Search results for "bulk"
showing 10 items of 286 documents
Seasonal fluctuations and long-term persistence of pathogenic populations of Agrobacterium spp. in soils.
2002
ABSTRACT Short- and long-term persistence of pathogenic (i.e., tumor forming) agrobacteria in soil was investigated in six nursery plots with a history of high crown gall incidence. No pathogenic Agrobacterium strains were isolated in soil samples taken in fall and winter in any plots, but such strains were isolated from both bulk soils and weed rhizospheres (over 0.5 × 10 5 pathogenic CFU/g of bulk soil or rhizosphere) in three out of six plots in spring and summer. PCR amplifications of a vir sequence from DNA extracted from soil confirmed the presence of Ti plasmids in summer and their absence in fall and winter. The results indicate that strains that harbor a Ti plasmid had an unforesee…
Synthesis of oligomers and polymers doped with porphyrins for solar energy conversion
2017
The aim of this thesis was to elaborate new electron donor materials for organic solarcells. This emerging photovoltaic technology is rapidly expanding, and has yet already reached the limit for its large-scale commercialization. The low manufacturing cost of organic photovoltaic devices make then competitive face to well-established inorganic technologies. Their biggest advantage is their weight and their mechanical properties which make them flexible. They should play a key role in future as a complement to classic solar cells, with their use in specific applications. We developed polymers by using different chomophores, well-known for their interesting photophysical properties: the porph…
Effect of cropping cycles and repeated herbicide applications on the degradation of diclofop-methyl, bentazone, diuron, isoproturon and pendimethalin…
2002
A greenhouse study was conducted to investigate the ability of four crops (wheat, corn, oilseed rape and soybean) to influence the degradation of bentazone, diclofop-methyl, diuron, isoproturon and pendimethalin in soil. The present study showed that microbial biomass-carbon was significantly higher in planted soils than in bulk soil, especially with wheat and corn, after several cropping cycles. The biomass in corn and soybean planted soils was adversely affected by bentazone but recovered after three cropping cycles. In wheat-planted soils, diclofop-methyl application resulted in persistent increase of the amount of microbial biomass. Bentazone did not show accelerated degradation even af…
Medicago species affect the community composition of arbuscular mycorrhizal fungi associated with roots
2007
National audience; The symbiosis between plants and arbuscular mycorrhizal fungi (AMF) is ancient and involves 80% of terrestrial plant families. The symbiotic association between AMF and plants was described to be non specific. However, AMF were reported to influence plant community diversity and productivity. On the other way, the effect of plant genotypes belonging to closely related species on AMF diversity has not been explored so far. The aim of this work was to assess the impact of four different Medicago species, M. laciniata, M. murex, M. polymorpha and M. truncatula cv. Jemalong J5, on the composition of AM fungal community, when cultivated in a silty-thin clay soil (Mas d’Imbert,…
Transparent boundary condition for acoustic propagation in duct with bulk-reacting liner
2012
International audience; The proposed study focuses on the modeling of acoustic wave propagation in infinite guides lined with bulk-reacting sound absorbing material which allows acoustic propagation through the lining. The finite element method is used, it is then necessary to limit the numerical domain by an artificial boundary on which a transparent boundary condition is introduced. The method described in this work consist to write the transparent condition as a Dirichlet to Neumann operator (DTN) based on a modal decomposition of the pressure in the guide. This study is a generalization of recent works with absorbent materials modeled with impedances boundary condition. The presented me…
Tackling Performance Challenges in Organic Photovoltaics: An Overview about Compatibilizers
2020
Organic Photovoltaics (OPVs) based on Bulk Heterojunction (BHJ) blends are a mature technology. Having started their intensive development two decades ago, their low cost, processability and flexibility rapidly funneled the interest of the scientific community, searching for new solutions to expand solar photovoltaics market and promote sustainable development. However, their robust implementation is hampered by some issues, concerning the choice of the donor/acceptor materials, the device thermal/photo-stability, and, last but not least, their morphology. Indeed, the morphological profile of BHJs has a strong impact over charge generation, collection, and recombination processes; control o…
Major ions and trace elements composition of rainwater around the two industrial areas of Milazzo and Priolo Gargallo (Sicily - Italy)
2023
This database shows the concentration of major ions and trace elements in rainwater from two polluted industrial areas of Sicily, Milazzo and Priolo Gargallo, collected from June 2018 to July 2019, through a network of 11 bulk collectors to sample bulk atmospheric deposition, for a total of 131 samples collected. Different sources, both natural and anthropogenic, for both major ions and trace elements have been recognised. This study also highlighted some critical issues with common methods of sampling and analysing atmospheric deposition. The analysis and comparison of two different aliquots, filtered and unfiltered rainwater, has shown that the filtration method removes from the sample a …
Impact Assessment of Skidding Extraction: Effects on Physical and Chemical Properties of Forest Soils and on Maple Seedling Growing along the Skid Tr…
2019
Several studies investigated soil disturbances caused on skid trails by forest logging. However, there is still a lack of knowledge about the severity and the distance of disturbances along both sides from the trails. The aims of this study were: i) to investigate the changes in physical and chemical properties of soil along the sides of skidding trails
Janus Nanostructures from ABC/B Triblock Terpolymer Blends
2019
Lamella-forming ABC triblock terpolymers are convenient building blocks for the synthesis of soft Janus nanoparticles (JNPs) by crosslinking the B domain that is &ldquo
The impact of the age of vines on soil hydraulic conductivity in vineyards in eastern Spain
2017
Soil infiltration processes manage runoff generation, which in turn affects soil erosion. There is limited information on infiltration rates. In this study, the impact of vine age on soil bulk density (BD) and hydraulic conductivity (Ks) was assessed on a loam soil tilled by chisel plough. Soil sampling was conducted in the inter row area of six vineyards, which differed by the age from planting: 0 (Age 0; just planted), 1, 3, 6, 13, and 25 years (Age 1, Age 3, Age 6, Age 13, and Age 25, respectively). The One Ponding Depth (OPD) approach was applied to ring infiltration data to estimate soil Ks with an α* parameter equal to 0.012 mm-1. Soil bulk density for Age 0 was about 1.5 times greate…