Volume 29, No. 1 (2023)

SYNTHESIS AND CHARACTERIZATION BY INFRARED AND MOSSBAUER SPECTROSCOPIES OF SOME NEW SnR2 (R = Me, Ph, Bu) RESIDUE CONTAINING ARBOXYALKYLPHOSPHONATE ADDUCTS AND DERIVATIVES

MOUHAMADOU SEMBENE BOYE(1,2*), MOUHAMADOU BIRAME DIOP(2), MODOU SARR(2), AMINATA DIASSE-SARR(2), LIBASSE DIOP(2), ALAIN WATTIAUX3

Four new carboxyalkylphosphonate SnR2 residue (R = Me, Ph, Bu) containing adducts and derivatives i.e. {(Cy2NH2)3(O2CCH2PO3)(SnBu2Cl2)} (1), {[(SnMe2Cl)(O2CCH2PO3H2)]4[Cy2NH2Cl]} (2), {(Me4N)(SnPh2Cl)[O2C(CH2)2 PO3H](SnPh2)[O2C(CH2)2PO3H]} (3) and {(Cy2NH2)2(O2CCH2PO3H)(SnPh2Cl2)2} (4), have been synthesized from one-pot reactions carried out in solution. All compounds have been investigated by spectral techniques (infrared and Mossbauer). The spectral studies have evidenced presence of several characteristic bands, especially υ (C=O), υ (OH), υ (CO2–), υ (PO32–) vibrations coming from carboxyalkylphosphonate ions, with wide absorption due to the NH2 groups coming from the dicyclohexylammonium counter ion (for 1, 2 and 4) and the intense doublet which show the presence of phenyl groups (for 3 and 4). In the solid state, the proposed structures are discrete or of infinite chain however hydrogen bonding patterns may occur. Event in this investigation is the presence, for compound 3, of two types of arrangement at Sn centers viz. an octahedron and a trigonal bipyramidal whose presence are ascertained by the Mossbauer parameters. The neutral or acidic carboxyalkylphosphonate ions exhibit a diversity of coordination behavior towards the Sn atoms: monochelating (carboxylate and phosphonate O-donor), monochelating through the carboxylate and unidentate coordinating O-donor through the phosphonic acid or acidic phosphonate, bichelating with chelations from carboxylate and acidic phosphonate, and unidentate from both the carboxylate and phosphonic acid.

THE IMPACT OF DIGITAL EDUCATION TOWARDS A SUSTAINABLE DIGITAL CONSUMER IN THE ERA OF CIRCULAR ECONOMY

SONIA BUDZ(1), IOANA BUCUR-TEODORESCU (1*), BOGDAN CRISTIAN ONETE (2)

A more sustainable economy and society presume more sustainable behavior in terms of consumption. A change in this behavior could be brought by a change in demand. In other words, a change in the demand could be facilitated by one’s financial and digital education. The circular economy implies the reuse and recycling of products and materials over and over again; thus, the life cycle of products and materials is extended. Engaging in recycling should have future benefits. Recycling behavior and sustainability are interrelated, the recycling process is viewed as a key issue in sustainability and prevails as pro-environmental consumer behavior. It is already known that significant changes in individual behavior are essential for society to move toward sustainability. This paper aims to explore from a quantitative perspective if digital education has an impact on consumer behavior in terms of sustainability in the era of the circular economy. This research is useful for all providers, consumers, and stakeholders involved in different businesses

VARIANTS FOR EVALUATING THE RIGIDITY OF FLAT RING FLANGES

RADU I. IATAN (1), GHEORGHITA TOMESCU (1), MELANIA CORLECIUC (MITUCA) (2), GEORGETA ROMAN (URSE) (*1) , NICOLETA SPOREA (1), IULIANA- MARLENA PRODEA (1), IOLANDA CONSTANTA PANAIT (1)

This paper describes an analytical way of comparative evaluation of the stiffnesses developed in assemblies with flat ring flanges, of optional type, welded to the cylindrical body of a pressure vessel. Based on the theory of the compatibility of deformations (radial displacements and rotations), the mathematical expressions necessary for the evaluation of the unitary radial bending moments and the unitary shearing forces of connection are established. With their help, the values of the rotation angles of the rings can be calculated and compared with the admissible ones. The present analysis considers the quantitative effect of the deformed gasket and the stiffness of the curved/bent screws on the tightness of the system. The methodology is flexible by introducing some selection factors, so that the mentioned influences can be easily separated and compared

ENERGY PRODUCTION OF A HYBRID SOLAR ELECTRIC VEHICLE CHARGING SYSTEM

RÓBERT ISTÓK(*)

As a consequence of increasing electric vehicle number, the number of electric vehicle chargers are increasing too. The main advantage of electric vehicle is the zero CO2 emission. One of the biggest advantage of solar electric vehicle charger built at Óbuda University is that offer the possibility to charge the electric vehicle with energy which are coming from a solar system. The system contains a solar part, an energy storage part and the electric vehicle charger part. The internet connection of the system gives the possibility to have real time information about the system. Continuous monitoring of the system, assure an overview on source and on amount of energy consumption

RESERVE ESTIMATION FOR AN AQUIFER-SUPPORTED RESERVOIR USING MATERIAL BALANCE

WILFRED CHINEDU OKOLOGUME (*1), GEORGE GEORGE EKEH PROMISE1

This study uses a straight-line material balance method to estimate the reserves of an undersaturated reservoir supported by an aquifer. Some computer algorithms to implement Van-Everdingen and Hurst models (VEHM) to calculate cumulative water influx were envisaged through the study's developed tool "QUANTIFY". The tool was then tested using published data. The Original Oil in Place (OOIP) for the given data was estimated to be 312.32 MMSTB with an R2 value of 0.99483. Subsequently, a comparative analysis was performed on the results obtained from MBAL and QUANTIFY, using Dake's result as a base/correct case. It was estimated that OOIP for QUANTIFY had a 0.1% error rate, while MBAL, a commercial software used to verify the result, had a 1.2% error rate. Invariably, the percentage errors were lower for the QUANTIFY software than for MBAL. The 3D plot of the reservoir energy drive from the "QUANTIFY" software, which was used to visualize the reservoir energy qualitatively, shows that the reservoir was mostly driven by water influx and fluid expansion. This study has demonstrated that "Water Influx" parameters can be computed appropriately without the use of charts or tables. The study has strengthened the validity of the Van Everdingen and Hurst aquifer model for reserve estimation for an aquifer-supported reservoir.

IMPACT OF DIESEL FUEL GENERATORS ON SOIL HEAVY METALS

SEUN OYELAMI(1*) , OYETUNJI BABATUNDE OKEDERE(2), KEHINDE ADENIKE OYEWOLE(2), KAZEEM OLAWALE RABIU(2), OGUNTOLA JELIL ALAMU(1), MUTIU DUNMOYE SULAIMON(1), SAHEED OLUSANJO LAWAL(1)

Heavy metals are ubiquitous and are released into the atmosphere/ environment by a variety of natural processes, but their quantities have been greatly augmented by anthropogenic activities. This study investigated the concentration of heavy metals Iron (Fe), Arsenic (As), Cadmium (Cd), Chromium (Cr), Zinc (Zn), Manganese (Mn) and Lead (Pb) in the soil around the power plant obtained at the old power plant, new power plant and a far-away point from the plants which served as the control. In each location, two samples were obtained top layer and bottom layer of soil. Standard laboratory methods were employed for all the analyses. High concentration was obtained for the selected heavy metals in the soil at both the old and the new power plants with Arsenic having an average of 0.67 mg/kg and 0.40 mg/kg, Lead having an average of 2.63 mg/kg and 1.67 mg/kg, Iron having 1.25 mg/kg and 0.95 mg/kg, Chromium having 1.08 mg/kg and 0.67 mg/kg, Cadmium having 1.46 mg/kg and 0.54 mg/kg, Manganese having 1.97 mg/kg and 1.86 mg/kg and Zinc having 2.43 mg/kg and 0.86 mg/kg at the old and new site respectively. All the obtained concentration levels are above the permissible limit of the United States, United Kingdom, Europe and WHO. It is expedient that necessary measures be put in place to control the emissions from the plants to reduce the contaminating impact of the soil around the power plant as well as moving some human intakes far from the locations

SUPPORT VECTOR MACHINE FOR HUMAN IDENTIFICATION BASED ON NON-FIDUCIAL FEATURES OF THE ECG

HATEM ZEHIR(1*) , TOUFIK HAFS(1), SARA DAAS(1), AMINE NAIT-ALI(2)

The demand for reliable identification systems has grown recently. Using the mean frequency, median frequency, band power, and Welch power spectral density (PSD) of ECG data, we proposed a novel biometric approach in this study. ECG signals are more secure than other traditional biometric modalities because they are impossible to forge and duplicate. Three different support vector machine classifiers—linear SVM, quadratic SVM, and cubic SVM—are employed for the classification. The MIT-BIH arrhythmia database is used to evaluate the suggested method's precision. For the linear SVM, quadratic SVM, and cubic SVM, respectively, test accuracy of 93.6%, 96.4%, and 97.0% was obtained.