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[Display omitted] • A novel kinetic modeling strategy combining the moments method with an improved multi-objective mayfly algorithm is proposed. • The improved multi-objective mayfly algorithm is proposed. • Industrial-scale propylene polymerization model based on the proposed method is established. • The proposed algorithm presents the state-of-art ability on prediction results of the PR and the MI. • This proposed algorithm has a good prospect for the PP industrial application. Polypropylene (PP) is a synthetic resin with exceptional physical and chemical properties, making it suitable for various household and industrial applications. However, as the demand for PP continues to rise, the polypropylene industry faces challenges in improving its quality and efficiency. Developing an accurate mathematical model that describes the continuous polymerization process is crucial for enhancing PP production, as it is useful for controlling product quality and improving production efficiency. While previous studies have focused on modeling propylene polymerization using laboratory-scale and pilot-scale reactors, these models do not effectively apply to industrial-scale processes due to the complexity of the industrial environment. Therefore, a novel kinetic modeling method combining the modeling of the kinetic mechanism of the polymerization reaction with an intelligent optimization algorithm for the industrial-scale continuous gas-phase fluidized bed propylene polymerization process is proposed. To establish the kinetic mechanism model, the improved moments (MOM) method is utilized to derive a set of mass balance equations that account for various fundamental processes such as catalyst activation, chain initiation, chain growth, chain transfer to hydrogen, chain transfer to monomers, chain transfer to co-catalysts, and spontaneous deactivation. However, kinetic parameters serve as the link between the theoretical model and the actual production process, so the kinetic parameters estimation problem need to be transformed into a multi-objective problem by minimizing the least squares difference between the measurement data of the actual industry process and the predicted result of the kinetic model. Therefore, an improved multi-objective mayfly algorithm (IMOMA) is introduced to estimate the polymerization kinetic parameters, which incorporates the simulated binary crossover (SBX) operator and the polynomial mutation (PM) operator into the basic multi-objective mayfly algorithm (MOMA). Finally, by fitting industrial measurement data of the melt index (MI) and the polymerization rate (PR) of an actual polypropylene industrial case study, the proposed algorithm accurately determines the polymerization kinetic parameters. The results demonstrate that the MOM-IMOMA modeling approach outperforms other methods and holds significant promise for industrial-scale polypropylene production. [ABSTRACT FROM AUTHOR]

[Display omitted] • A SiOC@carbon ceramic spring with the laminar spring-like structure was fabricated. • The ceramic spring exhibits excellent superelasticity and oxidation resistance. • The derived sensor can function at a wide temperature range from −196 °C to 500 °C. • The sensor has superior physiological signal and human movement capture capability. With the flourishing development in space exploration and human motion detection, the wide-temperature flexible pressure sensors are urgently required in various complex application situations. One massive challenge of current available sensors is to enhance the oxidation resistance property, which is crucial for their applications in high-temperature environments. Herein, we fabricated a superelastic silicon oxycarbide @carbon (SiOC@C) ceramic spring, possessing a porous lamellar and spring-like structure. The spring-like structure tends to deform and absorb the energy under the external loads, and then the anisotropic lamellar structure can effectively and uniformly release the stress. The as-prepared SiOC@C spring exhibits excellent superelasticity, high compressibility (60%), and robustness (∼99.0% maximum stress retention after 1000 cycles at 50% compression). Meanwhile, the SiOC@C spring-derived sensor possesses a high sensitivity under low pressure (282.46 kPa−1 at < 1.3 kPa), a low detection limit (< 0.098 Pa) and a short response/recovery time (∼12 ms/4 ms). Moreover, benefiting from the high/low-temperature resistance of SiOC nanolayer coated on the carbon framework, the SiOC@C spring-based sensor can function properly at a wide temperature range from − 196 °C to 500 °C, showing the potential application in various fields of biomedical monitoring, space exploration, and automotive industries. [ABSTRACT FROM AUTHOR]

An integrated isoelectric precipitation (IP) – ultrafiltration (UF) – nanofiltration (NF) – lactic acid (LA) fermentation process was established for recovering water, proteins, cells and LA from model dairy wastewater (MDW). This process could solve the problems of sludge/retentate disposal and membrane fouling during membrane-based wastewater treatment. The IP process greatly retarded concentration polarization and fouling of UF. However, PES membrane was still severely fouled by whey proteins. XPS results showed that carboxyl groups (C O) belonging to the proteins was on PES10 surface, but it was not found on Ultracel PLGC membrane. Proteins in MDW with IP were completely retained by Ultracel PLGC UF membrane and lactose almost passed through. After IP-UF pretreatment, the fouling of NF membrane was greatly retarded (irreversible fouling decreased from 44.4% to 11.1% in a pilot-plant test). Thus, the volume reduction ratio was highly increased to 37 and the retentate with high strength lactose of 44.2 g L −1 was obtained. With a model NF retentate (45.0 g L −1 of lactose) without proteins, 5.42 g L −1 of cell mass and 37.6 g L −1 of LA concentration were produced by the LA producer B. coagulans IPE22. [ABSTRACT FROM AUTHOR]

A novel integrated isoelectric precipitation–nanofiltration (NF)–anaerobic fermentation process was proposed for fully recycling model dairy wastewater (MDW). Isoelectric precipitation at pH 4.80 and subsequent centrifugation could remove most proteins. Acetic and butyric acids from anaerobic fermentation were available for acidic precipitation, and the performance was comparable to that of hydrochloric acid. The pretreatment of MDW by precipitation could greatly retard NF membrane fouling, especially at pH 7.09 owing to the electrostatic repulsion between solutes and membrane. NF270 membrane was preferred for MDW concentration due to its high antifouling performance, high permeability and acceptable permeate quality. Anaerobic fermentation fed with model NF retentate without caseins produced higher proportion of acetate, butyrate and hydrogen, and this effluent with shorter-chain volatile fatty acids (VFAs) and lower pH was more suitable for casein precipitation in dairy wastewater. [ABSTRACT FROM AUTHOR]

• We prepared Bi 2 Se 3−x O x by incorporating oxygen into bismuth selenide lattice. • The incorporated oxygen boosted significantly the charge separation. • The partial reservation of selenium contributed to the adsorption capability. • We can simultaneous use adsorption and catalysis capabilities of the catalyst. Rational utilization of both adsorption and catalysis capabilities is an intriguing prospect in environmental remediation. Here, we demonstrate the tunability of these two capabilities in the case of bismuth selenide upon post-calcination. The temperature-related concentration of oxygen impurities in bismuth selenide gives a positive effect regarding charge separation. Meanwhile, the partial reservation of selenium is beneficial for the adsorption on antibiotics. Experimental results show that the bismuth selenide nanosheets calcinated under 180 °C exhibit the best photocatalytic performance, where the charge separation and adsorption reach an optimal equilibrium. The photocatalytic degradation efficiency reached over 90% within 120 min under simulated sunlight irradiation. The findings of this study highlight the regulation of adsorption and catalysis in environmental remediation, as well as providing new pathways to develop versatile nanomaterials for other environmental applications. [ABSTRACT FROM AUTHOR]

Three-dimensional gas–solid flow in a dual-column slot-rectangular spouted bed (DSRSB) with a suspended partition was studied experimentally and numerically. Predictions from the coupled computational fluid dynamics and discrete element method (CFD–DEM) were compared with experimental measurements based on pressure transducers and an optical fibre probe. The suspended partition position had little effect on particle velocity and voidage under stable spouting conditions. The predicted total pressure drops were in reasonable agreement with experimental values. For steady spouting, particle velocity and bed voidage were strongly influenced by static bed height. Solids exchange between the two chambers was modelled. The solids exchange rate decreased slightly with time as predicted by the DEM model. Raising the suspended partition facilitated solids exchange between the chambers. Measured profiles of pressure, voidage and particle velocity were in good agreement with simulation predictions, demonstrating the capability of the numerical model for predicting such flows. [ABSTRACT FROM AUTHOR]

[Display omitted] • Vertically aligned TiO 2 nanorods were synthesized directly on the surface of microfibers by in-situ growth. • A novel 'fiber/nanorod/aerogel' composite was constructed for thermal insulators. • The composite with low thermal conductivity exhibited significantly enhanced infrared radiation shielding. • In-situ growth of TiO 2 nanorods reduced the gaseous conductivity by increasing the interfacial adhesion force. Fiber/aerogel composites attract considerable interest as thermal insulation materials due to their low thermal conductivity. However, in practice they deliver unsatisfactory performance due to their high infrared radiation transmittance and poor interfacial adhesion. Herein, we report a simple strategy for constructing vertically aligned 1D rutile TiO 2 nanorod arrays (TiO 2 -NRAs) directly on the surface of quartz fibers (QFs) by in-situ growth. A novel 'fiber/nanorod/aerogel' composite was synthesized by filling the pores of QF/TiO 2 -NRAs with SiO 2 -Al 2 O 3 aerogels (ASAs) through vacuum impregnation. The QF/TiO 2 -NRAs/ASA composite exhibited excellent thermal insulation (0.071 W·m−1·K−1 at 1100 °C), infrared radiation shielding performance (an extinction coefficient greater than 150 cm−1 and an infrared reflectivity greater than 95%), fire resistance (more than 1200 °C), and compressive strength (0.37 MPa, 10% strain). In-situ growth of TiO 2 -NRAs can reduce the gaseous thermal conductivity by increasing the interfacial adhesion force between fibers and aerogels, and reduce the radiation heat transfer by shielding infrared radiation. This strategy is applicable to multi-type fibers reinforced silica-based aerogel materials used for insulation and protection in extreme environments. [ABSTRACT FROM AUTHOR]