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111.
In this paper we will prove the pointwise convergence of L(f; x, y, λ) to f(x0, y0), as (x, y, λ) tends to (x0, y0, λ0) in the space L2π, by the three parameter family of singular operators. In contrast to previous works, the kernel function is radial. 相似文献
112.
113.
114.
115.
116.
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
117.
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
118.
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
119.
İsmail Yener Mustafa Abdullah Yilmaz Özge Tokul Ölmez Pelin Köseoğlu Yılmaz Yeter Yeşil 《Analytical letters》2019,52(7):1031-1049
The Euphorbiaceae family comprises of about 300 genera and 5000 species primarily distributed in America and tropical Africa. The Euphorbia genus is represented by 105 species and locally named as “Sütle?en” and “Xa?îl” in Turkey. The present study aimed to determine the chemical constituents of E. aleppica, E. eriophora, E. macroclada, E. grisophylla, E. seguieriana subsp. seguieriana, E. craspedia, E. denticulata, E. falcata, and E. fistulosa, and classify them by utilizing the chemometric techniques of principal component analysis (PCA) and hierarchical cluster analysis (HCA). Linoleic acid, 17-tetratriacontane, palmitic acid, and hexatriacontane were the major fatty acids from the gas chromatography–mass spectrometry (GC/MS) analyses. Characterization of 268 constituents of the studied species was achieved by liquid chromatography–ion trap–time-of-flight–mass spectrometry (LC-IT-TOF-MS). Furthermore, a new liquid chromatography–tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous quantitative determination of 11 compounds (quinic acid, protocatechuic acid, rutin, hesperidin, eugenol, p-coumaric acid, piceatannol, scopoletin, dl-kavain, chrysophanic acid, and resiniferatoxin) in these species. The developed method was validated for the linearity, limit of detection, limit of quantification, repeatability, and recovery. 相似文献
120.
New palladium(II) and platinum(II) complexes, cis-[Pd(bpy)(sac)2] (1) and cis-[Pt(bpy)(sac)2] (2), where sac = saccharinate, bpy = 2,2′-bipyridine, have been synthesized and characterized by elemental analysis, UV–Vis, IR, 1H NMR and 13C NMR. The structures of the DMSO solvated complexes are determined by X-ray diffraction. Both complexes are isomorphous and the metal ions are coordinated by two N-bonded sac ligands, and two nitrogen atoms of pyridyl groups of bpy in a cis fashion. The mononuclear species interact each other through weak intermolecular C–H?O hydrogen bonds, C–H?π and π?π interactions leading to three-dimensional supramolecular networks. All complexes exhibit a high thermal stability in the solid state, and are fluorescent in the solution. 相似文献