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Secondary pollution remains a critical challenge for the catalytic destruction of chlorinated volatile organic compounds (CVOCs). By employing experimental studies and theoretical calculations, we provide valuable insights into the catalytic behaviors exhibited by ceria rods, cubes, and octahedra for monochloromethane (MCM) destruction, shedding light on the elementary reactions over facet-dependent CeO2. Our findings demonstrate that CeO2nanorods with the (110) facet exhibit the best performance in MCM destruction, and the role of vacancies is mainly to form a longer distance (4.63 Å) of frustrated Lewis pairs (FLPs) compared to the stoichiometric surface, thereby enhancing the activation of MCM molecules. Subsequent molecular orbital analysis showed that the adsorption of MCM mainly transferred electrons from the 3sand 4p* orbitals to the Ce 4f orbitals, and the activation was mainly caused by weakening of the 3sbonding orbitals. Furthermore, isotopic experiments and theoretical calculations demonstrated that the hydrogen chloride generated is mainly derived from methyl in MCM rather than from water, and the primary function of water is to form excess saturated H on the surface, facilitating the desorption of generated hydrogen chloride.

3D motion estimation from cine cardiac magnetic resonance (CMR) images is important for the assessment of cardiac function and the diagnosis of cardiovascular diseases. Current state-of-the art methods focus on estimating dense pixel-/voxel-wise motion fields in image space, which ignores the fact that motion estimation is only relevant and useful within the anatomical objects of interest, e.g., the heart. In this work, we model the heart as a 3D mesh consisting of epi- and endocardial surfaces. We propose a novel learning framework, DeepMesh, which propagates a template heart mesh to a subject space and estimates the 3D motion of the heart mesh from CMR images for individual subjects. In DeepMesh, the heart mesh of the end-diastolic frame of an individual subject is first reconstructed from the template mesh. Mesh-based 3D motion fields with respect to the end-diastolic frame are then estimated from 2D short- and long-axis CMR images. By developing a differentiable mesh-to-image rasterizer, DeepMesh is able to leverage 2D shape information from multiple anatomical views for 3D mesh reconstruction and mesh motion estimation. The proposed method estimates vertex-wise displacement and thus maintains vertex correspondences between time frames, which is important for the quantitative assessment of cardiac function across different subjects and populations. We evaluate DeepMesh on CMR images acquired from the UK Biobank. We focus on 3D motion estimation of the left ventricle in this work. Experimental results show that the proposed method quantitatively and qualitatively outperforms other image-based and mesh-based cardiac motion tracking methods.

Photocatalytic hydrodechlorination (HDC) is a promising method for eliminating chlorinated organic compounds (COCs) from water, but it requires catalysts with excellent water activation ability. Defect engineering is a feasible way to enhance the catalytic performance of photocatalysts by improving light adsorption, charge carrier dynamics, and surface reactions. Herein, a well-designed 0D/2D S-scheme heterojunction with favorable band structures and defective interfaces was constructed via defect tailoring on TiO2quantum dots (QDs) and the interface structure. The optimized catalyst Ni-TiO2–x/g-C3N4with 1% Ni doping after thermal treatment at 300 °C under nitrogen resulted in superior visible-light-driven activity in trichloroethylene (TCE) photocatalytic HDC, approximately an 18.2-fold increase as compared with g-C3N4. Ni doping and thermal-induced oxygen vacancies were verified to synergistically endow the catalyst with improved visible-light absorption efficiency, ameliorated charge separation and migration, and enhanced redox potential. Experimental and theoretical results showed that the synergy of multifold defects in promoting visible-light harvesting was mainly due to the characteristic multiple midgap states, in terms of different intermediate energy levels and narrowed bandgap. Furthermore, the contradicting effects of midgap states on photogenerated charge carrier dynamics were mediated by the defective S-scheme heterojunction, where the detrimental charge recombination relating to excessive defects was considerably inhibited via superior spatial charge separation and promoted surface redox reactions. The design of defect-engineered heterojunctions and the role of controlled defects in adjusting band structures provide valuable insights for creating highly efficient artificial photosystems in the visible region.

Ru-based catalysts have been extensively employed for the catalytic destruction of chlorinated volatile organic compounds (VOCs), but their versatility for other routine VOCs’ destruction has been less explored. Herein, we show that Ru-decorated SnO2/CeO2mixed oxides can sustain H2O and HCl poisonings and are endowed with extraordinary versatility for a wide range of VOCs’ destruction. Selective adsorption of Ru on the cassiterite SnO2and CeO2nanorods through a Coulomb force can rationally tune the oxidation and dechlorination centers on decorated catalysts, where the epitaxial growth of RuOxon top of SnO2is endowed with excellent dechlorination ability and that on CeO2is functional as an oxidation center; the latter could also activate H2O to provide sufficient H protons for HCl formation. Our developed Ru/SnO2/CeO2catalyst can steadily destruct mono-chlorobenzene, ortho-dichlorobenzene, trichloroethylene, dichloromethane, epichlorohydrin, N-hexane, ethyl acetate, toluene, and their mixtures at an optimum temperature of 300 °C, and its monolithic form is also functional at this temperature with few dioxins being detected in the off-gas. Our results imply that the Ru-decorated SnO2/CeO2catalyst can meet the demands of regenerative catalytic oxidation for the treatment of a wide range of VOCs from industrial exhausts.

It is imperative to develop multifunctional erosion and corrosion resistant coatings for compressor blades of aircraft engines in harsh environment. PVD (Physical Vapor Deposition) technology has the advances in processing erosion-resistant coatings; however, the performance of PVD coatings to combat corrosion depends on various coating defects. Determining and comparing the corrosion performances of PVD TiN/Ti coating and uncoated TC4 alloy was the main objective of present work. The 960 h salt spray corrosion and 116 h hot corrosion tests were conducted to simulate the grounding and working environments of the aircraft compressors. The corrosion mechanisms due to the coating defects such as pinhole, columnar boundary and large grain were analyzed based on the OM, Confocal microscope, electrochemical measurements, SEM, XRD and EDS results. Owing to the disordered state associated with the columnar boundary and the coating defect, nitrogen could be easily replaced by oxygen in the hot corrosion process, these structures were channels for fast diffusion of oxygen. Moreover, the Gibbs energy changes of Ti oxidation and TiN oxidation were thermodynamically calculated according to the working condition of aircraft compressors, and considerable research effort was focused on mapping out the phase diagram of Ti, TiN and high pressure gases. The findings of this research can provide insights into developing multifunctional coatings for future aircraft engines.

ABSTRACTDespite improvements in surgical resection and adjuvant chemotherapy, the prognosis and outcomes of patients with osteosarcoma remains poor due to the occurrence of metastasis or relapse. Monocyte chemoattractant protein-1-induced protein-1 (MCPIP1), a zinc-finger RNA-binding protein, is known to regulate inflammatory responses and repress breast cancer growth. However, the regulation of MCPIP1 by microRNAs has not been clearly elucidated in osteosarcoma. In this study, we found that miR-421 expression was upregulated and MCPIP1 expression was downregulated in the osteosarcoma specimens from patients. Moreover, MCPIP1 expression was inversely correlated with miR-421 expression in the clinical samples. Furthermore, the upregulation of miR-421 and downregulation of MCPIP1 resulted in poor overall survival and severe disease progression, respectively, in the patients with osteosarcoma. Bioinformatics analysis and luciferase reporter gene assays confirmed that miR-421 specifically targets and binds to the 3ʹ-UTR of MCPIP1. The overexpression of miR-421 induced cell proliferation, invasion, and migration, and the release of pro-inflammatory IL-6 in cultured human osteosarcoma cells. Additionally, the administration of miR-421 to tumor-bearing mice facilitated osteosarcoma growth by downregulating MCPIP1 expression. Taken together, these findings indicate that miR-421 is able to promote the development of osteosarcoma by regulating MCPIP1 expression, and can be a potential therapeutic target for osteosarcoma.

In order to overcome the problem that the prediction results of the existing topic heat prediction methods have large deviation, an online social network topic heat prediction method based on the single objective evolution method is proposed. This method uses the way of web crawler to obtain the network topic data, uses the principal component analysis method to calculate the weight of topic heat prediction index, obtains the expression of influence index, and constructs online through the single objective evolution method Social network topic heat prediction model framework, determine the model parameters, to achieve the prediction of topic heat. The experimental results show that the prediction method of online social network topic popularity guarantees that the deviation of prediction results is within 11.05, and the highest accuracy of trend prediction is 73.14, R2of video prediction is equal to 0.92, which has better prediction effect.

The properties of a series of imide oligomers were characterized according to their molecular weights, solubility, and thermal and rheological properties. This series of imide oligomers was synthesized viaa two-step method using 2,2′,3,3′-biphenyltetracarboxylic dianhydride(3,3′-BPDA) and aromatic diamines as the monomers, and 4-phenylethynyl phthalic anhydride(PEPA) as the end-capping agent. The imide oligomers based on 3,3′-BPDA showed excellent solubility in low boiling point solvents and low melt viscosity, which were attributed to their unique bent architectures. High-performance thermosetting polyimides were produced from these oligomers viathermal crosslinking of the phenylethynyl groups. The mechanical and thermal properties of the thermosets were studied using tensile testing, dynamic mechanical thermal analysis(DMTA), and thermogravimetric analysis(TGA). The 3,3′-BPDA-based thermosets exhibited excellent thermal properties, with glass transition temperatures of up to 455 °C, and 5% mass loss temperatures of up to 569 °C in air. The thermosets based on 3,3′-BPDA showed superior thermal properties compared to those derived from TriA-X series oligomers.

In this article, the underlying effect of phosphoric acid etching and additional water vapor on chlorine desorption behavior over a model catalyst La3Mn2O7was explored. Acid treatment led to the formation of LaPO4and enhanced the mobility of lattice oxygen of La3Mn2O7evidenced by a range of characterization (i.e., X-ray diffraction, temperature-programmed analyses, NH3–IR, etc.). The former introduced thermally stable Brönsted acidic sites that enhanced dichloromethane (DCM) hydrolysis while the latter facilitated desorption of accumulated chlorine at elevated temperatures. The acid-modified catalyst displayed a superior catalytic activity in DCM oxidation compared to the untreated sample, which was ascribed to the abundance of proton donors and Mn(IV) species. The addition of water vapor to the reaction favored the formation and desorption of HCl and avoided surface chlorination at low temperatures. This resulted in a further reduction in reaction temperature under humid conditions (T90of 380 °C for the modified catalyst). These results provide an in-depth interpretation of chlorine desorption behavior for DCM oxidation, which should aid the future design of industrial catalysts for the durable catalytic combustion of chlorinated organics.

In this article, Sr2+and/or Fe3+-doped LaMnO3perovskites were rapidly synthesized using supercritical water (sc-H2O) in a continuous hydrothermal flow reactor. Nanosized perovskites (6–45 nm) with defective structures were obtained, which led to high surface areas (28–67 m2g−1) and enriched defects. After being subjected to catalytic toluene oxidation, La0.9Sr0.1Mn0.9Fe0.1O3exhibited superior activity with T50(i.e., the temperature of 50% toluene conversion) at approximately 213 °C, T90(i.e., the temperature of 90% toluene conversion) at approximately 236 °C, and the reaction rate constant, k, at 1.47 mL g−1s−1(at 180 °C). Such activity was even comparable to that of some noble metal catalysts. H2-TPR, O2-TPD and 18O2-TPSR analyses suggested that both the Langmuir–Hinshelwood and Mars–van Krevelen mechanisms are involved in such a toluene oxidation process, where the dissociation of gaseous oxygen (viathe surface oxygen vacancies) and the diffusion of mobile lattice oxygen (to the catalyst surface) in the lanthanide perovskites played a crucial role in determining their toluene oxidation efficiencies. This explained why La0.9Sr0.1Mn0.9Fe0.1O3that has enriched surface oxygen vacancies and high lattice oxygen mobility (both originating from the structural distortion in sc-H2O reaction) could yield a remarkable performance in catalytic toluene oxidation.

Noble metals, e.g.Pd, are often made into hybrid or composite catalysts (with less expensive materials) to oxidize industry-source emitted volatile organic compounds (VOCs) at low temperatures. In general, the loadings of these metals should be optimized to reduce costs whilst maintaining activity. There exists the possibility to obtain highly active catalysts with low loadings of noble metals by properly tuning the valence state of the metal(s). However, the relationship between the valence state and its effect on catalyst performance is still a matter of debate. In this article, we used supercritical water (sc-H2O), in the presence of oxidizing or reducing gases, as a feasible reaction medium to synthesize Pd/NiO hybrid nano-catalysts and in situmodify the valence state of Pd. After subjecting the catalysts to a range of analytical techniques, including XRD, H2-TPR, DRIFT, TPSR, etc., we unveiled that Pd0is more active than PdOxand metal oxides in the catalytic oxidation of toluene. This is mainly because the stabilized Pd0is capable of activating gaseous oxygen (and toluene) at low temperatures and returning to the original state by toluene even with excess oxygen. Although PdOxcould desorb active oxygen under a reducing atmosphere and might assist in the oxygen spillover from NiO, it is difficult to convert into Pd0in an oxygen-rich environment. The developed Pd0-dominated catalyst was found to be robust and highly active after an ageing test with and without water vapour.

Layered perovskites possess frameworks that can sustain a larger extent of oxygen nonstoichiometry than perovskites, which makes them possibly more suitable for catalytic applications. However, there is little work in literature concerning the catalytic behaviors of them. In this paper, Lan+1NinO3n+1layered perovskites were selected as potential catalysts for catalytic oxidation of toluene and methane. The activation and transmission of active oxygen species over the layered structure were explored by using a range of analytical techniques, e.g., O2-TPD, XPS, and H2-TPR. It was noted that the LaNiO3(n= ∞) that possessed the most chemisorbed oxygen species had the lowest activation energy (Ea, ca. 70.1 kJ mol–1) in toluene oxidation and the La4Ni3O10(n= 3) that owned a superior lattice oxygen mobility showed the lowest Ea(ca. 111.0 kJ mol–1) in methane oxidation. The La2NiO4(n= 1) that lacked chemisorbed and superficial lattice oxygen species yielded the highest Eain either toluene or methane oxidation. It is expected that the work conduct herein could generate more awareness onto the potential catalyst application for layered perovskites and would also give promising insights into the correlation between structural framework and catalytic behaviors for extraordinary materials.

An improved fundamental understanding of active site structures can unlock opportunities for catalysis from conceptual design to industrial practice. Herein, we present the computational discovery and experimental demonstration of a highly active surface-phosphorylated ceria catalyst that exhibits robust chlorine tolerance for catalysis. Ab initio molecular dynamics (AIMD) calculations and in situnear-ambient pressure X-ray photoelectron spectroscopy (in situNAP-XPS) identified a predominantly HPO4active structure on CeO2(110) and CeO2(111) facets at room temperature. Importantly, further elevating the temperature led to a unique hydrogen (H) atom hopping between coordinatively unsaturated oxygen and the adjacent P═O group of HPO4. Such a mobile H on the catalyst surface can effectively quench the chlorine radicals (Cl•) via an orientated reaction analogous to hydrogen atom transfer (HAT), enabling the surface-phosphorylated CeO2-supported monolithic catalyst to exhibit both expected activity and stability for over 68 days during a pilot test, catalyzing the destruction of a complex chlorinated volatile organic compound industrial off-gas.