Effects of Co-Substrates and Inorganic Ions on Biodegradation of Oil-Degrading Strains

2011 ◽  
Vol 179-180 ◽  
pp. 781-786 ◽  
Author(s):  
Jian Yang Feng ◽  
Xiao De Zhou
Keyword(s):  
Degradation Rate ◽  
Inorganic Ions ◽  
Polluted Soil ◽  
Single Strain ◽  
Metabolic Characteristics ◽  
Degradation Rates ◽  
Degradation Tests ◽  
Aeration Conditions ◽  
Degradation Ability ◽  
Reaction Bottle

Six strains named SY1 to SY6 were isolated from oil-polluted soil. The degradation tests of oil by our isolates were carried out under still-reaction-bottle-aeration and shaking-aeration conditions. The co-metabolic characteristics of two co-substrates (ethanol and glucose) and inorganic ions on the biodegradation of oil by our isolates were also studied. The results show that oil can be degraded by the six isolates effectively. The degradation ability of strains is enhanced due to co-substrates added. The enhanced roles of glucose are stronger than ethanol to SY1 and SY5; while the enhanced roles of ethanol are stronger than glucose to SY3.And the enhanced roles of glucose and ethanol are similar to SY2, SY4 and SY6. Inorganic ions, such as Ca2 + Fe2 +, Mg2+, etc, could promote the degradation ability of strains and improve the growth of strains. The degradation effects of mixed strains were inferior to that of single strain. After five days, the degradation rate of SY3 was worst, which was 65.7%. In the mixed strains, there were only 11 groups’ degradation rates greater than that of SY3, and other 46 groups’ degradation rates were less than that of SY3.

Research for Biodegradation and Bioaugmentation of Drilling Wastewater

2013 ◽  
Vol 684 ◽  
pp. 226-229
Author(s):  
Feng Xu ◽  
Jin Chuan Gu ◽  
Jin Bao
Keyword(s):  
Activated Sludge ◽  
Degradation Rate ◽  
Orthogonal Experiment ◽  
Impact Resistance ◽  
Single Strain ◽  
Optimal Ratio ◽  
Augmented System ◽  
Activated Sludge System ◽  
Degradation Rates ◽  
Drilling Site

The paper studied the degradation rate of single strain, the microorganisms agent compatibility and the bioaugmentation effects of the activated sludge system. The results showed that 10 strains screened from drilling site were able to degrade drilling wastewater. Confirm the optimal ratio of strains’ compatibility through orthogonal experiment. In augmented experiments, it showed that in the control SBR system with the COD of the effluent was in three different average levels (with two load shock), the COD degradation rates were 21.4%, 22.8% and 6.9%. In the augmented system treated with the same effluent, the degradation rates of augmented system were 64.8%, 62.78% and 66.9% respectively. It showed that the activated sludge was augmented by the mixed cultures which made the system to be more stable and improve impact resistance.

scholarly journals Research on Degradation Characteristics of Nonylphenol in Water by Highly Effective Complex Microorganisms

2018 ◽  
Vol 53 ◽  
pp. 04016
Author(s):  
Juan Ma ◽  
Fang-yan Chen ◽  
Yu-bin Tang ◽  
Xin-gang Wang
Keyword(s):  
Pseudomonas Putida ◽  
Yangtze River ◽  
Degradation Rate ◽  
Volume Ratio ◽  
Morphological Observation ◽  
Bacterial Suspension ◽  
Canal Water ◽  
Form Complex ◽  
Single Strain ◽  
Degrading Bacteria

Aiming at effectively controlling nonylphenol (NP) pollution, three bacterial strains were isolated from activated sludge and landfill leachate, which could grow with nonylphenol as sole carbon and energy source. The three nonylphenol-degrading bacteria isolated were named as WN6, SLY9 and SLY10, respectively. The morphological observation and 16S rDNA identification revealed that the strains belonged to Serratia sp., Klebsiella sp. and Pseudomonas putida, respectively. WN6 and SLY9 contained ALK gene, while WN6 and SLY10 harbored C12O genes. The three strains were combined together to form complex microorganisms ZJF. The ratio of Serratia sp. to Klebsiella sp. to Pseudomonas putida was 2:1:2 (volume ratio of bacterial suspension). Under the conditions that temperature was 30 ℃, pH was 6, inoculation amount was 10% (volume ratio), initial concentration of NP solutions was 20 mg/L, NP degradation rate by ZJF reached 73.82%, compared with any single strain of the three bacteria, NP degradation rate by ZJF increased more than 15% during 6 days. Bioremediation of nonylphenol-polluted the Yangtze River and the Ancient Canal water by ZJF ware simulated. After a 6-day incubation period, the degrading rate of nonylphenol in Ancient Canal water was close to 80%, and the degrading rate of nonylphenol in Yangtze River water was 72.84%.

scholarly journals Nutritional diversity of Brachiaria ruziziensis clones

2018 ◽  
Vol 48 (2) ◽  
Author(s):  
Ellen de Almeida Moreira ◽  
Shirley Motta de Souza ◽  
Alexandre Lima Ferreira ◽  
Thierry Ribeiro Tomich ◽  
José Augusto Gomes Azevêdo ◽  
...  
Keyword(s):  
Degradation Rate ◽  
Neutral Detergent Fiber ◽  
Ruminal Fermentation ◽  
Dry Matter Digestibility ◽  
Brachiaria Ruziziensis ◽  
Hierarchical Grouping ◽  
Degradation Rates ◽  
Main Components ◽  
Lower Contribution

ABSTRACT: The aim of this study was to evaluate the nutritional diversity of Brachiaria ruziziensis clones through chemical composition and in vitro kinetics of ruminal fermentation. Twenty three clones of Brachiaria ruziziensis were used (15, 16, 46, 174, 411, 590, 651, 670, 768, 776, 844, 859, 950, 965, 970, 975, 1067, 1093, 1296, 1765, 1806, 1894 and 1972) and Brachiaria ruziziensis cv. ‘Kennedy’, Brachiaria brizantha cv. ‘Marandu’ and Brachiaria decumbens cv. ‘Basilisk’ as controls within 27 days of harvesting. The experimental design used randomized blocks with 26 treatments (genotypes) and three replications. Evaluation of the nutritional divergence was performed using principal components analysis, based on the following discriminatory variables: in vitro dry matter digestibility (IVDMD), neutral detergent fiber (NDF), lignin, crude protein (CP), degradation rate of non-fibrous carbohydrates (KdNFC) and degradation rate of fibrous carbohydrates (KdFC). The evaluation of the nutritional diversity of Brachiaria genotypes was based on the two main components (IVDMD and NDF), which explains 96.2% of the total variance Variables of lower contribution to the discrimination of the clones were as degradation rates of the fibrous and non-fibrous carbohydrates. In the agglomerative hierarchical grouping analysis, five distinct groups were identified, where V group, formed by clones 46, 768 and 1067 have higher values of IVDMD compared to the other clones.

Diverting electron fluxes towards sulfate reduction using linoleic acid in a mixed anaerobic culturePaper submitted to the Journal of Environmental Engineering and Science.

2010 ◽  
Vol 37 (11) ◽  
pp. 1492-1504
Author(s):  
Mamata Sharma ◽  
Nihar Biswas
Keyword(s):  
Linoleic Acid ◽  
Sulfate Reduction ◽  
Degradation Rate ◽  
Volatile Fatty Acids ◽  
Removal Rate ◽  
Electron Flow ◽  
Methane Formation ◽  
Sulfate Removal ◽  
Degradation Rates ◽  
High Concentrations

Sulfate (1500 mg/L) reduction and glucose (1870 mg/L) degradation was examined in the presence of five varying linoleic acid (LA) levels (100–1000 mg/L) at 37 ± 2 °C and pH 7.0–7.2. The sulfate reduction and methane formation data suggest that LA selectively inhibited methane producing bacteria (MPB). The quantity of sulfate removed increased with increasing LA dosage. Approximately 1375 mg/L (92%) sulfate was removed in cultures fed with high concentrations of LA (1000 mg/L), which was 68% more than that removed in glucose and sulfate controls. The quantity of sulfate removed in cultures fed with 100, 300, 500 and 700 mg/L LA were 62%, 66%, 77%, and 84%, respectively. Initial sulfate degradation rates increased with increasing LA levels in the cultures. High LA levels (1000 mg/L) attributed to approximately a sevenfold increase in the initial sulfate degradation rates compared to cultures containing sulfate plus glucose. The highest initial sulfate removal rate (0.19 µg/(mgVSS min)) was observed in cultures receiving 1000 mg/L LA. Initial glucose degradation rates decreased with increasing LA concentrations. The rates for the cultures receiving 1000 mg/L LA were 2.53 µg/(mgVSS min) while the degradation rate for cultures containing 100 mg/L LA was 5.40 µg/(mgVSS min). Methane formation decreased when sulfate and LA were added. Methane formation was lowest in cultures receiving elevated LA concentrations. The percent electron flow fluxes increased towards sulfidogenesis and decreased towards methanogenesis with increasing LA levels. Less than 0.6% electron flow was diverted to methanogenesis in cultures containing high levels of LA (≥700 mg/L) while ≤ 45% was diverted to sulfidogenesis. Acetate and propionate were the major volatile fatty acids (VFAs) detected during glucose degradation. The amount of sulfate reduced in the cultures receiving only LA or sulfate and no other carbon source was comparable (approximately 10%), which suggests that LA did not contribute to electrons during the course of experiment for sulfate reduction.

Evaluation of the effect of tamping on the track geometry condition: A case study

2016 ◽  
Vol 232 (2) ◽  
pp. 408-420 ◽  
Author(s):  
Iman Soleimanmeigouni ◽  
Alireza Ahmadi ◽  
Iman Arasteh Khouy ◽  
Christophe Letot
Keyword(s):  
Degradation Rate ◽  
Probabilistic Approach ◽  
Dominant Factor ◽  
Model Parameters ◽  
Track Geometry ◽  
Degradation Rates ◽  
Railway Maintenance ◽  
Long Term Prediction

Tamping is one of the major activities undertaken by railway maintenance managers to recover the track geometry condition. Modelling the effectiveness of tamping along with track geometry degradation is essential for long-term prediction of track geometry behaviour. The aim of this study is to analyse the effect of tamping on the different track geometry measurements, i.e. longitudinal level, alignment and cant, based on inspection car records from a part of the Main Western Line in Sweden. To model recovery after tamping, a probabilistic approach is applied. The track geometry condition before tamping was considered as the dominant factor for modelling the model parameters. Correlation analysis was performed to measure the linear relation between the recoveries of the different geometry measures. The results show a moderate correlation between the recovery of the longitudinal level and that of the cant, and a weak correlation between the recovery of the longitudinal level and that of the alignment. Linear regression and Wiener process were also applied to model track geometry degradation and to obtain degradation rates. The effect of tamping on degradation rate was analysed. It was observed that degradation rate increased after tamping.

scholarly journals Photocatalytic Degradation of Monolinuron and Linuron in an Aqueous Suspension of Titanium Dioxide Under Simulated Solar Irradiation

2007 ◽  
Vol 20 (2) ◽  
pp. 163-172 ◽  
Author(s):  
Razika Zouaghi ◽  
Abdennour Zertal ◽  
Bernard David ◽  
Sylvie Guittonneau
Keyword(s):  
Photocatalytic Degradation ◽  
Degradation Rate ◽  
Ph Value ◽  
Degradation Kinetics ◽  
Aqueous Suspension ◽  
Operating Conditions ◽  
Solar Irradiation ◽  
Point Of Zero Charge ◽  
Degradation Rates ◽  
Simulated Solar Irradiation

Abstract The photocatalytic degradation of two phenylurea herbicides, monolinuron (MLN) and linuron (LN), was investigated in an aqueous suspension of TiO2 using simulated solar irradiation. The objective of the study was to compare their photocatalytic reactivity and to assess the influence of various parameters such as initial pesticide concentration, catalyst concentration and photonic flux on the photocatalytic degradation rate of MLN and LN. A comparative study of the photocatalytic degradation kinetics of both herbicides showed that these two compounds have a comparable reactivity with TiO2/simulated sun light. Under the operating conditions of this study, the photocatalytic degradation of MLN and LN followed pseudo first-order decay kinetics. The kobs values indicated an inverse dependence on the initial herbicide concentration and were fitted to the Langmuir-Hinshelwood equation. Photocatalytic degradation rates increased with TiO2 dosage, but overdoses did not necessarily increase the photocatalytic efficiency. The degradation rate of MLN increased with radiant flux until an optimum at 580 W m‑2 was reached and then decreased. Under these conditions, an electron-hole recombination was favored. Finally, the photocatalytic degradation rate depended on pH, where an optimum was found at a pH value close to the pH of the point of zero charge (pH = 6).

scholarly journals Protein degradation during terminal cytodifferentiation. Studies on mammary gland in organ culture

1980 ◽  
Vol 192 (1) ◽  
pp. 311-320 ◽  
Author(s):  
C J Wilde ◽  
N Paskin ◽  
J Saxton ◽  
R J Mayer
Keyword(s):  
Mammary Gland ◽  
Fatty Acid ◽  
Protein Degradation ◽  
Degradation Rate ◽  
Fatty Acid Synthase ◽  
Average Rate ◽  
Cytosol Fraction ◽  
Isotope Method ◽  
Degradation Rates ◽  
Double Isotope

1. In mammary gland explants subjected to experimental manipulation, average rates (during 24 h periods) of degradation of fatty acid synthase, casein and cytosol-fraction proteins were measured by a double-isotope method. Rates of degradation of fatty acid synthase were also computed from measurements of changing enzyme amount and rate of synthesis. 2. During the period of most rapid enzyme accumulation there is a transient decrease in the computed rate of degradation of fatty acid synthase. Removal of hormones produces a rapid increase in the computed rate of degradation of the enzyme. 3. The average rate of degradation of fatty acid synthase measured by the double-isotope method is low in the presence of hormones, and increases on hormone removal. This increase in degradation rate is inhibited by adrenaline and further blocked by insulin. NH4Cl (10 mM) also partially inhibits the increase in protein degradation on hormone removal. 4. The pattern of changes in the average rate of degradation of cytosol-fraction proteins is similar to that for fatty acid synthase alone. There is no relationship between subunit molecular weight and rate of degradation under all experimental conditions. 5. Isotope ratios for resolved cytosol protein mixtures are transformed logarithmically to make the standard deviations an estimate of heterogeneity of degradation rates. By this analysis, in some conditions there appears to be significant measureable heterogeneity of degradation rates. 6. Little degradation of casein is measured in the presence of hormones, but a marked increase in the rate of degradation can be measured when hormones are removed. Whereas at 24-48h NH4Cl (10 mM) has little effect on this enhanced rate of degradation, at 48-72h it causes a large decrease in degradation rate. 7. Results are discussed in terms of a two-component degradation system in mammary gland explants.

Advanced oxidation of methyl tert-butyl ether (MTBE) by UV/TiO2 and H2O2-UV/TiO2 processes

2006 ◽  
Vol 6 (2) ◽  
pp. 77-85 ◽  
Author(s):  
C.-H. Hung
Keyword(s):  
Light Intensity ◽  
Degradation Rate ◽  
Reaction Rate ◽  
Experimental Results ◽  
Methyl Tert Butyl Ether ◽  
H2o2 Concentration ◽  
Pseudo First Order Reaction ◽  
Butyl Ether ◽  
Solution Ph ◽  
Degradation Rates

This study investigated photocatalysis of MTBE via both UV/TiO2 and H2O2-UV/TiO2 processes. Several experimental parameters including pH level, H2O2 concentration, TiO2 dosage and light intensity were investigated. The experimental results demonstrated the degradation of MTBE following a pseudo first-order reaction in both reaction systems. Faster degradation rates were observed in alkaline solution for the UV/TiO2 system, but for the H2O2-UV/TiO2 system, faster degradation rates were detected in acidic solution. More dosage of TiO2 and irradiated light intensity were beneficial for the photocatalysis of MTBE. However, a peak reaction rate was observed at a TiO2 concentration of about 500 mg/L. The experimental results also indicated that the degradation rate of MTBE was enhanced by the addition of H2O2. H2O2 could be a more efficient electron acceptor than oxygen for retarding recombination of electron–hole pairs. The degradation rate in the H2O2-UV/TiO2 system was about 2.8 times faster than that in the UV/TiO2 system for solution pH below 5, and the rate increased 30% for solution pH above 6. In addition, it is observed that the reaction rate of MTBE increased quickly with H2O2 concentration at low H2O2 dosages, but the rate was independent of H2O2 dosage when adding too much H2O2.

scholarly journals Global Climate Data Processing and Mapping of Degradation Mechanisms and Degradation Rates of PV Modules

Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4749 ◽  
Author(s):  
Julián Ascencio-Vásquez ◽  
Ismail Kaaya ◽  
Kristijan Brecl ◽  
Karl-Anders Weiss ◽  
Marko Topič
Keyword(s):  
Degradation Rate ◽  
Global Climate ◽  
Global Scale ◽  
Degradation Mechanisms ◽  
Climate Data ◽  
Pv Systems ◽  
Degradation Rates ◽  
Pv Modules ◽  
Long Term Performance ◽  
Term Performance

Photovoltaic (PV) systems are the cheapest source of electricity in sunny locations and nearly all European countries. However, the fast deployment of PV systems around the world is bringing uncertainty to the PV community in terms of the reliability and long-term performance of PV modules under different climatic stresses, such as irradiation, temperature changes, and humidity. Methodologies and models to estimate the annual degradation rates of PV modules have been studied in the past, yet, an evaluation of the issue at global scale has not been addressed so far. Hereby, we process the ERA5 climate re-analysis dataset to extract and model the climatic stresses necessary for the calculation of degradation rates. These stresses are then applied to evaluate three degradation mechanisms (hydrolysis-degradation, thermomechanical-degradation, and photo- degradation) and the total degradation rate of PV modules due to the combination of temperature, humidity, and ultraviolet irradiation. Further on, spatial distribution of the degradation rates worldwide is computed and discussed proving direct correlation with the Köppen-Geiger-Photovoltaic climate zones, showing that the typical value considered for the degradation rate on PV design and manufacturer warranties (i.e., 0.5%/a) can vary ± 0.3%/a in the temperate zones of Europe and rise up to 1.5%/a globally. The mapping of degradation mechanisms and total degradation rates is provided for a monocrystalline silicon PV module. Additionally, we analyze the temporal evolution of degradation rates, where a global degradation rate is introduced and its dependence on global ambient temperature demonstrated. Finally, the categorization of degradation rates is made for Europe and worldwide to facilitate the understanding of the climatic stresses.

Compared to Two Kinds of Methods for the Degradation of an Anthraquinone Dye Reactive Brilliant Blue KN-R

2014 ◽  
Vol 955-959 ◽  
pp. 2254-2260
Author(s):  
Hui Yu ◽  
Chun Ji Jin ◽  
Ruo Chen Sun ◽  
Ming Liu ◽  
Yuan Le Yang
Keyword(s):  
Microbial Fuel Cells ◽  
Degradation Rate ◽  
Brilliant Blue ◽  
Order Kinetic ◽  
Anthraquinone Dye ◽  
Degradation Rates ◽  
Two Systems ◽  
Degradation Reaction ◽  
Electric Generation ◽  
Two Stages

Taking anthraquinone dye reactive brilliant blue KN-R as a target pollutant, this paper studied KN-R degradation rates and electric generation performances in the system of Fe2+/PDS and Fe2+/PDS-MFC. The Fe2+/PDS system is that persulfate (PDS) is activated by ferrous iron (Fe2+) ,while Fe2+/PDS-MFC system is using Fe2+/PDS system as the cathode of microbial fuel cells (MFC) .The results showed that in the two systems, the KN-R degradation rate was increased and then decreased with the increase of initial Fe2+dosage. With the increase of pH, the KN-R degradation rapid declines. In the two systems, both of the KN-R degradation reaction was divided into two stages. In addition, the process of reaction conforms to the first-order kinetic equation. Compared with Fe2+/PDS system, the Fe2+/PDS-MFC system’s ability to degrade pollutants have little change, the main advantage of Fe2+/PDS-MFC system is able to obtain higher and more stable power. Under an optimal condition, the maximum power density achieved 294.07 mW/m2, the KN-R degradation rate was 96.90%.

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