase, sucrase, and palatinase, but not trehalase and lactase, and the degree of inhibition was similar in humans and rats. L-arabinose mildly inhibited sucrase activity, but hardly inhibited the activity of maltase, palatinase, trehalase and lactase in humans and rats. The digestibility of 1-kestose, galactosylsucrose, and panose by small intestinal enzymes was very similar between humans and rats.Conclusion: These results demonstrate that the digestibility of newly developed saccharide materials evaluated by rat small intestinal enzymes can substitute for evaluation using human enzymes.Keywords: disaccharidase, maltase, sucrase, trehalase, palatinase, digestibility
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