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12.
Zafer Odabaş İmran Koç Ahmet Altındal Ali Rıza Özkaya Bekir Salih Özer Bekaroğlu 《Synthetic Metals》2010,160(9-10):967-977
The new mono-nuclear FeII 2 and ball-type homo-dinuclear FeII–FeII 3 phthalocyanines have been synthesized from the corresponding 4,4′-(1a,8b-dihydronaphtho[b]naphthofuro[3,2-d]-furan-7,10-diyl)bis(oxy)diphthalonitrile 1 while ball-type hetero-dinuclear FeII–CoII phthalocyanine 4 was synthesized from 2. The compounds have been characterized by elemental analysis, UV–vis, IR and MALDI-TOF-mass spectroscopies. The redox behaviours of the complexes were identified by controlled-potential coulometry, cyclic voltammetry and differential pulse voltammetry measurements on Pt in dimethylsulfoxide containing tetrabutylammonium perchlorate. The assignments of the redox processes and the understanding of the interactions between the metal phthalocyanine units in 3 and 4 were achieved by the combined evaluation of the voltammetric and in situ spectroelectrochemical outcomes. Complex 3 showed ring-based mixed-valence behaviour as a result of the considerable interaction between the phthalocyanine rings. On the other hand, the interactions between the two metal phthalocyanine units of 4 were found to be much weaker than those in 3. The potential application of molecular organic semiconductors needs the control adjustment of conductivity. Ac and dc conductivity measurements were performed with the applied external electric filed. At high frequency, the conduction follows the universal power law and conduction mechanism can be explained by classical hopping barriers mechanism for the system. 相似文献
13.
N. M. Durakbasa ÖVE 《e & i Elektrotechnik und Informationstechnik》2000,117(4):269-272
The importance of computer aided measurement techniques as a means of controlling industrial manufacturing and testing technical products with high accuracy is increasing ever more with the general goal of improving the quality of all kinds of products. This development started about twenty years ago and is still improving. There is also rapid development in biomedical technique and this demands the application of modern computerized measurement techniques and measuring devices. Especially computer aided co-ordinate metrology can be applied as a very important and universal tool for solving complex measuring tasks for workpiece metrology, to evaluate the measuring results to give the basis for the improvement and optimization of future work in the biomedical technique. 相似文献
14.
A. Weinmann ÖVE 《e & i Elektrotechnik und Informationstechnik》2001,118(4):167-173
A trade-off between optimum allocation of the entire set of eigenvalues and the size of controller norm or a general actuator
effort is carried out for continuous-time and discrete-time systems. Controllers achieving appropriate results are termed
holistic. The design is based on the trace and determinant of the closed-loop state-space matrix. To solve the problem within
the scope of actuating effort, the norm of the state controller matrixor the actuator effort transfer matrix are taken into
consideration. The method is also extended for designing holistic observers. For preserving stability, a Lyapunov condition
is included.
An erratum to this article is available at . 相似文献
15.
Xabier Rodríguez-Martínez Paula Hartnagel Sergi Riera-Galindo Gulzada Beket Thomas Österberg Feng Gao Thomas Kirchartz Olle Inganäs 《Advanced functional materials》2023,33(27):2301192
Non-fullerene acceptors have recently revolutionized indoor organic photovoltaics (OPVs) with power conversion efficiencies exceeding 30% in laboratory scale. Nevertheless, transferring their superior performance to larger-scale prototyping, i.e., air-processing via roll-to-roll compatible techniques, still shows severe challenges. Herein, the industrial potential of the PM6:IO4Cl blend, which is one of the most successful indoor OPV photoactive layers (PALs), is thoroughly investigated. The corresponding thick and semitransparent laminated devices are fabricated entirely in air, by blade and slot-die coating. Their current–voltage (J–V) characteristics show anomalous features depending on the illumination side, with the cathode side generally outperforming the anode counterpart. Electrical and optical modeling reveal that a plausible cause of such a phenomenon is a dead layer that forms at the PAL/anode contact interface that does not contribute to the photocurrent. Said layer becomes undetectable when the PALs are made thin enough (<35 nm each) leading to symmetric J–V curves and improved light utilization efficiency. By screening the photovoltaic performance of multiple donor:acceptor blends, certain all-polymer and polymer:fullerene PALs are identified as adequately symmetric candidates for thick device up-scaling. Finally, ternary blends based on PM6:IO4Cl:fullerene may constitute a viable route to mitigate the electrical asymmetry detected on conventional binary blends. 相似文献
16.
Emrah Öncü Rasit Tutgun Emre Aktas 《International Journal of Satellite Communications and Networking》2023,41(6):589-598
Conventional solid-state power amplifier (SSPA) design approach isolates radio frequency (RF) design from communication theory. In this paper, a unified SSPA design approach is proposed, which optimizes SSPA parameters (bias voltage and input RF signal power) to minimize total DC power consumption while satisfying received SNR constraint specified by the link budget. The effect of SSPA nonlinearity is quantified by the error vector magnitude measured at its output and the corresponding received SNR degradation is analyzed. Using the quantitative metrics for received SNR, it is possible to evaluate highly nonlinear SSPA classes such as Class-B or deep-Class AB, which are normally not considered in conventional SSPA design approach to be used in satellite communication applications. 相似文献
17.
S. I. Rembeza N. N. Kosheleva E. S. Rembeza T. V. Svistova E. Yu. Plotnikova E. Suvaci E. Özel G. Tuncolu C. Açiksari 《Semiconductors》2014,48(8):1118-1122
The study is concerned with high-purity SnO2 and ZnO powders produced from salt solutions of corresponding metals by low-temperature hydrothermal synthesis. Fragments of SnO2 and ZnO ceramic targets formed as 1 × 8 cm bars are fabricated by dry pressing. The bars are used to form composite targets for ion-beam sputtering and the fabrication of compositionally different (SnO2) x (ZnO)1 ? x (x = 1–0.5) films appropriate for the production of gas sensors or transparent electronic devices. The optical and electrical parameters of the films with different compositions are studied. 相似文献
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Stephan Pachnicke Sinan Özdür Helmut Griesser Cornelius Fürst Peter M. Krummrich 《Optical Fiber Technology》2009,15(5-6):414-419
The sensitivity of optical orthogonal-frequency division multiplexing (OFDM) transmission to the finite resolutions of the digital-to-analog (DAC) and analog-to-digital converters (ADC) has been analyzed using numerical simulations. We show that for back-to-back configuration the requirements regarding the number of quantization bits for the DACs are similar to the ones of the ADCs. After transmission over metro and long-haul distances a higher resolution of the DAC/ADC is required compared to back-to-back configuration. We show that after transmission it is sufficient to enhance either the ADC resolution or the DAC resolution by 1 bit. 相似文献