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To research the flow-induced vibration characteristics of the natural gas loop, unsteady numerical simulation is carried out on the loop calculation model under different ambient temperatures and different flow rates, and the influence of different flow rates on the dynamic characteristics of the flow field and its induced vibration characteristics is obtained. The results show that the inherent frequency of the natural gas loop increases slightly under the action of heat–fluid–solid coupling. The maximum equivalent stress of the loop increases with the increase in ambient temperature under low flow conditions, but it is almost constant under high flow conditions. The smaller the cross-sectional area of the loop pipeline inlet, the greater the pressure, and the more significant the pressure gradient along the flow direction. The pressure pulsation of monitoring points in the pipeline under different flow rates presents different rules, and the pulsation amplitude of pipes with different diameters is different, among which the amplitude of the pipe with a diameter of 250 mm is the largest and that of the pipe with a diameter of 150 mm is the smallest. The pressure pulsation signals are concentrated in the low-frequency band of 0–10 Hz, and the range of the band decreases with the increase in the flow rate. The vibration frequency of the loop structure is close to the fluid pressure pulsation frequency and the inherent frequency under the action of heat–fluid–solid coupling, which causes a resonance of about 2 Hz.

A new environmental ban has forced the restructure of open dumps in China since 1 July 2011. A technical process was established in this study that is feasible for the upgrade of open dumps through restructuring. The feasibility of restructuring and the benefit of greenhouse gas emission reductions were assessed according to field surveys of five landfills and four dumps in Nanjing. The results showed that the daily processing capacities of the existing landfills have been unable to meet the growth of municipal solid waste (MSW), making restructuring of the landfills imperative. According to an assessment of the technical process, only four sites in Nanjing were suitable for upgrading. Restructuring the Jiaozishan landfill effectively reduced the leachate generation rate by 5.84% under its scale when expanded by 60.7% in 2015. CO2 emissions were reduced by approximately 55,000–86,000 tons per year, in which biogas power generation replaced fossil fuels Fossil fuels accounted for the largest proportion, up to 45,000–60,000 tons. Photovoltaic power generation on the overlying land has not only reduced CO2 emissions to 26,000–30,000 tons per year but has also brought in continuing income from the sale of electricity. The funds are essential for developing countries such as China, which lack long-term financial support for landfill management after closure.

Production of biodiesel from yellow grease (waste cooking oil and waste animal fats) is fast emerging as a promising alternative to address the twin challenges before the biodiesel industry today-fluctuation in prices of vegetable oil and the food versus fuel debate. Yellow grease has a high percentage of free fatty acids (FFA) and proves to be an unsuitable feedstock for biodiesel production from commercially viable alkali-catalyzed production systems due to saponification problems.“Green” methodologies based on heterogeneous solid acid catalyzed reactions have the potential to simultaneously promote esterification and transesterification reactions of yellow grease to produce biodiesel without soap formation and offer easy catalyst separation without generation of toxic streams. This paper presents kinetic studies for the conversion of model yellow grease feeds to biodiesel using a heteropolyacid supported on alumina (HSiW/Al2O3) using a batch autoclave. Three model yellow grease feeds were prepared using canola oil with added FFA such as palmitic, oleic and linoleic acid. A pseudo homogeneous kinetic model for the parallel esterification and transesterification was developed. The rate constants and activation parameters for esterification and transesterification reactions for the model yellow grease feeds were determined. The rate constants for esterification are higher than the transesterification rate constants. The kinetic model was validated using the experimental biodiesel data obtained from processing a commercial yellow grease feed. The kinetic model could be used to design novel processes to convert various low-value waste oils, fats and non-food grade oils to sustainable biodiesel. Keywords: Yellow grease, Canola oil, Free fatty acids, Heteropolyacid, Kinetics for esterification and transesterification

In this study, we investigated the influence of overall financial development and its components on energy consumption using the panel data of 120 countries and the generalized method of moments (GMM). By dividing the sample into developed and developing countries, we further examined the national differences of the impact of financial development on energy consumption. The empirical results indicate that the overall financial development significantly positively impacts energy consumption from a worldwide perspective, and its two components (financial institution and the financial market) have the same effect. The analysis of national differences indicates that the financial development also positively impacts energy consumption in developing countries but with no obvious effect in developed countries. The results also suggest that financial development cannot be used to restrain the increase in energy consumption from the global perspective, and policymakers in developing countries must balance the relationship between the development of the financial sector and energy consumption.

Research and clinical applications have demonstrated that the effects of tendon allografts are comparable to those of autografts when reconstructing injured tendons or ligaments, but allograft safety remains problematic. Sterilisation could eliminate or decrease the possibility of disease transmission, but current methods seldom achieve satisfactory sterilisation without affecting the mechanical properties of the tendon.Peracetic acid-ethanol in combination with low-dose gamma irradiation (PE-R) would inactivate potential deleterious microorganisms without affecting mechanical and biocompatible properties of tendon allograft.Controlled laboratory design.HIV, PPV, PRV and BVDV inactivation was evaluated. After verifying viral inactivation, the treated tendon allografts were characterised by optical microscopy, scanning electron microscopy and tensile testing, and the cytocompatibility was assessed with an MTT assay and by subcutaneous implantation.Effective and efficient inactivation of HIV, PPV, PRV and BVDV was observed. Histological structure and ultrastructure were unchanged in the treated tendon allograft, which also exhibited comparable biomechanical properties and good biocompatibility.The preliminary results confirmed our hypothesis and demonstrated that the PE-R tendon allograft has significant potential as an alternative to ligament/tendon reconstruction.Tendon allografts have been extensively used in ligament reconstruction and tendon repair. However, current sterilisation methods have various shortcomings, so PE-R has been proposed. This study suggests that PE-R tendon allograft has great potential as an alternative for ligament/tendon reconstruction.Sterilisation has been a great concern for tendon allografts. However, most sterilisation methods cannot inactivate viruses and bacteria without impairing the mechanical properties of the tendon allograft.Peracetic acid/ethanol with gamma irradiation can effectively inactivate viruses and bacteria. Meanwhile, tendon allografts sterilised by this method maintain their physiological tendon structure, biomechanical integrity and good compatibility.

Abstract Previous studies have shown that titanium-based glazes containing silicon and calcium tend to crystallize into titanite. In this work, ZnO was found to be an effective additive to produce rutile but not titanite. Images of the micromorphology showed that the glaze doped with 8 wt% ZnO was UV–VIS–NIR of acicular rutile and granular silica. The refractive index of crystalline rutile is higher than that of crystalline titanite, which leads to higher reflectance in the near-infrared range. However, excessive rutile counteracted this improvement in the UV–VIS–NIR spectrum reflectance of solar energy because it decreased the visible spectrum reflectance. As a result, the best ratio of added ZnO was confirmed to be 2 wt%.

Abstract In this study, crude cellulose derived from cornstalk, after bleaching, was used as raw material for the synthesis of sodium carboxymethyl cellulose (CMC) by reacting with the cellulose with NaOH and chloroacetic acid at 75 °C for 1.5 h. Effects of alkali dosage, concentration of chloroacetic acid on the physical and chemical properties of the CMC products were investigated. It was revealed that the reactants alkali reagent/chloroacetic acid/cellulose at the molar ratio of 4.6:2.8:1and 4:2.5:1, or at the molar ratio of NaOH/ClCH 2 COOH ≈1.6–1.64, resulted in CMC products of relatively high water solubility. The viscosity-average molecular weight M v of these two CMC products obtained at molar ratios of 4.0:2.5:1 and 4.6:2.8:1 is in the range of 1.94 × 10 4 –2.48 × 10 4 g mol −1 , and the average DS of the two products are 0.57 and 0.85, respectively. As the solute concentration is above 2 wt%, the viscosity of the CMC-water solution exhibits nonlinear (exponential) increasing with increasing the solute concentration (typical of non-Newton fluids).

Wide‐bandgap (WBG) perovskite solar cells (PSCs) are acknowledged as promising candidates for tandem solar cells and building photovoltaics. It is well known that cesium‐based all‐inorganic halide WBG perovskites possess the comparable optoelectronic properties as the organic–inorganic counterparts, but exhibit superior thermal stability. Among them, CsPbIBr2 is considered a feasible material for tandem solar cells after balancing the bandgap and stability of the inorganic perovskite. However, CsPbIBr2 PSCs are often subjected to drastic interfacial charge recombination especially in carbon‐based device structure derived from the chemical bonding defects (i.e., uncoordinated Pb2+) naked on CsPbIBr2 soft lattice, which dramatically limits overall efficiency of CsPbIBr2 WBG PSCs. Herein, a trimethyl ammonium salt hexyltrimethylammonium bromide is presented for CsPbIBr2/carbon interfacial modification. Benefiting from the −N+(CH3)3 passivation effect and −C6H13 hydrophobic alkyl chain, the optimal device with highly smooth morphology and sufficient charge extraction exhibits a champion power conversion efficiency of 11.24% and improved long‐term stability with 99.7% and 79.7% efficiency retention under dry air atmosphere and continuous 85 °C thermal stress, indicating the valuable potential application of the lattice solidified CsPbIBr2 WBG PSCs.

To meet the increasing demands of precision agricultural and environmental management, more abundant and accurate information is needed to describe soil organic carbon (SOC) vertical variation. Based on 923 soil profiles (collected at the depths of 0–15, 15–30, 30–60, 60–90, 90–120, and 120–150 cm) in the central area of Changhua County, Taiwan, the distribution curve of the SOC content of each profile was fitted by the equal-area spline model, and it was possible to obtain the SOC content at all depths. Taking the 0–5 cm (L1), 5–10 cm (L2), and 10–15 cm (L3) sub-layers as examples, their SOC contents and stocks were compared to the mean values of the average 5-cm-thick sub-layers (Lm) derived from the value of the 0–15 cm layer. The results indicated that the SOC contents and stocks both reduced with increasing soil depths. The mean SOC contents of L1, L2, and L3 were 22.1, 21.0, and 18.7 g·kg−1, respectively, with significant variation, and the values of L2 and L3 were 5.0% and 15.4% lower than that of L1. Similarly, the mean SOC stocks were 1.29, 1.25, and 1.16 kg·m−2 of the L1, L2, and L3 layers, also with significant variation, and the values of L2 and L3 were 4.0% and 10.1% lower than that of L1. Meanwhile, it was found that the SOC content and stock of Lm were both close to the corresponding values in L2, but were significantly different to that of L1 and L3. Furthermore, the interpolation contours of the SOC contents and stocks in L1, L2, and L3 by digital soil mapping also presented regular variation with increasing soil depths, while the contours of Lm had nearly identical patterns to that of L2. The results demonstrate that the typically used mean SOC contents with certain thicknesses calculated from the sampling layer can only approximately inflect the SOC situation at intermediate depths, but the SOC content in the upper and lower parts within the sampling layer varies greatly. Therefore, the actual distribution of SOC varies gradually depending on the soil depth. This study indicates that the combination of the equal-area spline model and digital soil mapping can greatly enrich the current soil SOC database and provide more abundant and accurate SOC content and stock information for precision agricultural and environmental management based on legacy soil database.