Volume 24, No. 1 (2018)

MAPPING OF SALTWATER INTRUSION AT IGBOKODA, SOUTHWESTERN, NIGERIA USING COMBINED GEOPHYSICAL AND CHEMICAL TECHNIQUES

JAMES ADEGOKE(1), WILFRED IGBOAMA(*2), EMMANUEL ADETUWO(1)

This research work was set out to map saltwater intrusion in Igbokoda area of Ilaje, Ondo State, Southwestern, Nigeria using combined geophysical and chemical techniques. Eight (8) Vertical Electrical sounding were carried out using the Schlumberger Electrode array system with maximum spread of (AB/2) 133 m and water samples were acquired and analysed using atomic absorption spectrometer. The VES data was interpreted by the method of partial curve matching and computer iteration technique using Winresist software. The result obtained revealed four geoelectric layers. The saltwater intrusion originated from movement of seawater into the freshwater aquifer coupled with human activities.

EMISSIONS MONITORING OF HEAVY METALS AND THEIR COMPOUNDS RESULTED FROM COMBUSTION PROCESSES IN CLINKER KILNS IN ROMANIA

CRISTIAN CIOBANU(1), GHEORGHE VOICU(2*), MAGDALENA – LAURA TOMA(2), PAULA TUDOR(2)

With the dust arising from the clinker kilns and grill coolers (the major pollution sources in a cement plant), also heavy metals and their compounds (in the form of powders and vaporous), originating from fuels and raw materials, are pumped into the air. The paper presents some aspects regarding the monitoring of heavy metals contained in the combustion gases from a Romanian cement factory. The fuels used in the incinerator varied from coal/petroleum coke, refuse oils (from waste oils and their emulsions, up to sludge, paraffin, tars, contaminated soil), rubber (including whole used tires), plastic, paper, leather, textiles, wood (including sawdust), as such or impregnated/contaminated with various substances from industrial sources or sorted household wastes, sludge (previously dried) from wastewater treatment plants. In addition, the list of over 100 types of waste that can be co-processed can be found in integrated authorizations of cement plants. However, the level of heavy metals in the combustion gases was in allowed limits.

ANALYSIS OF USING DIGITAL LEARNING MATERIALS IN ENGINEERING LABORATORY COURSES

TSVETELINA GEORGIEVA(1*), TZVETELIN GUEORGUIEV(1), SEHER KADIROVA(1), BORIS EVSTATIEV(1), NIKOLAY MIHAILOV(1)

The paper presents an analysis of the use of digital learning materials in engineering laboratory courses. Interviews have been conducted with lecturers from several engineering faculties of the University of Ruse ‘Angel Kanchev’, such as: the Faculty of Electrical Engineering, Electronics and Automation, the Faculty of Transport, and the Faculty of Mechanical and Manufacturing Engineering. The aim of the interviews is to investigate the capacity and understanding of the lecturers in respect to using digital learning materials in laboratory courses. The obtained results demonstrate that digital learning materials are perceived as a useful tool to achieve better engagement of students in the educational processes. This would require continuous additional efforts by the teaching staff and permanent updating of their specific and digital competences.

DENSE GLASS FOAM PRODUCED IN MICROWAVE FIELD

LUCIAN PAUNESCU(1*), MARIUS FLORIN DRAGOESCU(1), SORIN MIRCEA AXINTE(2), BOGDAN VALENTIN PAUNESCU(3)

Experimental results obtained in the process of manufacturing dense glass foam using the microwave energy are presented in the work. The glass foam is produced from bottle glass waste, calcium carbonate as foaming agent and borax as fluxing agent. The high compressive strength (2.5 - 6.2 MPa) is the main mechanical feature of this product, which together with other physical and morphological features (apparent density 0.60 – 0.90 g/cm3, porosity 59.1 – 72.7%, thermal conductivity 0.081 – 0.105 W m K, water absorption 0.5 – 1.0%, pore size 0.5 – 3 mm), are appropriate for using as a substitute for similar building materials existing on the market.

NEW MX2 AND M’Cl3 (M = Cu, Zn; M’= Y, Dy, Pr; X = Cl, Br) MALEATO COMPLEXES AND TETRAPHENYLANTIMONY FORMIATE ADDUCT: SYNTHESIS AND INFRARED STUDY

DAME SEYE(*1), CHEIKH ABDOUL KHADIR DIOP(1), ASSANE TOURE(1), LIBASSE DIOP(1)

Eleven complexes and adduct have been synthesized and studied by infrared. The suggested structures are discrete with tetrahedral, trigonal bipyramidal, square planar or octahedral environments around Zn, Ni, Hg and Cu centres – the coordination number is eight in the yttrium compound and ten in the dysprosium one-. The maleate anion behaves as a bidentate, a monochelating, a bichelating or a tetradentate ligand while the formiate anion behaves as a monodentate ligand. For compounds containing a protonated amine or a methanol molecule, when hydrogen bonds are considered a supramolecular architecture may be obtained.

SOLVING TECHNICAL PROBLEMS THROUGH EQUATIONS

DANILA VIERU(1), GHEORGHE VOICU(1*), LAURA TOMA(1), PAULA TUDOR(1)

The need for solid household waste (MSW) generated by economic and domestic activities is continuous and should be imposed to protect the health of the population and environmental factors. After sorting the generated waste, „the remaining residue” favours the occurrence of some pollutants, among which we mention suspended particulates, disagreeable odours, greenhouse gases, etc. This waste has to be managed in safe health and environment, no matter where it was generated. Managing them means either storing in statutory environmental protection facilities or incinerating in authorized installations with integrated environmental permitting. Waste storage may be subject to a mathematical equation called the time equation of a landfill. On the basis of such equation, it will be possible to calculate annually the amount of degraded waste gas generating gas (LFG) containing CH4 and CO2. The amount of degraded waste means waste with high dissolved organic carbon (DOC).