Hue University Journal of Science: Natural Science

Development of heavyweight concrete incorporating steel slag as aggregate for potential application of wave-dissipating blocks in Vietnam

Sun, 24 May 2026 00:00:00 +0700

In 2024, Vietnam ranked as the 11th largest steel producer worldwide, with an annual crude steel output of approximately 22 million tonnes, generating a substantial amount of steel slag (SS). As most major steel plants in Vietnam employ Basic Oxygen Furnace (BOF) technology, BOF slag represents the dominant type of SS produced. This study proposes and evaluates the use of mixed BOF and cast SS, based on actual production proportions at the Formosa steel plant, as coarse aggregates for heavyweight concrete (SS concretes) under Vietnamese conditions. Four qualified SS types were combined and applied in concrete mixtures across three grading scenarios. The results show that SS concretes exhibit more consistent compressive strength development and more significant strain at failure than conventional concretes made with natural aggregates. The 28-day compressive strength of the SS concretes reached 113.6–117.8% of the target strength for M400 concrete. Owing to the higher density of the SS aggregates (1.23–1.42 times that of natural aggregates), the resulting concretes achieved densities 1.13–1.16 times greater than conventional mixes, with average values ranging from 2.64 to 2.73 t/m³, meeting the requirements for heavyweight concrete. These findings indicate that SS concrete has potential for applications such as wave-dissipating blocks; however, further hydraulic investigations are required to confirm this performance.

Novel MIL-53(Fe)-encapsulated gelatinous boehmite granules and their enhanced photocatalytic performance towards tetracycline

Fri, 29 May 2026 00:00:00 +0700

Developing materials with high photocatalytic activity and easy recovery remains a challenge in industry. In this work, MIL-53(Fe) crystal powder was effectively encapsulated within gelatinous boehmite to produce millimetre-scale AlOOH@MIL-53(Fe) granules using the oil-drop method. The materials were utilised for the photodegradation of tetracycline (TC). These granules underwent detailed characterisation by SEM, FT-IR, XRD, N₂ sorption, TGA, and UV-Vis DRS techniques. The resulting granular composites exhibited improved porosity and visible-light absorption. Photocatalytic testing under energy-efficient visible LED light demonstrated that the AlOOH@MIL-53(Fe) granules achieved a removal efficiency of 93% for TC, higher than that of the original MOF (82%) and the AlOOH granules without loaded MOF (54%). Kinetic analysis indicated that the photodegradation of TC followed a pseudo-second-order model, with rate constants in the following decreasing order: AlOOH@MIL-53(Fe) (0.0021 mg^–1.L.min^–1), MIL-53(Fe) (0.00074 mg^–1.L.min^–1), and AlOOH(0.00016 mg^–1.L.min^–1). Notably, the developed granules are easy to recover and retain suitable reusability in photocatalytic processes, highlighting their significant potential for real-world wastewater treatment applications.

Structural and magnetic properties of high-energy ball-milled nanoparticles CoFe₂O₄ via neutron diffraction study

Mon, 29 Jun 2026 00:00:00 +0700

In this study, we investigated the structural and magnetic properties of high-energy ball-milled CoFe₂O₄ nanoparticles using neutron powder diffraction. Rietveld refinement confirmed the structural stability of the single-phase cubic spinel (Fd-3m) during milling up to 120 min. However, the lattice parameters, including the lattice constant, bond lengths, and bond angles change with milling time. In particular, milling leads to a widening of the B–O–B bond angles and a narrowing of the A–O–B bond angles, which enhances the antiferromagnetic superexchange interaction J_AB. The refinement also reveals significant changes in the magnetic moments at the tetrahedral and octahedral sites. The variation in the average magnetic moments closely follows the evolution of the inversion degree, indicating that the reduction in magnetic moments is associated with the decrease in inversion degree during the milling process. These findings contribute to a deeper understanding of structure–property relationships in nanosized CoFe₂O₄ and provide meaningful guidance for tuning its magnetic performance through mechanical processing.

Chemical composition of Homalomena occulta essential oil and molecular docking-ADMET evaluation against antimicrobial targets

Fri, 29 May 2026 00:00:00 +0700

Homalomena occulta (H. occulta) essential oil was obtained via steam distillation, and its chemical composition was characterised using gas chromatography-mass spectrometry (GC-MS) analysis. A total of 43 compounds, predominantly oxygenated monoterpenes with linalool (40.35%), terpinen-4-ol (8.54%), and a-terpineol (3.05%) as the most abundant components, were identified. These compounds were evaluated in silico through molecular docking simulations using MOE 2022.10 software against three antimicrobial-related targets associated with pathogenic strains, namely Streptococcus pyogenes (P0C0C7), Streptococcus pneumoniae (Q8DQF8), and Candida albicans (4ESW). Several promising candidates with strong predicted inhibitory potentials were identified and ranked for each target as follows: P0C0C7: 40 (–11.2 kcal.mol^–1) > 27 (–11.0 kcal.mol^–1) > 4 (–10.9 kcal.mol^–1) » 36 (–10.9 kcal.mol^–1) > 29 (–10.4 kcal.mol^–1); Q8DQF8: 27 (–9.6 kcal.mol^–1) > 29 (–9.4 kcal.mol^–1) > 25 (–9.3 kcal.mol^–1) ≈ 41 (–9.3 kcal.mol^–1) > 36 (–9.2 kcal.mol^–1); 4ESW 42 (–11.3 kcal.mol^–1) > 38 (–10.8 kcal.mol^–1) > 21 (–10.7 kcal.mol^–1) > 32 (–10.3 kcal.mol^–1) » 41 (–10.3 kcal.mol^–1). A drug-likeness study based on Lipinski’s rule of five was generally favourable (MW < 500 Da for 43/43 compounds; logP < 5 for 41/43 compounds). The ADMET prediction results suggested good absorption and permeability, along with a low risk of major transporter- and metabolism-related issues. Overall, these findings provide a strong in silico basis, supporting further experimental antimicrobial testing for H. occulta essential oil.

Struvite precipitation for nutrient recovery from clarified shrimp pond sludge supernatant under brackish conditions

Dang Thi Thanh Loc*, Tuan Le Van, Thi Hien Luong Phan — Fri, 26 Jun 2026 00:00:00 +0700

Coastal intensive shrimp ponds generate sludge-derived supernatant containing reactive nitrogen and phosphorus that may contribute to eutrophication if discharged without appropriate treatment. This study evaluated struvite precipitation for nutrient recovery from clarified supernatant of white-leg shrimp pond sludge collected in Thuan An Ward, Hue City, Vietnam, under post-flood brackish conditions. The collected supernatant retained a relatively high native Mg²⁺ concentration (100.7 ± 9.2 mg/L), whereas NH₄⁺-N and PO₄³⁻-P were substantially diluted after flooding; therefore, NH₄⁺ and PO₄³⁻ were supplemented to restore the stoichiometric window required for crystallisation. Batch jar tests evaluated the effects of pH (8.0–9.5), Mg/N/P molar ratio (1:1:1–1.5:1:1), and reaction time (30–120 min). The optimum conditions were pH 9.0, Mg/N/P = 1:1:1, and 30 min, achieving recovery efficiencies of 61.6 ± 1.0% for NH₄⁺-N and 82.1 ± 0.3% for PO₄³⁻-P. XRD identified struvite as the predominant crystalline phase, while SEM and optical microscopy showed prismatic crystals consistent with struvite morphology. These findings demonstrate that, even under post-flood brackish conditions, clarified shrimp sludge supernatant can serve as a magnesium-rich matrix for struvite-based nutrient recovery, highlighting a promising route for resource recovery in coastal aquaculture.

Saccharomyces cerevisiae’s culture conditions for heterologous expression: A detailed investigation using reporter gene eGFP and Escherichia coli’s heat-labile toxin B subunit

Luong Nguyen*, Song NV, Lan TTP — Fri, 29 May 2026 00:00:00 +0700

The Saccharomyces cerevisiae recombinant expression host 2805 has been employed extensively for various applications, ranging from recombinant enzyme production, oral vaccine development, and viral antigen production. For all of its previous applications, recombinant yeast cells have been cultured under a conventional three-stage protocol: after being revived and grown on selective agar plates, (i) cells are seeded in 5 mL Uracil deficient medium (–Ura medium) for two days; (ii) cells are diluted at a 1:8 ratio in the complete medium YEPD and cultured for 16 hours; (iii) flask culture in YEPD for 1 to 5 days at 30 °C. Despite its routine use, the rationale and performance of this culture regime have not been systematically examined. In this study, using a synthetic, yeast codon optimised gene encoding the B subunit of Escherichia coli heat-labile toxin (LTB) fused to the reporter enhanced Green Fluorescent Protein (eGFP), we employed flow cytometry to monitor the expression dynamics in the recombinant 2805 yeast strains across all cultural stages. The results show that LTB-eGFP expression peaked on day 1 of the first seeding in the –Ura medium, dropped on day 2, then increased again after being transferred to YEPD, and then declined steadily in flask culture from day 1 to day 5. Across conditions, the percentage of fluorescent positive cells was approximately 45–60%. These results indicate that the re-optimisation of the culture protocol is necessary in order to maximise the expression efficiency.

The Using complex scaling method based on Jost function formalism to investigate single-particle resonances in ²⁴O

T. Dieu Thuy*, N. N. Bao Nguyen — Fri, 26 Jun 2026 00:00:00 +0700

We apply the complex scaling method (CSM) to study single-particle resonance states in ²⁴O by using the Jost function formalism with a Woods-Saxon plus spin-orbit potential. The CSM transformation r → rotates the branch cut of the complex momentum plane, enabling direct location of resonance poles on the physical Riemann sheet without analytic continuation. The complex-scaled Jost function is evaluated numerically, and its zeros are found with the Newton-Raphson method. A scan over five rotation angles ( rad is the scan step) confirms the q-independence of resonance pole positions, as required by the Aguilar-Balslev-Combes theorem. The physical resonance energy is q-independent for . Four single-particle resonances above the neutron threshold are identified for the and partial waves, with resonance energies of and MeV, respectively.

Development and validation of modified QuEChERS- GC/MS method for simultaneous determination of current-use pesticide residues in soil

Fri, 29 May 2026 00:00:00 +0700

Pesticide residues in soil pose potential risks to ecosystems and human health, necessitating reliable and efficient analytical methods for their determination. This study developed and validated a modified QuEChERS-based extraction procedure combined with gas chromatography-mass spectrometry (GC/MS) for the simultaneous analysis of eight commonly used pesticides in soil, including herbicides, insecticides, and fungicides. Key extraction parameters were optimised for soil matrices, focusing on solvent composition and primary-secondary amine (PSA) clean-up levels. Optimal performance was achieved with 1% acetic acid in acetonitrile and 25 mg PSA per 1 mL of extract. The method was validated according to European Commission SANTE guidelines, demonstrating good linearity (R² > 0.99), low limits of detection (3–8 µg/kg), acceptable recoveries (69–114%), and satisfactory repeatability (RSD < 13%). The validated procedure was successfully applied to agricultural soil samples from central Vietnam, where residues of pretilachlor, fluazifop-p-butyl, and trifloxystrobin were detected. The results confirm that the proposed method is reliable, cost-effective, and suitable for routine monitoring of pesticide residues in soil.

Isolation and selection of Nitrobacter spp. from shrimp ponds in Hue City

Nguyen Thi Xuan Hong*, Duc Quynh Anh Nguyen — Mon, 29 Jun 2026 00:00:00 +0700

Nitrite (NO₂^–) is a critical toxic intermediate in the nitrogen cycle and represents a major water quality concern in shrimp aquaculture. Elevated nitrite concentration can severely compromise shrimp health, productivity, and survival. This study aimed to isolate and identify Nitrobacter spp. with potential applicability in the bioremediation of nitrite-contaminated aquaculture systems. Seven Nitrobacter spp. strains were successfully isolated from sediment samples collected from shrimp ponds. The isolates exhibited consistent biochemical characteristics, among which PH11 showed a higher growth rate in vitro than the other isolates. Furthermore, this strain demonstrated efficient nitrite removal at NaCl concentrations of 0–2.5% and within a pH range of 6.5–8.0. Collectively, these findings suggest that Nitrobacter sp. PH11 is a highly promising candidate for nitrite remediation in freshwater or low-salinity aquaculture systems. Overall, a thorough understanding of nitrite toxicity and proper management of nitrogen cycling in aquatic environments are key issues to promoting the health, performance, and sustainable production of cultured species.

Antioxidant, anti-diabetic activity and chemical composition of n-hexane extract of artichoke flowers (Cynara scolymus L.)

Fri, 29 May 2026 00:00:00 +0700

This study investigated the chemical composition and antioxidant and antidiabetic activity of the n-hexane extract of artichoke flowers (Cynara scolymus L.). The GC-MS analysis of the extract identified 17 compounds belonging to different groups, including hydrocarbons, esters, alcohols and polyols, heterocyclic compounds, silicon-containing compounds, and carboxylic acids. Among these groups, carboxylic acids and esters accounted for the majority, including n-hexadecanoic acid methyl ester, oleic acid, elaidic acid, palmitic acid, linolelaidic acid methyl ester, 9-octadecenoic acid, and linoleic acid methyl ester. In vitro bioassays show that the artichoke extract exhibited significant antioxidant activity with an IC₅₀ of 43.8 ± 1.75 µg/mL by using the DPPH scavenging method and 45.2 ± 2.01 µg/mL with the ABTS method. In addition, the artichoke extract exhibited significant anti-diabetic activity with an IC₅₀ of 696.7 ± 13.63 µg/mL through the ability to inhibit α-amylase and 643.2 ± 9.45 µg/mL through the ability to inhibit α-glucosidase. These findings indicate the antioxidant and antidiabetic potential of artichoke flower extracts under in vitro conditions. Further studies are required to isolate and identify the key active constituents, elucidate their mechanisms of action, and evaluate their safety and efficacy in vivo to determine their biological relevance and potential for future applications.

Effective NiO channel engineering for performance enhancement of lateral perovskite-based UV photodetectors

Thi My Huyen Nguyen, Manh Hoang Tran, Xuan Du Dang — Fri, 29 May 2026 00:00:00 +0700

Lateral perovskite-based ultraviolet photodetectors (UV PDs) are attractive for their simple fabrication and easy integration, but their performance is often limited owing to nonuniform film formation on patterned substrates and trap-assisted recombination during lateral charge transport. In this paper, a ~70 nm sputtered NiO thin film is introduced as an interfacial channel layer prior to solution processing of halide perovskite on patterned ITO/glass with a 1 mm electrode gap. The NiO underlayer provides a crystalline wide-bandgap platform that improves perovskite film uniformity and promotes larger grains with fewer grain boundaries. Photoluminescence quenching and electrochemical impedance spectroscopy techniques further indicate reduced recombination and lower charge-transfer resistance, which is consistent with enhanced hole transport in the NiO-assisted architecture. Consequently, the NiO-integrated device exhibits a markedly increased photocurrent (0.476 to 1.28 µA at 370.92 µW/cm² under 254 nm illumination), together with improved responsivity (17.4 to 33.04 mA/W) and EQE (8.5% to 16.2%). These results demonstrate that sputtered NiO serves as an effective interfacial channel to simultaneously improve film formation and charge extraction in lateral perovskite UV photodetectors.

First-principles design of Goldene as efficient two-dimensional metal contact for Janus MoSSe-based heterostructures

Pham T. Truong, Bui D. Hoi, Chuong V. Nguyen* — Fri, 26 Jun 2026 00:00:00 +0700

Two-dimensional (2D) metal-semiconductor heterostructures play a critical role in determining contact resistance, charge injection efficiency, and overall performance of next-generation nanoelectronic devices. In this work, we computationally design a novel metal-semiconductor Goldene/Janus MoSSe heterostructure and systematically investigate its structural stability, electronic properties, interfacial charge transfer, and contact characteristics by using first-principles calculations. Our results demonstrate that the Goldene/Janus MoSSe heterostructure is energetically favourable and thermodynamically stable, with equilibrium configurations dominated by weak van der Waals interactions that preserve the intrinsic electronic properties of the constituent monolayers and facilitate experimental fabrication. Charge density difference and electrostatic potential analyses reveal pronounced interfacial charge redistribution, with electrons transferred from the Goldene layer to the MoSSe layer in both stacking configurations. As a result, a p-type Schottky contact is formed, with Schottky barrier heights of 0.57 and 0.67 eV for the Goldene/SMoSe and Goldene/SeMoS configurations, respectively. These findings highlight Goldene as a promising 2D metal electrode and provide fundamental insights for optimising contact engineering in Janus MoSSe-based nanoelectronic devices.

Electronic properties and phonon-limited carrier mobility in Janus CrBZTe₂ (Z = N, P, As) monolayers: A first-principles study

Le V. Hung, Tuan V. Vu, Andrey I. Kartamyshev, Nguyen N. Hieu* — Fri, 26 Jun 2026 00:00:00 +0700

In this work, we systematically investigate the structural, electronic, and carrier transport properties of Janus CrBZTe₂ (Z = N, P, and As) monolayers by using density functional theory. The calculations indicate that these Janus materials are dynamically and energetically stable, suggesting that they could be synthesised via conventional experimental techniques. While a CrBNTe₂ monolayer exhibits metallic behaviour, CrBPTe₂ and CrBAsTe₂ monolayers are direct band-gap semiconductors with relatively small band gaps of 0.83 and 0.72 eV, respectively, as obtained from HSE06 hybrid functional calculations. The out-of-plane structural asymmetry gives rise to a difference in the vacuum levels between the two surfaces of the proposed Janus CrBZTe₂ materials. Carrier mobility is further analysed by considering multiple scattering mechanisms to ensure reliable transport predictions. The results show that the semiconducting monolayers exhibit relatively low carrier mobility, with transport primarily limited by acoustic deformation-potential scattering. These findings provide fundamental insights into the physical properties of Janus monolayers and highlight their potential for future electronic applications.

Effects of velocity-dependent and spin-orbit terms of the Skyrme interaction on non-locality parameter of microscopic optical potentials

Fri, 26 Jun 2026 00:00:00 +0700

We investigate how the velocity-dependent (t₁ and t₂) and spin-orbit (W₀) terms of the Skyrme effective interaction influence the non-locality parameter β of the microscopic optical potential (MOP) for neutron elastic scattering off the doubly closed-shell nuclei ¹⁶O, ⁴⁰Ca, ⁴⁸Ca, and ²⁰⁸Pb at incident energies below 20 MeV. The MOP is constructed within the particle-vibration coupling framework on top of self-consistent Hartree-Fock plus random-phase approximation calculations by using the SLy5 parametrisation. Three calculation schemes are compared: the full Skyrme interaction, the interaction without t₁ and t₂, and the interaction without W₀ in the residual interaction. The velocity-dependent terms exert a pronounced and mass-dependent influence on β: removing them increases β_v by 0.27 fm for ¹⁶O but decreases it by 0.50 fm for ²⁰⁸Pb. The spin-orbit term, by contrast, produces much weaker modifications, typically below 0.1 fm. The extracted β values lie in the range 0.70–1.43 fm, with most values exceeding the widely adopted Perey-Buck value of 0.85 fm, suggesting that this empirical parameter underestimates the true microscopic non-locality for most nuclei.