Search results for "Phosphorus"

Calibration and simulation of ASM2d at different temperatures in a phosphorous removal pilot plant

2006

In this work, an organic and nutrient removal pilot plant was used to study the temperature influence on phosphorus accumulating organisms. Three experiments were carried out at 13, 20 and 24.5 degrees C, achieving a high phosphorus removal percentage in all cases. The ASM2d model was calibrated at 13 and 20 degrees C and the Arrhenius equation constant was obtained for phosphorus removal processes showing that the temperature influences on the biological phosphorus removal subprocesses in a different degree. The 24.5 degrees C experiment was simulated using the model parameters obtained by means of the Arrhenius equation. The simulation results for the three experiments showed good corresp…

Size control of InAs∕InP(001) quantum wires by tailoring P∕As exchange

2004

The size and emission wavelength of self-assembled InAs∕InP(001) quantum wires (QWrs) is affected by the P∕As exchange process. In this work, we demonstrate by in situ stress measurements that P∕As exchange at the InAs∕InP interface depends on the surface reconstruction of the InAs starting surface and its immediate evolution when the arsenic cell is closed. Accordingly, the amount of InP grown on InAs by P∕As exchange increases with substrate temperature in a steplike way. These results allow us to engineer the size of the QWr for emission at 1.3 and 1.55 μm at room temperature by selecting the range of substrate temperatures in which the InP cap layer is grown.

Impact de l'épandage des boues sur le phosphore dissous et particulaire des écoulements de surface

2003

Abstract The aim of this study was to assess the effect of land application of sewage sludge on phosphorus (P) losses during intense rainfall. Three rainfall simulations (40 mm h−1 of 30 min duration) were conducted on a field amended with sewage sludge. The overland flow water (OFW) was monitored and sampled every minute. The suspended solid, the dissolved and total phosphorus (respectively SS, TP and DP) concentrations were analysed. The forms of particulate bound P (PP) were investigated. Several results stem from this experiment: (a) sludge application induced a large increase in the DP content of the OFW; the concentrations obtained (0.15–0.57 mg l−1) were shown to result from desorpti…

Bacillus consortium positively impacts arbuscular mycorrhizal fungi community, plant phosphate nutrition and potato yield in Solanum tuberosum cv. Ja…

2022

Many agricultural soils are naturally poor in plant available phosphorus (P), although total P stocks can exceed plant requirements by more than 100-fold. The reason for such apparent contradiction is that P is complexed under organic and inorganic forms, but only free inorganic orthophosphate (Pi) ions are available to plants and soil organisms. The high immobility of Pi in soil, the low soil solution circulation associated with a rapid root absorption lead to the development of a depletion zone around the roots. As a consequence, P is frequently a limiting factor for plant growth and development.Arbuscular mycorrhizal (AM) fungi are estimated to colonize the vast majority of crop plants a…

Phosphorus tolerance of an hypermycorrhizal mutant of Medicago truncatula

2010

International audience

Unusual activity pattern of leucine aminopeptidase inhibitors based on phosphorus containing derivatives of methionine and norleucine

2010

Ligands containing bulky aliphatic P1 residues exhibit a high affinity towards cytosolic leucine aminopeptidase, a bizinc protease of biomedical significance. According to this specificity, a series of phosphonic and phosphinic compounds have been put forward as novel putative inhibitors of the enzyme. These phosphonic and phosphinic compounds were derivatives of methionine and norleucine as both single amino acids and dipeptides. The designed inhibitors were synthesised and tested towards the peptidase isolated from porcine kidneys using an improved separation procedure affording superior homogeneity. Unexpectedly, organophosphorus derivatives of methionine and norleucine exhibited moderat…

Synthesis of fluorescent (benzyloxycarbonylamino)(aryl)methylphosphonates

2014

The synthesis of a library of structurally variable aromatic esters of (benzyloxycarbonylamino)(aryl)methylphosphonic acids is described by means of the Oleksyszyn reaction. The library was enlarged by the application of a Suzuki–Miayra approach and by preparation of mixed esters.

OZNACZANIE ZWIĄZKÓW FOSFORU W MATRYCACH ROŚLINNYCH

2021

The variety of the chemical forms of phosphorus compounds occurring in plant tissues, accompanied by the complexity of the chemical composition of plants as the analytical matrices, are the reasons why there is no one, the best answer, how those individual substances may be determined qualitatively and quantitatively. Interestingly, if the subject of determination is the total phosphorus content, the spectrum of effective methods and techniques seems to be impressive. However, in case of spectrophotometric measurements and classical variants of absorption (FAAS) or emission (ICP-AES/ ICP-OES) spectrometry techniques, it is necessary at first to isolate various phosphorus forms from the matr…

Isolation of organophosphorus-degrading bacteria from agricultural mediterranean soils

2010

Mycorrhizal benefit differs among the sexes in a gynodioecious species

2010

Both plant sex and arbuscular mycorrhizal (AM) symbiosis influence resource acquisition and allocation in plants, but the interaction between these two components is not well established. As the different plant sexes differ in their resource needs and allocation patterns, it is logical to presume that they might differ in their relationship with AM as well. We investigate whether the association with AM symbiosis is different according to the host plant sex in the gynodioecious Geranium sylvaticum, of which, besides female and hermaphrodite plants, intermediate plants are also recognized. Specifically, we examine the effects of two different AM fungi in plant mass allocation and phosphorus …