The main objective of this work is to propose a mathematical model for the differential sticking coefficient of clayey drilling fluids with a lubricant as an additive and evaluate the influence of differential pressure and lubricant content on filter cake thickness and permeability. Tests were carried out on fluids composed of water and 4.86% of active bentonite clay prepared in Hamilton Beach ...

This experimental study was carried out based on the nanotechnology approach to enhance efficacy of engine oil. Atomic and surface structures graphene oxide (GO) nanoparticles were investigated by using a field emission scanning electron microscope X-ray diffraction. The nano lubricant produced two-step method. stability analyzed through dynamic light scattering. Various properties such as ther...

Lubricant-impregnated surfaces (LIS), where micro/nanotextured surfaces are impregnated with lubricating liquids, have received significant attention for their robust, superslippery properties. In this study, we systematically demonstrate the potential for LIS to reduce drag in laminar flows. We present a scaling model that incorporates the viscosity of the lubricant and elucidates the dependen...

Highly ordered MoS2/Mo-S-C nanoperiod multilayers are synthesized by a novel self-assembling mechanism in simultaneous sputtering of MoS2 and graphite targets. The sequential formation of MoS2-riched domain layers and Mo-S-C compositional mixed capping layers reveals no correspondence to the sample stage rotation but is caused by the low energy ion bombardment enhanced interdiffusion. The HRTEM...

In the pharmaceutical industry is no longer worked without instrumented tablet presses. The recording of the press information at different parameters of each test series and batches in the development of tablets and an online measurement and control of pressing forces during the production process is becoming increasingly important. Eccentric tablet presses were equipped with sensors for the u...

abstract   background and aim: due to the increasing use of restorative materials, finding a  suitable material with low adhesion rate and colonization of pathogenic  streptococcus mutans has a significant importance. the purpose of this study was the  comparison of the adhesion rate of streptococcus mutans to “nano-hybrid composite” and “amalgam” at 1, 3, and 7 day  intervals. methods and mate...

Gold nanoparticles were synthesized using agarose as a reducing agent, which gelled to support the gold nanoparticles, then readily functioned as a template to produce a porous, evenly-distributed Au/TiO(2) nano-hybrid.

A new approach in the method of depositing an external lubricant on the die walls of a powder metallurgy press has been developed which allows the compaction of parts from mixes with no or minimal lubricant content. By heating the die to moderate temperatures (70°C 100°C) and using new composite lubricants, optimum thickness lubricant layers can be deposited allowing the compaction-ejection of ...

This paper presents the experimental research into the evaluation of lubricity for polyolester (POE) lubricant with HFC-134a refrigerant in rotary and reciprocating compressors for household refrigerators. In order to evaluate the lubricity for POE lubricant with HFC-134a refrigerant, we conducted 4-balls wear tests in the mixing environment of POE lubricant and HFC-134a refrigerant. In the pre...

Self-assembled supramolecular organization of nano-structured biomimetic light-harvesting modules inside solid-state nano-templates can be exploited to develop excellent light-harvesting materials for artificial photosynthetic devices. We present here a hybrid light-harvesting system mimicking the chlorosomal structures of the natural photosynthetic system using synthetic zinc chlorin units (Zn...