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21.
F. Banishoeib S. Fourier M. Breselge T.J. Cleij D. Vanderzande Le Huong Nguyen Niyazi Serdar Sariciftci 《Thin solid films》2008,516(12):3978-3988
Poly-(2,5-Thienylene Vinylene) (PTV) derivatives have been synthesised via the “dithiocarbamate precursor route” in good yield and satisfactory molecular weight. Structural characterisations of the conjugated PTV polymers reveal an optical band gap around 1.8 eV. Organic field effect transistors and organic based photovoltaic devices were made with the plain PTV, via a precursor approach. More specifically, solar cells were produced using a blend of the precursor PTV polymer and PCBM (1-(3-methoxycarbonyl) propyl-1-phenyl [6,6] C61) at various ratios, converted in situ in thin film. A promising power efficiency of 0.76% was achieved. 相似文献
22.
微生物侵蚀会导致混凝土的严重破坏,尤其导致了城市污水收集和处理系统的过早破坏,使其需要提前修复。世界范围内的研究结果表明:处于污水和下水道污泥中的混凝土会遭受由硫酸盐、酸、CO2等导致的严重破坏。评述了混凝土处于利于细菌生长和生物降解环境中时的细菌、微生物侵蚀破坏过程。此外还分析了硫酸产生的机理(硫循环)、用于污水管道系统和农用工业的混凝土的受侵蚀破坏机理以及评价混凝土抵抗微生物侵蚀的方法。 相似文献
23.
The electroanalytic performances of glassy carbon paste electrode (GCPE), multi-walled carbon nanotube (MWCNT)-GCPE and double-walled carbon nanotube (DWCNT)-GCPE, which include HNO3 washed/unwashed materials, were compared by monitoring cyclic voltammograms of potassium ferricyanide and catechol. Electrodes were prepared by introducing proper amount of DWCNT and MWCNT into GCPE. First untreated materials (DWCNT, MWCNT, GC μ-particles) were used in the electrodes and then HNO3-treated materials were utilized for comparing difference in electrochemical performances. The effect of treatment procedure was also examined by applying Raman spectroscopy to treated and untreated materials. Moreover, TEM images were obtained for further investigation of MWCNT and DWCNT. 相似文献
24.
Steel dome structures, with their striking structural forms, take a place among the impressive and aesthetic load bearing systems featuring large internal spaces without internal columns. In this paper, the seismic design optimization of spatial steel dome structures is achieved through three recent metaheuristic algorithms that are water strider (WS), grey wolf (GW), and brain storm optimization (BSO). The structural elements of the domes are treated as design variables collected in member groups. The structural stress and stability limitations are enforced by ASD-AISC provisions. Also, the displacement restrictions are considered in design procedure. The metaheuristic algorithms are encoded in MATLAB interacting with SAP2000 for gathering structural reactions through open application programming interface (OAPI). The optimum spatial steel dome designs achieved by proposed WS, GW, and BSO algorithms are compared with respect to solution accuracy, convergence rates, and reliability, utilizing three real-size design examples for considering both the previously reported optimum design results obtained by classical metaheuristic algorithms and a gradient descent-based hyperband optimization (HBO) algorithm. 相似文献
25.
Ozer Caglar Ebeoglugil M. Faruk Yildirim Serdar Nil Metin 《Journal of Materials Science: Materials in Electronics》2022,33(3):1511-1528
Journal of Materials Science: Materials in Electronics - In this study, ITO-coated PET was used as the substrate to create a flexible and transparent structure. a-IGZO (amorphous InGaZnO4) is... 相似文献
26.
As demand for more power increases, compression ratios, and operating temperatures keep rising. High speeds combined with high temperatures make turbomachinery sealing applications even more challenging. In order to confirm sufficient service life material pairs should be tested under conditions similar to engine operating conditions. This study presents high temperature friction and wear characteristics of cobalt/nickel superalloys, Haynes 25 (51Co–10Ni–20Cr–15W), Haynes 188 (39Co–22Ni–22Cr–14W), and Haynes 214 (75Ni–16Cr–3Fe–0.5Mn) sheets when rubbed against Hastelloy X (47Ni–22Cr–18Fe–9Mo) pins. Tests are conducted at 25, 200, 400, and 540 °C with a validated custom design linear reciprocating tribometer. Sliding speed and sliding distance are 1 Hz and 1.2 km, respectively. Friction coefficients are calculated with friction force data acquired from a load cell. Wear coefficients are calculated through weight loss measurements. Results indicate that Haynes 25 (H25) has the lowest friction coefficients at all test temperatures. Above 400 °C, H25 and Haynes 188 (H188) exhibit the best wear resistance. Protective cobalt oxide layers are formed on the H25 and H188 at 540 °C in addition to nickel, chrome, and tungsten oxides. Although, it has better oxidation resistance, Haynes 214 has relatively higher wear rates than other tested materials especially at low temperatures. However, its wear performance improves beyond 200 °C. 相似文献
27.
Durmuş Burhanettin Temurtaş Hasan Özyön Serdar 《Neural computing & applications》2020,32(22):17097-17113
Neural Computing and Applications - This study presents the design of a tenth-order multiple feedback Chebyshev low-pass filter (MF-C-LPF). Component selection and gain calculation of filters are... 相似文献
28.
Arne Palmaerts Thomas J. Cleij Dirk Vanderzande Almantas Pivrikas Niyazi Serdar Sariciftci 《Polymer》2009,50(21):5007-6388
Considerable interest exists in the development of novel n-type conjugated polymers, since many currently available polymer systems have insufficient electron mobility and/or electron affinity. In this work, a universal synthesis route is presented towards a new class of n-type conjugated polymers, i.e. poly(p-fluoranthene vinylene) (PFV) and its derivatives. This route is illustrated with three examples, i.e. unsubstituted PFV and functionalized hexyl-PFV and dodecyl-PFV. All polymers have been synthesized via the dithiocarbamate precursor route. Solubility was introduced by incorporation of alkyl side chains, which leads to a significantly enhanced purity and processability as compared to unsubstituted PFV. Under the applied electrochemical conditions PFV-type polymers demonstrate typical n-type behavior. Additional CELIV mobility measurements on dodecyl-PFV reveal an excellent electron mobility, μe = 1.4 × 10−4 cm2/Vs. Hence, poly(p-fluoranthene vinylene) and its derivatives are promising n-type materials for organic optoelectronic applications. 相似文献
29.
Halit Yazıcı Mert Yücel Yardımcı Serdar Aydın Anıl Ş. Karabulut 《Construction and Building Materials》2009,23(3):1223-1231
Mechanical properties (compressive strength, flexural strength, and toughness) of reactive powder concrete (RPC) produced with class-C fly ash (FA) and ground granulated blast furnace slag (GGBFS) were investigated under different curing conditions (standard, autoclave and steam curing) in this study. Test results indicate that, compressive strength of RPC increased considerably after steam and autoclaving compared to the standard curing. On the other hand, it was observed that steam and autoclave curing decreased the flexural strength and toughness. Increasing the GGBFS and/or FA content improved the toughness of RPC under all curing regimes considerably. Furthermore, SEM micrographs revealed dense microstructure of RPC. 相似文献
30.