|Education: Theory & Practice:|
|D. Dimitrova-Radojchikj, N. Chichevska-Jovanova|
Teacher's Acceptance of Students with Disability
Full text: PDF (348 K)
'Scientific Disciplines' Awareness Questionnaire
Full text: PDF (814 K)
|G. Kumar, A. Munyaneza, G. Ditsie|
Spectral, Magnetochemical and Thermogravimetric Analysis (TGA) of Transition Metal Complexes with N^O Types Ligands
Full text: PDF (671 K)
Multimedia Tests in Geography [In Bulgarian]
Full text: PDF (357 K)
|V. Radeva, D. Kyurkchieva, D. Dimitrov, G. Borisov|
Remote Astronomical Observations - Innovation in Astronomy Education [In Bulgarian]
Full text: PDF (4013 K)
|2011 - International Year of Chemistry:|
|Z. Eskandari, Nabi.A Ebrahimi|
Iranian University Students' Perception of Chemistry Laboratory Environment
Full text: PDF (566 K)
|From the Research Laboratories:|
|A.H. Farhadian, M.K. Tehrani, M.H. Keshavarz, S.M.R. Darbany, M. Karimi, A.H. Rezayi|
Application of Laser Induced Breakdown Spectroscopy as Nondestructive and Safe Analysis Method for Composite Solid Propellants
Full text: PDF (1257 K)
|A. Ghasemizadeh, A. Semnani, H.S. Langeroodi, A.N. Ejhieh|
The Effect of Dioctylphtalate on Initial Properties and Field Performance of Some Semisynthetic Engine Oils
Full text: PDF (404 K)
|Science and Society:|
|F. Faiku, A. Haziri, F. Gashi, N. Troni|
Quality Assurance of River's Water of Lumbardhi Peja (Kosovo)
Full text: PDF (2481 K)
|New Information Media:|
|M. Kirova, N. Kostova, M. Trendafilova|
Application of Informational and Communicational Technologies in Chemistry Education: Opinions of Teachers in Chemistry from One Region of Bulgaria [In Bulgarian]
Full text: PDF (944 K)
Khimiya, Volume 24, Issue 5(2015)
Khimiya. 24, 647-656 (2015) Author(s): D. Dimitrova-Radojchikj, N. Chichevska-Jovanova:
Abstract.The success of inclusive education depends on the acceptance and the ability of teachers to facilitate a good learning environment for all students. The purpose of this study was to investigate teachers’ acceptance of students with disability in their classroom, and the factors that influenced such acceptances. Quantitative research was used to gather information from general education teachers. The sample consisted of 122 teachers at 6 schools. The study found that the school teachers irrespective of their age and experiences have similar scores on Diversity Acceptance Checklist (DAC) of students with disabilities.
Keywords: acceptance, teachers, students with disability, inclusive education
Khimiya. 24, 657-677 (2015) Author(s): B.H.S. Thimmappa:
Abstract.Interesting direct questions related to common science branches with a specialized knowledge is presented as an additional learning material for the benefit of young minds with a spirit of inquiry. This questionnaire is a mix of the right technical words used to describe scientific fields and some specific logical analysis, designed to develop basic awareness, enrich scientific thinking process and enhance understanding of the true meaning of the terms used. The answers to this practice quiz of 162 diverse questions on scientific disciplines are listed at the end of the text. This is an attempt to awaken the natural curiosity of young minds and help in engraving the keywords used in describing the branches of science.
Keywords: interdisciplinary education, science branches, self-directed learning, supplementary material, active learning
Khimiya. 24, 678-690 (2015) Author(s): G. Kumar, A. Munyaneza, G. Ditsie:
Abstract.Transition metal complexes, Na2[M(L1L2)].H2O, where M = Cu(II), Co(II) and Ni(II) ions ; L1 and L2 are the anions of phenylalanine (Phe-) and nitrilotriacetic acid (NTA3-)respectively have been synthesized and characterized by elemental analysis, spectral (IR,UV in solid state), magnetic susceptibility and thermogravimetric analysis (TGA). All the complexes have been suggested to show six fold octahedral geometry around the metal ion. Phenylalanine and nitrilotriacetic acid demonstrate bidentate and tetradentate behavior respectively, coordinating through their respective nitrogen atom and the oxygen atom (s) of the carboxylate group. Thermal behavior of Ni(II) complex is quite different from those of Cu(II) and Co(II) complexes which show similar type of thermal behavior. Based on their decomposition temperature, the thermal stability of the three complexes can be rated as Cu > Ni > Co.
Keywords:transition metal complexes, octahedral, phenylalanine, nitrilotriacetic acid, thermal analysis
Khimiya. 24, 691-700 (2015) Author(s): I. Drenovski:
Abstract.In recent years the practice of national competitions, festivals and Geography Olympiads has included multimedia tests. Both structuring of these tests and their use for an objective assessment of knowledge and skills of students still remain methodical "terra incognita." Definition of those tests is given and the way of their design and implementation in practice are clarified in the present paper.
Keywords: geography education, multimedia tests, geography olympiads and competitions, matriculation exams
Khimiya. 24, 701-714 (2015) Author(s): V. Radeva, D. Kyurkchieva, D. Dimitrov, G. Borisov:
Abstract.The article shows the advantages of the remote astronomical observations as a new approach for astronomical education. We present the results of our remote astronomical observations with the Faulkes telescopes in the real educational process. This research-based method provoked the interest of the students and created motivation for future realization in the field of natural science.
Keywords: interactive educational methods, telescopes, astronomical observations
Khimiya. 24, 715-733 (2015) Author(s): Z. Eskandari, Nabi.A Ebrahimi:
Abstract.This article reports the development, validation and application of a Persian version of the Science Laboratory Environment Inventory (SLEI). The SLEI was carefully translated into Persian and field tested with a sample of 311 Iranian university students in 21chemistry laboratory classes. Confirmatory factor analysis proved that the Persian version of SLEI is a valid instrument. Further exploration showed that the instrument exhibited internal consistency reliability for both its actual and preferred forms. Comparison of Iranian university students’ scores on actual and preferred forms of the questionnaire revealed that students were not satisfied and preferred a more positive chemistry laboratory environment on all scales. The results will be of significance for chemistry educators to create more efficient, constructive, creative, critical and democratic chemistry laboratory environments. The work is distinctive since it is the first learning environment study delving through chemistry laboratory classrooms in Iran.
Keywords: chemistry laboratory environment, SLEI, learning environments research, satisfaction
Khimiya. 24, 734-744 (2015) Author(s): A.H. Farhadian, M.K. Tehrani, M.H. Keshavarz, S.M.R. Darbany, M. Karimi, A.H. Rezayi:
Abstract.Nowadays many methods have been proposed for the analysis and evaluation of the energetic materials and their properties. In this work, laser induced breakdown spectroscopy (LIBS) as a new method was introduced as a safe and nondestructive analysis method to study chemical structure of composite solid propellants. Spectral peaks of the carbon, hydrogen, nitrogen, oxygen and aluminum atoms, which belong to the binder polymer structure and metallic fuel, were observed. The presence of emission lines relevant to the chlorine atoms can be used to represent using ammonium perchlorate as oxidizer. Moreover, emission lines relevant to the elements such as calcium, potassium, sodium and iron were confirmed to show the use of suitable additives for increasing performance and processing. In addition, C2 swan bands and CN violet radiation were observed that are due to reaction of carbon atoms of propellant and nitrogen atoms of air.
Keywords: Laser Induced Breakdown Spectroscopy (LIBS), solid composite propellant, HTPB, safety
Khimiya. 24, 745-758 (2015) Author(s): A. Ghasemizadeh, A. Semnani, H.S. Langeroodi, A.N. Ejhieh:
Abstract.Several semisynthetic engine oils containing solvent neutral-150 (SN-150) and solvent neutral-500 (SN-500) as mineral constituent and di-2-ethyl-hexylphthalate (DOP) as synthetic constituent has been formulated. Physical properties of the prepared oils have been measured by standard methods. The concentration of twenty three elements in the oils has also been determined by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). The physical measurements and chemical analysis were repeated after 5000 kilometer of running. By comparison of the obtained data, the influence of ester on initial properties of fresh formulated oils, as well as its impact on the field performance of used ones have been investigated. The result indicate that upon ester introduction properties such as biodegradability, coefficient of friction, wear, suppression of additive depletion, CCS, color, and pour point will be modified. However, specifications such as oxidation stability and hydrolytic stabilities will be downgraded. The overall obtained data indicate that, upon 20% increase of DOP content most of the useful properties of ester will be gained.
Keywords: lubricants, SN-150, SN-500, ester, DOP, engine oils, ICP-OES, engine oil, biodegradability, wear
Khimiya. 24, 759-775 (2015) Author(s): F. Faiku, A. Haziri, F. Gashi, N. Troni:
Abstract.The surface waters in Kosovo are predominately polluted, and it is evidential that domestic and industrial wastewaters treatment plants still don’t exist in any of the cities in Kosovo. In this research work we have analyzed 67 elements in the water of Lumbardhi Peja. Results of some toxic elements are as: Cu (4.0 - 13.5 μg dm-3), Zn (7.1 - 34.1 μg dm-3), Pb (0.8 - 4.32 μg dm-3), Cd (0.15 - 0.07 μg dm-3), Mn (2.7 - 120 μg dm-3), As (0.18 - 0.71 μg dm-3), Cr (0.5 - 1.5 μg dm-3), Fe (30 - 760 μg dm-3), Ni (1.3 – 19.5 μg dm-3), Sb (0.05 - 0.1 μg dm-3), Al (79 - 418 μg dm-3). Also some physico-chemical parameters are determined: air temperature, water temperature, pH, electrical conductivity (EC), total hardness, Cl-, SO42-, NO3- and NO2- . Results of some parameters and ecotoxic ions are as: Conductivity (216-399 μS cm−1), pH (8.2-8.58), NO2- (0.015-0.045 mg dm-3), NO3- (0.01-1.1 mg dm-3), Cl- (1.55-2.95 mg dm-3) and SO42- (4.2-9.2 mg dm-3). Results obtained by the box plot method showed the regions with determined anomalous element concentration values in the water of Lumbardhi Peja. Even that in Kosovo we don’t have yet any legislative convent for allowed concentrations of toxic metals for natural water resources, the results from this study are a small contribution to gain a clear overview of the statement in this field of environmental quality assurance.
Keywords: water, Lumbardhi River, pollution assessment, heavy metals, physico-chemical parameters, ICP/MS
Khimiya. 24, 776-793 (2015) Author(s): M. Kirova, N. Kostova, M. Trendafilova:
Abstract.The integration of information and communication technology (ICT) in the classroom largely depends on teachers. Their competencies and attitudes determine the opportunities for enhancing of learning quality through computer technology application. This article includes study results on views and beliefs of 79 Bulgarian chemistry school teachers in two directions: ICT applications in schools and in chemistry lessons in particular; chemistry teachers’ competencies for ICT integration in the classroom. The data have been collected by focus-group interview and they have been processed by content analysis. The results shown that teachers in the sample are familiar with the possibilities of ICT application and have sufficient technological knowledge and skills, which they combine with their subject knowledge to use technology for presentation and visualization of the chemistry content. The study results did not reveal teachers attitudes for using computer technology in chemistry classes in respect to: problem solving; improvement of student communication and collaboration; development of critical thinking and creativity. Research conclusions point at the need for additional training for chemistry school teachers to identify the opportunities of ICT in order to improve learning and to develop students’ key skills for the digital society.
Keywords: ICT teacher competencies, teacher е-competences, science education, chemistry education, TPACK