Two acylated chitosan Schiff base samples ACSB-1 and -2 were synthesized via a two-step reaction pathway. First the chitosan Schiff base (CSB) was prepared utilizing 3,5-di-tert-butyl-4-hydroxybenzaldehyde. In the second step, esterification with lauroyl chloride catalyzed by 4-(dimethylamino)pyridine (DMAP) in N,N-dimethylacetamide (DMAc) solvent affords the final product acylated chitosan Schiff base (ACSB-1 and -2). The products were identified and characterized by Fourier transform infrared (FT-IR) spectroscopy, CHN analysis, thermogravimetry (TG), X-ray diffraction (XRD), etc. The synthesized compounds were evaluated as multifunctional additives for antioxidant and lubricity properties in N-butyl palmitate/stearate. A rotating pressure vessel oxidation test (ASTM D2272) was used for evaluating antioxidant property. The thermo-oxidative stability of the N-butyl palmitate/stearate oil was increased 1.5 times by using this additive in 3000 ppm concentration of ACSB-2 at 150 °C. Lubricity property was evaluated by using the four ball test (ASTM D4172A) which was performed at 75 °C temperature, frequency of 1200 rpm, and 198 N load for 60 min. The lubricating efficiency of the synthesized sample was estimated by measuring the average wear scar diameter (WSD) of the spherical specimen. The WSD is also found to be decreased significantly by adding these compounds as additives in N-butyl palmitate/stearate. Both samples passed the copper strip corrosion test (ASTM D130) too.

Biodiesel is being promoted worldwide as a supplement and alternative automotive fuel for petroleum diesel in spite of several technological, economical and social barriers. This has provided an impetus for new research to overcome these deterrents in its production, to establish its quality criteria (standards), and to develop superior analytical methods for quality control and quality assessment of biodiesel in production and entire distribution chain until consumed by end user. The present review paper briefly covers the production, characterization and standardization of biodiesel, having relevance to the preparation of certified reference materials (CRMs) of biodiesel.

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Two novel triazine Schiff base-based cationic gemini surfactants namely N,N′-bis{(p-(N,N,N-tetradecyldimethylammonium bromide)-benzylidene} 6-methyl-1,3,5-triazine-2,4-diamine (14-MTR-14) and N,N′-bis{(p-(N,N,N-tetradecyldimethylammonium bromide)benzylidene} 6-phenyl-1,3,5-triazine-2,4-diamine (14-PTR-14) were synthesized following the twostep reaction. First the intermediate adduct was synthesized by reaction of the 4-(dimethylamino)benzaldehyde with 1-bromotetradecane. In the second step, the germinal surfactants 14-MTR-14 and 14-PTR-14 were synthesized by imine coupling with this intermediate adduct with 6-methyl-1,3,5-triazine-2,4diamine and 6-phenyl-1,3,5-triazine-2,4-diamine, respectively. Both were characterized using elemental analysis (CHN), infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and thermogravimetry (TG). The compounds were then evaluated as anticorrosive and lubricity improver additive in polyol lube base oil. Both the surfactants show the similar anticorrosive activities. The antiwear and antifriction characteristics were estimated in terms of average wear scar diameter (AWSD) and average friction coefficient using a four ball test following ASTM D4172B. It was found that the 14-MTR-14 is comparatively more effective than 14-PTR-14. 14-MTR-14 reduces the AWSD of the polyol from 690 to 575.83 μm while the average friction coefficient decreases from 0.110 to 0.082 at 4000 ppm doping concentration.

Two novel over based Ca salts of histidine schiff base estersCa-HDS-L and Ca-HDS-M were synthesized following three step 10 reaction. The histidine schiff base (HDS) was synthesized first by imine coupling of histidine with salicylaldehyde. Then its phenolic group was esterified using lauroyl chloride and myristoyl chloride to obtain the HDS-L and HDS-M respectively. Finally in the third step, their respective over based salts Ca-HDS-L and Ca-HDS-M 15 were synthesized by reaction with Ca(OH) 2 . All the synthesized compounds were characterized using the FT-IR, NMR, CHN and TG analysis. Panel coker federal test (FTM 3462), blotter spot test (ASTM D7899), universal oxidation test (IP-306) and four ball test (ASTM 4172A) were used for the evaluation of detergent,