Search results for " nitrogen"
showing 10 items of 319 documents
An advanced control strategy for biological nutrient removal in continuous systems based on pH and ORP sensors
2012
[EN] A fuzzy logic-based control system that uses low-cost sensors for controlling and optimizing the biological nitrogen removal in continuous systems has been developed. The novelty of this control system is the use of several pH, ORP, and dissolved oxygen (DO) sensors instead of on-line nitrogen sensors/analyzers. The nitrogen control system was developed and implemented in a UCT pilot plant fed with wastewater from a full-scale plant. The developed nitrification controller allows the effluent ammonium concentration to be maintained below the effluent criteria discharge with the minimum energy consumption. The denitrification process controller allows the energy consumption derived from …
Ecology of Denitrifying Prokaryotes in Agricultural Soil
2007
Denitrification is a microbial respiratory process during which soluble nitrogen oxides are used as an alternative electron acceptor when oxygen is limiting. It results in considerable loss of nitrogen, which is the most limiting nutrient for crop production in agriculture. Denitrification is also of environmental concern, since it is the main biological process responsible for emissions of nitrous oxide, one of the six greenhouse gases considered by the Kyoto protocol. In addition to natural variations, agroecosystems are characterized by the use of numerous practices, such as fertilization and pesticide application, which can influence denitrification rates. This has been widely documente…
Synthetic, structural and biochemical studies of polynuclear platinum(II) complexes with heterocyclic ligands.
2008
"Non-classical" di- and trinuclear Pt(II) complexes with polydentate nitrogen ligands; ionic [(PtCl(2))(2)(tptz)(2)(mu-PtClNCPh)]Cl (1) [tptz =2,4,6-tris(2-pyridyl)-1,3,5-triazine], [(PtCl(2))(2)(bptz)(2)(mu-Pt)]Cl(2) (2) [bptz = 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine] and neutral [(PtCl(2))(2)(tptz)(2)(mu-PtCl(2))](H(2)O)(4) (3), [(PtCl(2))(2)(mu-tppz)](CHCl(3)) (4) [tppz = 2,3,5,6-tetra(2-pyridyl)pyrazine] complexes, have been prepared and structurally characterized. The neutral tptz and tppz complexes present three and two separate PtCl(2) moieties, respectively, in a cis position, presumably acting in a bifunctional mode towards DNA; the cationic tptz and bptz complexes contain monofuncti…
In vitro and in vivo characterization of a new organic nitrate hybrid drug covalently bound to pioglitazone.
2014
<b><i>Background/Aims:</i></b> Organic nitrates represent a group of nitrovasodilators that are clinically used for the treatment of ischemic heart disease. The new compound CLC-3000 is an aminoethyl nitrate (AEN) derivative of pioglitazone, a thiazolidinedione antidiabetic agent combining the peroxisome proliferator-activated receptor &#947; agonist activity of pioglitazone with the NO-donating activity of the nitrate moiety. <b><i>Methods:</i></b> In vitro and in vivo characterization was performed by isometric tension recording, platelet function, bleeding time and detection of oxidative stress. <b><i>Results:</i></…
Fresh Pod Yield, Physical and Nutritional Quality Attributes of Common Bean as Influenced by Conventional or Organic Farming Practices
2022
The aim of the current study wat to comparatively assess the impact of different nitrogen (N) fertilization schemes on fresh pod yield and yield quality in either organically or conventionally grown common beans (Phaseolus vulgaris L.). Prior to common bean crop establishment, the experimental field site was cultivated following either organic (a) or conventional (b) farming practices with a winter non-legume crop (Brassica oleracea var. italica) (BR), or (c) with field bean (Vicia faba sp.) destined to serve as a green manure (GM) crop. At the end of the winter cultivation period the broccoli crop residues (BR) and green manure biomass (GM) were incorporated into the soil and the plots tha…
Non-Saccharomyces Yeasts nitrogen source preferences: Impact on sequential fermentation and wine volatile compounds profile
2017
International audience; Nitrogen sources in the must are important for yeast metabolism, growth, and performance, and wine volatile compounds profile. Yeast assimilable nitrogen (YAN) deficiencies in grape must are one of the main causes of stuck and sluggish fermentation. The nitrogen requirement of Saccharomyces cerevisiae metabolism has been described in detail. However, the YAN preferences of non-Saccharomyces yeasts remain unknown despite their increasingly widespread use in winemaking. Furthermore, the impact of nitrogen consumption by non-Saccharomyces yeasts on YAN availability, alcoholic performance and volatile compounds production by S. cerevisiae in sequential fermentation has b…
High-Dose Torasemide is Equivalent to High-Dose Furosemide with Hypertonic Saline in the Treatment of Refractory Congestive Heart Failure.
2007
Objective: A randomised, double-blind study was performed to evaluate the effects of the combination of high-dose torasemide and hypertonic saline solution (HSS) infusion versus high-dose furosemide (frusemide) and HSS in the treatment of refractory New York Heart Association class IV congestive heart failure (CHF). Materials and methods: Eighty-four patients (55 males, 29 females) with refractory CHF, aged 55–84 years, with an ejection fraction <35%, serum creatinine <2 mg/dL, blood urea nitrogen ≤60 mg/dL, a reduced urinary volume and a low natriuresis, were randomised to two groups. Group 1 (27 males, 15 females) received an intravenous infusion of furosemide 500mg plus HSS (150mL of 1.4…
Photocatalytic ozonation under visible light for the remediation of water effluents and its integration with an electro-membrane bioreactor
2018
Abstract Photocatalysis and photocatalytic ozonation under visible light have been applied for the purification of a complex aqueous matrix such as the grey water of Masdar City (UAE), by using N-doped brookite-rutile catalysts. Preliminary runs on 4-nitrophenol (4-NP) solutions allowed to test the reaction system in the presence of a model pollutant and to afford the relevant kinetic parameters of the process. Subsequently, the remediation of grey water effluent has been evaluated in terms of the reduction of total organic carbon (TOC) and bacterial counts. The concentration of the most abundant inorganic ionic species in the effluent has been also monitored during reaction. Photocatalytic…
Transport properties of nitrogen doped p‐gallium selenide single crystals
1996
Nitrogen doped gallium selenide single crystals are studied through Hall effect and photoluminescence measurements in the temperature ranges from 150 to 700 K and from 30 to 45 K, respectively. The doping effect of nitrogen is established and room temperature resistivities as low as 20 Ω cm are measured. The temperature dependence of the hole concentration can be explained through a single acceptor‐single donor model, the acceptor ionization energy being 210 meV, with a very low compensation rate. The high quality of nitrogen doped GaSe single crystals is confirmed by photoluminescence spectra exhibiting only exciton related peaks. Two phonon scattering mechanisms must be considered in orde…
Application of the Morris method for screening the influential parameters of fuzzy controllers applied to wastewater treatment plants
2011
In this paper,we evaluate the application of a sensitivity analysis to help fine-tuning a fuzzy controller for a biological nitrogen and phosphorus removal (BNPR) plant. TheMorris Screeningmethod is proposed and evaluated as a prior step to obtain the parameter significance ranking. First, an iterative procedure has been performed in order to find out the proper repetition number of the elementary effects (r) of the method. The optimal repetition number found in this study (r = 60) is in direct contrast to previous applications of the Morris method, which usually use low repetition number, e.g. r = 10 ~ 20. Working with a non-proper repetition number (r) could lead to Type I error (identify…