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Lattice oxygen in metal oxides plays an important role in the reaction of diesel oxidation catalysts, but the atomic-level understanding of structural evolution during the catalytic process remains elusive. Here, we develop a Mn2O3/SmMn2O5 catalyst using a non-stoichiometric exsolution method to explore the roles of lattice oxygen in NO oxidation. The enhanced covalency of Mn–O bond and increased electron density at Mn3+ sites, induced by the interface between exsolved Mn2O3 and mullite, lead to the formation of highly active lattice oxygen adjacent to Mn3+ sites. Near-ambient pressure X-ray photoelectron and absorption spectroscopies show that the activated lattice oxygen enables reversible changes in Mn valence states and Mn-O bond covalency during redox cycles, reducing energy barriers for NO oxidation and promoting NO2 desorption via the cooperative Mars-van Krevelen mechanism. Therefore, the Mn2O3/SmMn2O5 exhibits higher NO oxidation activity and better resistance to hydrothermal aging compared to a commercial Pt/Al2O3 catalyst. This work reports on an exsolved Mn2O3/SmMn2O5 diesel oxidation catalyst competitive with current commercial materials in reactivity and hydrothermal aging resistance and further clarifies the catalytic mechanism for lattice oxygen as the reactive center [ABSTRACT FROM AUTHOR]

This study aimed to obtain paeonol with high purity by using the combination of steam distillation and antisolvent recrystallization (ASR) and to reduce the energy consumption and CO2 emission in the preparation process. First, different experimental parameters were optimized by response surface methodology (RSM). Under the optimal conditions, the purity and yield of the as‐obtained paeonol were about 98% and 56.97%, respectively. The physicochemical properties of purified paeonol were tested, showing consistency with those of standard paeonol. The energy consumption and CO2 emission of the preparation process of ASR and single‐solvent recrystallization were also investigated. Results showed that the energy consumption and CO2 emission of ASR were about 4.41 J/mg and 0.006 kg/mg, respectively, which were 6.89 J/mg and 0.0095 kg/mg lower than those of ethanol recrystallization, respectively, and 50.22 J/mg and 0.0144 kg/mg lower than methanol those of recrystallization, respectively. The above results showed that ASR could obtain paeonol with high purity in a high‐efficiency, low‐energy, and environmentally protective manner. [ABSTRACT FROM AUTHOR]

Aim: To formulate and assess the anticancer effect of the poly(lactic-co-glycolic acid) (PLGA) copolymer with the thioether groups (diethyl sulfide [Des]) and disulfide bond (cystamine containing disulfide [Cys]), which encapsulated the anticancer drug paclitaxel (PTX) and triggered PTX release in cancer cell H2O2-rich or glutathione-rich surroundings. Methods: PLGA-b-P (Des@Cys) and PLGA-b-P nanoparticles loaded with PTX were prepared and characterized in vitro. The delivery ability of the PLGA-b-P nanoparticles and PLGA-b-P-PTX nanoparticles was assessed on a CT26 (mouse colon cancer cell line) and mouse lung cancer LLC model. Results: The nanoparticles were successfully prepared. Compared with free PTX, the formulated PLGA-b-P nanoparticles loaded with PTX exhibited greater accumulation at the tumor site in the mouse model. Conclusion: PLGA-b-P nanoparticles promote drug accumulation at tumor sites, providing an effective strategy for an intelligent, responsive drug-delivery system. Cancer is one of the diseases with the highest mortality rate in the world. Chemotherapy is the most frequently used method of cancer treatment. However, traditional chemotherapeutic drugs have the disadvantages of lack of specificity, high toxicity to the human body, lack of tumor targeting, inability to exist stably in the body, ease of clearance by the body and drug resistance to tumors, so clinical application is limited. Paclitaxel is widely used in the treatment of various cancers, and its use is limited due to the above disadvantages. The purpose of this study was to construct a nanodelivery system with dual responses to the tumor microenvironment, enabling the efficient accumulation of paclitaxel in solid tumors through the enhanced permeability and retention effect, enhancing the therapeutic effect of cancer. This study also investigated the intravenous safety of this dual-responsive nanodelivery system. It evaluated the toxic effects of drug-loaded nanoparticles on cancer cells and validated the controlled release of nanoparticles at tumor sites by in vivo imaging in mice. The authors concluded that tumor microenvironment dual-responsive nanoparticles are a novel and promising nanodelivery system as an intelligently responsive anticancer agent with great promise in future clinical trials. This study prepared polymer nanocarriers (PLGA-b-p-NPs) with double response to the tumor microenvironment and loaded with traditional antitumor drug paclitaxel, so that drugs can accurately reach tumor cells and be rapidly released in cells. [ABSTRACT FROM AUTHOR]

Amphiphilic polymer micellar carriers are the most commonly used nanocarriers for oral delivery of hydrophobic drugs because their hydrophilic shell can avoid the recognition of the reticuloendothelial system (RES), has excellent drug-carrying capacity, and protect the drug from inactivation in the gastrointestinal fluid. The polymer micelle shell can enter cancer cells by endocytosis, and autophagy in cells, degradation by lysosomal pathway, so as to release drugs, prolong the circulation time of drugs in vivo, and then achieve the effect of drug sustained release. In this study, the glutathione-responsive PLGA-ss-PEG loaded paclitaxel (PTX) micelles (PLGA-ss-PEG-PTX) were developed for anticancer therapy. With its long-term circulation and EPR (enhanced permeability and retention) effect, and the micelle had disulfide bond, which could be used as the recognition group of tumor microenvironment, so that the PLGA-ss-PEG-PTX could specifically accumulate at the tumor site, so as to produce better anti-tumor effect. The PLGA-ss-PEG-PTX was formulated by the emulsification method in this study. The drug loading was about 21.54%, the entrapment efficiency was about 94.2%, and the particle size range was about 90 nm with narrow particle size distribution. Cytotoxicity and embryonic toxicity experiments were carried out using mouse lung cancer cells (LLC) and zebrafish fertilized eggs. It was proved that the low concentration of blank micelles had little cytotoxicity, but high concentration of blank micelles had adverse effects on zebrafish embryonic development, resulting in embryonic malformation. The uptake of drugs by cancer cells was studied by a high connotation cell imaging analysis system. The experiments showed that the drug molecules encapsulated in micelles could achieve higher uptake by cells compared with free drug molecules. In addition, in the in vivo evaluation experiment of drugs, the PLGA-ss-PEG-PTX could significantly enhance the therapeutic effect of the PTX, improve its water solubility, and improve its oral bioavailability. [ABSTRACT FROM AUTHOR]

Tartary buckwheat, a healthy food, is associated with a reduced risk of certain human chronic diseases. However, the bioactive component flavonoids in Tartary buckwheat have poor solubility and low absorption in vivo. To improve these points, 60.00% Tartary buckwheat total flavonoids (TFs) were obtained by ethanol refluxing method, which were purified and micronized by antisolvent recrystallization (ASR) using methanol as a solvent and deionized water as an antisolvent. By using High Performance Liquid Chromatography (HPLC) and electrospray ionized mass spectrometry (ESI-MS), the main flavonoid in pure flavonoids (PF) were rutin (RU), kaempferol-3-O-rutinoside (KA) and quercetin (QU); the content of TF is 99.81% after purification. It is more worthy of our attention that micronized flavonoids contribute more to antioxidant activity because of good solubility. These results provide a theoretical reference for the micronization of other flavonoids. [ABSTRACT FROM AUTHOR]

[Display omitted] • LaFeO 3 with acid treatment (LFO-H) exhibited better CO oxidation performance to the raw material (LFO). • LFO-H possessed higher surface area, higher oxygen species concentration and better low-temperature reducibility. • LFO-H exhibited excellent thermal stability during the CO oxidation reaction. The rational design of low-cost catalysts with excellent catalytic activity is one of the most significant topics in heterogeneous catalysis. LaFeO 3 (LFO) perovskite was synthesized by the citrate sol-gel method and followed through a selective dissolution method by acid solutions. The surface element percentage, chemical states and pore structure of LFO were tuned. The acid-treated catalyst (LFO-H) showed higher activity in CO oxidation than the raw LFO. In terms of various characterizations, the exposed La ions of the LFO were slightly etched by dilute nitric acid, but the LFO-H still preserved the original perovskite framework. The corresponding surface area, surface oxygen vacancies and reducibility were also improved after acid treatment, accounting for its higher catalytic activity. Moreover, the LFO-H also exhibited excellent thermal stability because the perovskite structure remains after acid treatment. [ABSTRACT FROM AUTHOR]

Two different hollow structured Co3O4 micro-polyhedrons, derived from Zeolitic imidazolate frameworks (ZIF)-67 crystals, were fabricated by tuning the synthetic strategy (positive or reverse addition). The results demonstrate that the synthetic strategy significantly affect catalyst structure and properties. Compared with Co3O4-A nanocatalyst, the Co3O4-B nanocatalyst exhibit superior catalytic performance, showing 100% CO conversion at the conditions of T = 110 °C and SV = 30,000 h−1. The higher catalytic performance could be attributed to its higher surface area, lower temperature reducibility, and abundant surface Co3+ and adsorbed oxygen. Two different hollow structured Co3O4 micro-polyhedrons, derived from Zeolitic imidazolate frameworks (ZIF)-67 crystals, were fabricated by tuning the synthetic strategy (positive or reverse addition). The Co3O4-B nanocatalyst exhibit superior catalytic performance, which should be attributed to its higher surface area, lower temperature reducibility, and abundant surface Co3+ and adsorbed oxygen. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • LaCo 0.65 Ga 0.35 O 3 was loaded on ZrO 2. • Co NPs was confined by the mixed oxides of La-Ga-O after reduction. • Ga-doping made cobalt in positive charge, which is beneficial to C 2+ OH generation. • The catalyst showed excellent ethanol selectivity and stability. Abstract In this work, a series of catalysts of LaCo 1-x Ga x O 3 with perovskite phase supported on ZrO 2 was prepared by combining the citrate complexing method with incipient impregnation. The catalysts of LaCoO 3 /ZrO 2 and Co 3 O 4 -Ga 2 O 3 /ZrO 2 were similarly prepared and used for comparison. The catalysts were characterized by using BET, XRD, H 2 -TPD, H 2 -TPR, CO-TPD, TG, XPS and TEM techniques. Reducing LaCo 1-x Ga x O 3 /ZrO 2 resulted in forming mixed oxides of La-Ga-O modified Co/ZrO 2 , which was used as the catalyst for higher alcohols synthesis from syngas. The prepared catalyst exhibited very high selectivity to higher alcohols especially to ethanol, high resistance to sintering, high resistance to carbon deposition and good activity, which are attributed to Ga-doping made Co in positive charge, the confinement of mixed oxides of La-Ga-O for Co nanoparticles, the restriction of Ga-doping for carbon formation and the high dispersion of Co nanoparticles, respectively. [ABSTRACT FROM AUTHOR]

Considering the radius similarity of Al3+ (0.50 Å) and Ga3+ (0.62 Å), Al−Co and Ga−Co layered double hydroxides (LDH) was prepared as precursor to improve the synergetic interaction of the transition metals. The Al−Co and Ga−Co spinel catalysts were obtained by the following calcination for the toluene oxidation. The Ga−Co (Ea=79.5 kJ mol−1) showed higher activity than the Al−Co (Ea=95.4 kJ mol−1), and it exhibited excellent stability and resistance to carbon deposition during a 50 h reaction period at 300 °C. Characterization results indicated that the improved activity of Ga−Co spinel could be attributed to the higher reducibility (H2‐TPR), more surface Co3+ and adsorbed oxygen in quantity (XPS) and adsorbed toluene (Toluene‐TPD) than Al−Co spinel. Compared with traditional Ga−Co binary catalyst, the spinel structure possessed more B‐sites cations outermost of the surface and surface oxygen vacancies for the toluene adsorption and ring‐open reaction. It′s all about how big you are: Considering the radius similarity of Al3+ (0.50 Å) and Ga3+ (0.62 Å), Al−Co and Ga−Co LDH were prepared as precursor to improve the synergetic interaction of the transition metals. The Al−Co and Ga−Co spinel were obtained by the following calcination for the toluene oxidation. Characterization results indicated that the improved activity of Ga−Co spinel could be attributed to the higher reducibility, more surface Co3+ and adsorbed oxygen in quantity and adsorbed toluene than Al−Co spinel." [ABSTRACT FROM AUTHOR]

The catalyst for direct ethanol synthesis (DES) from syngas was investigated in this work, which is Co/La 2 O 3 -doped La 4 Ga 2 O 9 . The catalyst was prepared by using LaCo 1−x Ga x O 3 with perovskite phase as the precursor to intensify the interaction in the elements of Co, La and Ga. The catalysts were characterized by using XRD, H 2 -TPR, TEM, EDS, XPS, BET, ICP and TG techniques. This catalyst showed high selectivity to ethanol and excellent stability including excellent resistance to sintering and carbon deposition. It seems that the ethanol is generated in the interface between metallic Co and La 4 Ga 2 O 9 , and in the interface cobalt would be positively charged due to the interaction between Co nanoparticles and La 4 Ga 2 O 9 . The results and the related discussions indicate that Co/La 2 O 3 -doped La 4 Ga 2 O 9 catalyst is a promising catalyst for DES from syngas. Graphical abstracts. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic γ‐Fe2O3 catalysts were prepared by microwave‐assisted coprecipitation utilizing the direct‐titrate and back‐titrate precipitation technique with different precipitants, namely, (NH4)2CO3, NaOH, Na2CO3, and NH4OH, which were evaluated in the selective catalytic reduction of NOx with NH3. The optimum γ‐Fe2O3 catalyst preparation method was direct titration with NH4OH as the precipitant, which exhibits high deNOx efficiency. This direct titration was effective to maintain the proper crystallization degree of γ‐Fe2O3, improve the pore structure, and suppress the formation of α‐Fe2O3 phase, being advantageous to get tiny and uniform discrete γ‐Fe2O3 particles with high activity in selective catalytic reduction. NH4+‐based precipitants in direct titration leads to an increase of the surface O/Fe atom ratio, and more lattice oxygen sites are exposed to the crystal surface. [ABSTRACT FROM AUTHOR]

Abstract: Cu−Co based catalysts for ethanol synthesis (ES) directly from syngas requires that copper and cobalt should be in alloy state or in close contact with each other, the chemical state of the bimetallic Cu−Co should be tailored by more than one additives and the group composed of Cu−Co and the additives should be loaded on a support with high surface area. In this work, a strategy for design and preparing such kind of complex catalysts was proposed, by means of loading nano crystallites of La1‐xYxCo1‐yCuyO3 with perovskite phase on SiO2 and then reducing La1‐xYxCo1‐yCuyO3/SiO2. In a nano crystallite of La1‐xYxCo1‐yCuyO3, the ions of copper and cobalt are uniformly mixed at the atomic level and confined in the nano space, favoring the interaction between the reduced products of Cu, Co, La2O3 and Y2O3. Thus, prepared catalyst showed very good catalytic performance for ES. This preparation strategy should be extendable. [ABSTRACT FROM AUTHOR]

Hesperetin (HES) is a key biological active ingredient in citrus peels, and is one of the natural flavonoids that attract the attention of researchers due to its numerous therapeutic bioactivities that have been identified in vitro. As a bioenhancer, piperine (PIP) can effectively improve the absorption of insoluble drugs in vivo. In the present study, a cocrystal of HES and PIP was successfully obtained through solution crystallization. The single-crystal structure was illustrated and comprehensive characterization of the cocrystal was conducted. The cocrystal was formed by two drug molecules at a molar ratio of 1:1, which contained O–H–O hydrogen bonds between the carbonyl and ether oxygen of PIP and the phenolic hydroxyl group of HES. In addition, a solubility experiment was performed on powder cocrystal in simulated gastrointestinal fluid, and the result revealed that the cocrystal improves the dissolution behavior of HES compared with that of the pure substance. Furthermore, HES's bioavailability in the cocrystal was six times higher than that of pristine drugs. These results may provide an efficient oral formulation for HES. [ABSTRACT FROM AUTHOR]

• α‐MnO 2 -like catalyst was synthesis via acid selective dissolution strategy. • α‐MnO 2 -like catalyst possessed abundant oxygen species and better low-temperature reducibility. • α‐MnO 2 -like catalyst exhibited better benzene oxidation performance to the commercial Pt-based catalyst. • α‐MnO 2 -like catalyst exhibited excellent thermal stability. The elimination of benzene, a typical volatile organic pollutant, is one of the most challenging topics for environmental scientists. Catalytic oxidation technology is considered the most efficient approach for its elimination. Herein, we report the successful preparation of a novel α–MnO 2 –like rod catalyst via an acid etching route and propose YMn 2 O 5 mullite as a novel precursor. The optimized α–MnO 2 –like rod catalyst showed significantly improved benzene oxidation activity compared to the raw YMn 2 O 5 and commercial MnO 2 catalysts, resulting in 100 % benzene conversion at 200 °C at a GHSV of 60,000 mL g–1 h–1. Notably, the α–MnO 2 –like rod catalyst performance at lower temperatures (100–175 ℃) exceeded that of a commercial Pt/Al 2 O 3 catalyst. The excellent catalytic performance of the α–MnO 2 –like rod catalyst is associated with its low–temperature reducibility and abundant surface–active oxygen species. During the acid etching process, more Mn3+ is oxidized to Mn4+, and more surface oxygen vacancies are generated on the α–MnO 2 –like rod catalyst, which provides more adsorption sites for oxygen molecules to promote the benzene oxidation reaction. The α–MnO 2 –like rod catalyst should be a great alternative to commercial noble metal catalysts for the elimination of volatile organic pollutants, especially at lower temperatures. [ABSTRACT FROM AUTHOR]

Paclitaxel (PTX) is a poor water-soluble antineoplastic drug with significant antitumor activity. However, its low bioavailability is a major obstacle for its biomedical applications. Thus, this experiment is designed to prepare PTX crystal powders through an antisolvent precipitation process using 1-hexyl-3-methylimidazolium bromide (HMImBr) as solvent and water as an antisolvent. The factors influencing saturation solubility of PTX crystal powders in water in water were optimized using a single-factor design. The optimum conditions for the antisolvent precipitation process were as follows: 50 mg/mL concentration of the PTX solution, 25 °C temperature, and 1:7 solvent-to-antisolvent ratio. The PTX crystal powders were characterized via scanning electron microscopy, Fourier transform infrared spectroscopy, high-performance liquid chromatography–mass spectrometry, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, Raman spectroscopy, solid-state nuclear magnetic resonance, and dissolution and oral bioavailability studies. Results showed that the chemical structure of PTX crystal powders were unchanged; however, precipitation of the crystalline structure changed. The dissolution test showed that the dissolution rate and solubility of PTX crystal powders were nearly 3.21-folds higher compared to raw PTX in water, and 1.27 times higher in artificial gastric juice. Meanwhile, the bioavailability of PTX crystal increased 10.88 times than raw PTX. These results suggested that PTX crystal powders might have potential value to become a new oral PTX formulation with high bioavailability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microfibrous-structured Cu-ZSM-5/Al-fiber catalysts with different Si/Al molar ratios were synthesized for SCR reaction. • Adsorbed bridged nitrates species is in accordance with the enhanced NO degradation activity. • Microstructured Cu-ZSM-5 catalysts are more active at high-throughout conditions due to the enhanced mass transfer. Selective catalytic reduction of NO x with NH 3 (NH 3 -SCR) is one of the most efficient technologies to remove NO x emissions. The copper ion-exchanged zeolites with broad temperature windows and high N 2 selectivity are very promising for this process. In this work, we synthesized a series of microfibrous-structured Cu-ZSM-5/Al-fiber catalysts for SCR reaction by changing the Si/Al molar ratios. The in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of NH 3 adsorption results show that the Cu-ZSM-5/Al-fiber catalysts with higher Si/Al molar ratios have higher NH 3 adsorption capacity. The subsequent NO adsorption results show that the amount of adsorbed bridged nitrates species is in accordance with the enhanced NO x degradation activity. At moderate temperature, Cu-ZSM-5/Al-fiber catalyst shows better NH 3 -SCR performance under higher gas hourly space velocity (GHSV), indicating microstructured Cu-ZSM-5 catalysts are more active at high-throughout conditions due to the enhanced mass transfer. [ABSTRACT FROM AUTHOR]

Phloretin loaded porous starch (Ph-PS) were prepared for its application in food. The effects of Ph-PS in vitro release and its ability against AAPH-induced oxidative stress in vivo zebrafish model were investigated. Ph-PS was prepared by absorption method, the physical and chemical characterization showed that PS decreased the crystallinity of Ph obviously. Ph-PS exhibited higher release amount and faster release rate of Ph compared to free Ph in vitro release study. What's more, the effect of Ph-PS reduced ROS generation and lipid peroxidation was better than that of free Ph in zebrafish model. These findings suggest Ph-PS is a new and simple strategy to improve dissolution rate and antioxidant ability of Ph. In this paper: • Phloretin loaded porous starch were prepared by physical absorption method, the crystallinity of Ph decreased obviously. • Ph-PS exhibited higher release amount and faster release rate of Ph in vitro release study compared to free Ph. • The effect of Ph-PS reduced ROS generation and lipid peroxidation was better than that of free Ph in zebrafish model. [ABSTRACT FROM AUTHOR]

Titanium modified FeMgOx catalysts with different precursors were prepared by coprecipitation method with microwave thermal treatment. The iron precursor is a key factor affecting the surface active component. The catalyst using FeSO4 and Mg(NO3)2 as precursors exhibited enhanced catalytic activity from 225 to 400 °C, with a maximum NOx conversion of 100%. Iron oxides existed as γ-Fe2O3 in this catalyst. They exhibited highly enriched surface active oxygen and surface acidity, which were favorable for low-temperature selective catalytic reduction (SCR) reaction. Besides, it showed advantage in surface area, spherical particle distribution and pores connectivity. Amorphous iron-magnesium-titanium mixed oxides were the main phase of the catalysts using Fe(NO3)3 as a precursor. This catalyst exhibited a narrow T90 of 200/250–350 °C. Side reactions occurred after 300 °C producing NOx, which reduced the NOx conversion. The strong acid sites inhibited the side reactions, and thus improved the catalytic performance above 300 °C. The weak acid sites appeared below 200 °C, and had a great impact on the low-temperature catalytic performance. Nevertheless, amorphous iron-magnesium-titanium mixed oxides blocked the absorption and activation between NH3 and the surface strong acid sites, which was strengthened on the γ-Fe2O3 surface. [ABSTRACT FROM AUTHOR]

• WO 3 were deposited on CeO 2 nanocubes (C), nanoparticles (P), and nanorods (R). • The W@Ce-P showed the best SCR activity with considerable resistance to H 2 O & SO 2. • The W@Ce-P performed good NH 3 adsorption properties and exhibited more surface O2−. • The surface reducibility and acidity of the W@Ce-P catalyst were enhanced. An environmental benign WO 3 Blanketed CeO 2 catalyst, the W@Ce, was prepared via a two-step hydrothermal impregnation method for the NO x removal. The WO 3 was deposited on CeO 2 nanocube (C), nanoparticle (P), and nanorod (R). The W@Ce-P exhibited the highest SCR activity below 300 °C with considerable resistance to H 2 O and SO 2. Compared with the W@Ce-C and W@Ce-R, the NO conversion (at 200 °C) of the W@Ce-P increased by 11% and 38%, respectively. The W@Ce-P were mainly dominated with the (111) facets which have the highest SCR activity. Meanwhile, the W@Ce-P performed good adsorption properties of ammonia at 125–450 °C, and exhibited more surface lattice oxygen O2− than that of the W@Ce-C and W@Ce-R. Thus, the surface reducibility and acidity were enhanced at lower temperature, which benefits the SCR reaction. The CeO 2 nanoparcles and WO 3 particles showed good interaction and had well-distributed and similar particle size. However, CeO 2 nanocubes did not interact well with WO 3 , besides, more cerium and tungsten species are at lower valence state on the surface of the W@Ce-R. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The objective of the present work aimed to explore the potential of bacterial cellulose (BC) for oral delivery of melatonin (MLT), a natural hormone that faces problems of low solubility and oral bioavailability. BC was hydrolyzed by sulfuric acid followed by the oxidation to prepare bacterial cellulose nanofiber suspension (BCNs). Melatonin-loaded bacterial cellulose nanofiber suspension (MLT-BCNs) was prepared by emulsion solvent evaporation method. The properties of freeze-dried BCs and MLT-BCNs were studied by Fluorescence microscopy (FM), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), X–ray diffraction (XRD), differential scanning calorimetry (DSC) and thermo gravimetric (TG). The results indicated that the fibers in BCNs became short and thin compared with BC, MLT in MLT-BCNs was uniformly distributed, both BCNs and MLT-BCNs have good thermodynamic stability. The MLT-BCNs showed more rapid dissolution MLT rates compared to the commercially available MLT in SGF and SIF, the dissolution of the cumulative release rate was about 2.1 times of the commercially available MLT. The oral bioavailability of MLT-BCNs in rat was about 2.4 times higher than the commercially available MLT. Thus, MLT-BCNs could act as promising delivery with enhanced dissolution and bioavailability for MLT after oral administration. [ABSTRACT FROM AUTHOR]

Surface lattice oxygen in metal oxides is a common participant in many chemical reactions. Given this, the structural design of catalysts to activate lattice oxygen and moreover investigations into the effect of lattice oxygen on reaction pathways are hot topics. With this in mind, herein we prepare CuO-Zn 1- x Cu x O (ZCO) nanofibers akin to the Trojan horse legend and via an in situ reduction obtain activated Cu/Zn 1- x Cu x O (Cu/ZCO) nanofibers. X-ray absorption spectroscopy and X-ray photoelectron spectroscopy reveal that surface lattice oxygen of Cu/ZCO is effectively activated from inert O 2- to reactive O 2- x . This activation stems from the enhanced covalence of metal-oxygen bonds and the electron transfer between Cu and the support. Online mass spectrometry reveals that Cu/ZCO with activated lattice oxygen exhibits a higher Mars-van Krevelen reaction efficiency during the CO oxidation process. This study offers a new avenue to engineer interface interactions, given, as highlighted here, the importance of surface lattice oxygen in oxide supports during the catalytic process.

A diesel oxidation catalyst (DOC) is installed upstream of an exhaust after-treatment line to remove CO and hydrocarbons and generate NO 2 . The catalyst should possess both good oxidation ability and thermal stability because it sits after the engine. We present a novel high-performance DOC with high steam resistance and thermal stability. A selective dissolution method is adopted to modify the surface physicochemical environment of CeO 2 -SmMn 2 O 5 . The X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, Raman, electron paramagnetic resonance, hydrogen temperature-programmed reduction, and temperature-programmed desorption results reveal that surface Sm cations are partially removed with the exposure of more Mn 4+ and Ce 3+ cations and the presence of active surface oxygen species. This mechanism benefits the oxygen transformation from Ce to Mn and promotes the Ce 3+ + Mn 4+ ↔ Ce 4+ + Mn 3+ redox cycle according to the in situ near-ambient pressure X-ray photoelectron spectroscopy and in situ diffuse reflectance infrared Fourier transformation spectroscopy results. Under laboratory-simulated diesel combustion conditions, the catalyst demonstrates excellent low-temperature oxidation catalytic activity (CO and C 3 H 6 conversion: T 100 = 250 °C) compared to a Pt-based catalyst (CO and C 3 H 6 conversion: T 100 = 310 °C) with a WHSV of 120,000 mL g -1 h -1 . Specifically, NO conversion reaches 68% when the temperature is approximately 300 °C.