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Direct non-oxidative methane coupling (NMC) is one of the promising pathways for methane upgrading into value-added olefin and aromatic hydrocarbons. The silica-supported iron (i.e., Fe/SiO 2) catalyst has been reported effective for NMC, but the effects of silica support on the catalyst property and NMC performance have rarely been explored. In this work, we prepared a vitreous silica-supported iron (Fe/SiO 2 -V) catalyst by flame fusion of a mixture of quartz silica and fayalite. The physicochemical properties and NMC performance of the as-prepared catalysts were measured. Compared to crystalline cristobalite support in Fe/SiO 2 catalyst that has been studied previously, vitreous silica support has disordered Si-O bonds and structural defects, enabling better iron dispersion and more vital metal-support interaction. The as-prepared Fe/SiO 2 -V catalyst had a shorter induction period in methane activation and lower coke yield in NMC. The increase in iron concentration in Fe/SiO 2 -V catalysts elongated the catalyst induction period and promoted aromatics and coke formation. The coke type of the spent Fe/SiO 2 -V catalyst is more uniform than the cristobalite-supported iron catalyst. [Display omitted] • Vitreous silica-supported iron catalysts were prepared by an oxyhydrogen flame fusion method. • The amorphous vitreous silica support contains disordered and defective Si-O bonds. • Iron has higher dispersion and more uniform bonding in the vitreous silica support. • Vitreous silica-supported iron enabled fast methane activation and low coking in NMC. • Increase in iron loading in vitreous silica support promoted aromatics formation. [ABSTRACT FROM AUTHOR]

Background and Objective: Carpal tunnel syndrome (CTS) is the most common type of median nerve entrapment neuropathy. This study aims to comparatively assess the effectiveness and clinical efficacy of modified transforaminal endoscopic minimally invasive incision of transverse carpal ligament against traditional open incision of transverse carpal ligament in the treatment of CTS. Method: The clinical data of 35 patients (57 wrists) with primary CTS treated in Shanxi Bethune Hospital, China, were retrospectively analyzed. The patients were divided into observation group (21 cases, 33 wrists) and control group (14 cases, 24 wrists), respectively, who underwent modified endoscopic minimally invasive incision of transverse carpal ligament and traditional open incision of transverse carpal ligament release. The Boston Carpal Tunnel Questionnaire (BCTQ) was assessed at for points: before the operation; 2 weeks; 1 month; and 3 months after operation. The BCTQ scores of the two groups were compared on all four points. The incidence of intraoperative and postoperative complication was used as the evaluation index. The study variables were comparatively assessed before and postoperation and also between the groups. Results: The BCTQ scores at 2 weeks, 1 month and 3 months after the operation were significantly lower than preoperative BCTQ scores (P < 0.005) for both the groups. There was no significant difference in BCTQ scores between the two groups at the four assessment points (P > 0.005). The scar size and wound healing time were significantly better with modified transforaminal endoscopic minimally invasive transverse carpal ligament incision. Conclusion: The clinical effects of both modified transforaminal minimally invasive incision of transverse carpal ligament and traditional open incision of transverse carpal ligament are significant, while the treatment efficacy of modified transforaminal minimally invasive transverse carpal ligament incision is better in terms of operation time, wound size, postoperative scar size and incision healing time. [ABSTRACT FROM AUTHOR]

Purpose: Several recent studies have reported a possible association between gut microbiota and intervertebral disc degeneration; however, no studies have shown a causal relationship between gut microbiota and disc degeneration. This study was dedicated to investigate the causal relationship between the gut microbiota and intervertebral disc degeneration and the presence of potentially bacterial traits using two-sample Mendelian randomization. Methods: A two-sample Mendelian randomization study was performed using the summary statistics of the gut microbiota from the largest available genome-wide association study meta-analysis conducted by the MiBioGen consortium. Summary statistics of intervertebral disc degeneration were obtained from the FinnGen consortium R8 release data. Five basic methods and MR-PRESSO were used to examine causal associations. The results of the study were used to examine the causal association between gut microbiota and intervertebral disc degeneration. Cochran's Q statistics were used to quantify the heterogeneity of instrumental variables. Results: By using Mendelian randomization analysis, 10 bacterial traits potentially associated with intervertebral disc degeneration were identified: genus Eubacterium coprostanoligenes group, genus Lachnoclostridium, unknown genus id.2755, genus Marvinbryantia, genus Ruminococcaceae UCG003, family Rhodospirillaceae, unknown genus id.959, order Rhodospirillales, genus Lachnospiraceae NK4A136 grou, genus Eubacterium brachy group. Conclusion: This Mendelian Randomization study found a causal effect between 10 gut microbiota and intervertebral disc degeneration, and we summarize the possible mechanisms of action in the context of existing studies. However, additional research is essential to fully understand the contribution of genetic factors to the dynamics of gut microbiota and its impact on disc degeneration. [ABSTRACT FROM AUTHOR]

Direct nonoxidative methane conversion (DNMC) transforms CH4 to higher (C2+) hydrocarbons and H2 in a single step, but its utility is challenged by low CH4 equilibrium conversion, carbon deposition (coking), and its endothermic reaction energy requirement. This work reports a heat‐exchanged autothermal H2‐permeable tubular membrane reactor composed of a thin mixed ionic‐electronic conducting SrCe0.7Zr0.2Eu0.1O3–δ membrane supported on a porous SrCe0.8Zr0.2O3–δ tube in which a Fe/SiO2 DNMC catalyst is packed, that concurrently tackles all of these challenges. The H2‐permeation flux drives CH4 conversion. O2 from an air simulant (O2/He mixture) sweep outside the membrane reacts with permeated H2 to provide heat for the endothermic DNMC reaction. The energy balance between the endothermic DNMC and exothermic H2 combustion on opposite sides of the membrane is achieved, demonstrating the feasibility for autothermal operation using a simple air sweep gas. Moreover, the back diffusion of O2 from the sweep side to the catalyst side oxidizes any deposited carbon into CO. Thus, for the first time demonstrating all the desired attributes, a heat‐exchanged H2‐permeable membrane reactor capable of achieving single‐step auto‐thermal DNMC catalysis while simultaneously improving CH4 conversion and preventing coking is achieved. [ABSTRACT FROM AUTHOR]

The accurate prediction and assessment of effluent quality in wastewater treatment plants (WWTPs) are paramount for the efficacy of sewage treatment processes. Neural network models have exhibited promise in enhancing prediction accuracy by simulating and analyzing diverse influent parameters. In this study, a back propagation neural network hybrid model based on a tent chaotic map and sparrow search algorithm (Tent_BP_SSA) was developed to predict the effluent quality of sewage treatment processes. The prediction performance of the propose hybrid model was compared with traditional neural network models using five performance indicators (MAE, RMSE, SSE, MAPE and R2). Specifically, in comparison with the prior Tent_BP_SSA, Tent_BP_SSA2 demonstrated notable enhancements, with the R2 increasing from 0.9512 to 0.9672, while MAE, RMSE, SSE, and MAPE decreased by 9.62%, 18.84%, 24.80%, and 47.10%, respectively. These indicators collectively affirm that the utilization of higher-order input parameters ensures improved accuracy of the Tent_BP_SSA2 hybrid model in predicting effluent quality. Moreover, the Tent_BP_SSA2 model exhibited robust prediction ability (R2 of 0.9246) when applied to assess the effluent quality of an actual sewage treatment plant. The incorporation of integrated models comprising the sparrow search optimizing algorithm, tent chaotic mapping, and higher-order magnitude decomposition of input parameters has demonstrated the capacity to enhance the accuracy of effluent quality prediction. This study illuminates novel perspectives on the prediction of effluent quality and the assessment of effluent warnings in WWTPs. [Display omitted] • The developed hybrid neural network model consisted of chaotic mapping and a sparrow search algorithm. • High order of magnitude input parameters and hybrid models demonstrated better predictive power. • The hybrid model was verified using Benchmark Simulation Model 1 and at an actual sewage treatment plant. • Accurate prediction of the effluent quality of the actual sewage treatment plant was obtained using the hybrid model. [ABSTRACT FROM AUTHOR]

Hierarchical two-dimensional (2D) lamellar zeolites represent a young emerging field and a novel expression of the zeolite frameworks. Accompanied with synthesis and catalytic performance investigation, assessment on the local environment and catalytic behavior of acid sites in 2D zeolites are needed. Here, we described the local environment of Lewis acid sites and evaluated catalytic activities of external acid sites (i.e. sites on external surface and in mesopores) in 2D lamellar titanium silicalite-1 (TS-1) zeolites. For comparison purpose, four TS-1 zeolites, including 3D TS-1, multilamellar 2D TS-1 without pillarization and with pillarization by silica and silica/titania, respectively, were prepared. The local environment of Ti-sites, including coordination status of Ti-atom, speciation of hydroxyl (-OH) group that hints degree of confinement, acid site strength and accessibility, was collectively assessed by spectroscopic and organic base titration measurements. Kinetic studies of cyclooctene (C 8 H 14) epoxidation with hydrogen peroxide (H 2 O 2) discerned catalytic activity of external Ti-sites that decreased with increasing mesoporosity due to decrease in site confinement. Image 1 • External Lewis acid sites in 2D TS-1 zeolites were quantified. • 2D TS-1 zeolites have high density of isolated surface silanol and titanol groups. • Reactivity of external sites decreases with increasing mesoporosity in 2D TS-1. • Decrease in reactivity of external sites is caused by loss of partial confinement. • Kinetic decoupling of epoxidation pathways enabled catalytic behavior assessment. [ABSTRACT FROM AUTHOR]

Lamellar MFI zeolite and lamellar MFI zeolite supported nickel were synthesized and examined for ex-situ catalytic upgrading of the vapors (without using any fluidized gases such as N 2 and H 2) resulted from fast pyrolysis of wood chips in comparison to its commercial MFI zeolite and its supported nickel counterparts. Pyrolysis tests were carried out using a catalytic augur reactor at atmospheric pressure, while pyrolysis unit was operating at 450 °C and upgrading unit at 420 °C, respectively. The introduction of nickel with a high dispersion over the zeolitic supports caused a significant increase in the products of aromatic compounds. Moreover, the addition of nickel to zeolite supports changed their acidity and decreased the total number of acid sites and the ratio of Brønsted to Lewis acid sites as determined by pyridine-FTIR spectroscopy. The use of lamellar zeolite catalysts increased the efficiency of catalytic cracking of pyrolysis vapors and their modification with nickel helped tuning the Lewis acidity to further increase catalytic cracking which resulted in a higher yield of the low molecular weight aromatics present in the bio-oil. • Lamellar catalysts are synthesized and extensively characterized. • Ex-situ catalytic fast pyrolysis without fluidizing gas can lead to a low bio-oil deoxygenation. • Lamellar catalysts are found to enhance catalytic cracking of pyrolysis oil vapors. • Lamellar catalysts show no loss in activity after multiple uses. [ABSTRACT FROM AUTHOR]

[Display omitted] • Developed detailed surface reaction mechanism for methane non-oxidative coupling. • Elucidated the interplay between catalytic and gas-phase chemistry. • Demonstrated catalytic generation of ethylene during methane coupling. • Showcased enhanced selectivity to ethylene by minimizing gas-phase reactions. Non-oxidative conversion of methane over iron atoms on silica can provide a potential catalytic route to directly produce ethylene. However, its mechanism remains elusive. Herein, we perform multiscale simulations to elucidate the key pathways and provide insights into how to tune this process. Extensive density functional theory calculations are conducted for the surface reactions, which are coupled to nearly 10,000 gas-phase reactions. The entire model is assessed with new experimental data. Ab initio phase behavior indicates that iron atoms form isolated carbides under reaction conditions. Unlike decades of prior hypothesis for CH 3 radical desorbing from the catalyst and recombining to form ethane in the gas-phase as the sole C 2 formation mechanism, ethylene is predominantly produced on the catalyst and is consumed by gas-phase reactions to acetylene and aromatics. Highest ethylene selectivity with high methane one-pass conversion can be achieved by eliminating gas-phase reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Developed detailed surface reaction mechanism for methane non-oxidative coupling. • Elucidated the interplay between catalytic and gas-phase chemistry. • Demonstrated catalytic generation of ethylene during methane coupling. • Showcased enhanced selectivity to ethylene by minimizing gas-phase reactions. Non-oxidative conversion of methane over iron atoms on silica can provide a potential catalytic route to directly produce ethylene. However, its mechanism remains elusive. Herein, we perform multiscale simulations to elucidate the key pathways and provide insights into how to tune this process. Extensive density functional theory calculations are conducted for the surface reactions, which are coupled to nearly 10,000 gas-phase reactions. The entire model is assessed with new experimental data. Ab initio phase behavior indicates that iron atoms form isolated carbides under reaction conditions. Unlike decades of prior hypothesis for CH 3 radical desorbing from the catalyst and recombining to form ethane in the gas-phase as the sole C 2 formation mechanism, ethylene is predominantly produced on the catalyst and is consumed by gas-phase reactions to acetylene and aromatics. Highest ethylene selectivity with high methane one-pass conversion can be achieved by eliminating gas-phase reactions. [ABSTRACT FROM AUTHOR]

• Catalytic performance of metal (Ga or Zn)-loaded mesoporous lamellar zeolites was evaluated. • Mesoporous lamellar structure is pivotal in determining metal dispersion in zeolite catalyst. • Metal loading changes the acidity of the zeolite catalyst and effect of Zn is more pronounced compared to Ga. • Higher liquid aromatics yield and selectivity for mono-benzene alkylated aromatics was observed while less coke was formed. • Both zeolite structure (mesoporosity) and type of metal dopant affect the catalytic performance of catalyst. The effects of meso-/microporous structure and metal-modification with gallium or zinc on catalytic performances of lamellar MFI zeolites in ethylene conversion reaction to liquid aromatics were investigated. TEM, XRD, Ar adsorption-desorption, UV-Visible spectroscopy, and H 2 -TPR measurements showed that the zeolite structure is a pivotal factor for controlling the type of metal dopant species forming on zeolite, their size, and their distribution. Adding metal dopants to zeolite structure decreased the Brønsted to Lewis (B/L) acid site ratio in the zeolites and improved their catalytic performance. As a result, metal-modified lamellar MFI zeolites showed higher liquid aromatics yield and selectivity for mono-benzene alkylated aromatics and lower coke formation rate compared to their microporous commercial MFI analogies. Zinc-loaded lamellar MFI had the most efficient catalytic performance among all studied catalysts. This phenomenon can be explained by higher accessibility of reactants to active sites and facilitated transport of products from lamellar structure of this zeolite and the low B/L acid site ratio of this catalyst provided by metal-modification, which is more suitable for ethylene aromatization. A bifunctional reaction mechanism has been proposed based on the analysis results of reaction product distributions that demonstrates the effect of both zeolite acid sites and metal sites in conversion of ethylene to liquid aromatics over MFI zeolite catalysts. [ABSTRACT FROM AUTHOR]