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Nanocomposite of polyvinyl chloride (PVC)/polyvinylidene fluoride (PVDF) have been in situ synthesized. Copper oxide nanoparticles (CuONPs) have been prepared via using the laser ablation technique. Nanoparticles were added to the blend. The properties of the blend were studied before and after adding CuONPs. These properties were characterized by different techniques. Antimicrobial activity of the prepared nanocomposite film was investigated. FTIR data show vibrational spectral bands and the shift of the bands is related to the interaction and the complexation that occurs between blend and nanoparticles. Structural properties and crystallinity of the samples were investigated using XRD diffraction. XRD results illustrated the effect of CuONPs at two new peaks 2θ = 26.25º and 38.41º. These results confirmed the interaction CuO NPs and PVDF/PVC matrix. UV–Visible analyses confirmed the existing of copper oxide nanoparticles and were also used for determining the optical absorption edge. The absorption edges have been obtained at 430–520 nm for all of the doping films. The obtained values for indirect and direct bandgaps were reduced by raising the nanoparticles because of the presence of charge transfer between PVC/PVDF and CuONPs. SEM images illustrateed the presence of CuONPs on the surface of the blend and the morphology changes which occurred to the blend. The antibacterial activity for the nanocomposite proved the antimicrobial effect of copper oxide nanoparticles. The prepared PVC/PVDF/CuONPs are potentially suggesting to be applied for biomedical applications. [ABSTRACT FROM AUTHOR]

Nanocomposite films of (30% PVC/70% PVDF) blend containing silver nanoparticles were synthesized via pulsed laser ablation route (PLA). Changes in physical characterization of PVC/PVDF blend before and after the incorporation of AgNPs have been studied. FTIR results confirms the interaction between AgNPs and PVC/PVDF. XRD results obtain the existence of peak at 38.42̊ in sample PVC/PVDF/Ag4 which confirm the embedded AgNPs in the high concentration. SEM photos confirm the distribution of silver nanoparticles on the surface of the sample in spherical shape which approved the dispersion of silver nanoparticles in PVC/PVDF blend. The inhibitory zone diameters observed for PVC/PVDF/Ag4 against Escherichia coli, Klebsiella pneumonia, Staphylococcus aureus, and Bacillus cereus were recorded as 11 ± 1, 10 ± 1, 15.7 ± 0.6, and 17.7 ± 0.6, respectively. PVC/PVDF/AgNPs nanocomposite film could be suggested for biomedical applications such as wound healing products. [ABSTRACT FROM AUTHOR]

The wheat is strongly attaked by Septoria leaf blotch disease caused by Mycosphaerella graminicola (anamorph = Septoria tritici) in Algeria. This pathogen has been very damaging in recent decades, can reduce yields by more than 60%. However, any of all of the previous studies, never indicates the presence of the teleomorph M. graminicola in Algeria, the main source of variability of the pathogen. Also, in a first approach the phenotypic diversity of this pathogen has focused on a collection of 27 isolates which 23 are from durum wheat and 4 from soft wheat. These 27 isolates are obtained from the central regions (Mitidja, Kabylie) and Eastern Region (Constantine, Annaba). The results show a cultural, morphological and pathological variability of isolates. In the second part, confrontations of isolates are made in pairs and allowed for two couples to getting pseudothecia that indicating the existence of two compatible mating types in Algeria required for the formation of the teleomorph. These results imply the possibility of sexual reproduction in cultures, something that has never been observed to date in Algeria. [ABSTRACT FROM AUTHOR]

The article presents a study on early blight that is caused by Alternaria linariae on potato in a farm in Algeria.

Polyvinyl acetate nanocomposites were successfully prepared based on silver nanoparticles. First, silver nanoparticles were directly prepared during the in situ emulsion polymerization of vinyl acetate monomer using AgNO3as a source of Ag+ions and poly(vinyl alcohol) was used for dual functions as emulsifier for emulsion polymerization and as a stabilizing agent, trisodium citrate (C6H5O7Na3) was used as reducing agent for Ag+ions during the polymerization process. The prepared polyvinyl acetate/Ag nanocomposites were assessed using X-ray diffraction, scanning electron microscopy, Fourier transform infrared, transmission electron microscopy, and ultraviolet spectra. The antibacterial properties of the prepared polyvinyl acetate/Ag nanocomposites were investigated as antimicrobial activity against pathogenic bacteria, i.e.,Staphylococcus aureus(G+vebacteria) andEscherichia coli(G−vebacteria). These polyvinyl acetate nanocomposites could be used as a promising material for enhanced and continuous antibacterial applications as coating and packaging materials. [ABSTRACT FROM PUBLISHER]