Volume 2, Issue 1, December 1998
CONTENTSThe acylation kinetics of polystyrene with acetic anhydride (1998) Volume(issue) 2(1): 1-12.
H. Kara, Y. Çengeloğlu, R. Kurbanlı, M. Ersöz, and A. Ayar
Department of Chemistry, Faculty of Arts and Sciences, Selçuk University, 42079 Konya, Turkey
The kinetics of acylation reaction of emulsified polystyrene and ethyl benzene as a model compound were investigated with acetic anhydride in the presence of BF3.O(C2H5)2 catalysts. The kinetic parameters of the acylation reaction of polystyrene were compared to that of the model compound. the reaction rate is dependent on the initial concentration of the used compound and catalyst. In addition the reaction parameters such as reaction rate constant (k), the activation energy (Ea) and reaction order were determined and the mechanism of the acylation reaction was purposed.
Stoichiometry in chemistry education (1998) Volume(issue) 2(1): 13-
İ. Ceyhun1, Z. Karagölge1, and H. Saraç2
1Education Faculty, Atatürk University, Erzurum, Turkey
2Department of Chemical Engineering, Atatürk University, Erzurum, Turkey
This paper is specially consideration with the application of the stoichiometry in Chemical education. In General Chemistry Laboratory, KHCO3(s) was given to different student groups. KHCO3(s) was then heated and predict the products of the decomposition. It is found that KHCO3(s) decompose to K2CO3(s), CO2(g) and H2O(g). End of the experiments, student groups selected have leaded to apply the concept in the scientific analysis of a chemical problem.
Liquids from olive husk by using supercritical fluid extraction and thermochemical methods (1998) Volume(issue) 2(1): 17-22.
F. Akdeniz1, M. M. Küçük2, and A. Demirbaş1
1Karadeniz Technical University, Fatih Education Faculty, 61335-Söğütlü, Akçaabat, Trabzon, Turkey; 2Y. Yıl University, Education Faculty, 65080, Van, Turkey.
The supercritical fluid extraction SFE) is suited for the olive husk material. The most effective solvents are acetone for non-catalytic SFE and methanol for NaOH catalytic SFE of the olive husk samples. The yields of SFEs with methanol, ethanol or acetone were 27.4, 41.5 and 43.2 % at 523 K; 40.8, 50.9 and 56.6 % at 563 K; 44.3, 55.1 and 63.0 % at 583 K, respectively. The methanol solubles increased from 27.4 to 49.1 % (at 523 K), 40.8 to 69.2 % (at 563 K) and 44.3 to 84.4 % (at 583 K) with 10.0 % NaOH catalyst.
Teaching practical chemical kinetics of pyrolysis reactions (1998) Volume(issue) 2(1): 23-28.
P. K. 216, 61035 Trabzon, Türkiye
The bio-waste can be pyrolyzed in a simplified fast pyrolysis device.. In the pyrolysis of bio-waste, it was observed that the pyrolysis rate increases with increasing temperature and pyrolysis time. The average values of the pyrolysis parameters were the apparent activation energy (E) 145.8 kJ mol-1, the pre-exponential factor (A) 5.92 x 105 s-1, the reaction order (n) 0.99 and the rate constant (k) 1.51 x 107 s-1 for the pyrolysis process of the bio-waste.
Energy education: Energy concepts and risks of alternative energy
resources in Turkey (1998) Volume(issue) 2(1): 29-42.
P. K. 216, 60335 Trabzon, TURKEY
While studying the concepts of energy in their lesson the chemistry teachers are not in agreement about the teaching methods. Because of this, the energy concepts understood differently among the students. And that the insufficiency of the presentation of energy concepts in the text books, together with mis-ordering of the concepts might be the cause of insufficient understanding of the energy concepts by the sample of the study. The rational use of energy is essential for the long-term sustainability of future generations. Professional diseases and deaths of alternative energy resources in Turkey was studied. The concept of internal entropy relates to inter-atomic or inter-molecular interactions at nonequilibrium of sub-atomic particles.. This is a state of ground unification of the minimal symmetric or maximal disorder of sub-atomic particles.
Experimental and theoretical investigation of combined solar heat pumpsystem for residential heating in Turkey (1998) Volume(issue) 2(1): 43-61.
T. Ayhan and K. Kaygusuz
Mechanical Engineering Department, Karadeniz Technical University, 61080, Trabzon, Turkey
In order to investigation the performance of the combined solar-heat pump system with energy storage in encapsulated phase change material (PCM) packings for residential heating in Trabzon, Turkey, an experimental set up was constructed. Also, a comparative study of the performance of this system has been undertaken theoretically. Simulations have been made with BASIC computer program of three basic combined configurations, as well as conventional solar and conventional heat pump systems in Trabzon by using meteorological data. The experimental results were obtained from December to May during the heating season for four heating systems. These systems are a conventional solar system, a series heat pump system, a parallel heat pump system and a dual source heat pump system. The experimentally obtained results are used to calculate the collector efficiency, heat pump coefficient of performance (COP), seasonal heating performance, the fraction of annual load meet by free energy, storage and collector efficiencies and total energy consumption of the systems during the heating season.