The accumulation of pollutants in water is dangerous for the environment and human lives. Some of them are considered as persistent organic pollutants (POPs) that cannot be eliminated from wastewater effluent. Thus, many researchers have devoted their efforts to improving the existing technology or providing an alternative strategy to solve this environmental problem. One of the attractive materials for this purpose are metal-organic frameworks (MOFs) due to their superior high surface area, high porosity, and the tunable features of their structures and function. This review provides an up-to-date and comprehensive description of MOFs and their crucial role as adsorbent, catalyst, and membrane in wastewater treatment. This study also highlighted several strategies to improve their capability to remove pollutants from water effluent.

Ferritic steel is a potential metal candidate for interconnect solid oxide fuel cell (SOFC) because its ability to form chromia layer at the surface during high temperature operation. However, chromia based oxide scales is reluctant to the evaporation of Cr from the oxide–gas interface. In this work, a combination of titanium alloying and application of Co₃O₄ spinel coating using dip coating method are carried out to improve the performance of ferritic steels as SOFC interconnect. The oxidation behavior of coated and uncoated Fe-20wt.%Cr alloys with different titanium contents: 0, 0.5, and 1 wt.% are studied as a function of time in air atmosphere. The samples were isothermally oxidized at 800°C for 24, 48, and 96 h in a box furnace. Preoxidation experiment were carried out on the alloys before the application of Co₃O₄ coating to improve its adherence. X-ray diffraction analysis (XRD) and Scanning Electron Microscope (SEM) were used for characterization of the prepared samples. The results shows that increasing the concentration of titanium in the alloys both for coated and uncoated samples caused the increased oxidation rates. The oxidation resistance of Co₃O₄ coated samples indicated from the weight change measurement was larger than that of the uncoated samples. Co₃O₄ coating is not effective for improving the oxidation resistance of samples.

Tool steel is commonly used as punch & dies to form and cut AHSS (Advanced High Strength Steel) in the process of making car frames and bodies. Due to the high strength value of AHSS steel, it often results in damage to punch & dies. There are general techniques such as adding and changing the composition, heat treatment, coating techniques, using lubricants, or combining them all to increase the lifetime of the punch & dies itself. The development of alternative methods is the target of current studies. Recently, other methods used on Hadfield Steel to increase hardness and wear resistance, by utilizing a strain hardening mechanism, when the steel is repeatedly hit (repetitive hammering). The focus of this research is to observe the effect of heat treatment and hardening strain on the microstructure, hardness, and strain value of tool steel. Observations and characterizations using OES, metallographic and hardness tests have been carried out to determine the chemical composition, microstructure and hardness value. Quenched and tempered samples were repetitively hammered to see the behaviour of tool steels on strain, hardness, and microstructure.

In this work, Cr-ZrO₂ composite coating were prepared by electrodeposition method on aluminium substrate from chromic acid based electrolytes containing gelatin. The effect of gelatin on the corrosion resistance of Cr-ZrO₂ coatings were studied in 3 wt.% sodium chloride solutions. Potentiodynamic polarization studies were performed using a Versastat 3 (Princeton Applied Research) electrochemical system with a three-electrode cell. Results shows that the corrosion resistance of Cr-ZrO₂ coating on Al substrate was improved by the addition of gelatin to the coating solution. The addition of gelatin shifted the potentiodynamic polarization curved in the noble direction. The corrosion potential changed positively from -778 mV to -259 mV. The corrosion rate of Cr-ZrO₂ coating decreased from 4.44±0.93 mpy to 0.13±0.01 mpy with the addition of 3g/L gelatin.

Various species of Bamboo is widely available in Indonesia. Usually it is used as pillars, roof frame, and for walls in a woven form and it can be used for steel substitute in reinforced concrete. In making bamboo as a strengtheners or reinforcement a proper volume fraction should be chosen. Besides that, the minimum distance between bamboo bars or inter-strengtheners distance must be determined so that the reinforcement effect on cement matrix takes place. Ten variations of mixtures were used in this research. The number and distance between reinforce bars and its arrangement perpendicular or parallel with loading direction. From the observation it is found that both of the vertically and horizontally arranged bamboo bars at minimum inter-strengtheners distance of 10 mm gave maximum reinforcement and the flexural strength are 16.1 ± 0.3 MPa and 15.8 ± 0.6 MPa. Whereas cement only sample gave 7.2 ± 0.6 MPa hence 2 folds increase. For distance less than 10 mm, the flexural strength is lower, even volume fraction is relatively high and it supposed to give higher strength, in fact this is due to composite reinforcement effect did not occur and this is belief due to a hindered hydration process.