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21.
Serap Bulut 《Applied mathematics and computation》2009,215(4):1448-1455
In this paper, firstly we define the generalization of the generalized Al-Oboudi differential operator. Then we also define new classes of analytic and p-valently starlike and convex functions with complex order by means of this new general differential operator. Our main purpose is to determine coefficient bounds for functions in certain subclasses of this classes, which are introduced here by means of a family of nonhomogeneous Cauchy-Euler differential equations. Relevant connections of some of the results obtained with those in earlier works are also provided. 相似文献
22.
Serap Seyhan Bozkurt Deniz Erdogan Mine Antep Nalan Tuzmen Melek Merdivan 《液相色谱法及相关技术杂志》2016,39(1):21-29
The possibility of using ionic liquid based chitosan sorbent for the separation and preconcentration of fluoroquinolone antibiotics (marbofloxacin, enoxacin, ofloxacin, ciprofloxacin, and enrofloxacin) has been studied. For this reason, different ionic liquids were prepared and coated on the chitosan sorbent. The conditions of the preconcentration of fluoroquinolones on a microcolumn have been optimized and the extraction efficiencies of the prepared sorbents have been compared. The compounds were eluted with 5 mL of 20% NH3 (v/v, MeOH) solution and determined by HPLC with diode array and fluorescence detector. The limits of detection were found as 4.23 µ g L?1 for marbofloxacin, and 1.09 µg L?1 for enoxacin; 3.23 × 10?3 µg L?1 for ofloxacin; 8.39 × 10?3 µg L?1 for ciprofloxacin; and 19.50 × 10?3 µg L?1 for enrofloxacin. The developed method was applied for the analysis of fluoroquinolone in milk, egg, fish, bovine, and chicken samples and the recoveries were obtained in the range 70–100%. 相似文献
23.
Deprotonation of a cyclotriphosphazene with a tert-butylamino group in the side chain results in ring expansion to a very stable, planar cyclohexaphosphazene derivative that still contains eight P-Cl bonds suitable for forming macromolecular structures. 相似文献
24.
Gülay Bayramoğlu Nilhan Kayaman‐Apohan Memet Vezir Kahraman Sabriye Karadenizli Serap Erdem Kuruca Atilla Güngör 《先进技术聚合物》2012,23(10):1403-1413
A branched methacrylated poly(caprolactone‐co‐lactic acid) and methacrylated poly(tetramethylene ether glycol) (PTMG‐IEM) resins were synthesized. 1H‐NMR spectroscopy, attenuated total reflectance Fourier transform infrared spectroscopy (ATR‐FTIR) spectroscopy, and gel permeation chromatography confirmed the chemical structures of copolymers. The photoinitiated polymerization of formulation composed of various amounts of methacrylated poly(caprolactone‐co‐lactic acid), PTMG‐IEM, poly(ethylene glycol) diacrylate, water, and photoinitiator were performed. The curing reactions were followed by photo‐DSC (Differential scanning calorimetry). Gel fraction was calculated from the insoluble part and found as ≥93%. Swelling and contact angles were measured, and all increased with the increasing amount of PTMG‐IEM in network formulations. In vitro degradation studies were performed at 37 °C in phosphate‐buffered saline (pH 7.4). Collagen‐modified polymers were also prepared and introduced as a bioactive moiety to modify the polymer to enhance cell affinity. To compare the cell adhesion affinity to the polymer with and without collagen, cell growth experiments were performed. The results showed that collagen improves the cell adhesion onto the polymer surface. With the increasing amount of collagen, cell viability increases 86% (ECV304, p < 0.05) and 83% (3 T3, p < 0.05). Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
25.
Roemeria refracta DC. (Papaveraceae) of Turkish origin yielded two novel epimeric N-oxides, (?)-(5R, 11S,14R)-reframidine N-oxide ( = (?)-(5R, 11S,14R)-11,12-dihydro-14-methyl-11,5-(iminomethano)-5H -cyclohepta[1, 2-f: 4, 5-f′]bis[1,3]benzodioxole 14-oxide; 1 ) and (?)-(5R, 11S, 14S)-reframidine N-oxide ( = (?)-(5R, 11S, 14S)-11, 12-dihydro-14-methyl-11, 5-(iminomethano)-5H-cyclohepta[1, 2-f:4, 5-f′]bis[1, 3]benzodioxole 14-oxide; 2 ). The isolated (?)-roelactamine ( = (?)-11, 12-dihydro-14-methyl-11, 5-(iminomethano)-5H-cyclohepta[1, 2-f:4, 5-f′]bis[1, 3]benzodioxol-15-one, 4 ) is the first natural isopavinoid incorporating a lactam group. The epimeric (?)-15-(2-oxopropyl)reframidines ( = (?)-1-[11, 12-dihydro-14-methyl-11, 5-(iminomethano)-5H-cyclohepta[1, 2-f:4, 5-f′]bis[1, 3]benzodioxol-15-y1]propan-2-ones; 5/6 ) and the epimeric (?)-ethyl (reframidin-15-yl)acetates ( = (?)-ethyl [11, 12-dihydro-14-methyl-11, 5-(iminomethano)-5H-cyclohepta[1, 2-f:4, 5-f′]bis[1, 3]benzodioxol-15-y1]acetates; 7/8 ) are probably artifacts. (±)-Coclaurine ( 9 ), (±)-N-methylcoclaurine ( 10 ), (?)-roemeridine ( 11 ), and N-feruloyltyramine ( 12 ) are also isolated from R. refracta together with the previously reported bases. Specific 13C-NMR assignments are reported for the first time for the isopavines. 相似文献
26.
Alexey Kirilin Serap Sahin Päivi Mäki‐Arvela Johan Wärnå Tapio Salmi Dmitry Yu. Murzin 《国际化学动力学杂志》2010,42(10):629-639
The kinetics of the acylation of (R,S)‐1‐phenylethanol was investigated using lipase as a catalyst. The main parameters were temperature, reaction atmosphere, different acyl donors, and different amounts of acyl donor as well as the presence of some additives in the reaction mixture. The initial reaction rate increased with increasing temperature and with a decreasing amount of an acyl donor. The activated esters, such as isopropenyl‐ and vinyl acetate, exhibited very high acylation rates for R‐1‐phenylethanol, whereas low rates were obtained with ethyl acetate and 2‐methoxyethyl acetate. The addition of water and acetophenone decreased the acylation rate. A kinetic model was developed based on a sequential step mechanism, in which enzyme was reacting in the first step with an acyl donor followed by the reaction of a modified enzyme complex with the reactant, R‐1‐phenylethanol. Comparison with experimental data obtained at different temperatures allowed simplification of this model, leading to a kinetic equation with just one apparent parameter. The influence of the amount of acyl donor, ethyl acetate, could be quantitatively described by taking into account the competitive inhibition of the ethanol produced. The rate constants and apparent activation energy for experiments performed under different temperatures and the amounts of acylation agent were determined. The apparent activation energy was 24.5 kJ/mol. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 629–639, 2010 相似文献
27.
Serap Beli Simon J. Coles Derya Davarc David B. Davies Michael B. Hursthouse Adem Kl 《Polyhedron》2007,26(18):5283-5292
Reaction of cyclophosphazene, N3P3Cl6 (1), with the sodium derivative of the fluorinated diol, 2,2,3,3,4,4-hexafluoropentane-1,5-diol (2), in THF solution at room temperature afforded five isolated products, whose structures have been characterised by X-ray crystallography and 1H, 19F and 31P NMR spectroscopy: the mono-spiro compound, N3P3Cl4(OCH2CF2CF2CF2CH2O) (3), its ansa isomer (4), a di-spiro derivative N3P3Cl2(OCH2CF2CF2CF2CH2O)2 (5), its spiro-ansa (6) isomer and the tri-spiro compound N3P3(OCH2CF2CF2CF2CH2O)3 (7). Quantitative 31P NMR measurements of the soluble portion of the reaction mixture show that in the reaction of (1) with the sodium derivative of the fluorinated pentanediol (2) there is a small preference for spiro compounds compared to ansa compounds (ratio ca. 1.3:1), similar to the analogous reaction of (1) with the sodium derivative of the fluorinated butanediol where there is a slightly greater proportion of spiro compared to ansa compounds (ratio ca. 1.5:1). The relative proportions of spiro and ansa compounds is likely to depend on the fine balance in stabilities of the different medium-sized rings in the fluorinated pentanediol (spiro, 8- and ansa, 10-membered rings) compared to the fluorinated butanediol (spiro, 7- and ansa, nine-membered rings) derivatives of cyclophosphazene. 相似文献
28.
Beşli S Davies DB Kiliç A Shaw RA Sahin S Uslu A Yeşilot S 《Journal of chromatography. A》2006,1132(1-2):201-205
High-performance liquid chromatographic (HPLC) methods have been developed for investigating the stereogenic properties of two analogous series of dibenzylamino derivatives of cyclotriphosphazene containing either one or two equivalent stereogenic centres. Separation of the enantiomers of all the racemic compounds has been investigated by chiral HPLC using Whelk-01 and Chiralcel OD columns. In all cases, conditions for separation of enantiomers have been found using a Whelk-01 column with different ratios of tetrahydrofuran in n-hexane as the mobile phase. It is found that both the separation factor (alpha) and resolution factor (R(S)) of molecules with two equivalent stereogenic centres are greater than those for analogues with only one centre. 相似文献
29.
Betül en Serap Alp Gülsiye
ztürk Muhittin Aygün Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):o223-o224
Molecules of the title compound, C24H19NO6S, adopt the Z configuration and have a distorted tetrahedral geometry around the S atom. The oxazolone, 2‐phenyl and methoxyphenyl rings are approximately coplanar. The C atom between the methoxyphenyl and oxazolone rings displays a distorted trigonal bonding geometry. Pairs of molecules are linked into dimers through weak C—H⋯O hydrogen bonds. 相似文献
30.
Omer L. Gebizlioglu Serap Yörübulut 《Methodology and Computing in Applied Probability》2016,18(4):1043-1064
Pareto distributions are very flexible probability models with various forms and kinds. In this paper, a new bivariate Pseudo-Pareto distribution and its properties are presented and discussed. Main variables, order statistics and concomitants of this distribution are studied and their importance for risk and reliability analysis is explained. Joint and marginal distributions, complementing cumulative distributions and hazard functions of the variables are derived. Numerical illustrations, graphical displays and interpretations for the obtained distributions and derived functions are provided. An implementation example on defaultable bonds is performed. 相似文献