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Öğe English prepositions as function words are not as easy for language learners as normally supposed to be(Batman Üniversitesi, 2022-06-30) Yaş, EminPrepositions as function words and single monomorphemic words are the most basic words of the human language, especially in the context of maintaining daily life. They are probably the first lexes/words entered to the human’s linguistic repertoire, as their requirements in the language are so essential. Prepositions shows various relationships between lexes or phrases in sentences. Among these relationships time, points, position, direction and various degrees of mental or emotional attitudes seem to be significant. The purpose of the research is try to reveal what kind of challenges English prepositions have for the learners and also to confirm if they are as difficult as some linguists have stated before. Another purpose is to find out which features are more difficult among all their entity properties. The results of this study disclose that English prepositions possess very complex structures, different meanings and an associating duty of various types of part of speeches. In particular, those that construct the phrasal verbs require great effort for learning due to the loss of the meaning (sometimes partially, sometimes completely) they undergo. It has been understood that their properties such as steadily changing meaning and function make them quite difficult elements for learners of English.Öğe An exergy analysis of a concentric tube heat exchanger using hBN-water nanofluids(Inder Science Publishers, 2021) Budak Ziyadanoğulları, Neşe; Perçin, SüleymanThis study investigated the effects of using nanofluids prepared with hexagonal boron nitride (hBN) nanoparticles on the thermal performance and pressure drop of a concentric tube heat exchanger. Experiments were carried out with water-hBN nanofluids for stable, dispersed, 0.01%, 0.1% and 1% volume concentrations, at different flow rates and Reynolds numbers under parallel and counter-flow conditions. When the experimental results were examined, the exergy loss was higher in the parallel-flow heat exchanger compared to the counter-flow heat exchanger. The highest exergy loss value was obtained for distilled water at the highest Reynolds number (Re = 8,700) for parallel flow operation at 170 W. The exergy loss of water at the highest Reynolds number (Re = 8,700) for parallel flow operation increased by 15.7%, 24.8% and 49.8% for hBN-water concentrations of 0.01%, 0.1% and 1%, respectively. Exergy loss of water at the highest Reynold number (Re = 8,700) for counter flow operation increased by 11.3%, 17.3% and 29.2% for hBN-water concentrations of 0.01%, 0.1% and 1%, respectively. When evaluating the exergy analysis of the system, exergy losses due to pressure drops were negligible for both flows (parallel and counter).Öğe Numerical and experimental investigation of solar chimney power plant system performance(Taylor & Francis, 2020-03-15) Karakaya, Hakan; Durmuş, Aydın; Avcı, Ali SerkanA prototype of a solar chimney power plant was performed by modeling in this study. The performed prototype was experimentally confirmed. Temperature, velocity, and radiation values were measured to actualize the confirmation. Experimental data that were obtained to determine the performance of solar chimney whose prototype was actualized by the help of measured values were computationally analyzed. The geometry of a solar chimney in the analysis was bidimensionally (2D) drawn on an axis of symmetry. The numerical simulation was analyzed with computational fluid dynamics (CFD) method. Since analysis results show that there is turbulent flow in system (RNG), k-ɛ turbulence model was used. Continuity, momentum, and energy equations were applied to the solar chimney system via the finite volume method. Moreover, DO (discrete ordinates) model was inserted in analysis to evaluate the radiation effect in the collector area. In addition to all these, correlation results between SPSS 17 statistics program and data obtained were evaluated. Finally, with reference to the comparison between numerical and experimental results, data obtained and numerical data are close to each other; the prototype is applicable to the real systems.Öğe Representations of African Female Identity beyond Border in Buchi Emecheta’s Second-Class Citizen(ECLSS Online 2020b, 2020-06) Işık, EmrahBuchi Emecheta is considered to be one of the most renowned African female writers and she, throughout her writing career, has been a literary pioneer of African women’s struggle in the face of both the colonization by African men and the discrimination based on racial and gender issues. In her second novel, Second-Class Citizen, along with such subject matters as gender, colonialism, patriarchal oppression, Emecheta focuses on cross-bordering, transnational and trans-cultural mobility and female identity formation of Adah setting foot in the centre of the Empire. In this respect, this study intends to examine the transnational movement of Adah from Nigeria to London with regards to gender, migration and conflict between the identity formation of a woman migrant beyond national border and the patriarchal codes, which is symbolized by her husband, Francis. Moreover, the paper discusses the oppression to which the black immigrants get exposed and aims to lead readers throughout the world to gain insight into that problem beyond border.Öğe Effects of ethanol addition to biodiesel fuels derived from cottonseed oil and its cooking waste as fuel in a generator diesel engine(Taylor & Francis, 2020-03) Karakaya, HakanExploration of energy sources such as renewable and non-edible vegetable oils has been continued during the recent two decades of 2000s. Cottonseed oil is a non-edible, abundant oil and is generally used as cooking oil. In the present study, the usability of biodiesel derived from both cottonseed oil and its cooking wastes was investigated by blending them with ULSD or ethanol in 50 percentages. B50, WB50, B50E50 and WB50E50, biodiesel and ethanol-contained fuels and ULSD were prepared for experiments. Combustion, performance, and emissions tests were conducted on a diesel engine used for power-producing electrical generator. In the combustion tests, cylinder pressure, HRR, CHR, MGT, and MFB were analyzed while MFC, BSFC, exhaust manifold temperature, and thermal efficiency were obtained in the performance tests. In the emissions tests, CO, HC, and NOx emissions were measured and compared with the results of ULSD. Combustion and performance findings of ULSD contained biodiesel blends were found more similar to those of ULSD. The duration of combustion stage can clearly be seen to be narrowed for ethanol-contained blend because of the rabid combustion characteristics of ethanol. Besides, the peak of HRR was found 10% higher for B50E50 while it was found averagely 8% for WB50E50 blends. NOx emissions were found 48% lower averagely for ethanol contained biodiesel blends that it is the most important finding of ethanol using with biodiesel. Besides, HC emissions were also found about 75% for biodiesel contained diesel fuel blends.Öğe An experimental investigation of the effect of thermophysical properties on time lag and decrement factor for building elements(Gazi University, 2020-06-01) Oktay, Hasan; Yumrutaş, Recep; Argunhan, ZekiThe time lag (TL) and decrement factor (DF) are essential for the heat storage capabilities of building elements, which strictly depend on the thermophysical properties of the elements. Many investigations are presented in literature arguing to find the influence of each thermophysical property on TL and DF by keeping the other properties constant. This study aims to investigate the effect of each property on TL and DF, utilizing relationships between the measurement values of the thermophysical properties of wall materials. Therefore, first, 132 new concrete wall samples were produced, and their thermophysical properties were tested. Secondly, TL and DF values for each building element are computed from the solution of the problem by Complex Finite Fourier Transform (CFFT) technique. Finally, a multivariate regression analysis has been performed, and the variations of each thermophysical property versus TL and DF are presented, and also the findings are compared with literature. The results show that each property alone (keeping the other properties constant) is not adequate to identify the thermal inertia and thermal performance of a wall element. Besides, 87.3 % decrease in thermal diffusivity corresponds to 6.03 h increase in the value of TL and 88.8 % decrease in value of DF; respectively, for W1 wall assembly.Öğe Performance analysis of temperature changes of fuels used in pem fuel cell(Batman Üniversitesi, 2022-12-31) Demir, Merve; Yılmaz, AdemIn this study, the temperature values of the fuels used in Polymer Electrolyte Membrane (PEM) fuel cell were determined and the optimum temperature ranges were obtained for these fuels. Pure hydrogen and oxygen were used in the anode and cathode portions. In this study, moisture was taken as 40%, hydrogen amount as 0.3 ml/min and oxygen amount as 0.5 ml/min. Line temperature values in the system were also tested between 40-80°C with a 5°C difference. In the experiments carried out at 40°C, when the voltage value was taken as 0.442V and the current value was taken as 1.81A, the power value obtained in the system was found to be 0.804W. In the experiment, when the current value is 1.8A and the voltage value is 0.535V at 75°C, the power value in the system is found to be 1.025W. The lowest W value was calculated as 0.804W at 40°C and the highest W value was calculated as 1.025W at 75°C.Öğe Nurullah Genç’in İntizar adlı romanında Tebliğ ve İlahi Aşk(İksad Yayınevi, 2020-02) Zariç, MahfuzNurullah Genç’in tezli roman olarak kabul edilebilecek İntizar adlı eserinde, akıl, ruh, aile hayatı ve aşk gibi konular ele alınmıştır. Romanda akla ve beşeri aşka karşın imanla özdeşleştirilen İlahi aşk; felsefeye karşın da nas üstün tutulmuştur. İsim ve renk sembolizminden de faydalanılan bu romanda yazar, kurguda mektup ve günlük tekniklerinden, sondan başlama ve geri dönüşler gibi modern ve postmodern anlatım tekniklerinden faydalanmıştır. Romandaki imkânsız aşk kurgusu aracılığıyla, roman merkezi kişilerinden Emre, tasavvufi kavramlar eşliğinde, tebliğ görevinin nasıl olması gerektiğini ve hidayete ermenin ne anlama geldiğini de izah etmiştir.Öğe Seasonal variation of fatty acid composition of trout (Salmo opimus)(Batman Üniversitesi, 2020-06-30) Turgay, ÖzlemThe changes of fatty acid (FAs) composition of muscle tissues of trout (Salmo opimus) caught from Fırnız and Törbüzek in the Ceyhan Basin Region were investigated by using GC. Palmitic acid and oleic acid were the most abundant FAs and significant differences (p<0.05) were observed between seasons. The composition of fatty acids showed that ω-3 poly unsaturated fatty acids (∑ω-3 PUFAs: 6.26-25.44%) were highest, followed by ω-6 (∑ω-6 PUFAs: 5.87-8.24%). The ratio of ω-3/ω6 the samples were ranged from 1.06 to 3.13%. This study showed that the level of total PUFAs (mainly n-3 and n-6 fatty acids) increased significantly during the summer and autumn period in the muscle tissue of brown trout.Öğe Milling Inconel 718 workpiece with cryogenically treated and untreated cutting tools(SpringerLink, 2021-07-17) Gürbüz, Hüseyin; Baday, ŞehmusAlthough Inconel 718 is an important material for modern aircraft and aerospace, it is a kind material, which is known to have low machinability. Especially, while these types of materials are machined, high cutting temperatures, BUE on cutting tool, high cutting forces, and work hardening occur. Therefore, in recent years, instead of producing new cutting tools that can withstand these difficult conditions, cryogenic process, which is a heat treatment method to increase the wear resistance and hardness of the cutting tool, has been applied. In this experimental study, feed force, surface roughness, vibration, cutting tool wear, hardness, and abrasive wear values that occurred as a result of milling of Inconel 718 material by means of cryogenically treated and untreated cutting tools were investigated. Three different cutting speeds (35-45-55 m/min) and three different feed rates (0.02- 0.03-0.04 mm/tooth) at constant depth of cut (0.2 mm) were used as cutting parameters in the experiments. As a result of the experiments, lower feed forces, surface roughness, vibration, and cutting tool wear were obtained with cryogenically treated cutting tools. As the feed rate and cutting speed were increased, it was seen that surface roughness, vibration, and feed force values increased. At the end of the experiments, it was established that there was a significant relation between vibration and surface roughness. However, there appeared an inverse proportion between abrasive wear and hardness values. While BUE did not occur during cryogenically treated cutting tools, it was observed that BUE occurred in cutting tools which were not cryogenically treated. Also, in this study, the statistical validity of the experimental values was tested with the help of secondorder equations and analyses of variance (ANOVA). R2 values obtained as 99.14%, 99.76%, and 97.98% for vibration, surface roughness, and feed force values were modeled statistically with the help of second-order equations, respectively.
