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To take better advantage of buckwheat polyphenols, processings including extrusion, steam explosion, microwave, roasting, superheated steam, ultrasound and enzymolysis treatment were applied to buckwheat bran to release more bioactive polyphenols. Polyphenols were extracted and characterized, and rutin was identified as the predominant compound. To further improve the properties of buckwheat polyphenols, rutin was selected as the target polyphenol and a formation of its ionic cross-linking complex was proposed. Rutin was loaded on chitooligosaccharide as Rutin-COS with tripolyphosphate (TPP) as crosslinking agent, whose molecular structure and properties were investigated. Results showed that all processing significantly increased (p < 0.05) the content of buckwheat polyphenols, up to 1.83-fold increase. The composition of polyphenols was altered, and their antioxidant (up to 15% increase) and antibacterial activities were significantly enhanced (p < 0.05). Among all the processings, extrusion and superheated steam showed the best effect. For Rutin-COS complex, the encapsulation efficiency was as high as 74.77% with the mass ratio of rutin and COS at 1:8. The structure of Rutin-COS was stabilized by hydrogen bonding between aromatic rings of rutin and amino and hydroxy groups of COS in the network formed by COS and TPP. Compared to free rutin, Rutin-COS presented better thermal stability and water solubility. The antioxidant and antibacterial activities of Rutin-COS were also significantly improved (p < 0.05) due to the molecular interaction between rutin and COS. The combination of processing and complexation strategy for buckwheat polyphenols in this work provided new approaches to take better advantages of polyphenols of cereal foods. [ABSTRACT FROM AUTHOR]

Industrial solid waste red mud discharge has caused serious environmental problems. This study utilized red mud as an additive to loessial silt being used for roadway subgrade material. In this study, unconfined compressive test, direct shear test, electrical resistivity test, and hydraulic conductivity test were conducted on red mud stabilized loessial silt (RMLS) with different red mud dosage (DR) to investigate DR effect on mechanical-electrical-hydro properties. Scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses were carried out to reveal the mechanism from micro perspective. The results showed addition of appropriate amount of red mud (30–42%) effectively improved unconfined compressive strength of treated loessial silt but reduced resistivity and hydraulic conductivity. Significant correlation between resistivity and strength performance of RMLS mixture was developed. Microscopic analysis indicates red mud addition will promote generation of hydration products such as calcium silicate hydrations (C-S-H), calcium silicate aluminates hydrations (C-A-S-H), and ettringite (Aft), which will tightly connect surrounding particles of loessial silt and hydrates. Red mud particles adhere to surface of soil particles and fill in pores between them improving a compact and stable structure. This study demonstrated the feasibility of using red mud as a stabilization material for roadway subgrade and proved that resistivity measurement is a nondestructive testing method to evaluate mechanical properties for RMLS mixture. [ABSTRACT FROM AUTHOR]

To maintain the stable properties of whole Tartary buckwheat and improve its utilization rate, it is crucial to deactivate the lipolytic enzymes. This study assessed the storage and physicochemical properties of Tartary buckwheat bran (TB) after thermal processing, which included roasting, extrusion, and roasting-assisted extrusion for enzyme inactivation. The results showed that the lipase, lipoxygenase (LOX), peroxidase (POD), and catalase (CAT) of TB were effectively inactivated by these thermal processing techniques, particularly by roasting-assisted extrusion. After three months of storage, thermally processed TB maintained low values of fatty acid (FAV), peroxide (POV), and carbonyl (CV). With the water activity of TB decreased by processing, the ability of lipolytic enzymes to access and interact with lipid substrates would also be limited. After undergoing thermal processing, TB exhibited smaller and more dispersed particles. Additionally, the water absorption index (WAI) and water solubility index (WSI) of TB significantly increased, while the pasting viscosities decreased. These changes could alter the action sites of lipolytic enzymes, hinder the sensitivity of lipids towards these enzymes, weaken the enzymatic reaction, ultimately enhancing the storage stability of TB. [Display omitted] • Thermal processing can effectively inactivate the lipase, LOX, POD and CAT of TB. • Decrease in water activity of TB kept lipolytic enzymes activity low during storage. • Processed TB had low and stable FAV, POV and CV during storage. • Thermal processing improved the physiochemical properties of TB. • Roasting-assisted extrusion has the best effect on improving the storage quality of TB. [ABSTRACT FROM AUTHOR]

Multi-layer particle bed has an important application in the field of high temperature filtration. This paper uses the Discrete Element Method to study the flow and segregation characteristics of multi size mixed particles on inclined surfaces. The research results show that: in the process of segregation, the particles mainly carry out rolling motion; when the replacement rate of the particles reaches 60%, the degree of segregation reaches the maximum, and the optimal incline length is 600 mm. A universal quantification index for particle bed segregation and a criterion for the steady state of particle flowing are obtained. The particle size distribution close to continuous distribution is not conducive to particle segregation. The segregation effect of the largest and smallest particles in the mixed particles is better than that of the intermediate particles. This study provides a reference for the design of the segregation layered structure of the multi size particle bed. A universal quantization index for particle segregation was proposed The criterion of steady state and critical replacement rate were given The critical value of slant length for ternary particle segregation was obtained The unique mechanism in the process of segregation of multi-particle size was obtained The multi size particles segregation law based on size distribution was determined [ABSTRACT FROM AUTHOR]

Deep mining will increase the likelihood of coal and gas outburst accidents and do harm to the safety of coal mining. In this study, a coal and gas outburst experiment under deep high‐stress conditions was carried out and stress–gas pressure–temperature response laws in coal and rock surrounding the burst hole were evaluated. The experimental results showed that the stress response around the burst hole was intense and stress variation decreased as distance from the position to burst port increased. The gas pressure in the coal decreased sharply and oscillated several times during the burst process. The maximum rebound range was 0.05 MPa during this process. The decreasing rate of gas pressure reduced with the increase of the position‐burst port distance. The temperature response near the burst port was stronger than peripheral area. The gas internal energy was still the main energy source of coal and gas outbursts, accounting for 75% of the total energy, and played a key role in the burst process. The contribution of elastic potential energy was 22% under deep high‐stress conditions in this study. Based on the analysis of burst energy, the gas and stress were key factors of an outburst. [ABSTRACT FROM AUTHOR]

The catalytic oxidation of VOCs is widely acknowledged as the most available technology to reduce air pollution. Among the catalysts for VOCs, 1 wt%-Pt/TiO2 catalysts using metal as a doping element have shown amazing potential in many fields. However, achieving high catalytic performance at relatively low temperatures based on the activation of molecules is still a formidable challenge owing to the catalytic activity being highly dependent on temperature. Here, the role of the rare earth metal Ce in the catalytic oxidation of ethane was studied by preparing Pt/CexTi1−xO2 (x = 0, 0.002, 0.005, 0.01, 0.02, and 0.05) catalysts. When the Ce/(Ce+Ti) molar ratio was 0.01, Pt/Ce0.01Ti0.99O2 achieved 90% ethane conversion at 436 °C. This reaction temperature is 15% lower than that for Pt/TiO2. The characterization results show that the doping of Ce caused lattice expansion of TiO2 and its distortion brought about by oxygen vacancies. Additionally, the appropriate amount of Ce-doping can alter the interaction between the active component Pt and the carrier TiO2, thereby improving the activity and concentration of the active surface lattice oxygen species of the catalyst. These results provide a foundation for the design of the catalytic oxidation of VOCs under mild operating conditions. [ABSTRACT FROM AUTHOR]

The precipitation and dissolution processes of CaCO 3 are essential to the marine carbon cycle and are relevant to climate research. Nevertheless, one of the nagging questions is why the precipitation of CaCO 3 rarely occurs without the help of biological activity even in the surface seawater, where the calcite saturation state (Ω, expressed as the ratio of the calcium and carbonate ion concentration product to the stoichiometric solubility constant of calcite) is up to 5, but commonly takes place in hard-water lakes, springs and the low-salinity zone (practical salinity <5) of estuaries. Studies have found that Mg2+ plays a significant role in inhibiting all aspects of CaCO 3 precipitation, namely crystal formation, solubility, and precipitation rate. However, whether the presence of Mg2+ in seawater is sufficient to inhibit CaCO 3 precipitation has not been clearly stated, and the specific inhibitory role of Mg2+ in CaCO 3 precipitation still requires clarification. In this study, we used four different seed materials to induce CaCO 3 precipitation in artificial seawater of four Mg:Ca ratios and examined the crystal morphologies of the resulting precipitates using scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). We found that Mg2+ inhibits the precipitation at the first stage of nucleation, which drastically increases the difficulty of calcite nucleation. At a seawater Mg:Ca ratio of 5.2, aragonite preferentially nucleates instead of calcite. Among the tested materials, only calcite and aragonite seeds exhibit marked catalysis of CaCO 3 precipitation, indicating that not all the particles in natural seawater can catalyze CaCO 3 precipitation. Our results demonstrate while the precipitation of CaCO 3 is inhibited by Mg2+ at all stages, the inhibition at the nucleation stage is the main reason massive spontaneous CaCO 3 precipitation does not occur under the surface seawater conditions, supporting the notion that the incorporation of foreign ions such as Mg2+ increases the surface energy and the solubility of the overgrowth or cluster, and thus inhibits CaCO 3 precipitation. • CaCO 3 precipitation in seawater is primarily inhibited in the nucleation stage. • Only particles of CaCO 3 crystal structure promote CaCO 3 precipitation effectively. • Mg2+ inhibits CaCO 3 precipitation by increasing the energy needed for nucleation. [ABSTRACT FROM AUTHOR]

Based on thermal–fluid–solid coupling law in coal and gas outburst, a multi-physical field numerical analysis model is built for the whole outburst process. The response laws of stress, gas pressure, temperature, and seepage in different areas and different time nodes around coal and rock mass in the coal and gas outburst under high stress condition are discussed. Research results show: Firstly, the stress response law of the coal and rock mass around the burst hole is initial vibration–sudden attenuation–late stability. Secondly, the gas pressure response law in different areas is that the gas pressure response rate decreases gradually with the increase of the distance from the outburst. Thirdly, the adsorbed gas contained in the broken coal near the outburst port is desorbed rapidly and expands to do work, and the temperature changes dramatically after outburst occurs. In contrast, with the increase of stress, the proportion of elastic potential in total coal and gas outburst energy increases, and the proportion of elastic potential is positively correlated with stress. The critical gas pressure under the energy condition of coal and gas outburst decreases with the increase of stress. It illustrates that the lower gas pressure can also meet the energy condition of coal and gas outburst under high stress. [ABSTRACT FROM AUTHOR]