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The prospect of decoupling economic development from CO2 emissions in Ghana is examined in this paper, with an emphasis on the manufacturing, export, and adoption of renewable energy sectors. The paper investigates the long-term and short-term correlations among CO2 emissions, renewable energy consumption (RNE), population growth (POP), manufacturing value-added (MVA), Economic growth (GDP), and exports (EXP) using an Autoregressive Distributed Lag (ARDL) bounds testing method using time series data from 1990 to 2020. The outcomes show that the variables are long-term cointegrating. Long-term GDP and CO2 emissions show a positive but negligible correlation, whereas exports show a negative and insignificant correlation. In the near term, using renewable energy has a markedly undesirable consequence on releases, yet, over time, the connection is positive and negligible. Because the turning point when economic expansion results in lower emissions is not apparent, the Environmental Kuznets Curve concept is not entirely substantiated. The report emphasizes how specific laws encouraging the use of renewable energy, environmentally friendly export and manufacturing processes, and technical advancements are necessary to help Ghana move toward a low-carbon economy.

A new study investigates the use of Nd3+-doped fluoroaluminate glass as an alternative for a low-cost 1.3 mu amplifier device.

Research was conducted to examine the effects of the site symmetry and host polarizability on the hypersensitive transition (super 3)P(sub 0) -> (super 3)F(sub 2) of Pr3+ in fluoride glasses. A comparison of the data in fluoride families and the date on the selected tellurite and sulfide glasses was performed. Results show that the (super 3)P(sub 0) -> (super 3)F(sub 2) transition of Pr3+ in fluoride glasses hosts is hypersensitive. The effect of ligand (glass host) polarizability on this hypersensitive transition within fluoride glass families was also demonstrated.

East African lakes support the food and water security of millions of people. Yet, a lack of continuous long-term water quality data for these waterbodies impedes their sustainable management. While satellite-based water quality retrieval methods have been developed for lakes globally, African lakes are typically underrepresented in training data, limiting the applicability of existing methods to the region. Hence, this study aimed to (1) assess the accuracy of existing and newly developed water quality band algorithms for East African lakes and (2) make satellite-derived water quality information easily accessible through a Google Earth Engine application (app), named LAndsat water QUality retrieval tool for east African lakes (LAQUA). We collated a dataset of existing and newly collected in situ surface water quality samples from seven lakes to develop and test Landsat water quality retrieval models. Twenty-one published algorithms were evaluated and compared with newly developed linear and quadratic regression models, to determine the most suitable Landsat band algorithms for chlorophyll-a, total suspended solids (TSS), and Secchi disk depth (SDD) for East African lakes. The three-band algorithm, parameterised using data for East African lakes, proved the most suitable for chlorophyll-a retrieval (R2 = 0.717, p < 0.001, RMSE = 22.917 μg/L), a novel index developed in this study, the Modified Suspended Matter Index (MSMI), was the most accurate for TSS retrieval (R2 = 0.822, p < 0.001, RMSE = 9.006 mg/L), and an existing global model was the most accurate for SDD estimation (R2 = 0.933, p < 0.001, RMSE = 0.073 m). The LAQUA app we developed provides easy access to the best performing retrieval models, facilitating the use of water quality information for management and evidence-informed policy making for East African lakes.

Terahertz (THz) time-domain transmission spectroscopy was used to obtain the absorption coefficients and refractive indices of silica, Pyrex, and seven different Schott glasses. The refractive indices were analyzed using the Clausius–Mossotti equation, and the absorption coefficients in terms of the power-law model of far-infrared absorption. Relationships were observed between THz absorption and refractive indices on the one hand, and glass properties on the other. THz transmission data have been shown to provide a useful insight into glass structure. [ABSTRACT FROM AUTHOR]

The relaxation time and absorption and emission profiles of the 0.59 THz TO phonon resonance in a ε-GaSe single crystal were measured using terahertz free induction decay, observed directly as a sequence of decaying sinusoidal oscillations in the time-domain signal following single-cycle pulse excitation. The phonon line profile was also measured using frequency-domain transmission with the resolution of 0.25 GHz and was found to be Lorentzian. [ABSTRACT FROM AUTHOR]