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Coal, which reserve is still abundant, can be a vital primary energy source in Indonesia in the coming decade to substitute oil and gas. The oil and gas reserves has nearly depleted but they have not been compensated by other new and renewable energy sources. However, coal as a solid fuel cannot be used as versatile as liquid fuel, especially for transportation fuel. Therefore, it is important to study the coal liquefaction technology in order to substitute the petroleum based liquid fuel. Among other technologies, solvent coal liquefaction has an interesting potential since it usually employs moderate operating conditions and does not require as much hydrogen supply as other technologies. From this review, we found that the choice of solvent is important factor in coal liquefaction. Solvent polarity will affect the yield and the product composition. Another important factor is operating temperature. The solvent liquefaction rate will increase if the operating temperature is closer to the coal softening temperature. In the coal liquefaction process, coal particle size can be an essential element. Depending on the initial size, the particle may remain intact or may completely dissolved during the process, therefore it will significantly affect the extraction rate. [ABSTRACT FROM AUTHOR]

In this article, an augmented reality application interface was developed, using a technological tool oriented towards teaching-learning that allows a mobile manipulator robot training system to be created. Focusing on the simulation of autonomous control algorithms and the implementation of animations made in the Unity 3D software, which will allow the user to interact with the real world through a mobile device where the rear camera will used to capture the image and the touch screen for visualization. It is verified that the application is intuitive and understandable for the user to operate, in order to provide the necessary knowledge of the operation and structure of the robot. [ABSTRACT FROM AUTHOR]

A preliminary investigation was conducted into the feasibility of using simple mechanical properties experiments to evaluate interstitial impurity uptake from processing environments. Two types of tests were examined: tensile tests and complex modulus measurements using a dynamic mechanical analyzer (DMA). For the tensile tests, samples were cut from a single crystal of niobium, with the same orientation, and then prepared following different procedures. Significant differences were observed during tensile tests, with yielding strength and strain-to-failure clearly related to interstitial uptake. When the strain rate was reduced by an order of magnitude, the strain-to-failure was reduced by 18% indicating that interstitial hydrogen is responsible for this behavior. For the complex modulus measurement, polycrystalline samples from different locations of two different ingots were examined at a frequency of 1.0 Hz while the temperature was increased at the rate of 1.0 °C per minute. Anaelastic peaks were found for C, N, and O in all samples, but the lower limit of the system did not allow for detection of a peak for H. It is concluded that mechanical properties could be developed as a measurement tool to guide the development of processing methods for producing reduced interstitial content material, but additional research, and uncertainty analysis, is required for these tools to be reliable in this application. [ABSTRACT FROM AUTHOR]