Strong Acid Research Articles

Synergizing Plasmonic Local Heating and 3D Nanostructures to Boost the Solar-to-Vapor Efficiency Beyond 100.

Solving the global challenge of freshwater scarcity is of great significance for over one billion people in the world. Solar water evaporation based on plasmonic nanostructures is one of the most promising technologies due to its high efficiency. However, the efficiency of this plasmonic nanostructure-based technology can hardly achieve 100%. Therefore, it is highly desired to develop new solar converters utilizing plasmonic local heating and reasonable structure design to break the limit of solar-to-vapor efficiency for freshwater production. Here, a plasmonic sponge is developed as a solar evaporation converter with excellent full-solar-spectrum absorption, good heat localization performance, and fast evaporation kinetics through 3D nanostructures, achieving a 131% solar-to-vapor efficiency. Distinct from the traditional 2D localized heating-based evaporation and nonmetallic 3D water evaporation, the 3D plasmonic sponge can simultaneously achieve highly efficient local heating and super large water-air interfaces for boosting solar-to-vapor efficiency. The 3D plasmonic sponge can be also used as a universal converter for purifying seawater, metal ion solutions, organic pollutant solutions, and strong acid and strong alkaline solutions. The full-solar-spectrum absorption, high efficiency, and universality in water purification suggest that the novel 3D plasmonic solar converter can bring a significant way to alleviate the crisis of freshwater resources.

Low-Temperature Borylation of C(sp3)-O Bonds of Alkyl Ethers by Gold-Metal Oxide Cooperative Catalysis.

Since ether moieties are often found not only in petrochemical products but also in natural organic molecules, the development of methods for manipulating C-O bonds of ethers is important for expanding the range of compound libraries synthesized from biomass resources, which should contribute to the goal of carbon neutrality. We report herein that gold nanoparticles supported on Lewis acidic metal oxides, namely α-Fe2O3, showed excellent catalytic activity for the reaction of dialkyl ethers and diborons, which enables the conversion of unactivated C(sp3)-O bonds to C(sp3)-B bonds at around room temperature. Various acyclic and cyclic ethers as well as a series of diborons participated in the heterogeneous gold-catalyzed borylation of unactivated C(sp3)-O bonds, to give a series of alkylboronates in high yields. Mechanistic studies corroborated that the present borylation of C(sp3)-O bonds of dialkyl ethers proceeded at the interface between gold nanoparticles and Lewis acidic metal oxides. Furthermore, adsorption IR measurements supported the notion that strong Lewis acid sites were generated at the boron atom of diborons adsorbed at the interface between Lewis acidic metal oxides and gold nanoparticles, which enabled us to ensure that the cooperation of gold nanoparticles and Lewis acidic metal oxides was responsible for the efficient transformation of unactivated C(sp3)-O bonds in ethers under mild conditions. This novel reaction technology which is specific to heterogeneous catalysts enables the activation of stable C(sp3)-O bonds of oxygenated chemical feedstock, which is beneficial for the sustainable synthesis of value-added organoboron compounds.

Enhanced sludge solid-liquid separation based on Fe2+/periodate conditioning coupled with polyoxometalates: Cell destruction and protein adsorption

Dewatering of waste activated sludge is a necessary step for achieving subsequent reduction, stabilization, and resource utilization. In this study, Fe2+/periodate (PI) coupled with polyoxometalates (POMs) conditioning was tested for realizing sludge deep dewatering. After the addition of POMs (0.20 mmol g−1 VSS), Fe2+/PI/POMs conditioning enhanced the efficiency of sludge dewatering by 42.93% compared to Fe2+/PI conditioning. It was found that the electrostatic repulsion posed a significant influence on the interaction between POMs and proteins. The reduction of electrostatic repulsion facilitated the proximity of POMs to the sludge flocs and promoted its reaction. The strong acidity and interaction with cells of POMs could induce the damage or apoptosis in sludge cells, resulting in the release of intracellular substances. The active radicals generated by Fe2+/PI process attacked TB-EPS, causing the dissolution of EPS and the decomposition of hydrophilic substances. With the assistance of Fe2+/PI process, POMs exhibited an enhanced cell-disruptive effect, thereby inducing the liberation of a greater quantity of intracellular substances. Moreover, Fe2+/PI/POMs conditioning effectively lowered the zeta potential of sludge system, facilitating the interaction between negatively charged POMs anions and the positively charged regions of proteins. This interaction tended to favor adsorption and precipitation rather than destruction. The adsorption and sedimentation of proteins by POMs further reduced the hydrophilicity of sludge system, thereby enhancing sludge dewaterability. Furthermore, POMs could enhance the electron transfer capacity of sludge system, which was beneficial for subsequent filtrate denitrification treatment.

Revealing the Overlooked Catalytic Ability of γ-Al2O3: Efficient Activation of Peroxymonosulfate for Enhanced Water Treatment.

Activated alumina (γ-Al2O3) is one of the few nanomaterials manufactured at a ton-scale and successfully implemented in large-scale water treatment. Yet its role in advanced oxidation processes (AOPs) has primarily been limited to functioning as an inert carrier due to its inherently nonredox nature. This study, for the first time, presents the highly efficient capability of γ-Al2O3 to activate peroxymonosulfate (PMS) for selectively eliminating electron-rich organic pollutants in the presence of Cl-. Through experimental and theoretical analysis, we revealed that γ-Al2O3, characterized by uniquely strong Lewis acid sites, enabled robust inner-sphere complexation between PMS and Al(III) sites, triggering the oxidation of Cl- to free chlorine through a distinctive, low-energy-barrier Eley-Rideal pathway. Such a unique pathway resulted in a 42.7-fold increase in free chlorine generation, culminating in a remarkable 145.9-fold enhancement in the degradation of carbamazepine (CBZ) compared with the case without γ-Al2O3. Furthermore, this catalyst exhibited high oxidant utilization efficiency, stable performance in real-world environmental matrices, and sustained long-term activation for over 1206 bed volumes (BV) with a CBZ removal rate exceeding 90% in fixed-bed experiments. These favorable features render γ-Al2O3 an extremely promising nanomaterial for sustainable water treatment initiatives.

Dual Role of Aerosols on Reactive Bromine Recycling in Extrapolar Marine and Continental Regions

AbstractReactive bromine species play important roles in atmospheric chemistry and influence the abundance of climate‐ and air quality‐relevant trace gases. While extensive studies have focused on bromine chemistry in polar regions, the bromine species in extrapolar regions, particularly regarding pollution‐related bromine recycling, have received less attention. In this study, we examine the factors influencing the bromine recycling at a clean marine site of the North Atlantic (Cape Verde, CVAO), a semipolluted coastal site of the South China Sea (Hok Tsui, HT), and a polluted continental site of North China (Wangdu, WD), using an observation‐based model combined with updated halogen chemistry. Our results indicate that aerosol‐related multiphase processes significantly affect bromine recycling in these extrapolar sites. Nitrate photodissociation efficiently recycled bromide into the gas phase in regions characterized by strong aerosol acidity (HT) or high aerosol concentrations (WD). Concurrently, bromine species are lost from the gas phase toward aerosol surfaces, with this process being more effective at higher liquid water content (WD > HT > CVAO). In semipolluted and polluted sites, the aerosol‐related processes resulted in elevated bromine levels in the daytime compared to nighttime, leading to larger effects of bromine species on ozone than previously thought. Our study suggests the need for a better understanding of the complex effects of aerosols on reactive halogen chemistry.

Innovative surface engineering of sustainable polymers: Toward green and high-performance materials

The development of sustainable polymers is critical to the progression of greener manufacturing processes, especially for the additive manufacturing technologies of fused deposition modeling (FDM). The study aims to explore potential application surface engineering techniques that enhance the performance of these sustainable polymers within the context of FDM. Various surface modification methods, such as plasma treatment, chemical etching, and UV irradiation, were utilized on biodegradable and recycled polymers, with the treatment process conducted under controlled conditions. Mechanical testing was done using a Tinius Olsen universal testing machine, with surface morphology analyzed through scanning electron microscopy. The outcome indicated that the tensile strength of polylactic acid improved by 15% with plasma treatment, while the thermal stability of recycled polyethylene terephthalate improved by 12% with chemical etching. Surface engineering developments on various techniques will be reviewed, particularly in optimizing them within FDM processes for different types of polymers. Different surface modifications will be compared here, analyzing aspects such as adhesion, endurance, and more overall performance. This comparison provides a fundamental outlook into the relationship between surface treatment and polymer performance, paving the way for optimization of FDM processes in sustaining material applications. These findings serve as further guidance toward making additive manufacturing much more sustainable and efficient through advanced surface engineering. The numerical improvement of material properties observed in the study will aid in further endeavors towards achieving sustainability and efficiency in additive manufacturing.

Effects of Different Weak Small Organic Acids on Clofazimine Solubility in Aqueous Media

Background/Objectives: Clofazimine (CFZ) is a Biopharmaceutics Classification System (BCS) II drug introduced in the US market in 1986 for the treatment of leprosy. However, CFZ was later withdrawn from the market due to its extremely low aqueous solubility and low absorption. In the literature, the intrinsic solubility of CFZ has been estimated to be <0.01 μg/mL, and solubilities of its different salt forms in simulated gastric and intestinal fluids are <10 µg/mL. These are extremely low solubilities for the dissolution of a drug administered orally at 100–200 mg doses. Methods: In the present investigation, seven weak organic acids (adipic, citric, glutaric, maleic, malic, succinic, and tartaric) were tested by determining the aqueous solubility of CFZ as the function of acid concentration to investigate whether any of the acids would lead to the supersolubilization of CFZ. Results: There were only minimal increases in solubilities when concentrations of acids in water were increased up to 2.4 M. The solubilities, however, increased to 0.32, 1.23, and 10.68 mg/mL, respectively, in 5 M solutions of tartaric, malic, and glutaric acids after equilibration for 24 h at 25 °C. Crystalline solids were formed after the equilibration of CFZ with all acids. Apparently, salts or cocrystals were formed with all acids, except for glutaric acid, as their melting endotherms in DSC scans were in the range of 207.6 to 248.5 °C, which were close to that of CFZ itself (224.8 °C). In contrast, the adduct formed with glutaric acid melted at the low temperature of 77 °C, and no other peak was observed at a higher temperature, indicating that the material converted to an amorphous state. Conclusions: The increase in CFZ solubility to >10 mg/mL in the presence of 5 M glutaric acid could be called supersolubilization when compared to the intrinsic solubility of the basic drug. Such an increase in CFZ solubility and the conversion of the glutarate adduct to an amorphous state are being exploited to develop rapidly dissolving dosage forms.

Propylene oligomerization over SiO2-overcoated oxides

Catalytic oligomerization of light olefins is an important CC coupling strategy that can be used to produce high-value transportation fuels and chemicals from shale gas and biomass feedstocks. In this work, vapor-phase propylene oligomerization was studied over a series of overcoated SiO2-MOx materials, whose acid site densities and strengths are tunable by the amount of SiO2 deposition and the nature of the core oxide. These materials contain acid sites only on particle external surfaces, limiting pore diffusion artifacts. SiO2-MOx materials were prepared by depositing stoichiometric amounts of tetraethyl orthosilicate (TEOS) onto Al2O3, anatase TiO2, Nb2O5, and ZrO2. Compared to the unmodified oxides, which are poor propylene oligomerization catalysts, the SiO2-MOx materials exhibit moderate activity with Al2O3, TiO2, and Nb2O5 core materials performing better than commercial amorphous silica alumina (ASA) on a surface area basis. The activity of the materials appears to be primarily driven by their Brønsted acid strength as measured by 31P TMPO MAS NMR with the rates ranked in order SiO2/Al2O3 > SiO2/TiO2 ≈ SiO2/Nb2O5 > SiO2/ZrO2. This study shows that SiO2-overcoated materials are a tunable class of materials that are active for vapor-phase propylene oligomerization.

Preparation, characterization, and ex vivo evaluation of isoxanthohumol nanosuspension

This study assessed the equilibrium solubility, oil–water distribution coefficient, and dissociation constant of Isoxanthohumol (IXN), and formulated IXN nanoparticles (IXN-Nps) using a micro media grinding method. The research characterized the particle size, polydispersity index, zeta potential, morphology, and structure of the nanoparticles, and evaluated the optimal cryoprotectant. Additionally, the study examined the toxicity and in vitro and in vivo release of IXN on HT-29 cells. IXN is classified as a Biopharmaceutical Classification System (BCS) II class drug with weak acidity. The average particle size of IXN-Nps is 249.500 nm, with a polydispersity index (PDI) of 0.149 and a zeta potential of −25.210 mV. The research identified 5 % mannitol as the optimal cryoprotectant. Compared to IXN, the half-maximal inhibitory concentration of IXN-Nps decreased to one-third, demonstrating a significant inhibitory effect on HT-29 colon cancer cells. The in vitro cumulative release rate of IXN-Nps within 24 h was 3.5 times higher than that of the IXN solution. In vivo pharmacokinetic results revealed that the oral bioavailability of IXN-Nps increased significantly by 2.8 times compared to the IXN solution. The correlation coefficient (r = 0.9227) exceeded the critical value for significance at the 0.01 (r = 0.834) level, indicating a strong correlation between in vivo and in vitro results. Consequently, the nanosuspension overcame the low solubility limitation of IXN and proved to be an effective method for enhancing the oral bioavailability of IXN

Enhanced butanol production through intracellular NADH regeneration in CdSe-C. Acetobutylicumg semi-photosynthetic biohybrid system

Current environmental challenges and energy crises highlight the urgent need for a transition in energy mix. In this study, an innovative semi-photosynthetic biohybrid system that combined light-activated cadmium selenide quantum dots (CdSe QDs) with engineered Gram-positive anaerobic bacteria, Clostridium acetobutylicumg (C. acetobutylicumg), was developed to enhance renewable butanol production. The results demonstrated that CdSe QDs could be biosynthesized intracellularly within C. acetobutylicumg through the introduction of glutathione pathway, without causing significant damage to bacteria. Furthermore, this system showed remarkable tolerance to butanol and weak acids. Under illumination, the biological synthesized CdSe QDs enabled C. acetobutylicumg to achieve a 45.5 % increase in NADH/NAD+ ratio compared to C. acetobutylicumg without CdSe QDs. When utilizing undetoxified rice straw hydrolysate in photo-fermentation, this system achieved a butanol titer of 14.82 g/L and a yield of 0.29 g/g. Overall, this work aims to effectively harness solar energy and biomass resources for sustainable clean biofuel production.

Enhanced chemical stability and H+/V4+ selectivity of microporous sulfonated polyimide via a triptycene-based crosslinker

Long durability of sulfonated polyimide in vanadium redox flow battery (VRFB) is urgently required to be solved. Herein, we synthesize a triptycene-based crosslinker and use it as chemical crosslinking point to modify a linear sulfonated polyimide for promoting its antioxidative stability. The novel triptycene-based cross-linked sulfonated polyimide (TCSPI-X) membranes featuring covalently crosslinked network display lower water uptake and swelling ratio than the commercial perfluorinated ionomer membrane (Nafion 117) membrane. More importantly, unnoticeable proton conductivity loss is appeared. We speculate this is because of the covalently crosslinking structure provides stable proton transportation channels, and the formation of micropores induced by rigid triptycene unit decrease proton migration resistance. In which, the TCSPI-5 (with 5 % molar triptycene unit) exhibit higher voltage efficiency as compared with the pristine membrane TCSPI-0. Combined with the excellent vanadium ions resistance, the TCSPI-5 reaches energy efficiency of 78 % at the current density of 140 mA cm−2. In addition, TCSPI-5 also shows high oxidation resistance even under strong acid and pentavalent vanadium ions (V5+) conditions. The above results suggest the potential of TCSPI-X membranes in VRFB application.

Fluorine-free, superhydrophobic self-healing and UV-blocking cotton fabric for oil/water separation.

The discharge of oily wastewater not only pollutes waters but also deteriorates our living environment. Superhydrophobic cotton fabric is considered as an important remedy material for oily wastewater cleanup due to outstanding advantages including low cost, high porosity and switchable wettability. However, the existing superhydrophobic fabrics cannot exhibit durable superhydrophobicity during real-life applications due to poor interaction between the coatings and fabric substrates. To address this issue, one-step strategy is proposed to fabricate superhydrophobic cotton fabric by immersion in a octa-[2-(carboxyl methyl thio) ethyl]-polyhedral oligomeric silsesquioxane/cerium dioxide/polydimethylsiloxane (POSS/CeO2/PDMS) coating. As expected, the finished cotton fabric exhibits robust superhydrophobic resistance to mechanical abrasion and chemical corrosions. Notably, the finished cotton fabric shows thermal self-healing superhydrophobicity even if undergone repetitive abrasion cycles and air plasma etching. It is proposed that the rising temperature accelerates the rotations of PDMS chains and the migrations of MAPOSS and CeO2, contributing superhydrophobic self-healing of the damaged cotton fabric. Meanwhile, the superhydrophobic fabric displays high oil/water separation efficiency even in strong acid and alkali environments. Additionally, the POSS/CeO2/PDMS coating improves mechanical, thermal and UV-blocking properties of the finished cotton fabric. This work will pave a way to exploitation and applications of novel multifunctional textiles.

Crystallization behavior of smelting slag for recovery of platinum group metals from spent automotive catalysts and preparation of foamed glass-ceramics

Spent automotive catalysts (SAC), as a significant secondary resource for platinum group metals (PGMs), can be recovered on a large scale through high-temperature smelting. Besides, as a byproduct, the glass slag lacks high-value applications. This paper proposes a recyclable method to convert slag, graphite powder (GP), and ferric oxide (Fe2O3) into foamed glass-ceramics through low-temperature sintering, significantly reducing environmental impacts and production costs. Non-isothermal differential thermal analysis was used to explore the transition and crystallization temperature range, transition kinetic, crystallization kinetic, and crystallization behavior of the glass slag. Furthermore, the influence of the foaming agent composition and heat treatment temperature on the physical properties, chemical resistance, and mechanical properties of the foamed glass-ceramics was investigated. Foamed glass-ceramics composed of 60wt% slag-30wt% Fe2O3-10wt% GP exhibited the excellent properties of a geometric density of 1.43 g/cm3, a volumetric water absorption of 26.32%, a compressive strength of 8.08 MPa, and a mass loss of 3.56% in strong acid and 0.08% in strong alkali after low temperature heat treatment at 1160°C. This study provides an insight into transforming low-value waste into high-performance foamed glass-ceramics.

Advanced PPS/MOFs composite nanofiltration membranes derived from contra-diffusion synthesis for precise molecular separation

To meet the separation requirements of polyphenylene sulfide (PPS) membranes in extremely harsh environments and to enhance the separation performance of PPS membrane material, this study utilizes Zeolitic imidazolate framework (ZIF) material with a porous structure to modify the structure of the PPS membranes. Using the Contra-diffusion synthesis method, we successfully created PPS composite membranes that were modified by ZIF-8. At the end of the three-hour reaction time, a continuous and dense layer of ZIF-8 crystals with uniform crystal size and regular crystal shape was produced on the matrix membrane's surface. The permeance to rhodamine B aqueous solution is 42.54 L m−2 h−1 bar−1, and the retention rate is 99.5 %, which has high permeability and retention performance. In the anti-pollution performance test, the composite membrane's flux recovery rate is 72.9 %, which has good anti-pollution performance. After immersion in strong acids, strong alkalis, and a variety of organic solvents, the appearance shows no evident flaws, and the separation performance in strong alkalis and five different types of organic solvents stays steady, demonstrating excellent alkali and solvent resistance. This proves that composite membranes have great potential for application in dye wastewater treatment.

Moderating acidity of ZSM-50 by Fe-substitution for n-Heptane isomerization

Effective regulation of acid sites is essential to strengthen the reaction performance and to modulate product distribution of an isomerization reaction. In this study, ZSM-50 (Al-EUO) and Fe-substituted ZSM-50 zeolites, namely FeAl-EUO-n (n = 0.25, 0.50 and 0.75) and Fe-EUO, are synthesized by a seed-assisted hydrothermal method. The study has shown that Fe has effectively entered the Al-EUO framework as a tetrahedrally-coordinated species. More importantly, the Fe-substitution has resulted in a significant increase in the amount of surface weak- and medium-strength Brönsted acids and a reduction in the strength of strong acids of FeAl-EUO-n. This study also evaluates the catalytic performance of Pt/FeAl-EUO-n catalysts in n-heptane hydroisomerization. It shows that the introduction of Fe in ZSM-50 greatly enhances the isomer yield, achieving a maximum yield of 66.1 % at 320 °C over Pt/FeAl-EUO-0.50 compared to 16.4 % at 300°C over Pt/Al-EUO. At the same time, the fraction of multi-branched iso-heptane also increases noticeably in the reaction product.

Brønsted‐Acid Catalyzed Diastereo‐ and Enantioselective Synthesis of Spiroisoindolinones from Enamides

A highly stereoselective Brønsted‐acid catalyzed synthesis of densely substituted spiroisoindolinones from enamides and 3‐hydroxy‐isoindolinones is described. With simple Brønsted‐acids, such as para‐toluene sulfonic acid, spiroisoindolinones with three contiguous stereogenic centers are formed in high yields (up to 97%) and diastereoselectivities (up to > 98:<2:0:0 dr) under mild reaction conditions. With the use of a chiral phosphoric acid catalyst, a diastereo‐ and enantioselective synthesis of the corresponding spiroisoindolinones was achieved. Mechanistic investigations indicate a step‐wise mechanism via an initial addition of the enamide to an electrophilic N‐acylimine species followed by an intramolecular aza‐Friedel‐Crafts reaction. Addition of a strong Lewis acid can be used facilitate the second step for less reactive substrates.

Efficient CeVO4/SnO2 and CeVO4/sulfated-SnO2 catalysts with high SO2 resistance for selective catalytic reduction of NOx with NH3: Influence of acid sites

Developing eco-friendly catalysts with high NOx removal efficiency and SO2 resistance in a wide temperature range is crucial. A series of efficient CeVO4/sulfated-SnO2 (CeV/Sn-S) and CeVO4/SnO2 (CeV/SnO2) catalysts were developed, and the optimal mass fraction of CeVO4 was 9 wt%. 9 %CeV/SnO2 and 9 %CeV/Sn-S achieved over 90.0 % NOx conversion at 220–385 and 240–430 °C, respectively, and they both showed notable SO2 resistance. CeV, 9 %CeV/SnO2 and 9 %CeV/Sn-S displayed different acid sites and SO2 adsorption capabilities. CeV exhibited low surface acidity, primarily Brønsted acidity. The introduction of SnO2 enhanced Lewis acidity, while sulfated SnO2 addition increased both Lewis and Brønsted acidity, and reduced SO2 adsorption, which benefited to the SO2 resistance. 9 %CeV/Sn-S had more lattice defects, a lager surface area, and higher Ce4+ and V5+ ratios than 9 %CeV/SnO2, indicating a stronger interaction between CeVO4 and sulfated SnO2. Then, 9 %CeV/Sn-S catalyst’s strong NH3 adsorption and moderate redox properties contributed to its higher NOx conversions and N2 selectivity above 330 °C, along with a broader operational window. Both Eley–Rideal (E-R) and Langmuir-Hinshelwood (L-H) mechanisms were observed in these catalysts. However, the presence of sulfates on 9 %CeV/Sn-S limited NOx adsorption, thereby reducing the contribution of L-H mechanism. The 9 %CeV/SnO2 catalyst’s strong Lewis acidity and abundant adsorbed NOx species favored the L-H mechanism, resulting in its higher NOx conversion below 250 °C compared to 9 %CeV/Sn-S. This work contributes to sharpening comprehension for the influence of acid sites and steering the design of novel SCR catalysts for efficient NOx abatement in practical applications.

One-pot synthesis of metal-containing SSZ-13 nanocrystals by interzeolite transformation of spent FCC catalysts for the methanol-to-olefins reaction

The effective recycling and recovery of spent fluid catalytic cracking catalysts (SFCCCs) are of great importance but remains challenging. Herein, we use SFCCCs as raw material to synthesize metal-containing SSZ-13 nanocrystals via interzeolite conversion for the methanol-to-olefins (MTO). The usage dose of N,N,N-trimethyl-1-adamantammonium hydroxide (TMAdaOH) for this synthesis can be controlled at remarkably low level (molar ratio of TMAdaOH:SiO2 = 0.072). Metal elements (including Ce, La, Mg, and Fe) deposited in SFCCCs are incorporated into SSZ-13 framework through isomorphous substitution of framework Si and Al. Reduced acid amount and strength resulted from the incorporation of metal elements decrease the selectivity of methane and propane, thereby increasing the selectivity of light olefins. Reduced crystal size owing to the production of aluminosilicate nanofragments caused by alkaline-induced decomposition of SFCCCs and mesopores generated by the combustion of hard-to-volatilize carbon deposits in SFCCCs reduce the molecular diffusion limitation and increase the utilization of surface acidic sites, thereby improving the anti-coking stability of SSZ-13 catalysts. Meanwhile, the incorporated metal elements in the framework reinforces the spatial confinement of the CHA cages to the transition state facilitating intermediates, thereby facilitating the accumulation of tetramethylbenzene with smaller size, which enhances the ethylene yield. The optimized SFs-0.072 exhibits superior MTO catalytic performance with about 3.8 times longer lifetime and 1.5 times higher light olefins selectivity than those of SSZ-Con without noticeable decrease of catalytic performance even after 3 successive reaction-oxidation cycles. Our present work achieves the controllable synthesis of SSZ-13 nanocrystals by using SFCCCs, which creates new opportunities for future large-scale coverting of SFCCCs into high value-added products.

A pH-responsive copper selenide nanozyme modulates multiple enzyme activities for improved healing of infected wounds

Bacterial infections can slow down wound healing and pose a threat to human health, which remains a challenging issue in clinical practice. The rise of nanozymes has provided new therapeutic approaches for antimicrobial treatment. Here, we report pH-responsive copper selenide nanoparticles (Cu1.79Se, hereafter referred to as CuSe), which exhibits peroxidase (POD)-like activity under weakly acid bacterial infection conditions, generating highly reactive hydroxyl radicals (·OH) that kill bacteria and alleviate wound infections. In the later stages of wound healing, it is neutral or weakly alkaline, the CuSe nanoparticles shows catalase (CAT) and superoxide dismutase (SOD)-like activities, clearing excessive reactive oxygen species (ROS) and producing O2, thus protecting normal tissues from damage caused by both external and endogenous ROS. The above feature helps damaged tissue cells regain their ability to proliferate and migrate, also promotes angiogenesis, achieving a "two birds with one stone" effect. It is expected that the CuSe nanoparticles could be a promising antimicrobial agent for wound healing.

Induction of Ca2+-dependent autophagy and concurrent lysosomal alkalinization underlies the cytotoxic effects of NNC-55-0396 on glioblastoma cells.

Diverse agents targeting (macro)autophagy, a critical metabolic stress response in cancer cells, have been proposed for cancer therapy. In previous studies, we showed that NNC-55-0396 (NNC) induces glioblastoma cell death by activating the Unfolded Protein Response (UPR) of ER stress and increasing cytosolic Ca2+ levels. Here, we report that NNC affects both ends of the autophagy process, causing extensive cytoplasmic vacuolation. Our results show that: (1) NNC induces autophagy downstream of UPR and Ca2+ signaling pathways, thus silencing IRE1α/JNK1 or inhibiting Ca2+/IP3R signaling prevents NNC-induced vacuolation. (2) Silencing ATG5 delays cell death, indicating that autophagy induction plays a role in NNC's cytotoxic effects. (3) NNC and other Ca2+-mobilizing agents transcriptionally upregulate p62/SQSTM1, an autophagosome cargo receptor, highlighting a role for this protein in the response to NNC. (4) Studies using tandem fluorescent-tagged LC3 and electron microscopy, however, further reveal that NNC blocks late-stage autophagy that leads to enlarged degradative compartments accumulating ubiquitin-tagged cargoes. (5) Finally, NNC impedes pro-cathepsin-B processing, an effect that is reversed with a weak acid co-treatment, suggesting that lysosomal dysfunction due to increased intraluminal pH is the underlying cause of the autophagy blockade. Together, these findings underscore a multi-level dysregulation of autophagy that contributes to NNC's anti-tumoral effects.