68 research outputs found

    Determination of Optimum Compression Ratio: A Tribological Aspect

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    Internal combustion engines are the primary energy conversion machines both in industry and transportation. Modern technologies are being implemented to engines to fulfill today's low fuel consumption demand. Friction energy consumed by the rubbing parts of the engines are becoming an important parameter for higher fuel efficiency. Rate of friction loss is primarily affected by sliding speed and the load acting upon rubbing surfaces. Compression ratio is the main parameter that increases the peak cylinder pressure and hence normal load on components. Aim of this study is to investigate the effect of compression ratio on total friction loss of a diesel engine. A variable compression ratio diesel engine was operated at four different compression ratios which were "12.96", "15:59", "18:03", "20:17". Brake power and speed was kept constant at predefined value while measuring the in- cylinder pressure. Friction mean effective pressure ( FMEP ) data were obtained from the in cylinder pressure curves for each compression ratio. Ratio of friction power to indicated power of the engine was increased from 22.83% to 37.06% with varying compression ratio from 12.96 to 20:17. Considering the thermal efficiency , FMEP and maximum in- cylinder pressure optimum compression ratio interval of the test engine was determined as 18.8 ÷ 19.6

    Synthesis, in vitro antioxidant and antimicrobial activities of some novel 3-substitued-4-(3-methoxy-4-isobutyryloxybenzylideneamino)-4,5-dihydro- 1H-1,2,4-triazol-5-one derivatives

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    271-282In this study, 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones have been reacted with 3-methoxy-4-isobutyryloxybenzaldehyde 2 to afford the corresponding nine new 3-alkyl(aryl)-4-(3-methoxy-4-isobutyryloxybenzylideneamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones 3. Then, the acetylation reactions of compounds 3 have been investigated and 4 type compounds have been obtained. The compounds 3 have also been treated with morpholine/1-methylpiperazine in the presence of formaldehyde according to the Mannich reaction to synthesize 1-(morpholine-4-yl-methyl)-3-alkyl(aryl)-4-(3-methoxy-4-isobutyryloxy-benzylideneamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones 5, and 1-(1-methylpiperazin-4-yl-methyl)-3-alkyl(aryl)-4-(3-methoxy-4-isobutyryloxybenzylideneamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones 6, respectively. The structures of twenty four new compounds have been characterized by IR, 1H and 13C NMR and MS spectroscopic methods. In addition, the newly synthesized compounds have been screened for their antimicrobial activities. Furthermore, these twenty four new compounds have been analyzed for their in vitro potential antioxidant activities by three different methods

    Switchgrass as a potential forage grass for Gümüşhane region and its biomass production

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    Dallı darı (Panicum virgatum L.) yüksek ot verimi, iyi düzeydeki yem değeri, biyoenerji kaynağı teşkil etmesi, derin kök sistemi geliştirmesi, toprağı iyileştirmesi, kurağa dayanıklı olması ve nispeten fakir yetişme ortamlarında gelişebilmesi gibi özellikleri nedeni ile önemli bir yem bitkisi türüdür. Dallı darının kökleri uygun yetişme ortamlarında 3.3 m. derine kadar inebilmektedir. Yıllık toprak üstü net biyokütle üretimi hektarda 17 ile 35 ton arasında değişmektedir. Ancak bu değer uygun olmayan yetişme ortamlarında 8-10 ton/ha’a kadar düşebilmektedir. Yıllık net toprak altı biyokütle üretimi yaklaşık 8 ton/ha cıvarında olabilmekte, bu değer kurak ve fakir yetişme ortamlarında 15 ton/ha’a kadar çıkabilmektedir. Dallı darı, uygun varyete ve orijinleri denenerek, Gümüşhane ve yöresi hayvancılığı için çok faydalı olabilecek bir tür niteliğindedir.Switchgrass is one of the important grass species with its deep root system, high annual above- and belowground production, good quality forage, potential to use for bioenergy, resistance to drought, ability to grow in poor soils and potential to improve soil quality. Switchgrass develops roots that penetrates up to 330 cm soil depth. Annual net aboveground production ranges from 17 to 35 tons/ha. However this value can decrease to 8 to 10 tons/ha in poor soil conditions. Annual net belowground production is generally around 8 tons/ha, but it can go up to 15 tons/ha in dry and poor soil conditions. Switchgrass could provide lots of benefits to livestock production in Gümüşhane if right varieties and cultivars have chose

    Platinum nanoparticles involved on nitrogen and sulfur-doped nanomaterial as fuel cell electrode

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    A fuel cell is an electrochemical cell that converts a source fuel into an electrical current. It generates electricity inside a cell through reactions between a fuel and an oxidant, triggered in the presence of an electrolyte. Fuel cells have been attracting more and more attention in recent decades due to high-energy demands, fossil fuel depletions, and environmental pollution throughout world. In this study, a facile and cost-effective catalysts have been developed on platinum nanoparticles (PtNPs) supported on nitrogen and sulfur-doped nanomaterial (PtNPs-NS). The successful synthesis of nanomaterials and the prepared glassy carbon electrode (GCE) surfaces were confirmed by transmission electron microscope (TEM), X-ray photo electron spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. According to TEM images, the average particle sizes of PtNPs were found to be approximately 20–25 nm. The effective surface areas of NS/GCE and PtNPs-NS/GCE were calculated to be 105 and 518 cm2/mg, respectively. The PtNPs-NS/GCE also exhibited a higher peak current for methanol oxidation than those of comparable GCE and NS/GCE, providing evidence for its higher electro-catalytic activity. © 2016, Springer Science+Business Media New York

    Platinum nanoparticles supported on nitrogen and sulfur-doped reduced graphene oxide nanomaterial as highly active electrocatalysts for methanol oxidation

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    A fuel cell is an electrochemical cell that converts a source fuel into an electrical current. It generates electricity inside a cell through reactions between a fuel and an oxidant, triggered in the presence of an electrolyte. Fuel cells have been attracting more and more attention in recent decades due to high-energy demands, fossil fuel depletions and environmental pollution throughout world. In this study, a facile and cost-effective catalysts have been developed on platinum nanoparticles (PtNPs) supported on nitrogen and sulfur-doped reduced graphene oxide (NSrGO). The successful synthesis of nanomaterials and the prepared glassy carbon electrode (GCE) surfaces were confirmed by transmission electron microscope (TEM), X-ray photo electron spectroscopy (XPS), scanning electron microscope (SEM) and electrochemical impedance spectroscopy (EIS). According to TEM images, the average particle sizes of PtNPs were found to be approximately 15–20 nm. The effective surface areas (ESA) of NSrGO/GCE and PtNPs/NSrGO/GCE were calculated to be 148 and 469 cm2/mg, respectively. The PtNPs/NSrGO/GCE also exhibited a higher peak current for methanol oxidation than those of comparable GCE and NSrGO/GCE, providing evidence for its higher electro-catalytic activity. © 2016, Springer Science+Business Media New York

    <i>In vitro</i> biological activity of some new 1,2,4-triazole derivatives with their potentiometric titrations

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    567-577In this study, 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones 3 have been reacted with 4-methoxy-3-(p-toluenesulfonyloxy)-benzaldehyde 1 to afford the corresponding nine new 3-alkyl(aryl)-4-[4-methoxy-3-(p-toluenesulfonyloxy)-benzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones 4. Then, the acetylation reactions of compounds 4 have been investigated and 5 type compounds have been obtained. The structures of fifteen new compounds have been characterized by IR, 1H and 13C NMR, MS and UV-Vis spectral data. The synthesized compounds have been analyzed for their in vitro potential antioxidant activities by three different methods. Those antioxidant activities have been compared to standard antioxidants such as BHA, BHT and α-tocopherol. Compounds 4b, 4d and 5d show best activity for iron binding. In addition, the compounds 4 have been titrated potentiometrically with tetrabutylammonium hydroxide (TBAH) in four non-aqueous solvents. Furthermore, these fifteen new compounds have been screened for their antimicrobial activities

    Electrochemical detection of atrazine in wastewater samples by copper oxide (CuO) nanoparticles ionic liquid modified electrode

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    In the present report, a new voltammetric sensor based on copper oxide nanoparticles involved in 2-(3-acetoxy-4-methoxybenzylidenamino)-thiophenol (AMT) ionic liquid (CuO NPs/ILs) was developed for atrazine (ATR) analysis. Firstly, the CuO NPs/ILs modified surface was investigated by using transmission electron microscopy (TEM), X-ray diffraction (XRD), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and energy dispersive X-ray analysis (EDX). The linearity range and the detection limit (LOD) of the prepared sensor were calculated as 1.0 × 10− 11–2.0 × 10− 9 and 2.0 × 10− 12 M, respectively. Voltammetric sensor was also applied to wastewater samples with high recovery. © 2017 Elsevier B.V

    Cytomegalovirus hepatitis in 49 pediatric patients with normal immunity

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    Synthesis, potentiometric titrations and antioxidant activities of some 4-acylamino-4,5-dihydro-1H-1,2,4-triazol-5-one derivatives

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    Five novel 3-alkyl-4-cinnamoylamino-4,5-dihydro-1H-1,2,4-triazol-5-ones (2) were synthesized by the reactions of 3-alkyl-4-amino-4,5-dihydro-1H-1,2,4- triazol-5-ones (1) with cinnamoyl chloride and characterized by elemental analyses and IR, 1H NMR, 13C NMR and UV spectral data. The newly synthesized compounds 2 were titrated potentiometrically with tetrabutylammonium hydroxide in four non-aqueous solvents such as isopropyl alcohol, t-butyl alcohol, acetonitrile and N,N-dimethylformamide and the half-neutralization potential values and the corresponding pKa values were determined for all cases. In addition, these new compounds (except compound 2a) and five recently reported 3-alkyl-4-isobutyrylamino-4,5-dihydro- 1H-1,2,4-triazol-5-ones (3) were screened for their antioxidant activities
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