Quaid-i-Azam University

About: Quaid-i-Azam University is a education organization based out in Islamabad, Pakistan. It is known for research contribution in the topics: Heat transfer & Nanofluid. The organization has 6577 authors who have published 16865 publications receiving 381678 citations. The organization is also known as: Islamabad University.

Microbial degradation of aliphatic and aliphatic-aromatic co-polyesters

Abstract: Biodegradable plastics (BPs) have attracted much attention since more than a decade because they can easily be degraded by microorganisms in the environment. The development of aliphatic-aromatic co-polyesters has combined excellent mechanical properties with biodegradability and an ideal replacement for the conventional nondegradable thermoplastics. The microorganisms degrading these polyesters are widely distributed in various environments. Although various aliphatic, aromatic, and aliphatic-aromatic co-polyester-degrading microorganisms and their enzymes have been studied and characterized, there are still many groups of microorganisms and enzymes with varying properties awaiting various applications. In this review, we have reported some new microorganisms and their enzymes which could degrade various aliphatic, aromatic, as well as aliphatic-aromatic co-polyesters like poly(butylene succinate) (PBS), poly(butylene succinate)-co-(butylene adipate) (PBSA), poly(e-caprolactone) (PCL), poly(ethylene succinate) (PES), poly(L-lactic acid) (PLA), poly(3-hydroxybutyrate) and poly(3-hydoxybutyrate-co-3-hydroxyvalterate) (PHB/PHBV), poly(ethylene terephthalate) (PET), poly(butylene terephthalate) (PBT), poly(butylene adipate-co-terephthalate (PBAT), poly(butylene succinate-co-terephthalate) (PBST), and poly(butylene succinate/terephthalate/isophthalate)-co-(lactate) (PBSTIL). The mechanism of degradation of aliphatic as well as aliphatic-aromatic co-polyesters has also been discussed. The degradation ability of microorganisms against various polyesters might be useful for the treatment and recycling of biodegradable wastes or bioremediation of the polyester-contaminated environments.

Foam–like Co9S8/Ni3S2 heterostructure nanowire arrays for efficient bifunctional overall water–splitting

Abstract: Foam–like nanowire arrays composed of the Co9S8/Ni3S2 heterostructure possess huge electrochemical surface areas and rich lattice defects. The value of double–layer capacitance for Co9S8/Ni3S2 is detected to be 81.4 m F·cm−2, which is four times more than the precursor (NixCo1-x(CO3)0.5OH). This enhancement greatly produces a large number of catalytic reaction sites for contacting with electrolyte ions. The method of in–situ vulcanization growth urges the uniform distribution of Co9S8 and Ni3S2, forming a large number of lattice defects in the heterointerfaces. These lattice defects modulate the local electronic arrangement to become the most active reaction sites. Density functional theory calculations demonstrate that the defective heterointerfaces are beneficial to the chemisorption of H+ and OH–. Electrochemical tests illustrate that Co9S8/Ni3S2 electrodes exhibit efficient activities for oxygen and hydrogen evolution reactions and have remarkable stabilities in alkaline solution for commercial application.