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161.
O. Karabulut M. Parlak R. Turan U. Serincan B. G. Aknolu 《Crystal Research and Technology》2006,41(3):243-249
The structure and temperature dependent spectral photoconductivity of as‐grown and N‐and Si‐implanted GaSe single crystals have been studied. It was observed that post‐annealing results in a complete recovery of the crystalline nature that was moderately reduced upon implantation. The band edge is shifted in the implanted sample which is attributed to the structural modifications and continuous shallow levels introduced upon implantation and annealing. Our calculations showed that the trap density is increased upon implantation and annealing which confirms a possibility of explanation the phenomenon within a framework of continuous trap levels. Photocurrent measurements as a function of photo‐excitation intensity also support continuous distribution of localized states in the band gap. © 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim 相似文献
162.
C. Turan P. M. Carrica L. Weber 《International Journal of Computational Fluid Dynamics》2013,27(3-4):137-153
Strong flow entrainment has been observed downstream of spillways constructed with flow deflectors. This water entrainment has important environmental and ecological impacts because it improves the mixing of powerhouse and spillway flows, but may negatively impact fish migration or create adverse flow conditions. Most studies found in the literature attempt to explain this entrainment with turbulent mixing. Both reduced-scale hydraulic models and single-phase, isotropic RANS models grossly under-predict the degree of entrainment observed in prototypes. In this paper, an anisotropic model that accounts for the bubble volume fraction and attenuation of the normal velocity fluctuations at the free surface is presented. The model adequately predicts the main mechanisms causing water entrainment and compares well against experimental data for a round surface jet and for Brownlee Dam at model scale. It is shown that appropriate entrainment can only be captured if the turbulence anisotropy and the two-phase nature of the flow are modelled. 相似文献
163.
Emin Turan Onat Walter Schumann Rich Thorpe Shield 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1957,8(6):485-499
Zusammenfassung Diese Arbeit befasst sich mit dem Problem der Bemessung einer elastischplastischen Kreisplatte veränderlicher Dicke von minimalem Gewicht. Die Platte ist am Rand frei drebhar gelagert oder eingespannt und trägt eine rotationssymmetrische, sonst beliebig verteilte Last. Es wird das vonDrucker undShield entwickelte Verfahren zur Dimensionierung verwendet, welches ein absolutes Minimum für das Gewicht einer Sandwichplatte und ein relatives Minimum für dasjenige einer homogenen Platte liefert.
The results presented in this paper were obtained in the course of research work sponsored by Watertown Arsenal Laboratory under Contract DA-19-020-ORD-2598-DA-19-020-501-ORD-3984. 相似文献
The results presented in this paper were obtained in the course of research work sponsored by Watertown Arsenal Laboratory under Contract DA-19-020-ORD-2598-DA-19-020-501-ORD-3984. 相似文献
164.
In this paper we investigate differential equations on certain time scales with transition conditions (DETC) on the basis of reduction to the impulsive differential equations (IDE). DETC are in some sense more general than dynamic equations on time scales [M. Bohner, A. Peterson, Dynamic equations on time scales, in: An Introduction With Applications, Birkhäuser Boston, Inc., Boston, MA, 2001, p. x+358; V. Laksmikantham, S. Sivasundaram, B. Kaymakcalan, Dynamical Systems on Measure Chains, in: Math. and its Appl., vol. 370, Kluwer Academic, Dordrecht, 1996]. The basic properties of linear systems, the existence and stability of periodic solutions, and almost periodic solutions are considered. Appropriate examples are given to illustrate the theory. 相似文献
165.
Buldurun Kenan Turan Nevin Bursal Ercan Mantarcı Asim Turkan Fikret Taslimi Parham Gülçin İlhami 《Research on Chemical Intermediates》2020,46(1):283-297
Research on Chemical Intermediates - Considering the importance of metal complexes in the development of medical science, two different Schiff base Fe(II) and Co(II) metal complex compounds were... 相似文献
166.
Nilgün?Kabay Emin?ErdemEmail author Rafet?K?l?n?arslan Eylem?Y?ld?r?m?Sar? 《Transition Metal Chemistry》2007,32(8):1068-1072
The synthesis and characterization of azo dyes containing o,o′-dihydroxy groups and their azo-metal(II) [Cu, Co, Ni, Zn] chelates by 1H N.M.R., IR, AAS, UV–VIS, magnetic susceptibility and thin-layer chromatography techniques are reported. The stochiometry
of the azo-metal chelates was determined by the spectroscopic titration method to be 1:2 (ML2). The synthesized azo dyes and azo-metal chelate dyes were applied on wool fabric. Fastness to light and washing were measured. 相似文献
167.
A method for analysis of the global stability of dynamic systems with pulse-width modulation that are presented in the form
of Poincaré mappings is suggested. The method has enhanced efficiency from the viewpoint of the required computing time. Results
of this work can be used for automatic analysis and design of these systems. 相似文献
168.
Tugberk Tabak Kerem Kaya Recep Isci Turan Ozturk Yusuf Yagci Baris Kiskan 《Macromolecular rapid communications》2024,45(2):2300455
A novel method based on light-induced fabrication of a poly (3,4-ethylenedioxythiophene)-polycaprolactone (PEDOT-PCL) scaffold using phenacyl bromide (PAB) as a single-component photoinitiator is presented. HBr released from the step-growth polymerization of EDOT is utilized as an in situ catalyst for the chain-growth polymerization of ε-caprolactone. Detailed investigations disclose the formation of a self-assembled nanoporous electroconductive scaffold (1.2 mS cm−1). Fluorescence emission spectra of the fabricated scaffold exhibit a mixed solvatochromic behavior, indicating specific interactions between the self-assembled scaffold and solvents with varying polarities, as evidenced by transmission electron microscopy (TEM). Moreover, the same light-induced technique can also be applied for bulk photopolymerization showcasing the versatility and wide-ranging scope of the originated method. In brief, this study introduces a novel approach for light-induced polymerization reactions that is merging step-growth and chain-growth mechanisms. This innovative approach is promising to facilitate in situ polymerization of monomers possessing diverse functionalities. 相似文献