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Effects of biodiesel obtained from safflower and sunflower oil on engine performance and exhaust emissions
Get PDFBu araştırmada, aspir ve ayçiçek yağlarından transesterifikasyon yöntemi kullanılarak biyodizeller üretilmiştir. B10 (%5 aspir, %5 ayçiçek biyodizelleri) ve B20 (%10 aspir, %10 ayçiçek biyodizelleri) hacimsel olarak oluşturulmuştur. Dizel, B10 ve B20 yakıtlarının yakıt analizleri yapılmıştır. Deney yakıtlarının motor performansına etkileri ve SCR'nin NOx emisyonları üzerindeki etkisi incelenmiştir. B10 ve B20 yakıtlarının kullanımı ile motor gücünde dizel yakıtına göre sırasıyla ortalama olarak %1,80 ve %3,24 azalma gözlenmiştir. Efektif gücün B10 ve B20 yakıtları ile sırasıyla dizele göre %0,62 ve %1,75 oranında azaldığı gözlemlenmiştir. Özgül yakıt tüketimi incelendiğinde 2000 d/d'da B10'da %3,37 ve B20 de %5,54 artış gözlemlenmiştir. SCR sonrasında 2400 d/d'da sırasıyla dizel, B10 ve B20 yakıtlarında %71,4, %89,4 ve %93,1'lik düşüş gözlemlenmiştir.In this research, biodiesels were produced from safflower and sunflower oils by using transesterification method. B10 (5% safflower, 5% sunflower biodiesels) and B20 (10% safflower, 10% sunflower biodiesels) were formed volumetrically. Fuel analyses of diesel, B10 and B20 fuels were performed. The effects of test fuels on engine performance and the effect of SCR on NOx emissions were investigated. With the use of B10 and B20 fuels, an average of 1.80% and 3.24% decrease in engine power was observed compared to diesel fuel, respectively. It was observed that the effective power decreased by 0.62% and 1.75% with B10 and B20 fuels, respectively, compared to diesel. When the specific fuel consumption was examined, an increase of 3.37% in B10 and 5.54% in B20 was observed at 2000 rpm. After SCR, 71.4%, 89.4% and 93.1% decreases were observed at 2400 rpm for diesel, B10 and B20 fuels, respectively
An investigation on the use of pıaneta blu marble quarried in the Denizli region in interior wet spaces
No full textBu tez çalışmasında, Denizli ilinde bulunan mermer ocakları incelenmiştir. Çal Kısık Kanyonu’ndan çıkarıldığı belirlenen “Pianeta Blu” ticari isimli mermerin laboratuvar testleri, Afyon Kocatepe Üniversitesi Doğal Taş Analiz Laboratuvarı’nda gerçekleştirilmiştir. Mermerin mekanik özellikleri, pandül cihazları da kullanılarak toplamda on farklı test yöntemiyle değerlendirilmiştir. Kayma direnci, buhar geçirgenliği, asitlere karşı dayanıklılık ve sertlik gibi kriterler doğrultusunda, söz konusu mermerin ıslak hacim uygulamaları için uygunluğu araştırılmıştır. Uygulanan testler sonucunda, mermer numunelerinin boyut ve adetlerinin, test türüne bağlı olarak değişiklik gösterdiği tespit edilmiştir. Test sonuçlarına göre Pianeta Blu mermerinin ıslak hacimlerde duvar yüzeylerinde rahatlıkla kullanılabileceği; ancak zemin uygulamalarında, özellikle ıslak alanlarda, ilave yüzey işlemlerinin gerekli olduğu sonucuna varılmıştır. Travertenleriyle ünlü olan Denizli ilinin mermer potansiyelini ortaya koymak, bu bölgedeki mermerle ilgili çalışmaları artırmak ve gelecekte yapılacak araştırmaları teşvik etmek, bu çalışmanın temel amacı olmuştur.In this thesis study, marble quarries located in Denizli, Turkey, were investigated. Tests were conducted on a type of marble called Pianeta Blu, which was identified as being extracted from the Çal Kısık Canyon. These tests were carried out at the Natural Stone Analysis Laboratory of Afyon Kocatepe University. The mechanical properties of the marble were examined through ten different tests, some of which utilized pendulum equipment. Characteristics such as slip resistance, water vapor permeability, acid resistance, and hardness were assessed to determine the suitability of the marble for use in wet areas. According to the test results, the dimensions and quantities of the marble samples varied depending on the type of test performed. The findings indicated that Pianeta Blu marble is highly suitable for use on wall surfaces in wet spaces. However, for flooring applications—especially in wet environments—additional surface treatments are required. The primary aim of this study is to highlight the value of Denizli’s marble, alongside its well-known travertines, to contribute to the growing body of research on the region's natural stones and to encourage further studi es in this area
Matrisler politopunun gürbüz D-kararlılığı üzerine
No full textIn this study, the robust D-stability of a matrix polytope, defined
as the convex hull of a finite set of D-stable matrices, is
considered. A sufficient condition for the robust D-stability of
the matrix polytope is derived for the region D ⊂ C defined as
quadratic matrix inequalities (QMI). This condition is given by
linear matrix inequalities (LMIs). The solution of the LMIs is
addressed by optimizing the maximal eigenvalue function of
symmetric matrices using convex optimization methods.
Illustrative examples are provided to demonstrate the practical
applications of the proposed stability condition.Bu çalışmada, sonlu sayıda D-kararlı matrislerin konveks zarfı
şeklinde verilen bir matris politopunun gürbüz D-kararlılığı ele
alınmıştır. D ⊂ C bölgesi, kuadratik matris eşitsizlikleri (KME) ile
tanımlanan bir bölge olmak üzere, matrisler politopunun gürbüz
D-kararlılığı için bir yeter koşul elde edilmiştir. Bu koşul doğrusal
matris eşitsizlikleri (DME) ile verilmiştir. DME’lerin çözümü
konveks optimizasyon yöntemleri kullanılarak simetrik
matrislerin maksimal özdeğer fonksiyonunun optimize
edilmesiyle ele alınmıştır. Kararlılık koşulunun uygulamaları
açıklayıcı örneklerle verilmiştir
Evaluation of fresh and hardened properties of cementitious composites modified with bis(2-ethylhexyl) succinate biopolymer
No full textBiopolymers derived from biomass recycling instead of petroleum-derived polymers can be the key to sustainable concrete design, reducing building loads and carbon dioxide emissions. Bis(2-ethylhexyl) succinate (BES) is an important option for structural design because it is a bio-based plasticizer, performs well at low temperatures, gels rapidly with water, and has low viscosity and low volatility. This study was undertaken to investigate the effect of incorporating BES into cementitious composites on the macro- and microstructural properties of mortars. The polar long-chain alkoxy functional groups in the structure of BES have significantly increased the hydrate product content by retaining the water molecules on the surface. In addition, due to the gelling ability of BES and its interaction with the hydrated product, the addition of 5 % BES resulted in a 38.14 % increase in compressive strength and a 55.04 % increase in flexural strength. The microstructural analysis confirmed that BES was responsible for accelerating the formation of hydration products. These results demonstrate that BES can be used as a green plasticizer additive alternative for building materials
Therapeutic potential of morin hydrate in methotrexate-induced liver in experimental rats: regulation of organ function and alleviation of oxidative stress
No full textPurpose: Methotrexate (MTX) is an antineoplastic agent with a wide clinical use. However, its complications tissues cause limitations. The effects of many compounds have been studied in reducing the toxicity of MTX in liver tissue. There are limited studies on the elimination of this damage with morin hydrate (MH) flavonoid. In this study, we investigated the effect of MH in MTX-induced hepatoxicity with a focus on oxidative stress. Materials and Methods: In the experiment, 32 female rats were grouped as Control, MTX, MH, MTX+MH (n=8). On the first day of the study, MTX 20 mg/kg single dose was administered ip. MH was administered 100 mg/kg by gavage for 10 days. On the 11th day, biochemical and histopathological analyses were performed on liver tissues from rats. All data were presented with statistical comparison. Results: Serum AST, ALT and LDH levels were highest in the MTX group and lower in the MTX+MH group. MH increased glutathione peroxidase (GPX), reduced glutathione (GSH) and total antioxidant capacity (TAC) levels, but had no regulatory effect on superoxide dismutase (SOD) level. Additionally, MH significantly lowered malondialdehyde (MDA) levels and reduced total oxidant capacity (TOC). Histopathological findings included inflammation, congestion, degeneration, mononuclear cell clusters and dead cells. Tissue damage was most severe in the MTX group, whereas these effects were attenuated in the MTX+MH group. Conclusion: Our results indicated that MH may be potential therapeutic agent in MTX-induced acute liver injury
Sensitivity of the Load-Velocity Relationship Variables to Discriminate the Level of Fatigue Induced by Multiple Sets of the Hexagonal Barbell Deadlift Exercise
Get PDFSenturk, D, Akyildiz, Z, Janicijevic, D, and Garcia-Ramos, A. Sensitivity of the load-velocity relationship variables to discriminate the level of fatigue induced by multiple sets of the hexagonal barbell deadlift exercise. J Strength Cond Res 39(4): 407-413, 2025-This study aimed to evaluate changes in load-velocity (L-V) relationship variables (L-0, v(0), and A(line)) after different fatigue protocols and to determine their correlation with changes in 1 repetition maximum (1RM). After determining the hexagonal barbell deadlift (HBD) 1RM, 27 resistance-trained men randomly completed 3 sessions that only differed in the activity performed between 2 incremental loading tests that were performed at the beginning (presession) and end (postsession) of the session: (a) control protocol: no training; (b) moderate-fatigue protocol: 5 sets of the HBD exercise at 70% 1RM performing half the maximum possible number of repetitions; and (c) high-fatigue protocol: 5 sets of the HBD exercise performed to failure against the 70% 1RM. Significance was set at an alpha level of 0.05. The reduction of 1RM (p < 0.001), v(0) (p = 0.014), and A(line) (p < 0.001) at postsession was greater for the high-fatigue protocol, followed by the moderate-fatigue protocol, and finally the control protocol. The changes in L-0 did not differ between the fatigue protocols (p = 0.372). The percent change in the 1RM at postsession was significantly correlated with the percent change in A(line) (r = 0.714) and L-0 (r = 0.540), but not with the percent changes in v(0) (r = 0.177). These results suggest that the L-V relationship variables offer a highly sensitive and practical solution for fatigue monitoring.National Natural Science Foundation of China; [12250410237]This work was supported by the National Natural Science Foundation of China under Grant 12250410237. The authors thank all the athletes who selflessly gave their maximal effort to participate in this study
New GPS-derived velocity field for Marmara region: Implications for the kinematics along the North Anatolian Fault Zone
No full textThe North Anatolian Fault Zone (NAFZ) is a major strike-slip fault system accommodating the relative motion between the Anatolian and Eurasian plates, extending approximately 1200 km from eastern Turkey to the Aegean Sea in the west. Despite several large earthquakes along the NAFZ during the last century, the northern strand beneath the Sea of Marmara has been seismically silent since the 1766 events, raising concerns about future seismic hazards. The similar to 160-km-long seismic gap, bounded by the 1912 and 1999 ruptures, is considered to have a potential nucleation for a future M > 7 earthquake due to significant strain accumulation over the past two centuries. While previous studies have provided valuable insights into the geometry and deformation patterns of the NAFZ in the Marmara region, discrepancies remain regarding the fault coupling and slip behavior of its submarine segments. The sparse onshore geodetic data, particularly on the northern side of the fault, and limited offshore geodetic observations hinder the ability to entirely resolve fault kinematics and slip characteristics along the northern strand in the Sea of Marmara. To address these limitations, we established a high-spatial-resolution GPS network with both permanent stations and benchmarks, enabling a better understanding of the submarine segment's behavior and seismic potential by investigating the interseismic deformations along the NAFZ segments beneath the Sea of Marmara. Using the recent interseismic GPS velocities, we applied a block model inversion to estimate fault slip rates and coupling ratios along the northern strand of the NAFZ. The checkerboard tests indicate the robustness of our results. This study provides new geodetic constraints that improve our understanding of the seismic potential of the NAFZ beneath the Sea of Marmara, offering critical insights for seismic hazard mitigation in the I(center dot)stanbul metropolitan area.TelluS program of the Institut National des Sciences de l'Univers (INSU); CNRS; Coordinatorship of Scientific Research Projects (BAP) of Hitit University [ODMYO19001.15.002]The authors would like to thank all participants (Emilie Klein, Mehmet Nurullah Alkan, Volkan Ozbey, Turan Erden, Zafer Kose, Kayhan Aladogan, Nurullah S,en, Melih Yamac, Mehmet Atasoy), who helped during the field studies. We also appreciate Tekirdag Metropolitan, Corlu and Marmara Ereglisi municipalities, TUSAGA-Aktif, ISKI-UKBS and Fuat Agalday for their support. We are very grateful to the two anonymous reviewers for their constructive comments and suggestions, which significantly improved the quality of this manuscript. We also thank the Editor for his efforts in handling this manuscript. This study was financially supported by the TelluS program of the Institut National des Sciences de l'Univers (INSU), CNRS and Coordinatorship of Scientific Research Projects (BAP) of Hitit University (project no. ODMYO19001.15.002). The Generic Mapping Tools (GMT) software was used to plot the figures in this manuscript (Wessel et al., 2019)
The Self-Regulation Skills Usage Scale in EFL Learning: Development and Validation
No full textSelf-regulation skill is the ability of an individual to plan, monitor, evaluate, and modify their learning process when necessary. It is highly important in foreign language learning because learning a language requires long-term motivation, discipline, and a strategic approach. This study aims to determine the level of high school students' use of self-regulation skills in EFL learning. The scale consists of six items with factor loadings ranging from 0.427 to 0.749 in the first factor (self- awareness), five items with factor loadings ranging from 0.490 to 0.857 in the second factor (planning), five items with factor loadings ranging from 0.573 to 0.730 in the third factor (reviewing), six items with factor loadings ranging from 0.514 to 0.783 in the fourth factor (using learning strategies), four items with factor loadings ranging from 0.671 to 0.818 in the fifth factor (self-evaluation), and four items with factor loadings ranging from 0.595 to 0.741 in the sixth factor (organizing the learning environment). The Cronbach's alpha coefficients of the scale were calculated as 0.946. As a result of the research, it can be said that a valid and reliable scale with 30 items, six sub-dimensions, and a five-point Likert type was obtained. This scale for gathering information on the self-regulation skills of high school students may guide English teachers in refocusing their teaching practices
The kinematic analysis and pid control of a 6-axis robotic arm
Get PDFRobotlar, bağımsız olarak algılayabilen, düşünebilen, planlayabilen ve hareket edebilen araçlardır. Görevleri bağımsız olarak yerine getirmenin yanı sıra, insan yeteneklerini de genişletebilir. Robotik alanında son yıllarda büyük gelişmeler yaşanmıştır. Robotlar daha akıllı hale gelmiş, karmaşık görevleri yerine getirebilecek kapasiteye ulaşmış ve çok çeşitli uygulamalarda yaygın olarak kullanılmaya başlamıştır. Bu gelişmeler hayatımızda büyük değişimlere yol açmıştır. Robotlar artık profesyonel ve kişisel hayatımızın ayrılmaz bir parçasıdır. Robotik endüstrisi modern dönemde büyük bir gelişmeye sahne olmuştur. Elektronik, sensörler ve yapay zeka gibi teknolojilerdeki gelişmeler sayesinde robotik alanında büyük ilerlemeler kaydedilmiştir. Bu dönemde robotlar, fabrikalarda, hastanelerde ve askeriyede kullanılan robotlar gibi, bağımsız olarak görev yapması mümkündür. Robotik sektörü, daha akıllı hale getirilerek, görevleri daha bağımsız bir şekilde yerine getirebilme hedefiyle sürekli bir gelişim içerisindedir. Robotlar, hem profesyonel hem de kişisel hayatımızda çeşitli alanlarda insan hayatını büyük ölçüde değiştirmektedir. Robotlar, endüstri, tıp, eğitim, eğlence, güvenlik, lojistik, tarım, araştırma ve geliştirme gibi profesyonel hayatımızdaki çeşitli alanlara girmiştir. Bilim, uzay, inşaat, temizlik, sterilizasyon, alışveriş, teslimat, çeviri ve yüz tanıma, renk ve hareket analizi gibi benzer alanlarda ilerlemiştir. Bu tez çalışmasında ABB şirketinin modellediği altı serbestlik dereceli IRB 1200 modeli robot kolun katı modeli tasarlanmasının ardından Matlab/Simulink ortamına aktarılmıştır. Matlab/Simulink ortamında hedef noktalar belirlenmiştir yörünge haline getirilmiştir, bu konumlar homojen dönüşümünden geçtikten sonra her robot eksenine açı gereksinimlerini belirlemek için ters kinematik çözüm bloğuna aktarılır, ters kinematik bloğu ise DC motorlara aktarılır, daha sonra Matlab/Simulink ortamına aktarılan IRB 1200 modeli robot kolun eklemlerine açı gereksinimleri iletilir ve son olarak konum bilgisi edinmek üzere ileri kinematik bloğuna iletilir. Ancak aynı değerde olmayan giriş ve çıkış bilgileri gözlemlenmesinin ardından kontrol sistemi eklenerek sistemin yanıtını referans sinyaline yaklaştırılmış, kontrol sistemi için denetleyici olarak P.I.D seçilmiş ve her bir eklem için ayrı sistem kontrol bağlanmıştır. Robot kol konum kontrolü bu şekilde sağlanmıştır. Sistem yanıtı sırasında oldukça düşük hatalar ve referans konumlara yakın sonuçlara varılmıştır. 2025, xii + 74 sayfa Anahtar Kelimeler: Robot manipülatörü, İleri kinematik, Ters kinematik, Motor kontrol sistemi, Simulink, Homojen dönüşümü, Robot kolu.Robots are equipments that can perceive, think, plan and move independently. In addition to performing tasks independently, they can also expand human capabilities. There have been great developments in the field of robotics in recent years, robots have become smarter, have reached the capacity to perform complex tasks and have begun to be widely used in a wide variety of applications. These developments have led to great changes in our lives and robots have now become an integral part of our professional and personal lives. The robotics industry has witnessed great development in the modern era. Great progress has been made in the field of robotics thanks to developments in technologies such as electronics, sensors and artificial intelligence. During this period, robots have become able to perform tasks independently, such as robots used in factories, hospitals and the military. The robotics sector is in constant development with the goal of becoming smarter and being able to perform tasks more independently. Robots have greatly changed human life in various areas, both in our professional and personal lives. Robots have entered various areas in our professional lives such as industry, medicine, education, entertainment, security, logistics, agriculture, research and development. Science, space, construction, cleaning, sterilization, shopping, delivery, translation and facial recognition. It has advanced in areas such as voice, text, shape, color, motion analysis and similar areas. In this thesis study, the solid model of the six-degree-of-freedom IRB 1200 model robot arm modeled by ABB company was designed and then transferred to the Matlab/Simulink environment. In the Matlab/Simulink environment, certain positions were determined and turned into trajectory, after these positions passed through the homogeneous transformation, they were transferred to the inverse kinematics solution block to determine the angle requirements for each robot axis, the inverse kinematics block was transferred to the DC motors, then the angle requirements were transmitted to the joints of the IRB 1200 model robot arm that we transferred to the Matlab/Simulink environment and finally transmitted to the forward kinematics block to obtain position information. However, it was observed taht input and output information that were not at the same value, then the control system was added, P.I.D was selected as the controller and a system control was connected for each joint. The robot arm position control has been achieved in this way and very low errors and results close to the reference positions were observed. 2025, xii + 74 pages Keywords: Robot Manipulator, Forward Kinematics, Inverse Kinematics, Motor Control System, Simulink, Homogeneous Transformation, Robot Arm
Infliximab ameliorates vancomycin-triggered nephrotoxicity: Biochemical, molecular, and histopathological insights
Get PDFThis study investigated the pathophysiological effects of vancomycin (VCM)-induced nephrotoxicity and the potential protective role of infliximab (INF). Twenty-eight male Wistar Albino rats (200 +/- 20 g) were randomly divided into four groups (n = 7): Control, INF, VCM, and VCM + INF. The Control group received physiological saline; the INF group received a single intraperitoneal (i.p.) dose of 7 mg/kg INF; the VCM group received 200 mg/kg VCM (i.p., twice daily for 7 days); and the VCM + INF group received INF 24 h prior to VCM administration. Body weight and kidney index were recorded. Serum BUN and creatinine, and renal tissue levels of MDA, SOD, and GSH were measured. Gene expression levels of Akt1, Nrf2, HO-1, Bax, Bcl-2, Caspase-3, Beclin1, Hsp27, and Hsp70 were analyzed by qRT-PCR. Histopathological evaluation was performed using hematoxylineosin staining, while apoptosis was assessed by immunohistochemical staining of cleaved caspase-3. VCM significantly reduced body weight, increased kidney index, and elevated BUN, creatinine, and MDA levels, while reducing SOD and GSH. INF treatment significantly reversed these effects. VCM also upregulated pro-apoptotic, autophagy, and stress response genes, while downregulating anti-apoptotic and antioxidant genes; these changes were significantly corrected by INF. Histopathological analysis showed tubular damage and inflammation in the VCM group, ameliorated by INF. Cleaved caspase-3 expression increased with VCM but was suppressed by INF. These findings indicate that infliximab provides multifaceted protection against VCM-induced kidney injury by modulating oxidative stress, apoptosis, and autophagy. This reno-protective potential of INF can be considered a novel therapeutic strategy for VCM-induced nephrotoxicity.Scientific Research Projects Commission of Sivas Cumhuriyet University [V-2024-138]This project was supported by the Scientific Research Projects Commission of Sivas Cumhuriyet University as a Rapid Support Project with project number V-2024-138