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Sample records for batch culture

  1. Batch variation between branchial cell cultures: An analysis of variance

    DEFF Research Database (Denmark)

    Hansen, Heinz Johs. Max; Grosell, M.; Kristensen, L.

    2003-01-01

    We present in detail how a statistical analysis of variance (ANOVA) is used to sort out the effect of an unexpected batch-to-batch variation between cell cultures. Two separate cultures of rainbow trout branchial cells were grown on permeable filtersupports ("inserts"). They were supposed...... and introducing the observed difference between batches as one of the factors in an expanded three-dimensional ANOVA, we were able to overcome an otherwisecrucial lack of sufficiently reproducible duplicate values. We could thereby show that the effect of changing the apical medium was much more marked when...... the radioactive lipid precursors were added on the apical, rather than on the basolateral, side. Theinsert cell cultures were obviously polarized. We argue that it is not reasonable to reject troublesome experimental results, when we do not know a priori that something went wrong. The ANOVA is a very useful...

  2. MASS PRODUCTION OF THE BENEFICIAL NEMATODE STEINERNEMA CARPOCAPSAE UTILIZING A FED-BATCH CULTURING PROCESS

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    Leonard D. Holmes

    2013-04-01

    Full Text Available The present study deals with the batch and fed-batch mass production of Steinernema carpocapsae. S. carpocapsae is an entomoparasitic nematode that is used as a biological control agent of soil-borne crop insect pests. The ability and efficiency of fed-batch culture process was successful through the utilization of the nematode’s bacterial symbiont Xenorhabdus nematophila. Results from the fed-batch process were compared to those obtain from the standard batch process. The fed-batch process successively improved the mass production process of S. carpocapsae employing liquid medium technology. Within the first week of the fed-batch process (day six, the nematode density obtained was 202,000 nematodes mL−1; whereas on day six, batch culture mode resulted in a nematode density of 23,000 nematodes mL−1. The fed-batch process was superior to that of batch production with a yield approximately 8.8-fold higher. In fed-batch process, the nematode yield was improved 88.6 % higher within a short amount of time compared to the batch process. Fed-batch seems to make the process more efficient and possibly economically viable.

  3. Efficient flotation of yeast cells grown in batch culture.

    Science.gov (United States)

    Palmieri, M C; Greenhalf, W; Laluce, C

    1996-05-01

    A fast flotation assay was used to select new floating yeast strains. The flotation ability did not seem to be directly correlated to total extracellular protein concentration of the culture. However, the hydrophobicity of the cell was definitely correlated to the flotation capacity. The Saccharomyces strains (FLT strains) were highly hydrophobic and showed an excellent flotation performance in batch cultures without additives (flotation agents) and with no need for a special flotation chamber or flotation column. A stable and well-organized structure was evident in the dried foam as shown by scanning electron microscopy which revealed its unique structure showing mummified cells (dehydrated) attached to each other. The attachment among the cells and the high protein concentration of the foams indicated that proteins might be involved in the foam formation. The floating strains (strains FLT) which were not flocculent and showed no tendency to aggregate, were capable of growing and producing ethanol in a synthetic medium containing high glucose concentration as a carbon source. The phenomenon responsible for flotation seems to be quite different from the flocculation phenomenon. PMID:18626952

  4. Lipid production in batch and fed-batch cultures of Rhodosporidium toruloides from 5 and 6 carbon carbohydrates

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    Wiebe Marilyn G

    2012-05-01

    Full Text Available Abstract Background Microbial lipids are a potential source of bio- or renewable diesel and the red yeast Rhodosporidium toruloides is interesting not only because it can accumulate over 50% of its dry biomass as lipid, but also because it utilises both five and six carbon carbohydrates, which are present in plant biomass hydrolysates. Methods R. toruloides was grown in batch and fed-batch cultures in 0.5 L bioreactors at pH 4 in chemically defined, nitrogen restricted (C/N 40 to 100 media containing glucose, xylose, arabinose, or all three carbohydrates as carbon source. Lipid was extracted from the biomass using chloroform-methanol, measured gravimetrically and analysed by GC. Results Lipid production was most efficient with glucose (up to 25 g lipid L−1, 48 to 75% lipid in the biomass, at up to 0.21 g lipid L−1 h−1 as the sole carbon source, but high lipid concentrations were also produced from xylose (36 to 45% lipid in biomass. Lipid production was low (15–19% lipid in biomass with arabinose as sole carbon source and was lower than expected (30% lipid in biomass when glucose, xylose and arabinose were provided simultaneously. The presence of arabinose and/or xylose in the medium increased the proportion of palmitic and linoleic acid and reduced the proportion of oleic acid in the fatty acids, compared to glucose-grown cells. High cell densities were obtained in both batch (37 g L−1, with 49% lipid in the biomass and fed-batch (35 to 47 g L−1, with 50 to 75% lipid in the biomass cultures. The highest proportion of lipid in the biomass was observed in cultures given nitrogen during the batch phase but none with the feed. However, carbohydrate consumption was incomplete when the feed did not contain nitrogen and the highest total lipid and best substrate consumption were observed in cultures which received a constant low nitrogen supply. Conclusions Lipid production in R. toruloides was lower from arabinose and mixed

  5. A Single Dynamic Metabolic Model Can Describe mAb Producing CHO Cell Batch and Fed-Batch Cultures on Different Culture Media.

    Science.gov (United States)

    Robitaille, Julien; Chen, Jingkui; Jolicoeur, Mario

    2015-01-01

    CHO cell culture high productivity relies on optimized culture medium management under fed-batch or perfused chemostat strategies enabling high cell densities. In this work, a dynamic metabolic model for CHO cells was further developed, calibrated and challenged using datasets obtained under four different culture conditions, including two batch and two fed-batch cultures comparing two different culture media. The recombinant CHO-DXB11 cell line producing the EG2-hFc monoclonal antibody was studied. Quantification of extracellular substrates and metabolites concentration, viable cell density, monoclonal antibody concentration and intracellular concentration of metabolite intermediates of glycolysis, pentose-phosphate and TCA cycle, as well as of energetic nucleotides, were obtained for model calibration. Results suggest that a single model structure with a single set of kinetic parameter values is efficient at simulating viable cell behavior in all cases under study, estimating the time course of measured and non-measured intracellular and extracellular metabolites. Model simulations also allowed performing dynamic metabolic flux analysis, showing that the culture media and the fed-batch strategies tested had little impact on flux distribution. This work thus paves the way to an in silico platform allowing to assess the performance of different culture media and fed-batch strategies.

  6. Xylitol production by Candida parapsilosis under fed-batch culture

    OpenAIRE

    Furlan Sandra A.; Castro Heizir F. de

    2001-01-01

    Xylitol production by Candida parapsilosis was investigated under fed-batch cultivation, using single (xylose) or mixed (xylose and glucose) sugars as substrates. The presence of glucose in the medium induced the production of ethanol as secondary metabolite and improved specific rates of growth, xylitol formation and substrate consumption. Fractionated supply of the feed medium at constant sugar concentration did not promote any increase on the productivity compared to the single batch culti...

  7. Xylitol production by Candida parapsilosis under fed-batch culture

    Directory of Open Access Journals (Sweden)

    Sandra A. Furlan

    2001-06-01

    Full Text Available Xylitol production by Candida parapsilosis was investigated under fed-batch cultivation, using single (xylose or mixed (xylose and glucose sugars as substrates. The presence of glucose in the medium induced the production of ethanol as secondary metabolite and improved specific rates of growth, xylitol formation and substrate consumption. Fractionated supply of the feed medium at constant sugar concentration did not promote any increase on the productivity compared to the single batch cultivation.A produção de xylitol por Candida parapsilosis foi investigada em regime de batelada alimentada, usando substratos açucarados de composição simples (xilose ou composta (xilose e glicose. A presença de glicose no meio induziu a formação de etanol como metabólito secundário. A suplementação fracionada do meio de alimentação numa concentração fixa de açúcar não resultou em aumento da produtividade em relação àquela alcançada em batelada simples.

  8. Decolouration of industrial metal-complex dyes in successive batches by active cultures of Trametes pubescens

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    Susana Rodríguez-Couto

    2014-12-01

    Full Text Available The decolouration of the metal-complex dyes Bemaplex Navy M-T (150 mg/L and Bezaktiv Blue BA (150 mg/L in nine successive batches by immobilised cultures of the white-rot fungus Trametes pubescens was studied. Two different types of immobilisation supports were used: the commercial carriers Kaldnes™ K1 (synthetic supports and sunflower-seed shells (SS (natural supports. Bemaplex showed more resistance to degradation by T. pubescens cultures than Bezaktiv, especially in the K1 cultures. Thus, SS cultures led to decolouration percentages higher than 59% for Bemaplex in all the batches save for the last two and higher than 50% for Bezaktiv in all the batches except for the 2nd and 9th ones. K1 cultures showed decolouration percentages for Bemaplex higher than 42% in batches 1, 3, 4, 5 and 7 and for Bezaktiv higher than 70% in all the batches save for the last one. Dye decolouration was mainly due to enzyme action (biodegradation.

  9. Effects of plants and essential oils on ruminal in vitro batch culture methane production and fermentation

    Science.gov (United States)

    In this study, plants (14) and essential oils (EO; 88) from plants that are naturalized to, or can be successfully grown in North America were evaluated in a batch culture in vitro screening experiments with ruminal fluid as potential anti-methanogenic additives for ruminant diets. Essential oils we...

  10. Oxygen availability strongly affects chronological lifespan and thermotolerance in batch cultures of Saccharomyces cerevisiae

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    Markus M.M. Bisschops

    2015-10-01

    Full Text Available Stationary-phase (SP batch cultures of Saccharomyces cerevisiae, in which growth has been arrested by carbon-source depletion, are widely applied to study chronological lifespan, quiescence and SP-associated robustness. Based on this type of experiments, typically performed under aerobic conditions, several roles of oxygen in aging have been proposed. However, SP in anaerobic yeast cultures has not been investigated in detail. Here, we use the unique capability of S. cerevisiae to grow in the complete absence of oxygen to directly compare SP in aerobic and anaerobic bioreactor cultures. This comparison revealed strong positive effects of oxygen availability on adenylate energy charge, longevity and thermotolerance during SP. A low thermotolerance of anaerobic batch cultures was already evident during the exponential growth phase and, in contrast to the situation in aerobic cultures, was not substantially increased during transition into SP. A combination of physiological and transcriptome analysis showed that the slow post-diauxic growth phase on ethanol, which precedes SP in aerobic, but not in anaerobic cultures, endowed cells with the time and resources needed for inducing longevity and thermotolerance. When combined with literature data on acquisition of longevity and thermotolerance in retentostat cultures, the present study indicates that the fast transition from glucose excess to SP in anaerobic cultures precludes acquisition of longevity and thermotolerance. Moreover, this study demonstrates the importance of a preceding, calorie-restricted conditioning phase in the acquisition of longevity and stress tolerance in SP yeast cultures, irrespective of oxygen availability.

  11. Screening of static culture and comparison of batch and continuous culture for the textile dye biological decolorization by Phanerochaete chrysosporium

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    J. Urra

    2006-09-01

    Full Text Available The production of manganese dependent peroxidase (MnP by Phanerochaete chrysosporium and the level of decolorization of 13 dyes were evaluated using static and agitated batch cultures and continuous cultures. A screening carried out under static conditions showed that the oxidative system has a certain affinity for azoic structures. For concentrations of 100 mg l-1 of Acid Black 1, Reactive Black 5, Reactive Orange 16 and Acid Red 27, decolorization percentages higher than 90% were obtained. In batch cultures with Acid Black 1 and Reactive Black 5 a significant increment in primary post-metabolism biomass was observed. For these last two dyes, it was possible to explore the response of the continuous system during 32 to 47 days, with concentrations between 25 to 400 mg l-1, obtaining decolorization percentages greater than 70% for 400 mg l-1.

  12. Monitoring and robust adaptive control of fed-batch cultures of microorganisms exhibiting overflow metabolism [abstract

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    Vande Wouwer, A.

    2010-01-01

    Full Text Available 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.

  13. Modelling of Escherichia coli Cultivations: Acetate Inhibition in a Fed-batch Culture

    OpenAIRE

    Stoyan Tzonkov; Olympia Roeva

    2006-01-01

    A set of three competing, unstructured models has been proposed to model biomass growth, glucose utilization, acetate formation, dissolved oxygen consumption and carbon dioxide accumulation of a fed-batch cultivation process of Escherichia coli. The inhibiting effect of acetate on growth of E. coli cultures is included in the considered models. The model identification is carried out using experimental data from the cultivation process. Genetic algorithms are used for parameter estimation. Th...

  14. Improving the batch-to-batch reproducibility of microbial cultures during recombinant protein production by regulation of the total carbon dioxide production.

    Science.gov (United States)

    Jenzsch, Marco; Gnoth, Stefan; Kleinschmidt, Martin; Simutis, Rimvydas; Lübbert, Andreas

    2007-03-10

    Batch-to-batch reproducibility of fermentation processes performed during the manufacturing processes of biologics can be increased by operating the cultures at feed rate profiles that are robust against typically arising disturbances. Remaining randomly appearing deviations from the desired path should be suppressed automatically by manipulating the feed rate. With respect to the cells' physiology it is best guiding the cultivations along an optimal profile of the specific biomass growth rate mu(t). However, there are two problems that speak for further investigations: Upon severe disturbances that may happen during the fermentation, the biomass concentration X may significantly deviate from its desired value, then a fixed mu-profile leads to a diminished batch-to-batch reproducibility. Second, the specific growth rate cannot easily be estimated online to a favourably high accuracy, hence it is difficult to determine the deviations in mu from the desired profile. The alternative discussed here solves both problems by keeping the process at the corresponding total cumulative carbon dioxide production-profile: it is robust against distortions in X and the controlled variable can accurately be measured online during cultivations of all relevant sizes. As compared to the fermentation practice currently used in industry, the experimental results, presented at the example of a recombinant protein production with Escherichia coli cells, show that CPR-based corrections lead to a considerably improved batch-to-batch reproducibility.

  15. Effect of Selenate on Viability and Selenomethionine Accumulation of Chlorella sorokiniana Grown in Batch Culture

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    Živan Gojkovic

    2014-01-01

    Full Text Available The aim of this work was to study the effect of Se(+VI on viability, cell morphology, and selenomethionine accumulation of the green alga Chlorella sorokiniana grown in batch cultures. Culture exposed to sublethal Se concentrations of 40 mg·L−1 (212 μM decreased growth rates for about 25% compared to control. A selenate EC50 value of 45 mg·L−1 (238.2 μM was determined. Results showed that chlorophyll and carotenoids contents were not affected by Se exposure, while oxygen evolution decreased by half. Ultrastructural studies revealed granular stroma, fingerprint-like appearance of thylakoids which did not compromise cell activity. Unlike control cultures, SDS PAGE electrophoresis of crude extracts from selenate-exposed cell cultures revealed appearance of a protein band identified as 53 kDa Rubisco large subunit of Chlorella sorokiniana, suggesting that selenate affects expression of the corresponding chloroplast gene as this subunit is encoded in the chloroplast DNA. Results revealed that the microalga was able to accumulate up to 140 mg·kg−1 of SeMet in 120 h of cultivation. This paper shows that Chlorella sorokiniana biomass can be enriched in the high value aminoacid SeMet in batch cultures, while keeping photochemical viability and carbon dioxide fixation activity intact, if exposed to suitable sublethal concentrations of Se.

  16. Enrichment of denitrifying methane-oxidizing microorganisms using up-flow continuous reactors and batch cultures.

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    Masashi Hatamoto

    Full Text Available Denitrifying anaerobic methane oxidizing (DAMO microorganisms were enriched from paddy field soils using continuous-flow and batch cultures fed with nitrate or nitrite as a sole electron acceptor. After several months of cultivation, the continuous-flow cultures using nitrite showed remarkable simultaneous methane oxidation and nitrite reduction and DAMO bacteria belonging to phylum NC10 were enriched. A maximum volumetric nitrite consumption rate of 70.4±3.4 mg-N·L(-1·day(-1 was achieved with very short hydraulic retention time of 2.1 hour. In the culture, about 68% of total microbial cells were bacteria and no archaeal cells were detected by fluorescence in situ hybridization. In the nitrate-fed continuous-flow cultures, 58% of total microbial cells were bacteria while archaeal cells accounted for 7% of total cell numbers. Phylogenetic analysis of pmoA gene sequence showed that enriched DAMO bacteria in the continuous-flow cultivation had over 98% sequence similarity to DAMO bacteria in the inoculum. In contrast, for batch culture, the enriched pmoA gene sequences had 89-91% sequence similarity to DAMO bacteria in the inoculum. These results indicate that electron acceptor and cultivation method strongly affect the microbial community structures of DAMO consortia.

  17. Analysis of kinetic, stoichiometry and regulation of glucose and glutamine metabolism in hybridoma batch cultures using logistic equations

    OpenAIRE

    Acosta, María Lourdes; Sánchez, Asterio; García, Francisco; Contreras, Antonio; Molina, Emilio

    2007-01-01

    Batch cultures were carried out to study the kinetic, stoichiometry, and regulation of glucose and glutamine metabolism of a murine hybridoma line. Asymmetric logistic equations (ALEs) were used to fit total and viable cell density, and nutrient and metabolite/product concentrations. Since these equations were analytically differentiable, specific rates and yield coefficients were readily calculated. Asymmetric logistic equations described satisfactorily uncontrolled batch cultures, including...

  18. Biodesulfurization of Malaysian coals using mixed microbial cultures in batch and continuous processes

    Energy Technology Data Exchange (ETDEWEB)

    Najafpour, G.D.; Azizan, A.; Harun, A. [Universiti Sains Malaysia, Darul Ridzuan (Malaysia). School of Chemical Engineering

    2001-07-01

    The determination of chemolithotrophic microorganisms capable to grown on coal with high sulfur content, made it possible to develop mixed culture processes for coal desulfurization. The ability of the microbial cultures to metabolize different sulfur compounds originated from coal in the range of 3-5% sulfur, were demonstrated in batch experimental stage. Biodesulfurization of coal as suspended solid coal particles were carried out in a broth media for coal content of 1-5% solid. Four species of microbial culture were grown on coal and acclimated for optimal growth. The coal samples obtained from Malaysian coal mine with 2-5% of sulfur content were used in batch and continuous cultures experiments. The microbial cultures were used to reduce pyrite sulfur, inorganic sulfur content of coal. The culture isolated from pharmaceutical wastewater shown that more than 80% of sulfur content of coal was reduced. The growth of microorganisms on coal shown that maximum solid content of 5% was tolerable maximum grow on 3% coal shown high cell density. Nutrient media with acidic PH value of 3-4 was required for growth of Thiobacillus thiooxidans and Thiobacillus fierrooxidans. The growth was limited at PH = 2 but at PH 3-4 growth was stimulated. Phosphate buffer was used with coal solution to monitor the PH. The PH was initially adjusted but was not controlled during the period of incubation. An optimum PH for Thiobacillus species with maximum desulfuriation was 2.65. High coal content about 10% was shown that bacterial was unable to grow. The cell dry weight, cell optical density and sulfur content of coal samples using TGA and elemental analyzer were conducted for all experiments. 10 refs., 11 figs.

  19. Growth and toxin production of Azadinium spinosum in batch and continuous culture

    OpenAIRE

    Jauffrais, Thierry; Sechet, Veronique; Herrenknecht, Christine; Tillmann, Urban; Krock, Bernd; Amzil, Zouher; Hess, Philipp

    2010-01-01

    Azaspiracids are lipophilic marine biotoxins causing gastrointestinal symptoms similar to DSP toxins. Since 1995, azaspiracids have been encountered in Europe, Africa and more recently in North and South America and Japan. The biological primary producer remained undiscovered during many years and has now been identified as Azadinium spinosum. The organism was grown using K modified medium, at 18°C with a PFD of 200 μmol.m-2.s-1 and a photoperiod of 16L/8D. Batch cultures were carried out usi...

  20. Concentrated fed-batch cell culture increases manufacturing capacity without additional volumetric capacity.

    Science.gov (United States)

    Yang, William C; Minkler, Daniel F; Kshirsagar, Rashmi; Ryll, Thomas; Huang, Yao-Ming

    2016-01-10

    Biomanufacturing factories of the future are transitioning from large, single-product facilities toward smaller, multi-product, flexible facilities. Flexible capacity allows companies to adapt to ever-changing pipeline and market demands. Concentrated fed-batch (CFB) cell culture enables flexible manufacturing capacity with limited volumetric capacity; it intensifies cell culture titers such that the output of a smaller facility can rival that of a larger facility. We tested this hypothesis at bench scale by developing a feeding strategy for CFB and applying it to two cell lines. CFB improved cell line A output by 105% and cell line B output by 70% compared to traditional fed-batch (TFB) processes. CFB did not greatly change cell line A product quality, but it improved cell line B charge heterogeneity, suggesting that CFB has both process and product quality benefits. We projected CFB output gains in the context of a 2000-L small-scale facility, but the output was lower than that of a 15,000-L large-scale TFB facility. CFB's high cell mass also complicated operations, eroded volumetric productivity, and showed our current processes require significant improvements in specific productivity in order to realize their full potential and savings in manufacturing. Thus, improving specific productivity can resolve CFB's cost, scale-up, and operability challenges.

  1. Concentrated fed-batch cell culture increases manufacturing capacity without additional volumetric capacity.

    Science.gov (United States)

    Yang, William C; Minkler, Daniel F; Kshirsagar, Rashmi; Ryll, Thomas; Huang, Yao-Ming

    2016-01-10

    Biomanufacturing factories of the future are transitioning from large, single-product facilities toward smaller, multi-product, flexible facilities. Flexible capacity allows companies to adapt to ever-changing pipeline and market demands. Concentrated fed-batch (CFB) cell culture enables flexible manufacturing capacity with limited volumetric capacity; it intensifies cell culture titers such that the output of a smaller facility can rival that of a larger facility. We tested this hypothesis at bench scale by developing a feeding strategy for CFB and applying it to two cell lines. CFB improved cell line A output by 105% and cell line B output by 70% compared to traditional fed-batch (TFB) processes. CFB did not greatly change cell line A product quality, but it improved cell line B charge heterogeneity, suggesting that CFB has both process and product quality benefits. We projected CFB output gains in the context of a 2000-L small-scale facility, but the output was lower than that of a 15,000-L large-scale TFB facility. CFB's high cell mass also complicated operations, eroded volumetric productivity, and showed our current processes require significant improvements in specific productivity in order to realize their full potential and savings in manufacturing. Thus, improving specific productivity can resolve CFB's cost, scale-up, and operability challenges. PMID:26521697

  2. Developing strategies to increase plasmid DNA production in Escherichia coli DH5α using batch culture.

    Science.gov (United States)

    Islas-Lugo, Fabiola; Vega-Estrada, Jesús; Alvis, Christian Ariel; Ortega-López, Jaime; Del Carmen Montes-Horcasitas, María

    2016-09-10

    Plasmid DNA (pDNA) production has recently increased as a result of advances in DNA vaccines. The practical development of pDNA vaccines requires high yield and productivity of supercoiled plasmid DNA (sc-pDNA). The yield and productivity are influenced by the host strain, the plasmid, the production process, and especially by growth conditions, such as the culture type and medium. We evaluated different strategies to increase pDNA production by Escherichia coli DH5α in batch culture. The strategies were driven by the development of a four single-factor experimental design and were based on the change of culture media composition in terms of carbon and nitrogen and the modification of the pH control by using NaOH or NH4OH. The results revealed the carbon (50g/L of glycerol) and nitrogen (8.34g/L of YESP) concentration in the culture medium and starting pH control with NH4OH when most of the organic nitrogen was consumed. Under these conditions, we obtained a volumetric yield of 213mg pDNA/L, a specific yield of 10mg pDNA/g DCW (dry cell weight), 92% of sc-pDNA and a productivity of 17.6mg pDNA/(Lh). The pDNA productivities reached were 42% higher than the productivities reported by other authors applying similar conditions. PMID:27374404

  3. Investigating Nitrosomonas europaea stress biomarkers in batch, continuous culture, and biofilm reactors.

    Science.gov (United States)

    Radniecki, Tyler S; Lauchnor, Ellen G

    2011-01-01

    The understanding of nitrification inhibition in ammonia oxidizing bacteria (AOB) by priority pollutants and emerging contaminants is critical in managing the nitrogen cycle to preserve current water supplies, one of the National Academy of Engineers Grand Challenges in Engineering for the twenty-first century. Nitrosomonas europaea is an excellent model AOB for nitrification inhibition experimentation due to its well-defined NH(3) metabolism and the availability of a wide range of physiological and transcriptional tools that can characterize the mechanism of nitrification inhibition and probe N. europaea's response to the inhibitor. This chapter is a compilation of the physiological and transcriptional methods that have been used to characterize nitrification inhibition of N. europaea under a wide variety of growth conditions including batch, continuously cultured, and in biofilms. The protocols presented here can be applied to other AOB, and may be readily adapted for other autotrophic bacteria (e.g., nitrite oxidizing bacteria). PMID:21514466

  4. Modelling of Escherichia coli Cultivations: Acetate Inhibition in a Fed-batch Culture

    Directory of Open Access Journals (Sweden)

    Stoyan Tzonkov

    2006-04-01

    Full Text Available A set of three competing, unstructured models has been proposed to model biomass growth, glucose utilization, acetate formation, dissolved oxygen consumption and carbon dioxide accumulation of a fed-batch cultivation process of Escherichia coli. The inhibiting effect of acetate on growth of E. coli cultures is included in the considered models. The model identification is carried out using experimental data from the cultivation process. Genetic algorithms are used for parameter estimation. The model discrimination is based on the four criteria, namely sum of square errors, Fisher criterion, Akaike information criterion and minimum description length criterion. The most suitable model is identified that reflects the state variables curves adequately by considering acetate inhibited growth according to the Jerusalimsky approach.

  5. Effect of chito-oligosaccharides over human faecal microbiota during fermentation in batch cultures.

    Science.gov (United States)

    Mateos-Aparicio, Inmaculada; Mengíbar, Marian; Heras, Angeles

    2016-02-10

    Chitosan with high number of deacetylated units, its reacetylated derivative and COS obtained through an enzymatic treatment with chitosanase were tested in pH controlled batch cultures to investigate the ability of the human faecal microbiota to utilise them. Chitosan derivatives with high number of deacetylated units decreased the bacterial populations: Bifidobacterium spp., Eubacterium rectale/Clostridium coccoides, C. Histolyticum and Bacteroides/Prevotella. On the other hand, chitosan derivatives with high content of acetylated residues maintained the tested bacterial groups and could increase Lactobacillus/Enterococcus. Regarding short chain fatty acids (SCFA), only low Mw COS increased the production in similar levels than fructo-oligossacharides (FOS). The acetylated chitosans and their COS do not appear as potential prebiotics but did not affect negatively the faecal microbiota, while derivatives with high number of deacetylated units could induce a colonic microbiota imbalance. PMID:26686171

  6. On-line optimal control for fed-batch culture of baker's yeast production

    Energy Technology Data Exchange (ETDEWEB)

    Wu, W.T.; Chen, K.C.; Chiou, H.W.

    1985-05-01

    A method of on-line optimal control for fed-batch culture of bakers yeast production is proposed. The feed rate is taken as the control variable. The specific growth rate of the yeast is the output variable and is determined from the balance equation of oxygen. A moving model is obtained by using the data from the feed rate and the specific growth rate. Based on the moving model, an optimal feed rate for fed-batch culture is then achieved. 11 references.

  7. Synchronous protein cycling in batch cultures of the yeast Saccharomyces cerevisiae at log growth phase.

    Science.gov (United States)

    Romagnoli, Gabriele; Cundari, Enrico; Negri, Rodolfo; Crescenzi, Marco; Farina, Lorenzo; Giuliani, Alessandro; Bianchi, Michele M

    2011-12-10

    The assumption that cells are temporally organized systems, i.e. showing relevant dynamics of their state variables such as gene expression or protein and metabolite concentration, while tacitly given for granted at the molecular level, is not explicitly taken into account when interpreting biological experimental data. This conundrum stems from the (undemonstrated) assumption that a cell culture, the actual object of biological experimentation, is a population of billions of independent oscillators (cells) randomly experiencing different phases of their cycles and thus not producing relevant coordinated dynamics at the population level. Moreover the fact of considering reproductive cycle as by far the most important cyclic process in a cell resulted in lower attention given to other rhythmic processes. Here we demonstrate that growing yeast cells show a very repeatable and robust cyclic variation of the concentration of proteins with different cellular functions. We also report experimental evidence that the mechanism governing this basic oscillator and the cellular entrainment is resistant to external chemical constraints. Finally, cell growth is accompanied by cyclic dynamics of medium pH. These cycles are observed in batch cultures, different from the usual continuous cultures in which yeast metabolic cycles are known to occur, and suggest the existence of basic, spontaneous, collective and synchronous behaviors of the cell population as a whole.

  8. Lactic acid production from potato peel waste by anaerobic sequencing batch fermentation using undefined mixed culture.

    Science.gov (United States)

    Liang, Shaobo; McDonald, Armando G; Coats, Erik R

    2015-11-01

    Lactic acid (LA) is a necessary industrial feedstock for producing the bioplastic, polylactic acid (PLA), which is currently produced by pure culture fermentation of food carbohydrates. This work presents an alternative to produce LA from potato peel waste (PPW) by anaerobic fermentation in a sequencing batch reactor (SBR) inoculated with undefined mixed culture from a municipal wastewater treatment plant. A statistical design of experiments approach was employed using set of 0.8L SBRs using gelatinized PPW at a solids content range from 30 to 50 g L(-1), solids retention time of 2-4 days for yield and productivity optimization. The maximum LA production yield of 0.25 g g(-1) PPW and highest productivity of 125 mg g(-1) d(-1) were achieved. A scale-up SBR trial using neat gelatinized PPW (at 80 g L(-1) solids content) at the 3 L scale was employed and the highest LA yield of 0.14 g g(-1) PPW and a productivity of 138 mg g(-1) d(-1) were achieved with a 1 d SRT. PMID:25708409

  9. Optimization of culture conditions for biological hydrogen production by Citrobacter freundii CWBI952 in batch, sequenced-batch and semicontinuous operating mode

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, Christopher; Hiligsmann, Serge; Beckers, Laurent; Masset, Julien; Thonart, Philippe [Walloon Centre of Industrial Biology, Bd du Rectorat, 29, B.40 - P.70, B-4000 Liege (Belgium); Wilmotte, Annick [Center for Protein Engineering, Institute of Chemistry, B.6-P.14, B-4000 Liege (Belgium)

    2010-02-15

    Investigations were carried out to determine the effect of the pH, the nitrogen source, iron and the dilution rate (h{sup -1}) on fermentative hydrogen production from glucose by the newly isolated strain Citrobacter freundii CWBI952. The hydrogen production rate (HPR), hydrogen yield, biomass and soluble metabolites were monitored at 30 C in 100 mL serum bottles and in a 2.3 L bioreactor operated in batch, sequenced-batch and semicontinuous mode. The results indicate that hydrogen production activity, formate biosynthesis and glucose intake rates are very sensitive to the culture pH, and that additional formate bioconversion and production of hydrogen with lower biomass yields can be obtained at pH 5.9. In a further series of cultures casein peptone was replaced by (NH{sub 4}){sub 2}SO{sub 4}, a low cost alternative nitrogen source. The ammonia-based substitute was found to be suitable for H{sub 2} production when a concentration of 0.045 g/L FeSO{sub 4} was provided. Optimal overall performances (ca. an HPR of 33.2 mL H{sub 2}/L h and a yield of 0.83mol{sub H{sub 2}}/mol{sub glucose}) were obtained in the semicontinuous culture applying the previously optimized parameters for pH, nitrogen, and iron with a dilution rate of 0.012 h{sup -1} and degassing of biogas by N{sub 2} at a 28 mL/min flow rate. (author)

  10. The use of date waste for lactic acid production by a fed-batch culture using Lactobacillus casei subsp. rhamnosus

    Directory of Open Access Journals (Sweden)

    Aicha Nancib

    2015-09-01

    Full Text Available The production of lactic acid from date juice by Lactobacillus caseisubsp. rhamnosus in batch and fed-batch cultures has been investigated. The fed-batch culture system gave better results for lactic acid production and volumetric productivity. The aim of this work is to determine the effects of the feeding rate and the concentration of the feeding medium containing date juice glucose on the cell growth, the consumption of glucose and the lactic acid production by Lactobacillus casei subsp. rhamnosus in fed-batch cultures. For this study, two concentrations of the feeding medium (62 and 100 g/L of date juice glucose were tested at different feeding rates (18, 22, 33, 75 and 150 mL/h. The highest volumetric productivity (1.3 g/L.h and lactic acid yield (1.7 g/g were obtained at a feeding rate of 33 mL/h and a date juice glucose concentration of 62 g/L in the feeding medium. As a result, most of the date juice glucose was completely utilised (residual glucose 1 g/L, and a maximum lactic acid production level (89.2 g/L was obtained.

  11. Acid protease and formation of multiple forms of glucoamylase in batch and continuous cultures of Aspergillus niger

    DEFF Research Database (Denmark)

    Aalbæk, Thomas; Reeslev, Morten; Jensen, Bo;

    2002-01-01

    with molecular weights of approx. 91 (GAI), 73 (GAII), and 59 kDa (GAIII). Data from batch fermentations with constant pH 3.0 and 5.0 showed a uniform distribution of extracellular GA forms throughout the fermentations and independent of culture growth phases. Furthermore, steady-state data from chemostat......In order to identify factors responsible for production of multiple forms of glucoamylase (GA) by Aspergillus niger Bo-1, the fungus was cultured in both complex and defined media in pH-controlled batch fermenters and chemostats. At all culture conditions three forms of GA were produced...... cultivations at constant pH 3.0 and 5.0 showed a similar distribution of extracellular GA forms and established that the nitrogen concentration of the medium (C/N ratio) did not affect the distribution of multiple forms of GA. The extracellular acid protease activity was only moderate when the fungus...

  12. Acid protease and formation of multiple forms of glycoamylase in batch and continuous cultures of Aspergillus niger

    DEFF Research Database (Denmark)

    Aalbæk, Thomas; Reeslev, Morten; Jensen, Bo;

    2002-01-01

    with molecular weights of approx. 91 (GAI), 73 (GAII), and 59 kDa (GAIII). Data from batch fermentations with constant pH 3.0 and 5.0 showed a uniform distribution of extracellular GA forms throughout the fermentations and independent of culture growth phases. Furthermore, steady-state data from chemostat......In order to identify factors responsible for production of multiple forms of glucoamylase (GA) by Aspergillus niger Bo-1, the fungus was cultured in both complex and defined media in pH-controlled batch fermenters and chemostats. At all culture conditions three forms of GA were produced...... cultivations at constant pH 3.0 and 5.0 showed a similar distribution of extracellular GA forms and established that the nitrogen concentration of the medium (C/N ratio) did not affect the distribution of multiple forms of GA. The extracellular acid protease activity was only moderate when the fungus...

  13. Recovery of an oscillatory mode of batch yeast growth in water for a pure culture.

    Science.gov (United States)

    Vadasz, A S; Vadasz, P; Abashar, M E; Gupthar, A S

    2001-12-30

    New experiments that we conducted show an oscillatory mode of batch yeast growth in water, for a pure culture of the T206 strain of Saccharomyces cerevisiae. The oscillations are damped over time, allowing the cell concentration to stabilize at the stationary equilibrium. A new proposed model that includes the complete cell growth dynamics is introduced and showed to recover the experimental oscillatory results. In addition the proposed model recovers effects that are frequently encountered in experiments such as a "Lag Phase" as well as an inflection point in the "ln curve" of the cell concentration. The proposed model recovers also the Logistic Growth Curve as a special case. For purposes of providing some interesting contrast we present additional experimental as well as computational results for the growth of the VIN7 strain of S. cerevisiae in a 5% grape juice medium. The latter indicates even stronger oscillations during the growth process. In order to capture experimentally the oscillatory growth behavior, very frequent readings are required (every 15-30 min) and the measurement process needs to be extended to longer than usual periods (over 250 h). PMID:11789940

  14. A novel approach for estimating growth phases and parameters of bacterial population in batch culture

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Using mathematical analysis, a new method has been developed for studying the growth kinetics of bacterial populations in batch culture. First, sampling data were smoothed with the spline interpolation method. Second, the instantaneous rates were derived by numerical differential techniques and finally, the derived data were fitted with the Gaussian function to obtain growth parameters. We named this the Spline-Numerical-Gaussian or SNG method. This method yielded more accurate estimates of the growth rates of bacterial populations and new parameters. It was possible to divide the growth curve into four different but continuous phases based on changes in the instantaneous rates. The four phases are the accelerating growth phase, the constant growth phase, the decelerating growth phase and the declining phase. Total DNA content was measured by flow cytometry and varied depending on the growth phase. The SNG system provides a very powerful tool for describing the kinetics of bacterial population growth. The SNG method avoids the unrealistic assumptions generally used in the traditional growth equations.

  15. Growth characteristics of freeze-tolerant baker's yeast Saccharomyces cerevisiae AFY in aerobic batch culture.

    Science.gov (United States)

    Ji, Meng; Miao, Yelian; Chen, Jie Yu; You, Yebing; Liu, Feilong; Xu, Lin

    2016-01-01

    Saccharomyces cerevisiae AFY is a novel baker's yeast strain with strong freeze-tolerance, and can be used for frozen-dough processing. The present study armed to clarify the growth characteristics of the yeast AFY. Aerobic batch culture experiments of yeast AFY were carried out using media with various initial glucose concentrations, and the culture process was analyzed kinetically. The growth of the yeast AFY exhibited a diauxic pattern with the first growth stage consuming glucose and the second growth stage consuming ethanol. The cell yield decreased with increasing initial glucose concentration in the first growth stage, and also decreased with increasing initial ethanol concentration in the second growth stage. In the initial glucose concentration range of 5.0-40.0 g/L, the simultaneous equations of Monod equation, Luedeking-Piret equation and pseudo-Luedeking-Piret equation could be used to describe the concentrations of cell, ethanol and glucose in either of the two exponential growth phases. At the initial glucose concentrations of 5.0, 10.0 and 40.0 g/L, the first exponential growth phase had a maximal specific cell growth rate of 0.52, 0.98 and 0.99 h(-1), while the second exponential growth phase had a maximal specific cell growth rate of 0.11, 0.06 and 0.07 h(-1), respectively. It was indicated that the efficiency of the yeast production could be improved by reducing the ethanol production in the first growth stage. PMID:27186467

  16. Effect of ionophores and pH on growth of Streptococcus bovis in batch and continuous culture.

    OpenAIRE

    Chow, J. M.; Russell, J B

    1990-01-01

    Batch cultures (pH 6.7) of Streptococcus bovis JB1 were severely inhibited by 1.25 and 5 microM lasalocid and monensin, respectively, even though large amounts of glucose remained in the medium. However, continuous cultures tolerated as much as 10 and 20 microM, respectively, and used virtually all of the glucose. Although continuous cultures grew with high concentrations of ionophore, the yield of bacterial protein decreased approximately 10-fold. When pH was decreased from 6.7 to 5.7, the p...

  17. Fed-batch culture of Escherichia coli for L-valine production based on in silico flux response analysis.

    Science.gov (United States)

    Park, Jin Hwan; Kim, Tae Yong; Lee, Kwang Ho; Lee, Sang Yup

    2011-04-01

    We have previously reported the development of a 100% genetically defined engineered Escherichia coli strain capable of producing L-valine from glucose with a high yield of 0.38 g L-valine per gram glucose (0.58 mol L-valine per mol glucose) by batch culture. Here we report a systems biological strategy of employing flux response analysis in bioprocess development using L-valine production by fed-batch culture as an example. Through the systems-level analysis, the source of ATP was found to be important for efficient L-valine production. There existed a trade-off between L-valine production and biomass formation, which was optimized for the most efficient L-valine production. Furthermore, acetic acid feeding strategy was optimized based on flux response analysis. The final fed-batch cultivation strategy allowed production of 32.3 g/L L-valine, the highest concentration reported for E. coli. This approach of employing systems-level analysis of metabolic fluxes in developing fed-batch cultivation strategy would also be applicable in developing strategies for the efficient production of other bioproducts.

  18. Effects of CO2 enrichment and nutrients supply intermittency on batch cultures of Isochrysis galbana.

    Science.gov (United States)

    Picardo, Marta C; de Medeiros, José Luiz; Araújo, Ofélia de Queiroz F; Chaloub, Ricardo Moreira

    2013-09-01

    Aiming at enhanced performance to increase economic feasibility of microalgae based processes, Isochrysis galbana was grown in three modes of cultivation: batch, intermittent fed batch and semi-continuous. The batch mode was conducted under two regimes of aeration: conventional aeration and CO2 enriched aeration (5% v/v in air). Increased biomass productivity without significant impact on lipid accumulation was observed for CO2 enriched aeration relatively to cultivation aerated with air only. The intermittent fed batch cultivation policy was proven to be useful for lipid accumulation, increasing the lipid content by 19.8%. However, the semi-continuous mode resulted in higher productivity due to increased biomass concentration; the biomass productivity reached 0.51 g/(Ld). Fluorescence measurements were performed; the calculated low electron transport rate showed the need to increase the irradiance. The results showed that I. galbana can be grown in semi-continuous condition at high levels of biomass productivity.

  19. Production of beta-glucosidase using immobilised Piromyces sp. KSX1 and Orpinomyces sp. 478P1 in repeat-batch culture.

    Science.gov (United States)

    McCabe, Bernadette K; Kuek, Clem; Gordon, Geoffrey L R; Phillips, Michael W

    2003-04-01

    Two anaerobic fungi, one a monocentric strain ( Piromyces sp. KSX1) and the other a polycentric strain ( Orpinomyces sp. 478P1), were immobilised in calcium alginate beads and cultured in sequential batches where spent medium (containing 0.25% cellobiose) was repeatedly drained and replaced. beta-Glucosidase production with KSX1 was maintained for 45 days over six repeated batch cultures yielding a maximum level of 107 mIU/ml. For 478P1, beta-glucosidase production was maintained for 30 days over four repeated batches yielding a maximum level of 34 mIU/ml. Although repeat-batch cultures of KSX1 produced more beta-glucosidase than strain 478P1, the maximum specific beta-glucosidase produced from these immobilised cultures was similar. The immobilised polycentric strain proved to be operationally superior to strain KSX1, as strain 478P1 did not produce any growth in the culture liquor. PMID:12687490

  20. Amino acid and glucose metabolism in fed-batch CHO cell culture affects antibody production and glycosylation

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian;

    2015-01-01

    and feeds were studied using two IgG-producing cell lines. Our results indicate that the balance of glucose and amino acid concentration in the culture is important for cell growth, IgG titer and N-glycosylation. Accordingly, the ideal fate of glucose and amino acids in the culture could be mainly towards......Fed-batch Chinese hamster ovary (CHO) cell culture is the most commonly used process for IgG production in the biopharmaceutical industry. Amino acid and glucose consumption, cell growth, metabolism, antibody titer, and N-glycosylation patterns are always the major concerns during upstream process....... Amino acids with the highest consumption rates correlate with the most abundant amino acids present in the produced IgG, and thus require sufficient availability during culture. Case-by-case analysis is necessary for understanding the effect of media and process optimization on glycosylation. We found...

  1. Conversion of a CHO cell culture process from perfusion to fed-batch technology without altering product quality.

    Science.gov (United States)

    Meuwly, F; Weber, U; Ziegler, T; Gervais, A; Mastrangeli, R; Crisci, C; Rossi, M; Bernard, A; von Stockar, U; Kadouri, A

    2006-05-01

    During the development of a new drug product, it is a common strategy to develop a first-generation process with the aim to rapidly produce material for pre-clinical and early stage clinical trials. At a later stage of the development, a second-generation process is then introduced with the aim to supply late-stage clinical trials as well as market needs. This work was aimed at comparing the performance of two different CHO cell culture processes (perfusion and fed-batch) used for the production of a therapeutically active recombinant glycoprotein at industrial pilot-scale. The first-generation process was based on the Fibra-Cel packed-bed perfusion technology. It appeared during the development of the candidate drug that high therapeutic doses were required (>100mg per dose), and that future market demand would exceed 100 kg per year. This exceeded by far the production capacity of the first-generation process, and triggered a change of technology from a packed-bed perfusion process with limited scale-up capabilities to a fed-batch process with scale-up potential to typical bioreactor sizes of 15m(3) or more. The productivity per bioreactor unit volume (in product m(-3)year(-1)) of the fed-batch process was about 70% of the level reached with the first-generation perfusion process. However, since the packed-bed perfusion system was limited in scale (0.6m(3) maximum) compared to the volumes reached in suspension cultures (15m(3)), the fed-batch was selected as second-generation process. In fact, the overall process performance (in product year(-1)) was about 18-fold higher for the fed-batch compared to the perfusion mode. Data from perfusion and fed-batch harvests samples indicated that comparable product quality (relative abundance of monomers dimers and aggregates; N-glycan sialylation level; isoforms distribution) was obtained in both processes. To further confirm this observation, purification to homogeneity of the harvest material from both processes, followed

  2. Amino acid and glucose metabolism in fed-batch CHO cell culture affects antibody production and glycosylation.

    Science.gov (United States)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian; Wagtberg Sen, Jette; Rasmussen, Søren Kofoed; Kontoravdi, Cleo; Weilguny, Dietmar; Andersen, Mikael Rørdam

    2015-03-01

    Fed-batch Chinese hamster ovary (CHO) cell culture is the most commonly used process for IgG production in the biopharmaceutical industry. Amino acid and glucose consumption, cell growth, metabolism, antibody titer, and N-glycosylation patterns are always the major concerns during upstream process optimization, especially media optimization. Gaining knowledge on their interrelations could provide insight for obtaining higher immunoglobulin G (IgG) titer and better controlling glycosylation-related product quality. In this work, different fed-batch processes with two chemically defined proprietary media and feeds were studied using two IgG-producing cell lines. Our results indicate that the balance of glucose and amino acid concentration in the culture is important for cell growth, IgG titer and N-glycosylation. Accordingly, the ideal fate of glucose and amino acids in the culture could be mainly towards energy and recombinant product, respectively. Accumulation of by-products such as NH4(+) and lactate as a consequence of unbalanced nutrient supply to cell activities inhibits cell growth. The levels of Leu and Arg in the culture, which relate to cell growth and IgG productivity, need to be well controlled. Amino acids with the highest consumption rates correlate with the most abundant amino acids present in the produced IgG, and thus require sufficient availability during culture. Case-by-case analysis is necessary for understanding the effect of media and process optimization on glycosylation. We found that in certain cases the presence of Man5 glycan can be linked to limitation of UDP-GlcNAc biosynthesis as a result of insufficient extracellular Gln. However, under different culture conditions, high Man5 levels can also result from low α-1,3-mannosyl-glycoprotein 2-β-N-acetylglucosaminyltransferase (GnTI) and UDP-GlcNAc transporter activities, which may be attributed to high level of NH4+ in the cell culture. Furthermore, galactosylation of the mAb Fc glycans

  3. Changes of in vivo fluxes through central metabolic pathways during the production of nystatin by Streptomyces noursei in batch culture

    DEFF Research Database (Denmark)

    Jonsbu, E.; Christensen, Bjarke; Nielsen, Jens

    2001-01-01

    of the amino acids and calculated fluxes of the central metabolism showed that changes in the primary and secondary metabolisms occurred simultaneously. Changes in the profiles for the integrated fluxes showed a decreased flux through the pentose phosphate pathway and an increased flux in the tricarboxylic...... acid cycle relative to the glucose uptake rate when the culture entered a phase with reduced specific growth rate and enhanced nystatin yield. The flux through the pentose phosphate pathway seemed to be adjusted according to the NADPH requirement during the different phases of the batch fermentation....

  4. Microbial lipid production by oleaginous yeast Cryptococcus sp. in the batch cultures using corncob hydrolysate as carbon source

    International Nuclear Information System (INIS)

    To realize the feasibility of biodiesel production from high-lipid cell culture, microbial lipid production by the oleaginous yeasts was studied using glucose and sucrose as carbon source. Among the tested strains, Cryptococcus sp. SM5S05 accumulated the highest levels of intracellular lipids. The crude lipid contents of Cryptococcus sp. cultured in yeast malt agar reached 30% on a dry weight basis. The accumulation of lipids strongly depended on carbon/nitrogen ratio and nitrogen concentration. The highest content of lipids, measured at a carbon/nitrogen ratio of 60–90 and at a nitrogen concentration of 0.2%, was 60–57% lipids in the dry biomass. Batch cultures using corncob hydrolysate demonstrated that there was minimal inhibitory effect with a reducing sugar concentration of 60 g l−1 or higher. Batch cultures of Cryptococcus sp. SM5S05 in the corncob hydrolysate medium with 60 g l−1 glucose resulted in a dry biomass, lipid yields, and content of 12.6 g l−1, 7.6 g l−1, and 60.2%, respectively. The lipids contained mainly long-chain saturated and unsaturated fatty acids with 16 and 18 carbon atoms. The fatty acid profile of Cryptococcus oils was quite similar to that of conventional vegetable oil. The cost of lipid production could be further reduced with corncob hydrolysate being utilized as the raw material for the oleaginous yeast. The results showed that the microbial lipid from Cryptococcus sp. was a potential alternative resource for biodiesel production. - Highlights: • Microbial oil production from oleaginous yeast Cryptococcus sp. was studied. • Accumulation of lipid strongly depended on C/N ratio and nitrogen concentration. • Cultures in hydrolysate medium with 60 g/l glucose resulted in maximum lipid yields. • Maximal lipid content in the Cryptococcus sp. were 60.2% on dried weight basis

  5. The effect of rhizosphere on growth of Sphingomonas chlorophenolica ATCC 39723 during pentachlorophenol (PCP biodegradation in batch culture and soil

    Directory of Open Access Journals (Sweden)

    Ken Killhan

    2006-12-01

    Full Text Available Studies on the influence of the rhizosphere on the growth of Sphingomonas chlorophenolica during Pentacholophenol (PCP degradation in batch culture and in soil were carried out. In batch culture, a basal minimal medium with or without rhizosphere exudates extracted from winter wheat was used. In soil systems, degradation experiments were performed in the presence and absence of plants. Measurements of PCP concentrations were made using high performance liquid chromatography analysis (HPLC. Bacterial analyses of S. chlorophenolica were carried out by plating on MSM medium. The results showed that the rhizosphere exudates stimulated the growth of the cells of S. chlorophenolica at concentrations of 50 and 80mg kg dry wt soil –1 as well as stimulating the ability of S. chlorophenolica to degrade PCP at a concentration of 80mg Kg dry wt soil -1. In addition, pentachlorophenol had an adverse effect on the growth of S. chlorophenolica. The introduction of S.chlorophenolica into the loamy soil with plants showed a faster degradation when compared to the inoculated soil without plants. There was a significant increase of S. chlorophenolica in the roots in comparison to those in the soil. This study showed that the presence of the inoculum S. chlorophenolica enhanced the PCP degradation in a loamy soil and it indicates the potential for a treatment process under a appropriate environmental conditions such as there present in soil systems.

  6. A multi-pronged investigation into the effect of glucose starvation and culture duration on fed-batch CHO cell culture

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian;

    2015-01-01

    In this study, omics-based analysis tools were used to explore the effect of glucose starvation and culture duration on monoclonal antibody (mAb) production in fed-batch CHO cell culture to gain better insight into how these parameters can be controlled to ensure optimal mAb productivity...... and quality. Titer and N-glycosylation of mAbs, as well as proteomic signature and metabolic status of the production cells in the culture were assessed. We found that the impact of glucose starvation on the titer and N-glycosylation of mAbs was dependent on the degree of starvation during early stationary...... phase of the fed-batch culture. Higher degree of glucose starvation reduced intracellular concentrations of UDP-GlcNAc and UDP-GalNAc, but increased the levels of UDP-Glc and UDP-Gal. Increased GlcNAc and Gal occupancy correlated well with increased degree of glucose starvation, which can be attributed...

  7. In Vitro Growth of Curcuma longa L. in Response to Five Mineral Elements and Plant Density in Fed-Batch Culture Systems

    Science.gov (United States)

    El-Hawaz, Rabia F.; Bridges, William C.; Adelberg, Jeffrey W.

    2015-01-01

    Plant density was varied with P, Ca, Mg, and KNO3 in a multifactor experiment to improve Curcuma longa L. micropropagation, biomass and microrhizome development in fed-batch liquid culture. The experiment had two paired D-optimal designs, testing sucrose fed-batch and nutrient sucrose fed-batch techniques. When sucrose became depleted, volume was restored to 5% m/v sucrose in 200 ml of modified liquid MS medium by adding sucrose solutions. Similarly, nutrient sucrose fed-batch was restored to set points with double concentration of treatments’ macronutrient and MS micronutrient solutions, along with sucrose solutions. Changes in the amounts of water and sucrose supplementations were driven by the interaction of P and KNO3 concentrations. Increasing P from 1.25 to 6.25 mM increased both multiplication and biomass. The multiplication ratio was greatest in the nutrient sucrose fed-batch technique with the highest level of P, 6 buds/vessel, and the lowest level of Ca and KNO3. The highest density (18 buds/vessel) produced the highest fresh biomass at the highest concentrations of KNO3 and P with nutrient sucrose fed-batch, and moderate Ca and Mg concentrations. However, maximal rhizome dry biomass required highest P, sucrose fed-batch, and a moderate plant density. Different media formulations and fed-batch techniques were identified to maximize the propagation and storage organ responses. A single experimental design was used to optimize these dual purposes. PMID:25830292

  8. In vitro growth of Curcuma longa L. in response to five mineral elements and plant density in fed-batch culture systems.

    Science.gov (United States)

    El-Hawaz, Rabia F; Bridges, William C; Adelberg, Jeffrey W

    2015-01-01

    Plant density was varied with P, Ca, Mg, and KNO3 in a multifactor experiment to improve Curcuma longa L. micropropagation, biomass and microrhizome development in fed-batch liquid culture. The experiment had two paired D-optimal designs, testing sucrose fed-batch and nutrient sucrose fed-batch techniques. When sucrose became depleted, volume was restored to 5% m/v sucrose in 200 ml of modified liquid MS medium by adding sucrose solutions. Similarly, nutrient sucrose fed-batch was restored to set points with double concentration of treatments' macronutrient and MS micronutrient solutions, along with sucrose solutions. Changes in the amounts of water and sucrose supplementations were driven by the interaction of P and KNO3 concentrations. Increasing P from 1.25 to 6.25 mM increased both multiplication and biomass. The multiplication ratio was greatest in the nutrient sucrose fed-batch technique with the highest level of P, 6 buds/vessel, and the lowest level of Ca and KNO3. The highest density (18 buds/vessel) produced the highest fresh biomass at the highest concentrations of KNO3 and P with nutrient sucrose fed-batch, and moderate Ca and Mg concentrations. However, maximal rhizome dry biomass required highest P, sucrose fed-batch, and a moderate plant density. Different media formulations and fed-batch techniques were identified to maximize the propagation and storage organ responses. A single experimental design was used to optimize these dual purposes.

  9. Efficacy of a commercial probiotic relative to oxytetracycline as Gram-negative bacterial control agents in a rotifer (Brachionus plicatilis) batch culture

    Science.gov (United States)

    Two trials were conducted to evaluate two gram-negative bacterial control strategies in batch cultures of the rotifer Brachionus plicatilis. In the first trial, rotifers at an initial density of 47/mL were cultured for 5 d and dosed with a 10-mg/L solution of either oxytetracycline or a commercial p...

  10. Comparison of biomass estimation techniques for a Bacillus thuringiensis fed-batch culture

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, C.C.F. [University of Newcastle upon Tyne (United Kingdom). Dept. of Chemical and Process Engineering]. E-mail: C.C.F.Cunha@newcastle.ac.uk; Souza Junior, M.B. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Escola de Quimica]. E-mail: mbsj@h2o.eq.ufrj.br

    2001-03-01

    In this work, the ability of artificial neural nets was investigated for the on-line biomass prediction of the simulated growth of a strain of Bacillus thuringiensis in fed-batch mode. For this purpose, multilayered backpropagation nets with sigmoid nodes were trained. The patterns were composed of input data on current values of biomass concentration, limiting substrate concentration and dilution rate, and output data on prediction of biomass concentration for the following step. The dilution rate was disturbed by a PRBS input, and simulations were conducted using a phenomenological experimentally validated model. The nets were able to predict the biomass concentration for different feeding techniques, and they were also compared with the variable estimation technique using the extended Kalman filter. (author)

  11. Fingerprint detection and process prediction by multivariate analysis of fed-batch monoclonal antibody cell culture data.

    Science.gov (United States)

    Sokolov, Michael; Soos, Miroslav; Neunstoecklin, Benjamin; Morbidelli, Massimo; Butté, Alessandro; Leardi, Riccardo; Solacroup, Thomas; Stettler, Matthieu; Broly, Hervé

    2015-01-01

    This work presents a sequential data analysis path, which was successfully applied to identify important patterns (fingerprints) in mammalian cell culture process data regarding process variables, time evolution and process response. The data set incorporates 116 fed-batch cultivation experiments for the production of a Fc-Fusion protein. Having precharacterized the evolutions of the investigated variables and manipulated parameters with univariate analysis, principal component analysis (PCA) and partial least squares regression (PLSR) are used for further investigation. The first major objective is to capture and understand the interaction structure and dynamic behavior of the process variables and the titer (process response) using different models. The second major objective is to evaluate those models regarding their capability to characterize and predict the titer production. Moreover, the effects of data unfolding, imputation of missing data, phase separation, and variable transformation on the performance of the models are evaluated. PMID:26399784

  12. Batch fermentative hydrogen production by enriched mixed culture: Combination strategy and their microbial composition.

    Science.gov (United States)

    Sivagurunathan, Periyasamy; Sen, Biswarup; Lin, Chiu-Yue

    2014-02-01

    The effect of individual and combined mixed culture on dark fermentative hydrogen production performance was investigated. Mixed cultures from cow dung (C1), sewage sludge (C2), and pig slurry (C3) were enriched under strict anaerobic conditions at 37°C with glucose as the sole carbon source. Biochemical hydrogen production test in peptone-yeast-glucose (PYG) and basal medium was performed for individual mixed cultures (C1, C2 and C3) and their combinations (C1-C2, C2-C3, C1-C3 and C1-C2-C3) at a glucose concentration of 10 g/L, 37°C and initial pH 7. Maximum hydrogen yields (HY) of 2.0 and 1.86 [Formula: see text] by C2, and 1.98 and 1.95 mol(H2)/mol(glucose) by C2-C3 were obtained in PYG and basal medium, respectively. Butyrate and acetate were the major soluble metabolites produced by all the cultures, and the ratio of butyrate to acetate was ∼2 fold higher in basal medium than PYG medium, indicating strong influence of media formulation on glucose catabolism. The major hydrogen-producing bacterial strains, observed in all mixed cultures, belonged to Clostridium butyricum, C. saccharobutylicum, C. tertium and C. perfringens. The hydrogen production performance of the combined mixed culture (C2-C3) was further evaluated on beverage wastewater (10 g/L) at pH 7 and 37°C. The results showed an HY of 1.92 mol(H2)/mol(glucose-equivalent). Experimental evidence suggests that hydrogen fermentation by mixed culture combination could be a novel strategy to improve the HY from industrial wastewater. PMID:24095211

  13. Batch fermentative hydrogen production by enriched mixed culture: Combination strategy and their microbial composition.

    Science.gov (United States)

    Sivagurunathan, Periyasamy; Sen, Biswarup; Lin, Chiu-Yue

    2014-02-01

    The effect of individual and combined mixed culture on dark fermentative hydrogen production performance was investigated. Mixed cultures from cow dung (C1), sewage sludge (C2), and pig slurry (C3) were enriched under strict anaerobic conditions at 37°C with glucose as the sole carbon source. Biochemical hydrogen production test in peptone-yeast-glucose (PYG) and basal medium was performed for individual mixed cultures (C1, C2 and C3) and their combinations (C1-C2, C2-C3, C1-C3 and C1-C2-C3) at a glucose concentration of 10 g/L, 37°C and initial pH 7. Maximum hydrogen yields (HY) of 2.0 and 1.86 [Formula: see text] by C2, and 1.98 and 1.95 mol(H2)/mol(glucose) by C2-C3 were obtained in PYG and basal medium, respectively. Butyrate and acetate were the major soluble metabolites produced by all the cultures, and the ratio of butyrate to acetate was ∼2 fold higher in basal medium than PYG medium, indicating strong influence of media formulation on glucose catabolism. The major hydrogen-producing bacterial strains, observed in all mixed cultures, belonged to Clostridium butyricum, C. saccharobutylicum, C. tertium and C. perfringens. The hydrogen production performance of the combined mixed culture (C2-C3) was further evaluated on beverage wastewater (10 g/L) at pH 7 and 37°C. The results showed an HY of 1.92 mol(H2)/mol(glucose-equivalent). Experimental evidence suggests that hydrogen fermentation by mixed culture combination could be a novel strategy to improve the HY from industrial wastewater.

  14. Fermentative hydrogen yields from different sugars by batch cultures of metabolically engineered Escherichia coli DJT135

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Dipankar; Hallenbeck, Patrick C. [Departement de Microbiologie et Immunologie, Universite de Montreal, CP 6128 succursale Centre-ville, Montreal, Quebec H3C 3J7 (Canada)

    2009-10-15

    Future sustainable production of biofuels will depend upon the ability to use complex substrates present in biomass if the use of simple sugars derived from food crops is to be avoided. Therefore, organisms capable of using a variety of fermentable carbon sources must be found or developed for processes that could produce hydrogen via fermentation. Here we have examined the ability of a metabolically engineered strain of Escherichia coli, DJT135, to produce hydrogen from glucose as well as various other carbon sources, including pentoses. The effects of pH, temperature and carbon source were investigated in batch experiments. Maximal hydrogen production from glucose was obtained at an initial pH of 6.5 and temperature of 35 C. Kinetic growth studies showed that the {mu}max was 0.0495 h{sup -1} with a Ks of 0.0274 g L{sup -1} when glucose was the sole carbon source in M9 (1X) minimal medium. Among the many sugar and sugar derivatives tested, hydrogen yields were highest with fructose, sorbitol and D-glucose; 1.27, 1.46 and 1.51 mol H{sub 2} mol{sup -1} substrate respectively. (author)

  15. O2 evolution and cyclic electron flow around photosystem I in long-term ground batch culture of Euglena gracilis

    Science.gov (United States)

    An, Yanjun; Wang, Suqin; Hao, Zongjie; Zhou, Yiyong; Liu, Yongding

    2014-12-01

    Based on the purpose of better exploring the function of green producers in the closed aquatic biological life support system, the condition of dynamic O2 evolution and performance of cyclic electron flow around photosystem I (CEF-PSI) in long-term ground batch culture of Euglena gracilis were studied, the relationship between linear electron flow (LEF) and CEF-PSI was revealed, the function of CEF-PSI was investigated. Excellent consistency in O2 evolution pattern was observed in cultures grown in both closed and open containers, O2 evolution was strictly suppressed in phase 1, but the rate of it increased significantly in phase 2. CEF-PSI was proposed to be active during the whole course of cultivation, even in the declining phase 3, it still operated at the extent of 47-55%. It is suggested that the relationship between LEF and CEF-PSI is not only competition but also reciprocity. CEF-PSI was proposed to contribute to the considerable growth in phase 1; it was also suggested to play an important protective role against photosystem II (PSII) photoinhibition at the greatly enhanced level (approximately 80-95%) on the 2nd day. Our results in this research suggest that E. gracilis had very particular photosynthetic characteristics, the strict O2 evolution suppression in the initial culture phase might be a special light acclimation behavior, and CEF-PSI could be an important mechanism involved in this kind of adaptation to the changeable light environment.

  16. Acquisition of data from on-line laser turbidimeter and calculation of some kinetic variables in computer-coupled automated fed-batch culture

    International Nuclear Information System (INIS)

    Output signals of a commercially available on-line laser turbidimeter exhibit fluctuations due to air and/or CO2 bubbles. A simple data processing algorithm and a personal computer software have been developed to smooth the noisy turbidity data acquired, and to utilize them for the on-line calculations of some kinetic variables involved in batch and fed-batch cultures of uniformly dispersed microorganisms. With this software, about 103 instantaneous turbidity data acquired over 55 s are averaged and convert it to dry cell concentration, X, every minute. Also, volume of the culture broth, V, is estimated from the averaged output data of weight loss of feed solution reservoir, W, using an electronic balance on which the reservoir is placed. Then, the computer software is used to perform linear regression analyses over the past 30 min of the total biomass, VX, the natural logarithm of the total biomass, ln(VX), and the weight loss, W, in order to calculate volumetric growth rate, d(VX)/dt, specific growth rate, μ [ = dln(VX)/dt] and the rate of W, dW/dt, every minute in a fed-batch culture. The software used to perform the first-order regression analyses of VX, ln(VX) and W was applied to batch or fed-batch cultures of Escherichia coli on minimum synthetic or natural complex media. Sample determination coefficients of the three different variables (VX, ln(VX) and W) were close to unity, indicating that the calculations are accurate. Furthermore, growth yield, Yx/s, and specific substrate consumption rate, qsc, were approximately estimated from the data, dW/dt and in a ‘balanced’ fed-batch culture of E. coli on the minimum synthetic medium where the computer-aided substrate-feeding system automatically matches well with the cell growth. (author)

  17. Fermentation and growth response of a primary poultry isolate of Salmonella typhimurium grown under strict anaerobic conditions in continuous culture and amino acid-limited batch culture.

    Science.gov (United States)

    Maciorowski, K G; Nisbet, D J; Ha, S D; Corrier, D E; DeLoach, J R; Ricke, S C

    1997-01-01

    Salmonella typhimurium is a significant hazard to consumer health that is carried asymptomatically in poultry gastrointestinal tracts. Nurmi cultures may prevent Salmonella colonization in young chicks, but the mechanism of competitive exclusion is unclear. Modeling Salmonella's metabolism in pure culture may allow for greater definition in choosing strains for Nurmi cultures. The growth rates and affinity constants of S. typhimurium growing in amino acid-limited conditions were determined in batch culture and compared to primary poultry isolates of cecal strains. Serine and NH4Cl were the best N sources for growth of all organisms tested in this study. The fermentation response of S. typhimurium was also monitored in continuous culture at a slow dilution rate of 0.021 h-1. S. typhimurium was found to adapt to VL media, with trends in protein disappearance, Yglucose, and Yprotein. This may show that amino acid or protein concentrations may be an integral component of the initial establishment of S. typhimurium in the cecum. PMID:9192013

  18. Fermentation and growth response of a primary poultry isolate of Salmonella typhimurium grown under strict anaerobic conditions in continuous culture and amino acid-limited batch culture.

    Science.gov (United States)

    Maciorowski, K G; Nisbet, D J; Ha, S D; Corrier, D E; DeLoach, J R; Ricke, S C

    1997-01-01

    Salmonella typhimurium is a significant hazard to consumer health that is carried asymptomatically in poultry gastrointestinal tracts. Nurmi cultures may prevent Salmonella colonization in young chicks, but the mechanism of competitive exclusion is unclear. Modeling Salmonella's metabolism in pure culture may allow for greater definition in choosing strains for Nurmi cultures. The growth rates and affinity constants of S. typhimurium growing in amino acid-limited conditions were determined in batch culture and compared to primary poultry isolates of cecal strains. Serine and NH4Cl were the best N sources for growth of all organisms tested in this study. The fermentation response of S. typhimurium was also monitored in continuous culture at a slow dilution rate of 0.021 h-1. S. typhimurium was found to adapt to VL media, with trends in protein disappearance, Yglucose, and Yprotein. This may show that amino acid or protein concentrations may be an integral component of the initial establishment of S. typhimurium in the cecum.

  19. LIPID PRODUCTION BY DUNALIELLA SALINA IN BATCH CULTURE: EFFECTS OF NITROGEN LIMITATION AND LIGHT INTENSITY

    Energy Technology Data Exchange (ETDEWEB)

    Weldy, C.S.; Huesemann, M.

    2007-01-01

    Atmospheric carbon dioxide (CO2) concentrations are increasing and may cause unknown deleterious environmental effects if left unchecked. The Intergovernmental Panel on Climate Change (IPCC) has predicted in its latest report a 2°C to 4°C increase in global temperatures even with the strictest CO2 mitigation practices. Global warming can be attributed in large part to the burning of carbon-based fossil fuels, as the concentration of atmospheric CO2 is directly related to the burning of fossil fuels. Biofuels which do not add CO2 to the atmosphere are presently generated primarily from terrestrial plants, i.e., ethanol from corn grain and biodiesel from soybean oil. The production of biofuels from terrestrial plants is severely limited by the availability of fertile land. Lipid production from microalgae and its corresponding biodiesel production have been studied since the late 1970s but large scale production has remained economically infeasible due to the large costs of sterile growing conditions required for many algal species. This study focuses on the potential of the halophilic microalgae species Dunaliella salina as a source of lipids and subsequent biodiesel production. The lipid production rates under high light and low light as well as nitrogen suffi cient and nitrogen defi cient culture conditions were compared for D. salina cultured in replicate photobioreactors. The results show (a) cellular lipid content ranging from 16 to 44% (wt), (b) a maximum culture lipid concentration of 450mg lipid/L, and (c) a maximum integrated lipid production rate of 46mg lipid/L culture*day. The high amount of lipids produced suggests that D. salina, which can be mass-cultured in non-sterile outdoor ponds, has strong potential to be an economically valuable source for renewable oil and biodiesel production.

  20. ON-LINE MONITORING OF BIOMASS CONCENTRATION BASED ON A CAPACITANCE SENSOR: ASSESSING THE METHODOLOGY FOR DIFFERENT BACTERIA AND YEAST HIGH CELL DENSITY FED-BATCH CULTURES

    Directory of Open Access Journals (Sweden)

    A. C. L. Horta

    2015-12-01

    Full Text Available Abstract The performance of an in-situ capacitance sensor for on-line monitoring of biomass concentration was evaluated for some of the most important microorganisms in the biotechnology industry: Escherichia coli, Saccharomyces cerevisiae, Pichia pastoris and Bacillus megaterium. A total of 33 batch and fed-batch cultures were carried out in a bench-scale bioreactor and biomass formation trends were followed by dielectric measurements during the growth phase as well as the induction phase, for 5 recombinant E. coli strains. Permittivity measurements and viable cellular concentrations presented a linear correlation for all the studied conditions. In addition, the permittivity signal was further used for inference of the cellular growth rate. The estimated specific growth rates mirrored the main trends of the metabolic states of the different cells and they can be further used for setting-up control strategies in fed-batch cultures.

  1. Isomaltulose production using free cells: optimisation of a culture medium containing agricultural wastes and conversion in repeated-batch processes.

    Science.gov (United States)

    Kawaguti, Haroldo Y; Buzzato, Michele F; Sato, Hélia H

    2007-04-01

    The enzyme glucosyltransferase is an industrially important enzyme since it produces non-cariogenic isomaltulose (6-O-alpha-D-glucopyronosyl-1-6-D-fructofuranose) from sucrose by intramolecular transglucosylation. The experimental designs and response surface methodology (RSM) were applied for the optimisation of the nutrient concentrations in the culture medium for the production of glucosyltransferase by Erwinia sp. D12 in shaken flasks at 200 rpm and 30 degrees C. A statistical analysis of the results showed that, in the range studied, the factors had a significant effect (P sugar cane molasses (150 g l(-1)), corn steep liquor (20 g l(-1)), yeast extract Prodex Lac SD (15 g l(-1)) and K2HPO4 (0.5 g l(-1)) after 8 h at 30 degrees C. The production of cell biomass by the strain of Erwinia sp. D12 was carried out in a 6.6-l fermenter with a mixing rate of 200 rpm and an aeration rate of 1 vvm. Fermentation time, cellular growth, medium pH and glucosyltransferase production were observed. The greatest glucosyltransferase activity was 22.49 U/ml, obtained after 8 h of fermentation. The isomaltulose production from sucrose was performed using free Erwinia sp. D12 cells in a batch process using an orbital shaker. The influence of the parameters sucrose concentration, temperature, pH, and cell concentration on the conversion of sucrose into isomaltulose was studied. The free cells showed a high conversion rate of sucrose into isomaltulose using batch fermentation, obtaining an isomaltulose yield of 72.11% from sucrose solution 35% at 35 degrees C. PMID:17186209

  2. Metabolism of Aromatic Amino Acids during the Growth Cycle of Batch Suspension Cultures of Catharanthus roseus

    OpenAIRE

    Nagaoka, Noriko; ASHIHARA, Hiroshi

    1988-01-01

    Profiles of the levels and metabolism of aromatic compounds in suspension-cultured cells of Catharanthus roseus during the growth cycle were determined. The level of total protein-amino acids, i.e., sum of the amounts of amino acids in hydrolyzates of proteins, and the level of total phenolic acids increased after transfer of the cells in the stationary phase to fresh Murashige-Skoog medium. The maximum levels of the proteinamino acids and those of the phenolic acids were observed on days 3-5...

  3. Production of functional killer protein in batch cultures upon a shift from aerobic to anaerobic conditions

    Directory of Open Access Journals (Sweden)

    Gildo Almeida da Silva

    2011-06-01

    Full Text Available The aim of this work was to study the production of functional protein in yeast culture. The cells of Saccharomyces cerevisiae Embrapa 1B (K+R+ killed a strain of Saccharomyces cerevisiae Embrapa 26B (K-R-in grape must and YEPD media. The lethal effect of toxin-containing supernatant and the effect of aeration upon functional killer production and the correlation between the products of anaerobic metabolism and the functional toxin formation were evaluated. The results showed that at low sugar concentration, the toxin of the killer strain of Sacch. cerevisiae was only produced under anaerobic conditions . The system of killer protein production showed to be regulated by Pasteur and Crabtree effects. As soon as the ethanol was formed, the functional killer toxin was produced. The synthesis of the active killer toxin seemed to be somewhat associated with the switch to fermentation process and with concomitant alcohol dehydrogenase (ADH activity.

  4. Does the 14C method estimate net photosynthesis? Implications from batch and continuous culture studies of marine phytoplankton

    Science.gov (United States)

    Pei, Shaofeng; Laws, Edward A.

    2013-12-01

    We carried out batch culture studies with seven species of marine phytoplankton and chemostat studies with two of the seven species to determine whether and to what extent 14C uptake approximated net photosynthesis. In two of seven cases, Isochrysis galbana and Dunaliella tertiolecta, cells uniformly labeled with 14C lost no activity when they were transferred to a 14C-free medium and allowed to grow in the light. In similar experiments with four other species, uniformly labeled cells lost activity when incubated in the light, but the loss rates were only a few percent per day. Thus these six species appear to respire primarily recently fixed carbon. In the case of the remaining species, Chlorella kessleri, loss rates of 14C in the light from uniformly labeled cells were about 29% per day, the apparent ratio of respiration to net photosynthesis being 0.4. Follow-up chemostat studies with I. galbana and C. kessleri grown under both light- and nitrate-limited conditions produced results consistent with the implications of the batch culture work: uptake of 14C by I. galbana after incubations of 24 h yielded estimates of photosynthetic carbon fixation equal to the product of the chemostat dilution rate and the concentration of organic carbon in the growth chamber. Similar experiments with C. kessleri produced 14C-based estimates of photosynthetic carbon fixation that exceeded the net rates of organic carbon production in the growth chamber by roughly 55%. Time-course studies with both species indicated that at high growth rates recently fixed carbon began to enter the respiratory substrate pool after a time lag of several hours, a result consistent with previous work with D. tertiolecta. The lag time appeared to be much shorter at low growth rates. The results with C. kessleri are similar to results previously reported for Chlorella pyrenoidosa and Amphidium carteri. Collectively these results suggest that 14C uptake by species with relatively high ratios of

  5. Fractionation and characterization of polysaccharides from cyanobacterium Spirulina (Arthrospira) maxima in nitrogen-limited batch culture

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    By a sequentially selective extraction procedure, polysaccharides (PS) from cyanobacterium Spirulina (Arthrospira) maxima that can be bio-functionally healthy components were fractionated in four parts including the culture medium (PSCM), the external layers of the cell (PSEL), the cell wall (PSCW) and storage granules (PSSG). The four fractionated parts of polysaccharides were characterized by gas-liquid chromatography (GLC) equipped with FID and fused-silica capillary column (15 m×0.53 mm i. d.). The contents of PSCM, PSEL, PSCW and PSSG were about 2.0%, 2.6%, 10.0% and 52.0% to cell dry matter, respectively. Glucose was almost the only monosaccharide in PSSG and PSCW and most predominant in PSEL, while in PSCM, xylose, rhamnose and glucose were the main ones. Two uronic acids represented by glucuronic acid and galacturoic acid, six neutral monosaccharides including fucose, rhamnose, xylose, mannose, galactose and glucose, and two possible unidentified sugars were found in PSEL and PSCM. These data are valuable for the selective productions of high-added value sugars from Spirulina.

  6. Characteristics of human cell line, F2N78, for the production of recombinant antibody in fed-batch and perfusion cultures.

    Science.gov (United States)

    Seo, Joon Serk; Min, Byung Sub; Kwon, Young-Bum; Lee, Soo-Young; Cho, Jong-Moon; Park, Keun-Hee; Yang, Yae Ji; Maeng, Ki Eun; Chang, Shin-Jae; Kim, Dong-Il

    2016-03-01

    A human hybrid cell line, F2N78, was developed by somatic fusion of HEK293 and Namalwa cells for the production recombinant biopharmaceutical proteins. In this study, we performed perfusion culture to verify its potential in culture process used for human cell expression platform. Cell viability could be maintained over 90% and high viable cell density was obtained at higher than 1.0 × 10(7) cells/mL by bleeding process in perfusion culture. The cells were adapted well in both culture modes, but there were apparent differences in protein quality. Compared to fed-batch culture, degalactosylated forms such as G0F and G0 as well as Man5 showed no significant increases in perfusion culture. In terms of charge variants, acidic peaks increased, whereas main peaks constantly decreased according to the length of culture period in both methods.

  7. Calcium transcriptionally regulates the biofilm machinery of Xylella fastidiosa to promote continued biofilm development in batch cultures.

    Science.gov (United States)

    Parker, Jennifer K; Chen, Hongyu; McCarty, Sara E; Liu, Lawrence Y; De La Fuente, Leonardo

    2016-05-01

    The functions of calcium (Ca) in bacteria are less characterized than in eukaryotes, where its role has been studied extensively. The plant-pathogenic bacterium Xylella fastidiosa has several virulence features that are enhanced by increased Ca concentrations, including biofilm formation. However, the specific mechanisms driving modulation of this feature are unclear. Characterization of biofilm formation over time showed that 4 mM Ca supplementation produced denser biofilms that were still developing at 96 h, while biofilm in non-supplemented media had reached the dispersal stage by 72 h. To identify changes in global gene expression in X. fastidiosa grown in supplemental Ca, RNA-Seq of batch culture biofilm cells was conducted at three 24-h time intervals. Results indicate that a variety of genes are differentially expressed in response to Ca, including genes related to attachment, motility, exopolysaccharide synthesis, biofilm formation, peptidoglycan synthesis, regulatory functions, iron homeostasis, and phages. Collectively, results demonstrate that Ca supplementation induces a transcriptional response that promotes continued biofilm development, while biofilm cells in nonsupplemented media are driven towards dispersion of cells from the biofilm structure. These results have important implications for disease progression in planta, where xylem sap is the source of Ca and other nutrients for X. fastidiosa. PMID:26913481

  8. Genetic Algorithmic Optimization of PHB Production by a Mixed Culture in an Optimally Dispersed Fed-batch Bioreactor

    Directory of Open Access Journals (Sweden)

    Pratap R. Patnaik

    2009-10-01

    Full Text Available Poly-β-hydroxybutyrate (PHB is an energy-storage polymer whose properties are similar to those of chemical polymers such as polyethylene and polypropylene. Moreover, PHB is biodegradable, absorbed by human tissues and less energy-consuming than synthetic polymers. Although Ralstonia eutropha is widely used to synthesize PHB, it is inefficient in utilizing glucose and similar sugars. Therefore a co-culture of R. eutropha and Lactobacillus delbrueckii is preferred since the latter can convert glucose to lactate, which R. eutropha can metabolize easily. Tohyama et al. [24] maximized PHB production in a well-mixed fed-batch bioreactor with glucose and (NH42SO4 as the primary substrates. Since production-scale bioreactors often deviate from ideal laboratory-scale reactors, a large bioreactor was simulated by means of a dispersion model with the kinetics determined by Tohyama et al. [24] and dispersion set at an optimum Peclet number of 20 [32]. The time-dependent feed rates of the two substrates were determined through a genetic algorithm (GA to maximize PHB production. This bioreactor produced 22.2% more PHB per liter and 12.8% more cell mass than achieved by Tohyama et al. [24]. These results, and similar observations with other fermentations, indicate the feasibility of enhancing the efficiency of large nonideal bioreactors through GA optimizations.

  9. Metabolic Control in Mammalian Fed-Batch Cell Cultures for Reduced Lactic Acid Accumulation and Improved Process Robustness

    Directory of Open Access Journals (Sweden)

    Viktor Konakovsky

    2016-01-01

    Full Text Available Biomass and cell-specific metabolic rates usually change dynamically over time, making the “feed according to need” strategy difficult to realize in a commercial fed-batch process. We here demonstrate a novel feeding strategy which is designed to hold a particular metabolic state in a fed-batch process by adaptive feeding in real time. The feed rate is calculated with a transferable biomass model based on capacitance, which changes the nutrient flow stoichiometrically in real time. A limited glucose environment was used to confine the cell in a particular metabolic state. In order to cope with uncertainty, two strategies were tested to change the adaptive feed rate and prevent starvation while in limitation: (i inline pH and online glucose concentration measurement or (ii inline pH alone, which was shown to be sufficient for the problem statement. In this contribution, we achieved metabolic control within a defined target range. The direct benefit was two-fold: the lactic acid profile was improved and pH could be kept stable. Multivariate Data Analysis (MVDA has shown that pH influenced lactic acid production or consumption in historical data sets. We demonstrate that a low pH (around 6.8 is not required for our strategy, as glucose availability is already limiting the flux. On the contrary, we boosted glycolytic flux in glucose limitation by setting the pH to 7.4. This new approach led to a yield of lactic acid/glucose (Y L/G around zero for the whole process time and high titers in our labs. We hypothesize that a higher carbon flux, resulting from a higher pH, may lead to more cells which produce more product. The relevance of this work aims at feeding mammalian cell cultures safely in limitation with a desired metabolic flux range. This resulted in extremely stable, low glucose levels, very robust pH profiles without acid/base interventions and a metabolic state in which lactic acid was consumed instead of being produced from day 1. With

  10. Robust optimization for nonlinear time-delay dynamical system of dha regulon with cost sensitivity constraint in batch culture

    Science.gov (United States)

    Yuan, Jinlong; Zhang, Xu; Liu, Chongyang; Chang, Liang; Xie, Jun; Feng, Enmin; Yin, Hongchao; Xiu, Zhilong

    2016-09-01

    Time-delay dynamical systems, which depend on both the current state of the system and the state at delayed times, have been an active area of research in many real-world applications. In this paper, we consider a nonlinear time-delay dynamical system of dha-regulonwith unknown time-delays in batch culture of glycerol bioconversion to 1,3-propanediol induced by Klebsiella pneumonia. Some important properties and strong positive invariance are discussed. Because of the difficulty in accurately measuring the concentrations of intracellular substances and the absence of equilibrium points for the time-delay system, a quantitative biological robustness for the concentrations of intracellular substances is defined by penalizing a weighted sum of the expectation and variance of the relative deviation between system outputs before and after the time-delays are perturbed. Our goal is to determine optimal values of the time-delays. To this end, we formulate an optimization problem in which the time delays are decision variables and the cost function is to minimize the biological robustness. This optimization problem is subject to the time-delay system, parameter constraints, continuous state inequality constraints for ensuring that the concentrations of extracellular and intracellular substances lie within specified limits, a quality constraint to reflect operational requirements and a cost sensitivity constraint for ensuring that an acceptable level of the system performance is achieved. It is approximated as a sequence of nonlinear programming sub-problems through the application of constraint transcription and local smoothing approximation techniques. Due to the highly complex nature of this optimization problem, the computational cost is high. Thus, a parallel algorithm is proposed to solve these nonlinear programming sub-problems based on the filled function method. Finally, it is observed that the obtained optimal estimates for the time-delays are highly satisfactory

  11. Novel micro-bioreactor high throughput technology for cell culture process development: Reproducibility and scalability assessment of fed-batch CHO cultures.

    Science.gov (United States)

    Amanullah, Ashraf; Otero, Jose Manuel; Mikola, Mark; Hsu, Amy; Zhang, Jinyou; Aunins, John; Schreyer, H Brett; Hope, James A; Russo, A Peter

    2010-05-01

    With increasing timeline pressures to get therapeutic and vaccine candidates into the clinic, resource intensive approaches such as the use of shake flasks and bench-top bioreactors may limit the design space for experimentation to yield highly productive processes. The need to conduct large numbers of experiments has resulted in the use of miniaturized high-throughput (HT) technology for process development. One such high-throughput system is the SimCell platform, a robotically driven, cell culture bioreactor system developed by BioProcessors Corp. This study describes the use of the SimCell micro-bioreactor technology for fed-batch cultivation of a GS-CHO transfectant expressing a model IgG4 monoclonal antibody. Cultivations were conducted in gas-permeable chambers based on a micro-fluidic design, with six micro-bioreactors (MBs) per micro-bioreactor array (MBA). Online, non-invasive measurement of total cell density, pH and dissolved oxygen (DO) was performed. One hundred fourteen parallel MBs (19 MBAs) were employed to examine process reproducibility and scalability at shake flask, 3- and 100-L bioreactor scales. The results of the study demonstrate that the SimCell platform operated under fed-batch conditions could support viable cell concentrations up to least 12 x 10(6) cells/mL. In addition, both intra-MB (MB to MB) as well as intra-MBA (MBA to MBA) culture performance was found to be highly reproducible. The intra-MB and -MBA variability was calculated for each measurement as the coefficient of variation defined as CV (%) = (standard deviation/mean) x 100. The % CV values for most intra-MB and intra-MBA measurements were generally under 10% and the intra-MBA values were slightly lower than those for intra-MB. Cell growth, process parameters, metabolic and protein titer profiles were also compared to those from shake flask, bench-top, and pilot scale bioreactor cultivations and found to be within +/-20% of the historical averages.

  12. Determination of some significant batch culture conditions affecting acetyl-xylan esterase production by Penicillium notatum NRRL-1249

    Directory of Open Access Journals (Sweden)

    Akhtar MN

    2011-05-01

    Full Text Available Abstract Background Acetyl-xylan esterase (AXE, EC 3.1.1.72 hydrolyses acetate group from the linear chain of xylopyranose residues bound by β-1,4-linkage. The enzyme finds commercial applications in bio-bleaching of wood pulp, treating animal feed to increase digestibility, processing food to increase clarification and converting lignocellulosics to feedstock and fuel. In the present study, we report on the production of an extracellular AXE from Penicillium notatum NRRL-1249 by solid state fermentation (SSF. Results Wheat bran at a level of 10 g (with 4 cm bed height was optimized as the basal substrate for AXE production. An increase in enzyme activity was observed when 7.5 ml of mineral salt solution (MSS containing 0.1% KH2PO4, 0.05% KCl, 0.05% MgSO4.7H2O, 0.3% NaNO3, 0.001% FeSO4.2H2O and 0.1% (v/w Tween-80 as an initial moisture content was used. Various nitrogen sources including ammonium sulphate, urea, peptone and yeast extract were compared for enzyme production. Maximal enzyme activity of 760 U/g was accomplished which was found to be highly significant (p ≤ 0.05. A noticeable enhancement in enzyme activity was observed when the process parameters including incubation period (48 h, initial pH (5, 0.2% (w/w urea as nitrogen source and 0.5% (v/w Tween-80 as a stimulator were further optimized using a 2-factorial Plackett-Burman design. Conclusion From the results it is clear that an overall improvement of more than 35% in terms of net enzyme activity was achieved compared to previously reported studies. This is perhaps the first report dealing with the use of P. notatum for AXE production under batch culture SSF. The Plackett-Burman model terms were found highly significant (HS, suggesting the potential commercial utility of the culture used (df = 3, LSD = 0.126.

  13. Dependence of morphology on agitation intensity in fed-batch cultures of Aspergillus oryzae and its implications for recombinant protein production.

    Science.gov (United States)

    Amanullah, A; Christensen, L H; Hansen, K; Nienow, A W; Thomas, C R

    2002-03-30

    We previously reported that, although agitation conditions strongly affected mycelial morphology, such changes did not lead to different levels of recombinant protein production in chemostat cultures of Aspergillus oryzae (Amanullah et al., 1999). To extend this finding to another set of operating conditions, fed-batch fermentations of A. oryzae were conducted at biomass concentrations up to 34 g dry cell weight/L and three agitation speeds (525, 675, and 825 rpm) to give specific power inputs between 1 and 5 kWm(-3). Gas blending was used to control the dissolved oxygen level at 50% of air saturation except at the lowest speed where it fell below 40% after 60-65 h. The effects of agitation intensity on growth, mycelial morphology, hyphal tip activity, and recombinant protein (amyloglucosidase) production in fed-batch cultures were investigated. In the batch phase of the fermentations, biomass concentration, and AMG secretion increased with increasing agitation intensity. If in a run, dissolved oxygen fell below approximately 40% because of inadequate oxygen transfer associated with enhanced viscosity, AMG production ceased. As with the chemostat cultures, even though mycelial morphology was significantly affected by changes in agitation intensity, enzyme titers (AGU/L) under conditions of substrate limited growth and controlled dissolved oxygen of >50% did not follow these changes. Although the measurement of active tips within mycelial clumps was not considered, a dependency of the specific AMG productivity (AGU/g biomass/h) on the percentage of extending tips was found, suggesting that protein secretion may be a bottle-neck in this strain during fed-batch fermentations. PMID:11835142

  14. Impact of the freeze-drying process on product appearance, residual moisture content, viability, and batch uniformity of freeze-dried bacterial cultures safeguarded at culture collections.

    Science.gov (United States)

    Peiren, Jindrich; Hellemans, Ann; De Vos, Paul

    2016-07-01

    In this study, causes of collapsed bacterial cultures in glass ampoules observed after freeze-drying were investigated as well as the influence of collapse on residual moisture content (RMC) and viability. Also, the effect of heat radiation and post freeze-drying treatments on the RMC was studied. Cake morphologies of 21 bacterial strains obtained after freeze-drying with one standard protocol could be classified visually into four major types: no collapse, porous, partial collapse, and collapse. The more pronounced the collapse, the higher residual moisture content of the freeze-dried product, ranging from 1.53 % for non-collapsed products to 3.62 % for collapsed products. The most important cause of collapse was the mass of the inserted cotton plug in the ampoule. Default cotton plugs with a mass between 21 and 30 mg inside the ampoule did not affect the viability of freeze-dried Aliivibrio fischeri LMG 4414(T) compared to ampoules without cotton plugs. Cotton plugs with a mass higher than 65 mg inside the ampoule induced a full collapsed product with rubbery look (melt-back) and decreasing viability during storage. Heat radiation effects in the freeze-drying chamber and post freeze-drying treatments such as exposure time to air after freeze-drying and manifold drying time prior to heat sealing of ampoules influenced the RMC of freeze-dried products. To produce uniform batches of freeze-dried bacterial strains with intact cake structures and highest viabilities, inserted cotton plugs should not exceed 21 mg per ampoule. Furthermore, heat radiation effects should be calculated in the design of the primary drying phase and manifold drying time before heat sealing should be determined as a function of exposure time to air.

  15. Probabilistic neural networks using Bayesian decision strategies and a modified Gompertz model for growth phase classification in the batch culture of Bacillus subtilis.

    Science.gov (United States)

    Simon; Nazmul Karim M

    2001-01-01

    Probabilistic neural networks (PNNs) were used in conjunction with the Gompertz model for bacterial growth to classify the lag, logarithmic, and stationary phases in a batch process. Using the fermentation time and the optical density of diluted cell suspensions, sampled from a culture of Bacillus subtilis, PNNs enabled a reliable determination of the growth phases. Based on a Bayesian decision strategy, the Gompertz based PNN used newly proposed definition of the lag and logarithmic phases to estimate the latent, logarithmic and stationary phases. This network topology has the potential for use with on-line turbidimeter for the automation and control of cultivation processes.

  16. Bacteriocin production by strain Lactobacillus delbrueckii ssp. bulgaricus BB18 during continuous prefermentation of yogurt starter culture and subsequent batch coagulation of milk.

    Science.gov (United States)

    Simova, E D; Beshkova, D M; Angelov, M P; Dimitrov, Zh P

    2008-06-01

    By screening for bacteriocin-producing lactic acid bacteria of 1,428 strains isolated from authentic Bulgarian dairy products, Lb. bulgaricus BB18 strain obtained from kefir grain was selected. Out of 11 yogurt starters containing Lb. bulgaricus BB18 and S. thermophilus strains resistant to bacteriocin secreted by Lb. bulgaricus BB18 a yogurt culture (S. thermophilus 11A+Lb. bulgaricus BB18) with high growth and bacteriocinogenic activity in milk was selected. Continuous (pH-stat 5.7) prefermentation processes were carried out in milk at 37 degrees C in a 2l MBR bioreactor (MBR AG, Zurich, Switzerland) with an IMCS controller for agitation speed, temperature, dissolved oxygen, CO2 and pH. Prefermented milk with pH 5.7 coagulated in a thermostat at 37 degrees C until pH 4.8-4.9. S. thermophilus 11A and Lb. bulgaricus BB18 grew independently in a continuous mode at similar and sufficiently high-dilution rates (D=1.83 h(-1)-S. thermophilus 11A; D=1.80 h(-1)-Lb. bulgaricus BB18). The yogurt cultures developed in a stream at a high-dilution rate (D=2.03-2.28 h(-1)). The progress of both processes (growth and bacteriocin production) depended on the initial ratio between the two microorganisms. The continuous prefermentation process promoted conditions for efficient fermentation and bacteriocinogenesis of the starter culture during the batch process: strong reduction of the times for bacteriocin production and coagulation of milk (to 4.5-5.0 h); high cell productivity (lactobacilli-4x10(12) CFU ml(-1), streptococci-6x10(12) CFU ml(-1)); high productivity of bacteriocins (4,500 BU ml(-1))-1.7 times higher than the bacteriocinogenic activity of the batch starter culture.

  17. Recombinant production of biologically active giant grouper (Epinephelus lanceolatus) growth hormone from inclusion bodies of Escherichia coli by fed-batch culture.

    Science.gov (United States)

    Chung, Wen-Jen; Huang, Chi-Lung; Gong, Hong-Yi; Ou, Tsung-Yin; Hsu, Jue-Liang; Hu, Shao-Yang

    2015-06-01

    Growth hormone (GH) performs important roles in regulating somatic growth, reproduction, osmoregulation, metabolism and immunity in teleosts, and thus, it has attracted substantial attention in the field of aquaculture application. Herein, giant grouper GH (ggGH) cDNA was cloned into the pET28a vector and expressed in Shuffle® T7 Competent Escherichia coli. Recombinant N-terminal 6× His-tagged ggGH was produced mainly in insoluble inclusion bodies; the recombinant ggGH content reached 20% of total protein. For large-scale ggGH production, high-cell density E. coli culture was achieved via fed-batch culture with pH-stat. After 30h of cultivation, a cell concentration of 41.1g/l dry cell weight with over 95% plasmid stability was reached. Maximal ggGH production (4.0g/l; 22% total protein) was achieved via mid-log phase induction. Various centrifugal forces, buffer pHs and urea concentrations were optimized for isolation and solubilization of ggGH from inclusion bodies. Hydrophobic interactions and ionic interactions were the major forces in ggGH inclusion body formation. Complete ggGH inclusion body solubilization was obtained in PBS buffer at pH 12 containing 3M urea. Through a simple purification process including Ni-NTA affinity chromatography and refolding, 5.7mg of ggGH was obtained from 10ml of fed-batch culture (45% recovery). The sequence and secondary structure of the purified ggGH were confirmed by LC-MS/MS mass spectrometry and circular dichroism analysis. The cell proliferation-promoting activity was confirmed in HepG2, ZFL and GF-1 cells with the WST-1 colorimetric bioassay. PMID:25703054

  18. Lactic acid production from a mixture of cultures of Lactococcus lactis and Streptococcus salivarius using batch fermentation

    Directory of Open Access Journals (Sweden)

    Liliana Serna Cock

    2006-12-01

    Full Text Available Production of lactic acid (LA, yield (Yp/s and substrate conversion (SC from Lactococcus lactis, Streptococcus salivarius and their mixtures were tested. Lactococcus lactis was selected from 20 homofermentative strains isolated from a sugar cane crop (variety CC85-92 and Streptococcus salivarius was isolated from a commercial lactic ferment. Batch fermentation experiments at 32 C with a glucose concentration of 60 gL-1 and a pH of 6,0 were carried out. A maximum of 47,63 gL-1 of lactic acid concentration, 95,4% of substrate conversion and 83 gg-1 were obtained from the mixture of strains after a fermentation of 48 h. Key words: sugar cane, Lactococcus lactis, Streptococcus salivarius, mixture of strains.

  19. Two parametric cell cycle analyses of plant cell suspension cultures with fragile, isolated nuclei to investigate heterogeneity in growth of batch cultivations.

    Science.gov (United States)

    Haas, Christiane; Hegner, Richard; Helbig, Karsten; Bartels, Kristin; Bley, Thomas; Weber, Jost

    2016-06-01

    Plant cell suspensions are frequently considered to be heterogeneous with respect to growth in terms of progression of the cells through the cell cycle and biomass accumulation. Thus, segregated data of fractions in different cycle phases during cultivation is needed to develop robust production processes. Bromodeoxyuridine (BrdU) incorporation and BrdU-antibodies or 5-ethynyl-2'-deoxyuridine (EdU) click-it chemistry are frequently used to acquire such information. However, their use requires centrifugation steps that cannot be readily applied to sensitive cells, particularly if nuclei have to be extracted from the protective cellular milieu and envelopes for DNA analysis. Therefore, we have established a BrdU-Hoechst stain quenching protocol for analyzing nuclei directly isolated from delicate plant cell suspension cultures. After adding BrdU to test Harpagophytum procumbens cell suspension cultures the cell cycle distribution could be adequately resolved using its incorporation for the following 72 h (after which BrdU slowed biomass accumulation). Despite this limitation, the protocol allows resolution of the cell cycle distribution of cultures that cannot be analyzed using commonly applied methods due to the cells' fragility. The presented protocol enabled analysis of cycling heterogeneities in H. procumbens batch cultivations, and thus should facilitate process control of secondary metabolite production from fragile plant in vitro cultures. Biotechnol. Bioeng. 2016;113: 1244-1250. © 2015 Wiley Periodicals, Inc. PMID:26614913

  20. Utilising bacterial communities associated with digested piggery effluent as a primary food source for the batch culture of Moina australiensis.

    Science.gov (United States)

    Patil, Sayali S; Ward, Andrew J; Kumar, Martin S; Ball, Andrew S

    2010-05-01

    In this study, a cladoceran planktonic invertebrate, Moina australiensis was uniquely cultured in two stage digested piggery wastewater and fed associated piggery wastewater bacteria. The viability of M. australiensis cultured in digested piggery wastewater under closed dark conditions to limit phytoplankton activity was tested by determining suitable effluent total ammonia nitrogen (TAN) concentrations. The highest total M. australiensis biomass production 0.94+/-0.47g and the rate of population increase (r) 0.15+/-0.08 was recorded in the 30mgl(-1) TAN concentration treatment. The lowest 'r' values and decreased biomass production was observed with increasing TAN concentration levels. This study, also focused on profiling and quantification of the associated bacterial populations in the wastewater culture media and within the digestive tract of M. australiensis by denaturing gradient gel electrophoresis (DGGE) and real-time polymerase chain reaction (RT-PCR) which revealed the feeding specificity of M. australiensis towards "gamma-Proteobacteria." PMID:20089398

  1. A novel fed-batch based cultivation method provides high cell-density and improves yield of soluble recombinant proteins in shaken cultures

    Directory of Open Access Journals (Sweden)

    Glumoff Tuomo

    2010-02-01

    Full Text Available Abstract Background Cultivations for recombinant protein production in shake flasks should provide high cell densities, high protein productivity per cell and good protein quality. The methods described in laboratory handbooks often fail to reach these goals due to oxygen depletion, lack of pH control and the necessity to use low induction cell densities. In this article we describe the impact of a novel enzymatically controlled fed-batch cultivation technology on recombinant protein production in Escherichia coli in simple shaken cultures. Results The enzymatic glucose release system together with a well-balanced combination of mineral salts and complex medium additives provided high cell densities, high protein yields and a considerably improved proportion of soluble proteins in harvested cells. The cultivation method consists of three steps: 1 controlled growth by glucose-limited fed-batch to OD600 ~10, 2 addition of growth boosters together with an inducer providing efficient protein synthesis within a 3 to 6 hours period, and 3 a slow growth period (16 to 21 hours during which the recombinant protein is slowly synthesized and folded. Cell densities corresponding to 10 to 15 g l-1 cell dry weight could be achieved with the developed technique. In comparison to standard cultures in LB, Terrific Broth and mineral salt medium, we typically achieved over 10-fold higher volumetric yields of soluble recombinant proteins. Conclusions We have demonstrated that by applying the novel EnBase® Flo cultivation system in shaken cultures high cell densities can be obtained without impairing the productivity per cell. Especially the yield of soluble (correctly folded proteins was significantly improved in comparison to commonly used LB, Terrific Broth or mineral salt media. This improvement is thought to result from a well controlled physiological state during the whole process. The higher volumetric yields enable the use of lower culture volumes and can

  2. Key Process Conditions for Production of C4 Dicarboxylic Acids in Bioreactor Batch Cultures of an Engineered Saccharomyces cerevisiae Strain

    NARCIS (Netherlands)

    Zelle, R.M.; De Hulster, E.; Kloezen, W.; Pronk, J.T.; Van Maris, A.J.A.

    2009-01-01

    A recent effort to improve malic acid production by Saccharomyces cerevisiae by means of metabolic engineering resulted in a strain that produced up to 59 g liter−1 of malate at a yield of 0.42 mol (mol glucose)−1 in calcium carbonate-buffered shake flask cultures. With shake flasks, process paramet

  3. Key Process Conditions for Production of C4 Dicarboxylic Acids in Bioreactor Batch Cultures of an Engineered Saccharomyces cerevisiae Strain

    NARCIS (Netherlands)

    Zelle, R.M.; De Hulster, E.; Kloezen, W.; Pronk, J.T.; Van Maris, A.J.A.

    2010-01-01

    A recent effort to improve malic acid production by Saccharomyces cerevisiae by means of metabolic engineering resulted in a strain that produced up to 59 g liter(-1) of malate at a yield of 0.42 mol (mol glucose)(-1) in calcium carbonate-buffered shake flask cultures. With shake flasks, process par

  4. Microarray-based MALDI-TOF mass spectrometry enables monitoring of monoclonal antibody production in batch and perfusion cell cultures.

    Science.gov (United States)

    Steinhoff, Robert F; Karst, Daniel J; Steinebach, Fabian; Kopp, Marie R G; Schmidt, Gregor W; Stettler, Alexander; Krismer, Jasmin; Soos, Miroslav; Pabst, Martin; Hierlemann, Andreas; Morbidelli, Massimo; Zenobi, Renato

    2016-07-15

    Cell culture process monitoring in monoclonal antibody (mAb) production is essential for efficient process development and process optimization. Currently employed online, at line and offline methods for monitoring productivity as well as process reproducibility have their individual strengths and limitations. Here, we describe a matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS)-based on a microarray for mass spectrometry (MAMS) technology to rapidly monitor a broad panel of analytes, including metabolites and proteins directly from the unpurified cell supernatant or from host cell culture lysates. The antibody titer is determined from the intact antibody mass spectra signal intensity relative to an internal protein standard spiked into the supernatant. The method allows a semi-quantitative determination of light and heavy chains. Intracellular mass profiles for metabolites and proteins can be used to track cellular growth and cell productivity. PMID:26707204

  5. Cultural, Transcriptomic, and Proteomic Analyses of Water-Stressed Cells of Actinobacterial Strains Isolated from Compost: Ecological Implications in the Fed-Batch Composting Process.

    Science.gov (United States)

    Narihiro, Takashi; Kanosue, Yuji; Hiraishi, Akira

    2016-06-25

    This study was undertaken to examine the effects of water activity (aw) on the viability of actinobacterial isolates from a fed-batch composting (FBC) process by comparing culturability and stainability with 5-cyano-2,3-ditoryl tetrazolium chloride (CTC). The FBC reactor as the source of these bacteria was operated with the daily loading of household biowaste for 70 d. During this period of composting, aw in the reactor decreased linearly with time and reached approximately 0.95 at the end of operation. The plate counts of aerobic chemoorganotrophic bacteria were 3.2-fold higher than CTC-positive (CTC+) counts on average at the fully acclimated stage (after 7 weeks of operation), in which Actinobacteria predominated, as shown by lipoquinone profiling and cultivation methods. When the actinobacterial isolates from the FBC process were grown under aw stress, no significant differences were observed in culturability among the cultures, whereas CTC stainability decreased with reductions in aw levels. A cDNA microarray-based transcriptomic analysis of a representative isolate showed that many of the genes involved in cellular metabolism and genetic information processing were down-regulated by aw stress. This result was fully supported by a proteomic analysis. The results of the present study suggest that, in low aw mature compost, the metabolic activity of the community with Actinobacteria predominating is temporarily reduced to a level that hardly reacts with CTC; however, these bacteria are easily recoverable by exposure to a high aw culture medium. This may be a plausible reason why acclimated FBC reactors in which Actinobacteria predominate yields higher plate counts than CTC+ counts. PMID:27246805

  6. H(2) production through anaerobic mixed culture: effect of batch S(0)/X(0) and shock loading in CSTR.

    Science.gov (United States)

    Fan, Kuo-Shuh; Chen, Ya-Yun

    2004-12-01

    Biological production of H(2) has received considerable attention lately. The present study was undertaken to observe the effects of substrate/seeding ratios (S(0)/X(0)) on batch H(2) generation. The H(2)-producing seeding spores were obtained from the heat treatment (88 degrees C for 12h) of the compost from a grass composting facility. A dehydrated brewery mixture was used as feed substrate. The results indicate that the pattern of the cumulative H(2) production with time is similar to the growth curve with a typical lag, exponential and stationary phase; the results were successfully modeled with a modified Gompertz equation. It appears that maximum H(2) yield potential (27ml g(-1)COD(added)) occurs at an S(0)/X(0) ratio of about 4, whereas the maximum specific H(2) yield (205ml g(-1) VSSd(-1)) occurs at approximately S(0)/X(0)=3. The S(0)/X(0) ratios higher than 4 would inhibit H(2) production. An attempt was made to waste a certain amount of reactor content and replaced it with fresh substrate in order to enhance H(2) production. After this medium replacement, the H(2) production was initially inhibited and the system then exhibited a long lag before it reached an active H(2) production stage. For a continuous-stirred tank-reactor (CSTR) system, the results of replacing 25% of the reactor content indicate that there is still a lag time before a sudden increase in H(2) production after the addition of the new substrate feed. The major low molecular weight acids identified are HAc and HBu with total volatile acids of about 6000-8000mg l(-1). The ratio of HAc/HBu in the present study is relatively constant (about 5) and appears not significantly affected by the medium replacement. The concentration of total alcohols is about 2000mg l(-1). All in all, the CSTR system is able to recover to its previous performance after such a dramatic 25% medium replacement.

  7. Production of Gymnemic Acid Depends on Medium, Explants, PGRs, Color Lights, Temperature, Photoperiod, and Sucrose Sources in Batch Culture of Gymnema sylvestre

    Directory of Open Access Journals (Sweden)

    A. Bakrudeen Ali Ahmed

    2012-01-01

    Full Text Available Gymnema sylvestre (R.Br. is an important diabetic medicinal plant which yields pharmaceutically active compounds called gymnemic acid (GA. The present study describes callus induction and the subsequent batch culture optimization and GA quantification determined by linearity, precision, accuracy, and recovery. Best callus induction of GA was noticed in MS medium combined with 2,4-D (1.5 mg/L and KN (0.5 mg/L. Evaluation and isolation of GA from the calluses derived from different plant parts, namely, leaf, stem and petioles have been done in the present case for the first time. Factors such as light, temperature, sucrose, and photoperiod were studied to observe their effect on GA production. Temperature conditions completely inhibited GA production. Out of the different sucrose concentrations tested, the highest yield (35.4 mg/g d.w was found at 5% sucrose followed by 12 h photoperiod (26.86 mg/g d.w. Maximum GA production (58.28 mg/g d.w was observed in blue light. The results showed that physical and chemical factors greatly influence the production of GA in callus cultures of G. sylvestre. The factors optimized for in vitro production of GA during the present study can successfully be employed for their large-scale production in bioreactors.

  8. Dynamic model-based analysis of furfural and HMF detoxification by pure and mixed batch cultures of S. cerevisiae and S. stipitis.

    Science.gov (United States)

    Hanly, Timothy J; Henson, Michael A

    2014-02-01

    Inhibitory compounds that result from biomass hydrolysis are an obstacle to the efficient production of second-generation biofuels. Fermentative microorganisms can reduce compounds such as furfural and 5-hydroxymethyl furfural (HMF), but detoxification is accompanied by reduced growth rates and ethanol yields. In this study, we assess the effects of these furan aldehydes on pure and mixed yeast cultures consisting of a respiratory deficient mutant of Saccharomyces cerevisiae and wild-type Scheffersomyces stipitis using dynamic flux balance analysis. Uptake kinetics and stoichiometric equations for the intracellular reduction reactions associated with each inhibitor were added to genome-scale metabolic reconstructions of the two yeasts. Further modification of the S. cerevisiae metabolic network was necessary to satisfactorily predict the amount of acetate synthesized during HMF reduction. Inhibitory terms that captured the adverse effects of the furan aldehydes and their corresponding alcohols on cell growth and ethanol production were added to attain qualitative agreement with batch experiments conducted for model development and validation. When the two yeasts were co-cultured in the presence of the furan aldehydes, inoculums that reduced the synthesis of highly toxic acetate produced by S. cerevisiae yielded the highest ethanol productivities. The model described here can be used to generate optimal fermentation strategies for the simultaneous detoxification and fermentation of lignocellulosic hydrolysates by S. cerevisiae and/or S. stipitis.

  9. Improved elastase production by Bacillus sp.EL31410--further optimization and kinetics studies of culture medium for batch fermentation

    Institute of Scientific and Technical Information of China (English)

    何国庆; 陈启和; 琚晓捷; 石乃冬

    2004-01-01

    An efficient culture medium producing a bacterial elastase with high yields was developed further following preliminary studies by means of response surface method. Central composite design (CCD) and response surface methodology were applied to optimize the medium constituents. A central composite design was used to explain the combined effect of three medium constituents, viz, glucose, K2HPO4, MgSO4@7H2O. The strain produced more elastase in the completely optimized medium, as compared with the partially optimized medium. The fitted model of the second model, as per RSM,showed that glucose was 7.4 g/100 ml, casein 1.13 g/100 ml, corn steep flour 0.616 g/100 ml, K2HPO4 0.206 g/100 ml and MgSO4@7H2O 0.034 g/100 ml. The fermentation kinetics of these two culture media in the flask experiments were analyzed. It was found that the highest elastase productivity occurred at 54 hours. Higher glucose concentration had inhibitory effect on elastase production. At the same time, we observed that the glucose consumption rate was slow in the completely optimized medium, which can explain the lag period of the highest elastase production. Some metal ions and surfactant additives also affected elastase production and cell growth.

  10. Evaluation on prebiotic properties of β-glucan and oligo-β-glucan from mushrooms by human fecal microbiota in fecal batch culture

    Directory of Open Access Journals (Sweden)

    Chiraphon Chaikliang

    2015-11-01

    Full Text Available Background: β-glucan is dietary fiber, a structural polysaccharide, β-linked linear chains of D-glucose polymers with variable frequency of branches. β-glucan is isolated from different sources such as cell walls of baker’s yeast (Saccharomyces cerevisiae, cereals (oat and barley and various species of mushrooms. Among 8 mushrooms in the study, Schizophylum commune Fr and Auricularia auricula Judae had the highest in β-glucan contents and the cheapest cost of mushroom per content of β-glucan, respectively. Even the function of β-glucan on immune modulation has been known however no report on interaction between β-glucan and human gut microbiota. Gut microbiota is thought to have health effects by interaction with non-digestible component particular fermentable dietary fiber. It is important to correlate the specific groups of the microbial communities associated with β-glucan fermentation and the consequential SCFA profiles. β-glucan from mushroom may has potential prebiotic function similar to those from commercial yeast (Saccharomyces cerevisiae β-glucan. Objective: To evaluate on prebiotic properties of soluble β-glucans and oligo-β-glucans from Schizophylum commune Fr and Auricularia auricula Judae by fecal fermentation in batch culture. Methods: In vitro fecal fermentation in anaerobic batch cultures under simulated conditions similar to human colon with human faecal samples from three donors were performed. Comparison on 3 β-glucans and 2 oligo-β-glucans have been studied. Sample was taken at 0 h, 24 h and 48 h to analyze the numbers of bacterial changes by fluorescent in situ hybridization (FISH technique. Short chain fatty acids (SCFA were analyzed by HPLC. The prebiotic index (PI was calculated according to the change of 5 specific bacterial genus within 48 h fermentation. Results: Soluble β-glucan from Auricularia auricula Judae increased numbers of bifidobacteria and lactobacillus significantly (P<0.05. The PI of

  11. Viral and bacterial production in the North Water: in situ measurements, batch-culture experiments and characterization and distribution of a virus host system

    Science.gov (United States)

    Middelboe, Mathias; Nielsen, Torkel G.; Bjørnsen, Peter K.

    Growth and viral lysis of bacterioplankton at subzero temperatures were measured in the North Water polynya in July 1998. In situ measurements of bacterial carbon consumption in surface waters ranged from 15 to 63 μg C l -1 d -1 in the eastern and 6 to 7 μg C l -1 d -1 in the northern part of the polynya. Both bacterial abundance and activity appeared to increase in response to the decay of the phytoplankton bloom that developed in the North Water. Organic carbon was the limiting substrate for bacteria in the polynya since addition of glucose, but not inorganic nutrients, to batch cultures increased both the carrying capacity of the substrate and the growth rate of the bacteria. Bacterial growth rates ranged from 0.11 to 0.40 d -1, corresponding to bacterial generation times of 1.7-6.3 d. The in situ viral production rate was estimated both from the frequency of visibly infected cells and from the rate of viral production in batch cultures; it ranged from 0.04 to 0.52 d -1 and from 0.25 to 0.47 d -1, respectively. From 6% to 28% of bacterial production was found to be lost due to viral lysis. The average virus-bacteria ratio was 5.1±3.1, with the abundance of viruses being correlated positively with bacterial production. A Pseudoalteromonas sp. bacterial host and an infective virus were isolated from the polynya; characteristics and distribution of the virus-host system were examined. The Pseudoalteromonas sp. showed psychrotolerant growth and sustained significant production of viruses at 0°C. The virus-host system was found throughout the polynya. Overall the results suggested that a large amount of organic carbon released during the development and breakdown of the spring phytoplankton bloom was consumed by planktonic bacteria and that the microbial food web was an important and dynamic component of the planktonic food web in the North Water.

  12. Detection of Sialic Acid-Utilising Bacteria in a Caecal Community Batch Culture Using RNA-Based Stable Isotope Probing

    Directory of Open Access Journals (Sweden)

    Wayne Young

    2015-03-01

    Full Text Available Sialic acids are monosaccharides typically found on cell surfaces and attached to soluble proteins, or as essential components of ganglioside structures that play a critical role in brain development and neural transmission. Human milk also contains sialic acid conjugated to oligosaccharides, glycolipids, and glycoproteins. These nutrients can reach the large bowel where they may be metabolised by the microbiota. However, little is known about the members of the microbiota involved in this function. To identify intestinal bacteria that utilise sialic acid within a complex intestinal community, we cultured the caecal microbiota from piglets in the presence of 13C-labelled sialic acid. Using RNA-based stable isotope probing, we identified bacteria that consumed 13C-sialic acid by fractionating total RNA in isopycnic buoyant density gradients followed by 16S rRNA gene analysis. Addition of sialic acid caused significant microbial community changes. A relative rise in Prevotella and Lactobacillus species was accompanied by a corresponding reduction in the genera Escherichia/Shigella, Ruminococcus and Eubacterium. Inspection of isotopically labelled RNA sequences suggests that the labelled sialic acid was consumed by a wide range of bacteria. However, species affiliated with the genus Prevotella were clearly identified as the most prolific users, as solely their RNA showed significantly higher relative shares among the most labelled RNA species. Given the relevance of sialic acid in nutrition, this study contributes to a better understanding of their microbial transformation in the intestinal tract with potential implications for human health.

  13. Response coefficient analysis of a fed-batch bioreactor to dissolved oxygen perturbation in complementary cultures during PHB production

    Directory of Open Access Journals (Sweden)

    Patnaik Pratap R

    2008-03-01

    Full Text Available Abstract Background Although the production of poly-β-hydroxybutyrate (PHB has many biological, energetic and environmental advantages over chemically synthesized polymers, synthetic polymers continue to be produced industrially since the productivities of fermentation processes fr PHB are not yet economically competitive. Improvement of a PHB fermentation requires good understanding and optimization under the realistic conditions of large bioreactors. Laboratory-scale studies have shown that co-cultures of Ralstonia eutropha and Lactobacillus delbrueckii generate better fermentation efficiencies than R. eutropha alone. In large bioreactors, incomplete dispersioin and perturbations in the dissolved oxygen (DO concentration, both of which affect the fermentation, have to be considered. This study analyzes the effect of DO fluctuations on bioreactor performance for both ideal and optimally dispersed broths. Results Response coefficient analysis was employed to obtain quantitative information on the effect of DO perturbations on different variables. Three values of the Peclet number (Pe cheracterized three levels of dispersion: Pe = 0.01 for nearly complete dispersion, Pe = 20 for optimum dispersion and Pe = 60 for insufficient dispersion. The response coefficients (RCs of the pairs of bacterial concentrations and the main substrates, glucose and ammonium chloride, showed contrasting variations with time. Lactate, a critical intermediate, and PHB had similar RC profiles but those of lactate were one to two orders of magnitude larger than other RCs. Significantly, the optimum Pe also resulted in the largest RCs, suggesting a balance between productivity and reactor stability. Conclusion Since R. eutropha requires oxygen for its growth whereas L. delbrueckii does not, fluctuations in the DO concentartion have a strong influence on the fermentation. Apart from this, the mechanism of PHB biosynthesis indicates that control of lactate is a critical

  14. Industrial textile effluent decolourization in stirred and static batch cultures of a new fungal strain Chaetomium globosum IMA1 KJ472923.

    Science.gov (United States)

    Manai, Imène; Miladi, Baligh; El Mselmi, Abdellatif; Smaali, Issam; Ben Hassen, Aida; Hamdi, Moktar; Bouallagui, Hassib

    2016-04-01

    The treatment of an industrial textile effluent (ITE) was investigated by using a mono-culture of a novel fungal strain Chaetomium globosum IMA1. This filamentous fungus was selected based on its capacity for dye removal via the biodegradation mechanism. The respirometric analysis showed that C. globosum IMA1 was resistant to an indigo concentration up to 700 mg equivalent COD/L. The decolourization of the ITE by C. globosum was performed in static and stirred batch systems. The better lignin peroxidase (LiP), laccase and the manganese peroxidase (MnP) productions were 829.9 U/L, 83 U/L and 247.8 U/L, respectively since 3-5 days under a stirred condition. Therefore, the chemical oxygen demand (COD) and colors (OD620) removal yields reached 88.4% and 99.8%, respectively. Fourier transforms infrared spectroscopy (FTIR) analysis of the treated effluent showed that the decolourization was due to the degradation and the transformation of dye molecules. However, spectrophotometric examination showed that the complete dye removal was through fungal adsorption (8%), followed by degradation (92%). PMID:26775156

  15. Industrial textile effluent decolourization in stirred and static batch cultures of a new fungal strain Chaetomium globosum IMA1 KJ472923.

    Science.gov (United States)

    Manai, Imène; Miladi, Baligh; El Mselmi, Abdellatif; Smaali, Issam; Ben Hassen, Aida; Hamdi, Moktar; Bouallagui, Hassib

    2016-04-01

    The treatment of an industrial textile effluent (ITE) was investigated by using a mono-culture of a novel fungal strain Chaetomium globosum IMA1. This filamentous fungus was selected based on its capacity for dye removal via the biodegradation mechanism. The respirometric analysis showed that C. globosum IMA1 was resistant to an indigo concentration up to 700 mg equivalent COD/L. The decolourization of the ITE by C. globosum was performed in static and stirred batch systems. The better lignin peroxidase (LiP), laccase and the manganese peroxidase (MnP) productions were 829.9 U/L, 83 U/L and 247.8 U/L, respectively since 3-5 days under a stirred condition. Therefore, the chemical oxygen demand (COD) and colors (OD620) removal yields reached 88.4% and 99.8%, respectively. Fourier transforms infrared spectroscopy (FTIR) analysis of the treated effluent showed that the decolourization was due to the degradation and the transformation of dye molecules. However, spectrophotometric examination showed that the complete dye removal was through fungal adsorption (8%), followed by degradation (92%).

  16. Fed-batch culture of Saccharomyces cerevisiae in sugar-cane blackstrap molasses: invertase activity of intact cells in ethanol fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Echegaray, O.F.; Carvalho, J.C.M.; Fernandes, A.N.R.; Sato, S.; Aquarone, E.; Vitolo, M. [University of Sao Paulo, (Brazil). Department of Biochemical and Pharmaceutical Technology

    2000-07-01

    Fed-batch cultures of Saccharomyces cerevisiae were carried out in a 14 l fermenter (NBS, Microferm), containing sugar-cane blackstrap molasses supplemented with urea (0.5 g l{sup -1}) and penicillin V (500 ui/l), under the following conditions: 32({+-}1) deg C; pH 4.5 - 5.0; N = 200 min{sup -1}; inoculum and mash volume equal to 3.0 l and 7.0 l, respectively. The parameters varied were: filling time (T: 1, 2 or 3 h), time constant (K: 0, 0.8 or 1.6 h{sup -1}), total reducing sugar concentration in the feeding mash (S{sub m}) (170, 220 or 270 g l{sup -1}) and total amount of wet-pressed yeast in the inoculum (M{sub x0}') (800, 1300 or 1800 g). By applying the quadratic regression analysis the following equations were established: Y = 78.2 + 2.5X{sub 3} + 2.5(X{sub 3}){sup 2} - 3.3X{sub 4} - 0.89X{sub 1},X{sub 2} - 0.79X{sub 3},X{sub 4} and P{sub v} = 71.3 + 6.5X{sub 4} - 4.9X{sub 2},X{sub 4} for the ethanol yield (Y) and residual invertase activity (P{sub v}), respectively. The optimised ethanol and invertase formation was observed for high S{sub m} values under low M{sub x0}' - and high K. (author)

  17. Pro Spring Batch

    CERN Document Server

    Minella, Michael T

    2011-01-01

    Since its release, Spring Framework has transformed virtually every aspect of Java development including web applications, security, aspect-oriented programming, persistence, and messaging. Spring Batch, one of its newer additions, now brings the same familiar Spring idioms to batch processing. Spring Batch addresses the needs of any batch process, from the complex calculations performed in the biggest financial institutions to simple data migrations that occur with many software development projects. Pro Spring Batch is intended to answer three questions: *What? What is batch processing? What

  18. Regulation of Autotrophic and Heterotrophic Metabolism in Pseudomonas oxalaticus OX1. Growth on Fructose and on Mixtures of Fructose and Formate in Batch and Continuous Cultures

    NARCIS (Netherlands)

    Dijkhuizen, L.; Harder, W.

    1984-01-01

    In Pseudomonas oxalaticus the synthesis of enzymes involved in autotrophic CO2 fixation via the Calvin cycle is regulated by repression/derepression. During growth of the organism on fructose alone, the synthesis of ribulosebisphosphate carboxylase (RuBPCase) remained fully repressed, both in batch

  19. 红曲霉色素流加培养的初步研究%Preliminary Study on Fed-batch Culture of Monascus Pigments

    Institute of Scientific and Technical Information of China (English)

    杨旭; 曹岚; 李旭

    2013-01-01

    Objective:The optimization methods of monascus pigments with submerged fermentation are studied.The level of fermentation is improved and the products contain a high concentration of monascus pigments.Methods:L8 (27) orthogonal experiment and fed-batch fermentation method of monaseus purpureus liquid are designed to select the most efficient fermentation medium for monaseus purpureus,reduce inhibition caused by over-rich nutrients and improve the fermentation concentration and level through different batch fermentation modes.Conclusion:Optimized shake flask fermentation medium with maltose of 8°Bx,soluble starch of 3%,soya bean protein powder of 4%,NaCl of 0.5%,magnesium sulfate of 0.05% and dipotassium hydrogen phosphate of 0.1%.The optimum fed-batch mode is obtained by fed-batch fermentation for 2 L batch tank,the best feeding submerged fermentation starts feeding after 60 h,filling every 20 min,completes after 12 h.Compared with batch fermentation,the valence of fed-batch fermented monascus pigment increases by 57%.%目的:研究红曲霉液体深层发酵的优化方法,提高其发酵水平,生产出含有较高红曲霉色素的产品.方法:采用L8(27)正交实验法和红曲霉液体流加发酵方法,通过不同的补料发酵方式,降低营养物质过浓而产生的阻碍作用,提高发酵浓度和水平.结果:优化后的培养基为饴糖8°Bx,可溶淀粉3%,大豆蛋白粉4%,氯化钠0.5%,硫酸镁0.05%,磷酸氢二钾0.1%.通过对2L发酵罐的补料发酵得出最佳的补料方式:液体深层发酵60 h以后开始补料,每20 min补1次,12 h补完,同分批发酵相比,流加发酵红曲色素的效价提高57%.

  20. Kinetics of High Cell Density Fed-batch Culture of Recombinant Escherichia coli Producing Human-like Collagen%重组大肠杆菌分批-补料高密度发酵生产类人胶原蛋白的动力学

    Institute of Scientific and Technical Information of China (English)

    花秀夫; 范代娣; 骆艳娥; 张兮; 施惠娟; 米钰; 马晓轩; 尚龙安; 赵桂仿

    2006-01-01

    The kinetics of batch and fed-batch cultures of recombinant Escherichia coli producing human-like collagen was investigated. In the batch culture, a kinetic model of a simple growth-association system was concluded without consideration of cell endogeneous metabolism. The cell lag time, the maximum specific growth rate and growth rates were set at (0.15, 0.2, 0.25h-1) by the method of pseudo-exponential feeding, and the expressions for the specific rate of substrate consumption, the growth kinetics and the product formation kinetics of each phase spectively. The model predictions are in good agreement with the experimental data.

  1. On-line monitoring of important organoleptic methyl-branched aldehydes during batch fermentation of starter culture Staphylococcus xylosus reveal new insight into their production in a model fermentation

    DEFF Research Database (Denmark)

    de Vos Petersen, Christian; Beck, Hans Christian; Lauritsen, Frants R

    2004-01-01

    of a longer aerobic growth period. Growing S. xylosus under conditions resembling those in a fermented sausage revealed that NaCl (5%) increased aldehyde production considerably, whereas KNO(3) (0.03%) or NaNO(2) (0.03%) had little effect. A lowering of pH from 7.2 to 6.0 reduced cell density, but had a minor......A small fermentor (55 mL) was directly interfaced to a membrane inlet mass spectrometer for continuous on-line monitoring of oxygen and volatile metabolites during batch fermentations of the starter culture Staphylococcus xylosus. Using this technique, we were able to correlate production...

  2. 分批补料及缺氮培养对小球藻油脂产量的影响%Effects of Fed-batch and Nitrogen-deficient Culture on Lipid Yield of Chlorella sp.

    Institute of Scientific and Technical Information of China (English)

    葛珍珍; 王杰; 余晓斌

    2012-01-01

    目的 为了实现小球藻的高密度及高产油培养。方法 通过分析分批培养过程中藻细胞的生长曲线,葡萄糖消耗曲线,pH及溶氧变化曲线,以小球藻进行分批补料,待藻细胞达到一定的高密度后再进行缺氮培养以富集细胞内的油脂。结果 经过4次分批补料,小球藻的生物量达到了65.25g/L,然后进行缺氮培养12h,然后进行缺氮培养12h,小球藻的油脂含量由42.75%提高到63.82%,油脂含量达43.47g/L.结论 合理的分批补料明显地提高了小球藻的生物量。缺氮培养进一步提高了小球藻的油脂含量。%[Objective] This study was to realize high-density culture of Chlorella sp. as well as the culture with high lipid yield. [Method] Through analyzing the growth curve of Chlorella sp. cells, dextrose consumption curve, change curves of pH and dissolved oxygen, a fed-batch culture was conducted, followed by a nitrogen-deficient culture aiming at accumulating the lipids in Chlorella sp. cells when a high density of Chlorella sp. cells was obtained. [Result] After four batches of feeding were pro- vided, the biomass of Chlorella sp. reached up to 65.25 g/L, and the lipid content increased from 42.75% to 63.82% in Chlorella sp. cells, with the yield of 43.37 g/L in the following 12 hours of nitrogen-deficient culture. [Conclusion] Reasonable fed- batch can significantly improve the biomass of Chlorella sp., and the nitrogen-defi- cient culture further raises the lipid yield of Chlorella sp.

  3. Variação da composição química do meio de cultura e da bioquímica celular de Phaeodactylum tricomutum (Bohlin, em cultivos estanques Long term changes in the culture medium composition and cellular biochemistry of Phacodactylum tricomutum (Bohlin, in batch cultures

    Directory of Open Access Journals (Sweden)

    Elizabeth Aidar

    1991-01-01

    Full Text Available P. tricornutum was grown in batch cultures under 21ºC temperature and continuous irradiance of 183 µE.m-2 . s-1, provided by fluorescent light tubes. Cultures growth were followed by cell countings, "in vivo" fluorescence and cellular protein, carbohydrate and chlorophyll-α content. The maximum value of protein/carbohydrate ratio was found at the exponential phase and the minimum value at the stationary phase. This ratio characterizes the physiological stage of the culture. Cell uptake rates for nitrate, ammonium and phosphate from the media were higher during the lag-phase. Nitrite excretion by the cells were detected following nitrate uptake.

  4. The rules on suspension cell batch culture of Hedyotis diffusa%白花蛇舌草悬浮细胞分批培养规律的研究

    Institute of Scientific and Technical Information of China (English)

    于瑞莲; 许金国; 顾晓娟

    2012-01-01

    目的 利用白花蛇舌草茎尖的分生组织建立植物悬浮细胞培养系,确定白花蛇舌草悬浮细胞分批培养时的变化规律.方法 通过接种不同量的细胞液确定最适接种量,以细胞干重、蔗糖、铵离子、硝酸盐氮和多糖含量作为检测指标,确定白花蛇舌草悬浮细胞分批培养时的变化规律.结果 白花蛇舌草悬浮细胞分批培养的最适接种量为15%,此时细胞干重达到最大值.在此接种量下,当培养时间达到9d时,pH很快降低到3左右,细胞干重不再增加.培养液中的主要营养成分碳源——蔗糖,在培养开始时,有比较大的降低,在培养后期,细胞干重不再增加时,也不再有大的改变.氮源[N03-]优于[NH4+]先被利用,而且[N0f]的利用速率要远高于[NH4+],达到7.14 μg/(mL·d);细胞液中多糖的生成和细胞的生长属于非偶联型,在培养后期,逐渐大量生成.结论 初步确定白花蛇舌草悬浮细胞分批培养时的变化规律,为以后的培养工艺优化打下了基础.%Purpose Hedyotis diffusa suspension cell was established by the tip of meristem to find out the rules on suspension cell batch culture of Hedyotis diffusa with the time. Methods The optimum inoculum was determined by different inoculation of cell medium. The rules on suspension cell batch culture of Hedyotis diffusa with the time were found by the detection of the amount of cell dry weight, sucrose, ammonium, nitrate and polysaccharide. Results The suspension cell batch culture of Hedyotis diffusa optimum inoculum is 15% .maximum dry cell weight at the same time. At this inoculation,when the incubation time was of 9 days,and pH quickly reduced to about 3 ,the cell dry weight did not increase. The main medium nutrients were carbon -sucrose, a relatively large decreased in the beginning of culture, and the cell dry weight no longer had a big change in the late culture stage. Nitrogen [ NO3-] was used prior to [ NH4+ ] ,and the use

  5. Spring batch essentials

    CERN Document Server

    Rao, P Raja Malleswara

    2015-01-01

    If you are a Java developer with basic knowledge of Spring and some experience in the development of enterprise applications, and want to learn about batch application development in detail, then this book is ideal for you. This book will be perfect as your next step towards building simple yet powerful batch applications on a Java-based platform.

  6. Batch-to-batch uniformity of bacterial community succession and flavor formation in the fermentation of Zhenjiang aromatic vinegar.

    Science.gov (United States)

    Wang, Zong-Min; Lu, Zhen-Ming; Yu, Yong-Jian; Li, Guo-Quan; Shi, Jin-Song; Xu, Zheng-Hong

    2015-09-01

    Solid-state fermentation of traditional Chinese vinegar is a mixed-culture refreshment process that proceeds for many centuries without spoilage. Here, we investigated bacterial community succession and flavor formation in three batches of Zhenjiang aromatic vinegar using pyrosequencing and metabolomics approaches. Temporal patterns of bacterial succession in the Pei (solid-state vinegar culture) showed no significant difference (P > 0.05) among three batches of fermentation. In all the batches investigated, the average number of community operational taxonomic units (OTUs) decreased dramatically from 119 ± 11 on day 1 to 48 ± 16 on day 3, and then maintained in the range of 61 ± 9 from day 5 to the end of fermentation. We confirmed that, within a batch of fermentation process, the patterns of bacterial diversity between the starter (took from the last batch of vinegar culture on day 7) and the Pei on day 7 were similar (90%). The relative abundance dynamics of two dominant members, Lactobacillus and Acetobacter, showed high correlation (coefficient as 0.90 and 0.98 respectively) among different batches. Furthermore, statistical analysis revealed dynamics of 16 main flavor metabolites were stable among different batches. The findings validate the batch-to-batch uniformity of bacterial community succession and flavor formation accounts for the quality of Zhenjiang aromatic vinegar. Based on our understanding, this is the first study helps to explain the rationality of age-old artistry from a scientific perspective. PMID:25998816

  7. Hybrid Batch Bayesian Optimization

    CERN Document Server

    Azimi, Javad; Fern, Xiaoli

    2012-01-01

    Bayesian Optimization aims at optimizing an unknown non-convex/concave function that is costly to evaluate. We are interested in application scenarios where concurrent function evaluations are possible. Under such a setting, BO could choose to either sequentially evaluate the function, one input at a time and wait for the output of the function before making the next selection, or evaluate the function at a batch of multiple inputs at once. These two different settings are commonly referred to as the sequential and batch settings of Bayesian Optimization. In general, the sequential setting leads to better optimization performance as each function evaluation is selected with more information, whereas the batch setting has an advantage in terms of the total experimental time (the number of iterations). In this work, our goal is to combine the strength of both settings. Specifically, we systematically analyze Bayesian optimization using Gaussian process as the posterior estimator and provide a hybrid algorithm t...

  8. Comparison of transcriptional heterogeneity of eight genes between batch Desulfovibrio vulgaris biofilm and planktonic culture at a single-cell level

    Directory of Open Access Journals (Sweden)

    Zhenhua eQi

    2016-04-01

    Full Text Available Sulfate-reducing bacteria (SRB biofilm formed on metal surfaces can change the physicochemical properties of metals and cause metal corrosion. To enhance understanding of differential gene expression in Desulfovibrio vulgaris under planktonic and biofilm growth modes, a single-cell based RT-qPCR approach was applied to determine gene expression levels of 8 selected target genes in four sets of the 31 individual cells isolated from each growth condition (i.e., biofilm formed on a stainless steel (SS) and planktonic cultures, exponential and stationary phases. The results showed obvious gene-expression heterogeneity for the target genes among D. vulgaris single cells of both biofilm and planktonic cultures. In addition, an increased gene-expression heterogeneity in the D. vulgaris biofilm when compared with the planktonic culture was also observed for seven out of eight selected genes, which may be contributing to the increased complexity in terms of structures and morphology in the biofilm. Moreover, the results showed up-regulation of DVU0281 gene encoding exopolysaccharide biosynthesis protein, and down-regulation of genes involved in energy metabolism (i.e., DVU0434 and DVU0588, stress responses (i.e., DVU2410 and response regulator (i.e., DVU3062 in the D. vulgaris biofilm cells. Finally, the gene (DVU2571 involved in iron transportation was found down-regulated, and two genes (DVU1340 and DVU1397 involved in ferric uptake repressor and iron storage were up-regulated in D. vulgaris biofilm, suggesting their possible roles in maintaining normal metabolism of the D. vulgaris biofilm under environments of high concentration of iron. This study showed that the single-cell based analysis could be a useful approach in deciphering metabolism of microbial biofilms.

  9. Improved elastase production by Bacillus sp. EL31410—further optimization and kinetics studies of culture medium for batch fermentation

    Institute of Scientific and Technical Information of China (English)

    何国庆; 陈启和; 琚晓捷; 石乃冬

    2004-01-01

    An efficient culture medium producing a bacterial elastase with high yields was developed further following preliminary studies by means of response surface method. Central composite design (CCD) and response surface methodology were applied to optimize the medium constituents. A central composite design was used to explain the combined effect of three medium constituents, viz, glucose, K2HPO4, MgSO4·7H2O. The strain produced more elastase in the completely optimized medium, as compared with the partially optimized medium. The fitted model of the second model, as per RSM, showed that glucose was 7.4 g/100 ml, casein 1.13 g/100 ml, corn steep flour 0.616 g/100 ml, KEHPO4 0.206 g/100 ml and MgSO4·7H2O 0.034 g/100 ml. The fermentation kinetics of these two culture media in the flask experiments were analyzed. It was found that the highest elastase productivity occurred at 54 hours. Higher glucose concentration had inhibitory effect on elastase production. At the same time, we observed that the glucose consumption rate was slow in the completely optimized medium, which can explain the lag period of the highest elastase production. Some metal ions and surfactant additives also affected elastase production and cell growth.

  10. Study on the Effects of Fed-batch Culture Method of Escherichia coli XD-12 Fermentation%流加培养方式对大肠杆菌XD-12发酵的影响研究

    Institute of Scientific and Technical Information of China (English)

    潘自皓; 顾薇; 潘扬

    2011-01-01

    [Objective] The research aimed to study the fed-batch culture method of Escherichia coli and enhance the fermentation concentration of transaminase donor.E. coli XD-12. [Method] The effects of carbon source feeding, nitrogen source feeding,feeding with pH control on E. coli fermentation were studied to obtain the optimal culture conditions. [ Result] The optimal cultural conditions lot transaminase-produeing E.coli were as Mows; temperature of 37 ℃ .agitation speed of 400 r/min,aeration quantity of 1.5 L/min,initial pH of medium of 7.0,for controlling fermentation process pH of 7.5,initial glucose concentration of 5 g/L,initial nitrogen source of 5 g/L peptone + 1.5 g/L beef extract, 120 g/L glucose solution was intermittently fed at an interval of 2 h after glucose concentration declined to 2 g/L And 15 g/L peptone and 4. 5 g/L beef extract were intermittently fed at an interval of 2 h after 8 hours. After culture 24 h under these conditions, the cell dry weight concentration of E.coli reached 9.66 g/L,104.7% higher than that in batch culture. [ Conclusion] This research was of an important realistic significance for reducing the production cost of preparing L-phenylalanine by enzyme method,enhancing the production efficiency of L-phenylala-nine,sufficing the increasing market requirements of L-phenylalanine.%[目的]研究大肠杆菌流加培养方式,提高转氨醇供体——大肠杆菌XD-12的发酵浓度.[方法]通过研究碳源流加、氮源流加、pH控制流加对发酵的影响,获得了优化的培养条件.[结果]产转氨酶大肠杆菌的最佳培养条件为:温度37℃,搅拌转速500 r/min,通气量1.5 L/min,培养基初始pH为7.0,控制发酵过程pH为7.5,初始葡萄糖浓度5 g/L,初始氮源为5g/L蛋白胨+1.5 g/L牛肉膏,从葡萄糖浓度下降为2 g/L开始每隔2h问歇流加120 g/L的糖,从8h起每隔2h间歇流加15 9/L蛋白胨+4.5 g/L牛肉膏.在此条件下培养24h,大肠杆菌的茵体干重浓度达9.66 g

  11. Dynamic Batch Bayesian Optimization

    CERN Document Server

    Azimi, Javad; Fern, Xiaoli

    2011-01-01

    Bayesian optimization (BO) algorithms try to optimize an unknown function that is expensive to evaluate using minimum number of evaluations/experiments. Most of the proposed algorithms in BO are sequential, where only one experiment is selected at each iteration. This method can be time inefficient when each experiment takes a long time and more than one experiment can be ran concurrently. On the other hand, requesting a fix-sized batch of experiments at each iteration causes performance inefficiency in BO compared to the sequential policies. In this paper, we present an algorithm that asks a batch of experiments at each time step t where the batch size p_t is dynamically determined in each step. Our algorithm is based on the observation that the sequence of experiments selected by the sequential policy can sometimes be almost independent from each other. Our algorithm identifies such scenarios and request those experiments at the same time without degrading the performance. We evaluate our proposed method us...

  12. Modelling of Batch Process Operations

    DEFF Research Database (Denmark)

    Abdul Samad, Noor Asma Fazli; Cameron, Ian; Gani, Rafiqul

    2011-01-01

    Here a batch cooling crystalliser is modelled and simulated as is a batch distillation system. In the batch crystalliser four operational modes of the crystalliser are considered, namely: initial cooling, nucleation, crystal growth and product removal. A model generation procedure is shown that s...

  13. CONVERSION OF PINEAPPLE JUICE WASTE INTO LACTIC ACID IN BATCH AND FED – BATCH FERMENTATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Abdullah Mochamad Busairi

    2012-01-01

    Full Text Available Pineapple juice waste contains valuable components, which are mainly sucrose, glucose, and fructose. Recently, lactic acid has been considered to be an important raw material for the production of biodegradable lactide polymer. The fermentation experiments were carried out in a 3 litres fermentor (Biostat B Model under anaerobic condition with stirring speed of 50 rpm, temperature at 40oC, and pH of 6.00. Effect of feed concentration on lactic acid production, bacterial growth, substrate utilisation and productivity was studied. The results obtained from fed- batch culture fermentation showed that the maximum lactic acid productivity was 0.44 g/L.h for feed concentration of 90 g/L at 48 hours. Whereas the lactic acid productivity obtained from fed-batch culture was twice and half fold higher than that of batch culture productivity.  Buangan jus nanas mengandung komponen yang berharga terutama sukrosa, glukosa, dan fruktosa. Asam laktat adalah bahan baku yang terbaru dan penting untuk dibuat sebagai polimer laktat yang dapat terdegradasi oleh lingkungan. Percobaan dilakukan pada fermentor 3 liter (Model Biostat B di bawah kondisi anaerob dengan kecepatan pengadukan 50 rpm, temperatur 40oC, dan pH 6,00. Pengaruh konsentrasi umpan terhadap produksi asam laktat, pertumbuhan mikroba, pengggunaan substrat dan produktivitas telah dipelajari. Hasil yang didapatkan pada fermentasi dengan menggunakan sistem fed-batch menunjukkan bahwa produktivitas asam laktat maksimum adalah 0.44 g/L,jam dengan konsentrasi umpan, 90 g/L pada waktu 48 jam. Bahkan produktivitas asam laktat yang didapat pada kultur fed-batch lebih tinggi 2,5 kali dari pada proses menggunakan sistem batch

  14. A study on clavulanic acid production by Streptomyces clavuligerus in batch, fed-batch and continuous processes

    Directory of Open Access Journals (Sweden)

    A. B. Neto

    2005-12-01

    Full Text Available Clavulanic acid (CA is a potent inhibitor of beta-lactamases, enzymes that are responsible for the hydrolysis of beta-lactam antibiotics. It is a secondary metabolite produced by the filamentous aerobic bacterium Streptomyces clavuligerus in submerged cultivations. In the present work clavulanic acid production in batch, fed-batch and continuous bioreactors was studied with the objective of increasing productivity. The operating conditions: temperature, aeration and agitation, were the same in all cases, 28º C, 0.5 vvm and 800 rpm, respectively. The CA concentration obtained in the fed-batch culture, 404 mg L-1, was ca twice the value obtained in the batch culture, 194 mg L-1, while 293 mg L-1 was obtained in the continuous culture. The highest productivity was obtained in the continuous cultivation, 10.6 mg L-1 h-1, as compared with 8.8 mg L-1 h-1 in the fed-batch process and 3.5 mg L-1 h-1 in the batch process, suggesting that continuous culture of Streptomyces clavuligerus is a promising strategy for clavulanic acid production.

  15. Column and Batch Experiments

    Directory of Open Access Journals (Sweden)

    Jorge L. Gardea-Torresdey

    2005-01-01

    Full Text Available Batch and column experiments were performed to determine the Cu(II binding capacity of silica-immobilized humin biomass. For column studies, 500 bed volumes of a 0.1 mM Cu(II solution were passed through humin packed columns at the flow rates of 1, 1.5, 2, and 3 mL/min. The biopolymer showed an average Cu binding capacity of 12 ± 1.5 mg/g and a Cu recovery of about 96.5 % ± 1.5. The breakthrough points for Cu(II alone were approximately 420, 390, 385, and 300 bed volumes for the flow rates of 1, 1.5, 2 and 3 mL/min, respectively. The interference studies demonstrated that at low concentrations, the hard cations Ca(II and Mg(II did not seem to represent a major interference on Cu(II binding to the humin biopolymer. The selectivity showed by this biopolymer was Cu(II>Ca(II>Mg(II. On the other hand, batch experiments showed that Ca(II + Mg(II at 100mM each reduced the Cu(II binding to 73 %. However, 1000 mM concentrations of Ca(II and Mg(II, separately and in mixture, reduced the Cu(II binding to 47 %, 44 % and 31 %, respectively. The results of this study showed that immobilized humin in a silica matrix could represent an inexpensive bio-source for Cu removal from contaminated water, even in the presence of low concentrations of the hard cations Ca(II and Mg(II.

  16. Data-driven batch schuduling

    Energy Technology Data Exchange (ETDEWEB)

    Bent, John [Los Alamos National Laboratory; Denehy, Tim [GOOGLE; Arpaci - Dusseau, Remzi [UNIV OF WISCONSIN; Livny, Miron [UNIV OF WISCONSIN; Arpaci - Dusseau, Andrea C [NON LANL

    2009-01-01

    In this paper, we develop data-driven strategies for batch computing schedulers. Current CPU-centric batch schedulers ignore the data needs within workloads and execute them by linking them transparently and directly to their needed data. When scheduled on remote computational resources, this elegant solution of direct data access can incur an order of magnitude performance penalty for data-intensive workloads. Adding data-awareness to batch schedulers allows a careful coordination of data and CPU allocation thereby reducing the cost of remote execution. We offer here new techniques by which batch schedulers can become data-driven. Such systems can use our analytical predictive models to select one of the four data-driven scheduling policies that we have created. Through simulation, we demonstrate the accuracy of our predictive models and show how they can reduce time to completion for some workloads by as much as 80%.

  17. BatchJobs and BatchExperiments: Abstraction Mechanisms for Using R in Batch Environments

    Directory of Open Access Journals (Sweden)

    Bernd Bischl

    2015-03-01

    Full Text Available Empirical analysis of statistical algorithms often demands time-consuming experiments. We present two R packages which greatly simplify working in batch computing environments. The package BatchJobs implements the basic objects and procedures to control any batch cluster from within R. It is structured around cluster versions of the well-known higher order functions Map, Reduce and Filter from functional programming. Computations are performed asynchronously and all job states are persistently stored in a database, which can be queried at any point in time. The second package, BatchExperiments, is tailored for the still very general scenario of analyzing arbitrary algorithms on problem instances. It extends package BatchJobs by letting the user define an array of jobs of the kind apply algorithm A to problem instance P and store results. It is possible to associate statistical designs with parameters of problems and algorithms and therefore to systematically study their influence on the results. The packages main features are: (a Convenient usage: All relevant batch system operations are either handled internally or mapped to simple R functions. (b Portability: Both packages use a clear and well-defined interface to the batch system which makes them applicable in most high-performance computing environments. (c Reproducibility: Every computational part has an associated seed to ensure reproducibility even when the underlying batch system changes. (d Abstraction and good software design: The code layers for algorithms, experiment definitions and execution are cleanly separated and enable the writing of readable and maintainable code.

  18. BatchJS: Implementing Batches in JavaScript

    NARCIS (Netherlands)

    Kasemier, D.

    2014-01-01

    None of our popular programming languages know how to handle distribution well. Yet our programs interact more and more with each other and our data resorts in databases and web services. Batches are a new addition to languages that can finally bring native support for distribution to our favourite

  19. Physicochemical Characteristics of Transferon™ Batches

    Directory of Open Access Journals (Sweden)

    Emilio Medina-Rivero

    2016-01-01

    Full Text Available Transferon, a biotherapeutic agent that has been used for the past 2 decades for diseases with an inflammatory component, has been approved by regulatory authorities in Mexico (COFEPRIS for the treatment of patients with herpes infection. The active pharmaceutical ingredient (API of Transferon is based on polydispersion of peptides that have been extracted from lysed human leukocytes by a dialysis process and a subsequent ultrafiltration step to select molecules below 10 kDa. To physicochemically characterize the drug product, we developed chromatographic methods and an SDS-PAGE approach to analyze the composition and the overall variability of Transferon. Reversed-phase chromatographic profiles of peptide populations demonstrated batch-to-batch consistency from 10 representative batches that harbored 4 primary peaks with a relative standard deviation (RSD of less than 7%. Aminogram profiles exhibited 17 proteinogenic amino acids and showed that glycine was the most abundant amino acid, with a relative content of approximately 18%. Further, based on their electrophoretic migration, the peptide populations exhibited a molecular mass of about 10 kDa. Finally, we determined the Transferon fingerprint using a mass spectrometry tool. Because each batch was produced from independent pooled buffy coat samples from healthy donors, supplied by a local blood bank, our results support the consistency of the production of Transferon and reveal its peptide identity with regard to its physicochemical attributes.

  20. Physicochemical Characteristics of Transferon™ Batches

    Science.gov (United States)

    Pérez-Sánchez, Gilberto; Favari, Liliana; Estrada-Parra, Sergio

    2016-01-01

    Transferon, a biotherapeutic agent that has been used for the past 2 decades for diseases with an inflammatory component, has been approved by regulatory authorities in Mexico (COFEPRIS) for the treatment of patients with herpes infection. The active pharmaceutical ingredient (API) of Transferon is based on polydispersion of peptides that have been extracted from lysed human leukocytes by a dialysis process and a subsequent ultrafiltration step to select molecules below 10 kDa. To physicochemically characterize the drug product, we developed chromatographic methods and an SDS-PAGE approach to analyze the composition and the overall variability of Transferon. Reversed-phase chromatographic profiles of peptide populations demonstrated batch-to-batch consistency from 10 representative batches that harbored 4 primary peaks with a relative standard deviation (RSD) of less than 7%. Aminogram profiles exhibited 17 proteinogenic amino acids and showed that glycine was the most abundant amino acid, with a relative content of approximately 18%. Further, based on their electrophoretic migration, the peptide populations exhibited a molecular mass of about 10 kDa. Finally, we determined the Transferon fingerprint using a mass spectrometry tool. Because each batch was produced from independent pooled buffy coat samples from healthy donors, supplied by a local blood bank, our results support the consistency of the production of Transferon and reveal its peptide identity with regard to its physicochemical attributes. PMID:27525277

  1. NDA BATCH 2002-02

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence Livermore National Laboratory

    2009-12-09

    QC sample results (daily background checks, 20-gram and 100-gram SGS drum checks) were within acceptable criteria established by WIPP's Quality Assurance Objectives for TRU Waste Characterization. Replicate runs were performed on 5 drums with IDs LL85101099TRU, LL85801147TRU, LL85801109TRU, LL85300999TRU and LL85500979TRU. All replicate measurement results are identical at the 95% confidence level as established by WIPP criteria. Note that the batch covered 5 weeks of SGS measurements from 23-Jan-2002 through 22-Feb-2002. Data packet for SGS Batch 2002-02 generated using gamma spectroscopy with the Pu Facility SGS unit is technically reasonable. All QC samples are in compliance with established control limits. The batch data packet has been reviewed for correctness, completeness, consistency and compliance with WIPP's Quality Assurance Objectives and determined to be acceptable. An Expert Review was performed on the data packet between 28-Feb-02 and 09-Jul-02 to check for potential U-235, Np-237 and Am-241 interferences and address drum cases where specific scan segments showed Se gamma ray transmissions for the 136-keV gamma to be below 0.1 %. Two drums in the batch showed Pu-238 at a relative mass ratio more than 2% of all the Pu isotopes.

  2. Simulated Batch Production of Penicillin

    Science.gov (United States)

    Whitaker, A.; Walker, J. D.

    1973-01-01

    Describes a program in applied biology in which the simulation of the production of penicillin in a batch fermentor is used as a teaching technique to give students experience before handling a genuine industrial fermentation process. Details are given for the calculation of minimum production cost. (JR)

  3. Batching System for Superior Service

    Science.gov (United States)

    2001-01-01

    Veridian's Portable Batch System (PBS) was the recipient of the 1997 NASA Space Act Award for outstanding software. A batch system is a set of processes for managing queues and jobs. Without a batch system, it is difficult to manage the workload of a computer system. By bundling the enterprise's computing resources, the PBS technology offers users a single coherent interface, resulting in efficient management of the batch services. Users choose which information to package into "containers" for system-wide use. PBS also provides detailed system usage data, a procedure not easily executed without this software. PBS operates on networked, multi-platform UNIX environments. Veridian's new version, PBS Pro,TM has additional features and enhancements, including support for additional operating systems. Veridian distributes the original version of PBS as Open Source software via the PBS website. Customers can register and download the software at no cost. PBS Pro is also available via the web and offers additional features such as increased stability, reliability, and fault tolerance.A company using PBS can expect a significant increase in the effective management of its computing resources. Tangible benefits include increased utilization of costly resources and enhanced understanding of computational requirements and user needs.

  4. Repeated-batch production of kojic acid in a cell-retention fermenter using Aspergillus oryzae M3B9.

    Science.gov (United States)

    Wan, H M; Chen, C C; Giridhar, R; Chang, T S; Wu, W T

    2005-06-01

    A cell-retention fermenter was used for the pilot-scale production of kojic acid using an improved strain of Aspergillus oryzae in repeated-batch fermentations. Among the various carbon and nitrogen sources used, sucrose and yeast extract promoted pellet morphology of fungi and higher kojic acid production. Repeated-batch culture using a medium replacement ratio of 75% gave a productivity of 5.3 gL(-1)day(-1) after 11.5 days of cultivation. While batch culture in shake-flasks resulted in a productivity of 5.1 gL(-1)day(-1), a productivity of 5 gL(-1)day(-1) was obtained in a pilot-scale fermenter. By converting the batch culture into repeated batches, the non-productive downtime of cleaning, filling and sterilizing the fermenter between each batch were eliminated, thereby increasing the kojic acid productivity. PMID:15895266

  5. Batch-related sterile endophthalmitis following intravitreal injection of bevacizumab

    Directory of Open Access Journals (Sweden)

    Morteza Entezari

    2014-01-01

    Full Text Available Background: To report a series of patients with sterile endophthalmitis after intravitreal bevacizumab (IVB injection from 2 different batches of bevacizumab. Materials and Methods: Records of 11 eyes with severe inflammation after IVB injections from two different batches (7 eyes from one and 4 from the other on two separate days were evaluated. Fifteen eyes of 15 patients in one day were treated with one batch and 18 eyes of 17 patients were treated another day using another batch injected for different retinal diseases. Each batch was opened on the day of injection. We used commercially available bevacizumab (100 mg/4 ml kept at 4°C. Severe cases with hypopyon were admitted to the ward and underwent anterior chamber and vitreous tap for direct smear and culture. Results: Pain, redness and decreased vision began after 11-17 days. All had anterior chamber and vitreous reactions and 5 had hypopyon. Antibiotics and corticosteroids were initiated immediately, but the antibiotics were discontinued after negative culture results. Visual acuity returned to pre-injection levels in 10 eyes after 1 month and only in one eye pars plana vitrectomy was performed. Mean VA at the time of presentation with inflammation (1.76 ± 0.78 logMAR decreased significantly (P = 0.008 compared to the initial mean corrected VA (1.18 ± 0.55 logMAR; however, final mean corrected VA (1.02 ± 0.48 logMAR improved in comparison with the baseline but not to a significant level (P = 0.159. Conclusions: We report a cluster of sterile endophthalmitis following intravitreal injection of bevacizumab from the same batch of bevacizumab that has a favorable prognosis.

  6. NDA Batch 2002-13

    Energy Technology Data Exchange (ETDEWEB)

    Hollister, R

    2009-09-17

    QC sample results (daily background check drum and 100-gram SGS check drum) were within acceptance criteria established by WIPP's Quality Assurance Objectives for TRU Waste Characterization. Replicate runs were performed on drum LL85501243TRU. Replicate measurement results are identical at the 95% confidence level as established by WIPP criteria. HWM NCAR No. 02-1000168 issued on 17-Oct-2002 regarding a partially dislodged Cd sheet filter on the HPGe coaxial detector. This physical geometry occurred on 01-Oct-2002 and was not corrected until 10-Oct-2002, during which period is inclusive of the present batch run of drums. Per discussions among the Independent Technical Reviewer, Expert Reviewer and the Technical QA Supervisor, as well as in consultation with John Fleissner, Technical Point of Contact from Canberra, the analytical results are technically reliable. All QC standard runs during this period were in control. Data packet for SGS Batch 2002-13 generated using passive gamma-ray spectroscopy with the Pu Facility SGS unit is technically reasonable. All QC samples are in compliance with establiShed control limits. The batch data packet has been reviewed for correctness, completeness, consistency and compliance with WIPP's Quality Assurance Objectives and determined to be acceptable.

  7. Batch-oriented software appliances

    CERN Document Server

    Murri, Riccardo

    2012-01-01

    This paper presents AppPot, a system for creating Linux software appliances. AppPot can be run as a regular batch or grid job and executed in user space, and requires no special virtualization support in the infrastructure. The main design goal of AppPot is to bring the benefits of a virtualization-based IaaS cloud to existing batch-oriented computing infrastructures. In particular, AppPot addresses the application deployment and configuration on large heterogeneous computing infrastructures: users are enabled to prepare their own customized virtual appliance for providing a safe execution environment for their applications. These appliances can then be executed on virtually any computing infrastructure being in a private or public cloud as well as any batch-controlled computing clusters the user may have access to. We give an overview of AppPot and its features, the technology that makes it possible, and report on experiences running it in production use within the Swiss National Grid infrastructure SMSCG.

  8. 间歇结晶过程的分批优化%Batch-to-batch Optimization of Batch Crystallization Processes

    Institute of Scientific and Technical Information of China (English)

    Woranee Paengjuntuek; Paisan Kittisupakorn; Amornchai Arpornwichanop

    2008-01-01

    It is the fact that several process parameters are either unknown or uncertain. Therefore, an optimal control profile calculated with developed process models with respect to such process parameters may not give an optimal performance when implemented to real processes. This study proposes a batch-to-batch optimization strat-egy for the estimation of uncertain kinetic parameters in a batch crystallization process of potassium sulfate produc-tion. The knowledge of a crystal size distribution of the product at the end of batch operation is used in the proposedmethodology. The updated kinetic parameters are applied for determining an optimal operating temperature policy for the next batch run.

  9. Fed-batch Fermentation of Lactic Acid Bacteria to Improve Biomass Production: A Theoretical Approach

    Science.gov (United States)

    Beng Lee, Boon; Tham, Heng Jin; Chan, Eng Seng

    Recently, fed-batch fermentation has been introduced in an increasing number of fermentation processes. Previous researches showed that fed-batch fermentation can increase the biomass yield of many strains. Improvement of the biomass yield is interested because biomass from lactic acid bacteria (LAB) fermentation is widely used in food and pharmaceutical industry. The aim of this research is to study the ability and feasibility of fed-batch fermentation to improve biomass production of LAB. Appropriate model has been selected from literature. Monod equation described the substrate limitation of LAB and the product inhibition of LAB follows a non-competitive model. Furthermore, the lactic acid production follows Luedeking and Piret model. Then the models are applied to simulate the fermentation of batch and fed-batch cultures by using MATLAB. From the results of simulation, fed-batch fermentation showed that substrate limitation and substrate inhibition can be avoided. Besides that, the variable volume fed-batch fermentation also showed that product inhibition can be eliminated by diluting the product concentration with added fresh feed. However, it was found that fed-batch fermentation is not economically feasible because large amount of substrate is required to reduce the product inhibition effect. Therefore, fed-batch fermentation plays more importance role if the fermentation strain has high Ks value or low Kp value.

  10. Combinatorial Batch Codes with Redundancy

    OpenAIRE

    Jung, Jiyoon; Mummert, Carl; Niese, Elizabeth; Schroeder, Michael w.

    2015-01-01

    A combinatorial batch code with redundancy $r$ and parameters $(n,k,m,t)$ can be represented as a system $C$ of $m$ (not necessarily distinct) subsets of an underlying $n$-element set $F$, so that each $k$-subset of $F$ can be covered by every $(m-r)$-subset $K$ of $C$ while taking no more than $t$ elements of $F$ with each set in $K$. The sum of the cardinalities of the sets in $C$ is the weight of the code. We focus on the case $t =1$, and determine the minimal weight for several ranges of ...

  11. Differences in stationary-phase cells of a commercial Saccharomyces cerevisiae wine yeast grown in aerobic and microaerophilic batch cultures assessed by electric particle analysis, light diffraction and flow cytometry.

    Science.gov (United States)

    Portell, X; Ginovart, M; Carbó, R; Vives-Rego, J

    2011-01-01

    We applied electric particle analysis, light diffraction and flow cytometry to obtain information on the morphological changes during the stationary phase of Saccharomyces cerevisiae. The reported analyses of S. cerevisiae populations were obtained under two different conditions, aerobic and microaerophilic, at 27°C. The samples analysed were taken at between 20 and 50 h from the beginning of culture. To assist in the interpretation of the observed distributions a complexity index was used. The aerobically grown culture reached significantly greater cell density. Under these conditions, the cell density experienced a much lower reduction (3%) compared with the microaerophilic conditions (30%). Under aerobic conditions, the mean cell size determined by both electric particle analysis and light diffraction was lower and remained similar throughout the experiment. Under microaerophilic conditions, the mean cell size determined by electric particle analysis decreased slightly as the culture progressed through the stationary phase. Forward and side scatter distributions revealed two cell subpopulations under both growth conditions. However, in the aerobic growing culture the two subpopulations were more separated and hence easier to distinguish. The distributions obtained with the three experimental techniques were analysed using the complexity index. This analysis suggested that a complexity index is a good descriptor of the changes that take place in a yeast population in the stationary phase, and that it aids in the discussion and understanding of the implications of these distributions obtained by these experimental techniques.

  12. cultural

    Directory of Open Access Journals (Sweden)

    Irene Kreutz

    2006-01-01

    Full Text Available Es un estudio cualitativo que adoptó como referencial teorico-motodológico la antropología y la etnografía. Presenta las experiencias vivenciadas por mujeres de una comunidad en el proceso salud-enfermedad, con el objetivo de comprender los determinantes sócio-culturales e históricos de las prácticas de prevención y tratamiento adoptados por el grupo cultural por medio de la entrevista semi-estructurada. Los temas que emergieron fueron: la relación entre la alimentación y lo proceso salud-enfermedad, las relaciones con el sistema de salud oficial y el proceso salud-enfermedad y lo sobrenatural. Los dados revelaron que los moradores de la comunidad investigada tienen un modo particular de explicar sus procedimientos terapéuticos. Consideramos que es papel de los profesionales de la salud en sus prácticas, la adopción de abordajes o enfoques que consideren al individuo en su dimensión sócio-cultural e histórica, considerando la enorme diversidad cultural en nuestro país.

  13. Role of transcription and enzyme activities in redistribution of carbon and electron flux in response to N₂ and H₂ sparging of open-batch cultures of Clostridium thermocellum ATCC 27405.

    Science.gov (United States)

    Carere, Carlo R; Rydzak, Thomas; Cicek, Nazim; Levin, David B; Sparling, Richard

    2014-03-01

    Growth, end-product synthesis, enzyme activities, and transcription of select genes associated with the "malate shunt," pyruvate catabolism, H2 synthesis, and ethanol production were studied in the cellulolytic anaerobe, Clostridium thermocellum ATCC 27405, during open-batch fermentation of cellobiose to determine the effect of elevated N2 and H2 gas sparging on metabolism using a 14-L fermenter with a 7-L working volume. The metabolic shift from acetate, H2, and CO2 to ethanol and formate in response to high H2 versus high N2 sparging (20 mL s(-1)) was accompanied by (a) a 2-fold increase in nicotinamide adenine dinucleotide (NADH)-dependent alcohol dehydrogenase (Adh) activity, (b) a 10-fold increase in adhE transcription, and (c) a 3-fold decrease in adhZ transcription. A similar, but less pronounced, metabolic shift was also observed when the rate of N2 sparging was decreased from 20 to 2 mL s(-1), during which (a) NADH-dependent ADH and pyruvate: ferredoxin oxidoreductase (PFOR) activities increased by ∼1.5-fold, (b) adhY transcription increased 6-fold, and (c) transcription of selected pfor genes increased 2-fold. Here we demonstrate that transcription of genes involved in ethanol metabolism is tightly regulated in response to gas sparging. We discuss the potential impacts of dissolved H2 on electron carrier (NADH, NADPH, ferredoxin) oxidation and how these electron carriers can redirect carbon and electron flux and regulate adhE transcription. PMID:24463715

  14. Batch process design: an overview from control

    OpenAIRE

    Zuluaga Bedoya, Christian Camilo

    2015-01-01

    Abstract: batch process design: an overview from control In this work, the topic of batch process design is addressed, through an analysis of the phenomenological-based model and using set-theoretic methods to deduce process constraints and parametric effects in state controllability. A review of literature is presented about characterization of batch process from point of view of design problem. Furthermore simultaneous process and control design is also reviewed, considering the main contri...

  15. Production of Human Epidermal Growth Factor in Fed-batch Culture of Acetate-tolerant Escherichia coli%补料分批培养耐乙酸大肠杆菌生产人表皮生长因子

    Institute of Scientific and Technical Information of China (English)

    韩云; 李志敏; 杜鹏; 甘人宝; 叶勤

    2007-01-01

    An acetate-tolerant mutant of Escherichia coli DH5α, DA19, was used for secretory production of human epidermal growth factor (hEGF) whose expression was under the control of phoA promoter. The recombinant cells were cultured in a chemically defined medium, and glucose was added at different specific provision rates during the growth and expression phases. It was found that pH had a significant effect on the extracellular hEGF production. The extracellular hEGF concentration was 75.5mg·L-1, 5.2-fold of the level reached at pH 7.0, even though more acetate was produced. Nitrogen source was limited in the later growth phase. Supplementation of ammonium promoted the consumption of phosphate and reduced the time to exhaust phosphate, but the extracellular hEGF production was similar to that without supplementation of ammonium.

  16. Operation of a Batch Stripping Distillation Column

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A stripping batch distillation column is preferred when the amount of the light component in the feed is small and the products are to be recovered at high purity. The operation modes of a batch stripping are believed to be the same as those of a rectifier. However, the control system of a stripper is different. In this paper, we explore three different control methods with Hysys (Hyprotech Ltd. 1997) for a batch stripper. The main difference is the control scheme for reboiler liquid level: (a) controlled by reflux flow; (b) controlled by reboiler heat duty; (c) controlled by bottom product flow. The main characteristics of operating a batch stripper with different control scheme are presented in this paper. Guidelines are provided for the startup of a batch stripper, the effects of somecontrol tuning parameters on the column performance are discussed.

  17. Batch process. Changes and problems of a batch process; Bacchi prosesu no hensen to kadai

    Energy Technology Data Exchange (ETDEWEB)

    Niwa, T. [Asahi Engineering (Japan)

    1997-09-05

    One of the characteristics of the manufacture of fine chemical products is multikind production. The life cycles of chemical industrial products have become shorter, and the difference between these life cycles and those of the manufacturing facility has become larger. The use of an FMS (Flexible Manufacturing System) has been demanded as the measure for solving the problems, and the advantages of a batch process have begun to be reconsidered. This paper describes the history of the development of a batch process, and then explains the problems of a batch process. The paper mentions the process control techniques, production information control systems, production support systems, training systems and process simulation systems as the main techniques supporting the development of a batch process. The paper mentions the modeling and standardizing of a batch process, systematic batch process designing methods and the modeling of a production control information system as the problems of a batch process. 8 refs., 5 figs., 2 tabs.

  18. Simulation of kefiran production of Lactobacillus kefiranofaciens JCM6985 in fed-batch reactor

    Directory of Open Access Journals (Sweden)

    Benjamas Cheirsilp

    2006-09-01

    Full Text Available Kinetics of kefiran production by Lactobacillus kefiranofaciens JCM6985 has been investigated. A mathematical model taking into account the mechanism of exopolysaccharides production has been developed. Experiments were carried out in batch mode in order to obtain kinetic model parameters that were further applied to simulate fed-batch processes. A simplification of parameter fitting was also introduced for complicated model. The fed-batch mode allows more flexibility in the control of the substrate concentration as well as product concentration in the culture medium. Based on the batch mathematical model, a fed-batch model was developed and simulations were done. Simulation study in fed-batch reactor resulted that substrate concentration should be controlled at 20 g L-1 to soften the product inhibition and also to stimulate utilization of substrate and its hydrolysate. From simulation results of different feeding techniques, it was found that constant feeding at 0.01 L h-1 was most practically effective feeding profile for exopolysaccharides production in fed-batch mode.

  19. Growth kinetics of Saccharomyces cerevisiae in batch and fed-batch cultivation using sugarcane molasses and glucose syrup from cassava starch.

    Science.gov (United States)

    Win, S S; Impoolsup, A; Noomhorm, A

    1996-02-01

    Growth kinetics of Saccharomyces cerevisiae in glucose syrup from cassava starch and sugarcane molasses were studied using batch and fed-batch cultivation. The optimum temperature and pH required for growth were 30 degrees C and pH 5.5, respectively. In batch culture the productivity and overall cell yield were 0.31 g L-1 h-1 and 0.23 g cells g-1 sugar, respectively, on glucose syrup and 0.22 g L-1 h-1 and 0.18 g cells g-1 sugar, respectively, on molasses. In fed-batch cultivation, a productivity of 3.12 g L-1 h-1 and an overall cell yield of 0.52 g cells g-1 sugar were achieved in glucose syrup cultivation and a productivity of 2.33 g L-1 h-1 and an overall cell yield of 0.46 g cells g-1 sugar were achieved in molasses cultivation by controlling the reducing sugar concentration at its optimum level obtained from the fermentation model. By using an on-line ethanol sensor combined with a porous Teflon tubing method in automating the feeding of substrate in the fed-batch culture, a productivity of 2.15 g L-1 h-1 with a yield of 0.47 g cells g-1 sugar was achieved using glucose syrup as substrate when ethanol concentration was kept at a constant level by automatic control.

  20. LSF usage for batch at CERN

    CERN Multimedia

    Schwickerath, Ulrich

    2007-01-01

    Contributed poster to the CHEP07. Original abstract: LSF 7, the latest version of Platform's batch workload management system, addresses many issues which limited the ability of LSF 6.1 to support large scale batch farms, such as the lxbatch service at CERN. In this paper we will present the status of the evaluation and deployment of LSF 7 at CERN, including issues concerning the integration of LSF 7 with the gLite grid middleware suite and, in particular, the steps taken to endure an efficient reporting of the local batch system status and usage to the Grid Information System

  1. A high-yielding, generic fed-batch process for recombinant antibody production of GS-engineered cell lines

    DEFF Research Database (Denmark)

    Fan, Li; Zhao, Liang; Sun, Yating;

    2009-01-01

    (lactate and osmolality). The proportionalities of nutritional consumption were determined by direct analysis. And the robust, metabolically responsive feeding strategy was based on the off-line measurement of glucose. The fed-batch process was shown to perform equivalently in GS-CHO and GS-NS0 culture....... Compared to batch cultures, the fed-batch technology generated the magnitude of the increase in cell yields (5 fold) and final antibody concentrations (4-8 fold). The majority of the increase in final antibody concentration was functions of the increased cell density and the prolonged culture time....... This generic and high-yielding fed-batch process would shorten development time, and ensure process stability, thereby facilitating the manufacture of therapeutic antibodies by GS-engineered cell lines....

  2. Batch process. Application of CAE technique to a batch process; Bacchi purosesu eno CAE gijutsu no tenkai

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.; Nakai, K.; Oba, S. [Aspentic Japan Co. Ltd. (Japan)

    1997-09-05

    This paper introduces recent topics of the application of the CAE technique to a batch process. A batch distillation modeling tool (BATCHFRAC) is aimed at modeling a distillation tower and a batch reactor for a batch process for fine chemical products, and is provided as an expanded additional function for ASPEN FLUS batch distillation. A batch process designing system (BATCH PLUS) is a comprehensive batch process simulator for efficiently carrying out the designing, the development or the analysis of a complicated recipe-based batch process concerning medical treatment, biotechnology and agriculture. A batch process information control system (Batch/21) is provided as a system having an expanded and additional function for a batch process of InfoPlus/21, an information control system which enables the observation, management and controlling of a process. 4 figs.

  3. Multi-objective optimization of glycopeptide antibiotic production in batch and fed batch processes

    DEFF Research Database (Denmark)

    Maiti, Soumen K.; Eliasson Lantz, Anna; Bhushan, Mani;

    2011-01-01

    as pareto optimal solutions. These solutions gives flexibility in evaluating the trade-offs and selecting the most suitable operating policy. Here, ε-constraint approach was used to generate the pareto solutions for two objectives: product concentration and product per unit cost of media, for batch and fed...... batch operations using process model for Amycolatopsis balhimycina, a glycopeptide antibiotic producer. This resulted in a set of several pareto optimal solutions with the two objectives ranging from (0.75gl−1, 3.97g$-1) to (0.44gl−1, 5.19g$-1) for batch and from (1.5gl−1, 5.46g$-1) to (1.1gl−1, 6.34g......$-1) for fed batch operations. One pareto solution each for batch and for fed batch mode was experimentally validated....

  4. Production and partial characterization of alkaline feruloyl esterases by Fusarium oxysporum during submerged batch cultivation

    DEFF Research Database (Denmark)

    Topakas, E.; Christakopoulos, Paul

    2004-01-01

    Production of feruloyl esterases (FAEs) by Fusarium oxysporum was enhanced by optimization of initial pH of the culture medium, the type and concentration of nitrogen and carbon source. Submerged batch cultivation in a laboratory bioreactor (17 1) produced activity at 82 nkat g(-1) dry substrate...

  5. Kinetics of D-lactic acid production by Sporolactobacillus sp. strain CASD using repeated batch fermentation.

    Science.gov (United States)

    Zhao, Bo; Wang, Limin; Li, Fengsong; Hua, Dongliang; Ma, Cuiqing; Ma, Yanhe; Xu, Ping

    2010-08-01

    D-lactic acid was produced by Sporolactobacillus sp. strain CASD in repeated batch fermentation with one- and two-reactor systems. The strain showed relatively high energy consumption in its growth-related metabolism in comparison with other lactic acid producers. When the fermentation was repeated with 10% (v/v) of previous culture to start a new batch, D-lactic acid production shifted from being cell-maintenance-dependent to cell-growth-dependent. In comparison with the one-reactor system, D-lactic acid production increased approximately 9% in the fourth batch of the two-reactor system. Strain CASD is an efficient D-lactic acid producer with increased growth rate at the early stage of repeated cycles, which explains the strain's physiological adaptation to repeated batch culture and improved performance in the two-reactor fermentation system. From a kinetic point of view, two-reactor fermentation system was shown to be an alternative for conventional one-reactor repeated batch operation. PMID:20374976

  6. Applying prior knowledge to model batch keeping-quality of cucumber batches

    NARCIS (Netherlands)

    Schouten, R.E.; Tijskens, L.M.M.; Kooten, van O.; Jongbloed, G.

    2004-01-01

    Keeping-quality of individual cucumbers is limited by the green colour; the keeping-quality of batches of cucumbers is limited by the time it takes before 5␘f the cucumbers in the batch reach a predefined colour limit. From literature concerning the synthesis and degradation of chlorophyll and a pub

  7. Quality and Batch-to-Batch Consistency of Original and Biosimilar Epoetin Products.

    Science.gov (United States)

    Halim, Liem Andhyk; Brinks, Vera; Jiskoot, Wim; Romeijn, Stefan; Haselberg, Rob; Burns, Chris; Wadhwa, Meenu; Schellekens, Huub

    2016-02-01

    Comprehensive physicochemical characterization and biological assays are essential parts in assessing quality attributes of biologicals. Here, we compared the quality of different marketed recombinant human erythropoietin (epoetin) products: originators, Eprex and NeoRecormon as well as 2 biosimilars, Retacrit and Binocrit. In addition, assessment of batch-to-batch variability was included by collecting 2 or more batches of each product. Common assays which included sodium dodecyl sulfate-polyacrylamide gel electrophoresis, high-performance size-exclusion chromatography, asymmetrical flow field-flow fractionation, capillary zone electrophoresis, and potency testing were used. Of the tested products and among batches of single products, variations in epoetin content, isoform profiles, and potency were found. Ultimately, this study demonstrated the high quality of epoetin products with some degree of variation among products and batches, confirming the "similar but not identical" paradigm of biologicals. PMID:26869417

  8. Dynamic Fractional Resource Scheduling vs. Batch Scheduling

    CERN Document Server

    Casanova, Henri; Vivien, Frédéric

    2011-01-01

    We propose a novel job scheduling approach for homogeneous cluster computing platforms. Its key feature is the use of virtual machine technology to share fractional node resources in a precise and controlled manner. Other VM-based scheduling approaches have focused primarily on technical issues or on extensions to existing batch scheduling systems, while we take a more aggressive approach and seek to find heuristics that maximize an objective metric correlated with job performance. We derive absolute performance bounds and develop algorithms for the online, non-clairvoyant version of our scheduling problem. We further evaluate these algorithms in simulation against both synthetic and real-world HPC workloads and compare our algorithms to standard batch scheduling approaches. We find that our approach improves over batch scheduling by orders of magnitude in terms of job stretch, while leading to comparable or better resource utilization. Our results demonstrate that virtualization technology coupled with light...

  9. Exploring the Transition From Batch to Online

    DEFF Research Database (Denmark)

    Jørgensen, Anker Helms

    2010-01-01

    The transition from using computers in batch mode with punch cards, paper tape, piles of print, and lengthy response times to online mode by way of the video display terminal took place in most organizations in the 1970s and 1980s. The video display terminal was a significant forerunner of the tr......The transition from using computers in batch mode with punch cards, paper tape, piles of print, and lengthy response times to online mode by way of the video display terminal took place in most organizations in the 1970s and 1980s. The video display terminal was a significant forerunner...... structures, and acquire new skills. This work-in-progress paper extends an earlier study of the transition from batch to online, based on oral history interviews with (ex)-employees in two large Danish Service Bureaus. The paper takes the next step by ana-lyzing a particular genre: the commercial computer...

  10. Differential responses of gut microbiota to the same prebiotic formula in oligotrophic and eutrophic batch fermentation systems

    OpenAIRE

    Wenmin Long; Zhengsheng Xue; Qianpeng Zhang; Zhou Feng; Laura Bridgewater; Linghua Wang; Liping Zhao; Xiaoyan Pang

    2015-01-01

    The same prebiotics have produced inconsistent effects on microbiota when evaluated in different batch fermentation studies. To understand the reasons behind these discrepancies, we compared impact of one prebiotic formula on the same inoculated fecal microbiota in two frequently used batch systems: phosphate-buffered saline (PBS, oligotrophic) and basal culture medium (BCM, eutrophic). The microbiota was monitored using 454 pyrosequencing. Negative controls (no prebiotic) of both systems sho...

  11. Perfusion based cell culture chips

    DEFF Research Database (Denmark)

    Heiskanen, Arto; Emnéus, Jenny; Dufva, Martin

    2010-01-01

    Performing cell culture in miniaturized perfusion chambers gives possibilities to experiment with cells under near in vivo like conditions. In contrast to traditional batch cultures, miniaturized perfusion systems provide precise control of medium composition, long term unattended cultures...... and tissue like structuring of the cultures. However, as this chapter illustrates, many issues remain to be identified regarding perfusion cell culture such as design, material choice and how to use these systems before they will be widespread amongst biomedical researchers....

  12. Following an Optimal Batch Bioreactor Operations Model

    DEFF Research Database (Denmark)

    Ibarra-Junquera, V.; Jørgensen, Sten Bay; Virgen-Ortíz, J.J.;

    2012-01-01

    The problem of following an optimal batch operation model for a bioreactor in the presence of uncertainties is studied. The optimal batch bioreactor operation model (OBBOM) refers to the bioreactor trajectory for nominal cultivation to be optimal. A multiple-variable dynamic optimization of fed...... as the master system which includes the optimal cultivation trajectory for the feed flow rate and the substrate concentration. The “real” bioreactor, the one with unknown dynamics and perturbations, is considered as the slave system. Finally, the controller is designed such that the real bioreactor...

  13. Development of Fed-Batch Cultivation Strategy for Efficient Oxytetracycline Production by Streptomyces rimosus at Semi-Industrial Scale

    Directory of Open Access Journals (Sweden)

    Elsayed Ahmed Elsayed

    2015-10-01

    Full Text Available ABSTRACTOxytetracycline (OTC production byStreptomyces rimosus was studied in batch and fed-batch cultures in shake flask and bioreactor levels using semi-defined medium. First, the effect of glucose concentration on OTC production and growth kinetics was studied intensively. The optimal glucose concentration in the medium was 15 g/L. Higher glucose concentrations supported higher biomass production by less volumetric and specific antibiotic production. Based on these data, cultivations were carried out at semi-industrial scale 15 L bioreactor in batch culture. At bioreactor level, cell growth and OTC production were higher compared to the shake flask culture by about 18 and 38%, respectively. During the bioreactor cultivation, glucose was totally consumed after only 48 h. Thus, the fed-batch experiment was designed for mono-glucose feeding and complete medium feeding to increase the OTC production by overcoming carbon limitations. The results showed that the fed-batch culture using constant glucose feeding strategy with rate of 0.33 g/L/h produced 1072 mg/L. On the other hand, feeding with complete medium resulted in 45% higher biomass but less OTC production by about 26% compared to mono-glucose fed culture. A further improvement in this process was achieved in by keeping the dissolved oxygen (DO value at 60% saturation by cascading the glucose feeding pump with the DO controller. The later feeding strategy resulted in higher antibiotic production, reaching 1414 mg/L after 108 h.

  14. Biological hydrogen production measured in batch anaerobic respirometers.

    Science.gov (United States)

    Logan, Bruce E; Oh, Sang-Eun; Kim, In S; Van Ginkel, Steven

    2002-06-01

    The biological production of hydrogen from the fermentation of different substrates was examined in batch tests using heat-shocked mixed cultures with two techniques: an intermittent pressure release method (Owen method) and a continuous gas release method using a bubble measurement device (respirometric method). Under otherwise identical conditions, the respirometric method resulted in the production of 43% more hydrogen gas from glucose than the Owen method. The lower conversion of glucose to hydrogen using the Owen protocol may have been produced by repression of hydrogenase activity from high partial pressures in the gastight bottles, but this could not be proven using a thermodynamic/rate inhibition analysis. In the respirometric method, total pressure in the headspace never exceeded ambient pressure, and hydrogen typically composed as much as 62% of the headspace gas. High conversion efficiencies were consistently obtained with heat-shocked soils taken at different times and those stored for up to a month. Hydrogen gas composition was consistently in the range of 60-64% for glucose-grown cultures during logarithmic growth but declined in stationary cultures. Overall, hydrogen conversion efficiencies for glucose cultures were 23% based on the assumption of a maximum of 4 mol of hydrogen/ mol of glucose. Hydrogen conversion efficiencies were similar for sucrose (23%) and somewhat lower for molasses (15%) but were much lower for lactate (0.50%) and cellulose (0.075%).

  15. Optimization of cyclosporin A production by Beauveria nivea in continuous fed-batch fermentation

    Directory of Open Access Journals (Sweden)

    Dong Huijun

    2011-01-01

    Full Text Available To develop the effective control method for fed-batch culture of cyclosporin A production, we chose fructose, L-valine and (NH42HPO4 as feeding nutrients and compared their productivities in relation to different concentrations. The feeding rate of three kinds of feeding materials was controlled to maintain the suitable residual concentration. The fed-batch fermentation results indicated that the optimal concentrations of fructose, L-valine and (NH42HPO4 were about 20 g/L, 0.5 g/L and 0.6 g/L for cyclosporin A production, respectively. The cultivation of Beauveria nivea could produce cyclosporin A up to 6.2 g/L for 240 hrs through a continuous feeding-rate-controlled-batch process under the optimal feeding conditions.

  16. Quantitative modeling of viable cell density, cell size, intracellular conductivity, and membrane capacitance in batch and fed-batch CHO processes using dielectric spectroscopy.

    Science.gov (United States)

    Opel, Cary F; Li, Jincai; Amanullah, Ashraf

    2010-01-01

    Dielectric spectroscopy was used to analyze typical batch and fed-batch CHO cell culture processes. Three methods of analysis (linear modeling, Cole-Cole modeling, and partial least squares regression), were used to correlate the spectroscopic data with routine biomass measurements [viable packed cell volume, viable cell concentration (VCC), cell size, and oxygen uptake rate (OUR)]. All three models predicted offline biomass measurements accurately during the growth phase of the cultures. However, during the stationary and decline phases of the cultures, the models decreased in accuracy to varying degrees. Offline cell radius measurements were unsuccessfully used to correct for the deviations from the linear model, indicating that physiological changes affecting permittivity were occurring. The beta-dispersion was analyzed using the Cole-Cole distribution parameters Deltaepsilon (magnitude of the permittivity drop), f(c) (critical frequency), and alpha (Cole-Cole parameter). Furthermore, the dielectric parameters static internal conductivity (sigma(i)) and membrane capacitance per area (C(m)) were calculated for the cultures. Finally, the relationship between permittivity, OUR, and VCC was examined, demonstrating how the definition of viability is critical when analyzing biomass online. The results indicate that the common assumptions of constant size and dielectric properties used in dielectric analysis are not always valid during later phases of cell culture processes. The findings also demonstrate that dielectric spectroscopy, while not a substitute for VCC, is a complementary measurement of viable biomass, providing useful auxiliary information about the physiological state of a culture.

  17. Monte Carlo simulation on kinetics of batch and semi-batch free radical polymerization

    KAUST Repository

    Shao, Jing

    2015-10-27

    Based on Monte Carlo simulation technology, we proposed a hybrid routine which combines reaction mechanism together with coarse-grained molecular simulation to study the kinetics of free radical polymerization. By comparing with previous experimental and simulation studies, we showed the capability of our Monte Carlo scheme on representing polymerization kinetics in batch and semi-batch processes. Various kinetics information, such as instant monomer conversion, molecular weight, and polydispersity etc. are readily calculated from Monte Carlo simulation. The kinetic constants such as polymerization rate k p is determined in the simulation without of “steady-state” hypothesis. We explored the mechanism for the variation of polymerization kinetics those observed in previous studies, as well as polymerization-induced phase separation. Our Monte Carlo simulation scheme is versatile on studying polymerization kinetics in batch and semi-batch processes.

  18. Batch process. Optimum designing and operation of a batch process; Bacchi purosesu

    Energy Technology Data Exchange (ETDEWEB)

    Hasebe, S. [Kyoto Univ. (Japan). Faculty of Engineering

    1997-09-05

    Since the control of a batch process becomes dynamic, it becomes necessary to handle the process differently from a continuous process in terms of the designing, operating and controlling of the process. This paper describes the characteristics and the problems to be solved of a batch process from three points of view, the designing, operation and controlling of the process. A major problem of a batch process is the designing difficulty. In a batch process, the amount of products capable of being manufactured per unit time by each apparatus and that by the whole plant structured by combining apparatuses are different, and therefore the time and apparatus capacity are wasted in some cases. The actual designing of a batch process involves various factors, such as the seasonal fluctuation of demand for products, the possibility of expanding the apparatuses in the future and the easiness of controlling the process, and the shipment of products during consecutive holidays and periodic maintenance, which are not included in the formulation of mathematical programming problems. Regarding the optimum operation of a batch process and the controlling of the same, descriptions of forming of a dynamic optimum operation pattern and verification of the sequence control system are given. 9 refs., 4 figs.

  19. Batch and fed-batch production of butyric acid by Clostridium butyricum ZJUCB

    Institute of Scientific and Technical Information of China (English)

    HE Guo-qing; KONG Qing; CHEN Qi-he; RUAN Hui

    2005-01-01

    The production of butyric acid by Clostridium butyricum ZJUCB at various pH values was investigated. In order to study the effect of pH on cell growth, butyric acid biosynthesis and reducing sugar consumption, different cultivation pH values ranging from 6.0 to 7.5 were evaluated in 5-L bioreactor. In controlled pH batch fermentation, the optimum pH for cell growth and butyric acid production was 6.5 with a cell yield of 3.65 g/L and butyric acid yield of 12.25 g/L. Based on these results, this study then compared batch and fed-batch fermentation of butyric acid production at pH 6.5. Maximum value (16.74 g/L) of butyric acid concentration was obtained in fed-batch fermentation compared to 12.25 g/L in batch fermentation. It was concluded that cultivation under fed-batch fermentation mode could enhance butyric acid production significantly (P<0.01) by C. butyricum ZJUCB.

  20. Using Forensics to Untangle Batch Effects in TCGA Data - TCGA

    Science.gov (United States)

    Rehan Akbani, Ph.D., and colleagues at the University of Texas MD Anderson Cancer Center developed a tool called MBatch to detect, diagnose, and correct batch effects in TCGA data. Read more about batch effects in this Case Study.

  1. Optimal operation of batch membrane processes

    CERN Document Server

    Paulen, Radoslav

    2016-01-01

    This study concentrates on a general optimization of a particular class of membrane separation processes: those involving batch diafiltration. Existing practices are explained and operational improvements based on optimal control theory are suggested. The first part of the book introduces the theory of membrane processes, optimal control and dynamic optimization. Separation problems are defined and mathematical models of batch membrane processes derived. The control theory focuses on problems of dynamic optimization from a chemical-engineering point of view. Analytical and numerical methods that can be exploited to treat problems of optimal control for membrane processes are described. The second part of the text builds on this theoretical basis to establish solutions for membrane models of increasing complexity. Each chapter starts with a derivation of optimal operation and continues with case studies exemplifying various aspects of the control problems under consideration. The authors work their way from th...

  2. Process Modeling for Batch Cooling Crystallization

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The general mathematical model for batch cooling crystallization was established based on the popula tion balance equation considering the change of slurry volume, and simulated with crystallization thermodynamics, kinetics and mass balance employing bed voidage. In the system of vitamin C-water-ethanol, reliability of this model was verified by comparison between simulation results and experimental data. The effects of operation parameters on product quality can be systematically investigated by modeling simulation.

  3. Process Modeling for Batch Cooling Crystallization

    Institute of Scientific and Technical Information of China (English)

    陈慧萍; 王静康

    2001-01-01

    The general mathematical model for batch cooling crystallization was established based on the population balance equation considering the change of slurry volume, and simulated with crystallization thermodynamics,kinetics and mass balance employing bed voidage. In the system of vitamin C-water-ethanol, reliability of this model was verified by comparison between simulation results and experimental data. The effects of operation parameters on product quality can be systematically investigated by modeling simulation.

  4. Pollution prevention applications in batch manufacturing operations

    Science.gov (United States)

    Sykes, Derek W.; O'Shaughnessy, James

    2004-02-01

    Older, "low-tech" batch manufacturing operations are often fertile grounds for gains resulting from pollution prevention techniques. This paper presents a pollution prevention technique utilized for wastewater discharge permit compliance purposes at a batch manufacturer of detergents, deodorants, and floor-care products. This manufacturer generated industrial wastewater as a result of equipment rinses required after each product batch changeover. After investing a significant amount of capital on end of pip-line wastewater treatment technology designed to address existing discharge limits, this manufacturer chose to investigate alternate, low-cost approaches to address anticipated new permit limits. Mass balances using spreadsheets and readily available formulation and production data were conducted on over 300 products to determine how each individual product contributed to the total wastewater pollutant load. These mass balances indicated that 22 products accounted for over 55% of the wastewater pollutant. Laboratory tests were conducted to determine whether these same products could accept their individual changeover rinse water as make-up water in formulations without sacrificing product quality. This changeover reuse technique was then implement at the plant scale for selected products. Significant reductions in wastewater volume (25%) and wastewater pollutant loading (85+%) were realized as a direct result of this approach.

  5. 40 CFR 63.1321 - Batch process vents provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents provisions. 63.1321... Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins § 63.1321 Batch process vents provisions. (a) Batch process vents. Except as specified in paragraphs (b) through (d) of this...

  6. Semiautomated, Reproducible Batch Processing of Soy

    Science.gov (United States)

    Thoerne, Mary; Byford, Ivan W.; Chastain, Jack W.; Swango, Beverly E.

    2005-01-01

    A computer-controlled apparatus processes batches of soybeans into one or more of a variety of food products, under conditions that can be chosen by the user and reproduced from batch to batch. Examples of products include soy milk, tofu, okara (an insoluble protein and fiber byproduct of soy milk), and whey. Most processing steps take place without intervention by the user. This apparatus was developed for use in research on processing of soy. It is also a prototype of other soy-processing apparatuses for research, industrial, and home use. Prior soy-processing equipment includes household devices that automatically produce soy milk but do not automatically produce tofu. The designs of prior soy-processing equipment require users to manually transfer intermediate solid soy products and to press them manually and, hence, under conditions that are not consistent from batch to batch. Prior designs do not afford choices of processing conditions: Users cannot use previously developed soy-processing equipment to investigate the effects of variations of techniques used to produce soy milk (e.g., cold grinding, hot grinding, and pre-cook blanching) and of such process parameters as cooking times and temperatures, grinding times, soaking times and temperatures, rinsing conditions, and sizes of particles generated by grinding. In contrast, the present apparatus is amenable to such investigations. The apparatus (see figure) includes a processing tank and a jacketed holding or coagulation tank. The processing tank can be capped by either of two different heads and can contain either of two different insertable mesh baskets. The first head includes a grinding blade and heating elements. The second head includes an automated press piston. One mesh basket, designated the okara basket, has oblong holes with a size equivalent to about 40 mesh [40 openings per inch (.16 openings per centimeter)]. The second mesh basket, designated the tofu basket, has holes of 70 mesh [70 openings

  7. Batch Model for Batched Timestamps Data Analysis with Application to the SSA Disability Program

    Science.gov (United States)

    Yue, Qingqi; Yuan, Ao; Che, Xuan; Huynh, Minh; Zhou, Chunxiao

    2016-01-01

    The Office of Disability Adjudication and Review (ODAR) is responsible for holding hearings, issuing decisions, and reviewing appeals as part of the Social Security Administration’s disability determining process. In order to control and process cases, the ODAR has established a Case Processing and Management System (CPMS) to record management information since December 2003. The CPMS provides a detailed case status history for each case. Due to the large number of appeal requests and limited resources, the number of pending claims at ODAR was over one million cases by March 31, 2015. Our National Institutes of Health (NIH) team collaborated with SSA and developed a Case Status Change Model (CSCM) project to meet the ODAR’s urgent need of reducing backlogs and improve hearings and appeals process. One of the key issues in our CSCM project is to estimate the expected service time and its variation for each case status code. The challenge is that the systems recorded job departure times may not be the true job finished times. As the CPMS timestamps data of case status codes showed apparent batch patterns, we proposed a batch model and applied the constrained least squares method to estimate the mean service times and the variances. We also proposed a batch search algorithm to determine the optimal batch partition, as no batch partition was given in the real data. Simulation studies were conducted to evaluate the performance of the proposed methods. Finally, we applied the method to analyze a real CPMS data from ODAR/SSA.

  8. BATCH-GE: Batch analysis of Next-Generation Sequencing data for genome editing assessment.

    Science.gov (United States)

    Boel, Annekatrien; Steyaert, Woutert; De Rocker, Nina; Menten, Björn; Callewaert, Bert; De Paepe, Anne; Coucke, Paul; Willaert, Andy

    2016-01-01

    Targeted mutagenesis by the CRISPR/Cas9 system is currently revolutionizing genetics. The ease of this technique has enabled genome engineering in-vitro and in a range of model organisms and has pushed experimental dimensions to unprecedented proportions. Due to its tremendous progress in terms of speed, read length, throughput and cost, Next-Generation Sequencing (NGS) has been increasingly used for the analysis of CRISPR/Cas9 genome editing experiments. However, the current tools for genome editing assessment lack flexibility and fall short in the analysis of large amounts of NGS data. Therefore, we designed BATCH-GE, an easy-to-use bioinformatics tool for batch analysis of NGS-generated genome editing data, available from https://github.com/WouterSteyaert/BATCH-GE.git. BATCH-GE detects and reports indel mutations and other precise genome editing events and calculates the corresponding mutagenesis efficiencies for a large number of samples in parallel. Furthermore, this new tool provides flexibility by allowing the user to adapt a number of input variables. The performance of BATCH-GE was evaluated in two genome editing experiments, aiming to generate knock-out and knock-in zebrafish mutants. This tool will not only contribute to the evaluation of CRISPR/Cas9-based experiments, but will be of use in any genome editing experiment and has the ability to analyze data from every organism with a sequenced genome. PMID:27461955

  9. BATCH-GE: Batch analysis of Next-Generation Sequencing data for genome editing assessment

    Science.gov (United States)

    Boel, Annekatrien; Steyaert, Woutert; De Rocker, Nina; Menten, Björn; Callewaert, Bert; De Paepe, Anne; Coucke, Paul; Willaert, Andy

    2016-01-01

    Targeted mutagenesis by the CRISPR/Cas9 system is currently revolutionizing genetics. The ease of this technique has enabled genome engineering in-vitro and in a range of model organisms and has pushed experimental dimensions to unprecedented proportions. Due to its tremendous progress in terms of speed, read length, throughput and cost, Next-Generation Sequencing (NGS) has been increasingly used for the analysis of CRISPR/Cas9 genome editing experiments. However, the current tools for genome editing assessment lack flexibility and fall short in the analysis of large amounts of NGS data. Therefore, we designed BATCH-GE, an easy-to-use bioinformatics tool for batch analysis of NGS-generated genome editing data, available from https://github.com/WouterSteyaert/BATCH-GE.git. BATCH-GE detects and reports indel mutations and other precise genome editing events and calculates the corresponding mutagenesis efficiencies for a large number of samples in parallel. Furthermore, this new tool provides flexibility by allowing the user to adapt a number of input variables. The performance of BATCH-GE was evaluated in two genome editing experiments, aiming to generate knock-out and knock-in zebrafish mutants. This tool will not only contribute to the evaluation of CRISPR/Cas9-based experiments, but will be of use in any genome editing experiment and has the ability to analyze data from every organism with a sequenced genome. PMID:27461955

  10. Is whole-culture synchronization biology's 'perpetual-motion machine'?

    Science.gov (United States)

    Cooper, Stephen

    2004-06-01

    Whole-culture or batch synchronization cannot, in theory, produce a synchronized culture because it violates a fundamental law that proposes that no batch treatment can alter the cell-age order of a culture. In analogy with the history of perpetual-motion machines, it is suggested that the study of these whole-culture 'synchronization' methods might lead to an understanding of general biological principles even though these methods cannot be used to study the normal cell cycle.

  11. Production of ethanol in batch and fed-batch fermentation of soluble sugar

    International Nuclear Information System (INIS)

    Keeping in view of the demand and need for alternate energy source, especially liquid fuels and the availability of raw materials in Pakistan, we have carried out biochemical and technological studies for ethanol through fermentation of renewable substrates. Molasses and sugar cane have been used as substrate for yeast fermentation. Selected yeast were used in both batch and semi continuous fermentation of molasses. Clarified dilute molasses were fermented with different strains of Saccharomyces cerevisiae. Ethanol concentration after 64 hours batch fermentation reached 9.4% with 90% yield based on sugar content. During feed batch system similar results were obtained after a fermentation cycle of 48 hours resulting in higher productivity. Similarly carbohydrates in fruit juices and hydro lysates of biomass can be economically fermented to ethanol to be used as feed stock for other chemicals. (author)

  12. Sojourn time distributions in a Markovian G-queue with batch arrival and batch removal

    Directory of Open Access Journals (Sweden)

    Yang Woo Shin

    1999-01-01

    Full Text Available We consider a single server Markovian queue with two types of customers; positive and negative, where positive customers arrive in batches and arrivals of negative customers remove positive customers in batches. Only positive customers form a queue and negative customers just reduce the system congestion by removing positive ones upon their arrivals. We derive the LSTs of sojourn time distributions for a single server Markovian queue with positive customers and negative customers by using the first passage time arguments for Markov chains.

  13. Transfer of Campylobacter from a Positive Batch to Broiler Carcasses of a Subsequently Slaughtered Negative Batch: A Quantitative Approach.

    Science.gov (United States)

    Seliwiorstow, Tomasz; Baré, Julie; Van Damme, Inge; Gisbert Algaba, Ignacio; Uyttendaele, Mieke; De Zutter, Lieven

    2016-06-01

    The present study was conducted to quantify Campylobacter cross-contamination from a positive batch of broiler chicken carcasses to a negative batch at selected processing steps and to evaluate the duration of this cross-contamination. During each of nine visits conducted in three broiler slaughterhouses, Campylobacter levels were determined on broiler carcasses originating from Campylobacter-negative batches processed immediately after Campylobacter-positive batches. Data were collected after four steps during the slaughter process (scalding, plucking, evisceration, and washing) at 1, 10, and 20 min after the start of the slaughter of the batches. Campylobacter levels in ceca of birds from Campylobacter-positive batches ranged from 5.62 to 9.82 log CFU/g. When the preceding positive batch was colonized at a low level, no (enumerable) carcass contamination was found in a subsequent negative batch. However, when Campylobacter levels were high in the positive batch, Campylobacter was found on carcasses of the subsequent negative batch but at levels significantly lower than those found on carcasses from the preceding positive batch. The scalding and the evisceration process contributed the least (< 1.5 log CFU/g) and the most (up to 4 log CFU/ g), respectively, to the Campylobacter transmission from a positive batch to a negative batch. Additionally, the number of Campylobacter cells transferred from positive to negative batches decreased over the first 20 min of sampling time. However, the reduction was slower than previously estimated in risk assessment studies, suggesting that pathogen transfer during crosscontamination is a complex process.

  14. PBSNG—Batch System for Farm Architecture

    Institute of Scientific and Technical Information of China (English)

    J.Fromm; K.Genser; 等

    2001-01-01

    FBSNG [1] is a redesigned version of Farm Batch System (FBS[1]),which was developed as a batch process management system for off-line Run II data processing at FNAL.FBSNG is designed for UNIX computer farms and is capable of managing up to 1000 nodes in a single farm.FBSNG allows users to start arrays of parallel processes on one or more farm computers,It uses a simplified abstract resource counting method for load balancing between computers.The resource counting approach allows FBSNG to be a simple and flexible tool for farm resource management.FBSNG scheduler features include guaranteed and controllable” fair-share” scheduling.FBSNG is easily portable across different flavors of UNIX.The system has been successfully used at Fermilab as well as by off-site collaborators for several years on farms of different sizes and different platforms for off-line data processing,Monte-Carlo data generation and other tasks.

  15. Batch-to-batch pharmacokinetic variability confounds current bioequivalence regulations: A dry powder inhaler randomized clinical trial.

    Science.gov (United States)

    Burmeister Getz, E; Carroll, K J; Jones, B; Benet, L Z

    2016-09-01

    Current pharmacokinetic (PK) bioequivalence guidelines do not account for batch-to-batch variability in study design or analysis. Here we evaluate the magnitude of batch-to-batch PK variability for Advair Diskus 100/50. Single doses of fluticasone propionate and salmeterol combinations were administered by oral inhalation to healthy subjects in a randomized clinical crossover study comparing three different batches purchased from the market, with one batch replicated across two treatment periods. All pairwise comparisons between different batches failed the PK bioequivalence statistical test, demonstrating substantial PK differences between batches that were large enough to demonstrate bio-inequivalence in some cases. In contrast, between-replicate PK bioequivalence was demonstrated for the replicated batch. Between-batch variance was ∼40-70% of the estimated residual error. This large additional source of variability necessitates re-evaluation of bioequivalence assessment criteria to yield a result that is both generalizable and consistent with the principles of type I and type II error rate control. PMID:27037630

  16. Melting Properties of Loose and Granulated Glass Batch

    Institute of Scientific and Technical Information of China (English)

    WANG Jing; DENG Zhenglu; XIE Jun; CHENG Jinshu; HAN Jianjun; ZHOU Xuedong

    2014-01-01

    The physical properties, the pre-reacting performance and melting properties of the loose glass batch and the granulated glass batch were investigated, respectively. The experimental results showed that compacted glass batch could reduce dust, use ultra-fine powder, and improve heat transfer efficiency. When loose glass batch was compressed into granular, the thermal conductivity was increased from 0.273 W/m•℃to 0.430 W/m•℃, the activation energy Ea of pre-reacting decreased from 178.77 kJ/mol to 143.30 kJ/mol. Using the pre-reacted granular glass batch can significantly reduce the melting time, increase the batch melting rate, and decrease the heat consumption of 1kg molten glass from 3591.24 to 3277.03kJ/kg.

  17. Adaptive quality prediction of batch processes based on PLS model

    Institute of Scientific and Technical Information of China (English)

    LI Chun-fu; ZHANG Jie; WANG Gui-zeng

    2006-01-01

    There are usually no on-line product quality measurements in batch and semi-batch processes,which make the process control task very difficult.In this paper,a model for predicting the end-product quality from the available on-line process variables at the early stage of a batch is developed using partial least squares (PLS)method.Furthermore,some available mid-course quality measurements are used to rectify the final prediction results.To deal with the problem that the process may change with time,recursive PLS (RPLS) algorithm is used to update the model based on the new batch data and the old model parameters after each batch.An application to a simulated batch MMA polymerization process demonstrates the effectiveness of the proposed method.

  18. Production of Medium-Chain-Length Poly(3-Hydroxyalkanoates from Saponified Palm Kernel Oil by Pseudomonas putida: Kinetics of Batch and Fed-Batch Fermentations

    Directory of Open Access Journals (Sweden)

    Annuar, M. S. M.

    2006-01-01

    Full Text Available The kinetics of medium-chain-length poly(3-hydroxyalkanoates, PHAMCL production by Pseudomonas putida PGA1 in batch and fed-batch fermentations were studied. With saponified palm kernel oil (SPKO supplying the free fatty acids mixture as the sole carbon and energy source, PHAMCL accumulation is encouraged under ammonium-limited condition, which is a nitrogen stress environment. The amount of PHAMCL accumulated and its specific production rate, qPHA were influenced by the residual ammonium concentration level in the culture medium. It was observed that in both fermentation modes, when the residual ammonium was exhausted (< 0.05 gL-1, the PHAMCL accumulation (11.9% and qPHA (0.0062 h-1 were significantly reduced. However, this effect can be reversed by feeding low amount of ammonium to the culture, resulting in significantly improved PHAMCL yield (71.4% and specific productivity (0.6 h-1. It is concluded that the feeding of low ammonium concentration to the culture medium during the PHAMCL accumulation has a positive effect on sustaining the PHAMCL biosynthetic capability of the organism. It was also found that increasing SPKO concentration in the medium significantly reduced (up to 50% the volumetric oxygen transfer coefficient (KLa of the fermentation system.

  19. TANK 50 BATCH 0 SALTSTONE FORMULATION CONFIRMATION

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.

    2006-06-05

    Savannah River National Laboratory (SRNL) personnel were requested to confirm the Tank 50 Batch 0 grout formulation per Technical Task Request, SSF-TTR-2006-0001 (task 1 of 2) [1]. Earlier Batch 0 formulation testing used a Tank 50 sample collected in September 2005 and is described elsewhere [2]. The current testing was performed using a sample of Tank 50 waste collected in May 2006. This work was performed according to the Technical Task and Quality Assurance Plan (TT/QAP), WSRC-RP-2006-00594 [3]. The salt solution collected from Tank 50 in May 2006 contained approximately 3 weight percent more solids than the sample collected in September 2005. The insoluble solids took longer to settle in the new sample which was interpreted as indicating finer particles in the current sample. The saltstone formulation developed for the September 2005 Tank 50 Batch 0 sample was confirmed for the May 2006 sample with one minor exception. Saltstone prepared with the Tank 50 sample collected in May 2006 required 1.5 times more Daratard 17 set retarding admixture than the saltstone prepared with the September In addition, a sample prepared with lower shear mixing (stirring with a spatula) had a higher plastic viscosity (57 cP) than samples made with higher shear mixing in a blender (23cP). The static gel times of the saltstone slurries made with low shear mixing were also shorter ({approx}32 minutes) than those for comparable samples made in the blender ({approx}47 minutes). The addition of the various waste streams (ETP, HEU-HCAN, and GPE-HCAN) to Tank 50 from September 2005 to May 2006 has increased the amount of set retarder, Daratard 17, required for processing saltstone slurries through the Saltstone facility. If these streams are continued to be added to Tank 50, the quantity of admixtures required to maintain the same processing conditions for the Saltstone facility will probably change and additional testing is recommended to reconfirm the Tank 50 Saltstone formulation.

  20. ENGINEERING CONTRACT ON FY-2 BATCH 2 SATELLITES SIGNED

    Institute of Scientific and Technical Information of China (English)

    SunQing

    2004-01-01

    The signing ceremony of the Engineering Contract on FY-2 Batch 2 (FY-2 02) Satellites was held in Beijing by Commission of Science, Technology and Industry for National Defense (COSTIND) on August 31, 2004. The contract on the development and manufacture of FY-2 batch 2 satellites and the contract on the launch, test and control of FY-2 Batch 2 satellites were signed by China Meteorological Administration (CMA),

  1. ADVANCES ON BILINEAR MODELING OF BIOCHEMICAL BATCH PROCESSES

    OpenAIRE

    GONZÁLEZ MARTÍNEZ, JOSÉ MARÍA

    2015-01-01

    [EN] This thesis is aimed to study the implications of the statistical modeling approaches proposed for the bilinear modeling of batch processes, develop new techniques to overcome some of the problems that have not been yet solved and apply them to data of biochemical processes. The study, discussion and development of the new methods revolve around the four steps of the modeling cycle, from the alignment, preprocessing and calibration of batch data to the monitoring of batches trajectories....

  2. A Survey of Batch Cataloging Practices and Problems

    OpenAIRE

    Young, Philip

    2011-01-01

    Groups of bibliographic records are added to library catalogs with increasing frequency. Batch cataloging requires knowledge of bulk record transfer as well as current cataloging standards. While more efficient than cataloging items individually, batch cataloging requires different skills and creates new challenges. Responses to a wide-ranging online survey document the workload, tools, practices, and problems of batch cataloging. The unique characteristics of electronic resources affect many...

  3. A batch fabricated biomimetic dry adhesive

    Science.gov (United States)

    Northen, Michael T.; Turner, Kimberly L.

    2005-08-01

    The fine hair adhesive system found in nature is capable of reversibly adhering to just about any surface. This dry adhesive, best demonstrated in the pad of the gecko, makes use of a multilevel conformal structure to greatly increase inelastic surface contact, enhancing short range interactions and producing significant amounts of attractive forces. Recent work has attempted to reproduce and test the terminal submicrometre 'hairs' of the system. Here we report the first batch fabricated multi-scale conformal system to mimic nature's dry adhesive. The approach makes use of massively parallel MEMS processing technology to produce 20-150 µm platforms, supported by single slender pillars, and coated with ~2 µm long, ~200 nm diameter, organic looking polymer nanorods, or 'organorods'. To characterize the structures a new mesoscale nanoindenter adhesion test technique has been developed. Experiments indicate significantly improved adhesion with the multiscale system. Additional processing caused a hydrophilic to hydrophobic transformation of the surface and testing indicated further improvement in adhesion.

  4. Production of clavulanic acid and cephamycin C by Streptomyces clavuligerus under different fed-batch conditions

    Directory of Open Access Journals (Sweden)

    C. Bellão

    2013-06-01

    Full Text Available The effect of carbon source and feeding conditions on the production of clavulanic acid (CA and cephamycin C (CephC by Streptomyces clavuligerus was investigated. In fed-batch experiments performed with glycerol feeding, production of CA exceeded that of CephC, and reached 1022 mg.L-1. Highest CephC production (566.5 mg.L-1 was obtained in fed-batch cultivation with glycerol feeding. In fed-batch experiments performed with starch feeding, the production of CephC was in general higher than that of CA. A dissociation index (DI was used to identify feeding conditions that favored production of CephC relative to CA. In all cultures with glycerol, DI values were less than unity, indicating higher production of CA compared to CephC. Conversely, in cultures fed with starch, the DI values obtained were greater than unity. However, no carbon source or feeding condition was able to completely dissociate the production of CA from that of CephC.

  5. A predictive and feedback control algorithm maintains a constant glucose concentration in fed-batch fermentations.

    Science.gov (United States)

    Kleman, G L; Chalmers, J J; Luli, G W; Strohl, W R

    1991-04-01

    A combined predictive and feedback control algorithm based on measurements of the concentration of glucose on-line has been developed to control fed-batch fermentations of Escherichia coli. The predictive control algorithm was based on the on-line calculation of glucose demand by the culture and plotting a linear regression to the next datum point to obtain a predicted glucose demand. This provided a predictive "coarse" control for the glucose-based nutrient feed. A direct feedback control using a proportional controller, based on glucose measurements every 2 min, fine-tuned the feed rate. These combined control schemes were used to maintain glucose concentrations in fed-batch fermentations as tight as 0.49 +/- 0.04 g/liter during growth of E. coli to high cell densities. PMID:2059049

  6. Unusal pattern of product inhibition: batch acetic acid fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Bar, R.; Gainer, J.L.; Kirwan, D.J.

    1987-04-20

    The limited tolerance of microorganisms to their metabolic products results in inhibited growth and product formation. The relationship between the specific growth rate, micro, and the concentration of an inhibitory product has been described by a number of mathematical models. In most cases, micro was found to be inversely proportional to the product concentration and invariably the rate of substrate utilization followed the same pattern. In this communication, the authors report a rather unusual case in which the formation rate of a product, acetic acid, increased with a decreasing growth rate of the microorganism, Acetobacter aceti. Apparently, a similar behavior was mentioned in a review report with respect to Clostridium thermocellum in a batch culture but was not published in the freely circulating literature. The fermentation of ethanol to acetic acid, C/sub 2/H/sub 5/OH + O/sub 2/ = CH/sub 3/COOH + H/sub 2/O is clearly one of the oldest known fermentations. Because of its association with the commercial production of vinegar it has been a subject of extensive but rather technically oriented studies. Suprisingly, the uncommon uncoupling between the inhibited microbial growth and the product formation appears to have been unnoticed. 13 references.

  7. Biodegradation of phenanthrene in an anaerobic batch reactor: growth kinetics

    Directory of Open Access Journals (Sweden)

    H.S. Nasrollahzadeh

    2010-07-01

    Full Text Available The purpose of the present research was to demonstrate the ability of mixed consortia of microorganisms to degrade high concentrations of phenanthrene (PHE as the sole carbon source. Batch experiments were carried out by the induction of mineral salt medium containing PHE to the seed culture and monitoring PHE biodegradation. The microbial propagation was conducted using PHE concentrations in the range of 20 to 100 mg/l. The microbial growth on PHE was defined based on Monod and modified Logistic rate models. The kinetic studies revealed that maximum specific growth rates (μm for PHE concentrations of 20, 50 and 100 mg/l were 0.12, 0.23 and 0.035 h-1, respectively. The doubling times for microbial population in PHE concentrations of 20, 50 and 100 mg/l were 13, 15 and 17.5 h, respectively. Also, maximum cell dry weight (xm of 54.23 mg/l was achieved, while the inhibition coefficient was 0.023 h-1. It was observed that the experimental data were well represented by the proposed models. It was also found that the biodegradation of PHE was successfully performed by the isolated strains.

  8. Batch process. Batch process used in a beer brewery; Biru kojo no bacchi purosesu

    Energy Technology Data Exchange (ETDEWEB)

    Kihara, K. [Kirin Engneering Co. Ltd. (Japan)

    1997-09-05

    In a beer brewing process, there is a system in which unit operation of chemical engineering is combined with the techniques of food and fermentation engineering in order to brew beer meeting the quality concept. This paper introduces the characteristics of a batch system used in the brewing of beer and the control method for the brewing of beer. The characteristics of the batch system used in a beer brewing process are the following three. In order to minimize the quality variation ascribed to the raw materials and the process, the materials are blended in various parts of the system. In the saccharification step which determines the quality of beer, two methods, i.e. a batch method and a continuous method are used, and beer brewing companies employ a saccharification system meeting the condition for attaining a desired quality of their own products. Two mashing systems are operated at different cycles shifted by half cycle from each other, not starting both at a time, so as to level the peaks of the utilities, whereby the operation of the utility-related facility is optimized. 1 ref., 2 figs., 1 tab.

  9. Comparison of Reductive Dechlorination of Chlorinated Ethylene in Batch and Continuous-Flow Reactor

    Science.gov (United States)

    Park, S.; Jonghwan, L.; Hong, U.; Kim, N.; Ahn, H.; Lee, S.; Kim, Y.

    2010-12-01

    A 1.28 L-Batch reactor and continuous-flow stirred tank reactor (CFSTR) fed with formate and trichloriethene (TCE) were operated for 120 days and 72 days, respectively, to study the effect of formate as electron donor on reductive dechlorination of TCE to cis-1,2-dichloroethylene (c-DCE), vinyl chloride (VC), and ethylene (ETH). In batch reactor, injected 60 μmol TCE was completely degraded in presence of 20% hydrogen gas (H2) in less than 8 days by Evanite culture (300 mg-soluble protein) with ability to completely degrade tetrachloroethene (PCE) and TCE to ETH under anaerobic conditions. To determine the effect of formate as electron donor instead of H2, about 3 or 11 mmol of formate injected into batch-reactor every 15 days was enough to support H2 for dechlorination of c-DCE to VC and ETH. Soluble protein concentration of Evanite culture during the batch test increased from 300 mg to 688 mg for 120 days. In CFSTR test, TCE was fed continuously at 9.9 ppm (75.38 μmol/L) and the influent formate feed concentration increased stepwise from 1.3 mmol/L to 14.3 mmol/L. Injected TCE was accumulated at HRT 18 days for 13 days, but TCE was completed degraded at HRT 36 days without accumulation during left of experiment period, getting H2 from fermentative hydrogen production of injected formate. Although c-DCE was also accumulated for 23 days after CFSTR operation, it reached steady-state without accumulation in presence of excessive formate. However, since c-DCE in CFSTR was not completely dechlorinated, we will determine the transcriptional level of enzyme involved in reductive dechlorination of TCE, c-DCE, and VC in our future work.

  10. Improved batch correction in untargeted MS-based metabolomics

    NARCIS (Netherlands)

    Wehrens, Ron; Hageman, Jos A.; Eeuwijk, van Fred; Kooke, Rik; Flood, Pádraic J.; Wijnker, Erik; Keurentjes, Joost J.B.; Lommen, Arjen; Eekelen, van Henriëtte D.L.M.; Hall, Robert D.; Mumm, Roland; Vos, de Ric C.H.

    2016-01-01

    Introduction: Batch effects in large untargeted metabolomics experiments are almost unavoidable, especially when sensitive detection techniques like mass spectrometry (MS) are employed. In order to obtain peak intensities that are comparable across all batches, corrections need to be performed. S

  11. Adaptive scheduling of batch servers in flow shops

    NARCIS (Netherlands)

    van der Zee, D.J.

    2002-01-01

    Batch servicing is a common way of benefiting from economies of scale in manufacturing operations. Good examples of production systems that allow for batch processing are ovens found in the aircraft industry and in semiconductor manufacturing. In this paper we study the issue of dynamic scheduling o

  12. Communication and control in small batch part manufacturing

    NARCIS (Netherlands)

    Tiemersma, J.J.; Curtis, W.; Kals, H.J.J.

    1993-01-01

    This paper reports on the development of a real-time control network as an integrated part of a shop floor control system for small batch part manufacturing. The shop floor control system is called the production control system (PCS). The PCS aims at an improved control of small batch part manufactu

  13. Spatial and interannual variability in Baltic sprat batch fecundity

    DEFF Research Database (Denmark)

    Haslob, H.; Tomkiewicz, Jonna; Hinrichsen, H.H.;

    2011-01-01

    in the central Baltic Sea, namely the Bornholm Basin, Gdansk Deep and Southern Gotland Basin. Environmental parameters such as hydrography, fish condition and stock density were tested in order to investigate the observed variability in sprat fecundity. Absolute batch fecundity was found to be positively related...... to fish length and weight. Significant differences in absolute and relative batch fecundity of Baltic sprat among areas and years were detected, and could partly be explained by hydrographic features of the investigated areas. A non-linear multiple regression model taking into account fish length...... and ambient temperature explained 70% of variability in absolute batch fecundity. Oxygen content and fish condition were not related to sprat batch fecundity. Additionally, a negative effect of stock size on sprat batch fecundity in the Bornholm Basin was revealed. The obtained data and results are important...

  14. Dynamic Simulation of Batch Photocatalytic Reactor (BPR) for Wastewater Treatment

    Science.gov (United States)

    Dutta, Suman

    2012-08-01

    Reactive dyes discharged from dyehouse causes a serious environmental problem. UV/TiO2 photocatalysis has been employed effectively for these organic dyes removal from dye-house effluent. This process produces less amount of non-toxic final product. In this paper a photocatalytic reactor has been designed for Reactive red 198 (RR198) removal from aqueous solution. The reactor is operating in batch mode. After each batch, TiO2 catalyst has been separated and recycled in the next batch. Mathematical model equation of this batch photocatalytic reactor (BPR) has been developed considering Langmuir-Hinshelwood kinetics. Simulation of BPR has been carried out using fourth order Runge-Kutta (RK) method and fifth order RK method (Butcher method). This simulation results can be used to develop an automatic photocatlytic reactor for industrial wastewater treatment. Catalyst activity decay and its effect on each batch have been incorporated in this model.

  15. Effect of glass-batch makeup on the melting process

    Energy Technology Data Exchange (ETDEWEB)

    Hrma, Pavel R; Schweiger, Michael J; Humrickhouse, Carissa J; Moody, J Adam; Tate, Rachel M; Rainsdon, Timothy T; Tegrotenhuis, Nathan E; Arrigoni, Benjamin M; Marcial, Jose; Rodriguez, Carmen P; Tincher, Benjamin

    2010-03-29

    The response of a glass batch to heating is determined by the batch makeup and in turn determines the rate of melting. Batches formulated for a high-alumina nuclear waste to be vitrified in an all-electric melter were heated at a constant temperature-increase rate to determine changes in melting behavior in response to the selection of batch chemicals and silica grain-size as well as the addition of heat-generating reactants. The type of batch materials and the size of silica grains determine how much, if any, primary foam occurs during melting. Small quartz grains, 5-μm in size, caused extensive foaming because their major portion dissolved at temperatures <800°C, contributing to the formation of viscous glass-forming melt that trapped evolving batch gases. Primary foam did not occur in batches with larger quartz grains, ±75 μm in size, because their major portion dissolved at temperatures >800°C when batch gases no longer evolved. The exothermal reaction of nitrates with sucrose was ignited at a temperature as low as 160°C and caused a temporary jump in temperature of several hundred degrees. Secondary foam, the source of which is oxygen from redox reactions, occurred in all batches of a limited composition variation involving five oxides, B2O3, CaO, Li2O, MgO, and Na2O. The foam volume at the maximum volume-increase rate was a weak function of temperature and melt basicity. Neither the batch makeup nor the change in glass composition had a significant impact on the dissolution of silica grains. The impacts of primary foam generation on glass homogeneity and the rate of melting in large-scale continuous furnaces have yet to be established via mathematical modeling and melter experiments.

  16. Biodenitrification in Sequencing Batch Reactors. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Silverstein, J. [Colorado Univ., Boulder, CO (United States). Dept. of Civil, Environmental, and Architectural Engineering

    1996-01-23

    One plan for stabilization of the Solar Pond waters and sludges at Rocky Flats Plant (RFP), is evaporation and cement solidification of the salts to stabilize heavy metals and radionuclides for land disposal as low-level mixed waste. It has been reported that nitrate (NO{sub 3}{sub {minus}}) salts may interfere with cement stabilization of heavy metals and radionuclides. Therefore, biological nitrate removal (denitrification) may be an important pretreatment for the Solar Pond wastewaters at RFP, improving the stability of the cement final waste form, reducing the requirement for cement (or pozzolan) additives and reducing the volume of cemented low-level mixed waste requiring ultimate disposal. A laboratory investigation of the performance of the Sequencing Batch Reactor (SBR) activated sludge process developed for nitrate removal from a synthetic brine typical of the high-nitrate and high-salinity wastewaters in the Solar Ponds at Rocky Flats Plant was carried out at the Environmental Engineering labs at the University of Colorado, Boulder, between May 1, 1994 and October 1, 1995.

  17. Biodegradability of industrial textile wastewater - batch tests.

    Science.gov (United States)

    Paździor, Katarzyna; Klepacz-Smółka, Anna; Wrębiak, Julita; Liwarska-Bizukojć, Ewa; Ledakowicz, Stanisław

    2016-01-01

    Following new trends we applied oxygen uptake rate (OUR) tests as well as long-term tests (in two batch bioreactors systems) in order to assess the biodegradability of textile wastewater. Effluents coming from a dyeing factory were divided into two streams which differed in inorganic and organic contaminants loads. Usefulness of the stream division was proved. Biodegradation of the low-loaded stream led to over 97% reduction of biochemical oxygen demand (BOD5) together with 80% reduction of chemical oxygen demand (COD) and total organic carbon (TOC). Most of the controlled parameter values were below the levels allowed by legislation for influents to surface water, whereas the high-loaded stream was so contaminated with recalcitrant organic compounds that despite the reduction of BOD5 by over 95%, COD, TOC, total nitrogen and total phosphorus levels exceeded permissible values. OUR tests were aimed at determination of the following kinetic parameters: maximum specific growth rate (μMax), half-saturation constant, hydrolysis constant and decay coefficient for activated sludge biomass for both types of textile wastewater studied. The values of kinetic parameters will be applied in activated sludge models used for prediction and optimisation of biological treatment of textile wastewater. PMID:27642827

  18. Batch-to-batch learning for model-based control of process systems with application to cooling crystallization

    NARCIS (Netherlands)

    Forgione, M.

    2014-01-01

    From an engineering perspective, the term process refers to a conversion of raw materials into intermediate or final products using chemical, physical, or biological operations. Industrial processes can be performed either in continuous or in batch mode. There exist for instance continuous and batch

  19. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    Directory of Open Access Journals (Sweden)

    Gupta Rishi

    2012-03-01

    Full Text Available Abstract Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates.

  20. 40 CFR Table 7 to Subpart Jjj of... - Group 1 Batch Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Group 1 Batch Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and Reporting Requirements 7 Table 7 to Subpart JJJ... Table 7 to Subpart JJJ of Part 63—Group 1 Batch Process Vents and Aggregate Batch Vent...

  1. 40 CFR Table 6 to Subpart U of... - Group 1 Batch Front-End Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Group 1 Batch Front-End Process Vents and Aggregate Batch Vent Streams-Monitoring, Recordkeeping, and Reporting Requirements 6 Table 6 to... 6 to Subpart U of Part 63—Group 1 Batch Front-End Process Vents and Aggregate Batch Vent...

  2. Batch-specific discrimination using nuclear quadrupole resonance spectroscopy.

    Science.gov (United States)

    Kyriakidou, Georgia; Jakobsson, Andreas; Althoefer, Kaspar; Barras, Jamie

    2015-04-01

    In this paper, we report on the identification of batches of analgesic paracetamol (acetaminophen) tablets using nitrogen-14 nuclear quadrupole resonance spectroscopy ((14)N NQR). The high sensitivity of NQR to the electron charge distribution surrounding the quadrupolar nucleus enables the unique characterization of the crystal structure of the material. Two hypothesis were tested on batches of the same brand: the within the same batch variability and the difference between batches that varied in terms of their batch number and expiry date. The multivariate analysis of variance (MANOVA) did not provide any within-batches variations, indicating the natural deviation of a medicine manufactured under the same conditions. Alternatively, the statistical analysis revealed a significant discrimination between the different batches of paracetamol tablets. Therefore, the NQR signal is an indicator of factors that influence the physical and chemical integrity of the material. Those factors might be the aging of the medicine, the manufacturing, or storage conditions. The results of this study illustrate the potential of NQR as promising technique in applications such as detection and authentication of counterfeit medicines.

  3. Extracellular production of a glycolipid biosurfactant, mannosylerythritol lipid, by Candida sp. SY16 using fed-batch fermentation.

    Science.gov (United States)

    Kim, Hee-Sik; Jeon, Jong-Woon; Kim, Byung-Hyuk; Ahn, Chi-Yong; Oh, Hee-Mock; Yoon, Byung-Dae

    2006-04-01

    Candida sp. strain SY16 produces a glycolipid-type biosurfactant, mannosylerythritol lipid (MEL-SY16), which can reduce the surface tension of a culture broth from 72 to 30 dyne cm(-1) and highly emulsify hydrocarbons when cultured in soybean-oil-containing media. As such, laboratory-scale fermentation for MEL-SY16 production was performed using optimized conditions. In batch fermentation, MEL-SY16 was mainly produced during the stationary phase of growth, and the concentration of MEL-SY16 reached 37 g l(-1) after 200 h. The effect of pH control on the production of MEL-SY16 was also examined in batch fermentation. The highest production yield of MEL-SY16 was when the pH was controlled at 4.0, and the production was significantly improved compared to batch fermentation without pH control. In fed-batch fermentation, glucose and soybean oil (1:1, w/w) were used in combination as the initial carbon sources for cell growth, and soybean oil was used as the feeding carbon source during the MEL production phase. The feeding of soybean oil resulted in the disappearance of any foam and a sharp increase in the MEL production until 200 h, at which point the concentration of MEL-SY16 was 95 g l(-1). Among the investigated culture systems, the highest MEL-SY16 production and volumetric production rate were achieved with fed-batch fermentation. PMID:16133323

  4. Capacity planning for batch and perfusion bioprocesses across multiple biopharmaceutical facilities.

    Science.gov (United States)

    Siganporia, Cyrus C; Ghosh, Soumitra; Daszkowski, Thomas; Papageorgiou, Lazaros G; Farid, Suzanne S

    2014-01-01

    Production planning for biopharmaceutical portfolios becomes more complex when products switch between fed-batch and continuous perfusion culture processes. This article describes the development of a discrete-time mixed integer linear programming (MILP) model to optimize capacity plans for multiple biopharmaceutical products, with either batch or perfusion bioprocesses, across multiple facilities to meet quarterly demands. The model comprised specific features to account for products with fed-batch or perfusion culture processes such as sequence-dependent changeover times, continuous culture constraints, and decoupled upstream and downstream operations that permit independent scheduling of each. Strategic inventory levels were accounted for by applying cost penalties when they were not met. A rolling time horizon methodology was utilized in conjunction with the MILP model and was shown to obtain solutions with greater optimality in less computational time than the full-scale model. The model was applied to an industrial case study to illustrate how the framework aids decisions regarding outsourcing capacity to third party manufacturers or building new facilities. The impact of variations on key parameters such as demand or titres on the optimal production plans and costs was captured. The analysis identified the critical ratio of in-house to contract manufacturing organization (CMO) manufacturing costs that led the optimization results to favor building a future facility over using a CMO. The tool predicted that if titres were higher than expected then the optimal solution would allocate more production to in-house facilities, where manufacturing costs were lower. Utilization graphs indicated when capacity expansion should be considered. PMID:24376262

  5. FRIT DEVELOPMENT FOR SLUDGE BATCH 6

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.; Edwards, T.; Zamecnik, J.

    2010-05-13

    The Savannah River National Laboratory (SRNL) evaluated a large number of Sludge Batch 6 (SB6) composition projections to support frit optimization for SB6 vitrification at the Defense Waste Processing Facility (DWPF). The evaluations discussed in this report occurred over a period of about 4 months, and included about 40 composition projections, developed by both Savannah River Remediation (SRR) and SRNL. Paper study assessments were used to evaluate the sludge composition projections with arrays of potential frit compositions using the predictive models in the DWPF Product Composition Control System (PCCS). Both nominal sludge compositions and sludge compositions with anticipated compositional variation were considered. The model predictions were used to identify candidate frit compositions for each SB6 projection and to provide some guidance to SRR on washing and blending strategies for SB6 preparation. This report presents a chronological review of this process and summarizes the findings at each stage. Following initial feedback from this work, the number of washes in Tank 51 was reduced to increase the projected sodium concentration in SB6. Analyses of predicted frit performance before and after a potential decant of Tank 40 showed that the post-decant SB6 composition would be difficult to process with any frit composition and that this scenario should be avoided. Based on the most recent SB6 projections (February 2010 SB6 composition projections developed at SRNL using the measured SB6 qualification sample composition and the revised Tank Farm washing plan), Frit 418 appears to be viable for SB6 processing at a target waste loading of 36%. A Nominal Stage PCCS Measurement Acceptability Region (MAR) assessment gave projected operating windows of 25-41% waste loading, limited by predictions of nepheline crystallization. The projected operating window is reduced to 25-38% waste loading when anticipated compositional variation is considered, again limited by

  6. Ethanol production potential from fermented rice noodle wastewater treatment using entrapped yeast cell sequencing batch reactor

    Science.gov (United States)

    Siripattanakul-Ratpukdi, Sumana

    2012-03-01

    Fermented rice noodle production generates a large volume of starch-based wastewater. This study investigated the treatment of the fermented rice noodle wastewater using entrapped cell sequencing batch reactor (ECSBR) compared to traditional sequencing batch reactor (SBR). The yeast cells were applied because of their potential to convert reducing sugar in the wastewater to ethanol. In present study, preliminary treatment by acid hydrolysis was performed. A yeast culture, Saccharomyces cerevisiae, with calcium alginate cell entrapment was used. Optimum yeast cell loading in batch experiment and fermented rice noodle treatment performances using ECSBR and SBR systems were examined. In the first part, it was found that the cell loadings (0.6-2.7 × 108 cells/mL) did not play an important role in this study. Treatment reactions followed the second-order kinetics with the treatment efficiencies of 92-95%. In the second part, the result showed that ECSBR performed better than SBR in both treatment efficiency and system stability perspectives. ECSBR maintained glucose removal of 82.5 ± 10% for 5-cycle treatment while glucose removal by SBR declined from 96 to 40% within the 5-cycle treatment. Scanning electron microscopic images supported the treatment results. A number of yeast cells entrapped and attached onto the matrix grew in the entrapment matrix.

  7. Batch cooling crystallization and pressure filtration of sulphathiazole

    DEFF Research Database (Denmark)

    Häkkinen, Antti; Pöllänen, Kati; Karjalainen, Milja;

    2005-01-01

    crystal suspensions obtained through an unseeded batch-cooling-crystallization process was studied. Sulphathiazole, which is an antibiotic agent with multiple polymorphic forms, was produced by performing laboratory-scale cooling crystallization experiments from five different mixtures of water and propan...... the samples obtained from different solvents. The crystals produced in the batch-cooling-crystallization experiments were separated from the crystallizing solvents using a batch-type pressure Nutsche filter, and the filtration characteristics of the suspensions were evaluated on the basis of average filter...

  8. A New Batch Verifying Scheme for Identifying Illegal Signatures

    Institute of Scientific and Technical Information of China (English)

    Adrian Atanasiu

    2013-01-01

    The concept of batch verifying multiple digital signatures is to find a method by which multiple digital signatures can be verified simultaneously in a lower time complexity than separately verifying all the signatures.In this article,we analyze the complexity of the batch verifying schemes defined by Li,Hwang and Chen in 2010,and propose a new batch verifying multiple digital signature scheme,in two variants:one for RSA-by completing the Harn's schema with an identifying illegal signatures algorithm,and the other adapted for a modified Elliptic Curve Digital Signature Algorithm protocol.

  9. Nitrifying and denitrifying bacteria in aerobic granules formed in sequencing batch airlift reactors

    Institute of Scientific and Technical Information of China (English)

    WANG Fang; YANG Fenglin; QI Aijiu

    2007-01-01

    The purpose of this study was to investigate nitrifying bacteria and denitrifying bacteria isolated from aerobic granules.Aerobic granules were formed in an internal-circulate sequencing batch airlift reactor(SBAR)and biodegradation of NH3 -N was analyzed in the reactor.Bacteria were isolated and determined from aerobic granules using selected media.The growth properties and morphology of bacteria colonies were observed by controlling aerobic or anaerobic conditions in the culture medium.It was found that bacteria in aerobic granules were diverse and some of them were facultative aerobes.The diversity of bacteria in aerobic granules was a premise of simultaneous nitrification and denitrification.

  10. Benchmarking of commercially available CHO cell culture media for antibody production

    OpenAIRE

    Reinhart, David; Damjanovic, Lukas; Kaisermayer, Christian; Kunert, Renate

    2015-01-01

    In this study, eight commercially available, chemically defined Chinese hamster ovary (CHO) cell culture media from different vendors were evaluated in batch culture using an IgG-producing CHO DG44 cell line as a model. Medium adaptation revealed that the occurrence of even small aggregates might be a good indicator of cell growth performance in subsequent high cell density cultures. Batch experiments confirmed that the culture medium has a significant impact on bioprocess performance, but hi...

  11. Batch phenol biodegradation study and application of factorial experimental design

    Directory of Open Access Journals (Sweden)

    A. Hellal

    2010-01-01

    Full Text Available A bacterium, Pseudomonas aeruginosa (ATTC27853, was investigated for its ability to grow and to degrade phenol as solecarbon source, in aerobic batch culture. The parameters which affect the substrate biodegradation such as the adaptation ofbacteria to phenol, the temperature, and the nature of the bacteria were investigated. The results show that for a range oftemperature of 30 to 40°C, the best degradation of phenol for a concentration of 100mg/l was observed at 30°C. The regenerationof the bacterium which allows the reactivation of its enzymatic activity, shows that the degradation of 100 mg/ l ofsubstrate at 30° C required approximately 50 hours with revivified bacteria, while it only starts after 72 hours for those norevivified. Adapted to increasing concentrations, allows the bacteria to degrade a substrate concentration of about 400mg/l in less than 350 hours.A second part was consisted in the determination of a substrate degradation model using the factorial experiment design,as a function of temperature (30-40°C and of the size of the inoculums (260.88 - 521.76mg/ l. The results were analyzedstatistically using the Student’s t-test, analysis of variance, and F-test. The value of R2 (0.99872 and adjusted R2 (0.9962close to 1.0, verifies the good correlation between the observed and the predicted values, and provides the excellent relationshipbetween the independent variables (factors and the response (the time of the phenol degradation. F-value found above200, indicates that the considered model is statistically significant.

  12. Optimal configuration, design and operation of batch distillation processes

    OpenAIRE

    Low, K. H.

    2003-01-01

    The overall objective of this thesis is to study the optimal configuration. design and operating policy of batch distillation processes in different separation scenarios. In so doing, this work also aims to provide conceptual insights and compare the performance of the traditional regular column against unconventional columns. In the first part of the thesis, the optimal operation of extractive batch distillation is investigated. A rigorous dynamic optimisation approach based o...

  13. Optimal control of a fed-batch fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Dekkers, R.M.

    1984-01-01

    The common cultivation of bakers' yeast is an aerobic fed-batch fermentation under sugar-limited growth. The ultimate objective of on-line computer control is to optimize the process through maximizing the productivity of biomass formation while minimizing the consumption of raw materials for the product. Results obtained on the optimal control of a fed-batch fermentation are given. The aspects to be considered are instrumentation, state estimation, optimization and process control.

  14. Differences of silicon photodiode spectral reflectance among the same batch

    Institute of Scientific and Technical Information of China (English)

    A.L.Mu(n)oz Zurita; J.Campos Acosta; A.Pons Aglio; A.Shcherbakov

    2008-01-01

    Photodiode's reflectance plays an important role regarding the relation between responsivity and the incident flux. In this work we analyze how the spectral reflectance changes among photodiodes from the same manufacturer and batch and how the reflectance of three standard photodiodes has drifted during six years. The results show that the reflectance changes from diode to diode within the same batch and also show th.at the reflectance ofphotodiodes changes on time. This ageing is spectrally dependent.

  15. Dynamic Extensions of Batch Systems with Cloud Resources

    International Nuclear Information System (INIS)

    Compute clusters use Portable Batch Systems (PBS) to distribute workload among individual cluster machines. To extend standard batch systems to Cloud infrastructures, a new service monitors the number of queued jobs and keeps track of the price of available resources. This meta-scheduler dynamically adapts the number of Cloud worker nodes according to the requirement profile. Two different worker node topologies are presented and tested on the Amazon EC2 Cloud service.

  16. Shortcut Algorithm for Simulation of Batch Extractive Distillation

    Institute of Scientific and Technical Information of China (English)

    WU Huixiong; XU Shimin; HU Hui; XIAO Bin

    2007-01-01

    The batch extractive distillation (BED) process has the advantages of both batch and extractive distillation. It is one of the most promising means for the separation of azeotropic and close-boiling point systems. However, so far this process has not been applied in industry due to its over-complexity. A new shortcut model was proposed to simulate the operation of the batch extractive distillation operations. This algorithm is based on the assumption that the batch extractive distillation column can be considered as a continuous extractive distillation column with changing feed at anytime. Namely, the whole batch process is simulated as a succession of a finite number of steady states of short duration, in which holdup is considered as constant mole. For each period of time the batch extractive distillation process is solved through the algorithm for continuous extractive distillation. Finally, the practical implementation of the shortcut model is discussed and data from the lab-oratory and literature are presented. It is found that this model has better adaptability, more satisfactory accuracy and less calculative load than previous rigorous model. Hence the algorithm for simulating BED is verified.

  17. Batch process monitoring based on multilevel ICA-PCA

    Institute of Scientific and Technical Information of China (English)

    Zhi-qiang GE; Zhi-huan SONG

    2008-01-01

    In this paper,we describe a new batch process monitoring method based on multilevel independent component analysis and principal component analysis (MLICA-PCA).Unlike the conventional multi-way principal component analysis (MPCA) method,MLICA-PCA provides a separated interpretation for multilevel batch process data.Batch process data are partitioned into two levels:the within-batch level and the between-batch level.In each level,the Gaussian and non-Ganssian components of process information can be separately extracted.I2,T2 and SPE statistics are individually built and monitored.The new method facilitates fault diagnosis.Since the two variation levels arc decomposed,the variables responsible for faults in each level can be identified and interpreted more easily.A case study of the Dupont benchmark process showed that the proposed method was more efficient and interpretable in fault detection and diagnosis,compared to the alternative batch process monitoring method.

  18. OPLS in batch monitoring - Opens up new opportunities.

    Science.gov (United States)

    Souihi, Nabil; Lindegren, Anders; Eriksson, Lennart; Trygg, Johan

    2015-02-01

    In batch statistical process control (BSPC), data from a number of "good" batches are used to model the evolution (trajectory) of the process and they also define model control limits, against which new batches may be compared. The benchmark methods used in BSPC include partial least squares (PLS) and principal component analysis (PCA). In this paper, we have used orthogonal projections to latent structures (OPLS) in BSPC and compared the results with PLS and PCA. The experimental study used was a batch hydrogenation reaction of nitrobenzene to aniline characterized by both UV spectroscopy and process data. The key idea is that OPLS is able to separate the variation in data that is correlated to the process evolution (also known as 'batch maturity index') from the variation that is uncorrelated to process evolution. This separation of different types of variations can generate different batch trajectories and hence lead to different established model control limits to detect process deviations. The results demonstrate that OPLS was able to detect all process deviations and provided a good process understanding of the root causes for these deviations. PCA and PLS on the other hand were shown to provide different interpretations for several of these process deviations, or in some cases they were unable to detect actual process deviations. Hence, the use of OPLS in BSPC can lead to better fault detection and root cause analysis as compared to existing benchmark methods and may therefore be used to complement the existing toolbox. PMID:25604817

  19. [Characteristic of Particulate Emissions from Concrete Batching in Beijing].

    Science.gov (United States)

    Xue, Yi-feng; Zhou, Zhen; Zhong, Lian-hong; Yan, Jing; Qu, Song; Huang, Yu-hu; Tian, He- zhong; Pan, Tao

    2016-01-15

    With the economic development and population growth in Beijing, there is a strong need for construction and housing, which leads to the increase of the construction areas. Meanwhile, as a local provided material, the production of concrete has been raised. In the process of concrete production by concrete batching, there are numerous particulates emitted, which have large effect on the atmospheric environment, however, systematic study about the tempo-spatial characteristics of pollutant emission from concrete batching is still rare. In this study, we estimated the emission of particulates from concrete batching from 1991 to 2012 using emission factor method, analyzed the tempo-spatial characteristics of pollutant emission, established the uncertainty range by adopting Monte-Carlo method, and predicted the future emission in 2020 based on the relative environmental and economical policies. The results showed that: (1) the emissions of particulates from concrete batching showed a trend of "first increase and then decrease", reaching the maximum in 2005, and then decreased due to stricter emission standard and enhanced environmental management. (2) according to spatial distribution, the emission of particulates from concrete batch mainly concentrated in the urban area with more human activities, and the area between the fifth ring and the sixth ring contributed the most. (3) through scenarios analysis, for further reducing the emission from concrete batching in 2020, more stricter standard for green production as well as powerful supervision is needed.

  20. Fungal morphology and fragmentation behavior in a fed-batch Aspergillus oryzae fermentation at the production scale.

    Science.gov (United States)

    Li, Z J; Shukla, V; Fordyce, A P; Pedersen, A G; Wenger, K S; Marten, M R

    2000-11-01

    It is well known that high-viscosity fermentation broth can lead to mixing and oxygen mass transfer limitations. The seemingly obvious solution for this problem is to increase agitation intensity. In some processes, this has been shown to damage mycelia, affect morphology, and decrease product expression. However, in other processes increased agitation shows no effect on productivity. While a number of studies discuss morphology and fragmentation at the laboratory and pilot scale, there are relatively few publications available for production-scale fungal fermentations. The goal of this study was to assess morphology and fragmentation behavior in large-scale, fed-batch, fungal fermentations used for the production of protein. To accomplish this, a recombinant strain of Aspergillus oryzae was grown in 80 m(3) fermentors at two different gassed, impeller power-levels (one 50% greater than the other). Impeller power is reported as energy dissipation/circulation function (EDCF) and was found to have average values of 29.3 +/- 1.0 and 22.0 +/- 0.3 kW m(-3) s(-1) at high and low power levels, respectively. In all batches, biomass concentration profiles were similar and specific growth rate was batches, respectively. At the end of each batch, clumps accounted for only 25% of fungal biomass, most of which existed as small, sparsely branched, free hyphal elements. In all batches, fragmentation was found to dominate fungal growth and branching. We speculate that this behavior was due to slow growth of the culture during this fed-batch process. PMID:10992234

  1. Characterization of algal and microbial community growth in a wastewater treating batch photo-bioreactor inoculated with lake water

    OpenAIRE

    Krustok, Ivo; Odlare, Monica; M.A., Shabiimam; Truu, Jaak; Truu, Marika; Ligi, Teele; Nehrenheim, Emma

    2015-01-01

    Microalgae grown in photo-bioreactors can be a valuable source of biomass, especially when combined with wastewater treatment. While most published research has studied pure cultures, the consortia of algae and bacteria from wastewater have more complex community dynamics which affect both the biomass production and pollutant removal. In this paper we investigate the dynamics of algal and bacterial growth in wastewater treating batch photo-bioreactors. The photo-bioreactors were inoculated wi...

  2. A comparison of fatty acid composition and quality aspects of eggs and larvae from cultured and wild broodstock of common sole ( Solea solea L . )

    DEFF Research Database (Denmark)

    Lund, Ivar; Steenfeldt, Svend Jørgen; Suhr, Karin;

    2008-01-01

    Eggs from a F-1 cultured broodstock of sole were compared with eggs from wild-caught breeders throughout one spawning season, to evaluate if egg quality may be affected by culture-related conditions. Fourteen batches of eggs from cultured broodstock and 17 batches from wild-caught sole were compa...

  3. Comparisons between continuous and batch processing to produce clavulanic acid by Streptomyces clavuligerus

    Directory of Open Access Journals (Sweden)

    Álvaro Baptista-Neto

    2005-06-01

    Full Text Available The aim of the present work was to compare CA production in continuous culture with and without cell recycling and in batch process by Streptomyces clavuligerus. Continuous cultivations with high cell concentration using cell recycling were performed utilizing a hollow fiber ultrafiltration module to separate cells from the filtrate broth. The continuous cultures without cell recycling and the batch cultivations were performed conventionally. The highest productivity was attained in the continuous cultivation with cell recycling (22.2 mg.L-1.h-1. The highest CA concentration was obtained in the batch process (470 mg.L-1.h-1.O ácido clavulânico (AC é um importante inibidor de beta-lactamases, enzimas que degradampartir do metabolismo secundário do Streptomyces clavuligerus, bactéria filamentosa e estritamente aeróbia. Considerando que a velocidade de produção de metabólitos secundários está ligada à concentração celular, o presente trabalho teve como objetivo comparar a produção de AC nos processos contínuos com e sem reciclo celular e em batelada, realizando cultivos dessa bactéria com alta densidade celular. Para cumprir com o objetivo proposto, foram realizados experimentos em biorreator operando na forma contínua com reciclo utilizando-se um módulo de filtração tangencial de fibra oca para a separação celular. Os processos contínuos sem reciclo e em batelada foram realizados de forma convencional. A produtividade em AC no cultivo contínuo com reciclo celular (22,2 mg.L-1h-1 foi superior aos processos convencionais, apesar de obter-se maior concentração do produto (470 mg.L-1 em batelada.

  4. Effect of batch and fed-batch growth modes on biofilm formation by Listeria monocytogenes at different temperatures

    OpenAIRE

    Rodrigues, Diana Alexandra Ferreira; Almeida, Marta A. S.; Teixeira, P.; Oliveira, Rosário; Azeredo, Joana

    2009-01-01

    The influence of Listeria monocytogenes (L. monocytogenes) biofilm formation feeding conditions (batch and fed-batch) at different temperatures on biofilm biomass and activity was determined. Biofilm biomass and cellular metabolic activity were assessed by Crystal Violet (CV) staining and 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide inner salt (XTT) colorimetric method, respectively. Live/Dead staining was also performed in order to get microscopic visualization of ...

  5. Design and Application of Software Sensors in Batch and Fed-batch Cultivations during Recombinant Protein Expression in Escherichia coli

    OpenAIRE

    Warth, Benedikt

    2008-01-01

    Software sensors are a potent tool to improve biotechnological real time process monitoring and control. In the current project, algorithms for six partly novel, software sensors were established and tested in a microbial reactor system. Eight batch and two fed-batch runs were carried out with a recombinant Escherichia coli to investigate the suitability of the different software sensor models in diverse cultivation stages. Special respect was given to effects on the sensors after recombinant...

  6. SLUDGE BATCH 7B GLASS VARIABILITY STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, F.; Edwards, T.

    2011-10-25

    The Defense Waste Processing Facility (DWPF) is preparing to initiate processing Sludge Batch 7b (SB7b). In support of the upcoming processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frits 418 with a 6% Na{sub 2}O addition (26 wt% Na{sub 2}O in sludge) and 702 with a 4% Na{sub 2}O addition (24 wt% Na{sub 2}O in sludge) to process SB7b. This recommendation was based on assessments of the compositional projections for SB7b available at the time from the Savannah River Remediation (SRR). To support qualification of SB7b, SRNL executed a variability study to assess the applicability of the current durability models for SB7b. The durability models were assessed over the expected composition range of SB7b, including potential caustic additions, combined with Frits 702 and 418 over a 32-40% waste loading (WL) range. Thirty four glasses were selected based on Frits 418 and 702 coupled with the sludge projections with an additional 4-6% Na{sub 2}O to reflect the potential caustic addition. Six of these glasses, based on average nominal sludge compositions including the appropriate caustic addition, were developed for both Frit 418 and Frit 702 at 32, 36 and 40% WL to provide coverage in the center of the anticipated SB7b glass region. All glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). To comply with the DWPF Glass Product Control Program, a total of thirty four glasses were fabricated to assess the applicability of the current DWPF PCCS durability models. Based on the measured PCT response, all of the glasses were acceptable with respect to the Environmental Assessment (EA) benchmark glass regardless of thermal history. The NL[B] values of the SB7b variability study glasses were less than 1.99 g/L as compared to 16.695 g/L for EA. A small number of the D-optimally selected 'outer layer' extreme vertices (EV) glasses were not

  7. SLUDGE BATCH VARIABILITY STUDY WITH FRIT 418

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, F.; Edwards, T.

    2010-11-29

    The Defense Waste Processing Facility (DWPF) initiated processing Sludge Batch 6 (SB6) in the summer of 2010. In support of processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frit 418 to process SB6. This recommendation was based on assessments of the compositional projections for SB6 available at the time from the Liquid Waste Organization (LWO) and SRNL (using a model-based approach). To support qualification of SB6, SRNL executed a variability study to assess the applicability of the current durability models for SB6. The durability models were assessed over the expected Frit 418-SB6 composition range. Seventeen glasses were selected for the variability study based on the sludge projections used in the frit recommendation. Five of the glasses are based on the centroid of the compositional region, spanning a waste loading (WL) range of 32 to 40%. The remaining twelve glasses are extreme vertices (EVs) of the sludge region of interest for SB6 combined with Frit 418 and are all at 36% WL. These glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). After initiating the SB6 variability study, the measured composition of the SB6 Tank 51 qualification glass produced at the SRNL Shielded Cells Facility indicated that thorium was present in the glass at an appreciable concentration (1.03 wt%), which made it a reportable element for SB6. This concentration of ThO{sub 2} resulted in a second phase of experimental studies. Five glasses were formulated that were based on the centroid of the new sludge compositional region combined with Frit 418, spanning a WL range of 32 to 40%. These glasses were fabricated and characterized using chemical composition analysis and the PCT. Based on the measured PCT response, all of the glasses (with and without thorium) were acceptable with respect to the Environmental Assessment (EA) reference glass

  8. Butanol production by immobilised Clostridium acetobutylicum in repeated batch, fed-batch, and continuous modes of fermentation.

    Science.gov (United States)

    Dolejš, Igor; Krasňan, Vladimír; Stloukal, Radek; Rosenberg, Michal; Rebroš, Martin

    2014-10-01

    Clostridium acetobutylicum immobilised in polyvinylalcohol, lens-shaped hydrogel capsules (LentiKats(®)) was studied for production of butanol and other products of acetone-butanol-ethanol fermentation. After optimising the immobilisation protocol for anaerobic bacteria, continuous, repeated batch, and fed-batch fermentations in repeated batch mode were performed. Using glucose as a substrate, butanol productivity of 0.41 g/L/h and solvent productivity of 0.63 g/L/h were observed at a dilution rate of 0.05 h(-1) during continuous fermentation with a concentrated substrate (60 g/L). Through the process of repeated batch fermentation, the duration of fermentation was reduced from 27.8h (free-cell fermentation) to 3.3h (immobilised cells) with a solvent productivity of 0.77 g/L/h (butanol 0.57 g/L/h). The highest butanol and solvent productivities of 1.21 and 1.91 g/L/h were observed during fed-batch fermentation operated in repeated batch mode with yields of butanol (0.15 g/g) and solvents (0.24 g/g), respectively, produced per gram of glucose.

  9. Levan production by Zymomonas mobilis in batch and continuous fermentation systems.

    Science.gov (United States)

    Silbir, Selim; Dagbagli, Seval; Yegin, Sirma; Baysal, Taner; Goksungur, Yekta

    2014-01-01

    Levan production in batch and continuous fermentation systems by Zymomonas mobilis B-14023 was investigated. The culture medium used in both of the fermentation systems contained sucrose and various organic nitrogen sources. Maximum concentration of levan was produced with yeast extract among the nitrogen sources tested. Response surface methodology was used to investigate the effects of three factors on the concentration of levan in batch cultures of Z. mobilis. Maximum levan concentration was 40.2 g/L and this concentration was reached at the optimum levels of process variables, which were 299.1 g/L initial substrate concentration, 42.3 h incubation time, and initial pH 6.0. Continuous fermentation experiments were done in packed bed bioreactor using Ca-alginate immobilized Z. mobilis cells. The highest levan concentration (31.8 ± 0.21 g/L) was obtained at a dilution rate of 0.14 h(-1) while maximum volumetric productivity (6.556 g/(Lh)) was obtained at a dilution rate of 0.22 h(-1). Increasing the dilution rate resulted in decreased levan and increased residual sugar concentrations. PMID:24274530

  10. Evaluation of kojic acid production in a repeated-batch PCS biofilm reactor.

    Science.gov (United States)

    Liu, Jui-Ming; Yu, Ting-Chu; Lin, Shin-Ping; Hsu, Ren-Jun; Hsu, Kai-Di; Cheng, Kuan-Chen

    2016-01-20

    In this study, kojic acid, a secondary metabolite as an industrially important compound, was produced by Aspergillus oryzae (A. oryzae), which was immobilized in plastic composite support (PCS) bioreactor. Nitrogen deficient medium was applied to increase the production of KA in PCS-immobilized bioreactor. The efficiency of immobilized culture for kojic acid (KA) production and the effect of morphology of A. oryzae on KA production were evaluated. After three cycles of cultivation, 83.47 g/L of KA was produced in PCS bioreactor in nitrogen deficient medium with productivity of 3.09 g/L/d, which is higher than free suspension culture in batch fermentation. The morphology of A. oryzae mycelium changed under nitrogen starvation. Feather-like mycelium was observed with increasing KA production. RNA expression (kojA and kojT) results indicated that the nitrogen deficient environment had strong influence on KA production on the transcriptional level. PCS immobilized fermentation system, which allowed a repeated-batch fermentation with higher production and productivity, is a potential tool in industrial production of KA. PMID:26657710

  11. Feeding strategies for the enhanced production of α-arbutin in the fed-batch fermentation of Xanthomonas maltophilia BT-112.

    Science.gov (United States)

    Liu, Chunqiao; Zhang, Peng; Zhang, Shurong; Xu, Tao; Wang, Fang; Deng, Li

    2014-02-01

    To develop a cost-effective method for the enhanced production of α-arbutin using Xanthomonas maltophilia BT-112 as a biocatalyst, different fed-batch strategies such as constant feed rate fed-batch, constant hydroquinone (HQ) concentration fed-batch, exponential fed-batch and DO-control pulse fed-batch (DPFB) on α-arbutin production were investigated. The research results indicated that DPFB was an effective method for α-arbutin production. When fermentation with DO-control pulse feeding strategy to feed HQ and yeast extract was applied, the maximum concentrations of α-arbutin and cell dry weight were 61.7 and 4.21 g/L, respectively. The α-arbutin production was 394% higher than that of the control (batch culture) and the molar conversion yield of α-arbutin reached 94.5% based on the amount of HQ supplied (240 mM). Therefore, the results in this work provide an efficient and easily controlled method for industrial-scale production of α-arbutin.

  12. Microbial fed-batch production of 1,3-propanediol using raw glycerol with suspended and immobilized Klebsiella pneumoniae.

    Science.gov (United States)

    Jun, Sun-Ae; Moon, Chuloo; Kang, Cheol-Hee; Kong, Sean W; Sang, Byoung-In; Um, Youngsoon

    2010-05-01

    The production of 1,3-propanediol (1,3-PD) was investigated with Klebsiella pneumoniae DSM 4799 using raw glycerol without purification obtained from a biodiesel production process. Fed-batch cultures with suspended cells revealed that 1,3-PD production was more effective when utilizing raw glycerol than pure glycerol (productivity after 47 h of fermentation, 0.84 g L(-1) 1 h(-1) versus 1.51 g L(-1) h(-1) with pure and raw glycerol,respectively). In addition, more than 80 g/L of 1,3-PD was produced using raw glycerol;this is the highest 1,3-PD concentration reported thus far for K. pneumoniae using raw glycerol. Repeated fed-batch fermentation with cell immobilization in a fixed-bed reactor was performed to enhance 1,3-PD production. Production of 1,3-PD increased with the cycle number (1.06 g L(-1) h(-1) versus 1.61 g L(-1) h(-1) at the first and fourth cycle, respectively)due to successful cell immobilization. During 46 cycles of fed-batch fermentation taking place over 1,460 h, a stable and reproducible 1,3-PD production performance was observed with both pure and raw glycerol. Based on our results, repeated fed batch with immobilized cells is an efficient fermentor configuration, and raw glycerol can be utilized to produce 1,3-PD without inhibitory effects caused by accumulated impurities.

  13. 40 CFR 63.492 - Batch front-end process vents-reporting requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vents-reporting... Batch front-end process vents—reporting requirements. (a) The owner or operator of a batch front-end process vent or aggregate batch vent stream at an affected source shall submit the information...

  14. 40 CFR 63.1322 - Batch process vents-reference control technology.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents-reference control... Batch process vents—reference control technology. (a) Batch process vents. The owner or operator of a Group 1 batch process vent, as determined using the procedures in § 63.1323, shall comply with...

  15. 40 CFR 63.1327 - Batch process vents-reporting requirements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents-reporting... Batch process vents—reporting requirements. (a) The owner or operator of a batch process vent or aggregate batch vent stream at an affected source shall submit the information specified in paragraphs...

  16. 40 CFR 63.1326 - Batch process vents-recordkeeping provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents-recordkeeping... Batch process vents—recordkeeping provisions. (a) Group determination records for batch process vents... batch process vent subject to the group determination procedures of § 63.1323. Except for paragraph...

  17. 40 CFR 63.487 - Batch front-end process vents-reference control technology.

    Science.gov (United States)

    2010-07-01

    ... assumes that the batch unit operation is operating at the maximum design capacity of the EPPU for 12... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vents-reference... § 63.487 Batch front-end process vents—reference control technology. (a) Batch front-end process...

  18. Run-to-run product quality control of batch processes

    Institute of Scientific and Technical Information of China (English)

    JIA Li; SHI Ji-ping; CHENG Da-shuai; CHIU Min-sen

    2009-01-01

    Batch processes have been increasingly used in the production of low volume and high value added products.Consequently,optimization control in batch processes is crucial in order to derive the maximum benefit.In this paper,a run-to-run product quality control based on iterative learning optimization control is developed.Moreover,a rigorous theorem is proposed and proven in this paper,which states that the tracking error under the optimal iterative learning control (ILC) law can converge to zero.In this paper,a typical nonlinear batch continuous stirred tank reactor (CSTR) is considered,and the results show that the performance of trajectory tracking is gradually improved by the ILC.

  19. Batch Statistical Process Monitoring Approach to a Cocrystallization Process.

    Science.gov (United States)

    Sarraguça, Mafalda C; Ribeiro, Paulo R S; Santos, Adenilson O Dos; Lopes, João A

    2015-12-01

    Cocrystals are defined as crystalline structures composed of two or more compounds that are solid at room temperature held together by noncovalent bonds. Their main advantages are the increase of solubility, bioavailability, permeability, stability, and at the same time retaining active pharmaceutical ingredient bioactivity. The cocrystallization between furosemide and nicotinamide by solvent evaporation was monitored on-line using near-infrared spectroscopy (NIRS) as a process analytical technology tool. The near-infrared spectra were analyzed using principal component analysis. Batch statistical process monitoring was used to create control charts to perceive the process trajectory and define control limits. Normal and non-normal operating condition batches were performed and monitored with NIRS. The use of NIRS associated with batch statistical process models allowed the detection of abnormal variations in critical process parameters, like the amount of solvent or amount of initial components present in the cocrystallization.

  20. Biogas plasticization coupled anaerobic digestion: batch test results.

    Science.gov (United States)

    Schimel, Keith A

    2007-06-01

    Biogas has unique properties for improving the biodegradability of biomass solids during anaerobic digestion (AD). This report presents batch test results of the first investigation into utilizing biogas plasticization to "condition" organic polymers during active digestion of waste activated sludge (WAS). Preliminary design calculations based on polymer diffusion rate limitation are presented. Analysis of the 20 degrees C batch test data determined the first order (k(1)) COD conversion coefficient to be 0.167 day(-1) with a maximum COD utilization rate of 11.25 g L(-1) day(-1). Comparison of these batch test results to typical conventional AD performance parameters showed orders of magnitude improvement. These results show that biogas plasticization during active AD could greatly improve renewable energy yields from biomass waste materials such as MSW RDF, STP sludges, food wastes, animal manure, green wastes, and agricultural crop residuals. PMID:17054122

  1. Application of gain scheduling to the control of batch bioreactors

    Science.gov (United States)

    Cardello, Ralph; San, Ka-Yiu

    1987-01-01

    The implementation of control algorithms to batch bioreactors is often complicated by the inherent variations in process dynamics during the course of fermentation. Such a wide operating range may render the performance of fixed gain PID controllers unsatisfactory. In this work, a detailed study on the control of batch fermentation is performed. Furthermore, a simple batch controller design is proposed which incorporates the concept of gain-scheduling, a subclass of adaptive control, with oxygen uptake rate as an auxiliary variable. The control of oxygen tension in the biorector is used as a vehicle to convey the proposed idea, analysis and results. Simulation experiments indicate significant improvement in controller performance can be achieved by the proposed approach even in the presence of measurement noise.

  2. From Fed-batch to Continuous Enzymatic Biodiesel Production

    DEFF Research Database (Denmark)

    Price, Jason Anthony; Nordblad, Mathias; Woodley, John M.;

    2015-01-01

    In this this paper, we use mechanistic modelling to guide the development of acontinuous enzymatic process that is performed as a fed-batch operation. In this workwe use the enzymatic biodiesel process as a case study. A mechanistic model developedin our previous work was used to determine...... measured components (triglycerides, diglycerides, monoglycerides, free fatty acid and fatty acid methyl esters(biodiesel)) much better than using fed-batch data alone given the smaller residuals. We also observe a reduction in the correlation between the parameters.The model was then used to predict that 5...... reactors are required (with a combined residence time of 30 hours) to reach a final biodiesel concentration within 2 % of the95.6 mass % achieved in a fed-batch operation, for 24 hours....

  3. Batch Private Keys Generation for RSA in Security Communication Systems

    Institute of Scientific and Technical Information of China (English)

    CHEN Yun; CHEN Xin

    2005-01-01

    RSA public key cryptosystem is extensively used in information security systems.However, key generation for RSA cryptosystem requires multiplicative inversion over finite field, which has higher computational complexity, compared with either multiplication in common sense or modular multiplication over finite field. In order to improve the performance of key generation, we propose a batch private keys generation method in this paper. The method derives efficiency from cutting down multiplicative inversions over finite field. Theoretical analysis shows that the speed of batch private keys generation for s users is faster than that of s times solo private key generation. It is suitable for applications in those systems with large amount of users.

  4. Stochastic growth logistic model with aftereffect for batch fermentation process

    Energy Technology Data Exchange (ETDEWEB)

    Rosli, Norhayati; Ayoubi, Tawfiqullah [Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, Lebuhraya Tun Razak, 26300 Gambang, Pahang (Malaysia); Bahar, Arifah; Rahman, Haliza Abdul [Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Salleh, Madihah Md [Department of Biotechnology Industry, Faculty of Biosciences and Bioengineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia)

    2014-06-19

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits.

  5. Stochastic growth logistic model with aftereffect for batch fermentation process

    Science.gov (United States)

    Rosli, Norhayati; Ayoubi, Tawfiqullah; Bahar, Arifah; Rahman, Haliza Abdul; Salleh, Madihah Md

    2014-06-01

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits.

  6. Improved production of Pseudomonas sp. ECU1011 acetyl esterase by medium design and fed-batch fermentation.

    Science.gov (United States)

    Ju, Xin; Yu, Hui-Lei; Pan, Jiang; Xu, Jian-He

    2012-03-01

    We optimized culture medium and batch-fed fermentation conditions to enhance production of an acetyl esterase from Pseudomonas sp. ECU1011 (PSAE). This enzyme enantioselectively deacetylates α-acetoxyphenylacetic acid. The medium was redesigned by single-factor and statistical optimization. The addition of ZnSO(4) enhanced enzyme production by 37%. Yeast extract concentration was directly associated with the enzyme production. The fermentation was scaled up in a 5-l fermenter with the optimized medium, and the correlations between enzyme production and dissolved oxygen, pH, and feeding strategy were investigated. The fermentation process was highly oxygen-demanding, pH sensitive and mandelic acid-inducible. The fermentation pH was controlled at 7.5 by a pH and dissolved oxygen feedback strategy. Feeding mandelic acid as both a pH regulator and an enzyme inducer increased the enzyme production by 23%. The results of the medium redesign experiments were confirmed and explained in fed-batch culture experiments. Mathematical models describing the fermentation processes indicated that the enzyme production was strongly associated with cell growth. The optimized pH and dissolved oxygen stat fed-batch process resulted high volumetric production of PSAE (4166 U/l, 7.2-fold higher than the initial) without enantioselectivity decline. This process has potential applications for industrial production of chiral mandelic acid or its derivatives. PMID:21792565

  7. Analysis and modelling of the energy requirements of batch processes; Analyse und Modellierung des Energiebedarfes in Batch-Prozessen

    Energy Technology Data Exchange (ETDEWEB)

    Bieler, P.S.

    2002-07-01

    This intermediate report for the Swiss Federal Office of Energy (SFOE) presents the results of a project aiming to model the energy consumption of multi-product, multi-purpose batch production plants. The utilities investigated were electricity, brine and steam. Both top-down and bottom-up approaches are described, whereby top-down was used for the buildings where the batch process apparatus was installed. Modelling showed that for batch-plants at the building level, the product mix can be too variable and the diversity of products and processes too great for simple modelling. Further results obtained by comparing six different production plants that could be modelled are discussed. The several models developed are described and their wider applicability is discussed. Also, the results of comparisons made between modelled and actual values are presented. Recommendations for further work are made.

  8. Performance comparison of suspended bed and batch contactor chromatography.

    Science.gov (United States)

    Quiñones-García, I; Rayner, I; Levison, P R; Dickson, N; Purdom, G

    2001-01-26

    In some applications, the purification and recovery of biomolecules is performed via a cascade of batch adsorption and desorption stages using agitated contactors and related filtration devices. Suspended bed chromatography is a recent process-scale innovation that is applicable to these separations. This hybrid technique exploits the benefits of combining batch adsorption in an agitated contactor with elution in an enclosed column system. To some extent, the process is similar to batch contactor chromatography but can be fully contained and significantly quicker. The process has two steps; first the fluid containing the sample is mixed with the adsorbent in a stirred tank. Second, the slurry suspension is transferred directly into a specialized column, such as an IsoPak column. The media with the adsorbed product is formed as a packed bed, whilst the suspension liquid is passed out of the column. The product is then eluted from the packed bed utilizing standard column-chromatography techniques. The performance of the suspended bed and the agitated contactor operations are demonstrated both by full-scale experimental results and process simulations. The purification of ovalbumin from a hen-egg white feedstock by anion-exchange chromatography was used as a case study in order to prove the concept. With the availability of both pump-packed systems and shear-resistant media, suspended bed chromatography is a better alternative for a range of applications than the traditional batch separations using agitated contactors. PMID:11218119

  9. Adaptation to high throughput batch chromatography enhances multivariate screening.

    Science.gov (United States)

    Barker, Gregory A; Calzada, Joseph; Herzer, Sibylle; Rieble, Siegfried

    2015-09-01

    High throughput process development offers unique approaches to explore complex process design spaces with relatively low material consumption. Batch chromatography is one technique that can be used to screen chromatographic conditions in a 96-well plate. Typical batch chromatography workflows examine variations in buffer conditions or comparison of multiple resins in a given process, as opposed to the assessment of protein loading conditions in combination with other factors. A modification to the batch chromatography paradigm is described here where experimental planning, programming, and a staggered loading approach increase the multivariate space that can be explored with a liquid handling system. The iterative batch chromatography (IBC) approach is described, which treats every well in a 96-well plate as an individual experiment, wherein protein loading conditions can be varied alongside other factors such as wash and elution buffer conditions. As all of these factors are explored in the same experiment, the interactions between them are characterized and the number of follow-up confirmatory experiments is reduced. This in turn improves statistical power and throughput. Two examples of the IBC method are shown and the impact of the load conditions are assessed in combination with the other factors explored. PMID:25914370

  10. The second batch of environmental standard qualified list released

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The Ministry of Environmental Protection released the second batch of enterprises list that basically meet environment standards recently. Total 41 enterprises from 10 provinces and autonomous regions of Inner Mongolia, Jiangsu, Jiangxi, Sichuan, Gansu and so on are included in the list.

  11. A fixed-size batch service queue with vacations

    Directory of Open Access Journals (Sweden)

    Ho Woo Lee

    1996-01-01

    Full Text Available The paper deals with batch service queues with vacations in which customers arrive according to a Poisson process. Decomposition method is used to derive the queue length distributions both for single and multiple vacation cases. The authors look at other decomposition techniques and discuss some related open problems.

  12. A Storage Assignment Model for Batch Preparation in Process Industries

    NARCIS (Netherlands)

    Ashayeri, J.; Selen, W.

    2010-01-01

    A new model formulation is developed for reducing the workload in pre-batching at a manufacturer of flavours and fragrances, by optimally assigning ingredients to different storage types, taking into account past usage of ingredients and several restrictions about volumes and number of storage units

  13. Perancangan Sistem Pengaduk Pada Bioreaktor Batch Untuk Meningkatkan Produksi Biogas

    OpenAIRE

    Candrika Widiartanti Yuwono; Totok Soehartanto

    2013-01-01

    Proses anaerob merupakan proses fermentasi dimana memiliki proses yang berlangsung cukup lama. Dan pada bioreaktor anaerob sistem batch, diduga terdapat indikasi pada penurunan jumlah produksi biogas, yang disebabkan karena tejadi pengendapan atau pemisahan antara limbah cair dengan padatannya. Untuk itu muncul upaya untuk melakukan sistem pengadukan agar terjadi homogenitas dan bisa menyerupai seperti kondisi awal, sehingga diharapkan dapat memperpanjang masa produksi biogas. Adapun pengaduk...

  14. On the track of fish batches in three distribution networks

    DEFF Research Database (Denmark)

    Randrup, Maria; Wu, Haiping; Jørgensen, Bo M.

    2012-01-01

    Three fish products sampled in retail shops were traced back to their origin and fish from the same batch were tracked forward towards the retailer, thereby simulating a recall situation. The resulting distribution networks were very complex, but to the extent that companies were willing to provide...

  15. Research of an Efficient Variant of Batch RSA Algorithm%一种有效的Batch RSA算法的研究

    Institute of Scientific and Technical Information of China (English)

    李云飞; 柳青; 李彤; 郝林

    2011-01-01

    提出了一种改进的Batch RSA算法来提升Batch RSA算法的解密性能.该改进算法结合了负载转移技术和Multi-Power RSA技术,在Batch RSA算法的指数计算阶段提升Batch RSA算法的解密性能.实验结果和理论分析表明,该改进算法使得Batch RSA算法的解密性能得到显著提升,且易于并行实现,可使基于多核平台的Batch RSA算法的整体性能得到进一步提升.%This paper aimed at speeding up Batch RSA decryption. An efficient variant of Batch RSA was proposed to improve the Batch RSA decryption performance. The improved Batch RSA variant speeds up decryption by combining the load transferring technique and multi-power RSA technique in the exponentiation phase. The experimental result and the theoretical values show that the speed of the decryption is substantially improved and the variant can be efficiently implemented in parallel and parallel implementation of the variant on multi-core devices can further improve the overall performance of Batch RSA algorithm.

  16. Computer Simulation of Batch Grinding Process Based on Simulink 5.0

    Institute of Scientific and Technical Information of China (English)

    LI Xia; YANG Ying-jie; DENG Hui-yong; HUANG Guang-yao

    2005-01-01

    How to use Simulink software in grinding system was studied. The method of designing batch grinding subsystem and the steps of building batch grinding blockset were introduced. Based on batch grinding population balance model, batch grinding was simulated with Simulink. The results show that the simulation system designed with Simulink explain reasonably the impersonal rule of batch grinding. On the basis of batch grinding simulation, the computer simulation of mineral processing system with Simulink of grinding and classification, comminution, etc, can be properly explored.

  17. Community dynamics of complex starter cultures for Gouda-type cheeses and its functional consequences

    NARCIS (Netherlands)

    Erkus, O.

    2014-01-01

    Lactic acid bacteria (LAB) are used as starter and adjunct cultures for the production of artisanal and industrial fermented milk products such as yoghurt and cheese.  Artisanal fermentations is propagated with the transfer of an inoculum from old batch of fermented food to the new batch (back-

  18. Glucoamylase production in batch, chemostat and fed-batch cultivations by an industrial strain of Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Beyer, Michael; Nielsen, Jens

    2000-01-01

    The Aspergillus niger strain BO-1 was grown in batch, continuous (chemostat) and fed-batch cultivations in order to study the production of the extracellular enzyme glucoamylase under different growth conditions. In the pH range 2.5-6.0, the specific glucoamylase productivity and the specific...... growth rate of the fungus were independent of pH when grown in batch cultivations. The specific glucoamylase productivity increased linearly with the specific growth rate in the range 0-0.1 h(-1) and was constant in the range 0.1-0.2 h(-1) Maltose and maltodextrin were non-inducing carbon sources...... compared to glucose, and the maximum specific growth rate was 0.19 +/- 0.02 h(-1) irrespective of whether glucose or maltose was the carbon source. In fed-batch cultivations, glucoamylase titres of up to 6.5 g 1(-1) were obtained even though the strain contained only one copy of the glaA gene....

  19. Fatty acid accumulation in the yeast Sporidiobolus salmonicolor during batch production of gamma-decalactone.

    Science.gov (United States)

    Feron, G; Dufossé, L; Mauvais, G; Bonnarme, P; Spinnler, H E

    1997-04-01

    This paper provides new information about the metabolism of various fatty acids and gamma-decalactone production by yeast. An analysis of the fatty acid composition of the yeast Sporidiobolus salmonicolor during batch production of lactone with ricinoleic acid methyl ester as a precursor showed an accumulation of the gamma-decalactone precursor inside the cells. Electron microscopy of the yeasts showed the presence of large internal inclusions leading to membrane and organelle lysis and, consequently, death of the yeast. S. salmonicolor cultivated with methyl oleate did not produce gamma-decalactone and is viable during the whole culture. Analysis of the long chain fatty acid fraction showed incorporation of methyl oleate. PMID:9103973

  20. Pulsed feeding during fed-batch Aspergillus oryzae fermentation leads to improved oxygen mass transfer.

    Science.gov (United States)

    Bhargava, Swapnil; Wenger, Kevin S; Marten, Mark R

    2003-01-01

    Productivity in many fungal fermentations is detrimentally affected by high broth viscosity and consequent reduced oxygen mass transfer capacity. The goal here was to determine whether pulsed feeding of limiting carbon in a fungal fermentation could lead to reduced viscosity and improved oxygen mass transfer. As a model, an industrially relevant recombinant strain of Aspergillus oryzae was grown in carbon-limited, fed-batch mode. Maltodextrin was used as a carbon source and was added either continuously or in 1.5-min pulses, 3.5 min apart. In both feeding modes the same total amount of carbon was added, and carbon feed rate was at sufficiently low levels to ensure cultures were always carbon-limited. Compared to continuous feeding, pulsed addition of substrate led to smaller fungal elements, which resulted in a significant reduction in broth viscosity. This in turn led to higher dissolved oxygen concentrations and increased oxygen uptake rates during pulsed feeding. PMID:12790687

  1. Photosynthetic bacteria production from food processing wastewater in sequencing batch and membrane photo-bioreactors.

    Science.gov (United States)

    Chitapornpan, S; Chiemchaisri, C; Chiemchaisri, W; Honda, R; Yamamoto, K

    2012-01-01

    Application of photosynthetic process could be highly efficient and surpass anaerobic treatment in releasing less greenhouse gas and odor while the biomass produced can be utilized. The combination of photosynthetic process with membrane separation is possibly effective for water reclamation and biomass production. In this study, cultivation of mixed culture photosynthetic bacteria from food processing wastewater was investigated in a sequencing batch reactor (SBR) and a membrane bioreactor (MBR) supplied with infrared light. Both photo-bioreactors were operated at a hydraulic retention time (HRT) of 10 days. Higher MLSS concentration achieved in the MBR through complete retention of biomass resulted in a slightly improved performance. When the system was operated with MLSS controlled by occasional sludge withdrawal, total biomass production of MBR and SBR photo-bioreactor was almost equal. However, 64.5% of total biomass production was washed out with the effluent in SBR system. Consequently, the higher biomass could be recovered for utilization in MBR. PMID:22258682

  2. Improved methane production from brown algae under high salinity by fed-batch acclimation.

    Science.gov (United States)

    Miura, Toyokazu; Kita, Akihisa; Okamura, Yoshiko; Aki, Tsunehiro; Matsumura, Yukihiko; Tajima, Takahisa; Kato, Junichi; Nakashimada, Yutaka

    2015-01-01

    Here, a methanogenic microbial community was developed from marine sediments to have improved methane productivity from brown algae under high salinity. Fed-batch cultivation was conducted by adding dry seaweed at 1wt% total solid (TS) based on the liquid weight of the NaCl-containing sediment per round of cultivation. The methane production rate and level of salinity increased 8-fold and 1.6-fold, respectively, at the 10th round of cultivation. Moreover, the rate of methane production remained high, even at the 10th round of cultivation, with accumulation of salts derived from 10wt% TS of seaweed. The salinity of the 10th-round culture was equivalent to 5% NaCl. The improved methane production was attributed to enhanced acetoclastic methanogenesis because acetate became rapidly converted to methane during cultivation. The family Fusobacteriaceae and the genus Methanosaeta, the acetoclastic methanogen, predominated in bacteria and archaea, respectively, after the cultivation.

  3. Batch conversion of methane to methanol using Methylosinus trichosporium OB3b as biocatalyst.

    Science.gov (United States)

    Hwang, In Yeub; Hur, Dong Hoon; Lee, Jae Hoon; Park, Chang-Ho; Chang, In Seop; Lee, Jin Won; Lee, Eun Yeol

    2015-03-01

    Recently, methane has attracted much attention as an alternative carbon feedstock since it is the major component of abundant shale and natural gas. In this work, we produced methanol from methane using whole cells of Methylosinus trichosporium OB3b as the biocatalyst. M. trichosporium OB3b was cultured on NMS medium with a supply of 7:3 air/methane ratio at 30°C. The optimal concentrations of various methanol dehydrogenase inhibitors such as potassium phosphate and EDTA were determined to be 100 and 0.5 mM, respectively, for an efficient production of methanol. Sodium formate (40 mM) as a reducing power source was added to enhance the conversion efficiency. A productivity of 49.0 mg/l·h, titer of 0.393 g methanol/l, and conversion of 73.8% (mol methanol/mol methane) were obtained under the optimized batch condition. PMID:25563419

  4. Effect of pH Heterogeneity in Large-scale Bioreactor on Fed-batch Culture Process of CHO cells%大型反应器内pH不均一性对CHO细胞流加培养过程的影响

    Institute of Scientific and Technical Information of China (English)

    刘金涛; 王星懿; 范里; 邓献存; 刘旭平; 谭文松

    2015-01-01

    In order to study the effect of pH heterogeneity in large-scale bioreactor on cell culture process of CHO cells, we established a scale down model consistent of stirred tank reactor and plug flow reactor to simulate the pH heterogeneity of large-scale bioreactor based on the mixing characteristic. The results showed that the scale down process with 30 s residence time has no statically difference with the control process. However, significant effect on cell growth, cell metabolism and protein production were found when increased the residence time of PFR. Cell growth rate decreased accompanied by tremendously increase of ammonia and lactate when increased the pH heterogeneity. In addition, the titer, sialic acid content and bioactivity of antibody fusion protein were also decreased when increased the pH heterogeneity.%为了研究大型反应器中pH不均一性对CHO细胞流加培养过程的影响,并将培养过程顺利地放大到生产规模,根据大型反应器的混合特性,构建了搅拌式反应器与平推流反应器串联的规模缩小装置用于模拟大型反应器中的pH不均一性。结果表明停留时间为30 s时,整个培养过程和对照相比并无显著的差异,这表明此时补碱所导致的pH不均一性并未对流加培养工艺造成影响。而随着停留时间的延长,反应器内pH不均一的程度越大,细胞生长和产物表达受到抑制越明显;与此同时,乳酸和氨的累积显著增加,而关键质量属性唾液酸和生物学活性也随之降低。

  5. A method of batch-purifying microalgae with multiple antibiotics at extremely high concentrations

    Science.gov (United States)

    Han, Jichang; Wang, Song; Zhang, Lin; Yang, Guanpin; Zhao, Lu; Pan, Kehou

    2016-01-01

    Axenic microalgal strains are highly valued in diverse microalgal studies and applications. Antibiotics, alone or in combination, are often used to avoid bacterial contamination during microalgal isolation and culture. In our preliminary trials, we found that many microalgae ceased growing in antibiotics at extremely high concentrations but could resume growth quickly when returned to an antibiotics-free liquid medium and formed colonies when spread on a solid medium. We developed a simple and highly efficient method of obtaining axenic microalgal cultures based on this observation. First, microalgal strains of different species or strains were treated with a mixture of ampicillin, gentamycin sulfate, kanamycin, neomycin and streptomycin (each at a concentration of 600 mg/L) for 3 days; they were then transferred to antibiotics-free medium for 5 days; and finally they were spread on solid f/2 media to allow algal colonies to form. With this method, five strains of Nannochloropsis sp. (Eustigmatophyceae), two strains of Cylindrotheca sp. (Bacillariophyceae), two strains of Tetraselmis sp. (Chlorodendrophyceae) and one strain of Amphikrikos sp. (Trebouxiophyceae) were purified successfully. The method shows promise for batch-purifying microalgal cultures.

  6. On the choice of batch mode in order to maximize throughput

    NARCIS (Netherlands)

    Weeda, P.J.

    1990-01-01

    An analysis of serial process configurations consisting of three processes and two machines shows interesting relations between the choice of batch mode (or batch structure), utilization of capacities and maximum throughput.

  7. JAVA Implementation of the Batched iLab Shared Architecture

    Directory of Open Access Journals (Sweden)

    Lenard Payne

    2013-04-01

    Full Text Available The MIT iLab Shared Architecture is limited currently to running on the Microsoft Windows platform. A JAVA implementation of the Batched iLab Shared Architecture has been developed that can be used on other operating systems and still interoperate with the existing Microsoft .NET web services of MIT’s iLab ServiceBroker. The Batched iLab Shared Architecture has been revised and separates the Labserver into a LabServer that handles experiment management and a LabEquipment that handles experiment execution. The JAVA implementation provides a 3-tier code development model that allows code to be reused and to develop only the code that is specific to each experiment.

  8. Nonlinear dynamic modeling of multicomponent batch distillation: a case study

    Directory of Open Access Journals (Sweden)

    L. Jiménez

    2002-07-01

    Full Text Available The aim of this work is to compare several of the commercial dynamic models for batch distillation available worldwide. In this context, BATCHFRAC™, CHEMCAD™ BATCH, and HYSYS.Plant® software performances are compared to experimental data. The software can be used as soft sensors, playing the roll of ad-hoc observers or estimators for control objectives. Rigorous models were used as an alternative to predict the concentration profile and to specify the optimal switching time from products to slop cuts. The performance of a nonlinear model obtained using a novel identification algorithm was also studied. In addition, the strategy for continuous separation was revised with residue curve map analysis using Aspen SPLIT™.

  9. Method to incorporate energy integration considerations in multiproduct batch processes

    Energy Technology Data Exchange (ETDEWEB)

    Corominas, J.; Espuna, A.; Puigjaner, L. (Universidad Politecnica de Cataluna, Barcelona (Spain))

    Systemization of an energy saving grass-root design and retrofitting technology based on process integration is a subject of increasing interest in plants running under the batch mode of operation. In this work, the solution to the product changeover problem is studied in order to achieve a feasible and optimized heat exchange network design for multiproduct batch plants. A new methodology is presented which is based on: (a) the campaign-mode of plant operation; and (b) the study of energy integration for each campaign. The concept of Macronetwork is also introduced. Algorithms to obtain the best feasible matches and energy targets are presented and results of test-case studies are discussed to illustrate this methodology. (author)

  10. A new look at energy integration in multiproduct batch processes

    Energy Technology Data Exchange (ETDEWEB)

    Corominas, J.; Espuna, A.; Puigjaner, L. (Univ. Politecnica de Catalunya (Spain). Chemical Engineering Dept.)

    1993-01-01

    Systematization of an energy saving grass-root design and retrofitting technology based on process integration is a subject of increasing interest in plants running under the batch mode of operation. In this work, the solution to the changeover product problem is studied in order to achieve a feasible and optimized heat exchange network design for multiproduct batch plants. A new methodology is presented which is based on: (a) the campaign-mode of plant operation, (b) the study of energy integration for each campaign. The concept of Macronetwork is also introduced. This includes the heat exchanger network of all campaigns in an overall design, and contemplates the common matches between networks of campaigns of different products. Algorithms to obtain the best feasible matches and energy targets are presented and results of test-case studies are discussed to illustrate this methodology. (author)

  11. Sorting Olive Batches for the Milling Process Using Image Processing

    Directory of Open Access Journals (Sweden)

    Daniel Aguilera Puerto

    2015-07-01

    Full Text Available The quality of virgin olive oil obtained in the milling process is directly bound to the characteristics of the olives. Hence, the correct classification of the different incoming olive batches is crucial to reach the maximum quality of the oil. The aim of this work is to provide an automatic inspection system, based on computer vision, and to classify automatically different batches of olives entering the milling process. The classification is based on the differentiation between ground and tree olives. For this purpose, three different species have been studied (Picudo, Picual and Hojiblanco. The samples have been obtained by picking the olives directly from the tree or from the ground. The feature vector of the samples has been obtained on the basis of the olive image histograms. Moreover, different image preprocessing has been employed, and two classification techniques have been used: these are discriminant analysis and neural networks. The proposed methodology has been validated successfully, obtaining good classification results.

  12. Screening and assessment of performance and molecule quality attributes of industrial cell lines across different fed-batch systems.

    Science.gov (United States)

    Rouiller, Yolande; Bielser, Jean-Marc; Brühlmann, David; Jordan, Martin; Broly, Hervé; Stettler, Matthieu

    2016-01-01

    The major challenge in the selection process of recombinant cell lines for the production of biologics is the choice, early in development, of a clonal cell line presenting a high productivity and optimal cell growth. Most importantly, the selected candidate needs to generate a product quality profile which is adequate with respect to safety and efficacy and which is preserved across cell culture scales. We developed a high-throughput screening and selection strategy of recombinant cell lines, based on their productivity in shaking 96-deepwell plates operated in fed-batch mode, which enables the identification of cell lines maintaining their high productivity at larger scales. Twelve recombinant cell lines expressing the same antibody with different productivities were selected out of 470 clonal cell lines in 96-deepwell plate fed-batch culture. They were tested under the same conditions in 50 mL vented shake tubes, microscale and lab-scale bioreactors in order to confirm the maintenance of their performance at larger scales. The use of a feeding protocol and culture conditions which are essentially the same across the different scales was essential to maintain productivity and product quality profiles across scales. Compared to currently used approaches, this strategy has the advantage of speeding up the selection process and increases the number of screened clones for getting high-producing recombinant cell lines at manufacturing scale with the desired performance and quality.

  13. MACROSCOPIC KINETIC MODELS OF GLYCEROL BATCH FERMENTATION WITH OSMOTOLERANT YEAST

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    l introductionGlycerol production by fermentation has beenwidely investigated to meet the great commercialdemand in last decades and osmotolerant yeast wasthe microorganism studied most. To analyze thefermentation process more efficiently, a kinetic modelshould be established but little works about it werereported because of its complicated metabolism ofglycerol [1-3]. Batch fermentation experiment showedthat low glucose concentration in the latterfermentation stage resulted in decrease in both glucoseconsu...

  14. Batch gating for data association in monocular SLAM

    OpenAIRE

    Guerra Paradas, Edmundo; Munguía Alcalá, Rodrigo Francisco; Bolea Monte, Yolanda; Grau Saldes, Antoni

    2013-01-01

    This work describes the development and implementation of a single-camera SLAM system, introducing a novel data validation algorithm. A 6-DOF monocular SLAM method developed is based on the Delayed Inverse-Depth (DI-D) Feature Initialization, with the addition of a new data association batch validation technique, the Highest Order Hypothesis Compatibility Test, HOHCT. The DI-D initializes new features in the system defining single hypothesis for the initial depth of features by stoch...

  15. Group technology. [Increasing batch-lot production efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Rome, C.P.

    1976-01-01

    Group Technology has been conceptually applied to the manufacture of batch-lots of 554 machined electromechanical parts which now require 79 different types of metal-removal tools. The products have been grouped into 7 distinct families which require from 8 to 22 machines in each machine-cell. Throughput time can be significantly reduced and savings can be realized from tooling, direct-labor, and indirect-labor costs.

  16. Feasibility of extractive distillation process variants in batch rectifier column

    OpenAIRE

    Stéger, Csaba; Varga, Viktoria; Horvath, Laszlo; Rev, Endre; Fonyo, Zsolt; Meyer, Michel; Lelkes, Zoltan

    2005-01-01

    A systematic comparison is presented about the separation tasks of azeotropic and close-boiling mixtures applying batch extractive distillation (BED) in rectifier. All the eight possible mixture types with at most a single azeotrope (minimum and maximum boiling azeotropes with heavy, light, and intermediate boiling entrainers; and close boiling mixtures with heavy and light entrainers) are compared. The main results of the feasibility studies on the hitherto unpublished cases are presented. A...

  17. Mathematical modeling of recombinant Escherichia coli aerobic batch fermentations

    OpenAIRE

    Costa, Rafael S; Rocha, I; Ferreira, E. C.

    2008-01-01

    In this work, three competing unstructured mathematical models for the biomass growth by recombinant E. coli strains with different acetate inhibition kinetics terms were evaluated for batch processes at constant temperature and pH. The models considered the dynamics of biomass growth, acetate accumulation, substrate consumption, Green Fluorescence Protein (GFP) production and three metabolic pathways for E. coli. Parameter estimation and model validation was carried out usi...

  18. EFFECT OF DYE CONCENTRATION ON SEQUENCING BATCH REACTOR PERFORMANCE

    OpenAIRE

    A. A. Vaigan ، M. R. Alavi Moghaddam ، H. Hashemi

    2009-01-01

    Reactive dyes have been identified as problematic compounds in textile industries wastewater as they are water soluble and cannot be easily removed by conventional aerobic biological treatment systems. The treatability of a reactive dye (Brill Blue KN-R) by sequencing batch reactor and the influence of the dye concentration on system performance were investigated in this study. Brill Blue KN-R is one of the main dyes that are used in textile industries in Iran. Four cylindrical Plexiglas reac...

  19. Optimization of Recipe Based Batch Control Systems Using Neural Networks

    OpenAIRE

    Šoštarec, A.; Gosak, D.; Hlupić, N.

    2012-01-01

    In the modern pharmaceutical industry many flexible batch plants operate under an integrated business and production system, using ISA S95 and ISA S88 standards for models and terminology, and implementing flexible recipe-based production. In the environment of constantly changing market conditions, adjustment to surroundings is a business necessity. To support necessary production improvement, regulatory authorities have introduced the risk based approach for the control of process dev...

  20. Industrial and Municipal Wastewater Treatment in the Sequencing Batch Reactor

    OpenAIRE

    Vrtovsek, J.; Ros, M.

    2008-01-01

    A mixture of Industrial wastewater from chemical industry (varnish, paint and pigments production) and municipal wastewater was treated in pilot sequencing batch reactor (SBR). Results of the pilot experiments show that the foaming problem has great influence on the behavior of SBR, especially when the ratio between industrial and municipal wastewater is very high. Foaming problem was negligible when the mixture with φ; 20 % of the industrial wastewater and j = 80 % of the municipal wastewate...

  1. SEQUENCING BATCH REACTOR: A PROMISING TECHNOLOGY IN WASTEWATER TREATMENT

    OpenAIRE

    A.H Mahvi

    2008-01-01

    Discharge of domestic and industrial wastewater to surface or groundwater is very dangerous to the environment. Therefore treatment of any kind of wastewater to produce effluent with good quality is necessary. In this regard choosing an effective treatment system is important. Sequencing batch reactor is a modification of activated sludge process which has been successfully used to treat municipal and industrial wastewater. The process could be applied for nutrients removal, high biochemical ...

  2. Integration of virtualized worker nodes in standard batch systems

    Energy Technology Data Exchange (ETDEWEB)

    Buege, Volker; Kunze, Marcel; Oberst, Oliver; Quast, Guenter; Scheurer, Armin [Karlsruhe Institute of Technology, Postfach 6980, 76128 Karlsruhe (Germany); Hessling, Hermann [HTW Berlin, University of Applied Sciences, 10318 Berlin (Germany); Kemp, Yves; Synge, Owen, E-mail: Oliver.Oberst@iwr.fzk.d [DESY, Notkestrasse 85, 22607 Hamburg (Germany)

    2010-04-01

    Current experiments in HEP only use a limited number of operating system flavours. Their software might only be validated on one single OS platform. Resource providers might have other operating systems of choice for the installation of the batch infrastructure. This is especially the case if a cluster is shared with other communities, or communities that have stricter security requirements. One solution would be to statically divide the cluster into separated sub-clusters. In such a scenario, no opportunistic distribution of the load can be achieved, resulting in a poor overall utilization efficiency. Another approach is to make the batch system aware of virtualization, and to provide each community with its favoured operating system in a virtual machine. Here, the scheduler has full flexibility, resulting in a better overall efficiency of the resources. In our contribution, we present a lightweight concept for the integration of virtual worker nodes into standard batch systems. The virtual machines are started on the worker nodes just before jobs are executed there. No meta-scheduling is introduced. We demonstrate two prototype implementations, one based on the Sun Grid Engine (SGE), the other using Maui/Torque as a batch system. Both solutions support local job as well as Grid job submission. The hypervisors currently used are Xen and KVM, a port to another system is easily envisageable. To better handle different virtual machines on the physical host, the management solution VmImageManager is developed. We will present first experience from running the two prototype implementations. In a last part, we will show the potential future use of this lightweight concept when integrated into high-level (i.e. Grid) work-flows.

  3. Health advantages of transition to batch management system in farrow-to-finish pig herds

    OpenAIRE

    Vangroenweghe, F; Suls, L; Van Driessche, E.; Maes, Dominiek; De Graef, E.

    2012-01-01

    Sow batch management systems have become more popular due to advantages in labour planning, piglet batch sizes, all-in all-out practices and health management. The present study investigated the potential health advantages of 10 selected farrow-to-finish pig herds before and after transition from a one week batch management system to a four or five week batch management system. Five different animal categories (gilts, sows, piglets, growers and finishers) were sampled at three time points (T0...

  4. On-line Scheduling Algorithm for Penicillin Fed-batch Fermentation

    Institute of Scientific and Technical Information of China (English)

    XUE Yao-feng; YUAN Jing-qi

    2005-01-01

    An on-line scheduling algorithm to maximize gross profit of penicillin fed-batch fermentation is proposed. According to the on-line classification method, fed-batch fermentation batches are classified into three categories. Using the scheduling strategy, the optimal termination sequence of batches is obtained. Pseudo on-line simulations for testing the proposed algorithm with the data from industrial scale penicillin fermentation are carried out.

  5. Analyzing data flows of WLCG jobs at batch job level

    Science.gov (United States)

    Kuehn, Eileen; Fischer, Max; Giffels, Manuel; Jung, Christopher; Petzold, Andreas

    2015-05-01

    With the introduction of federated data access to the workflows of WLCG, it is becoming increasingly important for data centers to understand specific data flows regarding storage element accesses, firewall configurations, as well as the scheduling of batch jobs themselves. As existing batch system monitoring and related system monitoring tools do not support measurements at batch job level, a new tool has been developed and put into operation at the GridKa Tier 1 center for monitoring continuous data streams and characteristics of WLCG jobs and pilots. Long term measurements and data collection are in progress. These measurements already have been proven to be useful analyzing misbehaviors and various issues. Therefore we aim for an automated, realtime approach for anomaly detection. As a requirement, prototypes for standard workflows have to be examined. Based on measurements of several months, different features of HEP jobs are evaluated regarding their effectiveness for data mining approaches to identify these common workflows. The paper will introduce the actual measurement approach and statistics as well as the general concept and first results classifying different HEP job workflows derived from the measurements at GridKa.

  6. Batch fabrication of micro-optical sensing and imaging devices

    Science.gov (United States)

    Wippermann, F. C.; Reimann, A.; Oelschläger, A.; Dannberg, P.; Blöhbaum, F.; Koburg, C.; Köhler, T.

    2013-03-01

    As demonstrated in microelectronics, the batch fabrication based on the processing of wafers can lead to a significant reduction in prize as well as in size. This concept was adapted to the fabrication of imaging optics extensively used in mobile phone cameras relying on small pixels and low resolutions such as VGA. We report on batch fabricated customer specific opto-electronical modules used in machine sensing and automotive applications relying on large pixel sizes and non-conventional sensor characteristics. We specially focus on the lens mold mastering for the subsequent UV-replication since comparatively large sag heights of 250μm are required. Two technological approaches were applied, first, based on reflow of photoresist and, second, using diamond turning for the generation of a single lens mold and a subsequent step&repeat-process for array mastering on 8" wafers. Aspects of the optical design and simulation, the batch fabrication based on 8" wafers and characterization results are provided by the example of an f/1.1 opto-electronic sensor and an objective for a global shutter imager using 550x550 pixels with 3.6μm pitch.

  7. Fault Diagnosis of Batch Reactor Using Machine Learning Methods

    Directory of Open Access Journals (Sweden)

    Sujatha Subramanian

    2014-01-01

    Full Text Available Fault diagnosis of a batch reactor gives the early detection of fault and minimizes the risk of thermal runaway. It provides superior performance and helps to improve safety and consistency. It has become more vital in this technical era. In this paper, support vector machine (SVM is used to estimate the heat release (Qr of the batch reactor both normal and faulty conditions. The signature of the residual, which is obtained from the difference between nominal and estimated faulty Qr values, characterizes the different natures of faults occurring in the batch reactor. Appropriate statistical and geometric features are extracted from the residual signature and the total numbers of features are reduced using SVM attribute selection filter and principle component analysis (PCA techniques. artificial neural network (ANN classifiers like multilayer perceptron (MLP, radial basis function (RBF, and Bayes net are used to classify the different types of faults from the reduced features. It is observed from the result of the comparative study that the proposed method for fault diagnosis with limited number of features extracted from only one estimated parameter (Qr shows that it is more efficient and fast for diagnosing the typical faults.

  8. Perancangan Sistem Pengaduk Pada Bioreaktor Batch Untuk Meningkatkan Produksi Biogas

    Directory of Open Access Journals (Sweden)

    Candrika Widiartanti Yuwono

    2013-03-01

    Full Text Available Proses anaerob merupakan proses fermentasi dimana memiliki proses yang berlangsung cukup lama. Dan pada bioreaktor anaerob sistem batch, diduga terdapat indikasi pada penurunan jumlah produksi biogas, yang disebabkan karena tejadi pengendapan atau pemisahan antara limbah cair dengan padatannya. Untuk itu muncul upaya untuk melakukan sistem pengadukan agar terjadi homogenitas dan bisa menyerupai seperti kondisi awal, sehingga diharapkan dapat memperpanjang masa produksi biogas. Adapun pengadukan merupakan salah satu faktor yang berpengaruh pada kehidupan mikroba. Dan pada penelitian ini akan dilakukan perancangan sistem pengaduk yang digerakkan oleh sebuah motor dimana menggunakan timer dan pengatur kecepatan. Desain disesuaikan dengan substrat yang digunakan yaitu limbah cair tahu dan eceng gondok, yang mengalami pengendapan sehingga pada pengaduk memiliki blade yang diletakkan di dasar dalam bioreaktor. Sistem pengadukan dilakukan pada saat nilai pH yang diamati tiap harinya mengalami penurunan, yaitu pada hari ke–24 pH bernilai 6,49. Dan pada pengukuran berikutnya ditunjukkan dengan pH bernilai 6,89. Pengadukan dilakukan secara pelan dengan putaran 170 rpm selama 2 x 1 menit. Hasil daripada jumlah produksi biogas yang dihasilkan bisa dibandingkan antara bioreaktor batch tidak berpengaduk dengan bioreaktor batch berpengaduk, dimana berturut-turut memiliki jumlah volume 467 mL (25 hari dan 873 mL (31 hari.

  9. 40 CFR Table 2 to Subpart Vvvvvv... - Emission Limits and Compliance Requirements for Batch Process Vents

    Science.gov (United States)

    2010-07-01

    ... Requirements for Batch Process Vents 2 Table 2 to Subpart VVVVVV of Part 63 Protection of Environment... of Part 63—Emission Limits and Compliance Requirements for Batch Process Vents As required in § 63.11496, you must comply with the requirements for batch process vents as shown in the following...

  10. A General framework for the Synthesis and Operational Design of Batch Processes

    DEFF Research Database (Denmark)

    The objective of this paper is to present a general problem formulation and a general methodlogy for the synthesis of batch operations and the operational design of individual batch processes, such as mixing, reaction and separation. The general methodology described supplies the batch routes...

  11. A general framework for the synthesis and operational design of batch processes

    DEFF Research Database (Denmark)

    Papaeconomou, Eirini; Gani, Rafiqul; Jørgensen, Sten Bay

    2002-01-01

    The objective of this paper is to present a general problem formulation and a general methodology for the synthesis of batch operations and the operational design of individual batch processes, such as mixing, reaction and separation. The general methodology described supplies the batch routes...

  12. Look-ahead strategies for controlling batch operations in industry : basic insights in rule construction

    NARCIS (Netherlands)

    van der Zee, D.J.; Sullivan, W.A.; Ahmad, M.M.; Fichtner, D.; Sauer, W.; Weigert, G.; Zerna, T.

    2002-01-01

    Batching jobs in a manufacturing system is a very common policy in most industries. Main reasons for batching are avoidance of set ups and/or facilitation of material handling. Examples of batch-wise production systems are ovens found in aircraft industry and in semiconductor manufacturing. Starting

  13. OSAT: a tool for sample-to-batch allocations in genomics experiments

    Directory of Open Access Journals (Sweden)

    Yan Li

    2012-12-01

    Full Text Available Abstract Background Batch effect is one type of variability that is not of primary interest but ubiquitous in sizable genomic experiments. To minimize the impact of batch effects, an ideal experiment design should ensure the even distribution of biological groups and confounding factors across batches. However, due to the practical complications, the availability of the final collection of samples in genomics study might be unbalanced and incomplete, which, without appropriate attention in sample-to-batch allocation, could lead to drastic batch effects. Therefore, it is necessary to develop effective and handy tool to assign collected samples across batches in an appropriate way in order to minimize the impact of batch effects. Results We describe OSAT (Optimal Sample Assignment Tool, a bioconductor package designed for automated sample-to-batch allocations in genomics experiments. Conclusions OSAT is developed to facilitate the allocation of collected samples to different batches in genomics study. Through optimizing the even distribution of samples in groups of biological interest into different batches, it can reduce the confounding or correlation between batches and the biological variables of interest. It can also optimize the homogeneous distribution of confounding factors across batches. It can handle challenging instances where incomplete and unbalanced sample collections are involved as well as ideally balanced designs.

  14. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    OpenAIRE

    Gupta Rishi; Kumar Sanjay; Gomes James; Kuhad Ramesh

    2012-01-01

    Abstract Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydroly...

  15. Application of simple fed-batch technique to high-level secretory production of insulin precursor using Pichia pastoris with subsequent purification and conversion to human insulin

    Science.gov (United States)

    2010-01-01

    Background The prevalence of diabetes is predicted to rise significantly in the coming decades. A recent analysis projects that by the year 2030 there will be ~366 million diabetics around the world, leading to an increased demand for inexpensive insulin to make this life-saving drug also affordable for resource poor countries. Results A synthetic insulin precursor (IP)-encoding gene, codon-optimized for expression in P. pastoris, was cloned in frame with the Saccharomyces cerevisiae α-factor secretory signal and integrated into the genome of P. pastoris strain X-33. The strain was grown to high-cell density in a batch procedure using a defined medium with low salt and high glycerol concentrations. Following batch growth, production of IP was carried out at methanol concentrations of 2 g L-1, which were kept constant throughout the remaining production phase. This robust feeding strategy led to the secretion of ~3 gram IP per liter of culture broth (corresponding to almost 4 gram IP per liter of cell-free culture supernatant). Using immobilized metal ion affinity chromatography (IMAC) as a novel approach for IP purification, 95% of the secreted product was recovered with a purity of 96% from the clarified culture supernatant. Finally, the purified IP was trypsin digested, transpeptidated, deprotected and further purified leading to ~1.5 g of 99% pure recombinant human insulin per liter of culture broth. Conclusions A simple two-phase cultivation process composed of a glycerol batch and a constant methanol fed-batch phase recently developed for the intracellular production of the Hepatitis B surface antigen was adapted to secretory IP production. Compared to the highest previously reported value, this approach resulted in an ~2 fold enhancement of IP production using Pichia based expression systems, thus significantly increasing the efficiency of insulin manufacture. PMID:20462406

  16. Application of simple fed-batch technique to high-level secretory production of insulin precursor using Pichia pastoris with subsequent purification and conversion to human insulin

    Directory of Open Access Journals (Sweden)

    Chugh Dipti

    2010-05-01

    Full Text Available Abstract Background The prevalence of diabetes is predicted to rise significantly in the coming decades. A recent analysis projects that by the year 2030 there will be ~366 million diabetics around the world, leading to an increased demand for inexpensive insulin to make this life-saving drug also affordable for resource poor countries. Results A synthetic insulin precursor (IP-encoding gene, codon-optimized for expression in P. pastoris, was cloned in frame with the Saccharomyces cerevisiae α-factor secretory signal and integrated into the genome of P. pastoris strain X-33. The strain was grown to high-cell density in a batch procedure using a defined medium with low salt and high glycerol concentrations. Following batch growth, production of IP was carried out at methanol concentrations of 2 g L-1, which were kept constant throughout the remaining production phase. This robust feeding strategy led to the secretion of ~3 gram IP per liter of culture broth (corresponding to almost 4 gram IP per liter of cell-free culture supernatant. Using immobilized metal ion affinity chromatography (IMAC as a novel approach for IP purification, 95% of the secreted product was recovered with a purity of 96% from the clarified culture supernatant. Finally, the purified IP was trypsin digested, transpeptidated, deprotected and further purified leading to ~1.5 g of 99% pure recombinant human insulin per liter of culture broth. Conclusions A simple two-phase cultivation process composed of a glycerol batch and a constant methanol fed-batch phase recently developed for the intracellular production of the Hepatitis B surface antigen was adapted to secretory IP production. Compared to the highest previously reported value, this approach resulted in an ~2 fold enhancement of IP production using Pichia based expression systems, thus significantly increasing the efficiency of insulin manufacture.

  17. Production of gamma-aminobutyric acid by Lactobacillus brevis NCL912 using fed-batch fermentation

    Directory of Open Access Journals (Sweden)

    Huang Guidong

    2010-11-01

    Full Text Available Abstract Background Gamma-aminobutyric acid is a major inhibitory neurotransmitter in mammalian brains, and has several well-known physiological functions. Lactic acid bacteria possess special physiological activities and are generally regarded as safe. Therefore, using lactic acid bacteria as cell factories for gamma-aminobutyric acid production is a fascinating project and opens up a vast range of prospects for making use of GABA and LAB. We previously screened a high GABA-producer Lactobacillus brevis NCL912 and optimized its fermentation medium composition. The results indicated that the strain showed potential in large-scale fermentation for the production of gamma-aminobutyric acid. To increase the yielding of GABA, further study on the fermentation process is needed before the industrial application in the future. In this article we investigated the impacts of pyridoxal-5'-phosphate, pH, temperature and initial glutamate concentration on gamma-aminobutyric acid production by Lactobacillus brevis NCL912 in flask cultures. According to the data obtained in the above, a simple and effective fed-batch fermentation method was developed to highly efficiently convert glutamate to gamma-aminobutyric acid. Results Pyridoxal-5'-phosphate did not affect the cell growth and gamma-aminobutyric acid production of Lb. brevis NCL912. Temperature, pH and initial glutamate concentration had significant effects on the cell growth and gamma-aminobutyric acid production of Lb. brevis NCL912. The optimal temperature, pH and initial glutamate concentration were 30-35°C, 5.0 and 250-500 mM. In the following fed-batch fermentations, temperature, pH and initial glutamate concentration were fixed as 32°C, 5.0 and 400 mM. 280.70 g (1.5 mol and 224.56 g (1.2 mol glutamate were supplemented into the bioreactor at 12 h and 24 h, respectively. Under the selected fermentation conditions, gamma-aminobutyric acid was rapidly produced at the first 36 h and almost not

  18. Ethanol Production from Whey by Kluyveromyces marxianus in Batch Fermentation System: Kinetics Parameters Estimation

    Directory of Open Access Journals (Sweden)

    Dessy Ariyanti

    2013-03-01

    Full Text Available Whey is the liquid remaining after milk has been curdled and strained. It is a by-product of the manufacture of cheese or casein and has several commercial uses. In environmental point of view, whey is kind of waste which has high pollution level due to it’s contain high organic compound with BOD and COD value 50 and 80 g/L respectively. On the other side, whey also contain an amount of lactose (4.5%-5%; lactose can be used as carbon source and raw material for producing ethanol via fermentation using yeast strain Kluyveromyces marxianus. The objective of this research is to investigate the ethanol production kinetics from crude whey through fermentation using Kluyveromyces marxianus and to predict the model kinetics parameter. The yeast was able to metabolize most of the lactose within 16 h to give 8.64 g/L ethanol, 4.43 g/L biomass, and remain the 3.122 g/L residual lactose. From the results presented it also can be concluded that common kinetic model for microbial growth, substrate consumption, and product formation is a good alternative to describe an experimental batch fermentation of Kluyveromyces marxianus grown on a medium composed of whey. The model was found to be capable of reflecting all batch culture phases to a certain degree of accuracy, giving the parameter value: μmax, Ks, YX/S, α, β : 0.32, 10.52, 0.095, 1.52, and 0.11 respectively. © 2013 BCREC UNDIP. All rights reserved(Selected Paper from International Conference on Chemical and Material Engineering (ICCME 2012Received: 27th September 2012; Revised: 29th November 2012; Accepted: 7th December 2012[How to Cite: D. Ariyanti, H. Hadiyanto, (2013. Ethanol Production from Whey by Kluyveromyces marxianus in Batch Fermentation System: Kinetics Parameters Estimation. Bulletin of Chemical Reaction Engineering & Catalysis, 7 (3: 179-184. (doi:10.9767/bcrec.7.3.4044.179-184][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.7.3.4044.179-184 ] View in  |

  19. A design algorithm for batch stirred tank transesterification reactors

    International Nuclear Information System (INIS)

    Highlights: ► Simplified algorithm for batch biodiesel reactor design was developed. ► C Sharp software tool for implementing the algorithm was also developed. ► 50 L/batch reactor was constructed and used to process neem oil biodiesel. ► Results showed that the produced neem biodiesel is a fuel grade product. ► Scale-up of the reactor was carried out using the developed software. - Abstract: A 50 L per batch, stirred tank reactor, suitable for carrying out transesterification of vegetable oils was designed and constructed. The major design assumptions included stainless steel plate thickness of 2 mm, reaction temperature of 60–65 °C and an initial/final fluid temperature of 25/70 °C. The calculated impeller Reynolds number was in the mixed regime zone of 10–104; the power number was varied between 1 and 5, while a typical propeller speed of 22.5 rev/s (or 1350 rev/min) was adopted. The limiting design conditions were maximum reactor diameter of 1.80 m, straight side height-to-diameter ratio in the range of 0.75–1.5 and minimum agitator motor power of 746 W (1 Hp). Based upon the design, a simple algorithm was developed and interpreted into Microsoft C Sharp computer programming language to enable scale up of the reactor. Performance testing of the realized reactor was carried out while using it to produce Neem oil biodiesel via base – catalyzed methanolysis, which yielded high quality fuel product.

  20. Persistence of Escherichia coli in batch and continuous vermicomposting systems.

    Science.gov (United States)

    Hénault-Ethier, Louise; Martin, Vincent J J; Gélinas, Yves

    2016-10-01

    Vermicomposting is a biooxidation process in which epigeicearthworms act in synergy with microbial populations to degrade organic matter. Vermicomposting does not go through a thermophilic stage as required by North American legislations for pathogen eradication. We examined the survival of a Green Fluorescent Protein (GFP) labeled Escherichia coli MG1655 as a model for the survival of pathogenic bacteria in both small-scale batch and medium-scale continuously-operated systems to discern the influence of the earthworm Eisenia fetida, nutrient content and the indigenous vermicompost microbial community on pathogen abundance. In batch systems, the microbial community had the greatest influence on the rapid decline of E. coli populations, and the effect of earthworms was only visible in microbially-impoverishedvermicomposts. No significant earthworm density-dependent relationship was observed on E. coli survival under continuous operation. E. coli numbers decreased below the US EPA compost sanitation guidelines of 10(3)Colony Forming Units (CFU)/g (dry weight) within 18-21days for both the small-scale batch and medium-scale continuous systems, but it took up to 51days without earthworms and with an impoverished microbial community to reach the legal limit. Nutrient replenishment (i.e. organic carbon) provided by continuous feed input did not appear to extend E. coli survival. In fact, longer survival of E. coli was noticed in treatments where less total and labile sugars were available, suggesting that sugars may support potentially antagonist bacteria in the vermicompost. Total N, pH and humidity did not appear to affect E. coli survival. Several opportunistic human pathogens may be found in vermicompost, and their populations are likely kept in check by antagonists.

  1. Persistence of Escherichia coli in batch and continuous vermicomposting systems.

    Science.gov (United States)

    Hénault-Ethier, Louise; Martin, Vincent J J; Gélinas, Yves

    2016-10-01

    Vermicomposting is a biooxidation process in which epigeicearthworms act in synergy with microbial populations to degrade organic matter. Vermicomposting does not go through a thermophilic stage as required by North American legislations for pathogen eradication. We examined the survival of a Green Fluorescent Protein (GFP) labeled Escherichia coli MG1655 as a model for the survival of pathogenic bacteria in both small-scale batch and medium-scale continuously-operated systems to discern the influence of the earthworm Eisenia fetida, nutrient content and the indigenous vermicompost microbial community on pathogen abundance. In batch systems, the microbial community had the greatest influence on the rapid decline of E. coli populations, and the effect of earthworms was only visible in microbially-impoverishedvermicomposts. No significant earthworm density-dependent relationship was observed on E. coli survival under continuous operation. E. coli numbers decreased below the US EPA compost sanitation guidelines of 10(3)Colony Forming Units (CFU)/g (dry weight) within 18-21days for both the small-scale batch and medium-scale continuous systems, but it took up to 51days without earthworms and with an impoverished microbial community to reach the legal limit. Nutrient replenishment (i.e. organic carbon) provided by continuous feed input did not appear to extend E. coli survival. In fact, longer survival of E. coli was noticed in treatments where less total and labile sugars were available, suggesting that sugars may support potentially antagonist bacteria in the vermicompost. Total N, pH and humidity did not appear to affect E. coli survival. Several opportunistic human pathogens may be found in vermicompost, and their populations are likely kept in check by antagonists. PMID:27499290

  2. Kinetics and dynamic modelling of batch anaerobic digestion of municipal solid waste in a stirred reactor.

    Science.gov (United States)

    Nopharatana, Annop; Pullammanappallil, Pratap C; Clarke, William P

    2007-01-01

    A series of batch, slurry anaerobic digestion experiments were performed where the soluble and insoluble fractions, and unwashed MSW were separately digested in a 200l stirred stainless steel vessel at a pH of 7.2 and a temperature of 38 degrees C. It was found that 7% of the total MSW COD was readily soluble, of which 80% was converted to biogas; 50% of the insoluble fraction was solubilised, of this only 80% was converted to biogas. The rate of digesting the insoluble fraction was about four times slower than the rate of digesting the soluble fraction; 48% of the total COD was converted to biogas and 40% of the total nitrogen was converted to ammonia. Soluble and insoluble fractions were broken down simultaneously. The minimum time to convert 95% of the degradable fraction to biogas was 20 days. The lag phase for the degradation of insoluble fraction of MSW can be overcome by acclimatising the culture with the soluble fraction. The rate of digestion and the methane yield was not affected by particle size (within the range of 2-50mm). A dynamic model was developed to describe batch digestion of MSW. The parameters of the model were estimated using data from the separate digestion of soluble and insoluble fractions and validated against data from the digestion of unwashed MSW. Trends in the specific aceticlastic and formate-utilising methanogenic activity were used to estimate initial methanogenic biomass concentration and bacterial death rate coefficient. The kinetics of hydrolysis of insoluble fraction could be adequately described by a Contois equation and the kinetics of acidogenesis, and aceticlastic and hydrogen utilising methanogenesis by Monod equations. PMID:16797956

  3. REAL WASTE TESTING OF SLUDGE BATCH 5 MELTER FEED RHEOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    Reboul, S.; Stone, M.

    2010-03-17

    Clogging of the melter feed loop at the Defense Waste Processing Facility (DWPF) has reduced the throughput of Sludge Batch 5 (SB5) processing. After completing a data review, DWPF attributed the clogging to the rheological properties of the Slurry Mix Evaporator (SME) project. The yield stress of the SB5 melter feed material was expected to be high, based on the relatively high pH of the SME product and the rheological results of a previous Chemical Process Cell (CPC) demonstration performed at the Savannah River National Laboratory (SRNL).

  4. Simple multicomponent batch distillation procedure with a variable reflux policy

    Directory of Open Access Journals (Sweden)

    A. N. García

    2014-06-01

    Full Text Available This paper describes a shortcut procedure for batch distillation simulation with a variable reflux policy. The procedure starts from a shortcut method developed by Sundaram and Evans in 1993 and uses an iterative cycle to calculate the reflux ratio at each moment. The functional relationship between the concentrations at the bottom and the dome is evaluated using the Fenske equation and is complemented with the equations proposed by Underwood and Gilliland. The results of this procedure are consistent with those obtained using a fast method widely validated in the relevant literature.

  5. Batch Mode Data Analysis at ORNL for Radiation Portal Monitoring

    International Nuclear Information System (INIS)

    The Global Nuclear Security Technology Division at Oak Ridge National Laboratory (ORNL) has developed two batch-mode data analysis tools to address the volume of data generated by radiation portal monitors (RPMs) deployed by the Second Line of Defense (SLD). The first of these tools, the ORNL Data Portal (ORNLDP), serves as both a repository and an analysis environment for the data generated by RPMs. The second tool, the In-Country Analysis Tool (ICAT), is portable and serves primarily as a small-scale analysis environment.

  6. Induction of secondary metabolism of Aspergillus terreus ATCC 20542 in the batch bioreactor cultures.

    Science.gov (United States)

    Boruta, Tomasz; Bizukojc, Marcin

    2016-04-01

    Cultivation of Aspergillus terreus ATCC 20542 in a stirred tank bioreactor was performed to induce the biosynthesis of secondary metabolites and provide the bioprocess-related insights into the metabolic capabilities of the investigated strain. The activation of biosynthetic routes was attempted by the diversification of process conditions and growth media. Several strategies were tested, including the addition of rapeseed oil or inulin, changing the concentration of nitrogen source, reduction of chlorine supply, cultivation under saline conditions, and using various aeration schemes. Fifteen secondary metabolites were identified in the course of the study by using ultra-high performance liquid chromatography coupled with mass spectrometry, namely mevinolinic acid, 4a,5-dihydromevinolinic acid, 3α-hydroxy-3,5-dihydromonacolin L acid, terrein, aspulvinone E, dihydroisoflavipucine, (+)-geodin, (+)-bisdechlorogeodin, (+)-erdin, asterric acid, butyrolactone I, desmethylsulochrin, questin, sulochrin, and demethylasterric acid. The study also presents the collection of mass spectra that can serve as a resource for future experiments. The growth in a salt-rich environment turned out to be strongly inhibitory for secondary metabolism and the formation of dense and compact pellets was observed. Generally, the addition of inulin, reducing the oxygen supply, and increasing the content of nitrogen source did not enhance the production of examined molecules. The most successful strategy involved the addition of rapeseed oil to the chlorine-deficient medium. Under these conditions, the highest levels of butyrolactone I, asterric acid, and mevinolinic acid were achieved and the presence of desmethylsulochrin and (+)-bisdechlorogeodin was detected in the broth. The constant and relatively high aeration rate in the idiophase was shown to be beneficial for terrein and (+)-geodin biosynthesis.

  7. PH Control of Monoraphidium Minutum Grown in a Batch Culture Environment

    OpenAIRE

    Stephen M. LaConte; Zeiler, Kathryn G.

    1996-01-01

    Research at the National Renewable Energy Laboratory (NREL) is being conducted to develop low-cost technology for coupling the exhaust from fossil fuel-fired power plants to the growth of microalgae for the dual purpose of recycling carbon dioxide emissions and producing a renewable fuel source. Microalgae are unicellular photosynthesizers with tremendous potential for rapid division (growth) and high lipid production. The carbon assimilated into lipids provides a renewable source for biodies...

  8. Plasmid Instability in Batch Cultures of Recombinant Bacteria. A Laboratory Experiment.

    Science.gov (United States)

    Bentley, William E.; Kompala, Dhinakar S.

    1990-01-01

    Described is a laboratory experiment designed to expose students to problem-solving methods individually and as a group. Included are background information, a list of materials, laboratory procedures, analysis methods, and probable results. (CW)

  9. Comparison of growth, acetate production, and acetate inhibition of Escherichia coli strains in batch and fed-batch fermentations.

    Science.gov (United States)

    Luli, G W; Strohl, W R

    1990-04-01

    The growth characteristics and acetate production of several Escherichia coli strains were compared by using shake flasks, batch fermentations, and glucose-feedback-controlled fed-batch fermentations to assess the potential of each strain to grow at high cell densities. Of the E. coli strains tested, including JM105, B, W3110, W3100, HB101, DH1, CSH50, MC1060, JRG1046, and JRG1061, strains JM105 and B were found to have the greatest relative biomass accumulation, strain MC1060 accumulated the highest concentrations of acetic acid, and strain B had the highest growth rates under the conditions tested. In glucose-feedback-controlled fed-batch fermentations, strains B and JM105 produced only 2 g of acetate.liter-1 while accumulating up to 30 g of biomass.liter-1. Under identical conditions, strains HB101 and MC1060 accumulated less than 10 g of biomass.liter-1 and strain MC1060 produced 8 g of acetate.liter-1. The addition of various concentrations of sodium acetate to the growth medium resulted in a logarithmic decrease, with respect to acetate concentration, in the growth rates of E. coli JM105, JM105(pOS4201), and JRG1061. These data indicated that the growth of the E. coli strains was likely to be inhibited by the acetate they produced when grown on media containing glucose. A model for the inhibition of growth of E. coli by acetate was derived from these experiments to explain the inhibition of acetate on E. coli strains at neutral pH. PMID:2187400

  10. Detection and isolation of Bluetongue virus from commercial vaccine batches.

    Science.gov (United States)

    Bumbarov, Velizar; Golender, Natalia; Erster, Oran; Khinich, Yevgeny

    2016-06-14

    In this report we describe the detection and identification of Bluetongue virus (BTV) contaminations in commercial vaccines. BTV RNA was detected in vaccine batches of Lumpy skin disease (LSD) and Sheep pox (SP) using quantitative PCR (qPCR) for VP1 and NS3 genes. Both batches were positive for VP1 and NS3 in qPCR. The LSD vaccine-derived sample was positive for VP1 and VP2 in conventional PCR. The SP vaccine-derived sample was examined by amplification of VP1, VP4, VP6, VP7, NS2 and NS3 gene segments in conventional PCR. The SP vaccine-derived sample was further propagated in embryonated chicken eggs (ECE) and Vero cells. Preliminary sequence analysis showed that the LSD vaccine-derived sequence was 98-99% similar to BTV9. Analysis of the six genomic segments from the SP vaccine-derived isolate showed the highest similarity to BTV26 (66.3-97.8%). These findings are particularly important due to the effect of BTV on cattle and sheep, for which the vaccines are intended. They also demonstrate the necessity of rigorous vaccine inspection and strict vaccine production control. PMID:27171751

  11. BEclear: Batch Effect Detection and Adjustment in DNA Methylation Data.

    Science.gov (United States)

    Akulenko, Ruslan; Merl, Markus; Helms, Volkhard

    2016-01-01

    Batch effects describe non-natural variations of, for example, large-scale genomic data sets. If not corrected by suitable numerical algorithms, batch effects may seriously affect the analysis of these datasets. The novel array platform independent software tool BEclear enables researchers to identify those portions of the data that deviate statistically significant from the remaining data and to replace these portions by typical values reconstructed from neighboring data entries based on latent factor models. In contrast to other comparable methods that often use some sort of global normalization of the data, BEclear avoids changing the apparently unaffected parts of the data. We tested the performance of this approach on DNA methylation data for various tumor data sets taken from The Cancer Genome Atlas and compared the results to those obtained with the existing algorithms ComBat, Surrogate Variable Analysis, RUVm and Functional normalization. BEclear constantly performed at par with or better than these methods. BEclear is available as an R package at the Bioconductor project http://bioconductor.org/packages/release/bioc/html/BEclear.html. PMID:27559732

  12. Transfer bonding technology for batch fabrication of SMA microactuators

    Science.gov (United States)

    Grund, T.; Guerre, R.; Despont, M.; Kohl, M.

    2008-05-01

    Currently, the broad market introduction of shape memory alloy (SMA) microactuators and sensors is hampered by technological barriers, since batch fabrication methods common to electronics industry are not available. The present study intends to overcome these barriers by introducing a wafer scale transfer process that allows the selective transfer of heat-treated and micromachined shape memory alloy (SMA) film or foil microactuators to randomly selected receiving sites on a target substrate. The technology relies on a temporary adhesive bonding layer between SMA film/foil and an auxiliary substrate, which can be removed by laser ablation. The transfer technology was tested for microactuators of a cold-rolled NiTi foil of 20 μm thickness, which were heat-treated in free-standing condition, then micromachined on an auxiliary substrate of glass, and finally selectively transferred to different target substrates of a polymer. For demonstration, the new technology was used for batch-fabrication of SMA-actuated polymer microvalves.

  13. SEQUENCING BATCH REACTOR: A PROMISING TECHNOLOGY IN WASTEWATER TREATMENT

    Directory of Open Access Journals (Sweden)

    A. H. Mahvi

    2008-04-01

    Full Text Available Discharge of domestic and industrial wastewater to surface or groundwater is very dangerous to the environment. Therefore treatment of any kind of wastewater to produce effluent with good quality is necessary. In this regard choosing an effective treatment system is important. Sequencing batch reactor is a modification of activated sludge process which has been successfully used to treat municipal and industrial wastewater. The process could be applied for nutrients removal, high biochemical oxygen demand containing industrial wastewater, wastewater containing toxic materials such as cyanide, copper, chromium, lead and nickel, food industries effluents, landfill leachates and tannery wastewater. Of the process advantages are single-tank configuration, small foot print, easily expandable, simple operation and low capital costs. Many researches have been conducted on this treatment technology. The authors had been conducted some investigations on a modification of sequencing batch reactor. Their studies resulted in very high percentage removal of biochemical oxygen demand, chemical oxygen demand, total kjeldahl nitrogen, total nitrogen, total phosphorus and total suspended solids respectively. This paper reviews some of the published works in addition to experiences of the authors.

  14. BEclear: Batch Effect Detection and Adjustment in DNA Methylation Data

    Science.gov (United States)

    Akulenko, Ruslan; Merl, Markus; Helms, Volkhard

    2016-01-01

    Batch effects describe non-natural variations of, for example, large-scale genomic data sets. If not corrected by suitable numerical algorithms, batch effects may seriously affect the analysis of these datasets. The novel array platform independent software tool BEclear enables researchers to identify those portions of the data that deviate statistically significant from the remaining data and to replace these portions by typical values reconstructed from neighboring data entries based on latent factor models. In contrast to other comparable methods that often use some sort of global normalization of the data, BEclear avoids changing the apparently unaffected parts of the data. We tested the performance of this approach on DNA methylation data for various tumor data sets taken from The Cancer Genome Atlas and compared the results to those obtained with the existing algorithms ComBat, Surrogate Variable Analysis, RUVm and Functional normalization. BEclear constantly performed at par with or better than these methods. BEclear is available as an R package at the Bioconductor project http://bioconductor.org/packages/release/bioc/html/BEclear.html. PMID:27559732

  15. Treatemnt of Wastewater with Modified Sequencing Batch Biofilm Reactor Technology

    Institute of Scientific and Technical Information of China (English)

    胡龙兴; 刘宇陆

    2002-01-01

    This paper describes the removel of COD and nitrogen from wastewater with modified sequencing batch biofilm reactor,The strategy of simultaneous feeding and draining was explored.The results show that introduction of a new batch of wastewater and withdrawal of the purifeid water can be conducted simultaneously with the maximum volumetric exchange rate of about 70%,Application of this feeding and draining mode leads to the reduction of the cycle time,the increase of the utilization of the reactor volume and the simplification of the reactor structure.The treatment of a synthetic wastewater containing COD and nitrogen was investigated.The operation mode of F(D)-O(i.e.,simultaneous feeding and draining followed by the aerobic condition)was adopted.It was found that COD was degraded very fast in the initial reaction period of time,then reduced slowly and the ammonia nitrogen and nitrate nitrogen concentrations decreased and increased with time respectively,while the nitrite nitrogen level increased first and then reduced.The relationship between the COD or ammonia nitrogen loading and its removal rate was examined,and the removal of COD,ammonia nitrogen and total nitrogen could exceed 95%,90%and 80% respectively,The fact that nitrogen could e removed more completely under constant aeration(aerobic condition)of the SBBR operation mode is very interesting and could be explained in several respects.

  16. Batch Attribute-Based Encryption for Secure Clouds

    Directory of Open Access Journals (Sweden)

    Chen Yang

    2015-10-01

    Full Text Available Cloud storage is widely used by organizations due to its advantage of allowing universal access with low cost. Attribute-based encryption (ABE is a kind of public key encryption suitable for cloud storage. The secret key of each user and the ciphertext are associated with an access policy and an attribute set, respectively; in addition to holding a secret key, one can decrypt a ciphertext only if the associated attributes match the predetermined access policy, which allows one to enforce fine-grained access control on outsourced files. One issue in existing ABE schemes is that they are designed for the users of a single organization. When one wants to share the data with the users of different organizations, the owner needs to encrypt the messages to the receivers of one organization and then repeats this process for another organization. This situation is deteriorated with more and more mobile devices using cloud services, as the ABE encryption process is time consuming and may exhaust the power supplies of the mobile devices quickly. In this paper, we propose a batch attribute-based encryption (BABE approach to address this problem in a provably-secure way. With our approach, the data owner can outsource data in batches to the users of different organizations simultaneously. The data owner is allowed to decide the receiving organizations and the attributes required for decryption. Theoretical and experimental analyses show that our approach is more efficient than traditional encryption implementations in computation and communication.

  17. Mixed culture of Mycotorula japonia and Pseudomonas oleovorans on two hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Miura, Y.; Sugiura, K.; Yoh, M.; Tanaka, H.; Okazaki, M.; Komemushi, S.

    1978-01-01

    A mixed culture system of Mycotorula japonica IAM 4185 and Pseudomonas oleovorans IFO 12570 was established on two carbon sources, n-tetradecane and phenol, as a model for the treatment of petroleum wastes. Characteristics of this system were investigated in batch and continous cultures. The two microbes exhibited commensalism with participation of biotin; P. oleovorans excreted biotin vitamer, which M. japonica required for growth. The former assimilated phenol and the latter mainly n-tetradecane in batch culture. In continous culture, this system was unstable and an oscillatory phenomenon was observed for a long period.

  18. Bagasse hydrolyzates from Agave tequilana as substrates for succinic acid production by Actinobacillus succinogenes in batch and repeated batch reactor.

    Science.gov (United States)

    Corona-González, Rosa Isela; Varela-Almanza, Karla María; Arriola-Guevara, Enrique; Martínez-Gómez, Álvaro de Jesús; Pelayo-Ortiz, Carlos; Toriz, Guillermo

    2016-04-01

    The aim of this work was to obtain fermentable sugars by enzymatic or acid hydrolyses of Agave tequilana Weber bagasse in order to produce succinic acid with Actinobacillus succinogenes. Hydrolyses were carried out with mineral acids (sulfuric and hydrochloric acids) or a commercial cellulolytic enzyme, and were optimized statistically by a response surface methodology, having as factors the concentration of acid/enzyme and time of hydrolysis. The concentration of sugars obtained at optimal conditions for each hydrolysis were 21.7, 22.4y 19.8g/L for H2SO4, HCl and the enzymatic preparation respectively. Concerning succinic acid production, the enzymatic hydrolyzates resulted in the highest yield (0.446g/g) and productivity (0.57g/Lh) using A. succinogenes in a batch reactor system. Repeated batch fermentation with immobilized A. succinogenes in agar and with the enzymatic hydrolyzates resulted in a maximum concentration of succinic acid of 33.6g/L from 87.2g/L monosaccharides after 5 cycles in 40h, obtaining a productivity of 1.32g/Lh. PMID:26802183

  19. Intact cell mass spectrometry as a progress tracking tool for batch and fed-batch fermentation processes.

    Science.gov (United States)

    Helmel, Michaela; Marchetti-Deschmann, Martina; Raus, Martin; Posch, Andreas E; Herwig, Christoph; Šebela, Marek; Allmaier, Günter

    2015-02-01

    Penicillin production during a fermentation process using industrial strains of Penicillium chrysogenum is a research topic permanently discussed since the accidental discovery of the antibiotic. Intact cell mass spectrometry (ICMS) can be a fast and novel monitoring tool for the fermentation progress during penicillin V production in a nearly real-time fashion. This method is already used for the characterization of microorganisms and the differentiation of fungal strains; therefore, the application of ICMS to samples directly harvested from a fermenter is a promising possibility to get fast information about the progress of fungal growth. After the optimization of the ICMS method to penicillin V fermentation broth samples, the obtained ICMS data were evaluated by hierarchical cluster analysis or an in-house software solution written especially for ICMS data comparison. Growth stages of a batch and fed-batch fermentation of Penicillium chrysogenum are differentiated by one of those statistical approaches. The application of two matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) instruments in the linear positive ion mode from different vendors demonstrated the universal applicability of the developed ICMS method. The base for a fast and easy-to-use method for monitoring the fermentation progress of P. chrysogenum is created with this ICMS method developed especially for fermentation broth samples.

  20. Transcriptional response of P. pastoris in fed-batch cultivations to Rhizopus oryzae lipase production reveals UPR induction

    Directory of Open Access Journals (Sweden)

    Valero Francisco

    2007-07-01

    Full Text Available Abstract Background The analysis of transcriptional levels of the genes involved in protein synthesis and secretion is a key factor to understand the host organism's responses to recombinant protein production, as well as their interaction with the cultivation conditions. Novel techniques such as the sandwich hybridization allow monitoring quantitatively the dynamic changes of specific RNAs. In this study, the transcriptional levels of some genes related to the unfolded protein response (UPR and central metabolism of Pichia pastoris were analysed during batch and fed-batch cultivations using an X-33-derived strain expressing a Rhizopus oryzae lipase under control of the formaldehyde dehydrogenase promoter (FLD1, namely the alcohol oxidase gene AOX1, the formaldehyde dehydrogenase FLD1, the protein disulfide isomerase PDI, the KAR2 gene coding for the BiP chaperone, the 26S rRNA and the R. oryzae lipase gene ROL. Results The transcriptional levels of the selected set of genes were first analysed in P. pastoris cells growing in shake flask cultures containing different carbon and nitrogen sources combinations, glycerol + ammonium, methanol + methylamine and sorbitol + methylamine. The transcriptional levels of the AOX1 and FLD1 genes were coherent with the known regulatory mechanism of C1 substrates in P. pastoris, whereas ROL induction lead to the up-regulation of KAR2 and PDI transcriptional levels, thus suggesting that ROL overexpression triggers the UPR. This was further confirmed in fed-batch cultivations performed at different growth rates. Transcriptional levels of the analysed set of genes were generally higher at higher growth rates. Nevertheless, when ROL was overexpressed in a strain having the UPR constitutively activated, significantly lower relative induction levels of these marker genes were detected. Conclusion The bead-based sandwich hybridization assay has shown its potential as a reliable instrument for quantification of

  1. Citric acid production from hydrolysate of pretreated straw cellulose by Yarrowia lipolytica SWJ-1b using batch and fed-batch cultivation.

    Science.gov (United States)

    Liu, Xiaoyan; Lv, Jinshun; Zhang, Tong; Deng, Yuanfang

    2015-01-01

    In this study, crude cellulase produced by Trichoderma reesei Rut-30 was used to hydrolyze pretreated straw. After the compositions of the hydrolysate of pretreated straw were optimized, the study showed that natural components of pretreated straw without addition of any other components such as (NH4)2SO4, KH2PO4, or Mg(2+) were suitable for citric acid production by Yarrowia lipolytica SWJ-1b, and the optimal ventilatory capacity was 10.0 L/min/L medium. Batch and fed-batch production of citric acid from the hydrolysate of pretreated straw by Yarrowia lipolytica SWJ-1b has been investigated. In the batch cultivation, 25.4 g/L and 26.7 g/L citric acid were yields from glucose and hydrolysate of straw cellulose, respectively, while the cultivation time was 120 hr. In the three-cycle fed-batch cultivation, citric acid (CA) production was increased to 42.4 g/L and the cultivation time was extended to 240 hr. However, iso-citric acid (ICA) yield in fed-batch cultivation (4.0 g/L) was similar to that during the batch cultivation (3.9 g/L), and only 1.6 g/L of reducing sugar was left in the medium at the end of fed-batch cultivation, suggesting that most of the added carbon was used in the cultivation.

  2. Biological Treatment of Leachate using Sequencing Batch Reactor

    Directory of Open Access Journals (Sweden)

    WDMC Perera

    2014-12-01

    Full Text Available Normal 0 false false false EN-US X-NONE TA Abstract   In Sri Lanka municipal solid waste is generally disposed in poorly managed open dumps which lack liner systems and leachate collection systems. Rain water percolates through the waste layers to produce leachate which drains in to ground water and finally to nearby water bodies, degrading the quality of water. Leachate thus has become a major environmental concern in municipal waste management and treatment of leachate is a major challenge for the existing and proposed landfill sites.   The study was conducted to assess the feasibility of the usage of the Sequencing Batch Reactor in the treatment of the landfill leachate up to the proposed levels in the draft report of “Proposed Sri Lankan standard for landfill leachate to be disposed to the inland waters". Leachate collected from the open dumpsite at Meethotamulla, Western Province, Sri Lanka was used for leachate characterization.   SBR was constructed with a 10-liter working volume operated in an 18 hour cycle mode and each cycle consists of 15hours of aerobic, 2h settle and 0.5 h of fill/decant stages. The Dissolved Oxygen level within the SBR was maintained at 2 mg/l through the aerobic stage. Infeed was diluted with water during the acclimatization period and a leachate to water ratio of 55:45 was maintained. The removal efficiencies for different parameters were; COD (90.5%, BOD (92.6%, TS (92.1%, Conductivity (83.9%, Alkalinity (97.4%, Hardness (82.2%, Mg (80.5%, Fe (94.2%, Zn (63.4%, Cr (31.69%, Pb (99.6%, Sulphate (98.9%, and Phosphorus (71.4% respectively. In addition Ni and Cd were removed completely during a single SBR cycle. Thus the dilution of leachate in the dumpsites using municipal wastewater, groundwater or rainwater was identified as the most cost effective dilution methods. The effluent from the Sequencing batch reactor is proposed to be further treated using a constructed wetland before releasing to surface water.

  3. Two-stage assembly-type flowshop batch scheduling problem subject to a fixed job sequence

    OpenAIRE

    F J Hwang; B M T Lin

    2012-01-01

    This paper discusses a two-stage assembly-type flowshop scheduling problem with batching considerations subject to a fixed job sequence. The two-stage assembly flowshop consists of m stage-1 parallel dedicated machines and a stage-2 assembly machine which processes the jobs in batches. Four regular performance metrics, namely, the total completion time, maximum lateness, total tardiness, and number of tardy jobs, are considered. The goal is to obtain an optimal batching decision for the prede...

  4. A CATASTROPHIC-CUM-RESTORATIVE QUEUING SYSTEM WITH CORRELATED BATCH ARRIVALS AND VARIABLE CAPACITY

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar

    2008-07-01

    Full Text Available In this paper, we study a catastrophic-cum-restorative queuing system with correlated batch arrivals and service in batches of variable sizes. We perform the transient analysis of the queuing model. We obtain the Laplace Transform of the probability generating function of system size. Finally, some particular cases of the model have been derived and discussed. Keywords: Queue length, Catastrophes, Correlated batch arrivals, Broadband services, Variable service capacity, and Restoration.

  5. Sample Results From Routine Salt Batch 7 Samples

    Energy Technology Data Exchange (ETDEWEB)

    Peters, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-01-14

    Strip Effluent Hold Tank (SEHT) and Decontaminated Salt Solution Hold Tank (DSSHT) samples from several of the “microbatches” of Integrated Salt Disposition Project (ISDP) Salt Batch (“Macrobatch”) 7B have been analyzed for 238Pu, 90Sr, 137Cs, cations (Inductively Coupled Plasma Emission Spectroscopy - ICPES), and anions (Ion Chromatography Anions - IC-A). The analytical results from the current microbatch samples are similar to those from previous macrobatch samples. The Actinide Removal Process (ARP) and the Modular Caustic-Side Solvent Extraction Unit (MCU) continue to show more than adequate Pu and Sr removal, and there is a distinct positive trend in Cs removal (increasing cesium decontamination), due to the use of the Next Generation Solvent (NGS). The bulk chemistry of the DSSHT and SEHT samples do not show any signs of unusual behavior.

  6. Study on the numerical simulation of batch sieving process

    Institute of Scientific and Technical Information of China (English)

    JIAO Hong-guang; MA Jiao; ZHAO Yue-min; CHEN Lun-jian

    2006-01-01

    Screening was widely used in many sectors of industry. However, it is rather incomplete to the cognition of the sieving process for us due to the daedal separation process involving interactions of thousands of particulates. To address this problem, two dimensional numerical simulation of batch sieving process was performed by adopting advanced discrete element method (DEM), which is one of the highly nonlinear digitized dynamic simulative methods and can be used to reveal the quantitative change from particle dimension level. DEM simulation results show that the jam phenomena of sieve-plate apertures of the "blinding particles" in the screen feed can be demonstrated vividly and results also reveal that the velocity of particle moving on the screen plate will vary along with the screen length. This conclusion will be helpful to the design and operation of screen.

  7. Simulated annealing and joint manufacturing batch-sizing

    Directory of Open Access Journals (Sweden)

    Sarker Ruhul

    2003-01-01

    Full Text Available We address an important problem of a manufacturing system. The system procures raw materials from outside suppliers in a lot and processes them to produce finished goods. It proposes an ordering policy for raw materials to meet the requirements of a production facility. In return, this facility has to deliver finished products demanded by external buyers at fixed time intervals. First, a general cost model is developed considering both raw materials and finished products. Then this model is used to develop a simulated annealing approach to determining an optimal ordering policy for procurement of raw materials and also for the manufacturing batch size to minimize the total cost for meeting customer demands in time. The solutions obtained were compared with those of traditional approaches. Numerical examples are presented. .

  8. CONSOLIDATING BATCH AND TRANSACTIONAL WORKLOADS USING DEPENDENCY STRUCTURE PRIORITIZATION

    Directory of Open Access Journals (Sweden)

    S.NIVETHITHA

    2013-04-01

    Full Text Available Organizations offer efficient services to their customers through cloud. These services can either be a batch or transactional workloads. To offer a real-time service, there comes a need to schedule these workloads in an efficient way. An idea to consolidate these workloads enables us to cut down the energy consumption and infrastructure cost. It will be harder to consolidate both these workloads due to the difference in their nature, performance goals and control mechanisms. The proposed work implements the concept of Dependency Structure Prioritization (DSP to assign priority to the job. This work tends to make effective resource utilization through reducing the number of job migration and missed deadline jobs by considering the deadline and the priority of the job as the most important evaluation factor.

  9. [Neural network detection of abnormalities in fed-batch fermentation].

    Science.gov (United States)

    Li, Yun-Feng; Yuan, Jing-Qi

    2005-01-01

    During fermentation, it is often difficult to detect the abnormalities, for example, caused by contamination on-line. Instead, the faults were detected usually by off-line laboratory analysis or other ways, which in most cases, is too late to remedy the situation. In this paper, a simple three-layers BP network was used for the early prediction of the amount of product, based on the difference in prediction errors between normal and abnormal charges and other accessorial information, such as profit function and pH value. In addition, three indications characteristic to abnormal charge are incorporated in practical operation. The prediction for Cephalosporin C Fed-batch Fermentation in a Chinese pharmaceutical factory was studied in details as an example and the result shows the abnormal charge can be discovered early successfully using the method. PMID:15859337

  10. Analytical study plan: Shielded Cells batch 1 campaign; Revision 1

    International Nuclear Information System (INIS)

    Radioactive operations in the Defense Waste Processing Facility (DWPF) will require that the Savannah River Technology Center (SRTC) perform analyses and special studies with actual Savannah River Site (SRS) high-level waste sludge. SRS Tank 42 and Tank 51 will comprise the first batch of sludge to be processed in the DWPF. Approximately 25 liters of sludge from each of these tanks will be characterized and processed in the Shielded Cells of SRTC. During the campaign, processes will include sludge characterization, sludge washing, rheology determination, mixing, hydrogen evolution, feed preparation, and vitrification of the waste. To complete the campaign, the glass will be characterized to determine its durability and crystallinity. This document describes the types of samples that will be produced, the sampling schedule and analyses required, and the methods for sample and analytical control

  11. Hadoop distributed batch processing for Gaia: a success story

    Science.gov (United States)

    Riello, Marco

    2015-12-01

    The DPAC Cambridge Data Processing Centre (DPCI) is responsible for the photometric calibration of the Gaia data including the low resolution spectra. The large data volume produced by Gaia (~26 billion transits/year), the complexity of its data stream and the self-calibrating approach pose unique challenges for scalability, reliability and robustness of both the software pipelines and the operations infrastructure. DPCI has been the first in DPAC to realise the potential of Hadoop and Map/Reduce and to adopt them as the core technologies for its infrastructure. This has proven a winning choice allowing DPCI unmatched processing throughput and reliability within DPAC to the point that other DPCs have started following our footsteps. In this talk we will present the software infrastructure developed to build the distributed and scalable batch data processing system that is currently used in production at DPCI and the excellent results in terms of performance of the system.

  12. Hybrid modeling of xanthan gum bioproduction in batch bioreactor.

    Science.gov (United States)

    Zabot, Giovani L; Mecca, Jaqueline; Mesomo, Michele; Silva, Marceli F; Prá, Valéria Dal; de Oliveira, Débora; Oliveira, J Vladimir; Castilhos, Fernanda; Treichel, Helen; Mazutti, Marcio A

    2011-10-01

    This work is focused on hybrid modeling of xanthan gum bioproduction process by Xanthomonas campestris pv. mangiferaeindicae. Experiments were carried out to evaluate the effects of stirred speed and superficial gas velocity on the kinetics of cell growth, lactose consumption and xanthan gum production in a batch bioreactor using cheese whey as substrate. A hybrid model was employed to simulate the bio-process making use of an artificial neural network (ANN) as a kinetic parameter estimator for the phenomenological model. The hybrid modeling of the process provided a satisfactory fitting quality of the experimental data, since this approach makes possible the incorporation of the effects of operational variables on model parameters. The applicability of the validated model was investigated, using the model as a process simulator to evaluate the effects of initial cell and lactose concentration in the xanthan gum production.

  13. Uranium Adsorption on Granular Activated Carbon – Batch Testing

    Energy Technology Data Exchange (ETDEWEB)

    Parker, Kent E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Golovich, Elizabeth C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wellman, Dawn M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-09-01

    The uranium adsorption performance of two activated carbon samples (Tusaar Lot B-64, Tusaar ER2-189A) was tested using unadjusted source water from well 299-W19-36. These batch tests support ongoing performance optimization efforts to use the best material for uranium treatment in the Hanford Site 200 West Area groundwater pump-and-treat system. A linear response of uranium loading as a function of the solution-to-solid ratio was observed for both materials. Kd values ranged from ~380,000 to >1,900,000 ml/g for the B-64 material and ~200,000 to >1,900,000 ml/g for the ER2-189A material. Uranium loading values ranged from 10.4 to 41.6 μg/g for the two Tusaar materials.

  14. Treatment of Laboratory Wastewater by Sequence Batch reactor technology

    International Nuclear Information System (INIS)

    These studies were conducted on the characterization and treatment of sewage mixed with waste -water of research and testing laboratory (PCSIR Laboratories Lahore). In this study all the parameters COD, BOD and TSS etc of influent (untreated waste-water) and effluent (treated waste-water) were characterized using the standard methods of examination for water and waste-water. All the results of the analyzed waste-water parameters were above the National Environmental Quality Standards (NEQS) set at National level. Treatment of waste-water was carried out by conventional sequencing batch reactor technique (SBR) using aeration and settling technique in the same treatment reactor at laboratory scale. The results of COD after treatment were reduced from (90-95 %), BOD (95-97 %) and TSS (96-99 %) and the reclaimed effluent quality was suitable for gardening purposes. (author)

  15. Minimum Amount of Slop Cut in Batch Distillation

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The pulse-control operation technique which alternates between total reflux operation and total efflux operation in batch distillation was studied along with the minimum amount of slop cut.Total reflux time was confirmed by dynamic simulation, and total efflux time was adopted by statistic method. For the mixture of hexane and cyclohexane and the traditional constant reflux ratio operation strategy, the amount of slop cut is 1.8-2.1 times of the minimum amount of slop cut; whereas for the pulse-control operation strategy, it is 1.2-1.4 times of the minimum amount of slop cut. So compared with the traditional constant reflux ratio operation, the pulse-control operation can decrease the amount of slop cut and operation time, and meanwhile, enhance separation efficiency and yield.

  16. Analysis of Mixing Characteristics of Batch Stirred Vessels Using the Networks-of-Zones Model

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Batch stirred vessels, being devoid of through flow, cannot be assessed by the classical response technique. However, visible inert tracers can be readily observed in a batch or semi-batch stirred vessel. Visible images of the mixing and dispersion of the tracer present a picture in both space and time of the mixing process. Axi-symmetric networks of backmixed zones were used in an image reconstruction approach to analytically characterize the mixing. Computer generated images were compared with experimental results. The qualitative agreement between the observed and calculated images suggests that the analysis of batch stirred reactors can be used to guide operational strategies to control internal concentration fields.

  17. Lipase-catalysed transesterification of soya bean oil for biodiesel production during continuous batch operation.

    Science.gov (United States)

    Du, Wei; Xu, Yuanyuan; Liu, Dehua

    2003-10-01

    The effects of temperature, oil/alcohol molar ratio and by-product glycerol were studied during Lipozyme TL IM-catalysed continuous batch operation when short-chain alcohols were used as the acyl acceptor. In non-continuous batch operation, the optimal oil/alcohol ratio and temperature were 1:4 and 40-50 degrees C; however, during the continuous batch operation, the optimal oil/alcohol ratio and temperature were 1:1 and 30 degrees C; 95% of enzymic activity remained after 10 batches when isopropanol was adopted to remove by-product glycerol during repeated use of the lipase.

  18. Increased CPC batch size study for Tank 42 sludge in the Defense Waste Processing Facility

    International Nuclear Information System (INIS)

    A series of experiments have been completed at TNX for the sludge-only REDOX adjusted flowsheet using Tank 42 sludge simulant in response to the Technical Task Request HLW/DWPT/TTR-980013 to increase CPC batch sizes. By increasing the initial SRAT batch size, a melter feed batch at greater waste solids concentration can be prepared and thus increase melter output per batch by about one canister. The increased throughput would allow DWPF to dispose of more waste in a given time period thus shortening the overall campaign

  19. Retardation characteristics of radionuclides in geologic media through batch and packed column experiments

    International Nuclear Information System (INIS)

    Batch and packed column experiments are performed to investigate the retardation characteristics of radionuclide,i.e, Cs-137 in geologic media. In batch experiment, the effects of important parameters on the sorption of radionuclide in geologic media, such as nuclide concentration, pH, and particle size are examined. The Kd value obtained from breakthrough curve was compared with that from the batch sorption experiment to investigate the applicability of the Kd value from batch experiment to prediction of radionuclide migration in dynamic flow through porous media. The proposed model of radionuclide migration in porous media is also verified using the experimental results. (Author)

  20. Sludge Batch 2 (Marcobath 3) Flowsheet Studies with Simulants

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, D.C.

    2001-03-02

    Sludge-only process simulations of the Sludge Receipt and Adjustment Tank (SRAT) and the Slurry Mix Evaporator (SME) cycle were conducted for the two most likely scenarios for Sludge Batch 2 (Macrobatch 3). The two scenarios are a roughly 50:50 blend of Tank 8 and Tank 40 washed sludge and Tank 40 washed sludge by itself. The testing used new simulants of Tank 8 and Tank 40 washed sludge prepared at the University of South Carolina. The washing endpoint was about 0.5 moles sodium per liter supernate. This report summarizes both the simulant preparation and process simulation activities. The rheology work requested in the Task Plan will be documented in a separate report. Two scoping SRAT simulations were conducted for Tank 40 sludge. This was followed by a complete SRAT and SME simulation using Sludge Batch 1B acid stoichiometry (137.5 percent). Four scoping SRAT simulations were conducted for the Tank 8/40 blend. Three complete SRAT and SME simulations using blended sludge were then performed. One was at the recommended acid stoichiometry of 125 percent. The second used identical acid stoichiometry with HM levels of noble metals. The final run was at worst case noble metals and assumed complete transfer of the Formic Acid Feed Tank. Testing was completed without any major incidents. Hydrogen flow rates in excess of the design bases (0.65 lbs./hr for the SRAT and 0.23 lbs./hr for the SME) are marked in bold. Full details on the noble metals concentrations can be found in the body of the report.

  1. Integrating PROOF Analysis in Cloud and Batch Clusters

    International Nuclear Information System (INIS)

    High Energy Physics (HEP) analysis are becoming more complex and demanding due to the large amount of data collected by the current experiments. The Parallel ROOT Facility (PROOF) provides researchers with an interactive tool to speed up the analysis of huge volumes of data by exploiting parallel processing on both multicore machines and computing clusters. The typical PROOF deployment scenario is a permanent set of cores configured to run the PROOF daemons. However, this approach is incapable of adapting to the dynamic nature of interactive usage. Several initiatives seek to improve the use of computing resources by integrating PROOF with a batch system, such as Proof on Demand (PoD) or PROOF Cluster. These solutions are currently in production at Universidad de Oviedo and IFCA and are positively evaluated by users. Although they are able to adapt to the computing needs of users, they must comply with the specific configuration, OS and software installed at the batch nodes. Furthermore, they share the machines with other workloads, which may cause disruptions in the interactive service for users. These limitations make PROOF a typical use-case for cloud computing. In this work we take profit from Cloud Infrastructure at IFCA in order to provide a dynamic PROOF environment where users can control the software configuration of the machines. The Proof Analysis Framework (PAF) facilitates the development of new analysis and offers a transparent access to PROOF resources. Several performance measurements are presented for the different scenarios (PoD, SGE and Cloud), showing a speed improvement closely correlated with the number of cores used.

  2. Optimal control of batch emulsion polymerization of vinyl chloride

    Energy Technology Data Exchange (ETDEWEB)

    Damslora, Andre Johan

    1998-12-31

    The highly exothermic polymerization of vinyl chloride (VC) is carried out in large vessels where the heat removal represents a major limitation of the production rate. Many emulsion polymerization reactors are operated in such a way that a substantial part of the heat transfer capacity is left unused for a significant part of the total batch time. To increase the reaction rate so that it matches the heat removal capacity during the course of the reaction, this thesis proposes the use of a sufficiently flexible initiator system to obtain a reaction rate which is high throughout the reaction and real-time optimization to compute the addition policy for the initiator. This optimization based approach provides a basis for an interplay between design and control and between production and research. A simple model is developed for predicting the polymerization rate. The model is highly nonlinear and open-loop unstable and may serve as an interesting case for comparison of nonlinear control strategies. The model is fitted to data obtained in a laboratory scale reactor. Finally, the thesis discusses optimal control of the emulsion polymerization reactor. Reduction of the batch cycle time is of major economic importance, as long as the quality parameters are within their specifications. The control parameterization had a major influence on the performance. A differentiable spline parameterization was applied and the optimization is illustrated in a number of cases. The best performance is obtained when the reactor temperature is obtained when the optimization is combined with some form of closed-loop control of the reactor temperature. 112 refs., 48 figs., 4 tabs.

  3. Fecal culture

    Science.gov (United States)

    Stool culture; Culture - stool ... stool tests are done in addition to the culture, such as: Gram stain of stool Fecal smear ... Giannella RA. Infectious enteritis and proctocolitis and bacterial food poisoning. In: Feldman M, Friedman LS, Brandt LJ, ...

  4. Urine culture

    Science.gov (United States)

    Culture and sensitivity - urine ... when urinating. You also may have a urine culture after you have been treated for an infection. ... when bacteria or yeast are found in the culture. This likely means that you have a urinary ...

  5. Safeguards Culture

    Energy Technology Data Exchange (ETDEWEB)

    Frazar, Sarah L.; Mladineo, Stephen V.

    2012-07-01

    The concepts of nuclear safety and security culture are well established; however, a common understanding of safeguards culture is not internationally recognized. Supported by the National Nuclear Security Administration, the authors prepared this report, an analysis of the concept of safeguards culture, and gauged its value to the safeguards community. The authors explored distinctions between safeguards culture, safeguards compliance, and safeguards performance, and evaluated synergies and differences between safeguards culture and safety/security culture. The report concludes with suggested next steps.

  6. Organizational Culture

    Directory of Open Access Journals (Sweden)

    Adrian HUDREA

    2006-02-01

    Full Text Available Cultural orientations of an organization can be its greatest strength, providing the basis for problem solving, cooperation, and communication. Culture, however, can also inhibit needed changes. Cultural changes typically happen slowly – but without cultural change, many other organizational changes are doomed to fail. The dominant culture of an organization is a major contributor to its success. But, of course, no organizational culture is purely one type or another. And the existence of secondary cultures can provide the basis for change. Therefore, organizations need to understand the cultural environments and values.

  7. Versatile modeling and optimization of fed batch processes for the production of secreted heterologous proteins with Pichia pastoris

    Directory of Open Access Journals (Sweden)

    Gasser Brigitte

    2006-12-01

    Full Text Available Abstract Background Secretion of heterologous proteins depends both on biomass concentration and on the specific product secretion rate, which in turn is not constant at varying specific growth rates. As fed batch processes usually do not maintain a steady state throughout the feed phase, it is not trivial to model and optimize such a process by mathematical means. Results We have developed a model for product accumulation in fed batch based on iterative calculation in Microsoft Excel spreadsheets, and used the Solver software to optimize the time course of the media feed in order to maximize the volumetric productivity. The optimum feed phase consisted of an exponential feed at maximum specific growth rate, followed by a phase with linearly increasing feed rate and consequently steadily decreasing specific growth rate. The latter phase could be modeled also by exact mathematical treatment by the calculus of variations, yielding the explicit shape of the growth function, however, with certain indeterminate parameters. To evaluate the latter, one needs a numerical optimum search algorithm. The explicit shape of the growth function provides additional evidence that the Excel model results in correct data. Experimental evaluation in two independent fed batch cultures resulted in a good correlation to the optimized model data, and a 2.2 fold improvement of the volumetric productivity. Conclusion The advantages of the procedure we describe here are the ease of use and the flexibility, applying software familiar to every scientist and engineer, and rapid calculation which makes predictions extremely easy, so that many options can be tested in silico quickly. Additional options like further biological and technological constraints or different functions for specific productivity and biomass yield can easily be integrated.

  8. Modeling of olive oil degradation and oleic acid inhibition during chemostat and batch cultivation of Bacillus thermoleovorans IHI-91.

    Science.gov (United States)

    Becker, P; Märkl, H

    2000-12-20

    Olive oil degradation by the thermophilic lipolytic strain Bacillus thermoleovorans IHI-91 in chemostat and batch culture was modeled to obtain a general understanding of the underlying principles and limitations of the process and to quantify its stoichiometry. Chemostat experiments with olive oil as the sole carbon source were successfully described using the Monod chemostat model extended by terms for maintenance requirements and wall growth. Maintenance requirements and biomass yield coefficients were in the range reported for mesophiles. For a chemostat experiment at D = 0.3 h(-1) the model was validated up to an olive oil feed concentration of about 3.0 g L(-1) above which an inhibitory effect occurred. Further analysis showed that the liberated oleic acid is the main cause for this inhibition. Using steady-state oleic acid concentrations measured in chemostat experiments with olive oil as substrate it was possible to derive a kinetic expression for oleic acid utilization, showing that a concentration of 430 mg L(-1) leads to a complete growth inhibition. Oleic acid accumulation observed during batch fermentations can be predicted using a model involving growth-associated lipase production and olive oil hydrolysis. Simulations confirmed that this accumulation is the cause for the sudden growth cessation occurring in batch fermentations with higher olive oil start concentrations. Further, an oscillatory behavior, as observed in some chemostat experiments, can also be predicted using the latter model. This work clearly demonstrates that thermophilic lipid degradation by Bacillus thermoleovorans IHI-91 is limited by long-chain fatty acid beta-oxidation rather than oil hydrolysis.

  9. A comparative study of sequencing batch reactor and moving-bed sequencing batch reactor for piggery wastewater treatment

    Directory of Open Access Journals (Sweden)

    Kwannate Sombatsompop

    2011-06-01

    Full Text Available This research aims to comparatively study the efficiency of piggery wastewater treatment by the moving-bed sequencing batch reactor (moving-bed SBR system with held medium, and the conventional sequencing batch reactor (SBR system, by varying the organic load from 0.59 to 2.36 kgCOD/m3.d. The COD treatment efficiency of the SBR and moving-bed SBR was higher than 60% at an organic load of 0.59 kgCOD/m3.d and higher than 80% at the organic loads of 1.18-2.36 kgCOD/m3.d. The BOD removal efficiency was greater than 90% at high organic loads of 1.18-2.36 kgCOD/m3.d. The moving-bed SBR gave TKN removal efficiency of 86-93%, whereas the SBR system exhibited the removal efficiency of 75-87% at all organic loads. The amount of effluent suspended solids for SBR systems exceeded the piggery wastewater limit of 200 mg/L at the organic load of 2.36 kgCOD/m3.d while that for the moving-bed SBR system did not. When the organic load was increased, the moving-bed SBR system yielded better treatment efficiency than that of the SBR system. The wastewater treated by the moving-bed SBR system met the criteria of wastewater standard for pig farms at all organic loads, while that treated by the SBR system was not satisfactory at a high organic load of 2.36 kgCOD/m3.d.

  10. Production of laccase by Coriolus versicolor and its application in decolorization of dyestuffs : (Ⅰ) Production of laccase by batch and repeated-batch processes

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The production of laccase by Coriolus versicolor wasstudied. The effect of cultivation conditions on laccase productionby Coriolus versicolor was examined to obtain optimal medium andcultivation conditions. Both batch and repeated-batch processeswere performed for laccase production. In repeated-batchfermentation with self-immobilized mycelia, total of 14 cycles wereperformed with laccase activity in the range between 3.4 and 14.8U/ml.

  11. Meeting Report: Batch-to-Batch Variability in Estrogenic Activity in Commercial Animal Diets—Importance and Approaches for Laboratory Animal Research

    OpenAIRE

    Heindel, Jerrold J.; vom Saal, Frederick S.

    2007-01-01

    We report information from two workshops sponsored by the National Institutes of Health that were held to a) assess whether dietary estrogens could significantly impact end points in experimental animals, and b) involve program participants and feed manufacturers to address the problems associated with measuring and eliminating batch-to-batch variability in rodent diets that may lead to conflicting findings in animal experiments within and between laboratories. Data were presented at the work...

  12. Metabolic footprint analysis of recombinant Escherichia coli strains during fed-batch fermentations.

    Science.gov (United States)

    Carneiro, Sónia; Villas-Bôas, Silas G; Ferreira, Eugénio C; Rocha, Isabel

    2011-03-01

    Metabolic footprinting has become a valuable analytical approach for the characterization of phenotypes and the distinction of specific metabolic states resulting from environmental and/or genetic alterations. The metabolic impact of heterologous protein production in Escherichia coli cells is of particular interest, since there are numerous cellular stresses triggered during this process that limit the overall productivity, e.g. the stringent response. Because the knowledge on the metabolic responses in recombinant bioprocesses is still scarce, metabolic footprinting can provide relevant information on the intrinsic metabolic adjustments. Thus, the metabolic footprints generated by E. coli W3110 and the ΔrelA mutant strain during recombinant fed-batch fermentations at different experimental conditions were measured and interpreted. The IPTG-induction of the heterologous protein expression resulted in the rapid accumulation of inhibitors of the glyoxylate shunt in the culture broth, suggesting the clearance of this anaplerotic route to replenish the TCA intermediaries withdrawn for the additional formation of the heterologous protein. Nutritional shifts were also critical in the recombinant cellular metabolism, indicating that cells employ diverse strategies to counteract imbalances in the cellular metabolism, including the secretion of certain metabolites that are, most likely, used as a metabolic relief to survival processes. PMID:21152511

  13. Bacteria obtained from a sequencing batch reactor that are capable of growth on dehydroabietic acid.

    Science.gov (United States)

    Mohn, W W

    1995-06-01

    Eleven isolates capable of growth on the resin acid dehydroabietic acid (DhA) were obtained from a sequencing batch reactor designed to treat a high-strength process stream from a paper mill. The isolates belonged to two groups, represented by strains DhA-33 and DhA-35, which were characterized. In the bioreactor, bacteria like DhA-35 were more abundant than those like DhA-33. The population in the bioreactor of organisms capable of growth on DhA was estimated to be 1.1 x 10(6) propagules per ml, based on a most-probable-number determination. Analysis of small-subunit rRNA partial sequences indicated that DhA-33 was most closely related to Sphingomonas yanoikuyae (Sab = 0.875) and that DhA-35 was most closely related to Zoogloea ramigera (Sab = 0.849). Both isolates additionally grew on other abietanes, i.e., abietic and palustric acids, but not on the pimaranes, pimaric and isopimaric acids. For DhA-33 and DhA-35 with DhA as the sole organic substrate, doubling times were 2.7 and 2.2 h, respectively, and growth yields were 0.30 and 0.25 g of protein per g of DhA, respectively. Glucose as a cosubstrate stimulated growth of DhA-33 on DhA and stimulated DhA degradation by the culture. Pyruvate as a cosubstrate did not stimulate growth of DhA-35 on DhA and reduced the specific rate of DhA degradation of the culture. DhA induced DhA and abietic acid degradation activities in both strains, and these activities were heat labile. Cell suspensions of both strains consumed DhA at a rate of 6 mumol mg of protein-1 h-1.(ABSTRACT TRUNCATED AT 250 WORDS)

  14. Industrial cultures

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard

    1996-01-01

    The chapter deals with different paradigms andtheories of cultural development. The problem toexplain change and methods to analyse developmentin different cultures are presented and discussed.......The chapter deals with different paradigms andtheories of cultural development. The problem toexplain change and methods to analyse developmentin different cultures are presented and discussed....

  15. REPORTABLE RADIONUCLIDES IN DWPF SLUDGE BATCH 7A (MACROBATCH 8)

    Energy Technology Data Exchange (ETDEWEB)

    Reboul, S.; Diprete, D.; Click, D.; Bannochie, C.

    2011-12-20

    The Waste Acceptance Product Specifications (WAPS) 1.2 require that the waste producer 'shall report the curie inventory of radionuclides that have half-lives longer than 10 years and that are, or will be, present in concentrations greater than 0.05 percent of the total inventory for each waste type indexed to the years 2015 and 3115.' As part of the strategy to meet WAPS 1.2, the Defense Waste Processing Facility (DWPF) will report for each waste type all radionuclides that have half-lives longer than 10 years and contribute greater than 0.01 percent of the total curie inventory from the time of production through the 1100 year period from 2015 through 3115. The initial list of radionuclides to be reported is based on the design-basis glass identified in the Waste Form Compliance Plan (WCP) and Waste Form Qualification Report. However, it is required that the list be expanded if other radionuclides with half-lives greater than 10 years are identified that meet the 'greater than 0.01% of the curie inventory' criterion. Specification 1.6 of the WAPS, International Atomic Energy Agency Safeguards Reporting for High Level Waste (HLW), requires that the ratio by weights of the following uranium and plutonium isotopes be reported: U-233, U-234, U-235, U-236, and U-238; and Pu-238, Pu-239, Pu-240, Pu-241, and Pu-242. Therefore, the complete list of reportable radionuclides must also include these sets of U and Pu isotopes - and the U and Pu isotopic mass distributions must be identified. The DWPF receives HLW sludge slurry from Savannah River Site (SRS) Tank 40. For Sludge Batch 7a (SB7a), the waste in Tank 40 contained a blend of the heel from Sludge Batch 6 (SB6) and the Sludge Batch 7 (SB7) material transferred to Tank 40 from Tank 51. This sludge blend is also referred to as Macrobatch 8. Laboratory analyses of a Tank 40 sludge sample were performed to quantify the concentrations of pertinent radionuclides in the SB7a waste. Subsequently

  16. SULFATE SOLUBILITY LIMIT VERIFICATION FOR DWPF SLUDGE BATCH 7A

    Energy Technology Data Exchange (ETDEWEB)

    Billings, A.

    2011-04-19

    During processing at the Defense Waste Processing Facility (DWPF), high sulfate concentrations in the feed are a concern to DWPF as it can lead to the formation of a detrimental, sulfate-rich, molten salt phase on the surface of the glass melt pool. To avoid these issues, a sulfate concentration limit was implemented into the Product Composition Control System (PCCS). Related to SB7a frit development efforts, the Savannah River National Laboratory (SRNL) assessed the viability of using the current 0.6 wt % SO{sub 4}{sup 2-} limit set for SB6 (in glass) and the possibility of increasing the SO{sub 4}{sup 2-} solubility limit in PCCS to account for anticipated sulfur concentrations, targeted waste loadings, and inclusion of secondary streams (e.g., Actinide Removal Process (ARP)) with two recommended frits (Frit 418 and Frit 702) for SB7a processing. For a nominal SB7a blend with a 63 inch SB6 heel remaining in Tank 40 (projection SB7a-63), a 0.60 wt% SO{sub 4}{sup 2-} in glass limit was determined for waste loadings of 34 wt% up to 40 wt% with Frit 418 based on crucible melts with batched chemicals. SRNL also examined the inclusion of ARP for the same blending scenario (SB7a-63-ARP) with Frit 418 and at least a 0.6 wt% SO{sub 4}{sup 2-} level, and waste loadings of 34 wt% to 40 wt% were also acceptable. When a visible yellow and/or white sulfate salt layer was visible on the surface of any cooled glass, it was assumed to have surpassed the solubility limit of SO{sub 4}{sup 2-} for that particular composition. All of the glasses fabricated at these concentrations did not exhibit a sulfate rich salt layer on the surface of the glass melt and retained the majority of the batched SO{sub 4}{sup 2-}. At higher levels of SO{sub 4}{sup 2-} 'spiked' into the projected sludge compositions over the aforementioned interval of waste loadings, with Frit 418, low viscosity sulfur layers were observed on the surface of glass melts which confirm exceeding the solubility

  17. 40 CFR 63.489 - Batch front-end process vents-monitoring equipment.

    Science.gov (United States)

    2010-07-01

    ... pressure drop. (B) If the scrubber is subject to regulations in 40 CFR parts 264 through 266 that have... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vents... § 63.489 Batch front-end process vents—monitoring equipment. (a) General requirements. Each owner...

  18. 40 CFR 63.1324 - Batch process vents-monitoring equipment.

    Science.gov (United States)

    2010-07-01

    .... (B) If the scrubber is subject to regulations in 40 CFR parts 264 through 266 that have required a... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents-monitoring... Batch process vents—monitoring equipment. (a) General requirements. Each owner or operator of a...

  19. Monitoring and Characterization of Crystal Nucleation and Growth during Batch Crystallization

    NARCIS (Netherlands)

    Kadam, S.S.

    2012-01-01

    Batch crystallization is commonly used in pharmaceutical, agrochemical, specialty and fine chemicals industry. The advantages of batch crystallization lie in its ease of operation and the relatively simple equipment that can be used. On the other hand a major disadvantage associated with it is the i

  20. Role of batch depletion of broiler houses on the occurrence of Campylobacter spp. in chicken flocks

    DEFF Research Database (Denmark)

    Hald, Birthe; Rattenborg, Erik; Madsen, Mogens

    2001-01-01

    Aims: The effect of batch depletion of broiler houses for campylobacter occurrence in broiler flocks was estimated in 10 flocks, each comprising a separate female and male batch. Methods and Results: The chicks were sampled first bq; cloacal swabs in the broiler houses before the start of the dep...

  1. Degradation of the herbicide mecoprop in an aerobic aquifer determined by laboratory batch studies

    DEFF Research Database (Denmark)

    Heron, Gorm; Christensen, Thomas Højlund

    1992-01-01

    The potential of a shallow aerobic aquifer to degrade the herbicide Mecoprop (2-(2-methyl-4-chlorophenoxy)propionic acid) was evaluated in the laboratory using groundwater and sediment suspension batches. Mecoprop was added to the batches to obtain concentrations of 65, 140, 400 and 1400 μg...

  2. 40 CFR 417.10 - Applicability; description of the soap manufacturing by batch kettle subcategory.

    Science.gov (United States)

    2010-07-01

    ... manufacturing by batch kettle subcategory. 417.10 Section 417.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS SOAP AND DETERGENT MANUFACTURING POINT SOURCE CATEGORY Soap Manufacturing by Batch Kettle Subcategory § 417.10 Applicability; description of the...

  3. Fed-batch fermentation dealing with nitrogen limitation in microbial transglutaminase production by Streptoverticillium mobaraense

    NARCIS (Netherlands)

    Zhu, Y.; Rinzema, A.; Tramper, J.; Bruin, E. de; Bol, J.

    1998-01-01

    In the later stages of a batch fermentation for microbial transglutaminase production by Streptoverticillium mobaraense the availability of a nitrogen source accessible to the microorganism becomes critical. Fed-batch fermentation is investigated with the aim of avoiding this substrate limitation. W

  4. Batch and continuous extraction of bromelain enzyme by reversed micelles

    Directory of Open Access Journals (Sweden)

    Ana Maria Frattini Fileti

    2009-10-01

    Full Text Available The main aim of this study was to optimize the conditions for bromelain extraction by reversed micelles from pineapple juice (Ananas comosus. The purification was carried out in batch extraction and a micro-column with pulsed caps for continuous extraction. The cationic micellar solution was made of BDBAC as a surfactant, isooctane as a solvent and hexanol as a co-solvent. For the batch process, a purification factor of 3 times at the best values of surfactant agent, co-solvent and salt concentrations, pH of the back and forward extractions were, 100 mM, 10% v/v, 1 M, 3.5 and 8, respectively. For the continuous operation, independent variables optimal point was determined: ratio between light phase flow rate and total flow rate equal to 0.67 and 1 second for the time interval between the pulses. This optimal point led to a productivity of 1.29 mL/min and a purification factor of 4.96.Este trabalho teve como objetivo principal otimizar as condições para extração da bromelina do suco do abacaxi (Ananas comosus por micelas reversas. A purificação foi feita usando o processo de extração em batelada e contínuo, este último em uma micro-coluna de campânulas pulsantes. A solução micelar catiônica foi preparada com o surfactante BDBAC, i-octano como solvente e hexanol como co-solvente. Na extração em batelada encontrou-se um fator de purificação de 3 vezes, e seus melhores valores de concentração do agente surfactante, co-solvente e sal, de pH da re-extração e extração, foram respectivamente iguais a: 100 mM, 10% v/v, 1 M, 3,5 e 8. Para a operação contínua, as variáveis independentes ótimas foram: 0,67 para a razão entre as taxas de fluxos da fase leve e a total e 1 s para o intervalo de tempo entre pulsos das campânulas. Este ponto ótimo leva a uma produtividade de 1,29 mL/min e a um fator de purificação igual a 4,96.

  5. Inhibition of Sulfide Mineral Oxidation by Surface Coating Agents: Batch

    Science.gov (United States)

    Choi, J.; Ji, M. K.; Yun, H. S.; Park, Y. T.; Gee, E. D.; Lee, W. R.; Jeon, B.-H.

    2012-04-01

    Mining activities and mineral industries have impacted on rapid oxidation of sulfide minerals such as pyrite (FeS2) which leads to Acid Mine Drainage (AMD) formation. Some of the abandoned mines discharge polluted water without proper environmental remediation treatments, largely because of financial constraints in treating AMD. Magnitude of the problem is considerable, especially in countries with a long history of mining. As metal sulfides become oxidized during mining activities, the aqueous environment becomes acid and rich in many metals, including iron, lead, mercury, arsenic and many others. The toxic heavy metals are responsible for the environmental deterioration of stream, groundwater and soils. Several strategies to remediate AMD contaminated sites have been proposed. Among the source inhibition and prevention technologies, microencapsulation (coating) has been considered as a promising technology. The encapsulation is based on inhibition of O2 diffusion by surface coating agent and is expected to control the oxidation of pyrite for a long time. Potential of several surface coating agents for preventing oxidation of metal sulfide minerals from both Young-Dong coal mine and Il-Gwang gold mine were examined by conducting batch experiments and field tests. Powdered pyrite as a standard sulfide mineral and rock samples from two mine outcrops were mixed with six coating agents (KH2PO4, MgO and KMnO4 as chemical agents, and apatite, cement and manganite as mineral agents) and incubated with oxidizing agents (H2O2 or NaClO). Batch experiments with Young-Dong coal mine samples showed least SO42- production in presence of KMnO4 (16% sulfate production compared to no surface coating agents) or cement (4%) within 8 days. In the case of Il-Gwang mine samples, least SO42- production was observed in presence of KH2PO4 (8%) or cement (2%) within 8 days. Field-scale pilot tests at Il-Gwang site also showed that addition of KH2PO4 decreased sulfate production from 200 to

  6. Case-by-case risk assessment of broiler meat batches: An effective control strategy for Campylobacter

    DEFF Research Database (Denmark)

    Christensen, Bjarke Bak; Nauta, Maarten; Korsgaard, Helle;

    2013-01-01

    In 2006, the Danish government decided to take new measures to control Salmonella and Campylobacter in Danish and imported retail meat. The legal basis for these new measures was article 14 in the EU food law, which states that food shall not be placed on the market if it is unsafe, among others...... and the results of more than 3,000 batches of broiler meat tested since 2007. The risk was assessed for batches with one or more samples positive for Campylobacter (>100 cfu/g). Reductions in the number of positive batches from 2007 to 2010 were observed for both domestic (from 17% to 7%, p=0.01) and imported......, for reasons of contamination. This provision allows each member state to make a specific risk assessment of food batches, and decide whether a batch poses an unacceptable risk to the consumer or not. Here we present the basis for the risk assessment model on Campylobacter used in this new approach...

  7. ORGANIZATIONAL CULTURE AND MANAGEMENT CULTURE

    OpenAIRE

    Tudor Hobeanu; Loredana Vacarescu Hobeanu

    2010-01-01

    Communication reveals the importance of organizational culture and management culture supported by the remarkable results in economic and social level of organization. Their functions are presented and specific ways of expression levels of organizational culture and ways of adapting to the requirements of the organization's management culture.

  8. Biohydrogen production from xylose at extreme thermophilic temperatures (70 degrees C) by mixed culture fermentation

    DEFF Research Database (Denmark)

    Kongjan, Prawit; Min, Booki; Angelidaki, Irini

    2009-01-01

    Biohydrogen production from xylose at extreme thermophilic temperatures (70 degrees C) was investigated in batch and continuous-mode operation. Biohydrogen was successfully produced from xylose by repeated batch cultivations with mixed culture received from a biohydrogen reactor treating household...... high hydrogen partial pressure (>0.14 atm) was present in the headspace of the batch reactors. Biohydrogen could be successfully produced in continuously stirred reactor (CSTR) operated at 72-h hydraulic retention time (HRT) with 1 g/L of xylose as substrate at 70 degrees C. The hydrogen production...

  9. Sample Results from Routine Salt Batch 7 Samples

    Energy Technology Data Exchange (ETDEWEB)

    Peters, T. [Savannah River Site (SRS), Aiken, SC (United States)

    2015-05-13

    Strip Effluent Hold Tank (SEHT) and Decontaminated Salt Solution Hold Tank (DSSHT) samples from several of the “microbatches” of Integrated Salt Disposition Project (ISDP) Salt Batch (“Macrobatch”) 7B have been analyzed for 238Pu, 90Sr, 137Cs, Inductively Coupled Plasma Emission Spectroscopy (ICPES), and Ion Chromatography Anions (IC-A). The results from the current microbatch samples are similar to those from earlier samples from this and previous macrobatches. The Actinide Removal Process (ARP) and the Modular Caustic-Side Solvent Extraction Unit (MCU) continue to show more than adequate Pu and Sr removal, and there is a distinct positive trend in Cs removal, due to the use of the Next Generation Solvent (NGS). The Savannah River National Laboratory (SRNL) notes that historically, most measured Concentration Factor (CF) values during salt processing have been in the 12-14 range. However, recent processing gives CF values closer to 11. This observation does not indicate that the solvent performance is suffering, as the Decontamination Factor (DF) has still maintained consistently high values. Nevertheless, SRNL will continue to monitor for indications of process upsets. The bulk chemistry of the DSSHT and SEHT samples do not show any signs of unusual behavior.

  10. Catalytic hydroliquefaction of coal: about the methodology in batch experiments

    Energy Technology Data Exchange (ETDEWEB)

    Besson, M.; Bacaud, R.; Charcosset, H.; Cebolla-Burillo, V.; Oberson, M.

    1986-03-01

    The results of catalytic hydroliquefaction under batch conditions depend on a large number of variables. The present results concern a few of these variables, in particular the influence of the catalyst concentration, of the mode of sulfidation or (and) of introduction of the catalyst in the coal/solvent mixture, and of the nature of the model compound solvent. The results indicate that increasing the concentration of catalyst increase the conversion of coal into toluene soluble products and the hydrogen consumption but has a small effect on oil formation. An inhibition of the figst fractions of a NiMo/Al/sub 2/O/sub 3/ catalyst added is shown. Strong effects of the sulfiding mode of an iron oxide catalyst, and of the temperature of introduction of the iron oxide into the autoclave are observed relative to the hydrogenation activity of the iron catalyst, when at the same time there is no influence on coal conversions. The replacement of tetralin by a non-donor solvent, 1-methylnaphthalene, suggests that the direct hydrogen transfer process from molecular hydrogen to coal fragment radicals on the catalyst surface may be important. 9 tabs., 4 firs., 16 refs.

  11. Separation of Benzene and Cyclohexane by Batch Extractive Distillation

    Institute of Scientific and Technical Information of China (English)

    XU Jiao; ZHANG Weijiang; GUI Xia

    2007-01-01

    Azeotropic liquid mixture cannot be separated by conventional distillation. But extractive distillation or combination of the two can be valid for them. An experiment to separate benzene and cyclohexane by batch extractive distillation was carried out with N, N-dimethylformide (DMF), dimethyl sulfoxide (DMSO) and their mixture as extractive solvent. The effect of the operation parameterssuch as solvent flow rate and reflux ratio on the separation was studied under the same operating conditions. The results show that the separation effect was improved with the increase of solvent flow rate and the reflux ratio; all the three extractive solvents can separate benzene and cyclohexane, with DMF being the most efficient one, the mixture the second, and DMSO the least. In the experiment the best operation conditions are with DMF as extractive solvent, the solvent flow rate being 12.33 mL/min, and the reflux ratio being 6. As a result, we can get cyclohexane from the top of tower with the average product content being 86.98%, and its recovering ratio being 83.10%.

  12. Design of Batch Pressing Mechanism for Bedded Standard Samples

    Directory of Open Access Journals (Sweden)

    Li Jianguang

    2016-01-01

    Full Text Available In stability analysis of rock soil engineering, before establishing similar physical simulation model, many match experiments on similar material are required, the current standard sample forming processes are difficult to satisfy the uniformity and compactness in the same sample set often, and have obvious defects in the molding process, molding efficiency and bedding processing. A pressing mechanism consists of adjustable concave-convex composite mould, multi-function trough, drive screw and framework is designed, the mould is pressed nto material to fill directly. Each layered material, dip angle, thickness and position can be controlled, forming number for each lot is adjustable, uniform of the same lot is good, all parts are detachable, operation is also simple. This mechanism is suitable for small batch forming, and has obvious advantages in bedding controlling, forming efficiency, forming quality and operation convenience, which can work well for match experiments before large-scale physical similar simulation experiment, geotechnical experiment, composite rock mass experiment, also can be used to make micro physical model with engineering structure.

  13. Microfabrication-derived DDS: From batch to individual production.

    Science.gov (United States)

    Takada, K

    2008-06-01

    As a result of recent advances in microfabrication technology (MFT), microparticles including microcapsules and microspheres can be prepared individually and the disadvantages of the conventional microparticles produced by batch production, i.e. (i) low loading efficiency, (ii) large size variation, and (iii) initial burst release, have been remedied. In addition, all conventional microparticles have the same structure, a spherical shape, so they have only one function, sustained release. Threelayer microcapsules (TLMCs) have been designed to address these issues. TLMCs consist of a surface layer, a drug carrying layer, and a basement layer. TLMCs have sustained release as well as adhesiveness and targeting functions. TLMCs are prepared using ink-jet printer nozzle technology. The obtained TLMCs are used for the oral delivery of peptide/protein drugs and long-term sustained-release injection preparation. In addition, self-dissolving micropiles (SDMPs) can be individually produced by MFT as a percutaneous preparation. MFT allows biopharmaceutical drugs like insulin, erythropoietin, and growth hormone to be absorbed through the skin. Thus, advances in MFT have accelerated the development of pharmaceutical technology.

  14. EFFECT OF DYE CONCENTRATION ON SEQUENCING BATCH REACTOR PERFORMANCE

    Directory of Open Access Journals (Sweden)

    A. A. Vaigan ، M. R. Alavi Moghaddam ، H. Hashemi

    2009-01-01

    Full Text Available Reactive dyes have been identified as problematic compounds in textile industries wastewater as they are water soluble and cannot be easily removed by conventional aerobic biological treatment systems. The treatability of a reactive dye (Brill Blue KN-R by sequencing batch reactor and the influence of the dye concentration on system performance were investigated in this study. Brill Blue KN-R is one of the main dyes that are used in textile industries in Iran. Four cylindrical Plexiglas reactors were run for 36 days (5 days for acclimatization of sludge and 31 days for normal operation at different initial dye concentrations. The dye concentrations were adjusted to be 20, 25, 30 and 40 mg/L in the reactors R1, R2, R3 and R4, respectively. In all reactors, effective volume, influent wastewater flowrate and sludge retention time were 5.5 L, 3.0 L/d and 10 d, respectively. According to the obtained data, average dye removal efficiencies of R1, R2, R3 and R4 were 57% ± 2, 50.18% ± 3, 44.97% ± 3 and 30.98% ± 3, respectively. The average COD removal efficiencies of all reactors were 97% ± 1, 97.12% ± 1, 96.93% ± 1 and 97.22% ± 1, respectively. The dye removal efficiency was decreased by increasing the dye concentration with the correlation coefficient of 0.997.

  15. Simultaneous denitrifying phosphorus accumulation in a sequencing batch reactor

    Institute of Scientific and Technical Information of China (English)

    YUAN Linjiang; HAN Wei; WANG Lei; YANG Yongzhe; WANG Zhiying

    2007-01-01

    In order to achieve simultaneous nitrogen and phosphorus removal in the biological treatment process,denitrifying phosphorus accumulation(DNPA)and its affecting factors were studied in a sequencing batch reactor(SBR)with synthetic wastewater.The results showed that when acetate was used as the sole carbon resource in the influent.the sludge acclimatized under anaerobic/aerobic operation had good phosphorus removal ability.Denitrifying phosphorus accumulation was observed soon when fed with nitrate instead of aeration following the anaerobic stage,which is a vital premise to DNPA.If DNPA sludge is fed with nitrate prior to the anaerobic stage,the DNPA would weaken or even disappear.At the high concen tration of nitrate fed in the anoxic stage,the longer anoxic time needed,the better the DNPA was.Induced DNPA did not disappear even though an aerobic stage followed the anoxic stage,but the shorter the aerobic stage lasted,the higher the proportions of phosphorus removal via DNPA to total removal.

  16. Pretreatment of coking wastewater using anaerobic sequencing batch reactor (ASBR)

    Institute of Scientific and Technical Information of China (English)

    LI Bing; SUN Ying-lan; LI Yu-ying

    2005-01-01

    A laboratory-scale anaerobic sequencing batch reactor (ASBR) was used to pretreat coking wastewater. Inoculated anaerobic granular biomass was acclimated for 225 d to the coking wastewater, and then the biochemical methane potential (BMP)of the coking wastewater in the acclimated granular biomass was measured. At the same time, some fundamental technological factors, such as the filling time and the reacting time ratio (tf/tr), the mixing intensity and the intermittent mixing mode, that affect anaerobic pretreatment of coking wastewater with ASBR, were evaluated through orthogonal tests. The COD removal efficiency reached 38%~50% in the stable operation period with the organic loading rate of 0.37~0.54 kg COD/(m3.d) at the optimum conditions of tf/tr, the mixing intensity and the intermittent mixing mode. In addition, the biodegradability of coking wastewater distinctly increased after the pretreatment using ASBR. At the end of the experiment, the microorganism forms on the granulated sludge in the ASBR were observed using SEM (scanning electron microscope) and fluoroscope. The results showed that the dominant microorganism on the granular sludge was Methanosaeta instead of Methanosarcina dominated on the inoculated sludge.

  17. Degradation of formaldehyde in anaerobic sequencing batch biofilm reactor (ASBBR)

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, N.S. [Laboratorio de Processos Biologicos (LPB), Departamento de Hidraulica e Saneamento, Escola de Engenharia de Sao Carlos (EESC), Universidade de Sao Paulo - USP, Engenharia Ambiental, Bloco 4-F, Av. Joao Dagnone, 1100 Santa Angelina, 13.563-120 Sao Carlos, SP (Brazil); Zaiat, M. [Laboratorio de Processos Biologicos (LPB), Departamento de Hidraulica e Saneamento, Escola de Engenharia de Sao Carlos (EESC), Universidade de Sao Paulo - USP, Engenharia Ambiental, Bloco 4-F, Av. Joao Dagnone, 1100 Santa Angelina, 13.563-120 Sao Carlos, SP (Brazil)], E-mail: zaiat@sc.usp.br

    2009-04-30

    The present study evaluated the degradation of formaldehyde in a bench-scale anaerobic sequencing batch reactor, which contained biomass immobilized in polyurethane foam matrices. The reactor was operated for 212 days at 35 deg. C with 8 h sequential cycles, under different affluent formaldehyde concentrations ranging from 31.6 to 1104.4 mg/L (formaldehyde loading rates from 0.08 to 2.78 kg/m{sup 3} day). The results indicate excellent reactor stability and over 99% efficiency in formaldehyde removal, with average effluent formaldehyde concentration of 3.6 {+-} 1.7 mg/L. Formaldehyde degradation rates increased from 204.9 to 698.3 mg/L h as the initial concentration of formaldehyde was increased from around 100 to around 1100 mg/L. However, accumulation of organic matter was observed in the effluent (chemical oxygen demand (COD) values above 500 mg/L) due to the presence of non-degraded organic acids, especially acetic and propionic acids. This observation poses an important question regarding the anaerobic route of formaldehyde degradation, which might differ substantially from that reported in the literature. The anaerobic degradation pathway can be associated with the formation of long-chain oligomers from formaldehyde. Such long- or short-chain polymers are probably the precursors of organic acid formation by means of acidogenic anaerobic microorganisms.

  18. Changes of Resistance During Polyelectrolyte-enhanced Stirred Batch Ultrafiltration

    Institute of Scientific and Technical Information of China (English)

    ZHU Xin-Sheng; Kwang-Ho CHOO

    2007-01-01

    The permeation flux or the resistance in the ultrafiltration process is mainly limited by osmotic pressure,and it may originate from various kinds of polymer interactions. However, the real origin of permeation resistance hasn't been clarified yet in the light of polymer solution nature. The removal of nitrate contamination by polyelectrolytes was carried out with stirred batch ultrafiltration. The polyelectrolyte concentrations both in permeate and retentate were analyzed with total organic carbon analyzer and permeate mass was acquired by electronic balance connected with computer. The total resistance was calculated and interpreted based on the osmotic pressures in three concentration regimes. In the dilute region, the resistance was proportional to polymer concentration; in the semidilute region, the resistance depended on polymer concentration in the parabolic relationship; in the highly concentrated solution regime, the osmotic pressure factor (OPF) would dominate the total resistance; and the deviation from OPF control could come from the electrostatic repulsion between the tightly compacted and charged polyelectrolyte particles at extremely concentrated solution regime. It was first found that dilute and semidilute concentration regions can be easily detected by plotting the log-log curves of the polymer concentration versus the ratio of the total resistance to polymer concentration. The new concept OPF was defined and did work well at highly concentrated regime.

  19. Kinetic Batch Soil Adsorption Studies of 2, 4-dinitroanisole (DNAN)

    Science.gov (United States)

    Arthur, J.; Mark, N. W.; Taylor, S.; Brusseau, M. L.; Dontsova, K.

    2014-12-01

    Currently the explosive 2, 4, 6- trinitrotoluene (TNT) is used as a main ingredient in munitions; however the compound has failed to meet sensitivity requirements. The replacement compound being tested is 2, 4-dinitroanisole (DNAN). DNAN is less sensitive to shock, high temperatures, and has good detonation characteristics. However, DNAN is more soluble than TNT, which can influence transport and fate behavior and thus bioavailability and exposure potential. DNAN has been shown to have some human and environmental toxicity. The objective of this study was to investigate the environmental fate of DNAN in soil, with a specific focus on sorption processes. Batch experiments were conducted using 11 soils collected from military installations located across the United States. The soils were characterized for pH, specific surface area, electrical conductivity, cation exchange capacity, and organic carbon content. Adsorption kinetic data determined at room temperature were fitted using the first order kinetic equation. Adsorption isotherms were fitted with linear and Freundlich isotherm equations. The magnitudes of the linear adsorption coefficients ranged from 0.6 to 6 cm3/g. Results indicated that the adsorption of DNAN is strongly dependent on the amount of organic carbon present in the soil.

  20. Pembuatan Biodiesel Secara Batch Dengan Memanfaatkan Gelombang Mikro (Microwave

    Directory of Open Access Journals (Sweden)

    Rhesa Purnama Putra

    2012-09-01

    Full Text Available Biodiesel merupakan bioenergi atau bahan bakar nabati yang dibuat dari minyak nabati, baik minyak baru atau bekas penggorengan melalui proses transesterifikasi, esterifikasi, atau proses esterifikasi-transesterifikasi. Tujuan penelitian ini adalah untuk membuat biodiesel dari minyak goreng secara batch melalui proses transesterifikasi dengan menggunakan radiasi mikrowave serta mempelajari berapa daya dan waktu optimal yang diperlukan untuk proses pembuatan biodiesel dengan radiasi microwave dengan katalis CaO, H2SO4, dan tanpa katalis. Dalam penelitian ini digunakan tiga variabel, yaitu daya (Watt;100,200,300,400, waktu (menit; 5,10,15,20 dan jenis katalis; CaO, H2SO4, dan tanpa katalis. Pada tahap persiapan menghitung volume minyak dan metanol yang akan dicampur. Kemudian mencampurnya didalam reaktor. Lalu mendinginkan campuran hingga terbentuk dua lapisan atas dan bawah dilanjutkan dengan melakukan pemisahan lapisan atas (biodiesel dari lapisan bawah (gliserol. Adapun pada tahap analisis, biodiesel hasil reaksi transesterfikasi dianalisa untuk mendapatkan data yield metil ester, densitas, viskositas, dan flash point. Dari penelitian diketahui bahwa hasil yang didapatkan masih belum dapat memenuhi standar biodiesel yang ditetapkan. Katalis CaO dapat memberikan hasil yang lebih baik dibandingkan dengan katalis H2SO4 dan tanpa katalis. Kondisi operasi untuk menghasilkan kualitas yield biodiesel terbaik yaitu pada daya 200 Watt selama 20 menit dengan menggunakan katalis CaO. Yield biodiesel terbesar didapatkan yield sebesar 60,11 %.

  1. Continuous culture methodology for the screening of microalgae for oil

    OpenAIRE

    del Rio, E; Armendáriz, Ana; García-Gómez, Elena; García-González, Mercedes; Guerrero, Miguel G.

    2015-01-01

    A basic criterion in the selection of microalgae suitable as source of oil for biodiesel should be their actual capacity to produce lipids or, more properly, the fatty acid yield. Performance assessment of ten preselected microalgae under both batch and continuous culture points to the latter approach as the most adequate for evaluating fatty acid productivity. Differences were patent in continuous culture among strains that otherwise had analogous oil accumulation potential un...

  2. Community dynamics of complex starter cultures for Gouda-type cheeses and its functional consequences

    OpenAIRE

    Erkus, O.

    2014-01-01

    Lactic acid bacteria (LAB) are used as starter and adjunct cultures for the production of artisanal and industrial fermented milk products such as yoghurt and cheese.  Artisanal fermentations is propagated with the transfer of an inoculum from old batch of fermented food to the new batch (back-slopping) to initiate the fermentation with the activity of the indigenous microbiota present in the inoculum. In industrial production, these inocula with indigenous microbiota are replaced with t...

  3. Grease waste and sewage sludge co-digestion enhancement by thermal hydrolysis: batch and fed-batch assays.

    Science.gov (United States)

    Cano, R; Nielfa, A; Pérez, A; Bouchy, L; Fdz-Polanco, M

    2014-01-01

    Grease waste (GW) is an adequate substrate for sewage sludge co-digestion since, coming from a waste water treatment plant, it has a high methane potential (489 NmLCH(4)/gVSin); however, no synergistic effect takes place when co-digesting with 52%VS grease. Conversely, thermal hydrolysis (TH) improves the anaerobic digestion of GW (43% higher kinetics) and biological sludge (29% more methane potential). Therefore, the application of TH to a co-digestion process was further studied. First, biochemical methane potential tests showed that the best configuration to implement the TH to the co-digestion process is pretreating the biological sludge alone, providing a 7.5% higher methane production (398 NmLCH(4)/gVSin), 20% faster kinetics and no lag-phase. Its implementation in a fed-batch operation resulted in considerable methane production (363 NmLCH(4)/gVSin) and TH improved the rheology and dewaterability properties of the digestate. This leads to important economical savings when combined with co-digestion, reducing final waste management costs and showing interesting potential for full-scale application. PMID:24804667

  4. Shortcut Procedure for Inverted Batch Distillation Column (Ⅰ) Multicomponent Ideal System

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Inverted batch distillation colunm(stripper) is opposed to a conventional batch distillation column(rectifier). It has a storage vessel at the top and products leave the column at the bottom. The batch stripper is favourable to separate mixtures with a small amount of light components by removing the heavy components as bottom products. In this paper, we are presenting a shortcut procedure based on our earlier work for design and simulation of the inverted batch distillation column, which is equivalent to the Fenske-Underwood-Gilliland procedure for continuous distillation. Given a separation task, we propose to compute the minimum number of stages(Nbmin)and the minimum reboil ratio(Rbmin) required in a batch stripper,which are the stages and reboil ratio required in a hypothetical inverted batch distillation colnmn operating in total reboil ratio or having an infinite number of stages,respectively. Then, it is shown that the performance of inverted batch columns with a finite number of stages and reboil ratios could be correlated in Gilliland coordinates with the minimum stages Nbmin and the minimum reboil ratio Rbmin.

  5. Tc-99 Adsorption on Selected Activated Carbons - Batch Testing Results

    Energy Technology Data Exchange (ETDEWEB)

    Mattigod, Shas V.; Wellman, Dawn M.; Golovich, Elizabeth C.; Cordova, Elsa A.; Smith, Ronald M.

    2010-12-01

    CH2M HILL Plateau Remediation Company (CHPRC) is currently developing a 200-West Area groundwater pump-and-treat system as the remedial action selected under the Comprehensive Environmental Response, Compensation, and Liability Act Record of Decision for Operable Unit (OU) 200-ZP-1. This report documents the results of treatability tests Pacific Northwest National Laboratory researchers conducted to quantify the ability of selected activated carbon products (or carbons) to adsorb technetium-99 (Tc-99) from 200-West Area groundwater. The Tc-99 adsorption performance of seven activated carbons (J177601 Calgon Fitrasorb 400, J177606 Siemens AC1230AWC, J177609 Carbon Resources CR-1240-AW, J177611 General Carbon GC20X50, J177612 Norit GAC830, J177613 Norit GAC830, and J177617 Nucon LW1230) were evaluated using water from well 299-W19-36. Four of the best performing carbons (J177606 Siemens AC1230AWC, J177609 Carbon Resources CR-1240-AW, J177611 General Carbon GC20X50, and J177613 Norit GAC830) were selected for batch isotherm testing. The batch isotherm tests on four of the selected carbons indicated that under lower nitrate concentration conditions (382 mg/L), Kd values ranged from 6,000 to 20,000 mL/g. In comparison. Under higher nitrate (750 mg/L) conditions, there was a measureable decrease in Tc-99 adsorption with Kd values ranging from 3,000 to 7,000 mL/g. The adsorption data fit both the Langmuir and the Freundlich equations. Supplemental tests were conducted using the two carbons that demonstrated the highest adsorption capacity to resolve the issue of the best fit isotherm. These tests indicated that Langmuir isotherms provided the best fit for Tc-99 adsorption under low nitrate concentration conditions. At the design basis concentration of Tc 0.865 µg/L(14,700 pCi/L), the predicted Kd values from using Langmuir isotherm constants were 5,980 mL/g and 6,870 mL/g for for the two carbons. These Kd values did not meet the target Kd value of 9,000 mL/g. Tests

  6. SLUDGE BATCH 6/TANK 51 SIMULANT CHEMICAL PROCESS CELL SIMULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, David; Best, David

    2010-04-28

    Qualification simulant testing was completed to determine appropriate processing conditions and assumptions for the Sludge Batch 6 (SB6) Shielded Cells demonstration of the DWPF flowsheet using the qualification sample from Tank 51 for SB6 after SRNL washing. It was found that an acid addition window of 105-139% of the DWPF acid equation (100-133% of the Koopman minimum acid equation) gave acceptable Sludge Receipt and Adjustment Tank (SRAT) and Slurry Mix Evaporator (SME) results for nitrite destruction and hydrogen generation. Hydrogen generation occurred continuously after acid addition in three of the four tests. The three runs at 117%, 133%, and 150% stoichiometry (Koopman) were all still producing around 0.1 lb hydrogen/hr at DWPF scale after 42 hours of boiling in the SRAT. The 150% acid run reached 110% of the DWPF SRAT limit of 0.65 lb H{sub 2}/hr, and the 133% acid run reached 75% of the DWPF SME limit of 0.223 lb H{sub 2}/hr. Conversely, nitrous oxide generation was subdued compared to previous sludge batches, staying below 25 lb/hr in all four tests or about a fourth as much as in comparable SB4 testing. Two other processing issues were noted. First, incomplete mercury suspension impacted mercury stripping from the SRAT slurry. This led to higher SRAT product mercury concentrations than targeted (>0.45 wt% in the total solids). Associated with this issue was a general difficulty in quantifying the mass of mercury in the SRAT vessel as a function of time, especially as acid stoichiometry increased. About ten times more mercury was found after drying the 150% acid SME product to powder than was indicated by the SME product sample results. Significantly more mercury was also found in the 133% acid SME product samples than was found during the SRAT cycle sampling. It appears that mercury is segregating from the bulk slurry in the SRAT vessel, as mercury amalgam deposits for example, and is not being resuspended by the agitators. The second processing issue

  7. Throat Culture

    Science.gov (United States)

    ... limited. Home Visit Global Sites Search Help? Throat Culture Share this page: Was this page helpful? Collecting | ... treatment | Getting results | see BLOOD SAMPLE Collecting A culture is a test that is often used to ...

  8. Repellent Culture.

    Science.gov (United States)

    Carroll, Jeffrey

    2001-01-01

    Considers defining "culture," noting how it is difficult to define because those individuals defining it cannot separate themselves from it. Relates these issues to student writing and their writing improvement. Addresses violence in relation to culture. (SG)

  9. Culturing Protozoa.

    Science.gov (United States)

    Stevenson, Paul

    1980-01-01

    Compares various nutrient media, growth conditions, and stock solutions used in culturing protozoa. A hay infusion in Chalkey's solution maintained at a stable temperature is recommended for producing the most dense and diverse cultures. (WB)

  10. MELT RATE FURNACE TESTING FOR SLUDGE BATCH 5 FRIT OPTIMIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D; Fox, K; Pickenheim, B; Stone, M

    2008-10-03

    Savannah River National Laboratory (SRNL) was requested to provide the Defense Waste Processing Facility (DWPF) with a frit composition for Sludge Batch 5 (SB5) to optimize processing. A series of experiments were designed for testing in the Melt Rate Furnace (MRF). This dry fed tool can be used to quickly determine relative melt rates for a large number of candidate frit compositions and lead to a selection for further testing. Simulated Sludge Receipt and Adjustment Tank (SRAT) product was made according to the most recent SB5 sludge projections and a series of tests were conducted with frits that covered a range of boron and alkali ratios. Several frits with relatively large projected operating windows indicated melt rates that would not severely impact production. As seen with previous MRF testing, increasing the boron concentration had positive impacts on melt rate on the SB5 system. However, there appears to be maximum values for both boron and sodium above which the there is a negative effect on melt rate. Based on these data and compositional trends, Frit 418 and a specially designed frit (Frit 550) have been selected for additional melt rate testing. Frit 418 and Frit 550 will be run in the Slurry Fed Melt Rate Furnace (SMRF), which is capable of distinguishing rheological properties not detected by the MRF. Frit 418 will be used initially for SB5 processing in DWPF (given its robustness to compositional uncertainty). The Frit 418-SB5 system will provide a baseline from which potential melt rate advantages of Frit 550 can be gauged. The data from SMRF testing will be used to determine whether Frit 550 should be recommended for implementation in DWPF.

  11. Identifying conditions for inducible protein production in E. coli: combining a fed-batch and multiple induction approach

    Directory of Open Access Journals (Sweden)

    Choi Young J

    2006-08-01

    Full Text Available Abstract Background In the interest of generating large amounts of recombinant protein, inducible systems have been studied to maximize both the growth of the culture and the production of foreign proteins. Even though thermo-inducible systems were developed in the late 1970's, the number of studies that focus on strategies for the implementation at bioreactor scale is limited. In this work, the bacteriophage lambda PL promoter is once again investigated as an inducible element but for the production of green fluorescent protein (GFP. Culture temperature, induction point, induction duration and number of inductions were considered as factors to maximize GFP production in a 20-L bioreactor. Results It was found that cultures carried out at 37°C resulted in a growth-associated production of GFP without the need of an induction at 42°C. Specific production was similar to what was achieved when separating the growth and production phases. Shake flask cultures were used to screen for desirable operating conditions. It was found that multiple inductions increased the production of GFP. Induction decreased the growth rate and substrate yield coefficients; therefore, two time domains (before and after induction having different kinetic parameters were created to fit a model to the data collected. Conclusion Based on two batch runs and the simulation of culture dynamics, a pre-defined feeding and induction strategy was developed to increase the volumetric yield of a temperature regulated expression system and was successfully implemented in a 20-L bioreactor. An overall cell density of 5.95 g DW l-1 was achieved without detriment to the cell specific production of GFP; however, the production of GFP was underestimated in the simulations due to a significant contribution of non-growth associated product formation under limiting nutrient conditions.

  12. Corporate culture

    OpenAIRE

    Stoklasa, Pavel

    2010-01-01

    The theme of the bachelor's thesis is corporate culture, that is currently becoming a very important part of every company. In the theoretical part provides views of the individual authors on this issue. Here are also explained important concepts related to this topic. In particular, the elements of corporate culture, corporate culture change and determinants, that affect it. Furthermore, the theoretical part describes the most famous typology of corporate cultures international authors. The ...

  13. Safety culture

    Energy Technology Data Exchange (ETDEWEB)

    Keen, L.J. [Canadian Nuclear Safety Commission, Ottawa, Ontario (Canada)

    2003-07-01

    Safety culture has become a topic of increasing interest for industry and regulators as issues are raised on safety problems around the world. The keys to safety culture are organizational effectiveness, effective communications, organizational learning, and a culture that encourages the identification and resolution of safety issues. The necessity of a strong safety culture places an onus on all of us to continually question whether the safety measures already in place are sufficient, and are being applied. (author)

  14. Handling Culture

    NARCIS (Netherlands)

    Nispen tot Pannerden, P.J.M. van

    2011-01-01

    The article indicates how companies may prepare for and deal with cultural differences. Because the research base is still rather limited an overall perspective may not be realised. After discussing definitions and concepts of culture, as well as values, cultural differences between states are discu

  15. Culture Clubs.

    Science.gov (United States)

    Gersten, Bridget Fitzgerald

    1998-01-01

    One way to break down barriers and promote understanding among English-as-a-Second-Language (ESL) and mainstream students is to establish culture clubs. Culture clubs involve frequent exchange of information about social, academic, and cultural topics in extracurricular settings. They are a critical component of ESL programs. The article explains…

  16. Transient and Stationary Losses in a Finite-Buffer Queue with Batch Arrivals

    Directory of Open Access Journals (Sweden)

    Andrzej Chydzinski

    2012-01-01

    Full Text Available We present an analysis of the number of losses, caused by the buffer overflows, in a finite-buffer queue with batch arrivals and autocorrelated interarrival times. Using the batch Markovian arrival process, the formulas for the average number of losses in a finite time interval and the stationary loss ratio are shown. In addition, several numerical examples are presented, including illustrations of the dependence of the number of losses on the average batch size, buffer size, system load, autocorrelation structure, and time.

  17. Design and construction of a batch oven for investigation of industrial continuous baking processes

    DEFF Research Database (Denmark)

    Stenby Andresen, Mette; Risum, Jørgen; Adler-Nissen, Jens

    2013-01-01

    A new batch oven has been constructed to mimic industrial convection tunnel ovens for research and development of continuous baking processes. The process parameters (air flow, air temperature, air humidity, height of baking area and the baking band velocity) are therefore highly controllable...... of the baking was documented over a range of temperatures (160C to 190C). Practical Applications The purpose of this paper is to describe a new specially designed pilot scale batch oven. The batch oven is designed and constructed to imitate the baking processes in continuous tunnel ovens with forced convection...

  18. 40 CFR Table 2 to Subpart Ffff of... - Emission Limits and Work Practice Standards for Batch Process Vents

    Science.gov (United States)

    2010-07-01

    ... Standards for Batch Process Vents 2 Table 2 to Subpart FFFF of Part 63 Protection of Environment...—Emission Limits and Work Practice Standards for Batch Process Vents As required in § 63.2460, you must meet... process vents: For each . . . Then you must . . . And you must . . . 1. Process with Group 1 batch...

  19. Cultural Rights and Cultural Diversity

    Institute of Scientific and Technical Information of China (English)

    WANG SIXIN

    2011-01-01

    @@ Culture is a very big concept, big enough almost to comprise all the activities of human beings and the tangible and intangible results caused by human activities.Therefore, it is very difficult to define culture in a few words.

  20. Cultural tourism and tourism cultures

    DEFF Research Database (Denmark)

    Ooi, Can-Seng

    Presenting a comprehensive and dynamic understanding of cultural tourism, this volume examines cultural mediators and how they help tourists appreciate foreign cultures. It also shows how tourism experiences are strategically crafted by mediators, the complexity of the mediation process, and how...... various products are mediated differently. A number of different products are investigated, including destination brand identities, "living" cultures and everyday life, art and history. The author illustrates his arguments by comparing the tourism strategies of Copenhagen and Singapore, and demonstrates...

  1. Succinic acid production by Actinobacillus succinogenes from batch fermentation of mixed sugars.

    Science.gov (United States)

    Almqvist, Henrik; Pateraki, Chrysanthi; Alexandri, Maria; Koutinas, Apostolis; Lidén, Gunnar

    2016-08-01

    Succinic acid production from the monosaccharides xylose, arabinose, glucose, mannose and galactose was studied using the bacterium Actinobacillus succinogenes. In Duran bottle cultures, containing 10 g/L of each of sugar, succinic acid was produced from all sugars except for galactose. The highest succinate yield, 0.56 g/g, was obtained with glucose, whereas the succinate yield was 0.42, 0.38 and 0.44 g/g for xylose, mannose and arabinose, respectively. The specific succinate productivity was 0.7 g/g h for glucose, but below 0.2 g/g h for the other sugars. Batch bioreactor fermentations were carried out using a sugar mixture of the five sugars giving a total concentration of 50 g/L, mimicking the distribution of sugars in spent sulfite liquor (SSL) from Eucalyptus which is rich in xylose. In this mixture, an almost complete conversion of all sugars (except galactose) was achieved resulting in a final succinate concentration of 21.8-26.8 g/L and a total yield of 0.59-0.68 g/g. There was evidence of co-consumption of glucose and xylose, whereas mannose was consumed after glucose. The main by-products were acetate 0.14-0.20 g/g and formate 0.08-0.13 g/g. NADH balance calculations suggested that NADH required for succinate production was not met solely from formate and acetate production, but other means of NADH production was necessary. Results from mixed sugar fermentations were verified using SSL as substrate resulting in a succinate yield of 0.60 g/g. In addition, it was found that CO2 sparging could replace carbonate supply in the form of MgCO3 without affecting the succinate yield. PMID:27255975

  2. miRNA profiling of high, low and non-producing CHO cells during biphasic fed-batch cultivation reveals process relevant targets for host cell engineering.

    Science.gov (United States)

    Stiefel, Fabian; Fischer, Simon; Sczyrba, Alexander; Otte, Kerstin; Hesse, Friedemann

    2016-05-10

    Fed-batch cultivation of recombinant Chinese hamster ovary (CHO) cell lines is one of the most widely used production modes for commercial manufacturing of recombinant protein therapeutics. Furthermore, fed-batch cultivations are often conducted as biphasic processes where the culture temperature is decreased to maximize volumetric product yields. However, it remains to be elucidated which intracellular regulatory elements actually control the observed pro-productive phenotypes. Recently, several studies have revealed microRNAs (miRNAs) to be important molecular switches of cell phenotypes. In this study, we analyzed miRNA profiles of two different recombinant CHO cell lines (high and low producer), and compared them to a non-producing CHO DG44 host cell line during fed-batch cultivation at 37°C versus a temperature shift to 30°C. Taking advantage of next-generation sequencing combined with cluster, correlation and differential expression analyses, we could identify 89 different miRNAs, which were differentially expressed in the different cell lines and cultivation phases. Functional validation experiments using 19 validated target miRNAs confirmed that these miRNAs indeed induced changes in process relevant phenotypes. Furthermore, computational miRNA target prediction combined with functional clustering identified putative target genes and cellular pathways, which might be regulated by these miRNAs. This study systematically identified novel target miRNAs during different phases and conditions of a biphasic fed-batch production process and functionally evaluated their potential for host cell engineering. PMID:27002234

  3. Aerobic Granulation in Sequencing Batch Reactor (SBR Treating Saline Wastewater

    Directory of Open Access Journals (Sweden)

    Ensieh Taheri

    2012-04-01

    Full Text Available Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background and Objectives: Aerobic sludge granulation is an advanced phenomenonin which its mechanisms have not been understood. Granulation can be a promising and novel biological wastewater treatment technology to eliminate organic and inorganic materials in future. High salinity is a parameter which leads to plasmolisatian and reduction of the cell activity. This could be a problem for biological treatment of the saline wastewater. Aerobic granule was formed and investigated during this study. Materials and Methods: This study is an intervention study on the treatment of wastewater with 500-10000 mg/L concentration of NaCl by sequencing batch reactor. Asynthesized wastewater including nutrient required for microorganism's growth was prepared. Input and output pH and EC were measured. Range of pH and DO varied between 7-8, and 2-5 mg/L, respectively. SEM technology was used to identify graduals properties.Results: In terms of color, granules divided into two groups of light brown and black. Granule ranged in 3-7mm with the sediment velocity of 0.9-1.35 m/s and density of 32-60 g/L.Properties of granules were varied. Filamentous bacteria and fungi were dominant in some granules. However non filamentous bacteria were dominant in others. EDX analysis indicated the presence of Ca and PO4.Conclusion: Granules with non filamentous bacterial were compact and settled faster. Presence of different concentrations of salinity leaded to plasmolysis of the bacterial cells and increased concentrations of EPS  in the system as a result  of which granulation accelerated. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso

  4. Characteristics of anoxic phosphors removal in sequence batch reactor

    Institute of Scientific and Technical Information of China (English)

    WANG Ya-yi; PAN Mian-li; Yan Min; PENG Yong-zhen; WANG Shu-ying

    2007-01-01

    The characteristics of anaerobic phosphorus release and anoxic phosphorus uptake was investigated in sequencing batch reactors using denitrifying phosphorus removing bacteria (DPB) sludge. The lab-scale experiments were accomplished under conditions of various nitrite concentrations (5.5, 9.5, and 15 mg/L) and mixed liquor suspended solids (MLSS) (1844, 3231, and 6730 mg/L). The results obtained confirmed that nitrite, MLSS, and pH were key factors, which had a significant impact on anaerobic phosphorus release and anoxic phosphorus uptake in the biological phosphorous removal process. The nitrites were able to successfully act as electron acceptors for phosphorous uptake at a limited concentration between 5.5 and 9.5 mg/L. The denitrification and dephosphorous were inhibited when the nitrite concentration reached 15 mg/L. This observation indicated that the nitrite would not inhibit phosphorus uptake before it exceeded a threshold concentration. It was assumed that an increase of MLSS concentration from 1844 mg/L to 6730 mg/L led to the increase of denitrification and anoxic P-uptake rate. On the contrary, the average P uptake/N denitrifying reduced from 2.10 to 1.57 mg PO43--P/mg NO3--N. Therefore, it could be concluded that increasing MLSS of the DEPHANOX system might shorten the reaction time of phosphorus release and anoxic phosphorus uptake. However, excessive MLSS might reduce the specific denitrifying rate. Meanwhile, a rapid pH increase occurred at the beginning of the anoxic conditions as a result of denitrification and anoxic phosphate uptake. Anaerobic P release rate increased with an increase in pH. Moreover, when pH exceeded a relatively high value of 8.0, the dissolved P concentration decreased in the liquid phase, because of chemical precipitation. This observation suggested that pH should be strictly controlled below 8.0 to avoid chemical precipitation if the biological denitrifying phosphorus removal capability is to be studied accurately.

  5. SLUDGE BATCH 5 VARIABILITY STUDY WITH FRIT 418

    Energy Technology Data Exchange (ETDEWEB)

    Raszewski, F; Tommy Edwards, T; David Peeler, D

    2008-09-29

    The Defense Waste Processing Facility (DWPF) is preparing to initiate processing Sludge Batch 5 (SB5) in early FY 2009. In support of the upcoming processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frit 418 as a transitional frit to initiate processing of SB5. This recommendation was based on the results of assessments on the compositional projections for SB5 available at that time from both the Liquid Waste Organization (LWO) and SRNL (using a model-based approach). To support qualification of the Frit 418-SB5 system, SRNL executed a variability study to assess the acceptability of the Frit 418-SB5 glasses with respect to durability and the applicability of the current durability models. Twenty one glasses were selected for the variability study based on the available SB5 projections primarily spanning a waste loading (WL) range of 25-37%. In order to account for the addition of caustic to Tank 40, which occurred in July 2008, 3 wt% Na2O was added to the original Tank 40 heel projections. The addition of the Actinide Removal Process (ARP) stream to the blend composition was also included. Two of the glasses were fabricated at 25% and 28% WL in order to challenge the homogeneity constraint of the Product Composition Control System (PCCS) for SB5 coupled operations. These twenty one glasses were fabricated and characterized using chemical composition analysis, X-ray Diffraction (XRD) and the Product Consistency Test (PCT). The results of this study indicate that Frit 418 is a viable option for sludge-only and coupled operations. The addition of ARP did not have any negative impacts on the acceptability and predictability of the variability study glasses. Based on the measured PCT response, all of the glasses were acceptable as compared to the Environmental Assessment (EA) reference glass regardless of the thermal history and were also predictable using the current PCCS model for durability. The homogeneity constraint can

  6. Batch Cooling Crystallization of Potassium Sulphate from Water Solution

    Directory of Open Access Journals (Sweden)

    Kalšan, M.

    2009-12-01

    Full Text Available Batch cooling crystallization, at the rotation speed of 700 min–1, of an aqueous solution of a potassium sulphate has been investigated on a laboratory scale. The effect of hydrodynamics conditions on the crystallization process were investigated by using different type of impellers. Two types of impellers were investigated; the four-pitched blade impeller which generates axi-al flow and the six-blades Rusthon turbine which generates radial flow. The experiments were performed at four different linear cooling rates in the range from 8-20 °C h–1 for both types of impeller.The influence of the cooling rates on the metastable zone width, the crystallization kinetics and the granulometric properties of the obtained crystals were investigated. The experimental data show that higher cooling rate expands the metastable zone for all the types of impeller (Fig. 2 and influences the crystal size distribution (Fig. 7 and Fig. 8.At low cooling rates, supersaturation was kept at a constant value for a longer period. It resulted in improved conditions for mass transfer and the crystals grew. Bigger crystals were obtained at lower cooling rates (Fig. 7.It is stated that radial flow (Rusthon turbine is particularly inappropriate for the nucleation process, and for crystallization. Nucleation started at a lower temperature and higher supersaturation (Fig. 3. These conditions resulted in a high nucleation’s rate and large number of nucleation centres.Also, the obtained crystals settled on the wall of the reactor, baffles and stirrer. A great part of the obtained crystals was agglomerated. The nucleation order, n and coefficient of nucleation, kn were determined for different cooling rates (Fig. 5a. The nucleation order is higher at radial flow (nucleation started at higher supersaturation. The relation between the rate of concentration drop in a solution and supersaturation has beenapproximated with a power low equation (Fig. 5b. For the used impellers

  7. The second batch of RE export quota in 2009 released/Brief News

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ In accordance with"Regulation on Import and Export of Commodities of the People's Republic of China",the Ministry of Commerce released the second batch of RE export quota of common trade in 2009 on June 29.

  8. A cellular automata model for simulating fed-batch penicillin fermentation process

    Institute of Scientific and Technical Information of China (English)

    Yu Naigong; Ruan Xiaogang

    2006-01-01

    A cellular automata model to simulate penicillin fed-batch fermentation process(CAPFM)was established in this study,based on a morphologically structured dynamic penicillin production model,that is in turn based on the growth mechanism of penicillin producing microorganisms and the characteristics of penicillin fed-batch fermentation.CAPFM uses the three-dimensional cellular automata as a growth space,and a Moore-type neighborhood as the cellular neighborhood.The transition roles of CAPFM are designed based on mechanical and structural kinetic models of penicillin batch-fed fermentation processes.Every cell of CAPFM represents a single or specific number of penicillin producing microorganisms,and has various state.The simulation experimental results show that CAPFM replicates the evolutionary behavior of penicillin batch-fed fermentation processes described by the structured penicillin production kinetic model accordingly.

  9. A Novel Operation Policy for Dilute Component Separation Quasi-batch Distillation

    Institute of Scientific and Technical Information of China (English)

    罗祎青; 袁希钢; 杨祖杰; 刘春江

    2005-01-01

    A new operation policy--quasi-batch distillation for recovering infinitesimal amounts species existing in a mixture is presented. In quasi-batch distillation operation, feed is introduced with a constant flow rate onto the feed stage of the column, and the flow rate of the distillate is the same as that of the feed, whereas the bottom product is withdrawn periodically. The behavior of quasi-batch distillation is simulated and analyzed through an example on heavy water separation. Comparing with continuous or batch distillation, the new operation policy is more reliable and efficient to achieve higher recovery of dilute component. This is especially suitable for separating small amount of precious species from large amount of raw material.

  10. Enhanced methane production via repeated batch bioaugmentation pattern of enriched microbial consortia.

    Science.gov (United States)

    Yang, Zhiman; Guo, Rongbo; Xu, Xiaohui; Wang, Lin; Dai, Meng

    2016-09-01

    Using batch and repeated batch cultivations, this study investigated the effects of bioaugmentation with enriched microbial consortia (named as EMC) on methane production from effluents of hydrogen-producing stage of potato slurry, as well as on the indigenous bacterial community. The results demonstrated that the improved methane production and shift of the indigenous bacterial community structure were dependent on the EMC/sludge ratio and bioaugmentation patterns. The methane yield and production rate in repeated batch bioaugmentation pattern of EMC were, respectively, average 15% and 10% higher than in one-time bioaugmentation pattern of EMC. DNA-sequencing approach showed that the enhanced methane production in the repeated batch bioaugmentation pattern of EMC mainly resulted from the enriched iron-reducing bacteria and the persistence of the introduced Syntrophomonas, which led to a rapid degradation of individual VFAs to methane. The findings contributed to understanding the correlation between the bioaugmentation of microbial consortia, community shift, and methane production.

  11. CONVERTING FROM BATCH TO CONTINUOUS INTENSIFIED PROCESSING IN THE STT? REACTOR

    Science.gov (United States)

    The fluid dynamics, the physical dimensions and characteristics of the reaction zones of continuous process intensification reactors are often quite different from those of the batch reactors they replace. Understanding these differences is critical to the successful transit...

  12. Enhanced methane production via repeated batch bioaugmentation pattern of enriched microbial consortia.

    Science.gov (United States)

    Yang, Zhiman; Guo, Rongbo; Xu, Xiaohui; Wang, Lin; Dai, Meng

    2016-09-01

    Using batch and repeated batch cultivations, this study investigated the effects of bioaugmentation with enriched microbial consortia (named as EMC) on methane production from effluents of hydrogen-producing stage of potato slurry, as well as on the indigenous bacterial community. The results demonstrated that the improved methane production and shift of the indigenous bacterial community structure were dependent on the EMC/sludge ratio and bioaugmentation patterns. The methane yield and production rate in repeated batch bioaugmentation pattern of EMC were, respectively, average 15% and 10% higher than in one-time bioaugmentation pattern of EMC. DNA-sequencing approach showed that the enhanced methane production in the repeated batch bioaugmentation pattern of EMC mainly resulted from the enriched iron-reducing bacteria and the persistence of the introduced Syntrophomonas, which led to a rapid degradation of individual VFAs to methane. The findings contributed to understanding the correlation between the bioaugmentation of microbial consortia, community shift, and methane production. PMID:27262722

  13. UNBOUNDED BATCH SCHEDULING WITH A COMMON DUE WINDOW ON A SINGLE MACHINE

    Institute of Scientific and Technical Information of China (English)

    Hongluan ZHAO; Guojun LI

    2008-01-01

    The common due window scheduling problem with batching on a single machine is dealt with to minimize the total penalty of weighted earliness and tardiness. In this paper it is assumed that a job incurs no penalty as long as it is completed within the common due window. It is the first time for the due window scheduling to be extended to this situation so that jobs can be processed in batches. An unbounded version of batch scheduling is also considered. Hence, jobs, no matter how many there are, can be processed in a batch once the machine is free. For two cases that the location of due window is either a decision variable or a given parameter, polynomial algorithms are proposed based on several optimal properties.

  14. MOFCOM announced supplement to the first batch of 2012 export quotas

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The Ministry of Commerce of China supplemented the first batch of rare earth export quotas, which were assigned to the companies that had passed the inspection of the Ministry of Environmental Protection.

  15. Preparing cellulose nanocrystal/acrylonitrile-butadiene-styrene nanocomposites using the master-batch method.

    Science.gov (United States)

    Ma, Libo; Zhang, Yang; Meng, Yujie; Anusonti-Inthra, Phuriwat; Wang, Siqun

    2015-07-10

    The master-batch method provides a simple way to apply cellulose nanocrystal (CNC) as reinforcement in a hydrophobic matrix. The two-stage process includes making high-CNC content (70 wt%) master batch pellets, then mixing acrylonitrile-butadiene-styrene (ABS) and maleic anhydride grafted polyethylene with the master batch pellets to prepare the ABS/CNC nanocomposite in extruder. SEM image indicates that self-assembled CNC nanosheets disperse evenly throughout the polymer matrix. The improved mechanical properties shown in tensile and DMA tests reveal that the CNC combines well with the ABS. TGA results show that the thermal degradation temperature of CNC in the master batch increases because of the protection of the ABS coating. This approach not only improves the dispersion ability and the thermal stability of CNC, but it is also applicable to use with other hydrophobic thermoplastics in industrial scale production. PMID:25857992

  16. Data Driven Modeling for Monitoring and Control of Industrial Fed-Batch Cultivations

    DEFF Research Database (Denmark)

    Bonné, Dennis; Alvarez, María Antonieta; Jørgensen, Sten Bay

    2014-01-01

    A systematic methodology for development of a set of discrete-time sequence models for batch control based on historical and online operating data is presented and investigated experimentally. The modeling is based on the two independent characteristic time dimensions of batch processing, being...... convergence of iterative learning control is combined with the closed-loop performance of model predictive control to form an optimal controller aiming to ensure reliable and reproducible operation of the batch process. This learning model predictive controller may also be used for optimizing control through...... optimization of the bioreactor operations model. The modeling and preliminary control performance is demonstrated on an industrial fed-batch protein cultivation production process. The presented methods lend themselves directly for application as Process Analytical Technologies....

  17. Quality of rolled barley flakes as affected by batch of grain and processing technique.

    Science.gov (United States)

    Sundberg, B; Abrahamsson, L; Aman, P

    1994-02-01

    Rolled barely flakes were prepared from three different batches of grain by pearling, steaming and rolling. Autoclaved and malted barleys from the three batches were also processed in the same way. Analysis of the nine products showed that both batch of barley and process had significant effects on chemical composition and viscosity. Puddings were prepared from the products and mechanical consistency, juiciness and grain consistency were graded on both newly prepared and heated puddings by a sensory taste panel. Batch of barley had no effect on mechanical consistency but significant effects on juiciness and grain consistency. Type of processing had significant effect on all three parameters for both newly prepared and heated puddings. PMID:8153065

  18. 40 CFR 1065.170 - Batch sampling for gaseous and PM constituents.

    Science.gov (United States)

    2010-07-01

    ...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.170 Batch sampling...-through support bonded to the back and has an overall thickness of 40 ±20 µm. An inert polymer ring may...

  19. OPTIMAL FEED STRATEGY FOR FED-BATCH GLYCEROL FERMENTATION DETERMINED BY MAXIMUM PRINCIPLE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    1 IntroductionGlycerol fed-batch fermentation is attractive tocommercial application since it can control theglucose concentration by changing the feed rate andget a high glycerol yield, therefore it is essential todevelop an optimal glucose feed strategy. For mostof fed-batch fermentation, optimization of feed ratewas based on Pontryagin's maximum principle [if.Since the term of feed rate appears linearly in theHamiltonian, the optimal feed rate profile usuallyconsists of ba,lg-bang intervals and singular ...

  20. The functionalization of carbon nanotubes using a batch oscillatory flow reactor

    OpenAIRE

    Melendi, Sonia; Bonyadi, S; Castell, P.; Martinez, M.T.; Mackley, M.R.

    2012-01-01

    This paper describes an efficient method for the functionalizing of multi-walled carbon nanotubes (MWCNT) using oscillatory flow mixing (OFM). A 3. l batch oscillatory flow reactor (OFR) was designed and constructed for pilot scale functionalization of MWCNT in order to potentially improve their compatibility within a thermoplastic polyphenylene sulphide (PPS) matrix. The OFM batch reactor consisted of a jacketed cylindrical vessel with a vertical axial oscillator that contained a series of b...

  1. STUDY ON MAXIMUM SPECIFIC SLUDGE ACIVITY OF DIFFERENT ANAEROBIC GRANULAR SLUDGE BY BATCH TESTS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The maximum specific sludge activity of granular sludge from large-scale UASB, IC and Biobed anaerobic reactors were investigated by batch tests. The limitation factors related to maximum specific sludge activity (diffusion, substrate sort, substrate concentration and granular size) were studied. The general principle and procedure for the precise measurement of maximum specific sludge activity were suggested. The potential capacity of loading rate of the IC and Biobed anaerobic reactors were analyzed and compared by use of the batch tests results.

  2. INVESTIGATION OF INTERMITTENT CHLORINATION SYSTEM IN BIOLOGICAL EXCESS SLUDGE REDUCTION BY SEQUENCING BATCH REACTORS

    OpenAIRE

    A. Takdastan ، N. Mehrdadi ، A. A. Azimi ، A. Torabian ، G. Nabi Bidhendi

    2009-01-01

    The excessive biological sludge production is one of the disadvantages of aerobic wastewater treatment processes such as sequencing batch reactors. To solve the problem of excess sludge production, oxidizing some of the sludge by chlorine, thus reducing the biomass coefficient as well as the sewage sludge disposal may be a suitable idea. In this study, two sequencing batch reactors, each with 20 L volume and controlled by on-line system were used. After providing the steady state conditions i...

  3. Stratified randomization controls better for batch effects in 450K methylation analysis: A cautionary tale

    OpenAIRE

    Buhule, Olive D.; Minster, Ryan L.; Nicola L. Hawley; Mario eMedvedovic; Guangyun eSun; Satupaitea eViali; Ranjan eDeka; Stephen T McGarvey; Weeks, Daniel E.

    2014-01-01

    Background: Batch effects in DNA methylation microarray experiments can lead to spurious results if not properly handled during the plating of samples. Methods: Two pilot studies examining the association of DNA methylation patterns across the genome with obesity in Samoan men were investigated for chip- and row-specific batch effects. For each study, the DNA of 46 obese men and 46 lean men were assayed using Illumina's Infinium HumanMethylation450 BeadChip. In the first study (Sample One),...

  4. Stratified randomization controls better for batch effects in 450K methylation analysis: a cautionary tale

    OpenAIRE

    Buhule, Olive D.; Minster, Ryan L.; Nicola L. Hawley; Medvedovic, Mario; SUN, GUANGYUN; Viali, Satupaitea; Deka, Ranjan; Stephen T McGarvey; Weeks, Daniel E.

    2014-01-01

    Background: Batch effects in DNA methylation microarray experiments can lead to spurious results if not properly handled during the plating of samples. Methods: Two pilot studies examining the association of DNA methylation patterns across the genome with obesity in Samoan men were investigated for chip- and row-specific batch effects. For each study, the DNA of 46 obese men and 46 lean men were assayed using Illumina's Infinium HumanMethylation450 BeadChip. In the first study (Sample One), s...

  5. IMPROVING ENERGY EFFICIENCY OF SILICON CARBIDE CERAMICS PRODUCTION BY BATCH REGULATION

    Directory of Open Access Journals (Sweden)

    Dmitriy Zhukov

    2015-09-01

    Full Text Available The article discusses an energy-efficient method for producing SiC-based composites via doping with oxide eutectic compositions and batch granulometry regulation. The influence of batch granulometry on physico-mechanical properties of ceramics is studied, and fractions ratio is determined allowing us to obtain a dense material with improved strength and fracture toughness. Such ceramics shows excellent mechanical behavior and holds much promise as a structural and armor material.

  6. Initial Sulfate Solubility Study for Sludge Batch 4 (SB4)

    Energy Technology Data Exchange (ETDEWEB)

    Lorier, T

    2005-04-01

    The objective of this task is to provide the Defense Waste Processing Facility (DWPF) of the Savannah River Site (SRS) with an assessment of the viability of using the current 0.6 wt% SO{sub 4}{sup =} limit (in glass) and/or the possibility of increasing the SO{sub 4}{sup =} solubility limit to account for anticipated sulfur concentrations in Sludge Batch 4 (SB4). The 0.6 wt% SO{sub 4}{sup =} limit was implemented for processing of Frit 418-Sludge Batch 3 (SB3) to avoid the formation of sulfate inclusions in the glass and/or the formation of a molten sulfate-rich phase on the melt pool in the DWPF melter. The presence of such a phase on the surface of the melt pool increases corrosion rates of melter components, enhances the potential for steam excursions in a slurry-fed waste glass melter, and creates the potential for undesirable current paths that could deplete energy delivered to the melter due to the electrical conductivity of the molten salt layer. This suite of sulfate-solubility tests began by testing the 1200-canister, 2nd transfer case for SB4 (as defined by Lilliston and Shah, 2004)--based on this being the most conservative (having the highest predicted viscosity when coupled with specific frits, it could potentially have the greatest impact on SO{sub 4}{sup =} solubility) blending scenario of SB4 with the heel of SB3 for SO{sub 4}{sup =} solubility. Frits 320 and 418 were tested with SB4 and the tests indicated that at the current SO{sub 4}{sup =} limit (in glass) and the tested waste loadings (30% and 40%), neither Frit 320 nor Frit 418 could be utilized with SB4 (for the 1200-canister, 2nd transfer case composition originally provided). More specifically, SO{sub 4}{sup =} was observed on the surface with the SB4 composition and Frit 320 at 40% waste loading (WL) and 0.6 wt% SO{sub 4}{sup =}, and with Frit 418 at 30% and 40% WL and 0.5 wt% SO{sub 4}{sup =}. As alternative frits were being developed--Frits 447, 448, and 449, that contained CaO and/or V

  7. SULFATE SOLUBILITY LIMIT VERIFICATION FOR DWPF SLUDGE BATCH 7B

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.

    2011-10-03

    The objective of this study was to determine a sulfate solubility limit in glass for Sludge Batch 7b (SB7b). The SB7b composition projection provided by Savannah River Remediation (SRR) on May 25, 2011 was used as the basis for formulating glass compositions to determine the sulfate limit. Additions of Na{sub 2}O to the projected sludge composition were made by the Savannah River National Laboratory (SRNL) due to uncertainty in the final concentration of Na{sub 2}O for SB7b, which is dependent on washing effectiveness and the potential need to add NaOH to ensure an acceptable projected operating window. Additions of 4, 6, and 8 wt % Na{sub 2}O were made to the nominal May 25, 2011 composition projection. An updated SB7b composition projection was received from SRR on August 4, 2011. Due to compositional similarities, no additional experimental work using the August 4, 2011 compositions was considered to be necessary for this study. Both Frit 418 and Frit 702 were included in this study. The targeted sulfate (SO{sub 4}{sup 2-}) concentrations of the study glasses were selected within the range of 0.6 to 0.9 wt % in glass. A total of 52 glass compositions were selected based on the compositional variables of Na{sub 2}O addition, Actinide Removal Process (ARP) stream addition, waste loading, frit composition, and sulfate concentration. The glasses were batched, melted, and characterized following SRNL procedures. Visual observations were recorded for each glass after it cooled and used as in indicator of sulfur retention. Representative samples of each of the glasses fabricated were subjected to chemical analysis to determine whether the targeted compositions were met, as well as to determine the quantity of sulfate that was retained after melting. In general, the measured composition data showed that there were only minor issues in meeting the targeted compositions for the study glasses, and the measured sulfate concentrations for each study glass were within 10% of

  8. Analysis and modelling of the energy consumption of chemical batch plants

    Energy Technology Data Exchange (ETDEWEB)

    Bieler, P.S.

    2004-07-01

    This report for the Swiss Federal Office of Energy (SFOE) describes two different approaches for the energy analysis and modelling of chemical batch plants. A top-down model consisting of a linear equation based on the specific energy consumption per ton of production output and the base consumption of the plant is postulated. The model is shown to be applicable to single and multi-product batches for batch plants with constant production mix and multi-purpose batch plants in which only similar chemicals are produced. For multipurpose batch plants with highly varying production processes and changing production mix, the top-down model produced inaccurate results. A bottom-up model is postulated for such plants. The results obtained are discussed that show that the electricity consumption for infrastructure equipment was significant and responsible for about 50% of total electricity consumption. The specific energy consumption for the different buildings was related to the degree of automation and the production processes. Analyses of the results of modelling are presented. More detailed analyses of the energy consumption of this apparatus group show that about 30 to 40% of steam energy is lost and thus a large potential for optimisation exists. Various potentials for making savings, ranging from elimination of reflux conditions to the development of a new heating/cooling-system for a generic batch reactor, are identified.

  9. Model Integrasi Penjadwalan Produksi Batch dan Penjadwalan Perawatan dengan Kendala Due Date

    Directory of Open Access Journals (Sweden)

    Zahedi .

    2014-01-01

    Full Text Available This paper discusses the integration model of batch production and preventive maintenance scheduling on a single machine producing an item to be delivered at a common due date. The machine is a deteriorating machine that requires preventive maintenance to ensure the availability of the machine at a desired service level. Decision variables of the model are the number of preventive maintenances, the schedule, length of production runs, as well as the number of batches, batch sizes and the production schedule of the resulting batches for each production run. The objective function of the model is to minimize the total cost consisting of inventory costs during parts processing, setup cost and cost of preventive maintenance. The results show three important points: First, the sequence of optimal batches always follows the SPT (short processing time. Second, variation of preventive maintenance unit cost does not influence the sequence of batches. Third, the first production run length from production starting time is smaller than the next production run length and this pattern continues until the due date. When in process inventory unit cost is increased, the pattern will continue until a specified cost limit, and beyond the limit the pattern will change to be the opposite pattern.

  10. An LMI Method to Robust Iterative Learning Fault-tolerant Guaranteed Cost Control for Batch Processes

    Institute of Scientific and Technical Information of China (English)

    WANG Limin; CHEN Xi; GAO Furong

    2013-01-01

    Based on an equivalent two-dimensional Fornasini-Marchsini model for a batch process in industry,a closed-loop robust iterative learning fault-tolerant guaranteed cost control scheme is proposed for batch processes with actuator failures.This paper introduces relevant concepts of the fault-tolerant guaranteed cost control and formulates the robust iterative learning reliable guaranteed cost controller (ILRGCC).A significant advantage is that the proposed ILRGCC design method can be used for on-line optimization against batch-to-batch process uncertainties to realize robust tracking of set-point trajectory in time and batch-to-batch sequences.For the convenience of implementation,only measured output errors of current and previous cycles are used to design a synthetic controller for iterative learning control,consisting of dynamic output feedback plus feed-forward control.The proposed controller can not only guarantee the closed-loop convergency along time and cycle sequences but also satisfy the H∞ performance level and a cost function with upper bounds for all admissible uncertainties and any actuator failures.Sufficient conditions for the controller solution are derived in terms of linear matrix inequalities (LMIs),and design procedures,which formulate a convex optimization problem with LMI constraints,are presented.An example of injection molding is given to illustrate the effectiveness and advantages of the ILRGCC design approach.

  11. On-line Batch Process Monitoring and Diagnosing Based on Fisher Discriminant Analysis

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xu; SHAO Hui-he

    2006-01-01

    A new on-line batch process monitoring and diagnosing approach based on Fisher discriminant analysis (FDA) was proposed. This method does not need to predict the future observations of variables, so it is more sensitive to fault detection and stronger implement for monitoring. In order to improve the monitoring performance,the variables trajectories of batch process are separated into several blocks. The key to the proposed approach for on-line monitoring is to calculate the distance of block data that project to low-dimension Fisher space between new batch and reference batch. Comparing the distance with the predefine threshold, it can be considered whether the batch process is normal or abnormal. Fault diagnosis is performed based on the weights in fault direction calculated by FDA. The proposed method was applied to the simulation model of fed-batch penicillin fermentation and the results were compared with those obtained using MPCA. The simulation results clearly show that the on-line monitoring method based on FDA is more efficient than the MPCA.

  12. An order-picking operations system for managing the batching activities in a warehouse

    Science.gov (United States)

    Lam, Cathy H. Y.; Choy, K. L.; Ho, G. T. S.; Lee, C. K. M.

    2014-06-01

    Nowadays, customer orders with high product variety in small quantities are often received and requested for timely delivery. However, the order-picking process is a labour-intensive and costly activity to handle those small orders separately. In such cases, small orders are often grouped into batches so that two or more orders can be served at once to increase the picking efficiency and thus reduce the travel distance. In this paper, an order-picking operations system (OPOS) is proposed to assist the formulation of an order-picking plan and batch-handling sequence. The study integrates a mathematical model and fuzzy logic technique to divide the receiving orders into batches and prioritise the batch-handling sequence for picking, respectively. Through the proposed system, the order-picking process can be managed as batches with common picking locations to minimise the travel distance, and the batch-picking sequence can be determined as well. To demonstrate the use of the system, a case study in a third-party logistics warehouse is presented, and the result shows that both the order-picking activity and labour utilisation can be better organised.

  13. Hydrogenase activity in aged, nonviable Desulfovibrio vulgaris cultures and its significance in anaerobic biocorrosion.

    Science.gov (United States)

    Chatelus, C; Carrier, P; Saignes, P; Libert, M F; Berlier, Y; Lespinat, P A; Fauque, G; Legall, J

    1987-07-01

    Batch cultures of Desulfovibrio vulgaris stored at 32 degrees C for 10 months have been found to retain 50% of the hydrogenase activity of a 1-day culture. The hydrogenase found in old cultures needs reducing conditions for its activation. Viable cell counts are negative after 6 months, showing that the hydrogenase activity does not depend on the presence of viable cells. These observations are of importance in the understanding of anaerobic biocorrosion of metals caused by depolarization phenomena.

  14. Spatial Culture

    DEFF Research Database (Denmark)

    Reeh, Henrik

    2012-01-01

    of Humani-ties, University of Copenhagen, have been exploring urbanity and aesthetics from the viewpoint of their own generation. Some twenty graduates contribute to the present volume which has been entitled Spatial Culture in order to indicate a common denominator of their MA theses from the years 2002......Spatial Culture – A Humanities Perspective Abstract of introductory essay by Henrik Reeh Secured by alliances between socio-political development and cultural practices, a new field of humanistic studies in spatial culture has developed since the 1990s. To focus on links between urban culture...... and modern society is, however, an intellectual practice which has a much longer history. Already in the 1980s, the debate on the modern and the postmodern cited Paris and Los Angeles as spatio-cultural illustrations of these major philosophical concepts. Earlier, in the history of critical studies, the work...

  15. Cultural diversity

    OpenAIRE

    Raghavan, Raghu

    2011-01-01

    The concept of cultural diversity has emerged as an influential one having impact on multiple policy and legal instruments especially following the adoption of the UNESCO Convention on the Protection and Promotion of the Diversity of Cultural Expressions in 2005. The discussions on its appropriate implementation are however profoundly fragmented and often laden with political considerations. The present brief paper offers some thoughts on the meaning of cultural diversity and its implementati...

  16. Culture Shock

    Institute of Scientific and Technical Information of China (English)

    宋文玲

    2004-01-01

    Specialists say that it is not easy to get used to life in a new culture.“Culture shock”is the term these specialists use when talking about the feelings that people have in a new environment.There are three stages of culture shock,say the specialists.In the first stage,the newcomers like their new environment,Then when the fresh experience

  17. Skin or nail culture

    Science.gov (United States)

    Mucosal culture; Culture - skin; Culture - mucosal; Nail culture; Culture - fingernail; Fingernail culture ... There, it is placed in a special dish (culture). It is then watched to see if bacteria, ...

  18. An Empirical State Error Covariance Matrix for Batch State Estimation

    Science.gov (United States)

    Frisbee, Joseph H., Jr.

    2011-01-01

    state estimate, regardless as to the source of the uncertainty. Also, in its most straight forward form, the technique only requires supplemental calculations to be added to existing batch algorithms. The generation of this direct, empirical form of the state error covariance matrix is independent of the dimensionality of the observations. Mixed degrees of freedom for an observation set are allowed. As is the case with any simple, empirical sample variance problems, the presented approach offers an opportunity (at least in the case of weighted least squares) to investigate confidence interval estimates for the error covariance matrix elements. The diagonal or variance terms of the error covariance matrix have a particularly simple form to associate with either a multiple degree of freedom chi-square distribution (more approximate) or with a gamma distribution (less approximate). The off diagonal or covariance terms of the matrix are less clear in their statistical behavior. However, the off diagonal covariance matrix elements still lend themselves to standard confidence interval error analysis. The distributional forms associated with the off diagonal terms are more varied and, perhaps, more approximate than those associated with the diagonal terms. Using a simple weighted least squares sample problem, results obtained through use of the proposed technique are presented. The example consists of a simple, two observer, triangulation problem with range only measurements. Variations of this problem reflect an ideal case (perfect knowledge of the range errors) and a mismodeled case (incorrect knowledge of the range errors).

  19. Effects of Culture Conditions on Poly(β-Hydroxybutyric Acid) Production by Haloferax mediterranei

    OpenAIRE

    Lillo, Jose Garcia; Rodriguez-Valera, Francisco

    1990-01-01

    The halobacterium Haloferax mediterranei accumulates poly(β-hydroxybutyrate) (PHB) as intracellular granules. The conditions for PHB production in batch and continuous cultures have been studied and optimized. Phosphate limitation is essential for PHB accumulation in large quantities. Glucose and starch are the best carbon sources. With 2% starch, 0.00375% KH2PO4, and 0.2% NH4Cl in batch culture, a production of ca. 6 g of PHB per liter was reached, being 60% of the total biomass dry weight, ...

  20. OPTIMIZING BATCH REKEYING INTERVAL FOR SECURE GROUP COMMUNICATION BASED ON QUEUING MODEL

    Directory of Open Access Journals (Sweden)

    A. Vasanthi

    2014-01-01

    Full Text Available Rapid growth of Internet spawns many group oriented multicast applications like Internet pay TV, news dissemination and stock quote system. The fortes of these applications are the support of dynamic, scalable group membership and group members are geographically divergent. As members of the group move in and out, an imperative cryptographic rekeying model should be applied to preserve the confidentiality of the group. A symmetric key called as session key is employed to defend the group communication data during transit. Forward and backward secrecy is attained by updating the session key for every change in group membership. Depends on the application immediate rekeying or batch rekeying can be used employed. The problem with the batch rekeying algorithm is to determine the pertinent batch size and the optimal time for rekeying process. The main aim is to propose a mathematical model based on queuing theory principles by considering the request for rekeying as Poisson process, rekeying service as an exponential distribution. The performance of the proposed model is analyzed using Java based simulator. By varying the arrival rate and rekeying service rate the optimal batch size can be attained. The optimal rekeying interval improves the performance of the group when the group membership grows dynamically. Reduces the long waiting time of the rekeying requests and find the best batch size for the rekeying. Proposed mathematical model analyses the various control parameters for batch rekeying and locates the best values for the batch size and interval time using the M/M/1/K model queues.

  1. Dose and batch-dependent hepatobiliary toxicity of 10 nm silver nanoparticles

    Directory of Open Access Journals (Sweden)

    Marcella De Maglie

    2015-07-01

    Full Text Available Silver nanoparticles (AgNPs are widely used because of their antimicrobial properties in medical devices and in a variety of consumer products. The extensive use of AgNPs raises concerns about their potential toxicity, although it is still difficult to draw definite conclusions about their toxicity based on published data. Our preliminary studies performed to compare the effect of the AgNPs size (10-40-100 nm on toxicity, demonstrated that the smallest AgNPs determine the most severe toxicological effects. In order to best investigate the impact of physicochemical characteristics of 10 nm AgNPs on toxicity, we compare three different batches of 10 nm AgNPs slightly different in size distribution (Batch A: 8.8±1.7 nm; Batch B: 9.4±1.7 nm; Batch C: 10.0±1.8 nm. Mice were intravenously treated with two doses (5 and 10 mg/kg of the 3 AgNPs. 24 hours after the treatment, mice were euthanized and underwent complete necropsy. Tissues were collected for histopathological examination and total silver content was determined in tissues by inductively coupled plasma mass spectrometry (ICP-MS. All batches induced severe hepatobiliary lesions, i.e. marked hepatocellular necrosis and massive hemorrhage of the gall bladder. The toxicity was dose-dependent and interestingly, the toxic effects were more severe in mice treated with batches A and B that contained smaller AgNPs. Since the total silver mass concentration was similar, the observed batch-dependent toxicity suggest that even subtle differences in size may contribute to relevant changes in the toxicological outcomes, confirming the fundamental involvement of physicochemical features with respect to toxicity.

  2. Manuscript Cultures

    DEFF Research Database (Denmark)

    What do Mesoamerica, Greece, Byzantium, Island, Chad, Ethiopia, India, Tibet, China and Japan have in common? Like many other cultures of the world, they share a particular form of cultural heritage: ancient handwritten documents. In 2007, scholars from some20 countries around the world gathered...

  3. Cultural citizenship

    Directory of Open Access Journals (Sweden)

    Toby Miller

    2011-12-01

    Full Text Available Cultural citizenship is a concept whose time has come. Following on from political citizenship--the right to reside and to vote--and economic citizenship--the right to thrive and prosper--it insists on a right to communication and to the representation of cultural difference.

  4. Cultural citizenship

    OpenAIRE

    Toby Miller

    2011-01-01

    Cultural citizenship is a concept whose time has come. Following on from political citizenship--the right to reside and to vote--and economic citizenship--the right to thrive and prosper--it insists on a right to communication and to the representation of cultural difference.

  5. Culture Stories

    DEFF Research Database (Denmark)

    Jensen, Ole B.

    2007-01-01

    by certain representations and embedded in certain norms and values. The analytical framework is applied on a case of cultural urban branding. The case is the harbour front in Aalborg, Denmark where a number of flagship architecture projects and cultural institutions are being planned. It is shown how...

  6. CULTURAL TOURISM

    Directory of Open Access Journals (Sweden)

    Dana POP

    2016-07-01

    Full Text Available In this paper we will try to analyse the cultural tourism. We will start by referring to the complex concepts of tourism and culture and to the synergies existing between them. We will define cultural tourism and present its appearance and evolution as well as its importance as a modern form of tourism. We will present the various types of cultural tourism with their characteristics and the specific features of cultural tourists according to their interests. We will also mention that there are advantages and disadvantages for any kind of tourism depending on the position – local communities, companies or tourists. For the future we will refer to the new partnership between UNWTO and UNESCO.

  7. High-level secretory expression of human procarboxypeptidase B by Fed-Batch cultivation of Pichia pastoris and its partial characterization.

    Science.gov (United States)

    Kim, Mi-Jin; Kim, Sang-Hyuk; Lee, Jae Hyung; Seo, Jin-Ho; Lee, Jong-Hwan; Kim, Jong-Hyun; Kim, Yeon-Hee; Nam, Soo-Wan

    2008-12-01

    The procpb gene encoding human procarboxypeptidase B (proCPB, GeneBank access code AJ224866) was cloned and its Pichia expression plasmid, pPIC9alpha/hproCPB (9.2 kb), was constructed, in which procpb was under the control of the AOX1 promoter and connected to the downstream of the mating factor alpha-1 (MFalpha1) signal sequence. The plasmid was linearized by digestion with SacI, and integrated into the genome of P. pastoris strain GS115. By culturing of Pichia transformant on methanol medium, the human proCPB was successfully expressed and secreted into the culture supernatant. Moreover, Western blot analysis of the extracellular proteins showed proCPB bands clearly at a molecular mass of 45 kDa, confirming the expression of proCPB with its right size. The CPB activity reached about 3.5 U/ml and 12.7 U/ml in the flask and fermentor batch cultures of Pichia transformant, respectively. No CPB enzyme activity was found in the intracellular fraction. When the fedbatch cultivation was performed with methanol and glycerol mixture as a feeding medium, the extracellular CPB activity was increased to 42.0 U/ml, which corresponds to a 3.3-fold higher level of CPB activity than that of batch culture. The Km and kcat values of recombinant human CPB enzyme for hippuryl-L-Arg as a substrate were estimated to be 0.16mM and 11.93 sec-1, respectively. PMID:19131697

  8. Algal Feedback and Removal Efficiency in a Sequencing Batch Reactor Algae Process (SBAR to Treat the Antibiotic Cefradine.

    Directory of Open Access Journals (Sweden)

    Jianqiu Chen

    Full Text Available Many previous studies focused on the removal capability for contaminants when the algae grown in an unexposed, unpolluted environment and ignored whether the feedback of algae to the toxic stress influenced the removal capability in a subsequent treatment batch. The present research investigated and compared algal feedback and removal efficiency in a sequencing batch reactor algae process (SBAR to remove cefradine. Three varied pollution load conditions (10, 30 and 60 mg/L were considered. Compared with the algal characteristics in the first treatment batch at 10 and 30 mg/L, higher algal growth inhibition rates were observed in the second treatment batch (11.23% to 20.81%. In contrast, algae produced more photosynthetic pigments in response to cefradine in the second treatment batch. A better removal efficiency (76.02% was obtained during 96 h when the alga treated the antibiotic at 60 mg/L in the first treatment batch and at 30 mg/L in the second treatment batch. Additionally, the removal rate per unit algal density was also improved when the alga treated the antibiotic at 30 or 60 mg/L in the first treatment batch, respectively and at 30 mg/L in the second treatment batch. Our result indicated that the green algae were also able to adapt to varied pollution loads in different treatment batches.

  9. Enrichment of high ammonia tolerant methanogenic culture

    DEFF Research Database (Denmark)

    Fotidis, Ioannis; Karakashev, Dimitar Borisov; Proietti, Nicolas;

    of the current study was to isolate and identify methanogenic cultures tolerant to high ammonia concentrations. A mixed methanogenic population was stepwise exposed to ammonia concentrations (1 to 9.26 g NH4+-N L-1) during an enrichment process with successive batch cultivations. The methanogenic population...... was derived from a full scale biogas reactor (Hashøj, Denmark), fed with 75% animal manure and 25% food industries organic waste. Basal anaerobic medium was used for the enrichment along with sodium acetate (1 g HAc L-1) as a carbon source. Fluorescence insitu hybridization (FISH) was used to determine...... microbial community composition. The outcome of the enrichment process was a mesophilic aceticlastic methanogenic enriched culture able to withstand high ammonia loads and utilize acetate and form methane stoichiometrically. FISH analysis showed that the methanogens of the enriched culture belonged...

  10. SLUDGE BATCH 6/TANK 40 SIMULANT CHEMICAL PROCESS CELL SIMULATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, David

    2010-04-28

    Phase III simulant flowsheet testing was completed using the latest composition estimates for SB6/Tank 40 feed to DWPF. The goals of the testing were to determine reasonable operating conditions and assumptions for the startup of SB6 processing in the DWPF. Testing covered the region from 102-159% of the current DWPF stoichiometric acid equation. Nitrite ion concentration was reduced to 90 mg/kg in the SRAT product of the lowest acid run. The 159% acid run reached 60% of the DWPF Sludge Receipt and Adjustment Tank (SRAT) limit of 0.65 lb H2/hr, and then sporadically exceeded the DWPF Slurry Mix Evaporator (SME) limit of 0.223 lb H2/hr. Hydrogen generation rates peaked at 112% of the SME limit, but higher than targeted wt% total solids levels may have been partially responsible for rates seen. A stoichiometric factor of 120% met both objectives. A processing window for SB6 exists from 102% to something close to 159% based on the simulant results. An initial recommendation for SB6 processing is at 115-120% of the current DWPF stoichiometric acid equation. The addition of simulated Actinide Removal Process (ARP) and Modular Caustic Side Solvent Extraction Unit (MCU) streams to the SRAT cycle had no apparent impact on the preferred stoichiometric factor. Hydrogen generation occurred continuously after acid addition in three of the four tests. The three runs at 120%, 118.4% with ARP/MCU, and 159% stoichiometry were all still producing around 0.1 lb hydrogen/hr at DWPF scale after 36 hours of boiling in the SRAT. The 120% acid run reached 23% of the SRAT limit and 37% of the SME limit. Conversely, nitrous oxide generation was subdued compared to previous sludge batches, staying below 29 lb/hr in all four tests or about a fourth as much as in comparable SB4 testing. Two processing issues, identified during SB6 Phase II flowsheet testing and qualification simulant testing, were monitored during Phase III. Mercury material balance closure was impacted by acid stoichiometry

  11. Time requirements in closed and open batch distillation arrangements for separation of a binary mixture

    Directory of Open Access Journals (Sweden)

    Zhao Shuo

    2014-12-01

    Full Text Available Batch time requirements are provided for the separation of binary zeotropic mixtures in two different multivessel columns (with and without vapor bypass, a non-cyclic two-vessel column and a regular batch column based on dynamic simulations. The first three columns are operated as closed (total reflux systems and the regular batch column is operated as an open (partial reflux system. We analyze the effects of feed composition, relative volatility and product specification on the time requirements. The multivessel arrangements perform better than the regular batch column, which requires from 4.00 to 34.67% more time to complete a given separation. The elimination of the vapor bypass in the multivessel column is impractical though it has a positive effect on the batch time requirements. Thus, the multivessel column, with the vapor stream bypassing the intermediate vessel, is proposed as the best candidate for a binary zeotropic mixture with low concentration of light component, low relative volatility and high product purity demand. Furthermore, an experimental multivessel column with vapor bypass is built and the corresponding experiments verify the simulations.

  12. Comparison of batch and column tests for the elution of artificial turf system components.

    Science.gov (United States)

    Krüger, O; Kalbe, U; Berger, W; Nordhauβ, K; Christoph, G; Walzel, H-P

    2012-12-18

    Synthetic athletic tracks and turf areas for outdoor sporting grounds may release contaminants due to the chemical composition of some components. A primary example is that of zinc from reused scrap tires (main constituent, styrene butadiene rubber, SBR), which might be harmful to the environment. Thus, methods for the risk assessment of those materials are required. Laboratory leaching methods like batch and column tests are widely used to examine the soil-groundwater pathway. We tested several components for artificial sporting grounds with batch tests at a liquid to solid (LS) ratio of 2 L/kg and column tests with an LS up to 26.5 L/kg. We found a higher zinc release in the batch test eluates for all granules, ranging from 15% higher to 687% higher versus data from column tests for SBR granules. Accompanying parameters, especially the very high turbidity of one ethylene propylene diene monomer rubber (EPDM) or thermoplastic elastomer (TPE) eluates, reflect the stronger mechanical stress of batch testing. This indicates that batch test procedures might not be suitable for the risk assessment of synthetic sporting ground components. Column tests, on the other hand, represent field conditions more closely and allow for determination of time-dependent contaminants release. PMID:23153171

  13. Stage 2 Process Performance Qualification (PPQ): a Scientific Approach to Determine the Number of PPQ Batches.

    Science.gov (United States)

    Pazhayattil, Ajay; Alsmeyer, Daniel; Chen, Shu; Hye, Maksuda; Ingram, Marzena; Sanghvi, Pradeep

    2016-08-01

    The approach documented in this article reviews data from earlier process validation lifecycle stages with a described statistical model to provide the "best estimate" on the number of process performance qualification (PPQ) batches that should generate sufficient information to make a scientific and risk-based decision on product robustness. This approach is based upon estimation of a statistical confidence from the current product knowledge (Stage 1), historical variability for similar products/processes (batch-to-batch), and label claim specifications such as strength. The analysis is to determine the confidence level with the measurements of the product quality attributes and to compare them with the specifications. The projected minimum number of PPQ batches required will vary depending on the product, process understanding, and attributes, which are critical input parameters for the current statistical model. This new approach considers the critical finished product CQAs (assay, dissolution, and content uniformity), primarily because assay/content uniformity and dissolution as well as strength are the components of the label claim. The key CQAs determine the number of PPQ batches. This approach will ensure that sufficient scientific data is generated to demonstrate process robustness as desired by the 2011 FDA guidance.

  14. Cultural History and Cultural Materialism.

    Science.gov (United States)

    Berman, Ronald

    1990-01-01

    Historicism critiques cultural history and cultural materialism as a methodology for literary analysis. Questions the finality of interpretation, how original values change, and whether dramatic history implies actual history. Using Shakespearean plays, analyzes the power and politics of a play in relation to its audience; posits that cultural…

  15. Large-scale production of endotoxin-free plasmids for transient expression in mammalian cell culture.

    Science.gov (United States)

    Rozkov, Aleksei; Larsson, Bert; Gillström, Stefan; Björnestedt, Robert; Schmidt, Stefan R

    2008-02-15

    Transient expression of recombinant proteins in mammalian cell culture in a 100-L scale requires a large quantity of plasmid that is very labour intensive to achieve with shake flask cultures and commercially available plasmid purification kits. In this paper we describe a process for plasmid production in 100-mg scale. The fermentation is carried out in a 4-L fed-batch culture with a minimal medium. The detection of the end of batch and triggering the exponential (0.1 h(-1)) feed profile was unattended and controlled by Multi-fermenter Control System. A restricted specific growth rate in fed-batch culture increased the specific plasmid yield compared to batch cultures with minimal and rich media. This together with high biomass concentration (68-107 g L(-1) wet weight) achieves high volumetric yields of plasmid (95-277 mg L(-1) depending on the construct). The purification process consisted of alkaline lysis, lysate clarification and ultrafiltration, two-phase extraction with Triton X-114 for endotoxin removal, anion-exchange chromatography as a polishing step, ultrafiltration and sterile filtration. Both fermentation and purification processes were used without optimisation for production of four plasmids yielding from 39 to 163 mg of plasmids with endotoxin content of 2.5 EU mg(-1) or less. PMID:17680665

  16. Culture School

    Institute of Scientific and Technical Information of China (English)

    MATTHEW LIM

    2008-01-01

    @@ Until recently, employees posted abroad would, if they were lucky, receive some limited language training before they relocated. How they would cope with living in a completely new culture when they arrived was left up to them to figure out.

  17. Blood culture

    Science.gov (United States)

    Culture - blood ... A blood sample is needed . The site where blood will be drawn is first cleaned with an antiseptic such ... organism from the skin getting into (contaminating) the blood sample and causing a false-positive result (see ...

  18. Cultural Spectrum

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Exorbitant Performance Fees ProhibitedThe Ministry of Culture has taken measures todiscourage performance artists from charging excessively for their stage appearances. According to the ministry, payment for performers and ticket prices must be in line with average con-

  19. Yangshao Culture

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Yangshao culture was born in the Neolithic Age. In 1921, archaeologists unearthed a number of chipped stone implements such as knives and axes; bone objects and everyday ceramic items. Thus Yangshao Village and its matriarchal society have

  20. LifeRaft: Data-Driven, Batch Processing for the Exploration of Scientific Databases

    CERN Document Server

    Wang, Xiaodan; Malik, Tanu

    2009-01-01

    Workloads that comb through vast amounts of data are gaining importance in the sciences. These workloads consist of "needle in a haystack" queries that are long running and data intensive so that query throughput limits performance. To maximize throughput for data-intensive queries, we put forth LifeRaft: a query processing system that batches queries with overlapping data requirements. Rather than scheduling queries in arrival order, LifeRaft executes queries concurrently against an ordering of the data that maximizes data sharing among queries. This decreases I/O and increases cache utility. However, such batch processing can increase query response time by starving interactive workloads. LifeRaft addresses starvation using techniques inspired by head scheduling in disk drives. Depending upon the workload saturation and queuing times, the system adaptively and incrementally trades-off processing queries in arrival order and data-driven batch processing. Evaluating LifeRaft in the SkyQuery federation of astr...

  1. Fuzzy logic feedback control for fed-batch enzymatic hydrolysis of lignocellulosic biomass.

    Science.gov (United States)

    Tai, Chao; Voltan, Diego S; Keshwani, Deepak R; Meyer, George E; Kuhar, Pankaj S

    2016-06-01

    A fuzzy logic feedback control system was developed for process monitoring and feeding control in fed-batch enzymatic hydrolysis of a lignocellulosic biomass, dilute acid-pretreated corn stover. Digested glucose from hydrolysis reaction was assigned as input while doser feeding time and speed of pretreated biomass were responses from fuzzy logic control system. Membership functions for these three variables and rule-base were created based on batch hydrolysis data. The system response was first tested in LabVIEW environment then the performance was evaluated through real-time hydrolysis reaction. The feeding operations were determined timely by fuzzy logic control system and efficient responses were shown to plateau phases during hydrolysis. Feeding of proper amount of cellulose and maintaining solids content was well balanced. Fuzzy logic proved to be a robust and effective online feeding control tool for fed-batch enzymatic hydrolysis.

  2. Oxidative stability of frozen mackerel batches ― A multivariate data analysis approach

    DEFF Research Database (Denmark)

    Helbo Ekgreen, M.; Frosch, Stina; Baron, Caroline Pascale

    2011-01-01

    Mackerel are usually caught in the autumn and often frozen either on board the fishing vessel or soon after landing. Due to the seasonality of the catching period, mackerel can be stored frozen for a long time period before entering the production chain. However, frozen storage of fatty fish...... such as mackerel can lead to a significant loss in fish quality primarily due to oxidation of the long chain omega-3 fatty acids. These quality changes results in significant loss for the fish processing industries and in fish with poor eating quality. In order to investigate batch-to-batch variation due...... to different catching methods and different freezing procedures 6 batches of frozen mackerel were obtained from the local producer of caned mackerel. Fish were processed as soon as possible after landing i.e. headed, gutted and individually frozen at the industry. However, one of the catch was abused...

  3. Modeling and Optimization for Short-term Scheduling of Multipurpose Batch Plants

    Institute of Scientific and Technical Information of China (English)

    陈国辉; 鄢烈祥; 史彬

    2014-01-01

    In the past two decades, short-term scheduling of multipurpose batch plants has received significant at-tention. Most scheduling problems are modeled using either state-task-network or resource-task-network (RTN) process representation. In this paper, an improved mixed integer linear programming model for short-term schedul-ing of multipurpose batch plants under maximization of profit is proposed based on RTN representation and unit-specific events. To solve the model, a hybrid algorithm based on line-up competition algorithm and linear pro-gramming is presented. The proposed model and hybrid algorithm are applied to two benchmark examples in lit-erature. The simulation results show that the proposed model and hybrid algorithm are effective for short-term scheduling of multipurpose batch plants.

  4. Operation parameters of a small scale batch distillation column for hydrous ethanol fuel (HEF production

    Directory of Open Access Journals (Sweden)

    F. D. Mayer

    2015-04-01

    Full Text Available Batch distillation applied to hydrous ethanol fuel (HEF production on a small scale still requires operating conditions that ensure optimal top product quality and productivity. The aim of this study is to statistically validate a batch still through the employment of response surface methodology (RSM. Operational and productivity parameters were formulated in order to guarantee quality compliance with the legal requirements for the top product concentration, besides providing support information to control the production of HEF on a small scale. The reboiler control and dephlegmator temperatures maintained within the range of 97.5 to 99.5°C and 60 to 70°C, respectively, combined with a variable reflux ratio, was satisfactory in obtaining a top product concentration, in accordance with legal regulations, as well as high productivity. The results of this study may contribute to the assembly of a simple and low-cost batch distillation control system.

  5. Design of batch operations: Systematic methodology for generation and analysis of sustainable alternatives

    DEFF Research Database (Denmark)

    Carvalho, Ana; Matos, Henrique A.; Gani, Rafiqul

    2010-01-01

    The objective of this paper is to present a new methodology that is able to generate, screen and identify sustainable alternatives to continuous chemical processes as well as processes operating in the batch mode. The methodology generates the sustainable (design) alternatives by locating...... processes are described, highlighting the main differences between them. Through two case studies, the application of the methodology, to obtain sustainable design alternatives for batch plants, is highlighted....... the operational, environmental, economical and safety related problems inherent in the process (batch or continuous). Alternatives that are more sustainable, compared to a reference, are generated and evaluated by addressing one or more of the identified problems. A decomposition technique as well as a set...

  6. Optimal Feed Rate Control of Escherichia coli Fed-batch Fermentation

    Directory of Open Access Journals (Sweden)

    Olympia Roeva

    2005-04-01

    Full Text Available In this paper an optimal control algorithm for E. coli fed-batch fermentation has been developed. A simple material balance model is used to describe the E. coli fermentation process. The optimal feed rate control of a primary metabolite process is studied and a biomass production is used as an example. An optimization of a fed-batch fermentation process is usually done using the calculus of variations to determine an optimal feed rate profile. In the optimal control literature the problem is formulated as a free final time problem where the control objective is to maximise biomass at the end of the process. The obtained optimal feed rate profile consists of sequences of maximum and minimum feed rates. The obtained results are used for optimization of E. coli fed-batch fermentation and the presented simulations show a good efficiency of the developed optimal feed rate profile.

  7. Waste heat recovery at the glass industry with the intervention of batch and cullet preheating

    Directory of Open Access Journals (Sweden)

    Dolianitis Ioannis

    2016-01-01

    Full Text Available A promising option to reduce the specific energy consumption and CO2 emissions at a conventional natural gas fired container glass furnace deals with the advanced utilization of the exhaust gases downstream the air regenerators by means of batch and cullet preheating. A 3-dimensional computational model that simulates this process using mass and heat transfer equations inside a preheater has been developed. A case study for an efficient small-sized container glass furnace is presented dealing with the investigation of the impact of different operating and design configurations on specific energy consumption, CO2 emissions, flue gas energy recovery, batch temperature and preheater efficiency. In specific, the effect of various parameters is studied, including the preheater’s dimensions, flue gas temperature, batch moisture content, glass pull, combustion air excess and cullet fraction. Expected energy savings margin is estimated to 12-15%.

  8. Functional Unfold Principal Component Regression Methodology for Analysis of Industrial Batch Process Data

    DEFF Research Database (Denmark)

    Mears, Lisa; Nørregaard, Rasmus; Sin, Gürkan;

    2016-01-01

    process operating at Novozymes A/S. Following the FUPCR methodology, the final product concentration could be predicted with an average prediction error of 7.4%. Multiple iterations of preprocessing were applied by implementing the methodology to identify the best data handling methods for the model......This work proposes a methodology utilizing functional unfold principal component regression (FUPCR), for application to industrial batch process data as a process modeling and optimization tool. The methodology is applied to an industrial fermentation dataset, containing 30 batches of a production....... It is shown that application of functional data analysis and the choice of variance scaling method have the greatest impact on the prediction accuracy. Considering the vast amount of batch process data continuously generated in industry, this methodology can potentially contribute as a tool to identify...

  9. Rescheduling to Minimize Total Completion Time Under a Limit Time Disruption for the Parallel Batch

    Institute of Scientific and Technical Information of China (English)

    XU Xiao-yan; MU Yun-dong; GUO Xiao; HAO Yun

    2015-01-01

    In the rescheduling on a single machine, a set of the original jobs has already been scheduled, in order to make a given objective function is optimal. The decision maker needs to insert the new jobs into the existing schedule without excessively disrupting it. A batching machine is a machine that can handle up to some jobs simultaneously. In this paper, we consider the total completion time under a limit on the sequence disruptions for parallel batching based on rescheduling. For the parallel batching problem based on rescheduling, we research the properties of feasible schedules and optimal schedules on the total completion time under a limit on the maximum time disruptions or total time disruptions, in which the jobs are sequenced in SPT order, and give out the pseudo-polynomial time algorithms on the number of jobs and the processing time of jobs by applying the dynamic programming method.

  10. A Batch Rival Penalized Expectation-Maximization Algorithm for Gaussian Mixture Clustering with Automatic Model Selection

    Directory of Open Access Journals (Sweden)

    Jiechang Wen

    2012-01-01

    Full Text Available Within the learning framework of maximum weighted likelihood (MWL proposed by Cheung, 2004 and 2005, this paper will develop a batch Rival Penalized Expectation-Maximization (RPEM algorithm for density mixture clustering provided that all observations are available before the learning process. Compared to the adaptive RPEM algorithm in Cheung, 2004 and 2005, this batch RPEM need not assign the learning rate analogous to the Expectation-Maximization (EM algorithm (Dempster et al., 1977, but still preserves the capability of automatic model selection. Further, the convergence speed of this batch RPEM is faster than the EM and the adaptive RPEM in general. The experiments show the superior performance of the proposed algorithm on the synthetic data and color image segmentation.

  11. Cultural Imports

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    FOREIGN commodities have flowed into China since the country opened its doors to the outside world. China is an expansive territory with a huge population offering a vast potential consumer market. There are absolutely no limits to the world of culture in China, with Chinese people having access to foreign films, dramas, music and books, all of which have helped to strengthen exchanges between Chinese and Western cultures.

  12. Study of a sequencing batch reactor performance in soft drink wastewater treatment

    Directory of Open Access Journals (Sweden)

    Francisco Javier Cuba Terán

    2009-08-01

    Full Text Available A sequencing batch aerobic reactor in pilot scale was constructed and operated with intermittent aeration in Wastewater Treatment Lab of Faculdade de Ciências e Tecnologia de Unesp at Presidente Prudente city. Research was conducted in order to improve reactor’s performance in organic matter and nitrogen removal by means of the application of different aeration times. In 12 and 14 hours long batch tests, with 6 and 8 hours of aeration, more than 96% of organic matter was removed by the third hour in both cases, in the other hand, nitrification showed 50 and 55% of removal at the end of every cycle. Tough showing nitrate removal, denitrification requires more research to be done in order to obtain more accurate data related with best cycle time for both pollutants removal.Key-words: sequencing batchs, aerobic treatment, industrial wastewater.A sequencing batch aerobic reactor in pilot scale was constructed and operated with intermittent aeration in Wastewater Treatment Lab of Faculdade de Ciências e Tecnologia de Unesp at Presidente Prudente city. Research was conducted in order to improve reactor’s performance in organic matter and nitrogen removal by means of the application of different aeration times. In 12 and 14 hours long batch tests, with 6 and 8 hours of aeration, more than 96% of organic matter was removed by the third hour in both cases, in the other hand, nitrification showed 50 and 55% of removal at the end of every cycle. Tough showing nitrate removal, denitrification requires more research to be done in order to obtain more accurate data related with best cycle time for both pollutants removal.Key-words: sequencing batchs, aerobic treatment, industrial wastewater.

  13. Batching alternatives for Phase I retrieval wastes to be processed in WRAP Module 1

    Energy Technology Data Exchange (ETDEWEB)

    Mayancsik, B.A. [Westinghouse Hanford Co., Richland, WA (United States)

    1994-10-13

    During the next two decades, the transuranic (TRU) waste now stored in the 200 Area burial trenches and storage buildings is to be retrieved, processed in the Waste Receiving and Processing (WRAP) Module 1 facility, and shipped to a final disposal facility. The purpose of this document is to identify the criteria that can be used to batch suspect TRU waste, currently in retrievable storage, for processing through the WRAP Module 1 facility. These criteria are then used to generate a batch plan for Phase 1 Retrieval operations, which will retrieve the waste located in Trench 4C-04 of the 200 West Area burial ground. The reasons for batching wastes for processing in WRAP Module 1 include reducing the exposure of workers and the environment to hazardous material and ionizing radiation; maximizing the efficiency of the retrieval, processing, and disposal processes by reducing costs, time, and space throughout the process; reducing analytical sampling and analysis; and reducing the amount of cleanup and decontamination between process runs. The criteria selected for batching the drums of retrieved waste entering WRAP Module 1 are based on the available records for the wastes sent to storage as well as knowledge of the processes that generated these wastes. The batching criteria identified in this document include the following: waste generator; type of process used to generate or package the waste; physical waste form; content of hazardous/dangerous chemicals in the waste; radiochemical type and quantity of waste; drum weight; and special waste types. These criteria were applied to the waste drums currently stored in Trench 4C-04. At least one batching scheme is shown for each of the criteria listed above.

  14. Stratified randomization controls better for batch effects in 450K methylation analysis: A cautionary tale

    Directory of Open Access Journals (Sweden)

    Olive D. Buhule

    2014-10-01

    Full Text Available Background: Batch effects in DNA methylation microarray experiments can lead to spurious results if not properly handled during the plating of samples. Methods: Two pilot studies examining the association of DNA methylation patterns across the genome with obesity in Samoan men were investigated for chip- and row-specific batch effects. For each study, the DNA of 46 obese men and 46 lean men were assayed using Illumina's Infinium HumanMethylation450 BeadChip. In the first study (Sample One, samples from obese and lean subjects were examined on separate chips. In the second study (Sample Two, the samples were balanced on the chips by lean/obese status, age group, and census region. We used methylumi, watermelon, and limma R packages, as well as ComBat, to analyze the data. Principal component analysis and linear regression were respectively employed to identify the top principal components and to test for their association with the batches and lean/obese status. To identify differentially methylated positions (DMPs between obese and lean males at each locus, we used a moderated t-test.Results: Chip effects were effectively removed from Sample Two but not Sample One. In addition, dramatic differences were observed between the two sets of DMP results. After removing'' batch effects with ComBat, Sample One had 94,191 probes differentially methylated at a q-value threshold of 0.05 while Sample Two had zero differentially methylated probes. The disparate results from Sample One and Sample Two likely arise due to the confounding of lean/obese status with chip and row batch effects.Conclusion: Even the best possible statistical adjustments for batch effects may not completely remove them. Proper study design is vital for guarding against spurious findings due to such effects.

  15. Batching alternatives for Phase I retrieval wastes to be processed in WRAP Module 1

    International Nuclear Information System (INIS)

    During the next two decades, the transuranic (TRU) waste now stored in the 200 Area burial trenches and storage buildings is to be retrieved, processed in the Waste Receiving and Processing (WRAP) Module 1 facility, and shipped to a final disposal facility. The purpose of this document is to identify the criteria that can be used to batch suspect TRU waste, currently in retrievable storage, for processing through the WRAP Module 1 facility. These criteria are then used to generate a batch plan for Phase 1 Retrieval operations, which will retrieve the waste located in Trench 4C-04 of the 200 West Area burial ground. The reasons for batching wastes for processing in WRAP Module 1 include reducing the exposure of workers and the environment to hazardous material and ionizing radiation; maximizing the efficiency of the retrieval, processing, and disposal processes by reducing costs, time, and space throughout the process; reducing analytical sampling and analysis; and reducing the amount of cleanup and decontamination between process runs. The criteria selected for batching the drums of retrieved waste entering WRAP Module 1 are based on the available records for the wastes sent to storage as well as knowledge of the processes that generated these wastes. The batching criteria identified in this document include the following: waste generator; type of process used to generate or package the waste; physical waste form; content of hazardous/dangerous chemicals in the waste; radiochemical type and quantity of waste; drum weight; and special waste types. These criteria were applied to the waste drums currently stored in Trench 4C-04. At least one batching scheme is shown for each of the criteria listed above

  16. Urine culture - catheterized specimen

    Science.gov (United States)

    Culture - urine - catheterized specimen; Urine culture - catheterization; Catheterized urine specimen culture ... urinary tract infections may be found in the culture. This is called a contaminant. You may not ...

  17. Batch sodium borohydride hydrolysis systems: Effect of sudden valve opening on hydrogen generation rate

    OpenAIRE

    M. J. F. Ferreira; Coelho, F; Rangel, C. M.; Pinto, A. M. F. R.

    2012-01-01

    A study was undertaken in order to investigate the potential of hydrogen (H 2) generation by hydrolysis of sodium borohydride solution (10 wt% NaBH 4 and 7 wt% NaOH), in batch reactors, operating at moderate pressures (up to #8764;1.2 MPa), in the presence of a powdered nickel-ruthenium based catalyst, reused between 311 and 316 times, to feed on-demand a proton exchange membrane fuel cell. A different approach to the testing of the performance of the batch NaBH 4 hydrolysis system is explore...

  18. Results of initial analyses of the salt (macro) batch 9 tank 21H qualification samples

    Energy Technology Data Exchange (ETDEWEB)

    Peters, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-10-01

    Savannah River National Laboratory (SRNL) analyzed samples from Tank 21H in support of qualification of Interim Salt Disposition Project (ISDP) Salt (Macro) Batch 9 for processing through the Actinide Removal Process (ARP) and the Modular Caustic-Side Solvent Extraction Unit (MCU). This document reports the initial results of the analyses of samples of Tank 21H. Analysis of the Tank 21H Salt (Macro) Batch 9 composite sample indicates that the material does not display any unusual characteristics or observations, such as floating solids, the presence of large amount of solids, or unusual colors. Further results on the chemistry and other tests will be issued in the future.

  19. Results Of Initial Analyses Of The Salt (Macro) Batch 9 Tank 21H Qualification Samples

    Energy Technology Data Exchange (ETDEWEB)

    Peters, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-10-08

    Savannah River National Laboratory (SRNL) analyzed samples from Tank 21H in support of qualification of Interim Salt Disposition Project (ISDP) Salt (Macro) Batch 9 for processing through the Actinide Removal Process (ARP) and the Modular Caustic-Side Solvent Extraction Unit (MCU). This document reports the initial results of the analyses of samples of Tank 21H. Analysis of the Tank 21H Salt (Macro) Batch 9 composite sample indicates that the material does not display any unusual characteristics. Further results on the chemistry and other tests will be issued in the future.

  20. Sensor combination and chemometric variable selection for online monitoring of Streptomyces coelicolor fed-batch cultivations

    DEFF Research Database (Denmark)

    Ödman, Peter; Johansen, C.L.; Olsson, L.;

    2010-01-01

    -one-batch-out cross-validation, and the best models had root mean square error of cross-validation values of 1.02 g l(-1) biomass and 0.8 g l(-1) total amino acids, respectively. The fluorescence data were also explored by parallel factor analysis. The analysis revealed four spectral profiles present......Fed-batch cultivations of Streptomyces coelicolor, producing the antibiotic actinorhodin, were monitored online by multiwavelength fluorescence spectroscopy and off-gas analysis. Partial least squares (PLS), locally weighted regression, and multilinear PLS (N-PLS) models were built for prediction...

  1. Change in hyphal morphology of Aspergillus Oryzae during fed-batch cultivation

    DEFF Research Database (Denmark)

    Haack, Martin Brian; Olsson, Lisbeth; Hansen, K;

    2006-01-01

    the batch phase from 2.8-2.9 up to 4.0-4.4 mu m. The diameter of the hyphal elements remained constant, around 4 mu m, after the feed was started. However, the diameter of the immediate hyphal tip, where the enzyme secretion is thought to take place, increased dramatically with up to a factor 2.5 during......Industrial enzymes are often produced by filamentous fungi in fed-batch cultivations. During cultivation, the different morphological forms displayed by the fungi have an impact on the overall production. The morphology of a recombinant lipase producing Aspergillus oryzae strain was investigated...

  2. A Combination of Varying Column Pressure and Total Reflux—Total Efflux in Batch Distillation Operation

    Institute of Scientific and Technical Information of China (English)

    ZHANGWeijiang; QUHongmei; 等

    2002-01-01

    A novel operation of batch distillation-combination of varying colum pressure and total reflux-total efflux is studied experimentally. In the operation, the product is accumulated at the top of the column under total reflux and then drained off completely, and the column pressure is varying in the whole process. This process has been industrialized successfully with large profits. The conventional mode of batch distillation is improved by this method effectively: the separation eficiency and the yield of product are increased greatly, the operation time is shortened and the production cost is cut down. Moreover, the amount of condensation water is decreased and the over-high reboiler temperature is lowered.

  3. A Practical SSL Server Performance Improvement Algorithm Based on Batch RSA Decryption

    Institute of Scientific and Technical Information of China (English)

    LI Shi-qun; WU Yong-dong; ZHOU Jian-ying; CHEN Ke-fei

    2008-01-01

    The secure socket layer/ transport layer security(SSL/TLS) handshake protocol uses public key cryptographic algorithms such as RSA for key establishment. Typically, public key cryptographic algorithm is computational intensive due to the modular multiplications. Therefore, SSL/TLS servers often become swamped while performing public key decryptious when the simultaneous requests increase quickly. A batch RSA decryption algorithm was proposed. The novel algorithm provides the reasonable response time and opti-mizes server performance significantly. The decryption speedup is proportional to the batch size b, for instance,the speedup factor is 4, while in Shacham's scheme the acceleration rate is only 2.5 when b=4.

  4. Biodiesel and FAME synthesis assisted by microwaves: Homogeneous batch and flow processes

    Energy Technology Data Exchange (ETDEWEB)

    J. Hernando; P. Leton; M.P. Matia; J.L. Novella; J. Alvarez-Builla [Universidad de Alcala, Madrid (Spain). Planta Piloto de Quimica Fina

    2007-07-15

    Fatty acids methyl esters (FAME) have been prepared under microwave irradiation, using homogeneous catalysis, either in batch or in a flow system. The quality of the biodiesel obtained has been confirmed by GC analysis of the isolated product. While the initial experiments have been performed in a small scale laboratory batch reactor, the best experiment has been straightforward converted into a stop-flow process, by the use of a microwave flow system. Compared with conventional heating methods, the process using microwaves irradiation proved to be a faster method for alcoholysis of triglycerides with methanol, leading to high yields of FAME. Short communication. 19 refs., 2 tabs.

  5. A biochemically structured model for ethanol fermentation by Kluyveromyces marxianus: A batch fermentation and kinetic study

    DEFF Research Database (Denmark)

    Sansonetti, Sascha; Hobley, Timothy John; Calabrò, V.;

    2011-01-01

    Anaerobic batch fermentations of ricotta cheese whey (i.e. containing lactose) were performed under different operating conditions. Ethanol concentrations of ca. 22gL−1 were found from whey containing ca. 44gL−1 lactose, which corresponded to up to 95% of the theoretical ethanol yield within 15h...... ethanol, lactose, biomass and glycerol during batch fermentation could be described within a ca. 6% deviation, as could the yield coefficients for biomass and ethanol produced on lactose. The model structure confirmed that the thermodynamics considerations on the stoichiometry of the system constrain the...... metabolic coefficients within a physically meaningful range thereby providing valuable and reliable insight into fermentation processes....

  6. Kinetics studies of uranium sorption by powdered corn cob in batch and fixed bed system.

    Science.gov (United States)

    Mahmoud, Mohamed A

    2016-01-01

    Sorption of uranium (VI) from aqueous solution onto powdered corn cob has been carried out using batch and fixed-bed technique. The experimental results in batch technique were fitted well with pseudo second-order kinetics model. In the fixed bed technique, Thomas and Bohart-Adams models were evaluated by linear regression analysis for U(VI) uptake in different flow rates, bed heights and initial concentrations. The column experimental data were fitted well with Thomas mode (r (2) = 0.999), but the Bohart-Adams model (r (2) = 0.911), predicted poor performance of fixed-bed column. PMID:26843973

  7. Cell culture for three-dimensional modeling in rotating-wall vessels: an application of simulated microgravity

    Science.gov (United States)

    Schwarz, R. P.; Goodwin, T. J.; Wolf, D. A.

    1992-01-01

    High-density, three-dimensional cell cultures are difficult to grow in vitro. The rotating-wall vessel (RWV) described here has cultured BHK-21 cells to a density of 1.1 X 10(7) cells/ml. Cells on microcarriers were observed to grow with enhanced bridging in this batch culture system. The RWV is a horizontally rotated tissue culture vessel with silicon membrane oxygenation. This design results in a low-turbulence, low-shear cell culture environment with abundant oxygenation. The RWV has the potential to culture a wide variety of normal and neoplastic cells.

  8. A Cultural Sexuality or a Sexual Culture?

    OpenAIRE

    Vandermeersch, Patrick

    1990-01-01

    P. Vandermeersch, A Cultural Sexuality or a Sexual Culture? In: F. VAN DE VIJVER & G. HUTSCHEMAEKERS (ed.), The Investigation of Culture. Current Issues in Cultural Psychology, Tilburg, Tilburg University Press, 1990, 43-58.

  9. Cultural Robotics: The Culture of Robotics and Robotics in Culture

    OpenAIRE

    Hooman Samani; Elham Saadatian; Natalie Pang; Doros Polydorou; Owen Noel Newton Fernando; Ryohei Nakatsu; Jeffrey Tzu Kwan Valino Koh

    2013-01-01

    In this paper, we have investigated the concept of "Cultural Robotics" with regard to the evolution of social into cultural robots in the 21st Century. By defining the concept of culture, the potential development of a culture between humans and robots is explored. Based on the cultural values of the robotics developers, and the learning ability of current robots, cultural attributes in this regard are in the process of being formed, which would define the new concept of cultural robotics. Ac...

  10. Culturally Responsive Teaching: Understanding Disability Culture

    Science.gov (United States)

    Darrow, Alice-Ann

    2013-01-01

    To be culturally responsive teachers, we must first have an understanding of other cultures and how students from these cultures differ from one another. As we consider the many cultures represented in our classrooms, we might also consider students with disabilities as a cultural group. Within any main culture are subgroups differentiated by…

  11. Japanese Shame Culture and American Guilt Culture

    Institute of Scientific and Technical Information of China (English)

    Lu Weijie

    2016-01-01

    Culture is an important factor contributing to the success of intercultural communication. In the east and west, there are many different cultures, among which Japanese shame culture and American guilt culture are two typical ones. Influenced by different cultures, these two countries have different characteristics, which reminds us that in intercultural communication culture should be paid much attention to.

  12. Corecovery of lipids and fermentable sugars from Rhodosporidium toruloides using ionic liquid cosolvents: application of recycle to batch fermentation.

    Science.gov (United States)

    Severa, Godwin; Kumar, Guneet; Cooney, Michael J

    2014-01-01

    This work evaluates the ability of an ionic liquid-methanol cosolvent system to extract lipids and recycle fermentable sugars recovered from oil-bearing Rhodosporidium toruloides grown in batch culture on defined media using glucose and xylose as carbon sources. Growth on the recycled mixed carbon substrate was successful with glucose consumed before xylose and overall cell mass to lipid yields (YP/X ) between 57% and 61% (w/w relative to whole dried cell mass) achieved. Enzymatic hydrolysis of the delipified carbohydrate fraction recovered approximately 9%-11% (w/w) of the whole dried cell mass as fermentable sugars, which were successfully recycled as carbon sources without further purification. In total, up to 70% (w/w) of the whole dried cell mass was recovered as lipids and fermentable sugars and the substrate to lipid yields (YP/S ) was increased from 0.12 to 0.16 g lipid/g carbohydrate consumed, highlighting the promise of this approach to process lipid bearing cell biomass.

  13. Fed-batch anaerobic valorization of slaughterhouse by-products with mesophilic microbial consortia without methane production.

    Science.gov (United States)

    Pessiot, J; Nouaille, R; Jobard, M; Singhania, R R; Bournilhas, A; Christophe, G; Fontanille, P; Peyret, P; Fonty, G; Larroche, C

    2012-07-01

    This work aimed at setting up a fully instrumented, laboratory-scale bioreactor enabling anaerobic valorization of solid substrates through hydrogen and/or volatile fatty acid (VFA) production using mixed microbial populations (consortia). The substrate used was made of meat-based wastes, especially from slaughterhouses, which are becoming available in large amounts as a consequence of the growing constraints for waste disposal from meat industry. A reconstituted microbial mesophilic consortium without Archaebacteria (methanogens), named PBr, was cultivated in a 5-L anaerobic bioreactor on slaughterhouse wastes. The experiments were carried out with sequential fed-batch operations, including liquid medium removal from the bioreactor and addition of fresh substrate. VFAs and nitrogen were the main metabolites observed, while hydrogen accumulation was very low and no methane production was evidenced. After 1,300 h of culture, yields obtained for VFAs reached 0.38 g/g dry matter. Strain composition of the microbial consortium was also characterized using molecular tools (temporal temperature gradient gel electrophoresis and gene sequencing).

  14. Studies on the effect of coal particle size on biodepyritization of high sulfur coal in batch bioreactor

    Directory of Open Access Journals (Sweden)

    Singh Sradhanjali

    2015-03-01

    Full Text Available The moderate thermophilic mix culture bacteria were used to depyritize the Illinois coal of varying particle sizes (-100 μm, 100-200 μm, +200 μm. Mineral libration analysis showed the presence of pyrite along with other minerals in coal. Microbial depyritization of coal was carried out in stirred tank batch reactors in presence of an iron-free 9K medium. The results indicate that microbial depyritization of coal using moderate thermophiles is an efficient process. Moreover, particle size of coal is an important parameter which affects the efficiency of microbial depyritization process. At the end of the experiment, a maximum of 75% pyrite and 66% of pyritic sulphur were removed from the median particle size. The XRD analysis showed the absence of pyrite mineral in the treated coal sample. A good mass balance was also obtained with net loss of mass ranging from 5-9% showing the feasibility of the process for large scale applications.

  15. Genetic variability in a frozen batch of MCF-7 cells invisible in routine authentication affecting cell function.

    Science.gov (United States)

    Kleensang, Andre; Vantangoli, Marguerite M; Odwin-DaCosta, Shelly; Andersen, Melvin E; Boekelheide, Kim; Bouhifd, Mounir; Fornace, Albert J; Li, Heng-Hong; Livi, Carolina B; Madnick, Samantha; Maertens, Alexandra; Rosenberg, Michael; Yager, James D; Zhaog, Liang; Hartung, Thomas

    2016-01-01

    Common recommendations for cell line authentication, annotation and quality control fall short addressing genetic heterogeneity. Within the Human Toxome Project, we demonstrate that there can be marked cellular and phenotypic heterogeneity in a single batch of the human breast adenocarcinoma cell line MCF-7 obtained directly from a cell bank that are invisible with the usual cell authentication by short tandem repeat (STR) markers. STR profiling just fulfills the purpose of authentication testing, which is to detect significant cross-contamination and cell line misidentification. Heterogeneity needs to be examined using additional methods. This heterogeneity can have serious consequences for reproducibility of experiments as shown by morphology, estrogenic growth dose-response, whole genome gene expression and untargeted mass-spectroscopy metabolomics for MCF-7 cells. Using Comparative Genomic Hybridization (CGH), differences were traced back to genetic heterogeneity already in the cells from the original frozen vials from the same ATCC lot, however, STR markers did not differ from ATCC reference for any sample. These findings underscore the need for additional quality assurance in Good Cell Culture Practice and cell characterization, especially using other methods such as CGH to reveal possible genomic heterogeneity and genetic drifts within cell lines. PMID:27456714

  16. Organ culture

    DEFF Research Database (Denmark)

    Alm, Rikard; Edvinsson, Lars; Malmsjö, Malin

    2002-01-01

    BACKGROUND: Endothelium dysfunction is believed to play a role in the development of cardiovascular disease. The aim of the present study was to evaluate the suitability of organ culture as a model for endothelium dysfunction. METHODS: The isometric tension was recorded in isolated segments...... of the rat mesenteric artery branch, before and after organ culture for 20 h. Vasodilatation was expressed as % of preconstriction with U46619. The acetylcholine (ACh) induced nitric oxide (NO) mediated dilatation was studied in the presence of 10 microM indomethacin, 50 nM charybdotoxin and 1 microM apamin....... Endothelium-derived hyperpolarising factor (EDHF) was studied in the presence of 0.1 mM L-NOARG and indomethacin. Prostaglandins were studied in the presence of L-NOARG, charybdotoxin and apamin. RESULTS: The ACh-induced NO and prostaglandin-mediated dilatations decreased significantly during organ culture...

  17. Cultural Resurrection

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    "Who are we?Where are we from?"Humans have been pondering these questions since the day they first came into being.One of the ways we preserve memories of the past is through our cul- tural heritage that has been passed on from generation to genera- tion.Intangible cultural heritage,as well as tangible cultural her- itage,is essential to the continuity of human civilization. Since the United Nations Educational,Scientific and Cultural Organization(UNESCO)unveiled the Masterpieces of the Oral and Intangible Heritage of Humanity in 2001,China has had Kunqu opera,Guqin and its music,the art of Uygur Muqam of Xinjiang and the traditional Mongolian folk song Long Song added to UNESCO’s protection list.It is now one of the coun-

  18. Cultural Usability

    DEFF Research Database (Denmark)

    Shi, Qingxin

    2007-01-01

    Culture has already played an important role in the global market. It not only affects products, but also impacts on usability evaluation methods. This project aims to examine in the established thinking aloud usability evaluation method (TA UEM), how does the evaluator build a supportive...... relationship and communicate effectively with the user in order to find relevant usability problems in culturally localized applications. It includes three parts, pilot study, field study and experiments, to get both qualitative data and quantitative data. From this project, we hope to find an effective way...... to structure our TA UEM methodology to capture or be sensitive towards the mental models and ways of thinking in different cultural groups....

  19. Influence of batch-to-batch reproducibility of Luna C-18(2) packing material, nature of column wall material, and column diameter on the liquid chromatographic analysis of basic analytes

    NARCIS (Netherlands)

    Vervoort, RJM; Ruyter, E; Debets, AJJ; Claessens, HA; Cramers, CA; de Jong, GJ

    2001-01-01

    This paper discusses aspects arising on transferring liquid chromatography (LC) methods developed on conventional size columns to micro LC, i.e. the influence of batch-to-batch reproducibility of packing material, the nature of the column wall material, and the column inner diameter. it was shown th

  20. Selective carboxylate production by controlling hydrogen, carbon dioxide and substrate concentrations in mixed culture fermentation

    NARCIS (Netherlands)

    Arslan, D.; Steinbusch, K.J.J.; Diels, L.; Wever, de H.; Hamelers, H.V.M.; Buisman, C.J.N.

    2013-01-01

    This research demonstrated the selective production of n-butyrate from mixed culture by applying 2 bar carbon dioxide into the headspace of batch fermenters or by increasing the initial substrate concentration. The effect of increasing initial substrate concentration was investigated at 8, 13.5 and