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71.
A new high‐performance blue to transmissive electrochromic material and use of silver nanowire network electrodes as substrates
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Janset Turan Ece Alpugan Serife Ozdemir Hacioglu Levent Toppare Ali Cirpan Husnu Emrah Unalan Gorkem Gunbas 《Journal of polymer science. Part A, Polymer chemistry》2017,55(10):1680-1686
Synthesis of a novel, high‐performance blue to transmissive switching electrochromic material is described. The polymer (P1) was prepared by both electrochemical ( P1E ) and chemical ( P1C ) means from the corresponding monomer. The electrochemically synthesized polymer ( P1E ) revealed 64% optical contrast change (on ITO) in the visible region and very fast switching times of 0.32 s (coloration) and 0.90 s (bleaching). On the other hand, the chemically synthesized, solution processable polymer ( P1C ) also showed a high optical contrast value (49%, on ITO) with very fast switching times of 0.86 s for coloration and 0.57 s for bleaching. These high optical contrast values coupled with fast switching times place these materials along with high‐performance blue to transmissive electrochromic polymers. Significantly, these improved characteristics were achieved by side chain engineering of a known, inferior blue to transmissive polymer, PBEBT. Towards fabrication of flexible electrochromic devices, the performance of P1C was also tested on silver nanowire network electrodes. Even though the full potential of the material could not be demonstrated, a good optical contrast of 24% was achieved using these electrodes. Under the same potential range allowed by silver nanowire network electrodes, P1C on ITO showed an optical contrast of 30%. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 1680–1686 相似文献
72.
In this work, photovoltaic performance of Ga-doped ZnO thin film/Si NWs heterojunction diodes was investigated. Highly dense and vertically well-aligned Si NW arrays were successfully synthesised on a p-type (1?0?0)-oriented Si wafer through cost-effective metal-assisted chemical etching technique. Ga-doped ZnO thin films were deposited onto Si NWs via radio frequency magnetron sputtering to construct three-dimensional heterostructures. Photovoltaic characteristics of the fabricated diodes were determined with current density (J)–voltage (V) measurements under simulated solar irradiation of AM 1.5 G. The optimal open-circuit voltage, short-circuit current density, fill factor and power conversion efficiency were found to be 0.37 V, 3.30 mA cm?2, 39.00 and 0.62%, respectively. Moreover, photovoltaic diodes exhibited relatively high external quantum efficiency over the broadband wavelengths between 350 and 1100 nm interval of the spectrum. The observed photovoltaic performance in this study clearly indicates that the investigated device structure composed of Ga-doped ZnO thin film/Si NWs heterojunctions could facilitate an alternative pathway for optoelectronic applications in future, and be a promising alternative candidate for high-performance low-cost new-generation photovoltaic diodes. 相似文献
73.
Emrah Polatlı 《Advances in Applied Clifford Algebras》2016,26(2):719-730
In this paper, we give a generalization of the Fibonacci and Lucas quaternions. We obtain the Binet formulas, generating functions, and some certain identities for these quaternions which include generalizations of some results of Halici. 相似文献
74.
Emrah Torlak 《Accreditation and quality assurance》2012,17(6):597-601
Calculation of measurement uncertainty is a requirement for all laboratories accredited to ISO/IEC 17025 including those carrying out microbiological analyses. Today, calculation of measurement uncertainty in microbiological analyses using precision data according to global approach principles is widely recognized by the microbiologists due to difficulties in quantification of individual uncertainty sources. In food microbiology, precision data obtained from different samples usually show over-dispersion, and the use of over-dispersed data may result in large variance. The current ISO standard on measurement uncertainty in food microbiology proposes the use of log-transformed precision data to overcome this problem. This paper proposes an alternative procedure to calculate the measurement uncertainty in food microbiology using non-logarithmic precision data. The calculations used in this procedure based on relative range of duplicate analyses can be applied to intra-laboratory reproducibility data obtained from microbiological analyses of which duplicate results show relatively low variation. 相似文献
75.
We hereby report the first preparation of the 5,6‐dihydro‐4H‐furo[2,3‐c]pyrrol‐4‐one ( 3 ) and its derivatives starting from methyl 3‐(methoxycarbonyl)furan‐2‐acetate ( 8 ). The ester functionality connected to the methylene group was regiospecifically converted to the desired monohydrazide 9 . Conversion of 9 into the acyl azide 10 followed by Curtius rearrangement gave the corresponding isocyanate derivative 11 (Scheme 2). Reaction of 11 with different nucleophiles produced urethane and urea derivatives (Scheme 3). Intramolecular cyclization reactions provided the target compounds (Scheme 5). Removal of the amine‐protecting group formed the title compound 3 . 相似文献
76.
Sevdiye Atakul Savrık Devrim Balköse Sevgi Ulutan Semra Ülkü 《Journal of Thermal Analysis and Calorimetry》2010,101(2):801-806
The effect of emulsion process formulation ingredients on the morphology, structure, and properties of polyvinyl chloride
(PVC) powder has been considered in this study. PVC powder was extracted with ethanol and films were obtained by solvent casting
from tetrahydrofurane. Characterization of powders, films, and ethanol extract was performed through FTIR spectroscopy, DSC,
AFM, SEM, EDX analysis, methylene blue, and nitrogen adsorption. PVC powder was composed of spheres of a large particle size
range from 10 nm to 20 μm as shown by SEM. The specific surface area of the PVC powder was determined as 16 and 12 m2 g−1 from methylene blue adsorption at 25 °C and from N2 adsorption at −196 °C, respectively. AFM indicated the surface roughness of the films obtained by pressing the particles
was 25.9 nm. Density of PVC powder was determined by helium pycnometry as 1.39 g cm−3. FTIR spectroscopy indicated that it contained carbonyl and carboxylate groups belonging to additives such as surface active
agents, plasticizers, and antioxidants used in production of PVC. These additives were 1.6% in mass of PVC as determined by
ethanol extraction. EDX analysis showed PVC particles surfaces were coated with carbon-rich materials. The coatings had plasticizer
effect since, glass transition temperature was lower than 25 °C for PVC powder and it was 80 °C for ethanol extracted powders
as found by using differential scanning calorimetry. These additives from polymerization process made PVC powder more thermally
stable as understood from Metrom PVC thermomat tests as well. 相似文献
77.
78.
Ahmet Örnek Emrah Bulut Mustafa Can Mahmut Özacar 《Journal of Solid State Electrochemistry》2013,17(12):3101-3107
Pure LiFePO4 and LiNi x Fe1?x PO4/C (x?=?0.00–0.20) nanocomposite cathode materials have been synthesized by cheap and convenient sol–gel-assisted carbothermal reduction method. X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy, and inductively coupled plasma have been used to study the phase, morphology, and chemical composition of un-doped and Ni-doped materials. XRD patterns display the slight shrinkage in crystal lattice of LiFePO4 after Ni2+ doping. The SEM images have revealed that Ni-doped particles are not agglomerated and the particle sizes are practically homogeneously distributed. The particle size is found between 50 and 100 nm for LiNi0.20Fe0.80PO4/C sample. The discharge capacity at 0.2 C rate has increased up to 155 mAh g?1 for the LiNi0.05Fe0.95PO4/C sample and good capacity retention of 99.1 % over 100 cycles, while that of the unsubstituted LiFePO4/C and pure LiFePO4 has showed only 122 and 89 mAh g?1, respectively. Doping with Ni has a noticeable effect on improving its electrical conductivity. However, serious electrochemical declension will occur when its doping density is beyond 0.05 mol LiNi0.20Fe0.80PO4/C electrode shows only 118 mAh g?1, which is less than un-doped LiFePO4/C sample at 0.2 C. The cycling voltammogram demonstrates that Ni-doped LiNi0.05Fe0.95PO4/C electrode has more stable lattice structure, enhanced conductivity, and diffusion coefficient of Li+ ions, in which Ni2+ is regarded to act as a column in crystal lattice structure to prevent the collapse during cycling process. 相似文献
79.
Nevroz Aslan Ertas Emrah Kavak Frat Salman Hilal Celik Kazici Hilal Kivrak Arif Kivrak 《Electroanalysis》2020,32(6):1178-1185
At present, a highly sensitive hydrogen peroxide (H2O2) sensor is fabricated by ferrocene based naphthaquinone derivatives as 2,3‐Diferrocenyl‐1,4‐naphthoquinone and 2‐bromo‐3‐ferrocenyl‐1,4‐naphthoquinone. These ferrocene based naphthaquinone derivatives are characterized by H‐NMR and C‐NMR. The electrochemical properties of these ferrocene based naphthaquinone are investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) on modified glassy carbon electrode (GCE). The modified electrode with ferrocene based naphthaquinone derivatives exhibits an improved voltammetric response to the H2O2 redox reaction. 2‐bromo‐3‐ferrocenyl‐1,4‐naphthoquinone show excellent non‐enzymatic sensing ability towards H2O2 response with a detection limitation of 2.7 μmol/L a wide detection range from 10 μM to 400 μM in H2O2 detection. The sensor also exhibits short response time (1 s) and good sensitivity of 71.4 μA mM?1 cm?2 and stability. Furthermore, the DPV method exhibited very high sensitivity (18999 μA mM?1 cm?2) and low detection limit (0.66 μM) compared to the CA method. Ferrocene based naphthaquinone derivative based sensors have a lower cost and high stability. Thus, this novel non‐enzyme sensor has potential application in H2O2 detection. 相似文献
80.
Frequency Selective Characteristics of a Plasma Layer with Sinusoidally Varying Electron Density Profile 总被引:1,自引:0,他引:1
Çiğdem Seçkin Gürel Emrah Öncü 《Journal of Infrared, Millimeter and Terahertz Waves》2009,30(6):589-597
In this study reflection, absorbtion and transmission characteristics of a plasma layer having sinusoidally varying electron
number density are analysed. In the analysis, plasma layer is divided into thin subslabs with constant electron number densities.
The general frequency selective behavior of the plasma is investigated by varying the plasma parameters, external magnetic
field excitation and sinusoidal electron distribution in order to be used in recent plasma applications. 相似文献