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•Biodiesel production from palm and kernel oil via transesterification by lipase.•Use of Response Surface (RSCCD) of Design Expert Software to optimize production.•Produced biodiesel properties conformed to American and European standards.

The ductility and hardness of AA6011/SiCpcomposites using NaCl, SnCl2, NH4Cl and PdCl2as wetting reagents were investigated. SiCpwas cleaned with the wetting reagents, and used as reinforcement in AA6011 alloy using the stir casting method. Ductility and hardness responses of the composites were measured using standard methods. Microstructural features were examined using scanning electron microscopy and the phases were determined with the help of an X-ray diffractometer. The results show that for all wetting agents, the increase in cleaning time leads to initial increase in ductility to a certain value, but a decrease afterwards with further increase in cleaning time. The best combination of hardness (BHN 57.88) and ductility (11.91%) was shown under conditions of 40 g/L SnCl2and cleaning time of 60 min. A minor formation of Al4C3was noted in diffraction patterns, indicating that the formation of deleterious precipitate was hindered by the cleaning process.

Thermal characteristics of processed macro-fibres from five agricultural wastes have been studied. Cellulosic fibres for composite applications are extracted from groundnut shell, coconut shell, rice husk, palm bunch and palm stalk using two paths (M1 and M2) and characterised for improvement in thermal behaviour. Thermal degradation and stability of the processed fibres are characterised using thermo gravimetric analysis and differential scanning calorimetry (DSC). Results show that M2-treated fibres generally possess higher heats of dehydration than M1-treated fibres and this is an indication of superior thermal behaviour of M2-treated fibres. Differential thermal gravimetry curves show that M2-processed fibres contain higher percentage of cellulose content than M1, which shows the removal of lignin and hemicellulose during degradation. Decomposition activation energy of fibres confirms that M1 fibres require higher activation energy for decomposition than M2. Higher degradation temperature is noted for M1-treated fibres than M2-treated fibres.

Plastic deformation process resulting in ultra fine grained materials which are rapidly grasping applications due to their superior mechanical properties remain an area of continued research interest. Generally, the influence of die land length and web to flange ratio in grain refinement subsequent to plastic deformation process have not being adequately exploited especially in complex die opening geometries. In the present study, the effect of these parameters on extrusion pressure and morphological change in I-shaped die opening geometry is investigated and reported. A forward extrusion rig is designed and manufactured for the purpose of experimental investigation. The upper bound analysis shows that increasing die land length leads to increasing relative extrusion pressure. Optimum web to flange ratio of 0.45 is numerically simulated and recommended to extrude I-shaped lead alloy with minimum load requirement. The experimental results reveal that increasing area ratio leads to quasi-sinusoidal pattern in surface hardness of I-shaped section irrespective of strain rate value. Increasing web to flange ratio, therefore, leads to increasing anisotropy of the I-shaped lead alloy. The extruded sections were examined with optical metallurgical microscope, and it is observed that increasing strain rate results in profound refinement of grain and inclusions in lead alloy even at room temperature.

Background: Guidelines for initiating renal replacement therapy (RRT) are based on renal function and not age, so renal function at onset of RRT is expected to be similar across age groups. Aim: To evaluate renal function at initiation of RRT across age groups. Design: Observational cross-sectional study. Methods: We extracted data for all incident chronic kidney disease (CKD) stage 5 patients (n = 322 064) commenced on chronic dialysis (haemodialysis and peritoneal) and renal transplant in the US from 1995 to 1999 from the US Renal Data Systems (USRDS). Subjects (n = 662) with incomplete data were excluded. The reminder (n = 321 402) were classified into five age groups: 0–19 years; 20–44 years; 45–64 years; 65–74 years; 75 years. Mean values of serum creatinine (Cr, mg/dl), creatinine clearance (CrCl, ml/min), body weight (kg) and body mass index (BMI, kg/m2) at onset of RRT were computed. Mean daily urinary creatinine excretion per kg body weight (CrCl × Cr/0.07/weight) was also calculated. Results: Progressively lower serum creatinine levels were found in adult patients with increasing age (10.70, 8.56, 7.38 and 6.88 mg/dl in those aged 20–44 years, 45–64 years, 65–74 years, 75 years, respectively). CrCl was also lower in the same groups (14.76, 13.38, 11.63 and 11.60 ml/min, respectively). Discussion: Older patients have a greater reduction in renal function than younger patients at onset of RRT, suggesting a delay in initiation of therapy.