scholarly journals Influence of rumen ammonia concentration on the rumen degradation rates of barley and maize

1987 ◽  
Vol 57 (1) ◽  
pp. 127-138 ◽  
Author(s):  
J. Odle ◽  
D.M. Schaefer
Keyword(s):  
Degradation Rate ◽  
Structural Characteristics ◽  
Nitrogen Concentration ◽  
Ammonia Concentration ◽  
Ammonia Nitrogen ◽  
Acetate Solution ◽  
Feed Processing ◽  
Rumen Degradation ◽  
Degradation Rates ◽  
Exponential Decay Model

1. Four rumen-cannulated steers were given barley and maize diets supplemented with graded levels of an ammonium acetate solution.2. Animals were fed hourly from automatic feeders and water consumption was controlled to achieve steady-state conditions in the rumen.3. Dacron bags containing rolled barley or ground barley were incubated in the rumen of barley-fed steers, while ground maize and autoclaved maize were incubated in the rumen of maize-fed steers.4. Fractional degradation rates of dry matter were estimated for each cereal substrate incubated using a single-pool exponential decay model.5. No differences in degradation rate due to the method of feed processing were detected; however, barley was degraded at a faster rate than maize. Furthermore, the minimum rumen ammonia-nitrogen concentration required to maximize the degradation rate of barley (125 mg/l) was greater than that required to maximize the degradation rate of maize (61 mg/l).6. These results indicate that the optimal NH3-N concentration required to maximize the rate of grain digestion in the rumen is influenced by the chemical or structural characteristics of the grain.

scholarly journals Effect of the ammonia concentration on the performance of wetland microbial fuel cells

2021 ◽  
Vol 269 ◽  
pp. 01002
Author(s):  
Li Wang ◽  
Jiafeng Fu ◽  
Wenlei Wang ◽  
Yutong Song ◽  
Yan Li
Keyword(s):  
Fuel Cell ◽  
Microbial Fuel Cell ◽  
Microbial Fuel Cells ◽  
Nitrogen Concentration ◽  
Oxygen Demand ◽  
Ammonia Concentration ◽  
Ammonia Nitrogen ◽  
Internal Resistance ◽  
Removal Rates ◽  
Fixed Condition

This work explores the effect of the ammonia concentration on the wetland synthesis of microbial fuel cell (MFC) and on the production and the efficiency of sewage purification. Four ammonia concentrations from 1 to 30 mg/L have been selected. Under the fixed condition of a chemical oxygen demand (COD) concentration of 200 mg/L, a constructed wetland microbial fuel cell (CW-MFC) could be built. The results show that by selecting the optimum ammonia concentration the production of the CW-MFC could be promoted; a higher ammonia concentration (>20 mg/L) is found to inhibit the production activity of CW-MFC. In the optimum conditions, Cathode and anode thickness is 10 cm, the ammonia concentration is 10 mg/L, the COD concentration of 200 mg/L, the maximum power density of the battery is 13.6 W/m3, the corresponding current density is 148.6 A/m3 and the battery internal resistance is 270 Ω. At the ammonia nitrogen concentration of 10 mg/L, the removal rates of ammonia nitrogen and COD were up to 89.7% and 98.47% respectively. As the ammonia nitrogen concentration increased to 30 mg/L, the ammonia nitrogen and COD removal rates decreased to 74.6% and 90.69% respectively. That is, when the ammonia nitrogen concentration is 10 mg/L, CW-MFC can exhibit the best performance.

scholarly journals Efficiency of the Integrated Nitrogen Removal Device to Remove Ammonia in a Hog House

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Chen Lyu ◽  
Na Li ◽  
Ming Li ◽  
Yiyan Lyu ◽  
Zhaoying Liu ◽  
...  
Keyword(s):  
Nitrogen Concentration ◽  
Environmental Parameters ◽  
Ammonia Concentration ◽  
Ammonia Nitrogen ◽  
Ion Concentration ◽  
Ammonia Oxidizing Bacteria ◽  
Ammonia Gas ◽  
Average Temperature ◽  
New Methods ◽  
Functional Strain

It is crucial to explore new methods to deal with ammonia pollution in hog barns. In this experiment, ammonia gas generated from the decomposition of nitrogenous organic matter, such as feed and manure in hog barns, was studied. Growing environmental parameters monitored included temperature, humidity, and ammonia nitrogen concentration. For 92 days between March and May, ammonia emissions were characterized by monitoring and collecting the ammonia concentration during the selected time. The results showed that the average temperature in the hog house was 18.2 ± 2.7°C, the humidity was 62.7 ± 0.3%, and the average ammonia concentration range was 17.7∼23.1 mg m−3. The collected ammonia-nitrogen-containing wastewater that entered the denitrification device showed 173, 232, 201, and 280 mgNH4-N/L, respectively. An integrated denitrification device with anaerobic ammonia-oxidizing bacteria as a functional strain was used for denitrification treatment. Through the change of ion concentration in the incoming and outgoing water, an 85.5% average denitrification efficiency was calculated according to the denitrification reaction chemical formula. Thus, the results presented here provide data support for the future use of microbial denitrification equipment to treat ammonia in hog houses.

Influence of the Initial Nitrogen Concentration on Eliminating Nitrogen Load of Europhia Sediment Capping with Active Barrier System (ABS)

2011 ◽  
Vol 374-377 ◽  
pp. 498-503
Author(s):  
Jin Lan Xu ◽  
Lei Wang ◽  
Jun Chen Kang ◽  
Ting Lin Huang ◽  
Yu Hua Dong
Keyword(s):  
Total Nitrogen ◽  
Nitrate Nitrogen ◽  
Nitrogen Concentration ◽  
Ammonia Nitrogen ◽  
Overlying Water ◽  
Sediment Capping ◽  
Time Treatment ◽  
Total Nitrogen Concentration ◽  
Long Time ◽  
Active Barrier

Abstract: Active barrier system (ABS) capping zeolite with large surface area and strong adsorption ability is an effective way to control eutrophication of lake since it can remove ammonia in the lake released by sediment. Influence of the initial nitrogen concentration on eliminating nitrogen load of europhia sediment capping with active barrier system (ABS) were studied through an investigation of the repairment results of serious pollution period (total nitrogen concentration up to 25.33 mg/L), moderate pollution period (14.39 mg/L) and the slight pollution period (3.47 mg/L) of the ancient Canal of Yangzhou. The results showed that: (1) zeolite F1 inhibition effect is stronger than zeolite F2. More TN were removed as the initial TN concentration increased and longer rapid inhibit period were presented with the increased initial TN concentration. (2) The ammonia nitrogen in sediment could be rapidly released into the overlying water, and with lower initial TN concentration in source water, more ammonia would be released from the sediment. Long time treatment was necessary to inhibit the release of ammonia completely if the water showed a high initial TN concentration. (3) After covering zeolite, the total nitrogen in the overlying water were removed mainly through nitrification and denitrification. At the initial TN concentration of 3.47 mg/L, 14.39 mg/L, 25.88 mg/L, 61%, 45% and 52% of TN were removed by the conversion of ammonia to nitrogen gas, however, others left in water as nitrate nitrogen and nitrite residues, and 90% was nitrate nitrogen.

scholarly journals Kinetics, Mechanism, and Toxicity of Amlodipine Degradation by the UV/Chlorine Process

Water ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3150
Author(s):  
Jianye Xu ◽  
Siqi Zhou ◽  
Erdeng Du ◽  
Yongjun Sha ◽  
Lu Zheng ◽  
...  
Keyword(s):  
Acute Toxicity ◽  
Advanced Oxidation Process ◽  
High Resolution Mass Spectrometry ◽  
Ph Value ◽  
Degradation Products ◽  
Degradation Mechanism ◽  
Complete Removal ◽  
Ammonia Concentration ◽  
Ammonia Nitrogen ◽  
Toxicity Tests

The UV/chlorine process, as a new type of AOP (Advanced Oxidation Process), was utilized to treat amlodipine (AML)-containing water. The influencing factors, including chlorine dose, UV intensity, solution initial pH value, and ammonia concentration, were investigated. The degradation of AML in real water and the relative contributions of OH• and Cl• were also studied. Finally, high-resolution mass spectrometry (HRMS) and GC-MS were used to identify the possible degradation products. The results demonstrated that the AML degradation process was fitted with apparent first-order kinetics. AML degradation had a positive correlation with UV intensity and chlorine dose, and a negative correlation with ammonia concentration. In the presence of ammonia nitrogen and DOM, the removal of AML from real water was reduced. OH• made a dominant percentage contribution of 55.7% to the degradation of AML. Sixteen intermediates were detected and identified. A possible degradation mechanism was also proposed. Acute toxicity tests and risk prediction both illustrated that the complete removal of AML does not guarantee the reduction of acute toxicity, but a prolonged degradation promoted the detoxification of toxic intermediates. The UV/chlorine process can be regarded to be an effective method to remove AML and reduce ecological risk.

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.

scholarly journals Cometabolism of Trihalomethanes by Nitrosomonas europaea

2005 ◽  
Vol 71 (12) ◽  
pp. 7980-7986 ◽  
Author(s):  
David G. Wahman ◽  
Lynn E. Katz ◽  
Gerald E. Speitel
Keyword(s):  
Drinking Water ◽  
Rate Constants ◽  
Degradation Kinetics ◽  
Drinking Water Treatment ◽  
Nitrosomonas Europaea ◽  
Ammonia Nitrogen ◽  
Degradation Rates ◽  
Ammonia Oxidizing Bacterium ◽  
Treated Drinking Water ◽  
Bromine Substitution

ABSTRACT The ammonia-oxidizing bacterium Nitrosomonas europaea (ATCC 19718) was shown to degrade low concentrations (50 to 800 μg/liter) of the four trihalomethanes (trichloromethane [TCM], or chloroform; bromodichloromethane [BDCM]; dibromochloromethane [DBCM]; and tribromomethane [TBM], or bromoform) commonly found in treated drinking water. Individual trihalomethane (THM) rate constants ( \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(k_{1_{THM}}\) \end{document} ) increased with increasing THM bromine substitution, with TBM > DBCM > BDCM > TCM (0.23, 0.20, 0.15, and 0.10 liters/mg/day, respectively). Degradation kinetics were best described by a reductant model that accounted for two limiting reactants, THMs and ammonia-nitrogen (NH3-N). A decrease in the temperature resulted in a decrease in both ammonia and THM degradation rates with ammonia rates affected to a greater extent than THM degradation rates. Similarly to the THM degradation rates, product toxicity, measured by transformation capacity (Tc ), increased with increasing THM bromine substitution. Because both the rate constants and product toxicities increase with increasing THM bromine substitution, a water's THM speciation will be an important consideration for process implementation during drinking water treatment. Even though a given water sample may be kinetically favored based on THM speciation, the resulting THM product toxicity may not allow stable treatment process performance.

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).

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