A substantial proportion of proven oil and gas reserves of the world is contained in the carbonate reservoir. It is estimated that about 60% of the world’s oil and 40% of gas reserves are confined in carbonate reservoirs. Exploration and development of hydrocarbons in carbonate reservoirs are much more challenging due to poor seismic imaging and reservoir heterogeneity caused by diagenetic changes. Evaluation of carbonate reservoirs has been a high priority for researchers and geoscientists working in the petroleum industry mainly due to the challenges presented by these highly heterogeneous reservoir rocks. It is essential for geoscientists, petrophysicists, and engineers to work together from initial phases of exploration and delineation of the pool through mature stages of production, to extract as much information as possible to produce maximum hydrocarbons from the field for the commercial viability of the project. In the absence of the well-log data, the properties are inferred from the inversion of seismic data alone. In oil and gas exploration and production industries, seismic inversion is proven as a tool for tracing the subsurface reservoir facies and their fluid contents. In this paper, seismic inversion demonstrates the understanding of lithology and includes the full band of frequency in our initial model to incorporate the detailed study about the basin for prospect evaluation. 3D seismic data along with the geological & petrophysical information and electrologs acquired from drilled wells are used for interpretation and inversion of seismic data to understand the reservoir geometry and facies variation including the distribution of intervening tight layers within the Miocene carbonate reservoir in the study area of Central Luconia. The out-come of the seismic post-stack inversion technique shows a better subsurface lithofacies and fluid distribution for delineation and detailed study of the reservoir.

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Due to environment and sustainability issues, it is important to reduce the use of petroleum based products in automotive and industrial application. One of the efforts is to use bio oils as base oil for lubricants. This paper presents the experimental results on the effects of palm methyl ester mixing in a conventional lubricant on the friction and wear characteristics of stainless steel SUS304. The friction tests were conducted using a ball-on-disk tribometer at boundary lubrication condition. Three kind of lubricants were prepared, i.e. commercial SAE40, and the mixture of 0.5% and 1% palm methyl ester into SAE40 lubricant. The prepared lubricants were designated as PME0, PME5, and PME10, in reference to 0%, 0.5%, and 1% palm methyl ester mixture in the SAE40 oil. Results shows that the addition of palm methyl ester in the lubricant has reduced the value of coefficient of friction from 0.7 to 0.55 with the addition of 1% palm methyl ester in the base lubricant. As for the wear, 10% reduction of the wear scar was achieved at the condition of PME10 compared to that at PME0. One of possible explanation for this reduction is the formation of oxidative layer on the contact interface due to the existence of the methyl ester in the lubricant. This result indicates the positive impact of the palm methyl ester as additive for enhancing the performance of conventional lubricant thus requiring further analysis and investigation.

The dielectric property in form of dielectric constant of material is a measure of material’s response to a given electric field. Electric fields induce conductive and polarizing currents based on their effect on free charge attached to biological material. This phenomenon occurs at all levels of organization including cellular, molecular and ionic. When the skin is exposed to ultraviolet radiation there will be a series of chain processes that cause emergence of Reactive Oxygen Species (ROS) in the tissue. Reactive Oxygen Species (ROS) in tissue will be very dangerous because it can cause damaging free radicals. Excessive exposure to UVA / UVB radiation causes various kinds of damage which affect the low dipole moment and polarity of cells that make up skin tissue. Dipole moment and low cell polarity will decrease the dielectric constant value of tissue which is triggered by presence of free radicals in form of singlet oxygen (1 O 2) and superoxide anion (O -* 2).