The performance of modified jatropha-based nanofluid during turning process

The industry's extensive use of petroleum-based metalworking fluid (MWF) harms the environment and humans. The production of bio-based MWF, especially from crude jatropha oil (CJO), has therefore taken numerous initiatives. This aimed to formulate newly modified jatropha oil (MJO) with the addition of 0.05wt.% hBN and 0.05wt.% MoS2 as the nanofluid for MWF. The performance of the nanofluids was determined through the turning process in terms of cutting temperature, workpiece surface roughness, tool life and tool wear of the tool lubricated by the nanofluids. The performance of the nanofluid samples was compared with the synthetic ester (SE). From the results, after conducted 100mm axial cutting length MJO+hBN+MoS2 recorded the lowest in cutting temperature and surface roughness compared to all samples. The result shows that MJO+hBN+MoS2 has longer tool life (6500mm) compared to SE (6000mm). Abrasion and adhesion were observed as the dominant tool wear mechanism. In conclusion, MJO+hBN+MoS2 shows better machining performance and has the potential to be an environmentally friendly metalworking fluid

Pengesan Optik, Piezoelektrik-fotoakustik

An optical detector based on piezoelectric detection of the photo acoustic effect in an absorbing metal plate is reported. Such a detector has been used in an experiment for measuring a Gaussian laser beam diameter using the knife-edge method. The responsivity of the detector varied from 4.05J.LV/mW at 68Hz to 1.25J.LV/mW at 211Hz. The Gaussian laser beam diameter obtained from the experimental data is (0.88 ± 0.02)mm and this value is comparable with the value stated in the laser specification note

ANTIBODY POLYCLONAL PRODUCTION ON RABBIT ANTI-OVINE PREGNANCY-ASSOCIATED GLYCOPROTEIN (Rabbit anti-ovPAG)

The aim of the study was to produce polyclonal antibody (rabbit anti-ovPAG) which could detect PAG in the urine of pregnant ewes. Twelve rabbits were immunized against ovPG DEAE-TrisHCl (DT), DEAE-NaCl 20mM (DN2), DEAE-NaCl 40mM (DN4), DEAE-NaCl 80mM (DN8), DEAE-NaCl 160mM (DN16), DEAE-NaCl 320mM (DN32) and DEAE-NaCl 1M (DN1) and NaCl 0.9 % as a placebo. The 0.5 ml of isolate (purified from ovine cotyledon) was emulsified in equal volume with complete and incomplete Freud’s adjuvant. The mixture of each isolate and adjuvant was injected at mutiple sites along the dorsal area of rabbits by subcutaneous route. Blood were collected from marginal ear vein, starting before first injection (baseline) and every 14 days. Rabbit anti-ovPAG were measured using Modified ELISA Technique. By using Western Blot Technique, DN32 showed the best immune response among others and also could differenciate ovPAG in the urine of pregnant ewes It could be concluded that ovPAG DN32 is a specific source of rabbit anti-ovPAG production. Protein of ovPAG at molecular weight 31 kDa is a pregnancy protein marker of garut sheep and could be developed as a major protein for producing antibodi

Thermal-induced nonlinearity of Ag Nano-Fluid prepared using y radiation method

The non-linear refractive index of Ag nano-fluids prepared by γ-radiation method was investigated using a single beam z-scan technique. Under CW 532 nm laser excitation with power output of 40 mW, the Ag nano-fluids showed a large thermal-induced non-linear refractive index. In the present work it was determined that the non-linear refractive index for Ag nano-fluids is -4.80×10-8 cm2/W. The value of Δn0 was calculated to be -2.05×10-4. Our measurements also confirmed that the non-linear phenomenon was caused by the self-defocusing process making them good candidates for non linear optical devices

Detection of dye molecules in solution using surface plasmon resonance technique

Surface plasmon resonance technique has been utilized as a sensitive optical sensor for detection of dye molecule in water. Three dye solutions were chosen for this study, such as methylene blue, rhodamine B and rhodamine 6G. All samples were prepared by dissolving dye powder in distilled water and the solution was diluted several times to produce sample solutions in the range of 0.001 to 0.01 mol/L. The shift of SPR angle (Δθspr) was monitored and characterized as sensor sensitivity and responsivity. The kinetic behaviour of the dye molecules was also discussed

Characterization of thermal, optical and carrier transport properties of porous silicon using the photoacoustic technique

In this work, the porous silicon layer was prepared by the electrochemical anodization etching process on n-type and p-type silicon wafers. The formation of the porous layer has been identified by photoluminescence and SEM measurements. The optical absorption,energy gap, carrier transport and thermal properties of n-type and p-type porous silicon layers were investigated by analyzing the experimental data from photoacoustic measurements. The values of thermal diffusivity, energy gap and carrier transport properties have been found to be porosity-dependent. The energy band gap of n-type and p-type porous silicon layers was higher than the energy band gap obtained for silicon substrate (1.11 eV). In the range of porosity (50–76%) of the studies, our results found that the optical band-gap energy of p-type porous silicon (1.80–2.00 eV) was higher than that of the n-type porous silicon layer (1.70–1.86 eV). The thermal diffusivity value of the n-type porous layer was found to be higher than that of the p-type and both were observed to increase linearly with increasing layer porosity

Friction and wear phenomena of vegetable oil based lubricants with additives at severe sliding wear conditions

The tribological responses of palm oil and soybean oil, combined with two commercial antiwear additives (zinc dialkyl dithiophosphate and boron compound), were investigated at a lubricant temperature of 100 °C and under severe contact conditions in a reciprocating sliding contact. The friction coefficient of palm oil with zinc dialkyl dithiophosphate was closest to the commercial mineral engine oil, with a 2% difference. The soybean oil with zinc dialkyl dithiophosphate produced a 57% improvement in wear resistance compared to its pure oil state. The existence of boron nitride in vegetable oils was only responsive in reduction of wear rather than friction. The response of commercial antiwear additives with vegetable oils showed a potential for the future improvement in the performance of vegetable oils