With the currently strict environmental law in present days, researchers and industries are seeking to reduce the amount of cutting fluid used in machining. Minimum quantity lubrication is a potential alternative to reduce environmental impacts and overall process costs. This technique can substantially reduce cutting fluids in grinding, as well as provide better performance in relation to conventional cutting fluid application (abundant fluid flow). The present work aims to test the viability of minimum quantity lubrication (with and without water) in grinding of advanced ceramics, when compared to conventional method (abundant fluid flow). Measured output variables were grinding power, surface roughness, roundness errors and wheel wear, as well as scanning electron micrographs. The results show that minimum quantity lubrication with water (1:1) was superior to conventional lubrication-cooling in terms of surface quality, also reducing wheel wear, when compared to the other methods tested.

MQL technique is considered as a cleaner machining compared to the conventional coolant delivery one, thereby ensuring environmental sustainability and economic benefits. However, one of problems commonly reported when using the MQL technique is the wheel clogging phenomenon as a result of the inefficient chip removal from the cutting zone, then the chips lodge inside the pores of the grinding wheel, adversely affecting the quality and the finishing of the final product. In this context, this study was carried out to evaluate the performance of the minimum quantity lubrication coolant technique assisted with a wheel cleaning jet (MQL + WCJ) in plunge grinding of hardened steel. This cooling-lubrication technique was tested using the following flow rates: 30, 60, and 120 ml/h. Comparative tests were also carried out with the conventional coolant technique, as well as with the traditional MQL technique (without the wheel cleaning jet). The output variables used to assess the efficiency of the MQL + WCJ technique are roughness, roundness, workpiece microhardness, grinding wheel wear, and power consumption. The results showed that the machining with the MQL + WCJ technique outperformed the traditional MQL technique in all the output parameters investigated. Also, the efficiency of the MQL + WCJ technique increased with flow rate, thereby being an alternative coolant delivery technique in grinding due to cleaner environment, more sustainable and lower consumption of fluid compared to conventional coolant one. No thermal damages and cracks on the machined surface and sub-surfaces were observed after grinding AISI 4340 steel, irrespective of the technique.

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Incorporation of the histone deacetylase (HDAC) inhibitor, suberoylanilide hydroxamic acid (SAHA), to a culture broth of the endophytic fungus Phoma sp. nov. LG0217 isolated from Parkinsonia microphylla changed its metabolite profile and resulted in the production of (10 0 S)-verruculide B (1), vermistatin (2) and dihydrovermistatin (3). When cultured in the absence of the epigenetic modifier, it produced a new metabolite, (S,Z)-5-(3 0 ,4 0-dihydroxybutyldiene)-3-propylfuran-2(5H)-one (4) together with nafuredin (5). The structure of 4 was elucidated by spectroscopic analyses and its absolute configuration was determined by application of the modified Mosher's ester method. The absolute structure of (10 0 S)-verruculide B was determined as 5-[(10 0 S,2 0 E,6 0 E)-10 0 ,11 0-dihydroxy-3 0 ,7 0 ,11 0-trimethyldodeca-2 0 ,6 0-dien-1 0yl]-(3R)-6,8-dihydroxy-3-methylisochroman-1-one (1) with the help of CD and NOE data. Compound 1 inhibited the activity of protein tyrosine phosphatases (PTPs) 1B (PTP1B), Src homology 2-containing PTP 1 (SHP1) and T-cell PTP (TCPTP) with IC 50 values of 13.7 ± 3.4, 8.8 ± 0.6, and 16.6 ± 3.8 lM, respectively. Significance of these activities and observed modest selectivity of 1 for SHP1 over PTP1B and TCPTP is discussed.

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Minimum quantity of lubricant (MQL) in grinding is an alternative for reducing abundant fluid flow and both environmental and health hazards when compared with conventional fluid application. In spite of the fact that MQL is considered an innovative cost-effective and environmentally friendly technique, when used in grinding its inadequate application can increase cutting temperature and wheel clogging, worsening surface roughness, and increasing geometric and dimensional errors. The present study aims to evaluate improvements in MQL in grinding using MQL + water (1:1, 1:3, and 1:5 parts of oil per parts of water), when compared to MQL without water and conventional cooling-lubrication technique. Wheel cleaning by compressed air was also tested, aimed for unclogging of the wheel pores. The tests were performed in a plunge cylindrical grinder with CBN wheel and workpieces of AISI 4340 for different feed rates. The ground workpieces were analyzed with respect to the surface roughness, roundness errors, microhardness, and microscopic changes. In addition, tangential cutting force and diametric wheel wear were investigated. The results observed for the MQL plus water in the proportion of 1:5, with wheel cleaning system (at 30° inclination angle of the air nozzle) were the best, when compared to MQL without water, and close to the conventional flood coolant, implying that this technique is a potential alternative for cooling-lubrication when applied properly

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