Science topic
Denitrification - Science topic
Nitrate reduction process generally mediated by anaerobic bacteria by which nitrogen available to plants is converted to a gaseous form and lost from the soil or water column. It is a part of the nitrogen cycle.
Questions related to Denitrification
What is the behavior of anaerobic bacteria in deep salty groundwater with high level of chlorine? Is the nitrate level deceasing and is denitrification controlled by excess chlorine? Thanks
Lab scaled biofilm reactor are operated for treatment of wastewater with initial pH = 7.44, the pH of effluent after treatment from reactor increased to 8.15. The percentage removal of COD is greater than 70% with nitrification rate being higher than denitrification rate. What might be the possible reasons for rise in pH contradictory to the decrease in pH that must be observed during reduction of COD and nitrification occurring in the system?
At what cathodic potential (range) we can perform the electrocatalytic denitrification ?
Hi All,
I wondered if anyone knows of published examples of the denitrification capacity (e.g., weakly reducing aquifers) of an aquifer being overwhelmed? I thought that weakly buffered (e.g., NO3-or MnIV-reducing) aquifers might be more easily overwhelmed by high nitrate loading rates.
Many thanks for considering my question.
Biodenitrification was performed using Thiobacillus denitrificans in the presence of nanostructures.
Basal Salt Medium culture medium was used to study the denitrification process of Thiobacillus denitrificans ATCC 23644. In this medium, potassium nitrate was added to the medium as the only source of nitrate. To create anaerobic conditions, 4 ml of bacterial suspension was added to 40 ml vials containing 36 ml of BSM medium. The flasks were heated in an incubator (30 ° C) for 24-48 hours. To investigate the nitrification process, microorganisms were inoculated in BSM medium with a concentration of 300 mg / L nitrate. Sampling was performed with an interval of 6 hours and the vials containing microorganisms were centrifuged for 20 minutes at 5000 rpm. After centrifuge, the samples were passed through filter paper and the optical absorption of soluble nitrate at 410 nm was read using a spectrophotometer and the concentration of soluble nitrate would be obtained.
Now I want to measure the growth of microorganisms by spectrophotometer at the same time as measuring nitrate, in other words, I want to conclude that as the growth of microorganisms increases, nitrate in the culture medium decreases. How should I measure the growth of a microorganism? What wavelength should I use? Is a half McFarland concentration of microorganisms necessary?
If you can help me to complete this method, I am very grateful.
Metal nanoparticles St-Fe0 and CQD-Fe0 were incubated in BSM medium with nitrate concentration of 300 mg / L, in three concentrations of nanoparticles equal to 0.05, 0.5, 1 g at 25, 30 and 35 ° C for 48 hours.
In order to investigate the effect of nanoparticle concentration and temperature on the denitrification rate of metal nanoparticles, sampling was performed after 48 hours and the results were evaluated through nitrate kit.
Dear all,
Here is a question about the C/N ratio:
We evaluated a novel heterotrophic nitrification-anaerobic denitrification bacteria for nitrogen removal using formic acid as the sole carbon source. The treated wastewater is a biogas slurry that was generated from pig manure digestion, and it has a pH of 9.55 and NH4+-N concentration of 683±8.49 mg/L. The C/N ratios used were 10, 20, 30, 40, and 50. But the optimum one was 40 in the flask trial, which is high. So, with such a high C/N ratio, is there any justification for the economic aspect of the approach in the large-scale application?
Thanks in advance!
the soils I am experimenting with is highly sodic (high Na) with a pH of 8.3 to 8.6. When I checked the NH4+ and NO3- concentrations in the soil compared to a reference soil from an unaffected area, NH4+ of the test soil was similar to reference soils at all times; however, NO3- is gradually decreasing. I have two assumptions,
1) Sodicity/alkalinity induce denitrification
2) Sodicity/Alkalinity inhibit nitrification
pulsator technology is used widely in water treatment, but it is an innovation to use it in a SBR process , whili it can enhance the handelling of sludge in settling and draw phase and finally an efficient denitrification.
i wanna know about the primary considerations or impediments in using this technology, of course if there is any !
I am about to start experiments on nitrogen removal by MBBR. I started some trial tests in batch mode to see if biofilms form before the main ones, and I have some questions regarding the operation.
1) First and foremost, water keeps evaporating from the reactor, and I do not know how to prevent this.
2) What is the best inoculum (seed sludge) to substrate ratio to start the experiments?
3) What is the best way to measure the filling ratio?
4) What is the optimum range for DO? I have seen several ranges, and I do not know which is the best.
Any other suggestions and references are welcomed.
Dear community,
I have bacteria that perform the first step of denitrification, so they reduce nitrate to nitrite.
Nitrite accumulates to 1.5 mM in my culture. Then the bacteria stop being active. I assume that there is some kind of feedback inhibition. I would like to remove nitrite from the system so that the bacteria can completely consume all the nitrate. Is there a chemical doing this, which I could use as supplement for my media?
Thanks a lot!
Can somebody advise of a publication that determines the nitrification and denitrification rates of mixed toilet waste (aka feces and urine only) or at least of pure urine in an MBR or CAS?
I am interested in knowing how much ammonium (nitrification) and nitrate (denitrification) nitrogen is removed per unit of time and unit mass of VSS.
Thank you!
Hello colleagues,
We are trying to induce a liner consequences reaction of nitrification follows de nitrification processes. The main challenge is the redox potential. we need to reduce it from 250 mv by the nitrification chamber into -50 mv by the anoxic denitrification chamber. We are using a potassium carbonate to reduce the redox potential. Any new ideas how to reduce the redox potential?
I conducted potential nitrous oxide emission assessment from soil samples following the method previously used by Zhong et al 2018. The samples were incubated for 48 hours, taking gas samples at 0, 24 and 48 hours respectively.
I have read the N2O concentrations from the gas samples collected using GC, and this data is available. Also, available is the soil-dry weight of the soil samples used in the assessment.
I feel somehow stuck at the procedure for final calculation of the potential N2O production using the available concentration readings from the GC.
Has anyone previously undertaken such, or a similar study, and can quickly unstuck me?
How do i proceed to determine the final N2O emitted from the soil samples ?
Thanks in advance
I was reading about hydraulic performances and Nitrogen removal processes in bioretention cells as LID, or BMP practices, and just wondered if there would be advantages (or significant negative impacts) if a gravel layer is put on top of the media layer.
There are some aspects that I think of. Any discussions are welcome.
When putting gravel storage layer on top:
(a) we have similar water storage capacity. If we install drainage pipes or orifices in storage layers, we can better prevent overflow (runoff peak goes: gravel layer--discharge vs media layer--gravel layer--discharge)
(b) worry less about groundwater mounds, groundwater intrusion or draining too much groundwater, because the media layers have wetting-drying curves more similar to the original soil
(c) probably can be easier maintained. Consider: sedimentation happen primarily in gravel layer, and the next rain event can flush the large pores
(d) DO drops before water enters soil layer, thus soil media can be more efficient for denitrification per depth
(e) In addition, do denitrification bacteria has higher activity, because the soil layer is adjacent to original soil? Can ammonification and nitrification happen in gravel layer or the interface, and provide higher nitrate concentration to enhance denitrification?
Expecting analytical approach..
I am performing a denitrification reaction using potassium nitrate. But before performing the experiment I want to know the approximate amount (theoretical) of intermediates formed in the reaction which will help me to compare between the theoretical and experimental amounts of intermediates formed in the denitrification reaction. So can stoichiometry be used for measuring the intermediates formed in denitrification or are there any other methods by which I can calculate the theoretical amount of intermediates formed in denitrification?
Hello,
do You know any methods of measurement how many (in cm3 or other units) of undissolved gas (mainly nitrogen) is in activated sludge sample. For example im interested in measurement of how nitrogen bubbles behave after denitrification reactor. How many of them remains trapped in sludge.
Hi everyone,
I am designing a wastewater treatment plant for a company which Our company only uses Category III raw materials from healthy slaughtered animals and is approved and certified accordingly in accordance with the applicable regulations.
Our company only uses Category III raw materials from healthy slaughtered animals and is approved and certified accordingly in accordance with the applicable regulations.
Our company only uses Category III raw materials from healthy slaughtered animals and is approved and certified accordingly in accordance with the applicable regulations.
Our company utilized exclusively raw materials of Category III of healthy slaughtered animals and is also approved and according to current regulations for certified accordingly.
Our company utilizes exclusively raw materials of healthy slaughtered animals and produces bone fat and animal protein from it. I would like to have two activated sludge basins, first aerobic for denitrification and then aerobic for nitrification. The cod content of waste water is 3600 mg/l. How can I find out the easily degradable content of COD which can be used as carbon content for denitrification?
How can I calculate the amount of required COD for denitrification?
I would appreciate it, if someone could help me.
Zahra Alipour
Why does COD increase over time when external carbon sources are added in the denitrification process in waste water?
After 1 hour, the concentration increased from 30mg/l to 40mg/l after 20 hours.
carbon source : ethanol
Hello everyone,
In my experiment, I find that N2O emission rates from long-term warmed soils (+2.5 °C; 10 years) do not change during a four-week drought compared to pre-drought level. In control soils (no warming) emission rates decline almost 100%. I am thinking that the long-term warmed soils are better aerated due to intesified dryout dynamics after each wetting and thus soil disaggregation. I get that this may pronounce waterlogging in rewetted soils after drought and influence denitrification. But how does this look like at drought conditions? Which shift on organismal or functional level (within nitrification?) can serve as an explanation for mny observations?
I appreciate any suggestions,
best regards!
My lab designed a qPCR assay for amplifying the denitrification gene nirS from DNA extracted from soil. The assay has worked perfectly in the past with almost perfect efficiency and gene copy number results. However, recently we noticed that the assay was underestimating by 2 log (Should be at least 10^5, but coming out as 10^3). This was noticed as the gene copy numbers of the external positive control, Pseudomonas aeruginosa, were 2 logs lower than they should be. We tested a number of things to explain this. We regrew and extracted fresh DNA from a new strain of P. aeruginosa, yet the results were the same. BSA was used in this assay, but was also found to not affect gene copy numbers to this extent. Standards and stocks were all re-quantified using Qubit. We are still unsure what is causing the underestimation and how we should to proceed. Does anyone have any suggestions for troubleshooting this issue? Or know of any published research that ran into similar issues? All suggestions are welcome, thank you.
what will happen if we combined process of washing hydrogen sulfide from biogas and
denitrification on the WWTP line
I collected effluent samples from a biorention column with the hopes of collecting denitrifying bacteria, following the procedure described in “Inhibition of assimilatory nitrate reductase activity in soil by glutamine and ammonium analogs” by Gregory W. McCarty and John M. Bremner.
To my knowledge, there are at least 3 microbial processes in soils which use NO3- as a substrate:
- The assimilatory reduction of NO3- to ammonium (NH4+)
- The dissimilatory reduction of NO3- to NH4+
- and denitrification, the dissimilatory reaction of NO3- to dinitrogen (N2) and nitrous oxide (N2O)
In the article, L-Glutamine is used to inhibit the activity of assimilatory NO3- reductase (ANR). Might L-Glutamine affect other microbial processes related to denitrification?
I find opposite and contradictory range for ORP which reported by various researchers who worked on denitrification. I need to reliable reference for ORP range in aerobic, anoxic and anaerobic metabolic conditions. thanks for your contribution
1 mole of lactate denitrifies 2.2 moles of nitrate (bacterial denitrification).
I need to denitrify 1L of 6000 ppm nitrate and I have 60% Sodium lactate solution. how do I proceed with the calculation?
Hello every one,
My master's thesis focuses on the development of a decentralized wastewater treatment method with the purpose of irrigation reuse in a town in India. Based on my research, there is no guideline for irrigation reuse in India. I tried to use international guidelines like USEPA, WHO or EU. All of these guidelines have a focus on human leath risk and the requirments for pathogen removal and BOD are mentioned in them. But they did not mention the required amount of nitrification and denitrification in treatment process. O could not find any limitation for nitrate and ammonia or TN concentration in final effluent. However, I think becuse of ground water pollution risk, there should be a limitation. Otherwise, the nitrate can infiltrate into groundwater. Is there any one who could help me. I really appreciate it.
- I have discovered a novel species of bacteria that belongs to Pseudomonas genus. On the basis of rpoD gene (individually) and 16sRNA+rpoD genes based (concatenated) trees,it shows close similarity to P.alcaligenes (P.aeruginosa lineage).
- Genome blast distance phylogeny (GBDP) tree created using Type strain genome server (TYGS), mirrors the similar results with 100 % bootstrap value. Moreover, the "type species" suggested by the TYGS platform on the bases of genome sequences are P.aeruginosa and Azomonas agilis.
My Question: Can I directly say that this soil bacterium is human pathogen? OR This bacterium holds potential for being human pathogen?
P.S: The bacterium was isolated from grassland soil to study their role in nitrogen cycle , more specifically, respiratory ammonifcation /Dissimilatory nitrate reduction/ denitrification.
Regards,
Timsy
Rhizosphere microorganisms are the main drivers of turnover of organic C, N, and P and thus recycling of organically bound nutrients, for example by ammonification and nitrification, but may also increase N loss via denitrification.
I have conducted several lab-based incubation experiments to test how estuarine sediment reacts to different nitrate loading. I have a large data set of nutrient and carbon data, as well as data such as pH, ORP, and Conductivity. I havent been able to find a way through literature review, but thought maybe someone might have some advice.
Kindly provide detailed reactions involved in heterotrophic nitrification and aerobic denitrification and how to calculate the gibbs energy of these process
Dear all,
I was wondering how to determine the denitrification potential of water. Most references are focused on sediment or soil. Can these methods also be used in determination denitrifation of water , epiphyton or biofilm?
Really appreciate your feasible suggestions and references.
Thanks.
Hi, everyone, anybody know the N2O production rate of nitrifiers and denitrifiers on a single cell level, or have related work recommended? especially denitrification.
i m working on Sulfur and nitrate removal from wastewater treatment. during reviewing papers i observe that the researchers claim that during the autotrophic denitrification of Sulfur and nitrate in the reactor, ammonium (NH4) accumulated in the reactor. but the problem is that why it is accumulated, no one explain the reason. so i want to know why it is accumulated in the reactor. For example i will give one paper as a reference i.e. " Effect of S/N ratio on sulfide removal by autotrophic denitrification". if any one want to see the paragraph, i have highlight it in the paper and have added the paper here..
Need reasonable answers...
Current, I am simulating the OPR for irreversible biochemical reactions. The reactions mainly include the processes of nitrification, denitrification, carbon oxidized by oxygen and so on. I noticed that lots of reference use Nernst Equation to solve the ORP, but I tired this method for about half a month and still do not get the results that are well matched with the experimental data.
It is also said that Nernst Equation is only suitable for equilibrium reactions. Does someone who familiar with the ORP calculation can provide some advices and recommend a method for irreversible kinetic reactions. If Butler-Volmer equation is suitable for my situation?
Hi, everyone, now I have a question about the efficiency of denitrification and nitrification in N2O production. do you know is there paper or data that talk about this question?
Is the denitrification process and Electric Conductivity related?
can you suggest me some paper or other documents to understand the relations.
Thank you
Hi, everyone, here I have some question for you, in order to clarify the N2O production problem, I have done some work in four estuaries of China, focused on the abundance (DNA),activity (cDNA) and divesity of N2O releated groups using quantitive PCR and sequencing method, combined with biomarkers such as amoA(AOA/AOB),nirS/K and nosZ(I/II).
however, when it comes to the explaination of the result , I found that biochemical physiology knowlege is important for understanding the reault and drawing a seasonable conclusion. so now I want to seek advice about how do you think about the relationship between oxygen and denitrification? how dose oxygen influence denitrification? on the distribution of gene or through transcriptional and metabolic regulation?
I have to perform a potential denitrification assay on soil samples to measure the capacity of the soil to carry out denitrification under optimal conditions. To perform this assay, the soils need to be made up to 70% water holding capacity, while also having 2ml of nutrient solution added to them. To do this, I calculate the target water volume I need to add to each soil, using gravimetric water content and WHC. I then subtract the 2ml nutrient solution and I am usually left with a small volume of water I need to add to make the soils up to 70% WHC.
However, this time my soils are too damp and the calculated target water volume for each soil is just under 2ml. I do not have the option of sampling again, so I was wondering is there any way of reducing the volume of nutrient solution I add (usually 2ml) to 1ml, while keeping the concentration of the solution the same?
To make the nutrient solution:
i. 75 mM KNO3 (0.758274 g / 100 mL)
ii. 37.5 mM Na-succinate (0.45039 g / 100 mL)
iii. 25 mM glucose (0.6076875 g / 100 mL)
iv. 75 mM Na-acetate (0.61525725 g / 100 mL)
v. Sterile H2O (100 mL)
Then 2ml is added to each sample. Would I simply dissolve the reagents in 50ml water, then add 1ml to each sample? Sorry if this is a basic question, but I just can't seem to wrap my head around it...
We have conducted a field experiment to evaluate the effects of infiltration trenches and improved grass species on biomass productivity and soil quality. The result indicates that water conservation through infiltration increased biomass productivity while the available form of nitrogen (ammonia and nitrate) content decreased, but the total N content increased. What would be the possible explanation? The reduction in available N could be related to the increased uptake by the grass, and possible denitrification due to increased soil moisture content because of infiltration trench. The organic matter content has increased with the increased biomass- can this alone explain the increase in total N?
Hi everyone
It is well-know that most of soil N2O emissions come from N-fertilization. Leguminose perennial crops such as Medicago sativa can reduce N2O emissions, but how?
I understand that such crops do not require any N-fertilizaion (Thus, we have an indirect reduction of emission) and consuidering a life-span of 3-5 years with no soil tillage we reduce the soil areation.
Moreover leguminose are N-Fixing crops since they perfom a symbiotic fixation of atmospheric N2.
But, the things that is still not clear to are:
1) Such N2 wich is fixed by Medicago sativa is it also an intermediate of denitrifcation/nitrification and other soil process? Or is it just the one which is present in the atmosphere?
2) If the answear to the prvious one is positive, can I say that Medicago sativa reduces N2O emission by the fixation of N2 (the intermediate of denitrification/nitrification etc.)?
3) Apart from the atmospheric N2 fixed by Medicago sativa, does this plant catchs some other N from the soil via roots?
Thank you
Has anyone had any success using DAF FM diacetate, for Nitric Oxide detection, on bacterial or archaeal cells? I am seeing very little literature using this.
If so, are there any specific techniques I should know about for getting it through the cell membrane of various bacterial groups?
I wan to set up an anaerobic/oxic/anoxic (AOA) SBR for simultaneous nitrification, denitrification and phosphorus removal with aerobic granular sludge. But I'm confused how to maintain the anaerobic and anoxic phase in AOA system.
Even in nitrogen fixation, both candidates (bugs) can participate but in the case of nitrification, only bacteria? Expecting a good explanation.
Regards!
I have found published research using the the acetylene inhibition technique but what is this the best method?
Not getting 100% conversion of NO3 to N2.
feed:
CBOD5 -150mg/L
TSS -200mg/L
Ammonia N -60mg/L
TP -10mg/L
I'm PhD candidate of hydrogeology course and interested to read the report of your project( Assessments of denitrification in a karst aquifer system), if it's possible please let me know.
Best Rigards
Majid Kazemi
Culture media for denitrifying bacteria promotion and isolation.
I have used activated sludge in water denitrification and would like to do denitrifying bacteria identification to infer if they are involved in the process. I don't know which analysis should be carried out and how I can remove bacteria from granular support (the microbial cells are immobilized on graphite)
I need to analyse Monod kinetics for nitrogen removal from wastewater. Can anyone provide me with alternative biomass estimation methods( instead of VSS)?
A current modern trickling filter (TF) system with plastic filters has an input of BOD = 200 mg/L, COD = 350 mg/L and TN = 45 mg/L (effluent volume being 15,000 m3/d) has an output (in mg/L) of BOD = 50, TKN = 15, NO3-N = 3, NH4 = 10, TP = 5 and DRP = 3.
Given the high NH4-N in the TF effluent, aeration (by diffusers) appears to be the next obvious step to nitrify. Should such an aeration being performed can good nitrification be achieved without introducing RAS given there is already 50 BOD being present? Given nitrification requires CO2 as a C source, why would it need RAS (organic-C)? Please ignore the next steps involved in denitrification after full nitrification. If you could share any existing cases rather than laboratory studies that will be great.
Kind regards
Selva
I am looking for data to run Machine learning algorithms to estimate Dissolved oxygen control of the activated sludge wastewater treatment process using model predictive control.
Historical data from a SCADA system may work.
I am working on N2 production by none denitrifying bacteria. To be sure that N2 produced by these organisms actually is from the N2O route, I need to spike the culture medium with labelled N2O and trace the yield of labelled N2
Sexual inversion of fish.
Monosex production for intensive cultivation.
The hypothesis is that the protons formed during the nitrification react immediately in the denitrification reaction (in a combined system). In a separated system the protons formed during nitrification will react with bicarbonate forming CO2 + H2O leading to a higher decrease in TIC compared with the combined system.
NH4+ + 1,5 O2 -> NO2- + H2O + 2 H+ (nitrification)
NO2- + 0,5 O2 -> NO3- (nitrification)
CH2O + 0,8 NO3- + 0,8 H+ -> 0,4 N2 + 1,75 H2O +1,25 CO2 (denitrification)
I am looking for elaboration for measurement of nitrates and ammonium in soil through SKALAR METHODS, but the SKALAR instrument that we have in our Lab, there I have seen, mentioned only for nitrate+nitrite, ammonia and ortho phosphate, how I can calculate ammonium in this method? because I want to estimate the ammonium and nitrate to find out ammonification and nitrification?
why is nitrite reduction process associated with denitrification is the most sensitive step to dissolved oxygen concentration while nitrate reduction is the least sensitive step to DO?
There are some literature which states a decline in the rate of Nitrification and increased rate of Denitrification in saline soil. But I am wondering if Sodium ion interact with Nitrate in positive or negative way and its effect mechanism in Non - saline soil.
Gas chamber is required for monitoring Ammonia volatilization loss and denitrification loss from Rice fields fertilized with neem coated urea and polymer coated urea. Please provide me some mail addresses,contact numbers of authentic manufactures.
Denitrification-How is actual COD/NO3 determined for denitrification? Is it ok to take the difference of COD consumed/NO3 reduced for each day
The articles I follow as guidelines tend to have differences on to why they decided to use X amount of N-fertilizer to lead to nitrification and denitrification processes. I don't want to *poison my microbiota within the soil but I don't want to prohibit them to feed on a substrate either.
Any idea or any standard guideline I should be aware of when considering amounts of NH4Cl and/or KNO3 specifically for promoting these two processes?
Thank you!
I have read many studies which use anaerobic incubation method to determine PMN. My understanding is that when soils are flooded with water, denitrification processes are enhanced because of lack or oxygen which result in some N lost as a gas and some leached. Are results from this method of incubation in determining PMN an accurate representation of the mineralization process? Does this method then encourage waterlogging in soils?
In fact I search a method via instrument or equipment measuring quickly, but may be otherways too
I want to study treatment of NO3.NO2 by activated carbon. We prepared the following synthetics solution ;KNO3. NH4Cl. What conservation status of NO3 ions for [NO3] in t = 0 constant (stop nitrification and denitrification).
My project will focus on effects of water level on ecosystem functioning. The study area is lowland polder (clay) grassland and pasture land, so grasses will dominate the surface.
I want to measure denitrification (only N2O) from decomposing legume cover crop residues in a controlled growth chamber incubation. In some papers, authors add acetylene to the head space. I read this is to prevent N2O from being converted to N2. Is this true? Is it critical to use acetylene for these kind of studies?
If I maintain field capacity, but flush columns on sampling dates, is there a method I can use to return to field capacity quickly and avoid denitrification losses? I am not sure how vacuum suction works. I also have many several replications and don't knowif suction is feasible.
As we all know that In the environment soil, primer of nitrite reductase(nirk) has been designed ,but primer of nitric oxide reductase(P450nor) has not .So if I use the primer of nirk to amplify envrionment soil and the primer of cyp55(A1,A2,A3,A4,A5) to amplify fungal strains(isolate from the environment soil ) ,the result whether can explain the fungal denitrification in the environment soil?
Hi,eyeryone.In the process of fungal denitrification,nitrite reductase(nir) and nitric oxide reductase(P450nor) participate in it. And the nirk gene encodes the nitrite reductase,cyp55 gene encodes nitric oxide reductase.now I have find the primer of nirk for PCR of soil samples,but the question is that cyp55 is a super family,different strain has different primer of cyp55,for example, primer of Fusarium oxysporum's cyp55A1 gene has been fund,now my sample from the rice paddy soil ,so I want to find the universal primer target cyp55 gene,do you konw this primer?I hope anything you know could tell me.thanks very much.I need your help.
Recently,I search some papers about the genes in the process of fungal denritriication,and I have search some papers about nirk gene and cyp55 gene,but I can not find any papers about the genes of nitrite reductase in the fungal denritrification,such as dNar and aNar gene.If you know some papers about the genes in the function,expecially about dNar and aNar,please recommend some related papers for me.thanks very much.
Recently I read Hirofumi Shoun‘paper “denitrification by fungi ”,in this paper ,he said that some of fungus lack N2O reductase? I don not konw why ,whether because some of them lack p-450nor?or depend on species? I can not contact Hirofumi Shoun,so if you konw the reason, please tell me the reseason .or tell me some related papers.thank you very much!
if this organism could denitrify efficiently in the existence of DO, why do we need thiosulfate then ?
Table 5.1 page 110 in IWA report No 9: Activated Sludge Models ASM1, ASM2, ASM2d and ASM3: Conservatives of Nitrogen:
I would like to know how to calculate conversion factors of SNH4, SN3 and SNOx to get 1? Because I want to calculate this value of SNO2, SN2O and SNO.
Thank you