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This paper investigates the method for water ingress detection in an aluminum honeycomb sandwich structure by laser ultrasonics. To clarify the propagation of Scholte waves generated at the solid-liquid interface, the theoretical dispersion curves in the water-aluminum layered structure are calculated by the global matrix method. Using a laser ultrasonic visualizing inspector, the guided wave propagation in the wavefields has been visualized, which shows the mode conversion behaviors occurring in the water ingress area. The clarification of mode conversion is then investigated by the finite element method. The Scholte modes at the solid-fluid interface and the Lamb modes in the face sheet are interconverted because of the change in the waveguide structure. Wavenumber filter reconstruction and the resulting energy maps are applied to illustrate the mode conversion in the wavefields and to detect the water ingress area. Results show that the appearance of the water layer contributes to the mode conversion behaviors during the guided wave propagation in the honeycomb sandwich structure, which offers the potential for water ingress detection based on the mode conversion behaviors. [ABSTRACT FROM AUTHOR]

Detecting disbonds in honeycomb sandwich structures using ultrasonics is challenging due to the complex wave propagation. This paper investigates the method for disbond quantification in honeycomb sandwich structures using laser ultrasonics. In the experiments on an aluminum specimen, the detection frequency range was determined by the local defect resonance (LDR) in the disbond regions. The energy maps of bandpass wavefields identified the locations of disbonds. To improve the results, a frequency-wavenumber analysis of the wavefields was performed. The wavenumber spectra were reconstructed by wavenumber filtering to strengthen the outline components for quantifying disbonds. Local cross-correlation (LCC) was proposed to show the outlines of disbonds and honeycomb cells, whose results agreed well with the X-ray imaging. Moreover, LCC could also quantify a disbond in the composite honeycomb sandwich structure. Consequently, combining energy maps and LCC results can effectively detect the locations and sizes of disbonds in honeycomb sandwich structures. [ABSTRACT FROM AUTHOR]

• Bipolar membrane ED was used for nutrient recovery from AD dewatering sidestream. • Concentrated acid and base streams containing separated nutrients were produced. • Ammonia was recovered using a produced acid solution by membrane stripping. • Phosphate was recovery as struvite or hydroxyapatite by chemical precipitation. • Nutrient recovery was achieved with minimized chemical and energy inputs. Anaerobic digestion (AD) offers an efficient means for treating sludge generated in wastewater treatment plants (WWTPs), but nutrient-rich AD dewatering sidestream contributes as much as 30 % of the overall nutrient loading of WWTPs. Several electrochemical approaches are being developed as a sidestream treatment strategy to prevent return of nutrients to WWTP headworks and recover them for fertilizer production. One such method is to produce acids and bases, essential chemicals necessary to facilitate nutrient recovery, using bipolar membrane electrodialysis (BMED). In this study we show simultaneous separation of nutrients and production of acid/base streams with an additional consideration for increasing the concentration of ammonium and phosphate in the final product stream by systematically altering compartment flow rates and hence the retention time of each stream. Using a three-compartment BMED system with a synthetic sidestream containing 50 mM NH 3 -N and 2 mM PO 4 -P, we achieved up to 80 % ammonia removal (via a cation exchange membrane) and up to 60 % phosphate removal (via an anion exchange membrane) at a productivity of 34.2 L m−2 h−1. Separated ammonia was recovered (>90 %) in a subsequent membrane contactor (MC) that was fed with acid and base streams produced by the BMED unit. A phosphate recovery > 80 % was achieved by chemical precipitation (CP). In a combined BMED-MC-CP process, the concentrated final product contained 333.9 mM NH 3 -N and 3.1 mM PO 4 -P with an energy consumption of 8.9 kWh kg−1 N recovered. These results illustrate that the BMED-based treatment train is a promising strategy for nutrient recovery from AD dewatering sidestream. [ABSTRACT FROM AUTHOR]

Assemblies of β-iron oxyhydroxide (β-FeOOH) nanostructures were synthesized by a facile, mild, and non-toxic ultrasonication method. Quasi-rectangular, chrysanthemum-like, and silk-like architectures, respectively, were obtained by introducing a urea surfactant, synthesized Fe 3 O 4 template, and natural kapok seed template. This versatile and efficient synthetic method can be extended to the fabrication of a series of novel, multifunctional assembled architectures. Hierarchical structures with identical morphologies were constructed from porous β-FeOOH nanorods with high surface areas. The effects of the assembly mode on the nonlinear optical (NLO) properties of the β-FeOOH nanorod assemblies were explored using the open-aperture Z-scan technique. Individual β-FeOOH nanorods and their analogous nanoassemblies exhibited excellent NLO performances upon excitation at 532 and 1064 nm in the nanosecond laser pulse regime, both in liquid and sol–gel solid-state matrices. These nanomaterials are promising candidates for broadband optical limiters; however, their abilities to attenuate intense and potentially dangerous laser beams differ. Our results confirm that nanoassembly formation can be used to effectively tailor the NLO activities of β-FeOOH nanorods, and the possible mechanisms for these behaviors are discussed. The observed NLO effects originate from nonlinear scattering and free-carrier absorption at 532 and 1064 nm, respectively. This study provides new insights into the assembly of one-dimensional building blocks, which will be useful in the rational design and preparation of hierarchical materials and enable tailoring and improvement of the NLO properties of materials. [ABSTRACT FROM AUTHOR]

Akaganéite, with the formula FeO(OH,Cl), has potential in the realms of environmental protection, energy conversion/storage, and biomedicine. However, its large-scale production is still challenging in terms of cost and environmental friendliness, which limits its commercial application. In this study, we report a one-step sonochemical fabrication method to address this challenge. Fabrication has been performed in aqueous FeCl3 solutions with the aid of acoustic cavitation by gas bubbles. The fabricated FeO(OH,Cl) nanoparticles (NPs) are porous and exhibit spindle shapes. With increasing sonication time, these NPs can be spontaneously assembled to form irregular micro-/nanostructures of varied sizes. When required, such assemblies could be suitably directed by adding appropriate templates, either natural or artificial. The template-directed assembly relies on the principle of minimum free energy and the resulting FeO(OH,Cl) NPs nucleating and growing along the added templates. This study demonstrates a sonochemical fabrication method amenable to large-scale production, that is inexpensive and environmentally friendly, providing monodisperse porous FeO(OH,Cl) NPs of spindle shape and their various assemblies for commercial purposes. [ABSTRACT FROM AUTHOR]

• Nanoscaled Pd particles are deposited onto TiO 2 surface by photodeposition. • Pd/TiO 2 -P shows superior performance in the light-induced N -alkylation of piperazine with alcohols. • High proportion of Pd0 species facilitates intermediate hydrogenation. • The α-C–H cleavage of methanol to form hydroxymethyl radical is the rate-determining step. N -alkylated piperazines can be synthesized by the thermal catalytic alkylation of piperazine with alkyl halides or alcohols in the presence of supported metal catalysts. However, these processes either discharge large amounts of waste or require harsh conditions. Here, we report the results of N -alkylation of piperazine with lower alcohols (methanol, ethanol, and propanol) without external hydrogen addition at room temperature in the presence of a TiO 2 -supported Pd catalyst (Pd/TiO 2 -P) prepared by photodeposition method. Compared with the catalysts prepared by the conventional chemical reduction or hydrogen reduction, the Pd/TiO 2 -P catalyst showed the highest conversion of piperazine and the best selectivity to N -alkypiperazines. The mechanistic studies indicated that this phenomenon occurs via tandem photocatalytic reactions involving alcohol dehydrgenation to aldehyde, aldehyde condensation with piperazine to enamine, and enamine hydrogenation to N -alkylated piperazines. Considering the experimental results of methanol isotope kinetics, the α-C–H cleavage of methanol to form hydroxymethyl radical (·CH 2 OH) was proven to be the rate-determining step in the N -alkylation reaction of piperazine with low carbon alcohols. The characterization and control experiments revealed that the size of Pd nanoparticles and the valence of Pd species were vital to the reaction. The Pd/TiO 2 -P catalyst with an average of 2.5 ± 0.5 nm Pd particles and approximately 68% Pd0 species on surfaces presented the highest activity for the photocatalytic tandem reactions of methanol dehydrogenation and enamine hydrogenation. The photocatalytic N -alkylation of piperazine with alcohols has been studied in-depth over Pd/TiO 2 catalyst fabricated via photodeposition. [Display omitted] [ABSTRACT FROM AUTHOR]

Solubility of apatite is highly addressed in mineralogical and material studies. Heating is one of the major processes in apatite industry. In this study, synthesized hydroxylapatite (HAp), geological fluorapatite (FAp), and bone bioapatite (BAp) were heated at various temperatures (100–900 °C) for analyses. The mineralogy and solubility of the three apatites were analyzed by XRD, ATR–IR, and ICP. Release of Ca and P in water for BAp reaches the maximum when heated at 200 °C, i.e., 0.215 mmol/L for Ca and 0.106 mmol/L for P. The value is higher than the maximum values (heated at 900 °C) of the solubility for HAp and FAp. The heating temperature at 600 °C is a re-crystallization point for all the three types of apatites. Especially, the crystallinity of BAp is significantly elevated at > 600 °C. Phase of geological FAp is relatively stable during heating up to 900 °C. Phase of β-TCP is present when heating HAp at 800 to 900 °C. In addition, BAp is transformed to the resemblance of HAp. However, no β-TCP was detected for BAp during heating between 800 and 900 °C, which is probably due to its Ca-deficiency. This study elucidates the correlation of phase changes of BAp and its solubility during heating, which sheds the light on its application as materials and fertilizer. [ABSTRACT FROM AUTHOR]

• Two shields that each contain a collimator and simultaneously shield neutrons and gamma-rays are designed for neutron and gamma-ray diagnostics. • Monte Carlo simulations are used to determine the optimal materials and thicknesses of the shielding layers. • Replaceable collimation aperture adjustment modules are adopted, and the effects of the structure used are specifically analyzed. • For incident particles of different energies, the efficiency of the collimator is estimated. • The particle fluxes in the sensitive energy ranges of the detectors are used as the basis for evaluation. New compact radiation shields have been designed to reduce the scattered neutrons and background gamma-rays for neutron and gamma-ray diagnostics in the EAST hall. The design focused on optimizing radiation shielding performance versus volume and weight to fit the small amount of available space outside the tokamak device. Based on the Monte Carlo method and using the Geant4 tool kit, three-dimensional models of the shield were created for material selection and structural design optimization. The 10-cm and 15-cm polyethylene doped with 12 wt.% B 4 C, and 10-cm cast lead were finally selected for the main body of the shield. In addition, the shape and structure of the collimator in the front half of the shield are optimized, and a replaceable aperture adjuster module design has been adopted for the collimator. For incident particles with different energies, the collimation efficiency of the collimator has also been calculated. [ABSTRACT FROM AUTHOR]

N-doped carbons (NCs) have attracted considerable attention for their outstanding physicochemical properties, including tunable porosity, electronic features and modified surface. Here, we report the preparation of hierarchically porous NCs derived from the direct pyrolysis of ZIFs (ZIF-7 and ZIF-8) and poly– m –phenylenediamine-covered carbon black (P m PDA-C) for the stabilization of Cu nanoparticles (NPs). The configuration of N species can be effectively regulated by changing the ligand of ZIFs and pyrolysis atmosphere. A remarkable N configuration synergistic effect is observed in the oxy-carbonylation of methanol to dimethyl carbonate with molecular oxygen. The results indicate that the Cu NPs on pristine carbon have a turn over frequency (TOF) of 4.4 h−1 for the reaction, while those on NCs from ZIF-8 and ZIF-7 present TOF values as high as 17.9 h−1 and 28.5 h−1, respectively. The extensive characterizations reveal that NCs with a nitrogen content of 2–5 wt% and a pyrrolic-/pyridinic-N molar ratio of 2–3 are vital for the performance enhancement of Cu NPs. This work shows that the stabilization and enhanced performance of active Cu NPs on NCs are realized by the rational design of precursors to generate the proper N configurations. Image 1 • A series of NCs are prepared from ZIFs with N content in the range of 0–20 wt%. • The N configuration is regulated by ligand of ZIFs and varying pyrolysis conditions. • The performance of supported Cu catalysts is correlated with N configurations. • NCs with 2–5 wt% N and pyrrolic-/pyridinic-N ratio at 2–3 are vital for Cu catalysis. [ABSTRACT FROM AUTHOR]

• The Ag/Zr–SiO 2 catalyst is highly selective for producing unsaturated alcohol. • Significant support effect and interfacial catalysis are observed. • Enhanced acidity by zirconia doping promotes Ag dispersion and catalytic activity. • Interesting low-temperature O 2 chemisorption occurs on interfacial Ag sites. • Ternary Ag–ZrO 2 –SiO 2 interfaces favor the selective activation of C O bond. In gas-phase chemoselective hydrogenation of crotonaldehyde on Ag-based catalysts, zirconia doping on silica supports was found to improve catalytic performance in terms of unsaturated alcohol selectivity, hydrogenation activity, and stability. The surface modification of silica by zirconia doping favors the fine dispersion of Ag species due to the enhanced quantity and strength of surface acid sites, which enable construction of abundant catalytic sites effective for C O bond hydrogenation. High crotyl alcohol selectivity, exceeding 80%, and significant inhibition of monohydrogenation on the C C bond were observed on the optimal Ag/Zr–SiO 2 catalyst. Dynamic O 2 chemisorption measurement revealed that the pure Ag powders did not chemisorb O 2 irreversibly under 323 K, but SiO 2 or Zr–SiO 2 supported Ag catalysts did. The amounts of Ag active for O 2 chemisorption, which are at least one order of magnitude lower than that of surface Ag derived from TEM and XRD characterizations, match well with the perimeter interface Ag of hemispherical particles. A strong correlation between hydrogenation activity and O 2 uptake on those Ag/SiO 2 and Ag/Zr–SiO 2 catalysts with different Ag dispersions and deactivation degrees was observed, implying that the effective catalytic sites for crotonaldehyde chemoselective hydrogenation may originate from accessible interface sites with unique redox properties. Catalyst induction and deactivation were observed on both Ag/SiO 2 and Ag/Zr–SiO 2 catalysts in real catalytic operation. Changes in metal stable interface structure, rather than metal aggregation and coagulation, are assumed to be the main cause of irreversible catalyst deactivation, because the apparent Ag particle sizes changed slightly, but the oxygen chemisorption ability deteriorated considerably. Electropositive Ag sites interacting with neighboring oxygen from oxide supports at the ternary Ag–ZrO 2 –SiO 2 interface are proposed to account for highly selective C O bond hydrogenation to produce the desired unsaturated alcohol. [ABSTRACT FROM AUTHOR]

Phenol amination to various valuable amines has attracted considerable attention in heterogeneous catalysis, but limited studies have focused on non‐noble metal catalysts. This study reports a bifunctional catalyst (Ni/SiO2‐AE) containing nickel nanoparticles and Lewis acid sites derived from nickel phyllosilicates for efficient amination of phenol to cyclohexylamine. The Ni/SiO2‐AE catalyst resulted in 89.4% phenol conversion and 86.0% selectivity to cyclohexylamine at 160 °C for 2 h, which outperforms the catalysts by conventional deposition‐precipitation (Ni/SiO2‐DP) and wetness‐impregnation (Ni/SiO2‐WI). The turnover frequencies based on the actual exposed metal surface area for Ni/SiO2‐AE, Ni/SiO2‐DP, and Ni/SiO2‐WI are calculated as 71.7, 49.0, and 8.7 h−1, respectively. Results demonstrate that the Ni nanoparticles exsoluted from nickel phyllosilicates participate in the activation of dihydrogen molecules, and the Lewis acid sites stemmed from coordination unsaturated Ni2+ sites on the catalyst serve to adsorb and activate phenol. The synergistic effect of the dual‐functions intensifies the phenol amination. [ABSTRACT FROM AUTHOR]

Background: Previous studies have shown that the stress hyperglycemia ratio (SHR), a parameter of relative stress-induced hyperglycemia, is an excellent predictive factor for all-cause mortality and major adverse cardiovascular events (MACEs) among patients with ST-segment elevation myocardial infarction (STEMI). However, its association with pulmonary infection in patients with STEMI during hospitalization remains unclear. Methods: Patients with STEMI undergoing percutaneous coronary intervention (PCI) were consecutively enrolled from 2010 to 2020. The primary endpoint was the occurrence of pulmonary infection during hospitalization, and the secondary endpoint was in-hospital MACEs, composed of all-cause mortality, stroke, target vessel revascularization, or recurrent myocardial infarction. Results: A total of 2,841 patients were finally included, with 323 (11.4%) developing pulmonary infection and 165 (5.8%) developing in-hospital MACEs. The patients were divided into three groups according to SHR tertiles. A higher SHR was associated with a higher rate of pulmonary infection during hospitalization (8.1%, 9.9%, and 18.0%, P < 0.001) and in-hospital MACEs (3.7%, 5.1%, and 8.6%, P < 0.001). Multivariate logistic regression analysis demonstrated that SHR was significantly associated with the risk of pulmonary infection during hospitalization (odds ratio [OR] = 1.46, 95% confidence interval [CI] 1.06–2.02, P = 0.021) and in-hospital MACEs (OR = 1.67, 95% CI 1.17–2.39, P = 0.005) after adjusting for potential confounding factors. The cubic spline models demonstrated no significant non-linear relationship between SHR and pulmonary infection (P = 0.210) and MACEs (P = 0.743). In receiver operating characteristic curve, the best cutoff value of SHR for pulmonary infection was 1.073. Conclusions: The SHR is independently associated with the risk of pulmonary infection during hospitalization and in-hospital MACEs for patients with STEMI undergoing PCI. [ABSTRACT FROM AUTHOR]

Background: The Clínica Universidad de Navarra-Body Adiposity Estimator (CUN-BAE) index has been recommended as an ideal indicator of body fat and exhibited significant correlation with cardiometabolic risk factors. However, whether the CUN-BAE index correlates with incident diabetes in Asian populations is unknown. Therefore, this longitudinal study was designed to evaluate the association between baseline CUN-BAE index and type 2 diabetes mellitus (T2DM). Methods: This retrospective longitudinal study involved 15,464 participants of 18–79 years of age in the NAGALA (NAfld in the Gifu Area Longitudinal Analysis) study over the period of 2004–2015. Cox proportional hazards regression was performed to test the relationship between the baseline CUN-BAE index and diabetes incidence. Further stratification analysis was conducted to ensure that the results were robust. The diagnostic utility of the CUN-BAE index was tested by the receiver operating characteristic (ROC) curve. Results: Over the course of an average follow-up of 5.4 years, 373 (2.41%) participants developed diabetes. A higher diabetes incidence was associated with higher CUN-BAE quartiles (P for trend< 0.001). Each 1 unit increase in CUN-BAE index was associated with a 1.08-fold and 1.14-fold increased risk of diabetes after adjustment for confounders in males and females, respectively (both P < 0.001). Stratification analysis demonstrated a consistent positive correlation between baseline CUN-BAE and diabetes incidence. Moreover, based on ROC analysis, CUN-BAE exhibited a better capacity for diabetes prediction than both body mass index (BMI) and waist circumference (WC) in both sexes. Conclusions: The baseline CUN-BAE level was independently related to the incidence of diabetes. Increased adiposity determined by CUN-BAE could be used as a strong nonlaboratory predictor of incident diabetes in clinical practice. [ABSTRACT FROM AUTHOR]

Change detection is a fundamental problem in remote sensing image processing. Due to the great advantages in learning the knowledge representations and the complex relationship from large-scale datasets, deep learning has made great progress in change detection tasks in remote sensing community. However, most of the existing methods based on deep learning for change detection are implemented by learning differences of image pairs directly without paying considerations in influences of unstructured and temporal changes, or called nature changes, such as light and seasonal changes. In this paper, an end-to-end deep learning network for remote sensing image change detection is proposed, aiming to accurately detect the change of regions from a high-resolution image pair by learning prototype similarity, in which the metric learning is used and it is one of the meta-learning methods to learn change prototypes from support image pairs. The similarity between the query image pairs and the change prototypes can be measured by a learnable CNN metric. The experimental results based on the two public change detection datasets of high-resolution satellite images, CDD and BCDD, show that our proposed method performs better than other state-of-the-art change detection methods with an improvement of 3.5% and 0.4%, respectively. [ABSTRACT FROM AUTHOR]

• The neutron energy response of Cs 2 7LiYCl 6 :Ce (CLYC-7) scintillation detector was investigated, and the figures-of-merit (FOM), response function, and neutron energy resolution at different neutron energies were obtained. • The Monte Carlo method was used to simulate the particle transport within the CLYC-7 scintillator and investigate the energy response curves of different particles. • The response function was applied to the CLYC-7 scintillation detector, and it was used to measure the D-D fusion neutron spectrum on EAST. During plasma experiments on EAST (Experimental Advanced Superconducting Tokamak), the discharges heated with neutral beam injection (NBI) for plasma results in the production of 2.45 MeV deuterium-deuterium (D-D) fusion neutrons. In order to measure the energy spectrum of D-D fusion neutrons, a new Cs 2 7LiYCl6:Ce (CLYC-7) crystal with 7Li-enrichment has been developed and fabricated into a CLYC-7 scintillation detector. Before utilizing this detector for studying neutron energy spectra, it is crucial to explore the response function of the detector within a relevant neutron energy range. Therefore, the detector has been experimented using the 4.5 MeV electrostatic accelerator at Peking University to investigate its response to fast neutrons, energy resolution, and pulse discrimination capability in the neutron energy range 2.07 MeV–5.51 MeV. The neutron reactions occurring within the CLYC-7 scintillator were simulated using MCNPX, focusing on the reactions 35Cl(n,p) and 35Cl(n,α), as well as the energy response curve and the contributions of different particles (protons, alphas) to the neutron spectrum. The experimental results were successfully validated on EAST, where the 2.45 MeV fusion neutron energy spectrum was measured. That demonstrates the ability of the CLYC-7 scintillation detector to diagnose the fusion neutron energy spectrum for deuterium plasma discharge. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxidative oxidation of MG to MGO with O 2 is catalyzed by VO x / γ -Al 2 O 3. • The optimal catalyst achieves a stable MGO yield of approximately 63% for 300 h. • Polymerized VO x shows a higher MGO selectivity than isolated VO x and V 2 O 5. • The redox cycles of V4+ and V5+ are responsible for the production of MGO. The selective oxidation of methyl glycolate (MG) to methyl glyoxylate (MGO) using molecular oxygen in a fixed-bed reactor represents a greener and more efficient alternative to the traditional batch processing for producing this important fine chemical and intermediate. Despite its potential, detailed understanding of this catalytic reaction is still limited. In our study, VO x / γ -Al 2 O 3 catalysts were identified as effective for the reaction, but their performance strongly depended on the structure of VO x species. The optimal catalyst with nearly monolayer dispersed VO x achieved a high MG conversion of 91% and an MGO selectivity of 71%, alongside maintaining stability for 300 h without noticeable deactivation. At a low V loading of 0.6%, isolated VO x species were formed, exhibiting the highest turnover frequency (TOF) but the lowest MGO selectivity. Increasing the V loading to 3.9% resulted in a blend of less polymeric and isolated VO x species, which decreased the TOF but enhanced MGO selectivity to 59%. With the V loading ranging from 5% to 6.2%, monolayer dispersed VO x became dominant, yielding a lower TOF and the highest MGO selectivity. A further increase in V loading caused the emergence of crystalline V 2 O 5 , which seemed to act as a bystander. Moreover, the redox cycles of V4+ and V5+ over the VO x / γ -Al 2 O 3 catalyst played an important role in the selective oxidation of MG to MGO, while the overoxidation of MG to CO 2 might take place through the V3+/V4+ redox pairs, the extent of which was determined by the structure of VO x species. These insights are crucial for developing high-performance VO x -based catalysts for the production of MGO through the selective oxidation of MG. [ABSTRACT FROM AUTHOR]

Understanding of molecular diffusion mechanisms in zeolite plays a crucial role in the processes of adsorption and separations and can greatly facilitate the design of zeolite at molecular level. However, compared with the case of free gas phase, the diffusion behaviors in channel of zeolite are much more complicated due to the confined pore environments. To dig more detailed information about the diffusivity mechanism of gas molecules in the zeolite pore, diffusion behaviors of H 2 , He, N 2 , CH 4 and CO 2 molecules in the one-dimensional (1-D) channel of AlPO 4 -5 (AFI) zeolite-like materials were investigated using a combined classic molecular dynamics (MD) simulations and density functional theory (DFT) calculations. It is found that the diffusion behavior for light molecules (H 2 and He) at low loading in AlPO 4 -5 channel is more freedom because of their small molecular diameter and low energy variation (ΔE) in the longitudinal direction of the pore. Then, transport of light gas molecules can be described as Knudsen diffusion and the molecular mass plays a key role in this case. Transports of N 2 , CH 4 or CO 2 , with larger molecular diameter and higher ΔE value, were proposed to compete with surface diffusion and their diffusivity should be controlled by the adsorption energy between gas molecule and pore wall. Therefore, the diffusion degree of gas molecules at low loading is decreased as follows: H 2 > He > N 2 > CH 4 > CO 2. When the gas molecule loading increases, the gas diffusion freedom will be limited due to the increased gas-gas and gas-porous media collisions. Thus, the diffusion of these gas molecules with higher concentration is dominated by the gas-gas and the gas-AFI interactions. DFT calculation results demonstrate that both gas-gas and the gas-AFI interaction energies depend on their van der Waals diameter. As a result, the diffusion of these gas molecules at higher loading in AlPO 4 -5 channel is decreased as: He > H 2 > N 2 > CH 4 > CO 2. Our results confirmed that the diffusivity of gas molecules within the 1-D channel of AlPO 4 -5 is controlled by the molecular mass or gas-wall interactions at low loading, while is dominated by the gas-gas/gas-wall interactions at high loading. [Display omitted] • DFT calculation results confirmed that AlPO 4 -5 unit cell with P 1 symmetry is much more stable than that with P 6 cc symmetry. • Transport of light gas molecules (H 2 and He) with small d m and low ΔE at low loading in AlPO 4 -5 channel can be described as Knudsen diffusion and the molecular mass plays a key role in this case. • Transports of N 2 , CH 4 and CO 2 , with larger molecular diameter and higher ΔE value, at low loading in AlPO 4 -5 channel were considered as surface diffusion and their diffusivity should be controlled by the gas-AFI interactions. • The diffusion of these gas molecules in AlPO 4 -5 channel with higher concentration is dominated by the gas-gas and the gas-AFI interactions. [ABSTRACT FROM AUTHOR]

• The impact of the gamma irradiation environment in a fusion reactor on the electronic systems was introduced, and experimental verification was conducted through long-term Co-60 gamma irradiation experiments. • Gamma irradiation provides valuable reference for the design of electronic systems in fusion reactors. • Verified the operational condition of some chips under a long-term gamma irradiation environment (2000 Gy). • Provides reference for the verification of radiation resistance of electronic systems in a fusion reactor environment. In the environment of a fusion reactor, electronic systems are subjected to various influences including vibration, electromagnetic pulses, as well as irradiation from neutrons and gamma rays. Diagnostics systems on fusion reactors can accumulate radiation doses to a level where issues such as signal attenuation and system interruption can occur. Additionally, maintenance of electronic systems during fusion reactor experiments is often not feasible. Therefore, assessing the radiation tolerance of electronic systems used in fusion reactors is of paramount importance. To validate the radiation resistance of front-end electronics and cable in various diagnostic systems, a test circuit board was designed. This board integrates a variety of commonly used amplification chips and power supply chips to assess their performance in the environment of a fusion reactor. The experiment selected three different types of cables commonly used in fusion reactors for separate testing, to assess their parameter changes before and after irradiation experiments. Gamma Irradiation Experiments were conducted using a cobalt-60 (Co-60) radiation source at the Irradiation Center of Nanjing University of Aeronautics and Astronautics. The test circuit board was exposed to continuous gamma irradiation at two test points, with dose rates of 6 Gy/min and 1 Gy/min, respectively, for a total of 6.5 h, Data from the irradiation experiments were collected and analyzed. The results show that under continuous gamma irradiation, CJ7805 and AMS1117–5 chips stopped working at 586 Gy and 776 Gy, respectively. The output of the LT1175I5 chip dropped from -5 V to -1 V at 447 Gy. Apart from the radiation-resistant power supply chips, the output of other power supply chips slightly decreased. The signal reference of the charge amplifier dropped at 741 Gy but then slowly rose again, and the signal amplitude decreased at 900 Gy. The signal reference of the current amplification circuit remained unchanged, with a slight decrease in amplitude. The signal reference of the voltage amplifier exhibited jitter, with no change in amplitude. The experiment provides valuable data support for the radiation-resistant design of electronic systems in the environment of a nuclear fusion reactor. [ABSTRACT FROM AUTHOR]

• The inert tungsten carbides are activated by C-etching in the presence of Pt. • Pt–WC with C-defects shows efficient activity for cleavage of aryl ether C O bond. • The catalytic promotion is ascribed to the synergy effects of Pt species and C-defects. • Pt–WC displays a different reaction pathway compared with WC and Pt alone. • The synergy effects of other transition metals and C-defects are also manifested. Transition-metal carbides are attractive heterogeneous catalysts for the transformation of lignin-derived compounds. However, the effects of the surface carbon defect (C-defect) remain unclear due to coke deposition and exposed C terminations. Herein, we transform inert tungsten carbides (WC) into active catalysts via surficial C-etching using transition metals in the presence of H 2. An optimized 1% Pt–WC catalyst with synergy of Pt and C-defects can perform a 78.6% conversion in the selective hydrogenolysis of guaiacol to phenol with 89.0% selectivity at 300 °C, while the intact WC only gives a 7.1% guaiacol conversion with 51.0% phenol selectivity under the same conditions. As a result, the 1% Pt–WC catalyst exhibits 19-fold higher reaction rate and 12.6-fold higher turnover frequency than those of WC. Moreover, no substantial loss of catalytic performance has been observed with 1% Pt–WC for 50 h on stream. A rational reaction pathway is accordingly proposed through in-depth characterizations. [ABSTRACT FROM AUTHOR]

Most of multi-component high entropy alloys (HEAs) are only based on metal elements and rarely added with nonmetallic elements. In present paper, CoCrFeNiMn HEA added with 0.1 at.% N has been successfully synthesized by mechanical alloying (MA) followed by vacuum hot pressing sintering (VHPS). During the MA process, the alloying elements were gradually alloyed and formed as face-center (FCC) solid solutions. Subsequently, σ phases, Cr 2 N phases, FCC matrix phases with traces of Cr 23 C 6 carbides were observed after VHPS. In comparison with CoCrFeNiMn HEA produced by the same method, the Vickers hardness increased up to 468HV, while the yield stress, ultimate compressive strength increased by 203 MPa and 115 MPa respectively, accompanied by a small decrease in plasticity. This demonstrates that adding N element is a viable approach for properties enhancement of HEAs. [ABSTRACT FROM AUTHOR]

• LaCo 1- x Mn x O 3 perovskites with different substitutions of Co by Mn are prepared. • Substitution of Mn promotes Co 2 C formation and elevates Co 2 C/Co0 ratio. • TPR-MS and XPS are employed to quantitatively define the Co 2 C content. • The yield of alcohols can be attributed to the dual sites of Co0–Co 2 C. LaCo 1- x Mn x O 3 perovskites with different substitutions of Co by Mn were investigated as precursors of catalysts for the CO hydrogenation to produce higher alcohols. Characterization of LaCo 1- x Mn x O 3 perovskites revealed modifications in their structure with the incorporation of Mn into the perovskite lattice affected the structure of the catalysts by reduction prior the reaction. The presence of Mn facilitated the production of alcohols and suppressed the formation of undesirable products, i.e., methane and methanol. Quantitative analysis showed that the catalysts derived from Mn-containing perovskites favored the formation of Co 2 C under the reaction conditions. Thereby the enhanced alcohol selectivity could be explained by the increment of Co 2 C/Co0 ratio. The results demonstrate that the catalysts originated from LaCo 1- x Mn x O 3 perovskites are stable and effective for the synthesis of alcohols by CO hydrogenation. [ABSTRACT FROM AUTHOR]