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The drawbacks of common anodes in lithium-ion batteries (LIBs) and hybrid supercapacitors (HSCs), such as the high voltage plateau of Li4Ti5O12 (1.55 V vs. Li/Li+) and the moderate capacity of graphite (372 mAh-g-1), have established a need for better materials. Conversion materials, and in particular iron oxide and CaFe2O4 (CFO), have amassed recent attention as potential anode replacements. In this study, we evaluate the material and electrochemical effects of the solution combustion synthesis (SCS) of porous CFO across novel fuel-to-oxidizer ratios and calcination temperatures. We demonstrate that nearly doubling the amount of fuel used during synthesis increases capacities between 120 and 150% at high current densities (~ 1000 mA-g-1) and across 500 additional charging-discharging cycles, an effect brought on in part by enhanced compositional purity in these samples. However, in order to ensure long-term cyclic stability, it is necessary to also calcine porous CFO to 900 °C to enhance crystallite size, particle size and spacing, and compositional purity. [ABSTRACT FROM AUTHOR]

Describes nature of school psychology programs and practices in Ghana, beginning with the historical development of practices during the period 1529-1971. Presents comparative analysis of past and contemporary school psychology practices. Discusses an examination of the system of school administration, professional education of teachers and psychologists, and services they provide. (Author/NB)

Relapse to substance abuse is a global problem and is conceptualized as an integral component of the recovery process. Global statistics on rates of relapse after substance abuse treatment are disturbingly high, averaging about 75% within a 3- to 6-month duration after treatment. This study sought to gain full understanding of the factors that precipitate relapse among substance abusers in Ghana. Data were collected through in-depth interviews with 15 relapsed substance abusers who were previously treated for substance abuse, and three mental health professionals at a psychiatric rehabilitation unit in Ghana. Findings showed that seven factors, including positive/negative emotional reinforcements, sense of loss, interpersonal conflicts, peer influence, familial, religio-cultural, and treatment-based issues complot to instigate and maintain the relapse cycle. The findings provide valuable insights into the relapse phenomenon in Ghana. Clinicians should actively engage family members in the relapse prevention process, and provide insight into religio-cultural relapse precipitants. [ABSTRACT FROM AUTHOR]

All-solid-state batteries (ASSBs) are gaining traction in the arena of energy storage due to their promising results in producing high energy density and long cycle life coupled with their capability of being safe. The key challenges facing ASSBs are low conductivity and slow charge transfer kinetics at the interface between the electrode and the solid electrolyte. Garnet solid-state electrolyte has shown promising results in improving the ion conductivity but still suffers from poor capacity retention and rate performance due to the interfacial resistance between the electrodes. To improve the interfacial resistance, we prepared a composite consisting of Li7La2.75Ca0.25Zr1.75Nb0.25O12 (LLCZN) garnet material as the ceramic, polyethylene oxide (PEO) as the polymer, and lithium hexafluorophosphate (LiPF6) as the salt. These compounds are mixed in a stoichiometric ratio and developed into a very thin disc-shaped solid electrolyte. The LLCZN provides a lithium-ion transport path to enhance the lithium-ion conduction during charging and discharging cycles, while the LiPF6 contributes more lithium ions via the transport path. The PEO matrix in the composite material aids in bonding the compounds together and creating a large contact area, thereby reducing the issue of large interfacial resistance. FESEM images show the porous nature of the electrolyte which promotes the movement of lithium ions through the electrolyte. The fabricated LLCZN/PEO/LiPF6 solid-state electrolyte shows outstanding electrochemical stability that remains at 130 mAh g−1 up to 150 charging and discharging cycles at 0.05 mA cm−2 current. All the specific capacities were calculated based on the mass of the cathode material (LiCoO2). In addition, the coin cell retains 85% discharge capacity up to 150 cycles with a Coulombic efficiency of approximately 98% and energy efficiency of 90% during the entire cycling process. [ABSTRACT FROM AUTHOR]