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Direct conversion of syngas to aromatics (STA) over oxide-zeolite composite catalysts is promising as an alternative method for aromatics production. However, the structural effect of the oxide component in composite catalysts is still ambiguous. Herein, we investigate the size effect by selecting ZnCr2O4 spinel, as a probe oxide, mixing with H-ZSM-5 zeolite as a composite catalyst for STA reaction. The CO conversion, aromatics selectivity and space-time yield (STY) of aromatics are all significantly improved with the crystal size of ZnCr2O4 oxide decreases, which can mainly attribute to the higher oxygen vacancy concentration and thus the rapid generation of more C1 oxygenated intermediate species. Based on the understanding of the size–performance relationship, ZnCr2O4-400 with a smaller size mixing with H-ZSM-5 can achieve 32.6% CO conversion with 76% aromatics selectivity. The STY of aromatics reaches as high as 4.79 mmol gcat−1 h−1, which outperforms the previously reported some typical catalysts. This study elucidates the importance of regulating the size of oxide to design more efficient oxide-zeolite composite catalysts for conversion of syngas to value-added chemicals.

Realizing high CO conversion and high aromatics selectivity simultaneously in syngas-to-aromatics (STA) reaction is still challenging. Herein, we report a 57.5% CO conversion along with 74% aromatics selectivity over a composite catalyst consisting of Fe/ZnCr2O4 (Fe modified ZnCr2O4 spinel) oxide and H-ZSM-5 zeolite. Impregnation of only 3 wt% of Fe onto ZnCr2O4 can remarkably increase CO conversion without sacrificing the aromatics selectivity. Oxygen vacancy concentration is improved after impregnating Fe. The highly dispersed iron carbide species is formed during the reaction over Fe/ZnCr2O4 spinel oxide. The synergistic effect of oxygen vacancy and iron carbide results in a rapid formation of abundant oxygenated intermediate species, which can be continuously transformed to aromatics in H-ZSM-5. This study provides a new insight into the design of highly efficient catalyst for syngas conversion.

The traditional zeolites used in air separation are generally N2-selective adsorbents. It was found for the first time that the O2/N2 adsorption selectivity can be reversed by directly decorating the Ce metal ion sites of a traditional Y zeolite with imidazole molecules, which results in a novel O2 adsorbent. The O2/N2 selectivity changes from 0.9 to 1.6 under normal conditions, and most importantly, the O2 adsorbent is recyclable. The in situ XPS characterization results indicate that the imidazole modification can change the electronic state of Ce in the Y zeolite and increase its affinity for O2, which is confirmed by theoretical calculations. Dynamic breakthrough adsorption experiments show that the adsorbent has significant application potential in air separation.

MIL-125 is a metal-organic framework with great potential for the adsorption and separation of xylene isomers. However, MIL-125 is usually synthesized under anhydrous and anaerobic conditions. In this study, homogeneously shaped and highly crystalline MIL-125 was synthesized by introducing water-resistant titanium-containing oligomers into the synthesis process. With the assistance of the novel oligomers, MIL-125 can be synthesized in the presence of water, which meets batch-production requirements. The adsorption separation performance of the obtained highly crystalline MIL-125 was also significantly enhanced. The para-xylene/meta-xylene selectivity can reach 13.5 in mesitylene, which is higher than the selectivity values of most previously reported para-selective adsorbents. The MIL-125 xylene separation performance was verified using both batch adsorption and breakthrough experiments in the liquid phase. In addition, the influence of the solvent effect was evaluated through microcalorimetric experiments, liquid-phase adsorption experiments, and theoretical calculations.

Summary The aromatization of light alkanes (C4-C6) is an important value-added reaction. However, the yield of aromatics is always limited by the simultaneous generation of small alkanes (CH4 and C2H6) due to H/C balance. Herein, we demonstrate that the introduction of CO into light alkanes over zeolites significantly enhanced aromatic selectivity and an aromatics selectivity of 85% was achieved in the case of cyclopentane and CO coupling reaction over H-ZSM-5. Methyl-substituted cyclopentenones were observed and considered as the most important intermediates for aromatics formation. Multiple characterizations revealed the coupling mechanism: (1) CO inserts into carbenium ions to form acylium cations, (2) acylium cations react with olefins to generate unsaturated ketones, (3) unsaturated ketones cyclize to methyl-substituted cyclopentenones, (4) methyl-substituted cyclopentenones convert to monocytic aromatics. Methyl-substituted indanones were also discovered causing the generation of binuclear aromatics, such as naphthalene. Nano-sized ZSM-5 and TEOS modifications were applied to enhance the BTX selectivity.

Myocardial infarction (MI) causes disturbances in myocardial energy metabolism, ultimately leading to a poor prognosis. Cytosolic glycogen autophagy (glycophagy) and mitochondrial autophagy (mitophagy) are upregulated in MI to optimize energy metabolism but to a limited extent. Asiatic acid (AA), a pentacyclic triterpene derived from the traditional Chinese herb Centella asiatica, displays anti-inflammatory, antioxidant, and antiapoptotic activities. AA has been found to alleviate focal cerebral and liver ischemic injury by reversing mitochondrial dysfunction. In this study, we investigated whether AA exerted cardioprotective effects against MI by activating glycophagy and mitophagy to improve the energy balance. In vitro cardioprotective effects were examined in neonatal mouse cardiomyocytes subjected to oxygen-glucose deprivation for 12 h. Treatment with AA (2–50 μM) significantly increased cell viability and improved the energy metabolism evidenced by increased ATP level and phosphocreatine/ATP ratio. In vivo cardioprotective effects were studied in a mouse model of MI. Administration of AA (5–125 mg·kg(−1)·d(−1), ig) significantly reduced infarct size and ischemic myocardial injury, and improved cardiac function. AA treatment also promoted mitophagy and relieved mitochondrial edema evidenced by increased number of mitophagosomes in ischemic myocardium in vivo and increased mitochondria-light chain 3 (LC3)-II colocalization in ODG-treated cardiomyocytes in vitro. Mitophagy activation was accompanied by activation of the AMPK signaling pathway. Knockdown of AMPK abolished AA-activated mitophagy. Furthermore, we showed that glycophagy was upregulated in OGD cardiomyocytes evidenced by increased starch binding domain protein 1 (STBD1)-GABA type A receptor-associated protein-like 1(GABARAPL1) interaction and extracellular acidification rate, whereas AA treatment further promoted glycophagy accompanied by PI3K/Akt activation. PI3K inhibitor LY294002 or Akt inhibitor GSK690693 blocked the effects of AA on glycophagy and glycolysis. Finally, simultaneous inhibition of glycophagy and mitophagy abolished the cardioprotective effects and energy regulation of AA. These results demonstrate that AA protects ischemic cardiomyocytes by modulating glycophagy- and mitophagy-based energy metabolism through the PI3K/Akt and AMPK pathways.

Seed-assisted low alkalinity gel system was developed to explore the organic-free synthesis of MOR zeolite. MOR nanoassemblies with Si/Al ratio (SAR) up to 9.4 and high solid yield (84–94%) were successfully obtained under controlled low alkalinity conditions. Characterization results demonstrate that the acid strength increases in parallel with the SAR, while the total acid amount and the proton distribution in the main channels and the side pockets are similar for the samples. The proton distribution in the H-MOR is not straightforwardly related to the Na+ distribution in the as-synthesized MOR, implying the transfer of the protons among the oxygen sites of framework T atom. Relative to low-silica samples I-5.3 and I-7.4, sample I-9.4 displays the best mass transfer performance and accessibility of the acid sites by pyridine due to its relatively low Al density and mild dealumination degree. Correspondingly, sample I-9.4 (pyridine-modified catalyst) shows the best activity with ca. 100% selectivity of methyl acetate (MAc) in the DME carbonylation reaction. The high steady MAc yield (6.8 mmol/g/h) over sample I-9.4 suggests the promising application of MOR nanoassemblies synthesized by this economical organic-free strategy

Summary The first C–C bond formation mechanism in the methanol-to-hydrocarbons (MTH) process has always been a highly controversial issue. Using solid-state NMR spectroscopy, the initial C1 reactants and C1 intermediates were observed on the HSSZ-13 zeolite surface. In particular, for the first time, the highly reactive ethene precursor, surface ethoxy species, was directly captured under a real MTH reaction. These findings and in situ captured activated C1 reactants linked C1 species and initially generated ethene, in which C1 intermediates activate methanol/DME to form the first C–C bond. For such a difficult-to-detect and extremely initial reaction process, the advanced ab initio molecular dynamics technology simulated the complete process from C1 reactants to product. The visualized reaction process vividly shows methanol/DME in the gas phase approaching SMS/TMO on zeolite, being activated via effective collision and methylation to generate an ethene precursor. The zeolite catalyst and active C1 intermediates contribute together to the first C–C bond formation in a synergistic manner.

Summary Achieving high conversion of syngas to fuels and basic chemicals with excellent selectivity and stability remains a challenge. Here, we report an 80.6% selectivity of gasoline-range C5–11 hydrocarbons at 86.3% CO conversion over a dual-bed catalyst (CZA + Al2O3)/N-ZSM-5(97) that consists of an upper-bed syngas-to-dimethyl ether (DME) catalyst (CZA + Al2O3) and a lower-bed DME-to-gasoline catalyst (nano-sized N-ZSM-5(97) zeolite). This dual-bed catalyst exhibits an excellent stability in a 110-h reaction test. The iso/n-paraffin ratio in the C5–11 is up to 18. For the lower-bed zeolite catalyst, the nano-sized structure is beneficial to reduce coke and prolong lifetime; meanwhile, the low acid content is advantageous to increase C5–11 selectivity. The 2,3-dihydro-1H-inden-1-one species can be definitely detected and identified in the spent lower-bed micro-sized M-ZSM-5(18) catalyst. They are regarded as intermediates to generate polycyclic aromatics, which generally lead to catalyst deactivation. The dual-bed catalyst (CZA + Al2O3)/N-ZSM-5(97) suggests a promising application in producing gasoline from syngas.

Methanol-to-olefins (MTO) is industrially applied to produce ethylene and propylene using methanol converted from coal, synthetic gas, and biomass. SAPO-34 zeolites, as the most efficient catalyst in MTO process, are subject to the rapid deactivation due to coke deposition. Recent work shows that steam regeneration can provide advantages such as low carbon dioxide emission and enhanced light olefins yield in MTO process, compared to that by air regeneration. A kinetic study on the steam regeneration of spent SAPO-34 catalyst has been carried out in this work. In doing so, we first investigated the effect of temperature on the regeneration performance by monitoring the crystal structure, acidity, residual coke properties and other structural parameters. The results show that with the increase of regeneration temperature, the compositions of residual coke on the catalyst change from pyrene and phenanthrene to naphthalene, which are normally considered as active hydrocarbon pool species in MTO reaction. However, when the regeneration temperature is too high, nitrogen oxides can be found in the residual coke. Meanwhile, as the regeneration temperature increases, the quantity of residual coke reduces and the acidity, BET surface area and pore structure of the regenerated samples can be better recovered, resulting in prolonging catalyst lifetime. We have further derived the kinetics of steam regeneration, and obtained an activation energy of about 177.8 kJ·mol−1. Compared that with air regeneration, the activation energy of steam regeneration is higher, indicating that the steam regeneration process is more difficult to occur.

EAB zeolite was successfully prepared and applied to selective adsorption of Li+, Na+ and K+ ions. The physical and chemical properties of the adsorbent were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscope (SEM) and thermogravimetry (TG) methods. The ion exchange behaviours for Li+, Na+ and K+ ions in monomcomponent and multicomponent solutions were studied. In independent ion exchange, the ion exchange capacities ratios α(Na/Li) and α(K/Li) were 3.8 and 6.2, respectively. In competitive ion exchange, the selectivities β(Na/Li) and β(K/Li) increased with the initial concentrations and reached 409 and 992 when the initial concentrations was 100 mmol/L. The thermodynamic study results showed that Gibbs free energy change (ΔGΘ) of ion exchange reaction between Li-EAB and K+ was −34.96 kJ/mol, indicating that ion exchange of K+ ions was more energetically favourable than Li+ ions. The calculation results showed that the energy barriers of ion exchange increased in the order K+

In this study, the separation performance of propylene and propane on SAPO-17 molecular sieve was investigated by static and dynamic adsorption. The adsorbent possessed good regeneration behavior because the strong adsorption of propylene at room temperature was eliminated by ion exchange treatment. Dynamic adsorption experiments revealed that the kinetic separation selectivity of propylene and propane was as high as 1980, which could be attributed to the energy barrier difference when diffusing through the eight-membered ring of SAPO-17 molecular sieve. The breakthrough experiments verified the good separation performance of the SAPO-17 adsorbent, which suggests that it has considerable application potential in propylene/propane separation.

Syngas to aromatics (STA) over bifunctional catalysts has attracted much attention in recent years, but the mechanism underlying the formation of aromatics remains controversial. The critical reaction intermediates, carboxylates, were first identified and then confirmed to essentially promote aromatization in the syngas conversion over a ZnCrAlOx&H-ZSM-5 composite catalyst. This study provides evidence that the carboxylates can be formed during the reactions of formate species and olefins. In addition, it is shown that the carboxylates favor the formation of aromatics over H-ZSM-5 even in the presence of H2. A novel mechanism for the formation of aromatics via the generation and transformation of carboxylate intermediates is proposed, and the transformation of carboxylates to aromatics via methyl-2-cyclopenten-1-one (MCPO) intermediates is indeed likely. A better understanding of the formation mechanism of aromatics would help optimize the composite catalyst.

NGF PLGA nanoparticles can exert a protective effect on hUCMSCs and promote the paracrine effects of hUCMSCs on angiogenesis and cardiomyocyte protection through TrkA-PI3K/Akt signaling pathway, the same with free NGF. The application of NGF PLGA nanoparticles in the hUCMSC fibrin cardiac patches can significantly improve the retention of transplanted hUCMSCs and enhance their ability to reduce myocardial apoptosis and promote angiogenesis in the mouse heart after MI.

Recent advances in the shape selectivity of zeolites and molecular sieve catalysts for the methanol-to-olefins (MTO) reaction are elaborated in this minireview. The concept and classification of shape selectivity are briefly introduced and summarized. The effect of cavity structure of cavity-type zeolites and molecular sieves are comprehensively discussed, with focus on the formation of hydrocarbon pool intermediates, reaction route, diffusion, product selectivity, as well as deactivation in the chemical environment of cavity-type molecular sieves. Furthermore, the impact of topology of zeolites and molecular sieves on reaction route and product selectivity are elucidated, with special attention on the shape selectivity of 1-dimensional 10-membered ring zeolites. The debate regarding the impact of coke formation on product selectivity over SAPO-34 is also discussed in detail. Moreover, the progress of modification strategies including metal cations incorporation and pre-coking process for improving shape selectivity have been summarized. The perspective of shape selective catalysis in future is outlined and predicted.

Acetone is currently produced by large amount of propylene and benzene, and its synthesis from a cheap and non-petroleum material has not yet been reported. Here, we present a new method for acetone production, which involves the carbonylation of dimethyl ether (DME) to methyl acetate and its subsequent ketonization to acetone over pyridine-modified H-mordenite. This convenient approach offers an acetone selectivity of 73% (CO2 excluded) and a DME conversion of 100% at 553 K. Spectral and isotopic studies revealed that the ketonization of methyl acetate was promoted by carbonylation, while the formation of a ketene intermediate was demonstrated by the formation of CH2DCOOD and two types of pyrones. A ketene-based ketonization mechanism was also proposed based on the kinetic isotope effect of CH2=13C O, indicating that the acetyl moiety contributed to the acyl part of acetone, while the ketene moiety was responsible for the alkyl part of acetone and the generation of CO2.

The selective synthesis of nanomaterials with different morphologies and crystal facets is of great significance for catalytic properties and practical applications. We report a strategy for controllable fabrication of hierarchical Co3O4 materials with various morphologies (ellipsoidal, flowerlike, book-shaped, spindlelike) and study their catalytic properties in propane oxidation. Co3O4-B (book-shaped) is found to exhibit the highest propane oxidation rate (0.86 × 10-8 mol m−2 s−1) and the highest turnover frequency (TOF = 11.49 × 10−3 s−1) at 220 °C. This confirms that Co3O4-B provides a higher specific surface area, a highly exposed {1 1 0} facet, and abundant Co3+ cations, which make it exhibit favorable low-temperature reducibility and oxygen mobility and thus improve its catalytic activity. In situ diffuse reflectance infrared Fourier transform spectroscopic analysis reveals that the intermediates, such as carboxylate and carbonate species, are involved in propane oxidation. Furthermore, Co3O4-B shows high water-resistance performance, and no significant deactivation is observed after long-term stability and reusability tests.

The adsorption and diffusion of adsorbates or reactants are the most essential steps in zeolite-based processes for gas separation and catalysis. An explicit description of the relationship between...

Decarbonylation of carboxylic acids is an effective reaction for alkene production but suffers from the requirement of homogeneous transitional-metal-based catalyst, ligand, and stoichiometric addi...

Metal-modified H-ZSM-5 has a high selectivity of aromatics in methanol to aromatics (MTA) reaction, which is often attributed to the metal promoting the aromatization of intermediate olefins. However, the effect of methanol dehydrogenation on aromatics formation over these catalysts is rarely studied. Here, we report that HCHO, which is formed by methanol dehydrogenation over Zn/H-ZSM-5 prepared by Zn impregnation, can participate in the synthesis of aromatics. Methanol conversion can produce more aromatics than olefins (propylene or ethylene) conversion over Zn/H-ZSM-5, indicating the conventional MTA pathway including methanol-to-olefins and olefins-to-aromatics is not complete. Moreover, an MTA mechanism including the conventional pathway and the methanol and HCHO coupling pathway is systematically proposed.

Direct converting carbon dioxide into hydrocarbon fuels and value-added chemicals would offer a very attractive approach for efficient utilization of CO2 as a carbon resource. Although, olefins, aromatics and gasoline have been successfully synthesized by CO2 hydrogenation, highly selective conversion of CO2 and H2 into C2+ hydrocarbon is still challenging due to a high C–C coupling barrier and inhibiting the production of other long-chain hydrocarbons. Here, we report a composite catalyst made of InZrOx and SSZ-13 molecular sieve (InZrOx + SSZ-13), which exhibits 74.5% propane selectivity at 623 K. The 8-MR micropores and the higher strength of the acid for SSZ-13 benefit the formation of propane. Compared with pure InOx and m-ZrO2, the composite oxide InZrOx containing more oxygen vacancies, exhibits to be more readily reduced by H2 and easier to adsorb and desorb CO2 within the reaction temperature. All those could be beneficial to the activation and conversion of H2 and CO2. The catalytic performance of InZrOx + SSZ-13 in CO2 hydrogenation provides a potential for production of propane.

Direct observation of the activation and transformation of reactant molecules is extremely attractive but very challenging in the study of most chemical processes. Here is reported the first case of dynamic activation of C1 molecules in zeolite-catalyzed chemistry. During the methanol conversion over the HZSM-5 zeolite, a sequence of progressive activation states of dimethyl ether (DME) evoked by the special catalysis from CH3-Zeo, a hybrid supramolecular catalytic system formed by the organic methylic species growing on the inorganic silico-aluminate zeolite framework, has been directly observed by in situ ssNMR spectroscopy at programmed temperatures. Operando simulations visually display the variability of this hybrid supramolecular system of which the C–O bond property goes through a dynamic transition from covalent to ionic with the temperature increase, and thus the gradually enhanced electrophilicity of CH3δ+ and nucleophilicity of Zeoδ− lead to the dynamic activation of DME. This dynamic transition is generally reflected in the alkyl-Zeo system with other alkoxy groups, which linked the alkoxy species and carbocations in zeolite catalysis. Consequently, this work not only sheds light on the key issue of the first carbon–carbon (C–C) bond formation in the methanol to hydrocarbons (MTH) process but also brings a new awareness on the essence of acid catalysis in zeolite mediated chemical processes., In zeolite-catalyzed chemistry, dynamic activation of C1 molecules by CH3-Zeo catalysis has been first revealed by the combination of in situ ssNMR spectroscopy and AIMD simulation.

Methanol-to-olefins (MTO), the most important catalytic process producing ethylene and propylene from non-oil feedstocks (coal, natural gas, biomass, CO2, etc.), is hindered by rapid catalyst deactivation due to coke deposition. Common practice to recover catalyst activity, i.e. removing coke via air combustion or steam gasification, unavoidably eliminates the active hydrocarbon pool species (HCPs) favoring light olefins formation. Density functional theory calculations and structured illumination microscopy reveal that naphthalenic cations, active HCPs enhancing ethylene production, are highly stable within SAPO-34 zeolites at high temperature. Here, we demonstrate a strategy of directly transforming coke to naphthalenic species in SAPO-34 zeolites via steam cracking. Fluidized bed reactor-regenerator pilot experiments show that an unexpectedly high light olefins selectivity of 85% is achieved in MTO reaction with 88% valuable CO and H2 and negligible CO2 as byproducts from regeneration under industrial-alike continuous operations. This strategy significantly boosts the economics and sustainability of MTO process., Methanol-to-olefins is hindered by rapid catalyst deactivation due to coke deposition. Here the authors demonstrate an approach of directly transforming coke to active intermediates to simultaneously recover catalyst activity and boost light olefins selectivity.

Two isostructural Ni(II)/Co(II)-based metal-organic frameworks (MOFs), namely {[M3(L)2(bpb)3(H2O)4]·2DMF·2H2O}n [M = Ni (HL-5, HL is short for Hui-Ling Liu); M = Co (HL-6); H3L = 2′,6′-dimethyl-[1,1′-biphenyl]-3,4′,5-tricarboxylic acid; bpb = 1,4-bis(pyrid-4-yl)benzene], have been hydrothermally synthesized and structurally characterized. Both HL-5 and HL-6, which have the same three-interpenetrated 3D pillared-layer framework with sqc306 type topology, present good selective methyl orange (MO) adsorption over rhodamine B (RhB). Moreover, the catalytic CO2 cycloaddition properties with epoxides of the two MOFs have also been studied at ambient pressure and temperature.

Studies of nanomedicine have achieved dramatic progress in recent decades. However, the main challenges that traditional nanomedicine has to overcome include low accumulation at target sites and rapid clearance from the blood circulation. An interesting approach using cell membrane coating technology has emerged as a possible way to overcome these limitations, owing to the enhanced targeted delivery and reduced immunogenicity of cell membrane moieties. Mesenchymal stem cell (MSC) therapy has been investigated for treating various diseases, ranging from inflammatory diseases to tissue damage. Recent studies with engineered modified MSCs or MSC membranes have focused on enhancing cell therapeutic efficacy. Therefore, bioengineering strategies that couple synthetic nanoparticles with MSC membranes have recently received much attention due to their homing ability and tumor tropism. Given the various membrane receptors on their surfaces, MSC membrane-coated nanoparticles are an effective method with selective targeting properties, allowing entry into specific cells. Here, we review recent progress on the use of MSC membrane-coated nanoparticles for biomedical applications, particularly in the two main antitumor and anti-inflammatory fields. The combination of a bioengineered cell membrane and synthesized nanoparticles presents a wide range of possibilities for the further development of targeted drug delivery, showing the potential to enhance the therapeutic efficacy for treating various diseases.

Na+-free Cu-SSZ-13 zeolites have been rationally synthesized via a cooperative strategy, which has the advantages of rapid crystallization (9-48 h), high yield (86-94%) and adjustable Cu content. The NH3-SCR catalytic performance and hydrothermal stability of the calcined materials were studied and correlated with their physicochemical properties.

To alleviate diffusion-limited photoinduced electron transfer (PET) in solution, a triphenylamine-derived dye and a Keggin polyoxometalate-type electron relay were coupled into a coordination polymer to photoinduce long-lived charge-separation pairs with enough reductive/oxidative potential to pump multiple electrons unidirectionally from external electron donors to acceptors, thus furnishing photocatalytic radical couplings to afford value-added α-amino C-H arylation products.

Efficient direct transformation of methane into value-added chemicals has great significance for long-term sustainability of fuels and chemicals, but remains a major challenge due to its high inertness. Reported here is that methane can be activated effectively via carbonylation with CO over Zn/HZSM-5 catalysts under mild conditions. The selectivity to aromatics alone reaches 80% among all hydrocarbon products at 823 K, whereas as high as 92% ethane selectivity is achieved at a lower temperature of 673 K. 13CO isotope labelling experiments demonstrate that approximately 50% of the carbon atoms in all the products originate from carbon monoxide, whereas another half of the carbons come from methane, indicating that the precursors of hydrocarbon products are acyl compounds and/or acetic acid formed by carbonylation of methane with carbon monoxide. This provides potential for transformation of methane into value-added chemicals under mild reaction conditions.

Nanoparticle-mediated photothermal therapy (PTT) has shown promising capability for tumor therapy through the high local temperature at the tumor site generated by a photothermal agent (PTA) under visible or near-infrared (NIR) irradiation. Improving the accumulation of PTA at the tumor site is crucial to achieving effective photothermal treatment. Here, we developed temperature-activatable engineered neutrophils (Ne) by combining indocyanine green (ICG)-loaded magnetic silica NIR-sensitive nanoparticles (NSNP), which provide the potential for dual-targeted photothermal therapy. The combined effect of neutrophil targeting and magnetic targeting increased the accumulation of PTA at the tumor site. According to magnetic resonance imaging (MRI), the retention of intravenous injected NSNP-incorporated neutrophils within the tumor site was markedly augmented as compared to free NSNP. Furthermore, when irradiated by NIR, NSNP could cause a high local temperature at the tumor site and the thermal stimulation of neutrophils. The heat can kill tumor cells directly, and also lead to the death of neutrophils, upon which active substances with tumor-killing efficacy will be released to kill residual tumor cells and thus reduce tumor recurrence. Thereby, our therapy achieved the elimination of malignancy in the mouse model of the pancreatic tumor without recurrence. Given that all materials used in this system have been approved for use in humans, the transition of this treatment method to clinical application is plausible.

The synthesis of TS-1 zeolites is regarded as a milestone in zeolite history, and it has led to the revolution of the green oxidation system of using H2O2 as an oxidant, leaving only water as the byproduct. However, because of the highly hydrolyzable titanium source, the preparation of TS-1 requires complex synthesis conditions. Moreover, the difference in the hydrolysis rate between the silicon source and titanium source tends to increase the difficulty of titanium insertion into the framework, and it is easy to generate extra-framework Ti species during the synthesis. Here, a high-quality TS-1 zeolite with a large external surface area and free of extra-framework Ti species has been successfully synthesized by using a kind of novel polymer containing titanium and silicon. Due to the high hydrolysis resistance of the polymer reagent, a good matching of the hydrolysis rate between the silicon source and the titanium source is realized during crystallization, which facilitates the incorporation of titanium into the framework. Furthermore, the TS-1 zeolite exhibited excellent catalytic performance in n-hexane oxidation with hydrogen peroxide as the oxidant. This method of synthesizing zeolites from polymers is expected to be widely applied for the synthesis of other titanium-containing zeotype materials.

Purpose Lung adenocarcinoma is one of the common causes of cancer-related deaths worldwide. AHNAKs are giant proteins, which are correlated with cell structure and migration, cardiac calcium channel signaling, and other processes. Current studies identified AHNAK2 as a novel oncogene in some cancers; however, studies on its function in lung cancers are limited. Materials and Methods The expression of AHNAK2 was analyzed in normal lung tissues, lung adenocarcinoma tissues, and paracancerous tissues using the Oncomine database. It was further verified in relative cell lines by real-time quantitative polymerase chain reaction and Western blotting (WB). Adenocarcinoma cell lines were transfected with si-NC and si-AHNAK2 by lipofectamine 3000 and treated with or without TGF-β1, and cell migration and invasion were detected by wound-healing and transwell assays. The expression of epithelial-mesenchymal transition (EMT) markers was detected by WB, as well as that of phosphorylated-Smad3 (p-Smad3) and Smad3 levels. After Smad3 phosphorylation inhibitor was added to the adenocarcinoma cell lines, migration and invasion were detected by wound-healing and transwell assays, and the expression of EMT markers was detected by WB when the cells were transfected with si-NC and si-AHNAK2 and treated with or without TGF-β1. Results We found higher expression of AHNAK2 in lung adenocarcinoma tissues through the Oncomine database and further verified its high expression in relative cell lines. When the cells were stimulated with TGF-β1, knockdown of AHNAK2 suppressed cell migration, invasion, and EMT, and inhibited TGF-β–induced Smad3 signaling. When p-Smad3 was inhibited, knockdown of AHNAK2 had no effect on the two cell lines investigated when treated with or without TGF-β1. Conclusion AHNAK2 acts as an oncogenic protein and promotes migration, invasion, and EMT in lung adenocarcinoma cells via the TGF-β/Smad3 pathway. Thus, it may be a novel target for lung adenocarcinoma therapy.

Adult hearts are hard to recover after cardiac injury due to the limited proliferative ability of cardiomyocytes. Emerging evidence indicates the induction of cell cycle reentry of cardiomyocytes by special treatment or stimulation, which offers adult heart regenerative potential. Herein, a microRNA (miRNA) screening in cardiomyocytes identified miR-301a enriched specially in the neonatal cardiomyocytes from rats and mice. Overexpression of miR-301a in primary neonatal cardiomyocytes and H9C2 cells induced G1/S transition of the cell cycle, promoted cellular proliferation, and protected cardiomyocytes against hypoxia-induced apoptosis. Adeno-associated virus (AAV)9-mediated cardiac delivery of miR-301a to the mice model with myocardial infarction (MI) dramatically promoted cardiac repair post-MI in vivo. Phosphatase and tensin homolog (PTEN)/phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway was confirmed to mediate miR-301a-induced cell proliferation in cardiomyocytes. Loss of function of PTEN mimicked the miR-301a-induced phenotype, while gain of function of PTEN attenuated the miR-301a-induced cell proliferation in cardiomyocytes. Application of RG7440, a small molecule inhibitor of AKT, blocked the function of miR-301a in cardiomyocytes. The current study revealed a miRNA signaling in inducing the cell cycle reentry of cardiomyocytes in the injured heart, and it demonstrated the miR-301a/PTEN/AKT signaling as a potential therapeutic target to reconstitute lost cardiomyocytes in mammals., Graphical Abstract, Yu and colleagues identified a gene, miR-301a, that can induce cellular proliferation and protect cells against hypoxia-induced apoptosis in cardiomyocytes. Targeted cardiac delivery of miR-301a promoted cardiac repair in the injured heart. This work demonstrated miR-301a/PTEN/AKT signaling as a potential therapeutic target to reconstitute lost cardiomyocytes in mammals.

A high performance HZSM-5 catalyst for liquid phase dehydration of methanol to dimethyl ether (DME) was developed by optimizing Si/Al ratio and hydrothermal treatment temperature. During 6788 h long term test, DME selectivity kept above 99.96% and only slight deactivation was observed primarily due to coking and decline of HZSM-5 crystallinity.

The high-temperature (HT) and low-temperature (LT) hydrothermal stabilities of molecular-sieve-based catalysts are important for the selective catalytic reduction of NOx with ammonia (NH3-SCR). In this paper, we report a catalyst, Cu2+ loading SAPO-17, synthesized using cyclohexylamine (CHA), which is commercially available and inexpensive and is utilized in NH3-SCR reduction for the first time. After systematic investigations on the optimization of Si and Cu2+ contents, it was concluded that Cu-SAPO-17-8.0%-0.22 displays favorable catalytic performance, even after being heated at 353 K for 24 h and at 973 K for 16 h. Moreover, the locations of CHAs, host–guest interaction and the Bronsted acid sites were explored by Rietveld refinement against powder X-ray diffraction data of as-made SAPO-17-8.0%. The refinement results showed that two CHAs exist within one eri cage and that the protonated CHA forms a hydrogen bond with O4, which indicates that the proton bonding with O4 will form the Bronsted acid site after the calcination.

SAPO-34s with varying Si content templated by bulky tetraethylammonium hydroxide (TEAOH) were prepared to investigate the effect of Si environments on the selective catalytic reduction (SCR) of NOx and the moisture stability of Cu-SAPO-34 catalysts. These Cu-SAPO-34s have similar Cu loadings, isolated Cu2+ content, and Bronsted acid sites (BAS). Both the ratio of Si islands and the acid strength of Cu-SAPO-34s increase with increasing Si content. In situ diffused reflection infrared Fourier transform spectroscopy (DRIFTS) studies reveal that the NH3 adsorbed on mild BAS (associated with Si(4Al) species) is more active for NOx conversion than NH3 adsorbed on strong ones (associated with Si islands). This agrees well with the high turnover frequency (TOF) and the low activation energy on Cu-SAPO-34 with low Si content and abundant Si(4Al) species (sample Si-7.7). Upon hydration treatment, the textural properties, strong acid sites, and reducibility of isolated Cu2+ ions show a decrease. This deterioration intensifies with the increasing Si islands in the catalysts due to the easier occurrence of Si migration and the formation of larger Si islands. Sample Si-7.7 exhibits the best moisture stability and thus well-preserved denitration performance. These results imply that a practical Cu-SAPO-34 catalyst with superior activity and moisture stability may be achieved by controlling the Si environments of SAPO-34 templated by bulky amines.

We investigated the effect of a cyclic chain structure on the wear resistance of polymer brushes via coarse-grained molecular dynamics simulations. Friction simulations were performed for cyclic an...

Methanol-to-olefins(MTO) reaction is one of the important non-petroleum routes to produce light olefins over acidic molecular sieves. In this study, the complete reaction course of MTO on SAPO-34 molecular sieve with retained organics evolution from induction period to deactivation period was investigated systematically at different weight hourly space velocities(WHSV) of methanol. By the aid of 12C/13C-methanol isotopic switch experiment, the dual cycle mechanism involving aromatics-based cycle and alkenes-based cycle was evaluated during the whole reaction process. The detailed reaction route varied with the evolution of the retained organics in the catalyst at different reaction stages. The aromatics-based cycle and alkenes-based cycle alternately dominate the reaction process. In the efficient reaction period, aromatics-based cycle is the main reaction mechanism, while in the induction and deactivation periods, the contribution of alkenes-based cycle mechanism will become more important.

Water is the most important substance in nature. Imitating the formation of natural materials, molecular sieves have been synthesized under hydrothermal conditions and applied in industry. Herein, we reveal an unforeseen observation on a very special water-induced structural dynamic process of these materials. Dynamic and reversible breaking and forming of T-O-T bonds in silicoaluminophosphate (SAPO) occurs through interactions between gaseous water and the molecular-sieve framework under mild hydrothermal conditions and is confirmed by detection of the incorporation of 17 O from H2 17 O into molecular-sieve framework. Encapsulation of the bulky molecules trimethylphosphine and pyridine (kinetic diameters much larger than the pore size of SAPO-34) into CHA cavities consolidated the water-induced dynamic process. Consequently, new insights into the dynamic features of molecular sieves in water are provided. The ship-in-a-bottle strategy based on these findings also open new fields for fine acidity identification and gives extra boost in shape-selective catalysis.

Heterogeneous catalysts with ultra-small clusters and atomically dispersed (USCAD) active sites have gained increasing attention in recent years. However, developing USCAD catalysts with high-density metal sites anchored in porous nanomaterials is still challenging. Here, through the template-free S-assisted pyrolysis of low-cost Fe-salts with melamine (MA), porous alveolate Fe/g-C3N4 catalysts with high-density (Fe loading up to 17.7 wt%) and increased USCAD Fe sites were synthesized. The presence of a certain amount of S species in the Fe-salts/MA system plays an important role in the formation of USCAD S-Fe-salt/CN catalysts; the S species act as a “sacrificial carrier” to increase the dispersion of Fe species through Fe-S coordination and generate porous alveolate structure by escaping in the form of SO2 during pyrolysis. The S-Fe-salt/CN catalysts exhibit greatly promoted activity and reusability for degrading various organic pollutants in advanced oxidation processes compared to the corresponding Fe-salt/CN catalysts, due to the promoted accessibility of USCAD Fe sites by the porous alveolate structure. This S-assisted method exhibits good feasibility in a large variety of S species (thiourea, S powder, and NH4SCN) and Fe salts, providing a new avenue for the low-cost and large-scale synthesis of high-density USCAD metal/g-C3N4 catalysts.

Ball milling modification was performed on Cs/X catalysts before or after cesium ion exchange. Multiple characterization results (such as pyridine-FTIR, XPS, and solid-state NMR) demonstrated that ball milling played a distinct role in these two different preparation procedures of the catalyst. Ball milling performed after the cesium modification has a strong influence on the Cs/X structure and acid–base properties, which results in the enhancement of the catalytic performance for side-chain methylation of toluene with methanol. Detailed studies revealed that ball milling intensified the interactions between oxides and molecular sieves, which not only increased the dispersion of the Cs species but also generated some weaker basic centers. It is proposed that the new basic centers could be Si–O–Cs and Al–O–Cs, which are produced by breaking of the Si–O–Al bonds of the zeolite framework under the synergetic effect of ball milling and alkali treatment. These new active sites may help to promote the side-chain methylation reaction. However, excessive ball milling will lead to the vanishing of zeolite micropores, thus deactivating side-chain methylation activity, which indicates that microporosity plays a key role in side-chain methylation and individual basic centers cannot catalyze this reaction.

Shape selectivity is the critical issue of molecular sieve catalysis. As an important aspect of shape-selective catalysis, the significance of diffusion in conversion, deactivation, and product sel...