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111.
Unsteady plunging (heaving) of a wing in the form of a flat plate can give rise to pronounced axial flow in the small-scale
leading-edge vortex, during its initial stage of formation. Opposing axial flows along the vortex interact at the plane of
symmetry giving rise to large-scale patterns of streamwise-oriented vorticity, which can dominate the tip vortices over part
of the oscillation cycle. 相似文献
112.
Veysel T. Yilmaz Ahmet Karadag Carsten Thne Regine Herbst‐Irmer 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):948-949
In the neutral title complex, trans‐bis(2,2′‐iminodiethanol‐N,O)bis(isothiocyanato)nickel(II), [Ni(NCS)2(C4H11NO2)2], the isothiocyanate ions and the diethanolamine molecules act as monodentate and bidentate ligands, respectively. The NiII ion exhibits a distorted octahedral configuration with crystallographically imposed inversion symmetry and NNCS—Ni—Namine and NNCS—Ni—Oamine bond angles of 88.78 (10) and 89.44 (10)°, respectively. The Ni—N bond distances are in the range 2.069 (3)–2.096 (2) Å. The molecules are linked by hydrogen bonds to form a three‐dimensional infinite lattice. 相似文献
113.
A.A. Esaulov V.L. Kantsyrev A.S. Safronova K.M. Williamson I. Shrestha G.C. Osborne M.F. Yilmaz N.D. Ouart M.E. Weller 《High Energy Density Physics》2009,5(3):166-172
The radiative performance of Z-pinches created by the imploding wire array loads is defined by the ablation and implosion dynamics of these loads. Both these processes can be effectively modeled by the Wire Ablation Dynamics Model (WADM), which extends the formalism exploited earlier for the cylindrical wire arrays to the loads of arbitrary geometries. The WADM calculates the ablation rates for each array wire and provides the important dynamic parameters, such as the specific mass and velocity of the imploding plasma, which can be used to estimate the shapes of the x-ray pre-pulse and, partially, the main x-ray burst. The applications of the WADM also extend to combined material wire array loads. The ablation and implosion dynamics of novel Prism Planar Wire Array (PPWA) and combined material (Mo/Al/Mo) Triple Planar Wire Array (TPWA) loads are discussed in detail. The combined WADM and radiation MHD simulation is applied to model the radiative performance of the precursor plasma column, created by the imploding stainless steel compact cylindrical wire array. As the radiation effects intensify with the mass accumulation at the array center, the simulation reveals the transformation of quasi-uniform precursor column into a heterogeneous plasma structure with strong density and temperature gradients. We find that radiative performance of the precursor plasma is greatly affected by the load geometry as well as by the wire material. 相似文献
114.
Azra Kocaarslan Gorkem Yilmaz Clemens Liedel Yusuf Yagci 《Journal of polymer science. Part A, Polymer chemistry》2020,58(1):62-69
A novel synthetic strategy for the synthesis of graft copolymers is reported. Block copolymers containing segments with stable nitroxyl radicals side groups were first prepared by anionic polymerization, which were then used as a precursor for the subsequent nitroxide-mediated radical polymerization (NMRP) of styrene. This way, block–graft copolymers with polystyrene side chains grafted from one of the blocks were successfully synthesized in a controlled manner. In addition, block–graft copolymers with grafted polystyrene chains and a poly(tert-butyl methacrylate) block were subjected to hydrolysis to yield the corresponding amphiphilic polymers. The structures and the molecular weight characteristics of the polymers were characterized by spectral and chromatographic analyses. The surface morphology of thus obtained polymers was also investigated by microscopic techniques. © 2019 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 62–69 相似文献
115.
116.
117.
Yilmaz Simsek 《Journal of Mathematical Analysis and Applications》2006,318(1):333-351
The main purpose of this paper is to define new generating functions. By applying the Mellin transformation formula to these generating functions, we define q-analogue of Riemann zeta function, q-analogue Hurwitz zeta function, q-analogue Dirichlet L-function and two-variable q-L-function. In particular, by using these generating functions, we will construct new generating functions which produce q-Dedekind type sums and q-Dedekind type sums attached to Dirichlet character. We also give the relations between these sums and Dedekind sums. Furthermore, by using *-product which is given in this paper, we will give the relation between Dedekind sums and q-L function as well. 相似文献
118.
Osman Yilmaz Ali Usanmaz Kemal Alyürük 《Journal of polymer science. Part A, Polymer chemistry》1993,31(13):3205-3211
n-Butyl isocyanate (nBIC) was polymerized in bulk by the Pruitt–Baggett adduct (PBA) at ?23, 0.0, and 25.0°C. Polymerization was accompanied by trimerization to the cyclicisocyanurates at all temperatures. Spectroscopic evidences supported the nylon-1 structure for both trimer and polymer. The polymer/trimer ratio and the molecular weight of produced polymers were found to increase with decreasing temperature. The Pruitt–Baggett catalyst (PBC), which is the reaction product of (PBA + H2O) system, also polymerized nBIC, but with a relatively slower rate. In aromatic and etheric solutions, nBIC was only trimerized by PBA. Copolymerization of nBIC with propylene oxide by PBA and PBC failed. Some selected monoisocyanates were also polymerized by PBA. © 1993 John Wiley & Sons, Inc. 相似文献
119.
Ammonium salts of p-methoxyphenyldithiophosphonic acid O-alkyl esters (H3CO-C6H4-(RO)P(S)S−NH
4
+
; R = C2H5,-CH2CH2CH2CH2-, and cyclopentyl) and their complexes with Ni2+, Cd2+, and Zn2+ were prepared. 2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide, the so-called Lawesson reagent, was treated
with the corresponding alcohol to give the O-alkyl ester of the acid. Dry NH3 was then purged through the solution of this ester to form the ammonium salt of the O-alkyl dithiophosphonic acids. Nickel
complexes of these ligands were formed in acetic acid, while zinc and cadmium complexes were formed in water and an ethanol
medium, respectively. The geometry of the coordinated atoms was square planar with Ni2+ and tetrahedral with Zn2+ and Cd2+. Using an alkanediol, two dithiophosphonic acids were bridged, thus forming a ligand with four S atoms for coordination.
The zinc and cadmium complexes of these tetradentate ligands were also synthesized.
The text was submitted by the authors in English. 相似文献
120.
Erkan Yilmaz Yıldız Tut Orhan Turkoglu Mustafa Soylak 《Journal of the Iranian Chemical Society》2018,15(8):1721-1731
In this study, Pd nanoparticle-modified magnetic Sm2O3–ZrO2 material (Pd–Fe3O4–Sm2O3–ZrO2) as multifunctional catalyst was fabricated and used for catalytic reduction of 2-nitrophenol compound, degradation of methylene blue and rhodamine B dyes, which are toxic pollutants. The magnetic material was used for the first time as a catalyst for the reduction and degradation studies. Pd nanoparticle-modified magnetic Sm2O3–ZrO2 catalyst was prepared using the deposition–precipitation methods and were characterized by X-ray diffraction, scanning electron microscopy, atomic absorption spectrometry, Raman spectroscopy and BET surface analyzer. The Pd nanoparticle-modified magnetic Sm2O3–ZrO2 material can lead to high catalytic activity for the reduction of 2-nitrophenol and degradation of rhodamine B and methylene blue with >?95% conversion within ~?2 and 80 s even when the content of Pd in it is as low as 5.8 wt%. 相似文献