Laccase-assisted approach to graft multifunctional materials of interest: keratin-EC based novel composites and their characterisation

This study focuses on the evaluation of raw keratin as a potential material to develop composites with novel characteristics. Herein, we report a mild and eco-friendly fabrication of in-house extracted feather keratin-based novel enzyme assisted composites consisting of ethyl cellulose (EC) as a backbone material. A range of composites between keratin and EC using different keratin: EC ratios were prepared and characterised. Comparing keratin to the composites, the FT-IR peak at 1,630 cm-1 shifted to a lower wavenumber of 1,610 cm-1 in keratin-EC which typically indicates the involvement of β-sheet structures of the keratin during the graft formation process. SEM analysis revealed that the uniform dispersion of the keratin increases the area of keratin-EC contact which further contributes to the efficient functionality of the resulting composites. In comparison to the pristine keratin and EC, a clear shift in the XRD peaks was also observed at the specific region of 2-Theta values of keratin-g-EC. The thermo- mechanical properties of the composites reached their highest levels in comparison to the keratin which was too fragile to be measured for its mechanical properties. Considerable improvement in the water contact angle and surface tension properties was also recorded

African Linguistics in Central and Eastern Europe, and in the Nordic Countries

Non peer reviewe

Les urgences médicales au cabinet dentaire

BORDEAUX2-BU Sci.Homme/Odontol. (330632102) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

MPD Allows Operator to Safely and Efficiently Drill Challenging Wells In Kobes (Montney Formation) in British Columbia

Abstract Interest in the unconventional shale gas plays continues to grow in Western Canada. The Montney formation found in North Eastern British Columbia can be particularly challenging due to drilling in the Canadian Foothills. Wells in the area are known for deep, hard, abrasive and abnormally pressured formations. Further challenges include unexpected fractures, lost circulation and coals seams. The combination of these drilling issues can cause a significant increase in expected drilling times (slow ROP and NPT). Following some difficulty drilling offset wells due to well control issues, future designs incorporated a higher, more conservative mud weight. This let to slower ROP and corresponding NPT. A new approach with MPD and lighter mud weight was proposed. For the intermediate sections, the first well changed from a weighted to un-weighted invert emulsion. The second well was drilled with a pure base oil system to lower the fluids solids content. The horizontal section was initially planned to drill with a density of 1400kg/m3 weighted invert. A MPD program was proposed drilling with a 1250kg/m3 weighted invert for the next two wells and adjusting backpressure to match the required bottom hole ECD. The key operational objectives for the operator were increased ROP and a reduction of NPT. This was accomplished by lower ECD associated with lower mud densities, lower drilled solids and lower viscosities. A secondary benefit was the reduction of whole mud losses. Mud losses were reduced in manner that allowed for fast safe well control in the event a pressured fracture (kick) was encountered. A reduction of more than 7.4 days vs AFE from spud to rig release was largely attributed to utilizing MPD technique and the team work of everyone involved on location. NPT was reduced from 100 hours to 8 hours on the final well of the project. The second MPD well of the project was considered a big success, with the following results (refer table 1). Table 1 MPD2 vs Best Conventional well Performance Data Intermediate Hole Performance Main Hole Performance MPD#2 Well Best Conventional Well MPD#2 Well Best Conventional Well Bit Runs 3 4 3 8 Depth Length (m) 918 880 3080 2368 Time (hr) 41 77.5 243.75 290.3 ROP (m/hr) 26.5 11.55 11.3 8.025 As the activity in NE British Colombia's Montney play continues to grow, it is important that other operators learn the benefits of utilizing MPD. This includes safely decreasing days on the well by increasing ROP and reducing influx and losse related NPT caused by excessive mud weight.</jats:p

Valorisation des déchets ligno-cellulosiques pour la préparation d’un nouveau matériau composite PVC/farine des noyaux de dattes

Afin de limiter l’utilisation des énergies fossiles et de valoriser les déchets ligno-cellulosiques, les composites à fibres naturelles s’inscrivent dans un contexte favorable qui permettra de répondre à des enjeux environnementaux, économiques et sociaux grâce à leurs propriétés de faible coût, faible densité, renouvelables et de biodégradabilité. L’objectif de cette étude est de développer un nouveau matériau composite constitué d’une matrice thermoplastique, le polychlorure de vinyle (PVC), renforcée par des fibres naturelles à base des noyaux de dattes (FND) avec des taux de charge allant de 10 à 40 % massique. Différentes techniques d’analyses ont été utilisées pour étudier les propriétés mécaniques, morphologiques et la perméabilité d’eau des échantillons obtenus. Les résultats enregistrés indiquent que la contrainte à la rupture diminue avec l’augmentation du taux de charge en FND tandis que la rigidité augmente. L’analyse morphologique par microscopie électronique à balayage (MEB) montre une meilleure dispersion pour de faible taux de charge en FND. Une très faible absorption d’eau a été enregistrée.</jats:p