
The present study investigated the effects of different phenol concentrations (200 – 1000 mg L−1) towards Chlorella sp. under different culture conditions (light vs. dark) and NaNO3 concentrations (0 – 0.1 g L−1) using central composite design. Phenol induced hormesis effects on the algal growth and cellular metabolites. Nitrate was identified as a crucial factor for promoting the uptake of phenol by Chlorella cells, while light was a limiting factor for growth, but the phyco-toxicity of phenol was decreased in the dark. The pigment contents were generally increased in the treated cells to protect against the oxidative phenol stress. The incorporation of 200 mg L−1 phenol and 0.05 g L−1 NaNO3 to the illuminated cells markedly promoted biomass and lipid contents to 0.22 g L−1 and 26.26% w/w, which was 44 and 112% higher than the phenol-less control, respectively. Under the same conditions, the increase of phenol concentration to 600 mg L−1, the protein contents were increased to 18.59% w/w. Conversely, the algal cells were able to accumulate more than 60% w/w of soluble carbohydrates under dark conditions at 600 mg L−1 of phenol. Nitrate replete conditions stimulated lipid accumulation at the expense of protein biosynthesis. Furthermore, most of the treatments showed an increase of H2O2 and malonaldehyde contents, especially for the illuminated cells. However, catalase activity tended to increase under dark conditions, especially at low phenol and nitrate concentrations. This study is valuable in indicating the effects of phenol on microalgae by exploiting response surface methodology, which can be applied as a powerful tool in growth monitoring and toxicity assessment.
The marine algal biomass of Ulva lactuca was utilized for the extraction of cellulose and the development of cellulose nanocrystals/graphene oxide film. Cellulose nanocrystals with 50–150 nm were produced by H2SO4 hydrolysis of the algal cellulose. The adsorption efficiency of the nanocomposite film for Fe(II) and Fe(III) ions was successfully evaluated using Box-Behnken design. The maximum removal for Fe(II) (64.15%) could be attained at pH 5.13, adsorbent dosage 7.93 g L−1 and Fe(II) concentration 15.39 mg L−1, while the biosorption of Fe(III) was 69.92% at pH 5.0, adsorbent dosage 2 g L−1, and Fe(III) concentration 15.0 mg L−1. However, in the binary system, the removal efficiency of Fe(II) was enhanced to 95.48% at Fe(II):Fe(III) ratio of 1:1, while the Fe(III) removal was increased to 79.17% at ratio 1:2. The pseudo-second-order kinetics exhibited better fitting to the experimental results of Fe(II) and Fe(III) adsorption in both single and binary systems. The intra-particle diffusion was prominent during the biosorption, but the effect of the external mass transfer was significant. The Langmuir, Freundlich, Langmuir–Freundlich, Temkin, and Dubinin-Radushkevich isotherms showed satisfactory fitting to the experimental data, but they differ in priority based on iron state and pH. The adsorption of Fe(II) in the presence of Fe(III) in a mixture was best represented by the extended Langmuir model, while the extended Langmuir–Freundlich model best fitted the adsorption of Fe(III). The FT-IR analysis indicated that physisorption through electrostatic interaction/complexation is the predominant mechanism for the adsorption of iron using the nanocomposite film.
There is a growing interest in the development of biodegradable hydrogels for the alleviation of drought stress on plants. A novel hydrogel based on brown algal-derived alginate and wastepaper was developed and tested as a soil supplement for sunflower growth under moderate (75% field capacity (FC)) and extreme (50% FC) water-deficit stress. The hydrogel showed fast swelling in water, which obeyed the pseudo-first order kinetics. Besides, it increased the water holding capacity of the soil and exhibited a good phosphate adsorption (37 mg PO4− g−1 hydrogel after 6 days) in the soil, and more than 67% of the adsorbed phosphate was desorbed after 20 days. Thus, the phosphate leaching from the hydrogel-amended soil in a column experiment was only 2.77 mg after 4 times of over-irrigation, compared to 11.91 mg without the hydrogel. The hydrogel application promoted various root traits such as fresh and dry biomass, area, and length by > 2-, > 1.6-, > 1.35-, and > 1.3-folds under both water regimes in relation to the no-hydrogel treatments at the same conditions. Furthermore, the sunflower shoots exhibited similar proline contents to the well-watered control (100% FC), with > 50% reduction in relation to the drought-stressed plants under the same conditions. Similarly, the malondialdehyde contents were lowered by > 15%. The analysis of the antioxidant enzymes also indicated a marked reduction in the specific activities of catalase and ascorbate peroxidase under both 75 and 50% FC compared to the respective controls. Additionally, the hydrogel promoted the uptake of phosphate by sunflower roots. These results implied that the developed biodegradable hydrogel could be effectively applied as a soil additive to alleviate drought stress on crops.
The new mercuric complex [Hg(HL)2Cl2] incorporating salicylaldimine ligand (HL = 2‐((pyridin‐3‐ylimino)methyl)phenol) was fabricated where the ligand molecules behaved in a monodentate manner via their pyridine nitrogen atoms. In addition to elemental characterization, X‐ray crystallographic studies of the complex revealed its packing in a monoclinic crystal system (space group: I2/a, a = 13.4276(2) Å, b = 6.20950(10) Å, c = 27.7530 (4) Å, α = γ = 90°, and β = 98.1610(10)°). Hydrothermal treatment of [Hg(HL)2Cl2] with thioacetamide afforded HgS microparticles (HgS μPs; Brunauer–Emmett–Teller [BET] surface area = 6.205 m2/g, diameter = 196.53–259.13 nm, and average size = 213.27 nm), whereas these microparticles were transformed to nanoscaled HgS particles (HgS NPs; BET surface area = 14.380 m2/g, diameter = 58.87–90.56 nm, and average size = 72.78 nm) by the action of ultrasonication. The as‐prepared HgS, HgS NPs in particular, afforded remarkable microbicidal activity against eight strains of filamentous and unicellular human pathogenic fungi and yeasts in comparison with cycloheximide. Remarkably, Aspergillus terreus grew up to 34.7 ± 1.88 mm in the absence of any fungicide, but HgS μPs, HgS NPs, and cycloheximide limited the fungal growth to 26 ± 0.94, 12.33 ± 1.6, and 28.3 ± 1.7 mm after incubation for 6 days. Besides, inhibition of Rhodotorula glutinis was of 7.6 ± 0.01 × 107 CFU/ml in control sample, but experiments included HgS μPs, HgS NPs, and cycloheximide limited the colony‐forming units of R. glutinis to 4.2 ± 0.01 × 107, 3.5 ± 0.02 × 107, and 5.9 ± 0.05 × 107 CFU/ml.
An analytical study of a source of Beauty mesons (B mesons) by the Strong decay of ϒ(11020) is performed to obtain various modes of B mesons. The non-relativistic quark model framework is used to predict the masses of the bottomonium mesons. The strong decay of the ϒ(11020) state is calculated utilizing Quark Pair Creation model. In addition, the branching ratio of the strong decay has been calculated for each decay width and using them to estimate the number of B-meson pairs for each strong decay width. The results show reasonable agreement with recent Particle Data Group data, in particular with the total strong decay width of ϒ(11020). The ϒ(11020) particle is expected to be a good candidate for the conventional ϒ(6S) state and provides both types of strange and non-strange B mesons. We found new conclusions for the strong decay widths of the ϒ(11020) in the relativistic phase space. The strong width of the B∗B∗ channel is predicted to be the highest width by the ratio (∼ 51%) concerning higher vector ϒ(11020) State. In addition, the specific Bs B∗ s channel is expected to be the highest width relative to higher ϒ resonances.
In this paper, we have studied the spectrum of bottomonium mesons behavior under the effect of three types of potentials inspired by Quantum Chromodynamics. In addition, other properties like Hyperfine splitting behavior, and Fine splitting behavior have been studied. We used these potential models within the non-relativistic quark model to present this study. We found that our expectations are consistent with experimental data and other theoretical works as well we presented new conclusions regarding the spectrum of unseen bottomonium states for S, P, and D-wave bottomonia. And we have expected other their characteristics.
A radiation source based on the inertial electrostatic confinement fusion (IECF) system is being developed for multidisciplinary research applications. The radiation outputs from the IECF system are 2.45 MeV fast neutrons and the associated co-generated X-rays with an energy less than 3 MeV. A radiation shielding study has been performed on five types of concrete to define the most efficient material for the shielding design of the system. The proposed materials were ilmenite-magnetite concrete (IMC), ordinary concrete-1 (OC-1), barite-containing concrete (BC), ordinary concrete-2 (OC-2), and serpentine-containing concrete (SC). A numerical model was applied to determine the effective removal cross-section coefficients (∑Rt) for the fast neutrons and the total mass attenuation coefficients (µm), the half-value layer (HVL), the mean free path (MFP), the effective atomic number (Zeff), and effective electron density (Neff) for photons inside the materials. The model considered the radiation source energy and the material properties of the concrete types. The results revealed that the serpentine-containing concrete exhibited the highest ∑Rt with 12 cm of concrete thickness needed to attenuate an incident neutron flux to 1/100 of its initial value. In addition, the BC shows the highest µm with a 38 cm concrete thickness needed to attenuate the 3 MeV energy X-ray flux to 1/100 of its initial value. This study suggests that a 40 cm thickness of SC or BC adequately shields the radiation generated from an IECF system with a maximum particle production rate of up to 1 × 107 n/s.