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Converting triacylgycerols (TAGs) from edible oils and fats into structured diacylglycerols (DAGs) is meaningful for reducing obesity. Camellia oil, rich in linoleic acid, has the potential to form structured linoleic acid-1,3-diacylglycerol (LA-1,3-DAG) nutrients in the industry. In this research, the physicochemical properties of modified Camellia oil (MCO) by enzymatic esterification were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS), Differential Scanning Calorimetry (DSC), High Performance Liquid Chromatography-Evaporative Light Scattering Detection (HPLC-ELSD), and Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS). The relationship between reaction conditions and the DAG compositions is disclosed using multiple factors. It is found that high constituents of DAG increase the melting and crystallization temperature of MCO, lipase Novozym 435 gives the best yield of targeted nutrients (DAG, 1,3-DAG, LA-DAG), and the mixture of lipases, Lipozyme TL IM and Lipozyme RM IM, shows a synergistic effect in the synthetic process of DAG. Subsequently, MCO containing 65.4% DAG, 54.7% LA-DAG, and 47.6% 1,3-DAG content at optimal conditions (2% enzyme dosage, 4 h reaction time, 2.4:1 substrate molar ratio, 25.8% t-butanol as solvent, 60°C temperature) has been obtained and purified using silica column to obtain the final DAG oil containing 96.1% DAG, 64.7% 1,3-DAG, and 78.4% LA-DAG. High constituents of structured DAG oil rich in LA-1,3-DAG can be obtained by enzymatic esterification for industrial production.

Diacylglycerol (DAG)-enriched oil has been attracting attention because of its nutritional benefits and biological functions, although the composition of its various free fatty acids (FFAs) and an unclear relationship between substrate and yield make it difficult to be identified and qualified with respect to its production. In the present study, linoleic acid-enriched diacylglycerol (LA-DAG) was synthesized and enriched from Camellia oil by the esterification process using the combi-lipase Lipozyme TL IM/RM IM system.The relationship between FFA composition and DAG species productivity was revealed. The results showed that heterogeneous FFA with a major constituent (more than 50%) exhibited higher DAG productivity and inhibited triacylglycerol productivity compared to homogeneous constituents. Joint characterization by high-performance liquid chromatography-evaporative light scattering detection, gas chromatography-mass spectrometry and ultra-performance liquid chromatography-heated electrospray ionization-tandem mass spectrometry identified that DAG components contained dilinoleic acid acyl glyceride, linoleyl-oleyl glyceride and dioleic acid acyl glyceride in esterification products. Under the optimum conditions, 60.4% 1,3-DAG and 61.3% LA-DAG in the crude product at 1 h reaction were obtained, and further purified to 81.7% LA-DAG and 94.7% DAG via silica column chromatography.The present study provides a guideline for the identification of DAG species, as well as a structure-guided preparation method of DAG-enriched oils via the cost-effective combi-lipase. © 2022 Society of Chemical Industry.

The pore-throat structures play a dominant role in the evaluation of properties of tight sandstone, but it remains difficult to determine the related parameters and understand their impact on reservoir quality. Hence, toward this end, we analyze the experimental data that are indicative of the pore-throat system, then we investigate the effect of fractal dimensions of pore-throat structures on petrologic and physical properties, and finally, the optical observations, fractal theory, and prediction model were integrated to explore the qualities of various reservoir types in tight sandstones. The results show that the fractal dimensions of the mercury intrusion curve correspond to three pore-throat types and those of the mercury extrusion curve could correspond to two pore-throat types. Five types of reservoirs were identified, the best reservoir type has a high percentage of interparticle and dissolution pores but a low proportion of clay-related pores, and the differences in pore-throat connectivity of various types affect storage capacity significantly. The storage ability prediction models of various reservoir types are raised by integrated experimental data. This work employed a comprehensive fractal theory based on capillary pressure curves and helps to explore how pore-throat systems influence reservoir quality in tight sandstones.

The decomposition of NH3 for hydrogen production was studied using Ni/La2O3 catalysts at varying compositions and temperatures prepared via surfactant-templated synthesis to elucidate the influence of catalyst active metal content, support composition and calcination temperature on the catalytic activity. The catalytic performance of all samples was studied between 300 and 600 °C under atmospheric pressure. The catalytic activity of the sample were as follows: 10Ni/La2O3-450 > 10Ni/La2O3-550 > 10Ni/La2O3-650 ≈ 10Ni/La2O3-750 ≈ 10Ni/La2O3-850. The excellent activity (100%) of 10Ni/La2O3-450 could be due to the high surface area, basicity strength and concentration of surface oxygen species of the catalyst as evidenced by BET, CO2-TPD and XPS. In addition, to adjust the activity of the catalyst support, the molar ratios of Mg and La were varied (1:1, 3:1, 5:1, 7:1 and 9:1). The 5Ni/5MgLa (5:1 M ratio) was found to be the most active (100%) relative to other Ni/MgLa formulations. Furthermore, the Ni content in the Ni/5MgLa sample was adjusted between 10 and 40 wt%. Increasing the Ni content of the catalysts increased NH3 conversion with the 40 wt% Ni formulation demonstrating complete NH3 conversion at 600 °C and a high gas hourly space velocities (GHSV) (30,000 mL∙h−1∙gcat−1).

A novel fracturing fluid system with wettability was prepared. XRD and TGA of the polymer were measured. Rheology and SEM experiments showed that the fracturing fluid had a dense network structure. The microstructures of the gel breaking fluid were obtained using SEM and TEM tests, which demonstrated more obvious crosslinking. Contact angle and wetting function of the gel breaking fluid were evaluated on sandstone. The NFW fracturing fluid showed excellent rheological properties at 90 °C. The surface tension of the gel breaking fluid was relatively low, being 20 mN m−1. The WA, BET data and zeta potential of the NFW gel breaking fluid suggested that the material was absorbed on the sandstone surface and a bilayer was formed. Meanwhile, CT and AFM studies indicated that the imbibition effect of the gel breaking fluid could obviously be observed on the sandstone. The contact angle increased to 146° when the sandstone was immersed in solution, which suggested that the wettability of the rock was changed. The imbibition efficiency of NFW is higher than that of water. Thus, this fracturing fluid with wettability could be an alternative for development in tight oil reservoirs.

Ammonia has become an attractive source for COx-free hydrogen production for fuel cell applications. The catalytic performance of Ce0.6Zr0.3Y0.1O2 solid solutions supported Ni, Co and Ni Co bimetallic catalysts are evaluated in the temperature range of 300–600 °C at atmospheric pressure. Due to the synergistic effect between Ni and Co, CZY supported Ni Co bimetallic catalysts show higher ammonia decomposition activity compared to Ni or Co monometallic samples. The Ni Co bimetallic catalyst with the Ni/Co mass ratio of 1/9 exhibits the highest NH3 conversion with the GHSV of 6000 mL h−1 gcat−1, which reaches 100% conversion at 600 °C. Moreover, the Ni1Co9/CZY catalyst shows good thermal stability during the 72 h reaction time. The Ni1Co9/CZY have the highest total H2-uptake of 0.35 mmol‧g−1 and the highest TOFH2 value (40.57 min−1) at 350 °C among all the catalysts. Our characterization confirms the formation of Ni Co alloy is responsible for the high activity of Ni1Co9/CZY catalyst for the ammonia decomposition.

Herein, a novel ultra-high salt hydrophobic associated polymer, UUCPAM, was prepared using acrylamide, acrylic acid, 2-acrylamide-2-methyl propane sulfonic acid and the hydrophobic monomer UUC. Polymerization exothermic test results indicated that the increase in the hydrophobic monomer content led to an increase in the exothermic time, which is considerably conducive to the formation of hydrophobic structures. The scanning electron microscopy and transmission electron microscopy studies showed that the polymer had complex network structures and that this phenomenon was considerably obvious in NaCl solution. The fluorescence probe experiment verified that the critical association concentration of this polymer decreased with an increase in the hydrophobic monomer. Rheology studies indicated that the polymer had good temperature and shear resistance in NaCl solution. Moreover, the apparent viscosity of the polymer remained above 80 mPa s when 0.3 wt% UUCPAM was added at 170 s−1 in 20 000 mg L−1 NaCl solution at 90 °C. The storage modulus that indicated strong elasticity increased with an increase in the polymer concentration. Meanwhile, the number of hydrophobic micro-zones increased, thus forming dense network structures. Therefore, the polymer was found to have excellent salt resistance and extensive application prospects.

The bioactive peptides derived from sweet apricot kernel residue after oil extraction exhibit different bioactivities, but their structure-activity relationships have not yet been established. In this research, the antioxidant activities (hydroxyl, superoxide anion, DPPH radical scavenging capacity and iron-binding ability) of sweet apricot kernel protein hydrolysates (SAKPHs) obtained by different enzymes at the temperature range (37–70 °C) were evaluated. The amino acid sequences of the hydrolysates by different enzymes were identified by LC-ESI-MS/MS. The results showed that five novel antioxidant peptides with Lysine at the C-terminal end were found in the Neutrase’ SAKPHs. Two peptides with Serine-terminal end in the Alcalase’ SAKPHs and with N-terminal end in the Papain’ SAKPHs were obtained respectively. Three atypical peptides were detected in the Flavourzyme’ SAKPHs. The SAKPHs by the Alcalase (SAKPHs-A) at 50 °C had highest degree of hydrolysis and a relatively smaller molecular weight distribution compared with the other three proteases, and presented the higher antioxidant activity. The N-terminal peptide SHNLPILR containing a side chain combination of aspartic acid and histidine contributes to the stronger antioxidant activities of SAKPHs-A. This research supplies a guideline for functional peptides released from dietary proteins by the utilization of specific enzymes in the food industry.

Vernadite is a poorly crystalline phyllomanganate that widely distributed in natural environments, and plays a pivotal role in the geochemical transformations of heavy metal and other pollutants. Though many works have done about the reaction mechanisms between vernadite-like minerals and As(III)/Cr(III), the effects of some basic structure characteristics of the mineral, such as Mn average oxidation state (AOS), on the oxidation of As(III)/Cr(III) are not fully understood. In this study, vernadite samples with different Mn AOSs but almost the same particle sizes (Ver and Ver20) were synthesized, characterized, and their reactivities towards As(III)/Cr(III) oxidation and As(V)/Cr(VI) adsorption were compared. It is found that Ver and Ver20 have almost the same point of zero charge (PZC), but ver20 has increased contents of layer Mn(III) at particle edges and interlayer Mn(III) and Mn(II), thus greatly reduced Mn AOS. Decrease in Mn AOS greatly reduces the oxidation capacity and initial reaction rate (Kobs) of this mineral towards As(III) on mineral-water interfaces. The apparent As(III) oxidation amount and Kobs by Ver are 202 ± 8 mmol kg−1 and 0.3515 min−1 while that by Ver20 are 162 ± 7 mmol kg−1 and 0.0139 min−1. The oxidation capacity and Kobs for Cr(III) by these vernadie samples are also decreased but in a less extent compared to that in As(III) oxidation, e.g. Cr(III) oxidized by Ver and Ver20 are 2895 ± 47 and 1974 ± 109 mmol kg−1 and the Kobs are 0.0439 and 0.0169 min−1 respectively. Adsorption density of As(V) or Cr(VI) on Ver20 is ∼15–18% higher than that on Ver. These results suggest the more important role Mn AOS plays in As(III) oxidation than Cr(III) oxidation, and helps understand the geochemical behaviors of these toxic metals in natural environments mediated by Mn oxide minerals.

The fabrication of nanomaterial is a crucial issue in heterogeneous catalysis for on-site generation of hydrogen in proton exchange membrane fuel cell to achieve excellent performance for ammonia decomposition, and their effects of morphologies are still mysterious in the structure-reactivity relationship. In order to disclose it, three kinds of CeO2 supports with three-dimensionally ordered mesoporous structure (3DOM), nanotubes (NT) and nanocubes (NC) were synthesized by nanocasting of a mesoporous silica KIT-6 template with cubic Ia3d symmetries, hydrothermal method with and without urea, respectively. Various characterization methods (XRD, BET, H2-TPR, CO-TPD, TEM and XPS) were used to characterize the structure-reactivity relationship of catalysts. The Co/CeO2-3DOM catalyst had higher H2 producing rate (4.2 mmol/min･gcat) than Co/CeO2-NC (3.5 mmol/min･gcat) and Co/CeO2-NT (3.2 mmol/min･gcat) under the reaction conditions of 500 °C and GHSV = 6000 mL/gcat･h. The Co/CeO2-3DOM catalysts presented Co nanoparticles with mean size of 5.2 nm, and the highest surface Co concentration (5.12%) and Ce3+/Ce4+ ratio (0.53). Its high activity is attributed to higher surface area and more surface oxygen vacancies. The specific surface area and surface oxygen vacancy are significantly affected by the morphology of CeO2 support. The more mechanism insight of the structure-activity relationship for ammonia decomposition has been revealed.

RIGID algorithm was recently proposed to identify the contact state between spherical particles and arbitrary-shaped walls, demonstrating significantly improved robustness, accuracy and efficiency compared to existing methods. It is an important module when coupling computational fluid dynamics with discrete element model to simulate particle transport in porous media. The procedure to identify particle and surface contact state is usually time-consuming and takes a large part of the CPU time for discrete element simulations of dense particle flow in complex geometries, especially in cases with a large number of particle–wall collisions (e.g. particle transport in porous media). This paper presents a new version of RIGID algorithm, namely ERIGID, which further improves the efficiency of the original algorithm through a number of new strategies including the recursive algorithm for particle-face pair selection, angle-testing algorithm for determining particle-face relations and the smallest index filter for fast rejection and storage of time invariant. Several specially designed numerical experiments have been carried out to test the performance of ERIGID and verify the effectiveness of these strategies. Finally, the improved algorithm is used to simulate particle transport in a rock treated as a porous medium. Our numerical results reveal several important flow phenomena and the primary reason for particle trapping inside the rock.

Methanol steam reforming is a promising process for the generation of hydrogen. In this study, Au catalysts supported on modified montmorillonite were prepared and their catalytic activity for methanol steam reforming was investigated at 250–500 °C. The physical and chemical properties of the as-prepared catalysts were characterized by Brunauer–Emmet–Teller method (BET), X-ray diffraction (XRD), transmission electron microscopic (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Inductively Coupled Plasma (ICP), and thermogravimetrc analysis (TGA). For the catalysts examined, Au-Ti-Ce/Na-ABen exhibits the best catalytic performance with methanol conversion of 72% and H2 selectivity of 99% at 350 °C. This could be attributed to Au, Ce, and Ti species which form a solid solution and move into the interlayer space of the bentonite leading to a high surface area, large average pore volume, large average pore diameter, and small Au particle size. We considered that the synergistic effect of the crosslinking agent, the Ce species, and the Au active sites were responsible for the high activity of Au-Ti-Ce/Na-ABen catalyst for methanol steam reforming.