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[Display omitted] • An updated review of ultrasound-assisted membrane technology is provided. • Theoretical aspects of ultrasound are discussed. • Methods of ultrasound-assisted membrane fouling mitigation are reviewed. • Methods and mechanisms of ultrasound for flux enhancement are addressed. • Potential of UTDR for membrane health monitoring is discussed. In the previous decades, membrane-based separation technologies have found numerous applications in various industries. However, efficient membrane system operation necessitates cost-effective, environmentally friendly means with reduced consumption of chemicals and energy to address restrictions by polarization and membrane fouling. Ultrasound stands out as a distinct approach among current methods for manipulating the physics and chemistry of complex feed fluids in membrane filtration processes, exhibiting satisfactory performance in mass transfer and membrane cleaning. This review provides an overview of the current academic and practical insights, emphasizing physicochemical strategies for diverse ultrasound-assisted membrane systems. The objective is to summarize recent literature related to the use of ultrasound as kernel to improve the separation performance. Based on the technical perspective employing physics and chemistry principles in ultrasound for the liquid transfer, advanced ultrasound-assisted pressure-driven membrane system strategies, compatible ultrasonics applications in membrane bioreactors, and emerging ultrasound-assisted vapor pressure-driven membrane distillation are discussed. The study also covers theories and applications pertaining to acoustic cavitation, cavitation collapse, standing waves, and sonochemical radical effects. Finally, the limitations of current status are elaborated, and the deficiencies of present technologies are reflected upon for the sake of inspiration for novel ultrasound assisted membrane technologies development. [ABSTRACT FROM AUTHOR]

Highly expressed azo-reductase (AZOR) selectively reduces Azo-DON to DON in hypoxic tumor environments, impair glutamine metabolism in cancer cells, and promote tumor cell death without affecting T cell metabolism and proliferation, thereby generating strong antitumor immune responses. CB-PLG nanoparticles (CBP) mentioned in the paper can enhance the degree of hypoxia in normoxic tumors, which is conducive to efficient reduction of Azo-DON at tumor sites. [Display omitted] • Azo-DON is a novel hypoxia-active prodrug of glutamine antagonist. • Azo-DON selectively blocks tumor glutamine metabolism after reducing to DON. • T cells continue to proliferate and remain active when Azo-DON is reduced to DON. • CBP nanoparticles increase tumor hypoxia and facilitate the reduction of Azo-DON. Glutamine antagonists, such as 6-diazo-5-oxo-L-norleucine (DON), have demonstrated remarkable anti-tumor effects by blocking tumor glutamine metabolism, but their use is frequently causing toxicity. Despite the existence of multiple glutamine antagonist prodrug designs, a tumor-selective prodrug has yet to be developed. Herein, a novel prodrug of DON, Azo-DON, has been developed, which remains stable and inactive in normal tissues with sufficient oxygen levels, while can be selectively reduced to DON by highly expressed azo-reductase in hypoxic tumor environments. This leads to blockade of glutamine metabolism in cancer cells and promotes cell death without affecting T cell proliferation. In a high-hypoxic H22 hepatoma cancer model, Azo-DON showed a 1.8-fold enhancement in glutamine blockade compared to the control group, resulting in a tumor suppression rate (TSR) of 84.2% in vivo with no significant weight loss. In a low-hypoxic CT26 colon cancer model, when combined with vascular disrupting agent nanoparticles (CBP) to induce a hypoxic environment, Azo-DON exhibited a 4.6-fold enhancement in glutamine blockade over the control group, resulted in a remarkable TSR of 96.6% in vivo. This innovative approach represents a promising strategy for the application of broad-spectrum metabolic inhibitors in the field of precision cancer treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A heterogeneous catalyst was prepared by wrapping P[BVIM]CoCl 3 around the surface of Fe 3 O 4 @SiO 2. • Coupling of the catalyst with PMS as an oxidant for desulfurization. • A sulfur removal rate of over 98% at room temperature was obtained under optimal experimental conditions. • Identification of a two-step oxidation mechanism of DBT in a tandem reaction. • Obtaining some useful kinetic data for the two oxidation steps, including activation energies and reaction rates. A heterogeneous catalyst was prepared by wrapping a poly 3-butyl vinylimidazole cobalt chloride ionic liquid (P[BVIM]CoCl 3) around the surface of Fe 3 O 4 @SiO 2 magnetic nanoballs. This catalyst was coupled with the oxidant peroxymonosulfate (PMS) for extraction catalytic oxidation desulfurization (ECODS). The prepared desulfurization catalyst had superparamagnetic properties, with a saturation magnetization of 32.5 emu/g. Moreover, this caalyst was multi-porous material, ans it had a specific surface area and pore volume of 8.14 m2/g and 0.018 cc/g, respectively. The average pore diameter of catalyst was 3.9 nm. The optimal experimental conditions were as follows: the initial sulfur content of the oil was 500 ppm, the catalyst dosage was 30 mg, PMS (20 wt%) dosage was 0.6 g, the ACN dosage was 2 g, and the oil sample size was 6 g. After 20 min, a sulfur removal rate of over 98 % was achieved at 20 °C. Furthermore, the unpurified catalyst still maintained high desulfurization activity after being used for 5 times, demonstrating good stability. The desulfurization mechanism was divided into two steps: first, DBT was oxidized to DBTO by SO 4 − free radicals, and second, the DBTO was further oxidized to DBTO 2 by OH free radicals in a tandem reaction. The reaction rates for the two steps at 20 °C were 0.0144 sec−1 and 0.00115 sec−1, respectively. The activation energies associated with these steps were 65.65 kJ/mol and 105.22 kJ/mol, respectively. The quencher t-butanol had no effect on the first step but significantly inhibited the second step, meaning that DBTO became the main oxidation product. One potential application of this study is the utilization of t-butanol to regulate the oxygen content in organic sulfide oxidation products. [ABSTRACT FROM AUTHOR]

[Display omitted] • The adsorption characteristics and diffusion behavior of nanoemulsion in the tight reservoirs were systematically clarified. • Monolayer coverage of nanoemulsion stabilized by nonionic surfactants onto sandstone surfaces is more probable. • Pseudo-second order model can better describe the kinetic data. • There is a competitive relationship between the adsorption of surfactants on the oil nucleus and rock surface. Nowadays, nanoemulsions have shown a high application potential in improving hydrocarbon recovery from tight reservoirs. However, the adsorption characteristics, isotherms, kinetics of nanoemulsions onto reservoir rocks surface and the diffusion behavior into reservoir matrix are still not been systematically clarified. In this work, nanoemulsion was prepared by diluted microemulsion method using two nonionic surfactants, isopropanol, limonene and 2.0 wt% KCl solution. The static adsorption capacity measurement under different influencing factors were carried out, and the adsorption process was characterized through equilibrium isotherms and kinetic studies. Also, the diffusion behavior of nanoemulsion in the sandstone reservoir matrix were evaluated by core flooding experiments. Results indicated that the nanoemulsion was successfully synthesized and the droplet size mainly distributed between 8 and 18 nm. It had been found that the optimal static adsorption experimental parameters for 0.1 wt% nanoemulsion were 1:8 solid–liquid ratio and 50/60 mesh rock powder. Equilibrium adsorption results indicated that Langmuir model yielded a better fit which means that single-layer coverage of the surfactants composed of nanoemulsion onto the rock surfaces was more probable. Meanwhile, it was concluded that the pseudo-second order model could better describe the kinetic behavior of nanoemulsion adsorption onto the rock surfaces, which revealed that the adsorption rate was positively correlated with the nanoemulsion concentration. Dynamic adsorption experiments showed that the adsorption amount is inversely proportional to the core permeability, while the diffusion coefficient increases with the increase of permeability. Moreover, the advantage of nanoemulsions over sole surfactant is that the oil nucleus in the nanoemulsions enable control the release of the attached surfactants, and there is a competitive adsorption relationship between oil nucleus and rock surface for the free surfactants in the solution, which offers a possibility for reducing the surfactant adsorption loss and extending the invasion distance in the reservoir matrix. The findings obtained in this study can help for better understanding of the interaction mechanism between nanoemulsions and reservoir rocks, and provide guidance for selecting appropriate nanoemulsions for the enhanced oil recovery (EOR) project in tight sandstone reservoirs. [ABSTRACT FROM AUTHOR]

In the present study, the benefits of a Fenton-like treatment process in enhancing the dewaterability of drinking water treatment sludge have been investigated. It is found that using a vacuum electro-osmosis dewatering reactor often results in a low dewatering efficiency, while it can be improved significantly (by about 63% under the optimal condition) by adding the Fenton-like process in combination with acidification. The results based on the three-dimensional (3D) excitation–emission matrix fluorescence spectroscopy and Fourier-transformed infrared spectroscopy indicated that the sludge treated by the Fenton-like process could make fulvic acid-like substances disappear such that the extracellular polymeric substances (EPS) is broken and the dewaterability efficiency is improved. Furthermore, the scanning electronic microscopy analysis and particle size distribution analysis showed that the Fenton-like process and acidification destroyed the stable sludge flocs such that the water trapped in the flocs could be released easily and the dewaterability efficiency was enhanced. The 3D response surface of the water removal efficiency evidenced that the optimal operating parameters were Fe 3+ dosage of 54 mg g −1 sludge, H 2 O 2 dosage of 87 mg g −1 sludge and pH of 6.3. The results obtained in this study are expected to provide guidance and support for using the Fenton-like treatment process together with acidification to dewater drinking water treatment sludge. [ABSTRACT FROM AUTHOR]

• The porous MoP/MoO 2 heterojunction nanosheets were successfully synthesized. • Interfaces exposed active sites and porosities shortened mass transport pathway. • The catalysts exhibited enhanced HER activity in acidic and alkaline solution. • Both P and Mo sites at the interface region optimized hydrogen binding energy. Construction of nanosized pore and heterointerface provides an efficient way to enhance the electrocatalytic activity of hydrogen evolution reaction (HER). However, the exploration to tailor these structures is still insufficient for two-dimensional (2D) catalysts. Herein, a facile phosphine (PH 3) and hydrogen (H 2) vapor-assisted phase engineering strategy is proposed to successfully achieve the controllable conversion of 2D MoO 2 nanosheet precursor into 2D porous MoP/MoO 2 heterojunction nanosheets for HER. The holey lamellar properties and plentiful interfaces between 2D MoP and MoO 2 domains are intuitively confirmed by high-resolution transmission electron microscopy images. The porous MoP/MoO 2 nanosheets exhibit outstanding HER activity with low overpotentials of 90 ± 1 and 79 ± 1 mV to drive a current density of 10 mA cm−2 in acidic and alkaline electrolytes, respectively. Density functional theory calculations reveal that both P and Mo sites located on the wall of the nanopores at the interface region optimize the hydrogen binding energy, thereby accelerating the HER kinetics. [ABSTRACT FROM AUTHOR]

• The novel Fe 2 CoTi 3 O 10 -MXene composite was successfully synthesized for PMS activation. • Fe 2 CoTi 3 O 10 -MXene composite exhibited excellent catalytic performance for the 2,4-D removal. • A ternary synergistic degradation was investigated based on Fe, Co and Ti species. • The possible activation mechanism and degradation pathway of 2,4-D were proposed. In this study, a novel Fe 2 CoTi 3 O 10 -MXene (FCT-M) composite was synthesized and employed as a heterogeneous catalyst for the oxidative degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) based on peroxymonosulfate (PMS) activation. The effects of catalyst dosage, PMS dosage, pH of the initial solution, 2,4-D concentration, and the co-existing inorganic ions (HCO 3 − and Cl−) and humic acid (HA) were systematically evaluated. The catalyst with the Fe 2 CoTi 3 O 10 loading (FCT-M-2) of 6.72% demonstrated superior catalytic performance. The results showed that around 98% of 2,4-D degraded in 15 min on using 0.2 g/L FCT-M-2 composite, 0.2 g/L PMS, and 20 mg/L 2,4-D with an initial pH of 7. The co-existence of sulfate radicals (SO 4 −) and hydroxyl radicals (OH) was confirmed based upon electron paramagnetic resonance spectroscopy and radical scavenger tests, while SO 4 − was identified as the main reactive species in the FCT-M/PMS catalytic system. The superior performance of FCT-M based on PMS activation was achieved due to remarkable synergistic effect of the active sites of three transition metals (Fe, Co, and Ti) on the catalyst surface. According to the identified intermediates, a possible 2,4-D degradation pathway is proposed. Overall, this study widens the scope of employing heterogeneous catalysts towards PMS activation and sheds light on the degradation of organic pollutants in aqueous solutions. [ABSTRACT FROM AUTHOR]

[Display omitted] • The removal of C, N, P, and PFCs was enhanced by iron-carbon micro-electrolysis. • The main process and mechanism of N removal were illuminated. • The negative effect of PFCs on functional microorganisms was elucidated. The poor removal capacity of the wastewater treatment plants (WWTPs) on perfluorinated compounds (PFCs) results in the desirability of advanced treatment. Therefore, this study mainly discusses the enhanced removal mechanism of iron-carbon constructed wetlands on chemical oxygen demand (COD), phosphorus, nitrogen, perfluorooctanoic acid (PFOA), and perfluorobutanesulfonic acid (PFBS). The results showed that the removal efficiencies of most pollutants increased with the extension of hydraulic retention time (HRT) (1d, 2d, 3d). During the 3-day HRT, the average removal efficiencies in F1 (iron-carbon wetland, 100 μg/L PFCs) for COD, total phosphorus (TP), total nitrogen (TN), PFOA, and PFBS were 61.88 %, 67.92 %, 58.26 %, 78.12 %, and 80.60 %, respectively. Compared with C1 (common gravel wetland, 100 μg/L PFCs), the corresponding removal efficiencies increased by 4.68 %, 24.53 %, 10.07 %, 16.52 %, and 13.16 %, respectively. However, the removal effect of F2 (iron-carbon wetland, 200 μg/L PFCs) became worse due to the high concentration of PFCs. Further study found that the efficient removal of phosphorus in F1 was the precipitation and coagulation of Fe(III) and Fe(II). Meanwhile, the removal of nitrogen mainly relied on autotrophic and heterotrophic denitrification. Simultaneously, the combination with Feammox (the process of anaerobic ammonium oxidation coupled to iron reduction) and other pathways promoted nitrogen removal and iron cycling in F1. Further mass balance calculation of PFOA and PFBS in iron-carbon wetland found that among all matrixes (coarse sand, gravel, and iron-carbon), the contribution rate of iron-carbon to the removal PFCs was the highest. In addition, the enrichment of microorganisms related to Fe(II)-dependent autotrophic denitrification and the cultivation of iron-reducing bacteria reconfirmed the iron cycle. [ABSTRACT FROM AUTHOR]

An ordered macro-microporous single-crystalline MOF with micron-sized hollow exhibits a recorded CrO 4 2- adsorption capacity of 609 mg/g, and offers the promising application for CrO 4 2- disposal in nuclear waste. [Display omitted] • A rarely hollow single-crystalline framework 1 with ordered macro-micropores. • MOF 1 possesses the record CrO 4 2- adsorption capacity of 609 mg/g. • MOF 1 can maintain its high CrO 4 2- adsorption capacity after 400 kGy β irradiation. • 1 offers the promising practical application for CrO 4 2- disposal. The vitrification process represents an effective method for high-level radioactive waste disposal, but CrO 4 2- can form crystalline spinels within the glass to cause the secondary leak of radioactive waste. Porous materials are widely used for trapping CrO 4 2-, but the unsatisfied adsorbing capacity and poor selectivity of reported materials make CrO 4 2- enrichment to be a challenging issue. Herein, a rarely hollow single-crystalline MOF (1) with ordered macro-micropores of 13 μm and 8.6 Å was obtained, exhibiting high N 2 adsorption of 339.2 cm3/g and large BET surface area of 1150 m2/g. Cooperation effect between microporous frameworks and micron-sized channels in crystals endows 1 with excellent chromate removal capacity of 609 mg/g, which is a record value known to date among the anion-exchange materials for CrO 4 2- removal. The kinetic analysis revealed that such adsorption was a pseudo-second-order adsorption process. Framework 1 possessed high pH stability and irradiation resistance, can repeatedly absorb/desorb CrO 4 2- to some degree. More importantly, sample 1 can maintain its high CrO 4 2- adsorption capacity after 400 kGy β irradiation, offering the promising application for CrO 4 2- disposal in high-level radioactive waste. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeII/EDDS/UV/PAA was more effective than its subordinate processes in NAP degradation. • UV photoreduction and EDDS chelation assisted the FeII/FeIII cycle. • FeII/FeIII cycle in FeII/EDDS/UV/PAA process dominated the PAA activation. • A four-stage degradation model in FeII/EDDS/UV/PAA system was established. • Effects of Cl-/Br-, HCO 3 –/CO 3 2– and HA were comprehensively evaluated. The application of the integrated FeII/EDDS/UV/PAA (FEUP) process (EDDS = ethylenediamine- N,N' -disuccinic acid; PAA = peracetic acid) as a novel advanced oxidation process (AOP) for the degradation of a model contaminant, namely, naproxen (NAP), at neutral pH was investigated. The enhanced NAP degradation in this system at pH 7 was primarily attributable to the continuous activation of PAA via the UV-assisted FeII/FeIII cycle. A four-phase conceptual process of NAP degradation was established. The instantaneous degradation stage (IDS), in which FeII and PAA instantaneous react within 1 s, resulted in the degradation of ~ 20% of NAP. The rapid degradation stage (RDS), in which the regenerated FeII rapidly activates PAA to produce the hydroxyl radicals (•OH) and organic radicals including CH 3 C(O)O•, CH 3 C(O)OO•, CH 3 OO• and •CH 3 (defined as R-C•) without being scavenged by the FeII/FeIII-EDDS complexes, contributed to the degradation of ~ 55% of NAP. The slow degradation stage (SDS), during which FeII/FeIII-EDDS complexes started competing for radicals, and resulted in the degradation of ~ 15% of NAP. The continuous degradation stage (CDS), in which hydrogen peroxide (H 2 O 2) was the only oxidant because PAA was exhausted, corresponded to the degradation of another ~ 10% of NAP. The effect of water matrices including Cl-/Br-, HCO 3 –/CO 3 2–, and humic acid (HA) was evaluated: Br-, HCO 3 –/CO 3 2–, and HA exhibited an inhibiting effect on NAP degradation, while Cl- showed no influence on NAP degradation in the FEUP process. A superior degradation performance was achieved under a low FeII dosage and neutral conditions, demonstrating the great potential of the FEUP process for practical applications. [ABSTRACT FROM AUTHOR]