The unsaturated fatty acid of the cell membrane and the accumulation of intracellular glutamic acid as key determinants of freeze-drying tolerance in Bifidobacterium bifidum.

Flotation separation of fluorite from dolomite is challenging due to their similar surface properties. In this study, neutralized alkali-gelatinized soluble starch (NAGS) was used as a flotation depressant. NAGS was prepared by gelatinizing soluble starch in an alkaline solution, followed by pH neutralization. The depressive performance and mechanism of NAGS in the fluorite-dolomite flotation separation were systematically investigated. Microflotation tests showed that, at pH 7 with a sodium oleate (NaOL) concentration of 30 mg/L and NAGS concentration of 100 mg/L, the recovery difference between fluorite and dolomite in single-mineral flotation reached as high as 95.10%. In the flotation concentrate of the artificially mixed mineral, the fluorite grade was 87.09%, and the fluorite recovery was 90.12%. NAGS exhibited a pronounced selective depressive effect on dolomite, which was further confirmed by contact angle measurements. Zeta potential measurements, Adsorption capacity measurements, Fourier-transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS) were combined to elucidate the adsorption mechanism of NAGS. Collectively, NAGS adsorbs on both mineral surfaces via physisorption but with distinct dominant forces: electrostatic interactions predominate on fluorite, while hydrogen bonding is predominant on dolomite. This differential adsorption strength explains the selective depression of dolomite.

Correction to “Molecular Dynamics Insights into Surfactant-Regulated Methane Hydrate Nucleation and Growth: Comparative Roles of Sodium Oleate and Hydroxylated Sodium Oleate”

ABSTRACT The efficient flotation recovery of fine cassiterite is one of the challenges currently facing the effective utilization of resources. Previous studies have primarily focused on methods such as mineral pretreatment to enhance the flotation recovery of fine cassiterite. However, these approaches often complicate the flotation process. Thus, this study pioneers the introduction of solid microbubbles (SMB) as carriers to augment the flotation response of fine cassiterite. The microflotation experimental results indicate that, with the addition of sodium oleate (NaOL) and SMB, the flotation recovery of fine cassiterite increased from 59.99% to 68.72%, outperforming the effect of using the collector NaOL alone. Characterization analyses using Zeta potential, FTIR, and XPS revealed that SMB, due to its hydrophilic surface, does not easily adsorb directly onto the cassiterite surface. However, after the addition of NaOL, SMB is able to effectively adsorb onto the cassiterite surface. Further analysis reveals that SMB first undergoes chemisorption with NaOL, forming SMB with hydrophobic carbon chains. Subsequently, these hydrophobized SMB physically interact with the cassiterite surface, which has adsorbed NaOL, resulting in the formation of hydrophobic aggregates. This process enhances the flotation recovery of cassiterite. This study is the first to discover that NaOL serves a dual role, acting both as a hydrophobic modifier for SMB and as a collector for cassiterite. The key mechanism of interaction between the two hydrophobic aggregates and fine cassiterite through hydrophobic forces provides novel research insights and theoretical foundations for the efficient development and utilization of fine mineral resources.

Shale gas, as a clean unconventional hydrocarbon resource, faces significant challenges in safe and efficient development due to wellbore instability. Traditional drilling fluid strategies primarily rely on density control, inhibition, and plugging but are insufficient to prevent shale structural degradation caused by fluid invasion. Calcite, an important brittle mineral in shale, is highly susceptible to dissolution and structural damage. Its role in wellbore stability thus warrants an in-depth investigation. In this study, calcite in shale was selected as the research focus, and a combination of molecular simulation and experimental approaches was employed to systematically screen the interfacial interactions of representative organic functional groups with calcite to elucidate the underlying mechanisms. The results show significant differences in interfacial interaction strength among functional groups, with adsorption strength following the order: COO- > HCONHOH > HCOCH2OH > CH3NH2 > C3H6O ≈ HCHO > C2H6O, indicating that carboxyl groups have the strongest binding ability on the calcite surface. Oleate sodium (OAS), containing carboxyl groups, was then selected as a model compound for the experimental validation. Fourier-transform infrared spectroscopy, thermogravimetric analysis, and X-ray photoelectron spectroscopy analyses confirmed the successful incorporation of the OAS into shale and its chemical bonding with the calcite surface. Mechanical tests demonstrated that the OAS treatment significantly enhanced shale strength, increased the surface contact angle from 21.7 to 94.0°, and markedly increased surface hydrophobicity, effectively mitigating fluid-induced weakening. This study systematically reveals the interfacial chemical interaction mechanism between carboxyl functional groups and calcareous minerals in shale and proposes a chemical consolidation design strategy based on functional group-mineral interactions, providing new theoretical guidance for wellbore stabilization in shale formations.

Indirect effects of pH on drug solubility in fed state simulated intestinal fluids.

Fabrication of versatile and robust hydrophobic sodium oleate-modified MOF as fiber for solid phase microextraction of polycyclic aromatic hydrocarbons.

Nanobubble flotation strategy of fluorite integrating experimental and DFT analysis.

Small angle X-ray scattering reveals phase transition in sodium oleate-cysteine systems for optimized selenium nanoparticles synthesis.

The flotation separation of rare earth minerals from calcium-bearing gangue minerals, such as calcite, remains a critical technical challenge in rare earth ore beneficiation. This study focuses on a green depressant, carboxymethyl chitosan (CTS), for the flotation separation of bastnaesite, parisite, and calcite using sodium oleate (NaOL) as a collector. Through flotation tests, zeta potential measurements, Fourier transform infrared spectroscopy, wrap angle test, atomic force microscopy, and X-ray photoelectron spectroscopy, the study elucidates the selective depression and interfacial mechanism of CTS on bastnaesite, parisite, and calcite. Molecular dynamics simulations were employed to elucidate the adsorption mechanisms of CTS and NaOL at the three-phase interface. The results demonstrate that in the NaOL flotation system, when CTS functions as a depressant, the carboxyl groups (-COOH) in CTS molecules selectively chemisorb to calcium sites on the calcite surface, forming hydrophilic Ca(COOR) complexes that significantly suppress calcite floatability. In contrast, CTS exhibits only weak physical adsorption on bastnaesite surfaces, which does not interfere with NaOL collection. This differential adsorption behavior establishes CTS as an environmentally friendly green organic depressant capable of achieving the efficient separation of the three minerals.

This work aimed to optimize the micellar extraction of bioactive compounds from turmeric, using sodium oleate as surfactant. Response surface methodology was employed, considering the independent variables: mass ratio of turmeric/micellar solution (MS) of sodium oleate (MSSO), surfactant concentration and extraction time (tE). The turmeric/MSSO ratio and surfactant mainly affected the process. The optimal conditions were as follows: turmeric/MSSO = 0.01, surfactant = 1.525% and tE = 6.6 min; and the dependent variables: TPC = 181.6 ± 3.0 mg gallic acid equivalent/g turmeric dry basis (db); DPPH• = 50.6 ± 1.1 mg Trolox equivalent (TE)/g turmeric db; ABTS•+ = 142.7 ± 7.9 mg TE/g turmeric db; curcumin = 11.6 mg/g turmeric db. Micellar extraction is a sustainable, economical, and simple process compared to the conventional ethanol method. .

Selective flotation of lepidolite from quartz via aluminum-induced surface modification using sodium oleate as an anionic collector

Influence of ionic surfactant contaminants on polystyrene-air bubble interactions for microplastics removal from wastewater.

Molecular insights into the temperature-responsive interfacial properties of sodium oleate–based combined collectors for spodumene flotation

Mechanism analysis and verification of silicon separation from diamond wire saw silicon slurry by sodium oleate flotation

Strengthening the flotation separation behavior and mechanism of magnesite and dolomite in sodium oleate system with a polyphosphate environmental-friendly chelating agent

Neutrophil-derived TNF-α triggers ACSL4-mediated lipid peroxidation in post-hepatectomy liver injury.

Relevance. The protected Baikal territories are becoming more involved in the tourism industry every year, which does not contribute to the preservation of their unique natural qualities. For competent legal regulation of anthropogenic pressure and the formation of ecological culture, information is needed about the ability of the natural system to self-regulate and self-repair and the pace of this process. Aim. To compare the ecobarrier abilities of the sandy sediments of the Tagheran steppe and Olkhon Island in relation to aggressive effects. Methods. The composition of the sand samples was determined by powder diffraction on a DRON-3.0 X-ray diffractometer, and the concentrations of rock-forming oxides were determined on an S8 TIGER wave dispersion spectrometer. Sorption capacity under static and dynamic conditions of contact of sands with media simulating domestic wastewater, the surface tension or electrical conductivity of solutions was measured. The interpretation of the results of colloidal chemical studies was performed using Excel. Results and conclusions. Despite the geographical proximity of the selection sites and the granulometric similarity of the sands, their eco-barrier abilities differ significantly. The sands exhibit different activity in relation to solutions of individual surfactants, represented by anion-active sodium oleate and sodium 12/14/16-carbon organosols, as well as to synthetic detergents. In all cases, it turns out that washing the sands does not lead to complete purification. It is shown that the sorption properties of sands depend on their mineral composition, samples of Olkhon sand retain up to 70% of detergents, and Tagheran sand retains up to 50%. The island sands are rich in quartz and feldspar (97.5%) and have a high degree of pollution retention. At the same time, they are characterized by more complete purification by washing, which in natural conditions corresponds to the accumulation of pollutants in the underlying soil layers, the biota of which is under threat. The peculiarities of the mineral composition of the sands of the Tajeran steppe are manifested in less surface activity. The danger of the presence of surfactants in sand layers of this composition is associated with their ability to act as hardness reducers, contributing to the effects of disintegration. The results indicate that, under conditions of planned anthropogenic load, sand deposits can be considered as indicators of the state of the soil cover during continuous monitoring.

Lipoate-AmB-oleate-chol nanoparticles: An approach to decrease cytotoxic effects.

Fast method to synthesise Ca(OH)2 and Mg(OH)2 nanoparticles and their performance with sodium oleate coatings