Osmanlı Devleti, tarih sahnesine çıktığı andan başlamak üzere özellikle ciddi problemlerle karşı karşıya kaldığı 19. yüzyıla kadar tarikatlara, belirli bir özgürlük anlayışı çerçevesinde, sahip ...oldukları önemli işlevleri sebebiyle, gelişme ve büyümelerine izin vermiştir. Ancak Safevi tehlikesinin yükselişe geçtiği ve merkezileşmenin ağırlığını giderek hissettirmeye başladığı zaman dilimlerinde tarikatlar üzerindeki denetimini de artırmıştır. Bu denetimin artmasına paralel olarak 19. yüzyılla beraber dönemin getirmiş olduğu yeni şartlar ve Osmanlı Devleti’nin bu şartlara uyum sağlamak için yürüttüğü politikalar; tarikat ve tekkelerin devlet tarafından sağlanan özerk durumdaki statülerini kaybetmelerine sebep olmuştur. Tarikatların devlet tarafından denetim altına alınmalarının önemli bir göstergesi Meclis-i Meşayih’in kurulmasıdır. Şeyhülislamlık tarafından denetlenen dergâhlar, 1866 yılında Şeyhülislamlığa bağlı olarak kurulan Meclis-i Meşayih kurumunun uhdesi altına alınmıştır. Böylece kademeli bir biçimde başlayan tekkeleri kontrol süreci, bir kurumsal yapının ortaya çıkmasını kaçınılmaz hale getirmiş ve bu durumun bir sonucu olarak Meclis-i Meşayih kurularak çalışmalarına başlamıştır. Tekke ve zaviyelere ait tüm işler ve özellikle şeyh atamalarından sorumlu olan Meclis-i Meşayih, tekkelerin kontrol altına alınması açısından da önemli bir konum elde etmiştir. Bu çalışmada Osmanlı Devleti’nin tarikatlarla olan ilişkisinde Meclis-i Meşayih’in amacı, önemi ve kararları nelerdir sorusuna cevap aranacaktır. Anahtar Kelimeler: Din Sosyolojisi, Dini Gruplar, Tarikat, Devlet-Tarikat İlişkisi, Meclis-i Meşayih.
Efficiency is a concept that evaluates the optimal utilization of resources, including time, energy, finances, or materials, in order to accomplish a particular goal or objective. As widely ...acknowledged, energy losses occur in systems involving relative motion between interacting machine elements due to friction. In the case of a gearbox, these losses can arise from tooth friction in the gear mechanism, friction in sealing elements, friction in roller bearings, and the influence of the lubricant used in the system, all of which are subject to environmental conditions. This study aims to experimentally determine the efficiency of the gearbox under various operating conditions by considering the gearbox as a comprehensive system encompassing all its components. A measurement system was designed in order to obtain the efficiency of a gearbox. Experiments and measurements were carried out via software support. The measurement system contains two torque transducers, electrical resistive load device, an electrical motor with temperature measurement thermocouple, and two stage helical gearbox. In experiments conducted through computer commands, input revolutions were incrementally increased with 400 rpm intervals within the range of 700–2700 rpm. Moreover, experiments were carried out at different lubricant levels in the gearbox. At the same time lubricant temperature was measured and effects to the gearbox efficiency were investigated. Subsequently, different lubricant with distinct viscosity indices were employed. As a result of this experimental design, regime efficiency values were obtained for each case. Thus, power loss of the gearbox system has been determined. These results were examined using a general full factorial design. Analysis of variance (ANOVA) tables were created and the effects of the parameters on the system and the efficiency results were determined by checking whether the parameters were interacting or not. Finally, regression analysis was performed and the regression function was obtained in order to develop a predictive model to estimate the efficiency of a gearbox.
Herein, Cs2AgBiBr6 particles produced by the traditional super-saturation precipitation method were used as precursors to create Cs2AgBiBr6 films by the gas-quenching process under ambient ...atmospheric conditions. These films were utilized as a light-absorbing layer in hole-transporting free perovskite solar cells (PSCs) with carbon electrodes. Furthermore, the incorporation of the 1-butyl-3-methylimidazole hexafluorophosphate (BMIMPF6) ionic liquid (IL) at the metal oxide electron transporting layer/perovskite interface resulted in enhanced crystallinity of the perovskite, forming large perovskite grains of up to 800 nm. However, it was discovered that establishing the optimal concentration for passivating surface defects takes precedence over encouraging the growth of larger perovskite grains. The utilization of the optimized BMIMPF6 concentration led to a remarkable increase in the power conversion efficiency (PCE) of the cell, with a boost of over 31% to reach 1.67%, when compared to the cell produced without the inclusion of the IL. Our findings underscore that the passivation of surface defects between the TiO2 and perovskite layers holds more importance for enhancing the PCE of Cs2AgBiBr6-based perovskite solar cells than focusing solely on the perovskite morphology.
Tetragonal BaTiO3 nanoparticles have been hydrothermally synthesized using the electrospun TiO2 nanofibers as the Ti-source. Microstructural and compositional analyses have been carried out using ...XRD, SEM, TEM, XPS, and Raman spectroscopy. Characterization studies confirmed that the BaTiO3 nanoparticles had a tetragonal structure with an average particle size of 100 nm. Photocatalytic activities of the nanoparticles were investigated via the decolorization of methylene blue dye aqueous solutions under visible light and UV-A irradiations. The degradation efficiency reached to 13 and 35% after exposing to light for 60 min with visible and UV-sources, respectively. Effect of sintering temperatures on the dielectric properties was also investigated. Among all the sintering temperatures employed, 1473 K was the optimum sintering temperature for these ceramics in terms of high relative density (95.3%), high dielectric constant (3162 at 1 MHz), and low loss tangent (15 × 10−3 at 1 MHz). Experimental results showed that electrospun TiO2 fibers can be used as a precursor template to produce nano-scale BaTiO3 particles which are suitable for various applications such as photocatalysis and capacitors.
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•BaTiO3 nanoparticles were produced from electrospun TiO2 nanofibers for the first time.•BaTiO3 exhibited tetragonal symmetry and 100 nm average particle size.•Hydrothermally derived nanoparticles were used for two different applications.•BaTiO3 nanoparticles used as photocatalyst for photodegradation of methylene blue.•Microstructure and dielectric properties of sintered BaTiO3 ceramics were studied.
In this study, for the first time, n-i-p PSCs were fabricated using dopant-free 2,7-dioctyl1benzothieno3,2-
b
1benzothiophene (C8-BTBT) as the solution-processed hole transporting layer (HTL). The ...power conversion efficiency (PCE) of the optimized device with the C8-BTBT film that favored edge-on molecular alignment was 22.45% with negligible hysteresis. A thinner dopant-free C8-BTBT HTL effectively protected the perovskite layer from moisture resulting in better shelf-life stability for un-encapsulated PSCs, which maintained >80% of its initial PCE (after a period of 120 days) at a relative humidity level of 40-45%. In addition, the C8-BTBT-based PSCs kept their high performance with no obvious PCE loss at 60 °C for 20 days in the ambient atmosphere and retained 82% of their initial PCE at 85 °C for 10 days. Overall, our findings revealed that a thin solution-processed C8-BTBT HTL plays a critical role not only in hole extraction and transport but also in greatly improving the ambient and thermal stability of n-i-p PSCs.
Herein, we have demonstrated n-i-p PSCs with an efficiency of 22.45% and high thermal stability using dopant-free 2,7-dioctyl1benzothieno3,2-
b
1benzothiophene (C8-BTBT) as the solution-processed hole transporting layer (HTL).
In this study, TiO2 nanofibers were fabricated via the electrospinning method followed by air annealing. Then, Ti‐requirement in the conventional hydrothermal synthesis of BaTiO3 stoichiometry was ...supplied by using these nanofibers. The microstructural and compositional properties of BaTiO3 nanoparticles were studied using SEM, TEM, XRD, XPS, and Raman spectroscopy. The structural analysis showed that the cubic symmetry was the dominant one in the BaTiO3 nanoparticles, whereas Raman spectroscopy indicated the coexistence of cubic symmetry with the tetragonal polymorph. The nanoparticles displayed higher photocatalytic reactivity under UV‐A light compared to visible irradiation during decomposition of methylene blue dye and reached 24.2% and 18.8% degradation, respectively, after 1 hour. Furthermore, the dielectric properties were investigated using sintered compacts of these nanoparticles. Among the employed temperatures for sintering, the highest relative density (90%) and dielectric constant (2165 at 1 MHz) were obtained at 1250°C and 5 hours. This study revealed that the electrospun TiO2 nanofiber precursor can successfully be used for the production of nanoscale barium titanate particles suitable for various applications.
Herein, Cs2AgBiBr6 double perovskite films, which is considered one of the alternative materials to organic–inorganic Pb‐based perovskites in terms of toxicity and stability, are fabricated by ...gas‐quenching approach in ambient environment for the first time. Moreover, the study examines the effect of gas flowing rate on the solvent evaporation rate, crystallinity, morphology, and optical properties of the perovskite. The results indicate that the duration of color change from transparent to shiny yellow during gas quenching of Cs2AgBiBr6 films is influenced by the gas flowing rate, and this parameter has a notable impact on the properties of the films. In addition, incorporation of the gas‐quenched Cs2AgBiBr6 thin films in perovskite solar cells leads to 1.47% power conversion efficiency with open‐circuit voltage of 1.04 V, short‐circuit current density of 2.11 mA cm−2, and fill factor of 67.4%. Overall, this study provides a new approach to fabricate Cs2AgBiBr6 thin films in ambient atmosphere for potential optoelectronic applications.
Gömülü Teori, sosyal bilimler alanında yapılan çalışmalarda teorik olarak toplanan verilerin analiz edilmesi yöntemiyle sistematik boyut kazanan bir metodolojidir. Bu metodolojik yaklaşımda, sonuca ...ulaşma biçimi olarak tümdengelim modelinin yerine, tümevarımsal akıl yürütme modeli kullanılır. Gömülü Teori ile yapılan çalışmalar ağırlıklı olarak bir soru ile, hatta bazen yalnızca nitel verilerin toplanmasıyla başlamaktadır. Araştırmacılar toplanan verileri analiz ederken, tekrar eden düşünce, kavram veya öğeleri belirtir ve bu unsurlar verilerden elde edilen kodlarla etiketlenir. Daha fazla veri elde edilip çalışma tekrar kontrol edildikçe kodlar; kavram ve daha sonra kategorilere ayrılabilir.
Böylece yeni bir teorinin temelleri atılmış olur. Bu nedenle, Gömülü Teori, araştırmacının mevcut bir teorik çerçeveyi seçtiği ve ancak o zaman teorinin incelenen fenomene nasıl uygulandığını veya uygulanmadığını göstermek için veri topladığı geleneksel araştırma modelinden oldukça farklıdır. Yani yapılan çalışmalarda elde edilen sonucu mevcut teoriler açıklayamadığı veya açıklamada yetersiz kaldığı durumlarda Gömülü Teori ile yeni bir teori elde edilmiş olmaktadır. Bu anlamda Gömülü Teori bir teori olmaktan çok yeni bir teorinin çıkışına zemin hazırlayan metodolojik bir yöntem olarak karşımıza çıkmaktadır.
Bu çalışmada Gömülü Teori’nin metodolojik boyutu bilgiye nasıl ulaşabileceğine ilişkin; “Araştırmanın amacı nedir?/ Araştırma yöntemi nasıl olmalıdır?/ Araştırmacının rolü nedir - ne olmalıdır? Değerlerin rolü nedir?/ Araştırma raporunun dili nasıl olmalıdır?” sorularına verilecek cevaplar üzerinden ele alınacaktır. Ayrıca Gömülü Teori’nin tarihçesi ve uygulama biçimi gözden geçirilerek bu teorinin Din Sosyolojisi çalışmalarına ne şekilde taşınıp taşınamayacağı tartışılacaktır.
Objectives: Degenerative lumbar spinal stenosis (DLSS) is the leading cause of pain, disability, and loss of independence in older adults. In this study, the relationship between DLSS and ...paravertebral muscle thickness and density was investigated using computed tomography (CT) and magnetic resonance imaging (MRI) methods. Thus, the importance of muscles has been examined to take precautions in the name of preventive medicine.
Methods: This study was planned as a cross-sectional study. The patient group (n = 77) who had surgery for DLSS and the control group (n = 77) were examined. A total of 154 participants (55 females and 22 males in each group) were evaluated retrospectively in terms of cross-sectional area (CSA) and density in the psoas, erector spina and multifidus muscles. In both groups age, gender and body mass index values equalized. Measurements was averaged from the mid-lumbar 3 level from both sides and multi-points.
Results: There was no significant difference between muscle thicknesses (p > 0.05). When evaluated in terms of muscle densities, a significant difference was found between the patient and the control group in terms of psoas muscle (p < 0.05). Likewise, there is the same relationship between erector spinae muscle density and multifidus muscle density (p < 0.05).
Conclusions: Roughly no difference was found between the patient and control groups in terms of CSA of the psoas, erector spinae and multifidus muscles, but it was observed that the muscle density, especially in the multifidus, decreased significantly in the patients. Our results suggest that paravertebral muscle density assessment is an important criterion in disease prediction and can inform preventive treatment.
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