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Abstract The purpose of this paper is to investigate the influence of blending methods on the co-gasification of petroleum coke and lignite with CO 2 using a thermogravimetric system at 0.1 MPa. The weight loss curves, XRD analysis, SEM images, BET specific surface area, were investigated. It was observed that petroleum coke shows a low reactivity because of the graphitic carbon structure, low catalyst content and small specific surface area. Blending with lignite can get a high reactivity. The co-gasification reactivity was significantly influenced by blending methods. Wet grinding is much effective than dry grinding. Long grinding time made lignite show greater BET specific area. And the sample in long grinding time has more association chances between petroleum coke and AAEM species. The co-gasification reactivity increases linearly with a rise of BET specific area.

Using a large dataset of well-level natural gas production from Wyoming, we evaluate the respective roles played by market signals and geological characteristics in natural gas supply. While we find well-level production of natural gas is primarily determined by geological characteristics, producers respond to market signals through drilling rates and locations. Using a novel fixed effects approach based on petroleum-engineering characteristics, we confirm that production decline rates tend to be larger for wells with larger peak-production rates. We also find that the price elasticity of peak production is negative, plausibly because firms drill in less productive locations as prices increase. Finally, we show that drilling is price inelastic, although the price elasticity of drilling increased significantly when new technologies began to be adopted in Wyoming. Our results indicate that the popular view that shale wells have larger decline rates than conventional wells can be at least partially explained by the pattern of falling natural gas prices.

The effect of the combined application of nano-hydroxyapatite (NHAP) or nano-carbon black (NCB) on the phytoextraction of Pb by ryegrass was investigated as an enhanced remediation technique for soils by field-scale experiment. After the addition of 0.2% NHAP or NCB to the soil, temporal variation of the uptake of Pb in aboveground parts and roots were observed. Ryegrass shoot concentrations of Pb were lower with nano-materials application than without nano-materials for the first month. However, the shoot concentrations of Pb were significantly increased with nano-materials application, in particular NHAP groups. The ryegrass root concentrations of Pb were lower with nano-materials application for the first month. These results indicated that nano-materials had significant effects on stabilization of lead, especially at the beginning of the experiment. Along with the experimental proceeding, phytotoxicity was alleviated after the incorporation of nano-materials. The ryegrass biomass was significantly higher with nano-materials application. Consequently, the Pb phytoextraction potential of ryegrass significantly increased with nano-materials application compared to the gounps without nano-materials application. The total removal rates of soil Pb were higher after combined application of NHAP than NCB. NHAP is more suitable than NCB for in-situ remediation of Pb-contaminated soils. The ryegrass translocation factor exhibited a marked increase with time. It was thought that the major role of NHP and NBA might be to alleviate the Pb phytotoxicity and increase biomass of plants.

Abstract Day-ahead forecasts of direct normal irradiance (DNI) from the Integrated Forecasting System (IFS), the global model of the European Centre for Medium-Range Weather Forecasts (ECMWF), are used to simulate a concentrating solar power (CSP) plant through the System Advisor Model (SAM) to assess the potential value of the IFS in the electricity market. Although DNI forecasting from the IFS still demands advances towards cloud and aerosol representation, present results show substantial improvements with the new operational radiative scheme ecRad (cycle 43R3). A relative difference of approximately 0.12% for the total annual energy availability is found between forecasts and local measurements, while approximately 10.6% is obtained for the previous version. Results of electric energy injection to the grid from a simulated linear focus parabolic-trough system shows correlations coefficients of approximately 0.87 between hourly values of electric energy based on forecasted and measured DNI, while 0.92 are obtained for the daily values. In the context of control strategy, four operational strategies are given for different weather scenarios to handle the energy management of a CSP plant, including the effect of thermal energy storage capacity. Charge and discharge operational strategies are applied accordingly to the predicted energy availability.

Schisandra Sphenanthera polysaccharides fractions (SSPs), namely SSP40, SSP60, and SSP80, were obtained by gradient precipitation with 40 %, 60 %, and 80 % (v/v) ethanol, respectively. It was found that gradient ethanol precipitation (GEP) significantly affected the physicochemical and structural characteristics of SSPs, including molecular weight, monosaccharide composition, and surface morphology. Compared to fractions SSP40 and SSP60, SSP80 was observed to have a lower molecular weight (22.58 kDa) and certain specific monosaccharide composition, such as lower glucose content and higher galactose, arabinose, rhamnose, and galacturonic acid content. Furthermore, the apparent porosity of the SSPs increased with increasing ethanol concentration in GEP. After fermentation at 37 °C for 48 h, fraction SSP80 prominently promoted the production of more short-chain fatty acids (SCFAs), increasing from an initial 1.39 ± 0.08 to 26.75 ± 0.54 mmol/L. The SSP fraction types extracted by GEP greatly affected the modulation of the intestinal microflora at different levels. The SSP80 fraction with excellent structure demonstrated the best ability to modulate the intestinal microflora by increasing the relative abundance of Bacteroides, Faecalibacterium and Dialister and decreasing the relative abundance of Escherichia-Shigella. The remarkable differences in modulating the intestinal microflora confirmed the importance of carefully selecting GEP to fraction SSPs that promote health.

Poria cocos (Schw.) Wolf, an important medicinal and food fungus, is well known in East Asia. Due to growing market demand, long cultivation period, and consumption of pine trunk during cultivation, developing alternative methods for producing P. cocos and/or its active components is of interest. In the present study, the effects of different culture methods on biomass and accumulation of four triterpenoids were investigated. The ethanol extract of fermented mycelium (EFM) was orally administered to rats. Urine output and concentrations of electrolytes (Na+, K+, and Cl-) were measured. Our results showed that mycelia grew better under continuous shaking culture condition (7.5 g DW·L-1), and higher triterpenoid levels were accumulated in two-stage culture (112 mg·L-1, 2.03%). The optimal starting time of static culture for triterpenoid yield was 4th d after shaking culture. Single administration of middle and high dose of EFM significantly increased urine output, Na+ and Cl- excretion, and Na+/K+ ratio. These results suggested that ethanol extract of cultured mycelia showed significant diuretic activity in rats and two-stage culture of P. cocos could be an alternative way to produce mycelia and triterpenoids.

Abstract Fresh green asparagus is prone to lignify after harvest due to its high respiration rate and secretion of secondary metabolites regulated by enzymes generated during storage. In this work, a dense hemicellulose-based coating containing hemicellulose, cellulose nanofibers, and montmorillonite (MMT) was prepared and used as a coating to reduce the respiration rate of green asparagus, with which the shelf life of green asparagus was prolonged from 5 days to 7 days. Alkyl ketene dimer (AKD) was used as a hydrophobizer and a crosslinking agent to reduce humidity sensitivity by introducing hydrophobic fatty acid chains to nanoparticles for increased structural stability and respiratory barrier property hemicellulose-based film in high humidity conditions. Our study proved that AKD modified coating with nature-derived nanomaterials could effectively increase respiratory barrier property, slow down the secretion of lignification-involved enzymes, and regulating the conversion of phenolic compounds to the lignin monomers.