Economic Growth and Electricity Consumption in a Multivariate Framework: A Case of Zimbabwe 1980 to 2016

Electricity is important for sustainable development as it enhances productivity, employment and general living standards of people. The paper investigates the relationship between electricity consumption and economic growth in a multivariate framework for the period 1980 to 2016 in Zimbabwe. The study builds on previous bi-variate studies on electricity consumption and economic growth nexus. Specifically, the study applies both granger causality tests and single step error correction model to study the relationship between electricity consumption, economic growth and investment. The Granger causality tests confirm the existence of a bi-directional causality between electricity consumption and economic growth. This implies that in Zimbabwe, electricity growth results in increased economic growth and vice versa. Electricity also granger causes investment in Zimbabwe. The study shows that there is a long run relationship between electricity, investment and economic growth in Zimbabwe. The results suggest that consumption of electricity is a prerequisite and a binding constraint to achieving higher economic growth in Zimbabwe. In order to boost economic growth, the country needs to profoundly invest in electricity infrastructure.&nbsp

Composite carbon materials from winery composted waste for the treatment of effluents contaminated with ketoprofen and 2-nitrophenol

The present work consisted of preparing and characterizing composite carbon materials (WRCC) from raw winery residues (WR) activated with zinc chloride to produce a carbon adsorbent. The WRCC was used for the adsorption of emerging contaminants in aqueous media. The WRCC presented a morphology with favorable characteristics for the adsorption process, giving an abundant porous structure with pores of different sizes. The results show the WRCC's effectiveness, presenting surface area values (227 m2 g-1) and total pore volume (0.175 cm3 g-1). The general order kinetic model predicted the experimental curves sufficiently. The Sips model better described the two adsorbates' equilibrium data, with maximum adsorption capacities of 376.0 and 119.6 mg g-1 for 2-nitrophenol and ketoprofen, respectively. The WRCC carbon material was also highly efficient, with maximum removal of 81.4% and 94% in 1000 mg L-1 of the compounds 2-nitrophenol and ketoprofen. Finally, the prepared material has essential characteristics that make it an efficient adsorbent in treating effluents with emerging contaminants

Firm-size and wages: a case study of the manufacturing sector in Zimbabwe

It has long been argued in the mainstream literature that workers in large firms earn higher wages than those in smaller firms. This phenomenon is recognised as an important puzzle that explains wage disparities in labour markets. This thesis analyses the link between firm size and wages in the Zimbabwean manufacturing sector and it is structured around three main research questions: (1) What is the link between firm size and wages in the formal and informal manufacturing sector in Zimbabwe? (2) Is there a firm-size wage premium in the formal and informal manufacturing sector in Zimbabwe? (3) If yes, what are the sources of the firm-size wage premium? The analysis of the study draws on the Matched Employer-Employee manufacturing firm-level survey dataset for formal and informal sector firms and workers that was collected in 2015. Using this dataset, we are able to distinguish between theories that attribute wage disparities to worker heterogeneity and those that hypothesise the importance of firm heterogeneity, which advances the existing literature by including the informal sector and a developing country case. We then apply the Mincerian wage regression approach to determine the magnitude, significance, and sources, of the firm size-wage premium. We control for a variety of human capital, individual, job, and firm characteristics to determine the source of the firm size wage relationship. The empirical results indicate a positive and significant association between firm size and wages in both the formal and informal sectors, as theoretically expected. The firm-size premium is more nuanced in the informal sector. Human capital endowments are found to contribute to the firm size-wage relations, at least for the formal sector. Job characteristics did not explain major variation in firm-size wage relationships. Thus, apart from human capital characteristics, most theories cannot explain the wage premium received by large firms. The results further indicate that capital intensity and firm productivity are important in shaping the firm size wage premium, although they did not alter the size effect much

Revision of consumer price index basket in Zimbabwe

The Zimbabwe Statistical Agency (ZIMSTAT) introduced a revised Consumer Price Index (CPI) basket, effective January 2013. Periodic revisions of the expenditure weights are necessary so that the CPI reflects price changes of current spending patterns. The latest 2012 revision of CPI basket shows an increase in weight of basic items such as food and non-alcoholic beverages, education, housing, water, electricity, gas and other fuels, health, clothing and footwear divisions of the CPI. The depressed disposable incomes have led to consumers reverting to the ‘basic’ basket. Communication division, however, increased in weight, owing to the impact of technology on the consumers. As the Consumer Price Index is used for many purposes, and affects various policies, it is important to maintain the public credibility on inflation statistics through improving its timeliness, relevance and accuracy. In this regard, the CPI basket should be frequently updated. Thus, the relatively long time of about 11 years taken before revising the CPI basket in Zimbabwe in the face of clear changing expenditures, is not welcome and may have contributed to a larger extent to criticisms about the credibility of inflation figures in the country

A Comparative Study of the Effect of MgO and CaCO3 as Support Materials in the Synthesis of Carbon Nanotubes with Fe/Co as Catalyst

A comparative study of the effect of magnesium oxide and calcium carbonate as support material in the synthesis of carbon nanotubes using the catalyst Fe/Co is presented. The synthesized carbon nanotubes were characterized with Raman spectroscopy, scanning electron spectroscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction spectroscopy (XRD), and energy dispersive spectroscopy (EDS). The morphology of the carbon nanotubes synthesized with magnesium oxide as support material gives rise to carbon nanotubes with consistent and well-defined structure unlike that synthesized with calcium carbonate. The ID/IG ratio of synthesized carbon nanotubes (CNTs) was 0.8544 for magnesium oxide supported compared to 0.8501 for calcium carbonate supported carbon nanotube

Adsorption behaviors of crystal violet from aqueous solution using Anatolian black pine (Pinus nigra Arnold.): kinetic and equilibrium studies

In this study, Anatolian black pine (ABP, Pinus nigra Arnold.) was evaluated as biosorbent for removal of crystal violet (CV) from aqueous solution. The influence of operational parameters including solution pH, initial CV concentration, biosorbent dosage, contact time, and temperature were studied in batch systems. The adsorption data followed well Langmuir isotherm with a maximum biosorption capacity of 12.36 mg/g. The equilibrium data were better fitted with pseudo-second-order kinetic model (R2 ˃ 0.99). Moreover, the thermodynamic parameters indicated that the CV biosorption was feasible, spontaneous, and endothermic process. This study showed that ABP (Pinus nigra Arnold.) can be used to remove CV from aqueous solutions. © 2019, © 2019 Taylor & Francis Group, LLC