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Sustaining a Healthy Environment whilst Utilizing Wastes as Energy Sources: Physicochemical Analysis of Solid Wastes in Awka, Nigeria

100%

Ayadinuno E. O. , Njoku U. B. , Akakuru O. U.

World News of Natural Sciences

2021

tom 36

75-87

The physicochemical properties of solid wastes were determined to unravel the individual components of solid wastes such as density, moisture content, and percentage mass. The chemical composition of each waste component was also determined. Methods adopted in the determination included the load count and mass volume methods, the proximate and ultimate analysis method. Collectively, the percentage chemical constituents were obtained from the different solid waste samples analyzed. Energy values obtained from the constituents are 47.6 and 47.10 kJ/kg when Dulong’s and Davies’ formula were applied, respectively. The results revealed that paper and cardboard, metals, plastics, and wood make up the highest composition in the five major waste dumpsites studied in Awka, Nigeria. It also showed that carbon and oxygen contents are high in most of the solid waste components when compared to other chemical constituents and that these wastes can be converted to useful energy in furtherance of sustainable development.

Active moss biomonitoring of trace elements air pollution in Chisinau, Republic of Moldova

75%

Zinicovscaia I. , Urošević M. A. , Vergel K. , Vieru E. , Frontasyeva M. V. , Povar I. , Duca G.

Ecological Chemistry and Engineering. S

2018

tom Vol. 25, nr 3

361--372

For the first time active moss biomonitoring was used to assess trace element deposition in the capital of the Republic of Moldova, Chisinau. Moss Sphagnum girgensohnii samples were exposed in bags at three sites of Chisinau from October, 2016 to March, 2017. The content of 30 elements: Na, Mg, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Br, Rb, Mo, Sr, Sb, Ba, La, Ce, Cs, Hf, Th, Cu, Cd, Pb, and U in the exposed and unexposed mosses was determined by neutron activation analysis and atomic absorption spectrometry. According to the relative accumulation factor, the most abundant elements in the samples were V, Cr, Fe, Ba, La, As, Sb, U, and Pb. Such elements as Cl, K, and Rb were depleted from the moss tissue during the time of exposure. Principal component analysis was used to identify and characterize different pollution sources. The obtained results indicate that the use of S. girgensohnii moss bags is a simple and inexpensive technique to monitor major and trace element content in the air of urban area.