New plant polyphenol-derived tannic acid-based chromium-free tanning agent for sustainable and clean leather production.

This study aimed to prepare a new bio-based chromium-free tanning agent. The green epoxide monocase ethylene glycol diglycidyl ether (EGDE) was grafted with tannic acid (TA) derived from natural plant using the one-pot method to synthesize new plant polyphenol-derived tannic acid-based chromium-free tanning agents (TA-EGDE) with abundant terminal epoxides. FTIR, 1H NMR, XPS, GPC, SEM, and other analytical techniques were used to characterize tanning agents. These consequences manifested that EGDE was successfully grafted with the phenol hydroxyl group of TA. The epoxide value of TA-EGDE showed a tendency to increase and then decrease with increasing EGDE dosage, and the epoxide value of TA-EGDE-2 attained a maximum of 0.262 mol/100 g. GPC analysis showed that the formula weight of the prepared TA-EGDE was partially distributed above 5000 Da. The tanning experiment demonstrated that the shrinkage temperatures (Ts) of the TA-EGDE-tanned leathers were all higher than 81.5 °C. Compared with the traditional commercial chromium-free tanning agent (F-90, TWS), TA-EGDE-tanned leathers exhibited higher Ts and better mechanical properties. The TA-EGDE prepared in this study not only has ecological environmental protection but also provides finished leather with good moisture, heat resistance, and mechanical properties.

Highly conductive, rapid self-healing, and anti-freezing poly(3,4-ethylenedioxythiophene)/lignosulfonate-cationic guar gum ionogels for multifunctional sensors.

Soft ionic conductors exhibit immense potential for applications in soft ionotronics, including ionic skin, human-machine interface, and soft luminescent device. Nevertheless, the majority of ionogel-based soft ionic conductors are plagued by issues such as freezing, evaporation, liquid leakage, and inadequate self-healing capabilities, thereby constraining their usability in complex environments. In this study, we present a novel strategy for fabricating conductive ionogels through the proportionally mixing cationic guar gum (CGG), water, 1-butyl-3-methylimidazolium chloride (BmimCl)/glycerol eutectic-based ionic liquid, and poly(3,4-ethylenedioxythiophene)/lignosulfonate (PEDOT/LS). The resultant benefits from strong hydrogen bonding and electrostatic interactions among its constituents, endowing it with an ultrafast self-healing capability (merely 30 s) while sustaining high electrical conductivity (~16.5 mS cm-1). Moreover, it demonstrates exceptional water retention (62 % over 10 days), wide temperature tolerance (-20 to 60 °C), and injectability. A wearable sensor fabricated from this ionogel displayed remarkable sensitivity (gauge factor = 17.75) and a rapid response to variations in strain, pressure, and temperature, coupled with both long-term stability and wide working temperature range. These attributes underscore its potential for applications in healthcare devices and flexible electronics.

Assessing SDG-3 efficiency for SDG-1 by studying interplay of tourism development, poverty alleviation and sustainability.

The modern world is facing chaos of different connected issues. Achieving sustainability in the tourism industry for poverty reduction is one of them, having limited guidance for stakeholders. Thus, following SDG-3 guidelines for good well-being via tourism development could contribute to SDG-1 for no poverty. This roadmap needs scientific validation. Therefore, this research aims to determine how much of an overall impact tourism has on alleviating poverty and what factors account for the wide range of estimates of that impact. Using data from 2002 to 2020 and the ARDL model with eight variables, including (a) currency supply, (b) GDP per capita, and (c) tourism earnings higher GDP area, the current emphasis is on reducing the likelihood of any negative impacts this business may have on tourism. Lower Gross Domestic Product (GDP) regions, higher profits per capita from tourism, and reduced poverty all have a role. With a 1% significance threshold, the observed data becomes more convincing. Last, the results show that the Laotian government intends for tourism to contribute to long-term environmentally responsible financial development. In addition, the study's empirical results corroborated the conclusion that policymakers should encourage the successful expansion of the tourist industry.

Effect of Heating on Hot Deformation and Microstructural Evolution of Ti-6Al-4V Titanium Alloy.

This paper presents a systematic study of heating effects on the hot deformation and microstructure of dual-phase titanium alloy Ti-6Al-4V (TC4) under hot forming conditions. Firstly, hot flow behaviors of TC4 were characterized by conducting tensile tests at different heating temperatures ranging from 850 °C to 950 °C and heating rates ranging from 1 to 100 °C/s. Microstructure analysis, including phase and grain size, was carried out under the different heating conditions using SEM and EBSD. The results showed that when the heating temperature was lower than 900 °C, a lower heating rate could promote a larger degree of phase transformation from α to ß, thus reducing the flow stress and improving the ductility. When the temperature reached 950 °C, a large heating rate effectively inhibited the grain growth and enhanced the formability. Subsequently, according to the mechanism of phase transformation during heating, a phenomenological phase model was established to predict the evolution of the phase volume fraction at different heating parameters with an error of 5.17%. Finally, a specific resistance heating device incorporated with an air-cooling set-up was designed and manufactured to deform TC4 at different heating parameters to determine its post-form strength. Particularly, the yield strength at the temperature range from 800 °C to 900 °C and the heating rate range from 30 to 100 °C/s were obtained. The results showed that the yield strength generally increased with the increase of heating temperature and the decrease of heating rate, which was believed to be dominated by the phase transformation.