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We recommend best practices for the recovery of cobalt from LiCoO2 (LCO) lithium-ion battery (LIB) cathodes by (i) leaching using green deep eutectic solvents (DES) and (ii) subsequent electrodeposition, through a case study of the choline chloride (ChCl):ethylene glycol (EG) DES. DES physical properties (conductivity, viscosity, and surface tension) were tailored by varying the composition between mole ratios of 1:2 and 1:5 (ChCl:EG). Examined along with leaching process parameters (temperature, duration), increasing the fraction of hydrogen bond donors (HBDs) decreased DES surface tension and enhanced leaching. Complete Co recovery was achieved using 1:5 ChCl:EG DES at 160oC and 48 hours. Leaching temperatures >160oC are discouraged due to DES thermal degradation. The electrodeposition process was optimized for selective Co recovery with high faradaic efficiency.  The leaching ability of the DES was antithetical to the stability of electrodeposition cell components and required operational parameter adjustment to minimize degradation. The optimized system (copper cathode and stainless-steel anode) employing 1:5 DES leachate exhibited a faradaic efficiency of ~80 %, specific Co recovery of ~0.8 mg hr-1 cm-1 at 50 oC and evidence of uniform deposition. DES surface tension is a key descriptor of metal recovery, and guidelines are presented to maximize selective Co recovery.

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Co3O4-impregnated NiO-YSZ (yttria-stabilized zirconia) is a possible electrocatalyst for direct methane electrooxidation with both high catalytic activity and the ability to mitigate coking. The physical and electrochemical properties of Co3O4-impregnated NiO-YSZ anodes are investigated and benchmarked against NiO-YSZ and CeO2-impregnated NiO-YSZ anodes. The following methane electrooxidation activity trend: Co3O4-impregnated NiO-YSZ > CeO2-impregnated NiO-YSZ > NiO-YSZ with io (exchange current density) values of 88, 83, and 2 mA cm-2, respectively, is obtained in the high overpotential region. The high activity of Co3O4-impregnated NiO-YSZ is attributed to the changes in the electronic structure and microstructure with the incorporation of nickel into the lattice of Co3O4 as observed using X-ray photoelectron spectroscopy, temperature-programmed reduction, high-resolution transmission electron microscopy, and field emission scanning electron microscopy. Co3O4-impregnated NiO-YSZ also demonstrated the least coking during operation, confirming its utility as a methane electrooxidation catalyst.

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Maxillo Mandibular injuries are most common through road traffic accident. The defects and deformities are usually prominent in case of facial injuries. The ultimate aim of recontouring and reconstruction of the facial defect is to achieve the maximum functional as well as esthetic part of the face. Here we present a case of fracture in to multiple fragment of the infra orbital rim, reconstructed with rib graft.

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BACKGROUND/AIMS: Colorectal cancer (CRC) is the most frequent cancer and a leading cause of cancer death in the Kingdom of Saudi Arabia (KSA). To date, no nationwide screening programs have been adopted. This prospective, longitudinal study investigated factors influencing the outcome of CRC in Saudi patients. METHODS: Patients completed a CRC awareness questionnaire. Colonoscopy, CT/MRI, histopathology of tumor biopsies, and KRAS and BRAF testing were performed. Patients were treated according to their stage. All patients were followed until the end of the study and 3- and 5-year survival was assessed. RESULTS: Sixty percent of study patients with sporadic CRC presented with significantly advanced disease (stages III and IV) with or without metastases at entry. Patients showed low levels of awareness of the risk factors and signs of CRC. Patients presented at a median age of 50 years. Family history of CRC and ulcerative colitis were positive in 11 and 6% of patients, respectively. Stage III/IV tumors with distant metastases at enrollment, right-sided tumors, mucinous tumors, lymphovascular invasion, and KRAS (51%) or BRAF (28%) mutations predicted poor prognosis and survival. CONCLUSION: CRC in KSA is usually diagnosed at advanced stages with metastases and KRAS/BRAF, and is associated with poor prognosis and short survival. Nationwide awareness campaigns and screening programs for CRC are critical for prevention, early detection and adequate management of CRC.

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