7 research outputs found
Olive agroforestry shapes rhizosphere microbiome networks associated with annual crops and impacts the biomass production under low-rainfed conditions
Agroforestry (AF) is a promising land-use system to mitigate water deficiency, particularly in semi-arid areas. However, the belowground microbes associated with crops below trees remain seldom addressed. This study aimed at elucidating the effects of olive AF system intercropped with durum wheat (Dw), barely (Ba), chickpea (Cp), or faba bean (Fb) on crops biomass and their soil-rhizosphere microbial networks as compared to conventional full sun cropping (SC) under rainfed conditions. To test the hypothesis, we compared the prokaryotic and the fungal communities inhabiting the rhizosphere of two cereals and legumes grown either in AF or SC. We determined the most suitable annual crop species in AF under low-rainfed conditions. Moreover, to deepen our understanding of the rhizosphere network dynamics of annual crops under AF and SC systems, we characterized the microbial hubs that are most likely responsible for modifying the microbial community structure and the variability of crop biomass of each species. Herein, we found that cereals produced significantly more above-ground biomass than legumes following in descending order: Ba > Dw > Cp > Fb, suggesting that crop species play a significant role in improving soil water use and that cereals are well-suited to rainfed conditions within both types of agrosystems. The type of agrosystem shapes crop microbiomes with the only marginal influence of host selection. However, more relevant was to unveil those crops recruits specific bacterial and fungal taxa from the olive-belowground communities. Of the selected soil physicochemical properties, organic matter was the principal driver in shaping the soil microbial structure in the AF system. The co-occurrence network analyses indicated that the AF system generates higher ecological stability than the SC system under stressful climate conditions. Furthermore, legumes’ rhizosphere microbiome possessed a higher resilient capacity than cereals. We also identified different fungal keystones involved in litter decomposition and drought tolerance within AF systems facing the water-scarce condition and promoting crop production within the SC system. Overall, we showed that AF reduces cereal and legume rhizosphere microbial diversity, enhances network complexity, and leads to more stable beneficial microbial communities, especially in severe drought, thus providing more accurate predictions to preserve soil diversity under unfavorable environmental conditions.This research was carried out as part of the D4DECLIC Project, ARIMNet 2 Young Scientists Call 2017 (ERA-NET program), and Grant agreement no. 618127
Importance of the radiations in water splitting for hydrogen generation
The review article examines the production of molecular hydrogen from the decomposition of water by various irradiation methods. The article shows different types of radiation: UV radiation, visible radiation, gamma radiation, X-ray radiation and neutron radiation. Electrons generated by radiation inside a nanoparticle of radius R suspense in fluid water are diffused with equal probability in all directions inside the particle and gradually lose their kinetic energy as a result of elastic and inelastic collisions. Some of these electrons are transported to the nanoparticle surface during the physical and physicochemical stages of the process and emitted into the water. It is extremely important for the formation of nanostructured materials after exposure to ordered nanostructure from the new phase with a period of a few nanometers, promoting the preservation of the properties of materials under high irradiation
Critical role of NiO support morphology for high activity of Au/NiO nanocatalysts in CO oxidation
Summary: The effect on catalytic behavior induced by different morphology of NiO supports has been investigated using the example of gold-catalyzed CO oxidation. Three NiO-supported nanogold consisting of nanogold deposited onto NiO nanorods (NiO-R), nanosheet (NiO-S), and nanodiscs (NiO-D) were prepared. Transmission electron microscopy(TEM)/Scanning transmission electron microscopy(STEM) investigations indicated that Au particles dominantly exposed Au(111) facets virtually independent of NiO architectures. Au/NiO-S displayed a normal Arrhenius-type behavior. Au/NiO-R and Au/NiO-D showed an atypical behavior, characterized by a U-shaped curve of activity vs. temperature, which is attributed to the carbonate accumulation on whose catalytically active sites. On Au/NiO-R, a stable CO-conversion rate of 1.78 molCO gAu−1 h−1 at 30°C was achieved, which is among the higher rates reported so far for supported Au-based systems. DRIFTS measurement identified Auδ+ species as crucial CO adsorption sites promoting CO oxidation, and the catalytic CO oxidation should obey Mars-van Krevelen (240°C)
Simulating two Algerian cities' desalination plants coupled with solar energy systems using TRNSYS
Our study aimed to design a prototype for a desalination unit coupled with a solar collector, utilizing TRNSYS 16, to address the needs of both Bouzaréah in northern Algeria and Ghardaïa in southern Algeria. The desalination unit is composed of vacuum membrane distillation (VMD) coupled with a solar collector, and the photovoltaic has been designed according to the climatic conditions of each region. In this work, the approach adopted is to integrate a model developed in the literature into a simulation environment (TRNSYS) coupled with the CODE-BLOCKS compiler and FORTRAN programming language to create a new component (i.e., VMD process). Simulation results showed that the optimum permeation flux obtained through the desalination unit is relatively higher in Ghardaïa than in Bouzaréah, with a flow exceeding 30 kg/h.m2. The permeation flux and the power to load reached their maximum values with the charge of solar irradiation 48 kg/h.m2 and 6300 kJ/h, respectively, for Ghardaïa at the sun irradiation value 800 W/m2 and temperature of 34 °C. Results showed that Ghardaïa had a higher GOR value than Bouzaréah over the year (10.947 vs. 8.3389). Moreover, both locations recorded thermal recovery ratio values exceeding 1, indicating the high efficiency of the desalination unit.
HIGHLIGHTS
A model that describes the evolution of feed temperature and permeation flux through the membrane was integrated into TRNSYS as a VMD module.;
Empirical correlations were developed based on experimental results recorded at a meteorological station in two different cities.;
The plant was designed to conduct annual simulations in two different cities under specific operating conditions.
Anchoring of carboxyl-functionalized porphyrins on MgO, TiO2, and Co3O4 nanoparticles
Hybrid materials consisting of functional organic molecules on metal oxide nanomaterials are key components in emerging technologies, for example in energy conversion and molecular electronics. In this work, we present the results of a comparative study of carboxyl-functionalized porphyrins on different oxide nanomaterials. Specifically, we investigated the interaction of 5(3-carboxyphenyl)-10,15,20-triphenyl-21,23H-porphyrin (2H-3-MCTPP) and 5(4-carboxyphenyl)-10,15,20-triphenyl-21,23H-porphyrin (2H-4-MCTPP), on MgO, TiO2, and Co3O4 nanoparticles (NPs) using isothermal and temperature-programmed diffuse reflection infrared Fourier transform spectroscopy (DRIFTS). We show that both porphyrins bind to the NPs, yielding stable monolayer films consisting of tilted surface carboxylates. In all cases, anchoring through the carboxylic acid group suppresses self-metalation of the porphyrin unit. Upon annealing, all anchored porphyrin films undergo metalation. The position of the acid group has no major influence on the reactivity. The same is true for the nature of the metal oxide, suggesting that the observed behaviour is general for most anchored porphyrin films on oxide nanomaterials