Effect of Humidity on Wear of TiN Coatings: Role of Capillary Condensation

Metallurgical and Materials Transactions A - Coated ball-on-disk wear configuration was used to study the effect of relative humidity, water vapor pressure, and water on wear of TiN coatings in the...     

Tribological properties of modified jojoba oil as probable base stoke of engine lubricant

Journal of Mechanical Science and Technology - This paper investigates the tribological characteristics of modified jojoba oil (MJO) as a base stoke for SAE20W40 mineral oil (LO). In addition, a...     

Analyzing the characteristics of fuel extracted by catalytic conversion of waste engine oil

Production of hydrocarbon fuel from waste oil such as industrial and engine waste oil is an excellent way for producing alternating fuel sources. The aim of the present study is to obtain diesel-like fuel from waste engine oil (WEO) which can be used as an alternate fuel for compression ignition (CI) engine. With this aim in mind, WEO was purified from contaminants and thermally cracked with two different catalysts such as red mud and fly ash in a catalytic thermal reactor (CTR). The oil product obtained after catalytic conversion using red mud catalyst was named as WEORM and using fly ash catalyst was named as WEOFA. To investigate the influence of these two catalysts with WEO, different properties such as density, kinematic viscosity, calorific value, flash, and fire points were determined. Moreover, the compositional analyses for WEORM and WEOFA were analyzed by Fourier transform infrared (FT-IR) spectroscopy and gas chromatography–mass spectrometry (GC-MS). FT-IR spectroscopy revealed the presence of several bonds which appeared in WEORM and WEOFA were almost identical to the diesel fuel. Further FT-IR results confirmed that most of the hydrocarbons present in WEORM and WEOFA were alkanes. Furthermore, in GC-MS analysis, WEORM and WEOFA were mainly composed of C₁₀–C₃₀ hydrocarbons with the presence of aliphatic hydrocarbons and aromatics. Similar to fossil diesel fuel, they mainly contain paraffins, napthenese, and aromatics. Our results revealed that WEO can be effectively recycled and reused as an alternate source of hydrocarbon energy.     

Brazil’s new national policy on solid waste: challenges and opportunities

Brazil, one of the world’s largest developing countries, has recently introduced a new solid waste management regulatory policy. This new regulatory policy will have implications for a wide variety of stakeholders and sets the stage for opportunities and lessons to be learned. These issues are discussed in this article.     

Identification of Inverse Bainite in Fe-0.84C-1Cr-1Mn Hypereutectoid Low Alloy Steel

A unique dilatation trend is observed for isothermal bainite transformation in Fe-0.84 pct C-1 pct Cr-1 pct Mn steel. The dilatation is found to occur in two stages with volumetric contraction dominating the first stage, followed by volumetric expansion dominating the second stage. Through electron microscopic characterization, bainitic microstructure is identified as inverse bainite with cementite (Fe₃C) nucleating first from supersaturated austenite followed by the transformation of ferrite and secondary carbides (Fe₃C, Fe₂C, and Fe₅C₂) from carbon-depleted austenite.     

Optimization of Lithium Content and Sintering Aid for Maximized Li+ Conductivity and Density in Ta‐Doped Li7La3Zr2O12

Ta‐doped cubic phase Li₇La₃Zr₂O₁₂ (LLZ) lithium garnet received considerable attention in recent times as prospective electrolyte for all‐solid‐state lithium battery. Although the conductivity has been improved by stabilizing the cubic phase with the Ta⁵⁺ doping for Zr⁴⁺ in LLZ, the density of the pellet was found to be relatively poor with large amount of pores. In addition to the high Li⁺ conductivity, density is also an essential parameter for the successful application of LLZ as solid electrolyte membrane in all‐solid‐state lithium battery. Systematic investigations carried out through this work indicated that the optimal Li concentration of 6.4 (i.e., Li_6.4La₃Zr_1.4Ta_0.6O₁₂) is required to obtain phase pure, relatively dense and high Li⁺ conductive cubic phase in Li_7?xLa₃Zr_2?xTa_xO₁₂ solid solutions. Effort has been also made in this work to enhance the density and Li⁺ conductivity of Li_6.4La₃Zr_1.4Ta_0.6O₁₂ further through the Li₄SiO₄ addition. A maximized room‐temperature (33°C) total (bulk + grain boundary) Li⁺ conductivity of 3.7 × 10^?4 S/cm and maximized relative density of 94% was observed for Li_6.4La₃Zr_1.4Ta_0.6O₁₂ added with 1 wt% of Li₄SiO₄.