Bulgarian Journal of Science Education in 2018
B. V. Toshev
Education: Theory & Practice
The Successful Teacher Through the Perspective of Constructivist Ideas [In Bulgarian]
Резюме. Modern education is characterised by student-centered classroom, focus on real-life preparation and lifelong learning, modern and challenging learning environment. In these dynamic and ongoing changes in education, a center role plays the teachers. They need to have the necessary attitudes to face all challenges and develop themselves, and also a set of skills that differ from those of the teachers of decades ago. The aim of this article is to trace historically the concepts of teachersâ€™ professional profile around the World and in Bulgaria, and on this basis to bring out the skills necessary for modern science teachers. Attention is drawn to the change in the role of the teacher, the learning environment, technological progress, family values. The focus of the study is on the views of the founders of constructivism â€“ John Dewey, Lev Vygotsky, Jerome Bruner and others â€“ for the professional and personal qualities of the teacher.
Keywords: Ñhemistry education, constructivism, science teachers, teaching skills
V. Tsvetkov, E. Boiadjieva
Education: Theory & Practice
Bulgarian High-School Students’ Views on the Nature of Science and Scientific Inquiry [In Bulgarian]
Резюме. This article presents the results of a diagnostic survey conducted in the academic school year 2016/2017, involving 937 students from non-specialized schools (secondary schools, language and maths high schools, vocational high schools) in 7 districts in Bulgaria. The survey was aimed at providing an overall picture of important aspects of scientific literacy as seen by Bulgarian high-school students. The survey tool was a modified version (Clough et al., 2010; Moss, 2012) of the SUSSI questionnaire â€“ Student Understanding of Science and Scientific Inquiry (Liang et al., 2006), translated into Bulgarian. The quantitative analysis of the data gathered through multiple choice questions shows that 59% of the students involved in the survey had an undefined view, 37% â€“ a forming view to an informed view, 3% â€“ an informed view, and only 1% â€“ a forming view to a naÃ¯ve view. Studentsâ€™ views dependencies on their cognitive outcomes, gender and the type of school they attend are highlighted through a correspondence analysis.
Keywords: nature of science, scientific inquiry, correspondence analysis
Z. Garova, V. Noncheva, Y. Dimova
Integration of Science, Technology, Engineering and Mathematics: The Multidisciplinary Approach to Enhance the Environmental Literacy of Prospective Chemistry Teachers
Резюме. This research investigates the impacts of the implementation of Science, Technology, Engineering, and Mathematics (STEM) education in Environmental Chemistry course to enhance environmental literacy of prospective chemistry teacher. The research method used was quasi-experiment. Problem based learning (PBL) approach was implemented at the control group, while PBL-STEM was implemented at the experimental group. The dimensions of Environmental literacy to be concerned were environmental competence, environmental knowledge, and attitudes towards environment. The results of research reveal that PBL-STEM education can be used as an effective approach to improve the environmental literacy of prospective chemistry teachers. The average improvement of environmental literacy and its dimensions in the experimental group was significantly higher than the control group.
Keywords: environmental literacy, PBL, prospective chemistry teachers, STEM education
R. Farwati, T. Suhery, A. Permanasary, H. Firman
Results of the Education of Prospective Biology Teachers’ Students for Formation of Methodological Skills for Work with Interactive Methods [In Bulgarian]
Резюме. The study is devoted to the problem of organization and realization of professional education of students â€“ future biology teachers, for formation their methodological skills for work with interactive methods of education with the school pupils. There has been presented fragments of the methodological structure of the lessons to the students. The analysis of the results of the study enables us to draw the conclusion that the presented lessons seem to be successful.
Keywords: prospective biology teachers, observation in biology, interactive methods, methodological skills
M. Boycheva, R. Davidova, A. Petrova
Experimental and Computational Study of Co(II), Ni(II) and Zn(II) Complexes with the Azo Dye Derived from 2-Amino-4-Methyl Pyridine and Î²-Naphtol
Резюме. A series of metal complexes of Co(II), Ni(II), Cu(II) and Zn(II) complexes with the azodye ligand derived from the 4-methyl-2-aminopyridine and Î²-napthol have been synthesised. These complexes and the ligand have been characterised by analytical and spectral techniques such as IR, NMR, electronic and magnetic measurement. The structural compositions of the ligand and complexes have been determined by FAB-MS structural studies. The computational study of studied compounds has been made to determine geometrical parameters and electronic parameters. The experimental data of the compounds are compared with the computationally generated data. The structural activity relationships of all the compounds have been computed to explain their biological properties.
Keywords: metallochromic reagents, computational study, correlation coefficient, MEP study
S. N. Chaulia
Zagreb Connection Indices of TiO2 Nanotubes
Резюме. The Zagreb connection indices are molecular descriptors (topological indices) which have recently been introduced by Ali & TrinajstiÄ‡ (2018). A novel/old modification of the first Zagreb index, Mol. Inform., to appear]. This paper is devoted to establishing general expressions for calculating the Zagreb connection indices of a well-known nanostructure, namely the Titania nanotube.
Keywords: molecular structure descriptor, Zagreb connection indices, titania nanotube
S. Khalid, J. Kok, A. Ali, M. Bashir
From the Research Laboratories
Effect of Untreated Olive Mill Wastewater of Seed Germination, Seedling Growth and Biochemical of Maize (Zea mays L.)
Резюме. Olive mill wastewater (OMW) is considered as phytotoxic and thus an environmentally hazardous material, it is one of the most severe environmental factors that reduces and limits growth and development of plants. This study was conducted under laboratory conditions in order to evaluate the effect of OMW at three concentrations on seeds germination and seedling growth of maize (Zea mays L.). Seeds were soaked then placed in petri-dishes and irrigated with 1, 5 and 10% v/v concentrations of OMW. A control was moistened with distilled water. The germination percentage, root and shoot length, phytotoxicity percentage of root and shoot, and contents biochemical like total proteins, oil, total soluble sugars and starch for both the endosperm and the embryo of maize were observed. The results obtained showed beneficial effects using low concentrations of OMW whereas the treated plants with 1% of OMW showed a slight improvement in all the above growth parameters and contents biochemical, but the highest levels 5 and 10% of OMW had a negative effect compared with control.
Keywords: Zea mays L., olive mill wastewater, germination, seedling growth, morphology parameter, biochemical contents endosperm, embryo
M. Abu-Hassan, A. Malo, N. Al-Muhanna
From the Research Laboratories
Synthesis of New 3-[(Chromen-3-yl)-Ethylideneamino]-Phenyl]-Thiazolidin-4-ones and Their Antibacterial Activity
Резюме. A series of novel substituted thiazolidyn-4-ones were synthesized by cyclization of various Schiff bases of chromen-3-one with thioacetic acid. 3-(1-4-Amino-phenylamino)-ethyl-4-hydroxybenzopyran-2-one 3 is synthesized in high yield by condensation reaction of 4-hydroxy-3-acetylcoumarin 2 and 1,4-benzenediamine. The catalytic condensation of product 3 with benzaldehyde and their analogues (salicylaldehyde and 3-nitrobenzaldehyde) yielded corresponding 3-[1-(4-benzylidene-amino)-phenylamino]-ethyl-4-hydroxybenzopyran-2-ones 4(a-c). The cyclization reaction of compounds 4(a-c) with thioacetic acid yielded corresponding substituted thiazolidin-4-ones 5(a-c). The structures of the synthesised compounds were established by FT-IR and NMR spectrometric data and their elemental analysis. Compounds of series 4(a-c) and 5(a-c) were screened for their antibacterial activity against S. aureus, E. coli and Klebsiella by Diffusion Disc Method. Antibacterial activity of the compounds 4(a-c) and 5(a-c) against S. aureus, E. coli and Klebsiella was examined by measuring the zones of inhibition around the disks impregnated with the corresponding solutions in N,N-DMF concentration 2 mg/mL , 4 mg/mL and 6 mg/mL. Compounds of series 4 exhibited significant antibacterial activity, whereas compounds of series 5 displayed moderate activity against these microorganisms. The impact of substitutions in antimicrobial activity was also explored.
Keywords:t hiazolidin-4-one, benzopyran-2-on, condensiation, cyclization, zones of inhibition
R. Hoti, N. Troni, H. Ismaili, M. Pllana, M. Pacarizi, V. Thaci, G. Mulliqi-Osmani
Science and Society
The Influence of Changes in the Hydrological Regime of the Ural River in the West Kazakhstan Region on Fish Resources
Резюме. The Ural River is one of the main fisheries reservoirs of Kazakhstan. Its hydrological regime has been unstable over the past 10 years, which has affected the formation of fish resources. The present study has shown that commercial fish populations decrease from year to year due to the deterioration of spawning conditions in low-water years, when spawning grounds are not fully watered. In these years, the spawning efficiency decreased from 11% to 70%.
Keywords: hydrological regime, Ural River, fish resources, spawning conditions
A. Kim, T. Murzashev, D. Tagayev, Z. Karagoishin
Science and Society
An Experiment with a Mobile Station and Dispersion Modeling in Search of an Answer to the Question Whether Traffic Is the Source of Peak Gassing with Nitrogen Oxides Over Stara Zagora, Bulgaria [In Bu
Резюме. Between 2006 and 2012, the stationary automatic air quality monitoring station in Stara Zagora, Bulgaria repeatedly registered peaks of the nitrogen dioxide concentration over-treshold levels (the highest so far in Bulgaria), with unknown origin. The main suspect was traffic Ð¾n the street near the measuring station. The behavior and intensity of air pollution with nitrogen oxides emitted by the motor vehicles crossing a city junction, with three times more intense traffic than that near the stationary station, was investigated. The study included vehicle counting and subsequent dispersion modeling. At the time of counting, total urban nitrogen pollution in the junction area was measured by a mobile station. Within seven years – 2010, 2011 and 2017 were conducted three studies of the junction. It was found that for 7 years in the city’s car fleet only the number of small passenger cars is decreased (49 times). The maximum concentrations of nitrogen oxides, both measured and calculated, are close in magnitude and are several times smaller than the peak values measured by the stationary station. That is, the analysis of the experiment data showed that the traffic is not the source of the peak pollution with nitrogen dioxide over Stara Zagora. Nitrogen oxides pollution often concentrates around the southwestern corner of city junctions due to the prevailing wind direction from the north-northeast.
Keywords: urban air pollution, nitrogen oxides, nitrogen dioxide, mobile station, dispersion modeling
N. Takuchev, Y. Stoyanova