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This paper aims to explore the influence of the reinforcement included either glass beads (GBs) or carbon fiber (CF) on the reinforced polyamide 12 (PA12) composite samples prepared by selective laser sintering (SLS).

In this paper, the microstructure and mechanical properties are investigated, and the results are compared with those obtained for non-reinforced pure PA12 samples prepared by SLS.

The tensile fracture surface of the non-reinforced pure PA12 sample presents strong micro-deformation within the crack origination zone between the melted PA12 matrix and the un-melted PA12 particle cores. As a result, the pure PA12 sample exhibits the greatest maximum elongation. The maximum tensile strength is obtained for the CF reinforced sample because of the strengthening effect of CF and the relatively good bonding between CFs and the PA12 matrix. The minimum tensile strength is obtained for the GB reinforced PA12 sample because of the relatively weak bonding between GBs and the PA12 matrix.

These results demonstrate that the characteristics of the interfaces between the reinforcement and the PA12 matrix have an important influence on the fracture mechanisms and mechanical properties of PA12 composites fabricated by SLS.

The purpose of this paper is to examine the effects of energy technological innovation on carbon emissions in China from 2001 to 2016.

Conditional mean (CM) methods are first applied to implement our investigation. Then, considering the tremendous heterogeneity in China, quantile regression is further employed to comprehensively investigate the potential heterogeneous effect between energy technological innovation and carbon emission intensity.

The results suggest that renewable energy technological innovation has a significantly positive effect on carbon emission intensity in lower quantile areas and a negative effect in higher quantile areas. Contrarily, fossil energy technological innovation exerts a negative correlation with carbon emission intensity in lower quantile areas and a positive effect on carbon emission intensity in higher quantiles areas.

Considering that energy consumption is the main source of CO₂ emissions, it is of great importance to study the impact of energy technological innovation on carbon emissions. However, the previous studies mainly focus on the impact of integrated technological innovation on carbon emissions, ignoring the impact of energy technological innovation on carbon emissions mitigation. To fill this gap, we construct an extended STIRPAT model to examine the effects of renewable energy technological innovation and fossil energy technological innovation on carbon emissions in this paper. The results can provide a reference for the government to formulate carbon mitigation policies.

Oil is crucial for industrial development. This paper investigates the impacts of oil price changes on China's industrial growth and examines whether the impacts are asymmetric. The estimations can help determine how oil price shocks are transmitted throughout the economy.

This paper adopts West Texas Intermediate (WTI) crude oil price and industrial sector output and uses monthly data. The recently developed nonlinear autoregressive distributed lag (NARDL) model is employed to illustrate the effects in both the short term and long term. Importantly, under NARDL framework, this paper examines whether the impacts are asymmetric by decomposing oil price shocks into their positive and negative partial sums.

The empirical results prove clear evidence of asymmetries in the short term, long term or both terms. Specifically, some sectors benefit from, rather than suffer from higher oil prices, even some energy-intensive sectors, i.e. C31 (Smelting and Pressing of Ferrous Metals) and C32 (Smelting and Pressing of Non-ferrous Metals). However, the effects on some other energy-intensive sectors appear insignificant. Additionally, the results prove significantly negative responses in some sectors in the long term, and most of these sectors are in the top half of the ranking by energy consumptions.

This paper studies the economic responses at a disaggregated level by employing industry-level data. NARDL method is used to decompose oil price changes into their increases and decreases and investigate the asymmetries in the impacts of oil price changes.

The purpose of the paper is to study the dyeing process of three-dimensional-printed (3DP) fabrics, and then study the wearability of the fabrics before and after dyeing to provide a feasible dyeing method of 3DP clothes.

In this regard, the thermoplastic polyurethane (TPU) was applied during the process of 3DP. Then, the imitation twill weave (ITW) was printed with fused deposition modeling (FDM) technology using TPU and the suspension of Disperse Blue 2BLN (as a dye) was prepared. After that, the single factor analysis and orthogonal experiment of dyeing were combined to obtain the optimized dyeing process. And then, ITW fabrics were dyed through the weak acid-low temperature dyeing method. In the end, in order to discuss the wearability of ITW fabrics, the dyeing experiments, including permeability, wrinkle recovery angle, bending rigidity, crock fastness and washing colorfastness were carried out.

The surface morphology of TPU before and after spinning was established by field emission scanning electron microscopy (FE-SEM), which was confirmed the surface of TPU getting smoother after spinning. The wearability of the fabric after dyeing was not affected compared with before dyeing. Moreover, both colorfastness grades were above 4–5 with high colorfastness.

The article provides a method for 3DP dyeing, which can solve the problem of a single color. And the wearability demonstrates that 3DP fabrics after dyeing-based TPU have more value for clothing than before dyeing.

The purpose of this study was to investigate the inhibitive action of some green leaves on Monel 400 alloy in acidic media.

Green leaves of Mespilus japonica, Ricinus communis L and Vitis vinifera were immersed in methanol solutions, separately, and filtrated after 48 h of immersion; the obtained filtrates were examined as corrosion inhibitors of Monel 400 alloy in hydrochloric acid solution (1.0M HCl). The performance of these inhibitors was evaluated using electrochemical impedance spectroscopy and potentiodynamic polarization. The effect of temperature on corrosion behavior of Monel 400 was also studied.

The results obtained showed that all tested inhibitors performed as good corrosion inhibitors. The inhibition process is attributed to the adsorption of the inhibitors on Monel surface. The adsorption behavior was found to follow Langmiur isotherm. The inhibition efficiencies of extracts increased with increasing the concentration of each inhibitor and deceased with increasing the temperature.

Practical implication These inhibitors could have application in industries where hydrochloric solutions were used to remove the surface impurities of Monel 400.

This paper helps to find new corrosion inhibitors that are safe and eco-friendly.