ABSTRACT
A systematic study on the electrochemical reforming of monosaccharides (fructose, glucose, and xylose) using Pt-based anodic electrocatalysts is here presented for the first time to completely optimize the anodic catalyst and electrolyzer operating conditions. First, the electro-oxidation of each molecule was studied using a monometallic (Pt) and two bimetallic (PtNi and PtCo) anodic electrocatalysts supported on graphene nanoplatelets (GNPs). Tests in a three-electrode cell showed superior electrochemical activity and durability of PtNi/GNPs, especially at potentials higher than 1.2 V vs RHE, with the highest electrocatalytic activity in d-xylose electro-oxidation. Then, monometallic (Pt and Ni) and bimetallic electrocatalysts with different Pt:Ni mass ratios (1:1 and 2:1) were studied for d-xylose electro-oxidation, with the 2:1 mass ratio presenting the best results. This electrocatalyst was selected as the most suitable for scale-up to an anion-exchange membrane electrolyzer, where the optimal operating potential was determined. Additionally, stable operating conditions of the electrolyzer were achieved by cyclic H2 production and cathodic regeneration polarization steps. This led to suitable and reproducible H2 production rates throughout the production cycles for renewable hydrogen production from biomass-derived streams.
ABSTRACT
The aim of this study was to examine the possibility of complications in medial meniscus repair using an inside-out suturing device. Anatomical cadaveric study. Six fresh frozen cadaveric lower limbs were used. The posterior horn of the medial meniscus was sutured using three vertical stitches. An anatomical dissection was subsequently performed to check for any possible effects upon the structures of the medial aspect of the knee. In addition, an incision was made in a safety zone in order to ascertain whether it was possible to carry out the suture without affecting the aforementioned structures. No vascular or nervous structures were pierced by the needle. On knotting, it was found that a number of different structures had become trapped: the sartorial tendon was affected in each of the specimens used. In four cases, the saphenous vein was trapped by some of the knots. The saphenous nerve was trapped in four instances. Once this had been established, a small accessory incision was made to provide access to a safety zone, where suture can be performed without affecting any neurovascular or tendinous structures. Inside-out suture of the posterior meniscal horn carries a high incidence of entrapment of the neurovascular structures of the medial aspect of the knee. The sartorial tendon is constantly affected. Such complications can easily be avoided by entering the safety zone via a small auxiliary incision. This study provides evidence that complications affecting the peripheral structures of the medial aspect of the knee may arise during inside-out suture of the posterior horn of the medial meniscus and proposes a simple method of averting them.
