Assessment of phosphogypsum use in a nursery for plant propagation

Phosphogypsum (PG) was used as substrate for the multiplication of eight ornamental species; six by cuttings and two by sowing. The results obtained showed a high rooting or percent germination for the six plants: Ficus benjamina, Pelargonium × Hortorum, Washingtonia filifera, Eucalyptus camaldulensis, Hibiscus rosa sinensis and Acalypha wilkesiana. For a percentage of 50% PG, only F. benjamina, H. rosa sinensis and W. filifera showed high percentage rooting. Plant vigour (height and biomass) depends on both species and treatment. Two species showed high sensitivity to PG during the propagation by cuttings, Nerium oleander and Myoporum laetum. We observed high variation in substrate characteristics; with 50% PG, pH was increased from 2.84 to 6.22, and electrical conductivity (EC) and gypsum concentration were reduced from 15.56 to 4.23 mS/cm from 36.23 to 11.82%, respectively. The results showed the possibility of using PG in nurseries for the multiplication and fertilization of several forest and ornamental plant species by cuttings and sowing.     

Multivariate Data Analysis of Fatty Acid Content in the Classification of Olive Oils Developed Through Controlled Crossbreeding

The fatty acid (FA) composition of 540 Tunisian virgin olive oil hybrids (VOO) were classified by principal component analysis (PCA). Pearson correlation between FA variables revealed an inverse association between C18:1 and C18:2; C18:1 and C16:0, while C16:0 and C16:1 were positively correlated. PCA yielded five significant PCs, which together account for 79.95% of the total variance; with PC1 contributing 36.84% of the total. Eigenvalue analysis revealed that PC1 was mainly attributed to C18:1, monounsaturated fatty acids (MUFA) and the ratios oleic/linoleic (O/L) and monounsaturated fatty acids/polyunsaturated fatty acids (MUFA/PUFA); PC2, by C16:0, saturated fatty acids (SFA) and the palmitic/linoleic ratio (P/L); PC3 by C18:2 and C22:0, PC4 by C18:0 and PC5, by C17:1. Then, PCA analysis indicated that in addition to C16:0, C18:0, C18:1, C17:1, and C22:0, MUFA, SFA and the ratios O/L, P/L and MUFA/PUFA were determined to be the main factors responsible for the olive oil hybrids discrimination.     

Enantiomeric and non-enantiomeric monoterpenes of Juniperus communis L. and Juniperus oxycedrus needles and berries determined by HS-SPME and enantioselective GC/MS

For the first time, enantiomeric and non-enantiomeric distribution of monoterpenes in the headspace of Juniperus communis L. and Juniperus oxycedrus needles and berries has been determined using HS-SPME combined with enantioselective GC/MS. The essential oils from needles and berries of both Juniperus species obtained by hydrodistillation were also performed. HS-SPME has shown good potential to reproduce the same results as the commonly used hydrodistillation extraction technique. While needles and berries of J. communis showed high contents of sabinene, α-pinene and β-myrcene with 19-30%, 12-24% and 9-20%, respectively, J. oxycedrus was strongly dominated by α-pinene with 85-92% in both needles and berries. Large variations in chiral distribution of monoterpenes within the same plant species and between the two junipers were observed. Interestingly, similar enantiomeric preferences of monoterpenes were obtained between needles and berries of the two junipers.     

Positive contrast with therapeutic iron nanoparticles at 4.7 T

Object  

The purpose of the study was to show the feasibility of a positive contrast technique GRadient echo Acquisition for Superparamagnetic particles with Positive contrast (GRASP), for a specific type of magnetic particles, designed for tumor treatment under MRI monitoring.     

Preparation of a New Polystyrene Supported-Ethylenediaminediacetic Acid Resin and its Sorption Behavior toward Divalent Metal Ions

A new polystyrene-supported ethylenediaminediacetic acid resin has been synthesized through a reaction between the amination of the commercially available 4-chloromethyl polystyrene polymer with ethylenediamine and the subsequent carboxymethylation with monobromoacetic acid, using ethylenediamine as spacer. The chelation behavior of this resin toward the divalent metal ions Cu²⁺, Ni²⁺, Zn²⁺, and Pb²⁺ in aqueous solutions was investigated. Batch equilibration experiments were carried out as a function of contact time, pH, amount of metal-ion, and polymer mass. The amount of metal-ion uptake of the polymer was determined by using atomic absorption spectrometry (AAS). Results of the investigation revealed that the resin exhibited higher capacities and a more pronounced adsorption toward Cu²⁺ and that the metal-ion uptake follows the order: Cu²⁺ > Zn²⁺ > Ni²⁺ > Pb²⁺. The adsorption and binding capacity of the resin toward the various metal ions investigated are discussed.     

Electrochemical removal of phenol in alkaline solution. Contribution of the anodic polymerization on different electrode materials

The removal of organic pollutants based on electropolymerization on an anode was performed in the case of phenol in alkaline solution. The polymer formed by a process involving less than two electrons per molecule of phenol, is then precipitated by decreasing the pH and finally filtered and disposed. The electrochemical polymerization of phenol (C₀ = 0.105 M) in alkaline solution (pH = 13) at 86 °C has been studied by galvanostatic electrolysis, using a range of anode materials characterized by different O₂-overpotentials (IrO₂, Pt and β-PbO₂). Measurements of total organic carbon and HPLC have been used to follow phenol oxidation; the morphology of the polymer deposited on the electrode surface has been examined by SEM. Experimental data indicate that phenol concentration decreases by oxidation according to a first order reaction suggesting a mass transport limitation process. Polymeric films formed in alkaline solution did not cause the complete deactivation of the anodes. SEM results show that the polymeric films formed on Ti/IrO₂ and Pt anodes cannot be mineralized. On the other hand, complex oxidation reactions leading to the partial incineration of polymeric materials can take place on the Ta/β-PbO₂ surface due to electrogenerated HO radicals which have an oxidizing power much higher than that of intermediaries formed respectively on IrO₂ and Pt. It is assumed that the polymer films formed on these anodes have different permeability characteristics which determine the rate of mass transfer of the phenol. The fractions of phenol converted in polymers were 25, 32 and 39% respectively with Ti/IrO₂, Pt and Ta/β-PbO₂, a series of materials in which the O₂-overvoltage increases.     

Simulators for medical training: application to vascular ultrasound imaging

Whilst computers are more and more used in the medical and surgical domains, medical education is still very conservative. However, new information technology could bring a lot to this area. In particular, simulators are of paramount interest: they would allow one both to experiment with surgical or imaging techniques for a wide range of pathologies without the need for patients and to quantitatively evaluate the trainees' performances. Ultrasound imaging is a typical area where virtual reality may change educational uses. This paper describes an ultrasound imaging simulator dedicated to the training of physicians for the detection of deep venous thromboses of the lower limbs. Like this one, a lot of other pathologies of soft tissue are diagnosed using ultrasound imaging. Because this examination is difficult and operator‐dependent, developing a simulator is very useful to give common databases of pathological samples on which physicians can both experiment with image acquisition and evaluate their understanding of clinical cases. Real‐time simulation is mandatory. An ultrasound imaging simulator has been developed and is being tested. This paper presents the hardware and software components of the simulator and describes the status of this project. Copyright © 2000 John Wiley & Sons, Ltd.