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This paper introduces a novel approach for parameter sensitivity evaluation and efficient slope reliability analysis based on quantile-based first-order second-moment method (QFOSM). The core principles of the QFOSM are elucidated geometrically from the perspective of expanding ellipsoids. Based on this geometric interpretation, the QFOSM is further extended to estimate sensitivity indices and assess the significance of various uncertain parameters involved in the slope system. The proposed method has the advantage of computational simplicity, akin to the conventional first-order second-moment method (FOSM), while providing estimation accuracy close to that of the first-order reliability method (FORM). Its performance is demonstrated with a numerical example and three slope examples. The results show that the proposed method can efficiently estimate the slope reliability and simultaneously evaluate the sensitivity of the uncertain parameters. The proposed method does not involve complex optimization or iteration required by the FORM. It can provide a valuable complement to the existing approximate reliability analysis methods, offering rapid sensitivity evaluation and slope reliability analysis.

Objective In order to reduce surgical scars and the risk of neurovascular injury for the treatment of terrible triad injuries of the elbow (TTI), minimally invasive and better therapeutic effect approaches are being explored to replace the conventional combined lateral and medial approach (CLMA). This study was performed to compare the clinical effect and security of the modified posterior approach (MPA) through the space of the proximal radioulnar joint vs the CLMA for treatment of TTI. Methods This study retrospectively analyzed 76 patients treated for TTI from January 2009 to December 2020 (MPA: n = 44; CLMA: n = 32). Treatment involved plate and screw fixation or Steinmann pin fixation for the radial head and ulnar coronoid process fractures. Surgeons only sutured the lateral ligament because the medial collateral ligament was usually integrated in the TTI. The continuous variables were compared by the independent Student t‐test and the categorical variables by the χ2‐test or Fisher's exact test. Results Both groups of patients attained a satisfactory MEPS after the operation. The MEPS (MPA: 96.82 ± 6.04 vs CLMA: 96.56 ± 5.51) was not significantly different between the two groups (p > 0.05). However, the MPA resulted in better elbow flexion and extension (MPA: 123.98 ± 10.09 vs CLMA: 117.66 ± 8.29), better forearm rotation function (MPA: 173.41 ± 6.81 vs CLMA: 120.00 ± 12.18), and less intraoperative hemoglobin (MPA: 9.34 ± 5.64 vs CLMA: 16.5 ± 8.75) and red cell volume loss (MPA: 3.09 ± 2.20 vs CLMA: 6.70 ± 2.97) (All p

Qualitatively identifying the dominant catalytic site for each step of a semi-continuous reaction and semi-quantitatively correlating such different sites to the catalytic performance is of great significance toward the integration of multiple well-optimized sites on a heterogeneous catalyst. Herein, a series of structurally defined TiOx-based catalysts were synthesized to provide a feasible approach to investigate the aforementioned issues using the semi-continuous oxidation of glycerol as a model reaction. Detailed investigations have verified the simultaneous presence of two kinds of Pt active sites: 1) Negatively charged Pt bound to the oxygen vacancies of modified TiOx in the form of Ptδ−-Ov-Ti3+ sites and 2) metallic Pt (Pt0 site) located away from the interface. Meanwhile, the proportion of surficial and interfacial sites varies over this series of catalysts. Combined in situ FTIR experiments revealed that the reaction network was well-tuned via a site cooperation mechanism: The surficial Pt0 sites dissociatively adsorb the OH group of glycerol with a monodentate bonding geometry and the Ptδ−-Ov-Ti3+ sites dissociate the C=O bond of the aldehyde group in a bidentate form. Furthermore, CO-FTIR spectroscopy confirmed a correlation between the reaction rate/product selectivity and the fraction of surficial/interfacial sites. A rational proportion of surficial and interfacial sites is key to enabling a high yield of glyceric acid. The most active catalyst with 32% surface sites and 68% interfacial sites exhibited 90.0% glycerol conversion and 68.5% GLYA selectivity. These findings provide a deeper understanding of the structure-activity relationships using qualitative identification and semi-quantitative analysis.

It is of great importance to develop a spherical γ-alumina support with high hydrothermal stability to be used in platinum reforming catalyst processes. The porous pseudo-boehmite powder with a high surface area was first synthesized via a simple separate nucleation and aging steps method, and was then used as a precursor to produce a spherical γ-Al2O3 support via an oil–ammonia column method. The as-synthesized pseudo-boehmite has a substantially greater specific surface area of 336.0 m2·g−1 in comparison with the commercial Sasol boehmite powder (293.0 m2·g−1) from Sasol Chemicals. In addition, the as-prepared spherical γ-Al2O3 support derived from the as-synthesized pseudo-boehmite also possesses a higher specific surface area of 280.0 m2·g−1 compared to the corresponding Sasol sample. Moreover, the as-prepared spherical γ-Al2O3 balls demonstrate a much higher specific surface area of 185.0 m2·g−1 compared with the Sasol sample of 142.0 m2·g−1 after hydrothermal tests at 600 °C, suggesting its promising application in the chemical industry.

An elegant and efficient approach consisting in the co-intercalation of stabilizing molecular anions is described here. The thermal stabilizer calcium diethyl bis[[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphonate] (Irganox 1425, MP-Ca) and a photo-oxidation stabilizer (hindered amine light stabilizer, HALS) are co-intercalated into the interlayer regions of layered double hydroxides (LDH) in a one-step coprecipitation. These hybrid organic–inorganic materials are successively dispersed in polypropylene to form HnMn′-Ca2Al/PP composite films (with H = HALS and M = MP) through a solvent casting method. The corresponding crystalline structure, chemical composition, morphology as well as the resistance against thermal aging and photo-oxidation are carefully investigated by various techniques. The results show that the powdered HnMn′-Ca2Al-LDHs hybrid materials have a much higher thermal stability than MP-Ca and HALS before intercalation. In addition, the HnMn′-Ca2Al/PP composites exhibit a higher overall resistance against thermal degradation and photo-oxidation compared to LDHs intercalated with only HALS or MP. This underlines the benefit of the co-intercalation. The co-intercalated LDH materials pave a new way in designing and fabricating high-performance multifunctional additives for polymers.

It is of great interest and importance to resource utilization of waste biomass to produce porous carbon for environmental treatments. Pore structure and properties of the obtained carbon mainly relate to carbonization conditions and biomass types. In this work, a series of porous, biomass-activated carbons (AC) were prepared using shaddock peel, with ZnCl2 as a pore-forming agent. The effect of carbonization temperature and the mass ratio between ZnCl2 and shaddock peel were thoroughly investigated. The material composition, surface chemical properties, and surface structures of samples were carefully characterized. The specific surface area and adsorption capacity to methylene blue (MB) of adsorbents were changed with the carbonization temperature and the mass ratios between ZnCl2 and shaddock peel; when the temperature was at 1000 °C and the mass ratio was equal to 2:1, the resulting adsorbent had the largest specific surface area of 2398.74 m2/g and average pore size of 3.04 nm, which showed the highest adsorption capacity to MB to be 869.57 mg/g. The adsorption processes of biomass AC adsorbent matched the pseudo-second-order kinetic model and Langmuir isotherm model. This efficient and environmentally friendly biomass AC adsorbent from shaddock peel, activated by ZnCl2, is a promising candidate for the treatment of water pollution.

It is of increasing interest and an important challenge to develop highly efficient less-expensive cathode catalysts for anion-exchange membrane fuel cells (AEMFCs). In this work, we have directly prepared a carbon-supported CoS nanocatalyst in a solvothermal route and investigated the effect of heat-treatment on electrocatalytic activity and long-term stability using rotating ring-disk electrode (RRDE). The results show that the heat-treatment below 400 °C under nitrogen atmosphere significantly enhanced the electrocatalytic performance of CoS catalyst as a function of annealed temperature in terms of the cathodic current density, the half-wave potential, the HO2− product and the number of electrons transferred. The CoS catalyst that annealed at 400 °C (CoS-400) has exhibited a promising performance with the half-wave potential of 0.71 V vs. RHE (the highest one for non-precious metal chalcogenides), the minimum HO2− product of 4.3% at 0.60 V vs. RHE and close to the 4-electron pathway during the oxygen reduction reaction in 0.1 M KOH. Also, the CoS-400 catalyst has comparable durability to the Pt/C catalyst.

Magnesium silicate as a high-performance adsorption material has attracted increasing attention for the removal of organic dye pollution. Here, we prepared a series of magnesium silicate hydrates (MSH) in a hydrothermal route, and carefully investigated the corresponding adsorption behavior towards methylene blue (MB) as well as the effect of surface charge on adsorption capacity. The results show that surface charge plays a key role in the adsorption performance of MSH for MB, a negative surface charge density follows the increase of Si/Mg feeding ratio from 1.00 to 1.75, and furthermore the higher negative charge favors the improvement of the adsorption capacity. Among four investigated samples (MSH = 1.00, 1.25, 1.50, and 1.75), MSH-1.75 has the highest negative surface charge and shows the largest adsorption capacity for MB. For example, the equilibrium adsorption quantity is 307 mg·g−1 for MSH-1.75, which is 35% higher than that of 227 mg·g−1 for MSH-1.00. Besides, for MSH-1.75, the as-prepared sample with negative charge exhibits ca. 36% higher adsorption quantity compared to the sample at the zero point of charge (pHZPC). Furthermore, magnesium silicate hydrate material with Si/Mg feeding ratio = 1.75 demonstrates the promising removal efficiency of beyond 98% for methylene blue in 10 min, and the maximum adsorption capacity of 374 mg·g−1 calculated from the Langmuir isotherm model.