Since ancient times, seaweeds have been employed as source of highly bioactive secondary metabolites that could act as key medicinal components. Furthermore, research into the biological activity of ...certain seaweed compounds has progressed significantly, with an emphasis on their composition and application for human and animal nutrition. Seaweeds have many uses: they are consumed as fodder, and have been used in medicines, cosmetics, energy, fertilizers, and industrial agar and alginate biosynthesis. The beneficial effects of seaweed are mostly due to the presence of minerals, vitamins, phenols, polysaccharides, and sterols, as well as several other bioactive compounds. These compounds seem to have antioxidant, anti-inflammatory, anti-cancer, antimicrobial, and anti-diabetic activities. Recent advances and limitations for seaweed bioactive as a nutraceutical in terms of bioavailability are explored in order to better comprehend their therapeutic development. To further understand the mechanism of action of seaweed chemicals, more research is needed as is an investigation into their potential usage in pharmaceutical companies and other applications, with the ultimate objective of developing sustainable and healthier products. The objective of this review is to collect information about the role of seaweeds on nutritional, pharmacological, industrial, and biochemical applications, as well as their impact on human health.
This research was carried out in order to demonstrate that mulching the ground helps to conserve water, because agricultural sustainability in dryland contexts is threatened by drought, heat stress, ...and the injudicious use of scarce water during the cropping season by minimizing surface evaporation. Improving soil moisture conservation is an ongoing priority in crop outputs where water resources are restricted and controlled. One of the reasons for the desire to use less water in agriculture is the rising demand brought on by the world’s growing population. In this study, the use of organic or biodegradable mulches was dominated by organic materials, while inorganic mulches are mostly comprised of plastic-based components. Plastic film, crop straw, gravel, volcanic ash, rock pieces, sand, concrete, paper pellets, and livestock manures are among the materials put on the soil surface. Mulching has several essential applications, including reducing soil water loss and soil erosion, enriching soil fauna, and improving soil properties and nutrient cycling in the soil. It also reduces the pH of the soil, which improves nutrient availability. Mulching reduces soil deterioration by limiting runoff and soil loss, and it increases soil water availability by reducing evaporation, managing soil temperature, or reducing crop irrigation requirements. This review paper extensively discusses the benefits of organic or synthetic mulches for crop production, as well as the uses of mulching in soil and water conservation. As a result, it is very important for farmers to choose mulching rather than synthetic applications.
•A compression–absorption system with alternatives refrigerants is analyzed.•Geothermal sources used for reducing electric energy consumption of refrigeration.•A compression power in cascade cycles ...was 50–55% lower than in compression cycles.•The systems operating with (LiBr-H2O)/R1234yf achieved higher COP.•Comparison of geothermal energy with solar energy in cascade cycle is given.
This study proposes a simulation that incorporates energy, exergy, and economic factors into the development of an absorption-compression cycle for air-conditioning that makes use of heat sources available in Algeria. The springs have been used on record range in temperature between 60 and 94 °C. LiBr-H2O and LiCl-H2O have been used in the absorption section and low global warming potential fluids including R1234yf, R1234ze (E), and R1233zd (E) in the vapor compression section. In using these combinations of fluids, a recorded (51.36–54.16%) decrease in electricity consumption has been documented in comparison with conventional cycles. Furthermore, the coefficient of performance (COP) values for all of the combinations used ranged between (0.432 and 0.659). Enhanced performance was noted in the systems that used (LiBr-H2O/R1234yf). Economically, the use of geothermal energy is more financially sound in comparison to the use of solar energy in depth of well's less than 16 m.
This study aims to produce green zinc oxide nanoparticles (ZnO-NPs) derived from red seaweed (Pterocladia Capillacea) and evaluate their potential to absorb Ismate violet 2R (IV2R) ions from an ...aqueous solution. UV-vis spectrophotometry, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and a Brunauer–Emmett–Teller surface area analysis (BET) were used to analyze the structural, morphological, and optical features of the synthesized nanoparticles. The change in color of the chemical solution revealed the formation of zinc oxide nanoparticles. The FTIR examination confirmed the synthesis of both Zn and ZnO nanoparticle powder, with a BET surface area of 113.751 m2 g−1 and an average pore size of 2.527 nm for the synthesized adsorbent. Furthermore, the maximum removal effectiveness of IV2R was 99% when 0.08 g ZnO-NPs was applied at a pH of 6, a temperature of 55 °C, and a contact time of 120 min. The dye adsorption capacity of the ZnO-NPs was 72.24 mg g−1. The adsorption process was also controlled by the Freundlich adsorption model and pseudo-second-order reaction kinetics. The adsorption of IV2R ions onto the ZnO-NPs could be represented as a nonideal and reversible sorption process of a nonuniform surface, according to Freundlich adsorption isotherms. In addition, the constant values of the model parameters were determined using various nonlinear regression error functions. Moreover, thermodynamic parameters such as entropy change, enthalpy change, and free energy change were investigated; the adsorption process was spontaneous and endothermic. The high capacity of the ZnO-NPs synthesized by red seaweed promotes them as promising substances for applications in water treatment for the removal of IV2R dye from aqueous systems.
Batch adsorption experiments were carried out to study the removal of the toxic Methylene Blue Dye (MBD) from synthetic aqueous solutions using the nanoparticles form of
NIOF17/003. The adsorption ...capacity of the adsorbent for MBD was investigated using different amounts of
nanoparticles at different contact times, temperatures, pH, and MBD initial concentrations in the synthetic aqueous solution. In addition,
nanoparticles were characterized using Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET), Fourier Transform Infrared (FTIR), and Ultraviolet spectra (UV) techniques. The optimum removal of MBD was found at a concentration of 0.4 g
nanoparticles.
nanoparticles remove 93% of MBD in 5 min (under agitation conditions at 150 rpm). The highest adsorption capacity was found by the Langmuir model to be 58.8 mg g
. It is an endothermic process with spontaneity increasing with temperature. The probable mechanism for the adsorption is chemisorption via surface-active charges in the initial phase, which is followed by physical sorption by occupying pores of
. MBD adsorption by
follows pseudo-second-order kinetics. The Freundlich and Langmuir models fit well with the experimental data. The adsorption experiments suggested that the regeneration of the adsorbents was possible for repeated use, especially regarding MBD up to 65.8% after three cycles, which proves it can be easily recycled. In conclusion, the nanoparticles of
have a significant adsorption potential in the removal of MBD from effluent wastewater.
This study aims at investigating worn surface topography and mathematical modeling of annealed Ti-6Al-3Mo-2Sn-2Zr-2Nb-1.5Cr alloy using response surface methodology (RSM). The alloy was subjected to ...three different regimes in order to study their effect on mechanical properties. First regime was applying cold deformation by compression until 15% drop in height at room temperature. The second regime was performing solution treated on the deformed samples at 920 °C for 15 min then air-cooled (AC) to ambient temperature. Third regime was applying aging on the deformed and solution treated specimen for 4 hr at 590 °C followed by air-cooling. Three different velocities (1, 1.5, and 2 m/s) were adopted to conduct dry sliding wear according to the experimental design technique (EDT). Gwyddion and Matlab softwares were used to detect worn surface photographs analytically and graphically. Maximum hardness of 425 HV
was obtained for AC+Aging specimen, while minimum hardness of 353 HV
was reported for the annealed specimen. Applying aging process after solution treatment enhanced considerably the wear property and this enhancement reached 98% as compared to the annealed condition. The relationship between input factors (hardness & velocity) and responses (Abbott Firestone zones) was demonstrated using analysis of variance (ANOVA). The best models for Abbott Firestone zones (high peaks, exploitation, and voids) produced accurate data that could be estimated for saving time and cost. The results showed that the average surface roughness increases with increasing sliding velocity for all conditions except AC+Aging condition where the average surface roughness decreased with increasing sliding velocity. The results revealed that at low velocity and hardness, the material gives the highest exploitation zone (86%). While at high velocity and hardness, the material gives the lowest exploitation zone (70%). In general, the predicted results of mathematical model showed close agreement with experimental results, creating that models could be utilized to predict Abbott Firestone zones satisfactorily.
This study aimed to synthesize, characterize, and explore the eco-friendly and antifungal potential of precocenes and their derivatives. The organic synthesis of the mono-O-alkyl-2,2-dimethyl ...2H-1-chromene series, including the natural product precocene I, and the di-O-alkyl 2,2-dimethyl-2H-1-chromene series, including the natural 2H-1-chromenes precocenes II and III, was achieved. The synthetic compounds were subjected to spectroscopic analysis, 1HNMR,13CNMR, and mass characterization. The antifungal activity of synthesized precocenes I, II, and III, as well as their synthetic intermediates, was evaluated by the poison food technique. Precocene II (EC50 106.8 µg × mL−1 and 4.94 µg mL−1), and its regioisomers 7a (EC50 97.18 µg × mL−1 and 35.30 µg × mL−1) and 7d (EC50 170.58 × µg mL−1), exhibited strong fungitoxic activity against Aspergillus niger and Rhizoctonia solani. Some of the novel chromenes, 11a and 11b, which had never been evaluated before, yielded stronger fungitoxic effects. Finally, docking simulations for compounds with promising fungitoxic activity were subjected to structure–activity relationship analyses against the polygalactouronases and voltage-dependent anion channels. Conclusively, precocenes and their regioisomers demonstrated promising fungitoxic activity; such compounds can be subjected to minor structural modifications to yield promising and novel fungicides.
The energy crisis impact is increasing at all levels and then requires a quick sustainable and robust response. The last two decades have witnessed huge efforts to find solutions that can be ...classified within two classes: renewable energy and energy recovery. Abundant researches have been dedicated to find carbon dioxide-free energy sources. Fuel Cell (FC) is one of the most promising solutions. It is fed by hydrogen and generates electricity without any carbon dioxide emissions. The hydrogen is supplied by an electrolyzer that requires an electrical current to decompose the water into hydrogen and oxygen. This paper aims at proposing a coupled system of hydrogen and solar energy. The solar thermal system is used as an energy source to supply the electrolyzer. The modeling of the FC and the Thermal Solar System (TSS) are comprehensively presented. A case study for a stand-alone system that supplies 3 kW in Beirut City is studied. Through the simulation results, the power over the year as well as the relevant number of mirrors needed to cover the power demand are properly calculated. For instance, 80 mirrors are needed in August 1st to provide 3 kW whereas 367 mirrors are required to provide the same load in January 1st.
•A modeling of hybrid system coupling fuel cell and solar thermal system is proposed.•The model allows to size the complete system in terms of the different parameters of the fuel cell and the solar system.•The model can be used as tool to size, analyze or predict the behavior of the system for different regions or time period.•A case study on the city of Beirut is presented.
Implementing the deficit irrigation pattern has become a major strategy in crop production systems. However, using less water than is required to irrigate crops is associated with changes in plant ...physiology and lower productivity. Therefore, the current research aimed to assess the integrated effect of humic acid and cytokinin on faba bean under water deficit. Under two irrigation levels (full irrigation, FI and deficit irrigation, DI), two humic acid treatments (without addition, H0 and with addition of 10 kg ha−1, H10) and two cytokinin concentrations (without spray, C0 and spraying with 25 mg L−1, C25), faba bean growth, physiology, and productivity were evaluated. The experiment was implemented for two winter seasons of 2019/20 and 2020/21 and performed in a split–split plots design with three replicates. The findings revealed that under low water supply (DI), H10 plus C25 was the most efficient treatment for enhancing faba bean growth. All physiological faba bean traits estimated under DI showed remarkable increases with the application of H10 plus C25 in both seasons. The increases in proline, catalase, and total soluble sugars under DI due to H10 plus C25 were 31.4 and 31.8%, 51.9 and 55.1% as well as 43.8 and 46.6%, in the first and second seasons, respectively. There was no significant difference between FI × H10 plus C25 and DI × H10 plus C25 in phosphorus content in both seasons. FI × H10 plus C25 and DI × H10 plus C25 in the second season produced a similar number of pods plant−1 and seed yield of faba bean. Conclusively, the combined application of humic plus cytokinin achieved physiological and nutrient homeostasis, adjusting the biochemical compounds in faba bean under water deficit.
In the current study, we investigated the effect of potassium humate (Kh) and salicylic acid (SA) in mitigating the salinity stress of common bean plants. Common bean seedlings were treated with 0.2 ...g/L SA as a foliar application and 0.3 g/L Kh as a soil application individually or in combination. After 7 days of germination, plants were treated with 50 mM NaCl and normal water as a control. Our results indicate that salt treatment reduced the plant growth (fresh and dry shoots and roots), leaf pigments (total chlorophyll and carotenoids), ascorbic acid (AA), glutathione (GSH), and potassium (K) contents. On the contrary, proline content; sodium (Na); hydrogen peroxide (H
O
); superoxide anion (O
); and antioxidant enzymes, including catalase (CAT), peroxidase (POX), and superoxide dismutase (SOD), were increased by saline stress. However, applying either individual Kh and SA or their combination stimulated seedling growth under salinity stress by increasing growth parameters, leaf pigment contents, AA, GSH, proline content, K content, and antioxidant enzymes compared with the control. Additionally, Na content, H
O
, and O
were reduced by all applications. The application of the Kh (0.3 g/L) + SA (0.2 g/L) combination was more effective than using the individual compounds. In conclusion, applications of Kh + SA can mitigate salt stress and improve the seedling growth of common bean.
