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61.
Incipient separation over wall irregularities in a steady two dimensional flow field of a perfect fluid which has transonic speed characteristics has been investigated considering viscous-inviscid interactions at high Reynolds number. The aim of this work is to investigate dependence of the critical hump height (when a well attached flow over rigid body surface turns into a separated one) on the Karman–Guderley parameter which characterizes of the local flow field. The analysis of the flow field starts with the so-called inspection analysis of the flow properties and then the interaction problem has been constructed using the asymptotic analysis of triple-deck structure of interaction region. Finally, a method based on a semi-direct solution of governing equations of the transonic interaction problem has been used to obtain the numerical solution of the problem. 相似文献
62.
63.
In this paper, we establish several inequalities for some differantiable mappings that are connected with the Riemann-Liouville fractional integrals. The analysis used in the proofs is fairly elementary. 相似文献
64.
İzzet Amour Morkan Ayşe Uztetik Morkan Çiğdem Tuç Engin Kendi 《Journal of chemical crystallography》2008,38(7):541-545
Abstract Pentacarbonyl(4-methylpyridine)chromium(0) complex was isolated from n-hexane solution as yellow plate-like crystals and characterized by using X-ray crystallography. It crystallizes in the orthorhombic
system with the space group Cmcm and Z = 4. The unit cell parameters are a = 11.737(1) ?, b = 12.857(2) ?, c = 8.465(1) ?. The single crystal X-ray structure of the complex shows that the coordination sphere around the chromium central
atom is slightly distorted octahedron, involving the 4-methylpyridine (4-mp), ligand as a monodentate N-donor ligand and five
carbonyl groups. The four equatorial CO groups in the complex, with the Cr–C2 distance of 1.886 Ǻ, are slightly bent away
from the 4-methylpyridine ligand with the N–Cr–C2 angle of 91.69°. The pyridine ring plane makes an angle of 135.17° with
the Cr–N–CO bond axis. The thermal analysis (differential thermal analysis and thermal gravimetry) and IR spectra of the complex
indicated that the compound undergoes complete decomposition to form the Cr2O3 as the final decomposition product.
Index Abstract The crystal structure of pentacarbonyl(4-methylpyridine)chromium(0) complex has been determined and its thermal behavior has
also been studied.
相似文献
65.
The epoxy resins containing imine bonding were prepared from hydroxyl substituted Schiff base monomers in two steps. At the first step, hydroxyl substituted Schiff base monomers were synthesized via condensation reaction. At the second step, epoxy resins were synthesized from the reaction between Schiff base monomers and epichlorohydrine (EPC). Then curing processes of epoxy resins were achieved by p-phenylenediamine compound. The structures of resulting compounds were confirmed by FT-IR, UV-Vis and 1H-NMR. TG-DTA and DSC measurements were performed for thermal characterizations of the compounds. Chemical resistances of the cured epoxy-amine systems were determined for coating applications in acidic, alkaline and organic solvents. HCl (10%, aqueous solution), NaOH (10%, aqueous solution), DMSO, DMF, N-methylpyrrolidone, ethanol, THF and acetone were used for corrosion tests. Chemical resistance data of the synthesized epoxy resins demonstrated that they have good chemical resistance against various acid, alkaline and common organic solvents. Surface morphologies of epoxy resin and the cured epoxy resin were determined with scanning electron microscopy (SEM) measurements. Also, optical band gap (Eg) values of Schiff base monomers and epoxy resins were calculated from UV-Vis measurements. 相似文献
66.
Journal of Solid State Electrochemistry - A novel hybrid electrochromic material, dyad of poly 4-azidoaniline (PANI-N3) and manganese phthalocyanine bearing terminal alkynyl moieties (TA-MnPc), was... 相似文献
67.
Duygu İNCİ 《应用有机金属化学》2020,34(12):e6016
NOO-type tridentate Schiff base, N-salicylidene-2-aminobenzoic acid, (H2L), and its ternary Cu (II) complex containing H2L Schiff base and 4,7-dimethyl-1,10-phenanthroline (4,7-dmphen), [Cu(4,7-dmphen)(H2L)]27H2O, have been synthesized and characterized by CHN analysis, ESI-MS, FTIR, and single-crystal X-ray diffraction techniques. The interaction of alone H2L Schiff base ligand and ternary Cu (II) complex with biomacramolecules {calf thymus DNA (CT-DNA) and bovine serum albumin (BSA)} has been investigated by electronic absorption and fluorescence spectroscopy. The experimental results indicate that H2L Schiff base ligand and ternary Cu (II) complex bind to CT-DNA by means of a moderate intercalation mode. Furthermore, the fluorescence quenching mechanism between H2L Schiff base ligand and ternary Cu (II) complex with BSA possesses a static quenching process. Radical scavenging activity of H2L Schiff base ligand and ternary Cu (II) complex was measured in terms of EC50, using the DPPH and H2O2 methods. Biomacromolecule interactions and scavenging activity studies revealed that ternary Cu (II) complex yielded better results than H2L Schiff base ligand alone. 相似文献
68.
Duygu Ayyildiz-Tamis Ayse Nalbantsoy Murat Elibol Saime Ismet Deliloglu-Gurhan 《Applied biochemistry and biotechnology》2014,172(1):224-236
In this study, different cultivation systems such as roller bottles (RB), 5-L stirred-tank bioreactor (STR), and disposable bioreactors were used to cultivate hybridoma for lab-scale production of Salmonella Enteritidis O-antigen-specific monoclonal antibody (MAb). Hybridoma cell line was cultivated in either serum-containing or serum-free medium (SFM) culture conditions. In STR, MAb production scaled up to 4 L, and production capabilities of the cells were also evaluated in different featured production systems. Moreover, the growth parameters of the cells in all production systems such as glucose consumption, lactate and ammonia production, and also MAb productivities were determined. Collected supernatants from the reactors were concentrated by a cross-flow filtration system. In conclusion, cells were not adapted to SFM in RB and STR. Therefore, less MAb titer in both STR and RB systems with SFM was observed compared to the cultures containing fetal bovine serum-supplemented medium. A higher MAb titer was gained in the membrane-aerated system compared to those in STR and RB. Although the highest MAb titer was obtained in the static membrane bioreactor system, the highest productivity was obtained in STR operated in semicontinuous mode with overlay aeration. 相似文献
69.
The set of hybrid numbers is a noncommutative number system that unified and generalized the complex, dual, and double (hyperbolic) numbers with the relation ih =− hi =ε+ i. Two hybrid numbers p and q are said to be similar if there exist a nonlightlike hybrid number x satisfying the equality x −1 qx = p . And, it is denoted by p ∼ q . In this paper, we study the concept of similarity for hybrid numbers by solving the linear equations px = xq and qx − xp = c for 相似文献
70.
Ayşe Aktaş Kamiloğlu Duygu Akyüz Atıf Koca İrfan Acar 《Journal of inclusion phenomena and macrocyclic chemistry》2018,92(1-2):223-235
In this study, the new compounds; 3-(4-{[3-(trifluoromethyl)benzyl]oxy}phenyl)propan-1-ol 3 was prepared by the reaction of 4-(3-hydroxypropyl)phenol 1 with 1-(bromomethyl)-3-(trifluoromethyl)benzene 2 and 4-[3-(4-{[3 (trifluoromethyl)benzyl]oxy}phenyl)propoxy] phthalonitrile 5 was synthesized by the reaction of 4-nitrophthalonitrile 4 with 3-(4-{[3-(trifluoromethyl)benzyl]oxy}phenyl)propan-1-ol 3. Novel peripherally tetra substituted H2Pc 6, Co(II) 7, Cu(II) 8, Ni(II) 9 and Fe(II) 10 phthalocyanines, which have peripheral positions with 4-[3-(4-{[3 (trifluoromethyl)benzyl]oxy}phenyl)propoxy] groups, were synthesized and all of the new compounds characterized by IR, 1H NMR, 13C NMR, UV–Vis, mass spectroscopies and elemental analysis. The electrochemical and spectroelectrochemical investigation of the phthalocyanines carrying 4-[3-(4-{[3 (trifluoromethyl)benzyl]oxy}phenyl)propoxy] groups were studied using various electrochemical techniques in DMF on a glassy carbon electrode. Cyclic voltammetry and square wave voltammetry studies show that the complexes have either metal based or ligand-based diffusion controlled electron transfer properties. To shed more light on the electron-transfer steps of the complexes and assignments of the redox couples were carried out by spectroelectrochemical measurements. The color changes during spectral changes of redox species were recorded with in situ electrocolorimetric measurements. The electrochemical and in situ UV–Vis spectral change of complexes indicated their applicability in the fields of the electrochemical technologies. 相似文献