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Öğe The effect of Plantago major Linnaeus on serum total sialic acid, lipid-bound sialic acid, some trace elements and minerals after administration of 7,12-dimethylbenz(a)anthracene in rats(SAGE, 2012-04) Oto, Gökhan; Ekin, Suat; Özdemir, Hülya; Levent, Abdulkadir; Berber, İsmetThe present study was designed to evaluate the effect of Plantago major Linnaeus (PM) extract on serum total sialic acid (TSA), lipid-bound sialic acid (LSA), some trace elements (copper (Cu), zinc (Zn) and iron) and mineral levels (magnesium, calcium and sodium) in Wistar albino rat administrated 7,12-dimethylbenz(a)anthracene (DMBA). Rats were divided into three equal groups (n = 6). Group I comprised the control group, group II was treated with DMBA (100 mg/kg, single dose) and group III was treated with DMBA (100 mg/kg single dose) and aqueous extract of PM 100 mg/kg/day for 60 days. After 60 days, statistical analyses showed that TSA and LSA levels in DMBA and DMBA + PM groups were significantly higher compared to the control group (TSA: p < 0.01, p < 0.05; LSA: p < 0.05, p < 0.05, respectively). Serum Zn levels were decreased in subjects treated with DMBA (p < 0.01) and DMBA + PM (p < 0.05) compared to the control group values. Serum Cu levels were increased in DMBA group and PM-treated group compared to the control group values. The results of this investigation showed that the levels of TSA and LSA changed significantly, which are sensitive markers for detecting the toxic effects of DMBA. On the other hand, observed decline in Zn levels in rats from DMBA + PM group might be due to decreased generation of free radicals and oxidative stress. Results from this study suggest that PM may be partially effective in preventing carcinogenesis initiated by environmental carcinogen DMBA.Öğe Hardness and wear behaviours of al matrix composites and hybrid composites reinforced with B 4 C and SiC(Springer Nature, 2019-01-15) Çelik, Yahya Hışman; Kılıçkap, ErolThe conversion into the desired shape of the metal powders using Powder Metallurgy (PM) method enables economically mass productions. This case allows producing parts with complex and high dimensional accuracy with no machining. In this study the composites and hybrid composites with Al matrix were produced using PM method with different ratios B4C and SiC. Microhardness and wear experiments of the produced composites were investigated. Wear experiments were performed at a constant speed of 0.5 m/s, application loads of 5, 10 and 15 N and sliding distances of 250, 500, and 750 m. Then, SEM images of composites and hybrid composites were captured. The increase of the reinforcement ratio in the composites contributed to the increase of the hardness. The highest hardness value was computed as 58.7 HV from 16% B4C reinforced composite. In addition, the increase in the reinforcement ratio contributed to the increase of the wear resistance. The increase in the load and sliding distance also increased the wear. The minimum weight loss was calculated as 18 mg from 5 N load, 250 m sliding distance and 16% SiC reinforced composite.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 Finite element analysis of the stress distributions in peri-implant bone in modified and standard-threaded dental implants(Taylor & Francis, 2016-01) Topkaya, Tolga; Dündar, Serkan; Solmaz, Murat Yavuz; Yaman, Ferhan; Atalay, Yusuf; Saybak, Arif; Asutay, Fatih; Çakmak, ÖmerThe aim of this study was to examine the stress distributions with three different loads in two different geometric and threaded types of dental implants by finite element analysis. For this purpose, two different implant models, Nobel Replace and Nobel Active (Nobel Biocare, Zurich, Switzerland), which are currently used in clinical cases, were constructed by using ANSYS Workbench 12.1. The stress distributions on components of the implant system under three different static loadings were analysed for the two models. The maximum stress values that occurred in all components were observed in FIII (300 N). The maximum stress values occurred in FIII (300 N) when the Nobel Replace implant is used, whereas the lowest ones, in the case of FI (150 N) loading in the Nobel Active implant. In all models, the maximum tensions were observed to be in the neck region of the implants. Increasing the connection between the implant and the bone surface may allow more uniform distribution of the forces of the dental implant and may protect the bone around the implant. Thus, the implant could remain in the mouth for longer periods. Variable-thread tapered implants can increase the implant and bone contact.Öğe Synthesis, characterization and antioxidant activity of heterocyclic Schiff bases(Journal of the Chinese Chemical Society, 2020-08-04) Aral, Tarık; Dağ, Beşir; Kızılkaya, Hakan; Genç, Nusret; Erenler, RamazanSchiff base derivatives have gained great importance due to revealing a great number of biological properties. Schiff bases were synthesized by treatment of 4-amino-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one (1) with various aldehydes in methanol at reflux. In addition, diamine was reacted with an aldehyde to yield the corresponding Schiff bases. The structures of synthesized Schiff bases were elucidated by spectroscopic methods such as microanalysis, 1 H-NMR, 13C-NMR, and FTIR. Antioxidant activities of synthesized Schiff bases were carried out using different antioxidant assays such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH• ) scavenging, 2,20 -azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, and reducing power activity. (E)-4-((1H-indol-3-yl)methyleneamino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one (3), (E)-1,5-dimethyl-4-((2-methyl-1H-indol-3-yl) methyleneamino)-2-phenyl-1H-pyrazol-3(2H)-one (5), (E)-1,5-dimethyl-2-phenyl-4-(thiophen-2-ylmethyleneamino)-1H-pyrazol-3(2H)-one (7), (E)-1,5-dimethyl2-phenyl-4-(quinolin-2-ylmethyleneamino)-1H-pyrazol-3(2H)-one (9), (1S,2S, N1,N2)-N1,N2-bis((1H-indol-3-yl)methylene)cyclohexane-1,2-diamine (11), and (1S,2S,N1,N2)-N1,N2-bis((2-methyl-1H-indol-3-yl)methylene)cyclohexane-1,2-diamine (12) were synthesized in high yields. Compound 5 displayed a good ABTS•+ activity. Compound 3 revealed the outstanding activity in all assays. Compound 7 has the best-reducing power ability in comparison to other synthesized compounds. Although compounds 5, 11, 12 are new, compounds 3, 7, 9 are known. Due to revealing a good antioxidant activity, the synthesized compounds (3, 5, 7) have the potential to be used as synthetic antioxidant agents.Öğe Assessment of heavy metal pollution of urban soils of Batman by multiple pollution indices(Taylor & Francis, 2021-03-28) Baran, Hacı Alim; Gümüş Kıral, NurcanHeavy metal accumulation is observed in urban soils, sometimes due to anthropological effects and sometimes due to natural geological units. In order to determine the heavy metal content of the Upper MioceneLower Pliocene Selmo Formation, which is observed in the whole study area and consists of conglomerate, sandstone and silt stone, soil and river sediment samples were taken. Within the scope of pollution assessment, geo-accumulation index (Igeo), enrichment factor (EF) and pollution index (PI) calculations of Batman urban soil samples were made and different degrees of pollution values were determined. High pollution values were obtained for As, Mo and Sb elements in all pollution indices calculated. The pollution levels of the three elements were determined as strongly to extremely contaminated according to Igeo values, the others except As (very severe enrichment) according to EF values were determined as severe enrichment, and according to PI, all three were determined as strong polluted. Pollution and element distribution maps were created with a geographical information system software. According to the results of correlation analysis and cluster analysis, the elements found to be contaminated are divided into two groups, whose locations and sources of contamination are different. The first group (Sn, Zn and Pb) is observed in the approximate centre of the study area and developed due to traffic emissions. The elements belonging to the second group (especially As, Mo and Sb) show high pollution values in the south-southeast of the study area. These pollutions are thought to be caused by the inadequate storage of mineral oils and batteries that are changed in the industrial site and from leaks in the oil production, storage, refining and transmission phase in TPAO, TÜPRAŞ and BOTAŞ. The analysed samples were compared with the Soil Pollution Control Regulation and WHO standards, and Co, Ni and As element values were found to exceed the permissible values for healthÖğe Analysis of spheroidized AISI 1050 steel in terms of cutting forces and surface quality(Slovenska Akademia Vied, 2016) Baday, Şehmus; Başak, Hüdayim; Güral, AhmetIn this study, the effects of microstructure differences obtained with the application of different spheroidizing heat treatment cycles on medium carbon steel on cutting forces and surface roughness values were investigated. For this purpose, a group of AISI 1050 materials was annealed at 700°C below Ac1 temperature for 720 min and cementite phases were spheroidized by the traditional method. Another group of materials was quenched after austenitization at 850°C for 15 min and then cementites were spheroidized in the ferrite matrix by over-tempering separately at 600°C for 15 and 60 min and at 700°C for 60 min. Machining of the samples was tested under dry cutting conditions in CNC turning center with SNMG 120408 cementite carbide cutting tool and proper PSBNR 2525M12 tool holder with 75-degree edge angle. Cutting forces of traditionally spheroidized samples were lower than the samples spheroidized after quenching. In addition, their cutting forces decreased due to the increase in the average sizes of spheroidal cementite. Minimum surface roughness value was obtained from the samples which were spheroidized at 600°C for 15 min after quenching. However, surface roughness rate of the sample increased as spheroidizing time increased.Öğe “Balcı” aspir (Carthamus tinctorius l.) çeşidinin in vitro sürgün uçlarının mikroçoğaltımı ve köklendirilmesi üzerine oksin ve sitokininlerin etkisi(Yüzüncü Yıl Üniversitesi, 2018-12-31) Akbaş, Filiz; Hamidi Birecikli, AtikeBu çalışmada, linoleik tipte olan Balcı aspir çeşidinin, mikroçoğaltımı ve köklendirilmesi üzerine bazı sitokinin (BAP ve Kin) ve oksinlerin (NAA ve IAA) etkisi incelenerek in vitro çoğaltım protokolünün geliştirilmesi amaçlanmıştır. Başlangıç materyali olarak, in vitro koşullarda çimlendirilen olgun tohumlardan elde edilen steril fidelerin sürgün uçları kullanılmıştır. Sürgün uçları mikroçoğaltım için, BAP ve Kin’in farklı konsantrasyonlarının (0.0, 0.5, 1.0, 2.0 ve 4.0 mg/L) bulunduğu MS besi ortamında kültüre alınmıştır. Elde edilen sürgünler köklendirme aşamasında farklı NAA ve IAA (0.0, 0.5, 1.0 ve 2.0 mg/L) konsantrasyonlarını içeren MS besi ortamına transfer edilmiştir. BAP konsantrasyonları arasında en iyi sürgün çoğaltımı, eksplant başına 5.33 adet sürgün ile 0.5 mg/L BAP’lı ortamdan elde edilirken, Kin uygulamalarında ise 3.75 adet sürgün ile 0.5 mg/L Kin ve 3.33 adet sürgün ile 4.0 mg/L Kin içeren ortamdan elde edilmiştir. Ancak BAP uygulamalarının genelinde ve 4.0 mg/L Kin uygulamasında oluşan sürgünlerde vitrifikasyon olduğu belirlenmiştir. Bu nedenle, 0.5 mg/L Kin ile desteklenmiş MS besi ortamının Balcı aspir çeşidinin in vitro sürgün çoğaltımı için en ideal ortam olduğu tespit edilmiştir. En iyi kök oluşumunun, eksplant başına 20 adet ile 2.0 mg/L NAA içeren ortamda kültüre alınan sürgünlerde olduğu saptanmıştır. Elde edilen köklü fideler torf – perlit karışımı içeren saksılara dikilerek toprağa adaptasyonu sağlanmıştır.Öğe Exhaust emissions of methanol and ethanol-unleaded gasoline blends in a spark ignition engine(VINCA Institute of Nuclear Sciences, 2013) Altun, Şehmus; Öztop, Hakan Fehmi; Öner, Cengiz; Varol, YasinIn this study, the effect of unleaded gasoline and unleaded gasoline blended with 5% and 10% of ethanol or methanol on the performance and exhaust emissions of a spark-ignition engine were experimentally investigated. The engine tests were performed by varying the engine speed between 1000 and 4000 rpm with 500 rpm period at three-fourth throttle opening position. The results showed that brake specific fuel consumption increased while brake thermal efficiency, emissions of carbon monoxide and hydrocarbon decreased with methanol-unleaded gasoline and ethanol-unleaded gasoline blends. It was found that a 10% blend of ethanol or methanol with unleaded gasoline works well in the existing design of engine and parameters at which engines are operating.Öğe Voltammetric behavior of acebutolol on pencil graphite electrode: highly sensitive determination in real samples by square‑wave anodic stripping voltammetry(Iranian Chemical Society, 2017-08-22) Levent, AbdulkadirIn this work, an electrochemical investigation of acebutolol (ACE), a beta-blocker drug, was carried out in alkaline medium using pencil graphite (PG) electrode. In cyclic voltammetry, the compound displayed a reversible and adsorption-controlled oxidation peak. By using squarewave anodic stripping voltammetry, the oxidation peak current observed at +0.78 V showed a linear relationship with concentration at 0.4–7 nM interval in Britton–Robinson bufer (pH 10.0) and a detection limit of 0.09 nM. The relative standard deviation of 4.72% for the concentration level of 2.0 nM (n = 11) was also calculated. The PG electrode that is used for the frst time in this method was successfully applied to determine the ACE in pharmaceutical formulations and urine.
