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111.
Gulay Zengin Zehra Nalbantbasi Huseyin Zengin Hasan Turkmen 《Heteroatom Chemistry》2011,22(6):707-714
A novel series of cannabimimetic aminoalkylindole‐based sulfonamide derivatives was synthesized. These new compounds were synthesized by reacting acyl chlorides of naphthoic acids with deacetylated acetazolamide in the presence of N‐ethyl‐morpholine to give structures incorporating 1‐naphthoyl groups of cannabimimetic aminoalkylindoles and a five‐membered heteroring typical of antiglaucoma sulfa drugs. The synthesized compounds were characterized using standard techniques. Photoluminescence of these derivatives was also studied, where more electron‐donating groups on the aromatic ring at the para‐position caused an increase in the intensity of the main peaks and shifts to higher emission wavelengths. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:707–714, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20738 相似文献
112.
1-(11-Benzoyl-11-azatricyclo[6.2.1.02,7]undeca-2,4,6,9-tetraen-1-yl)ethanone was synthesized by cycloaddition of 2-acetyl-N-benzoylpyrrole to benzyne. Direct photolysis of 1-(11-benzoyl-11-azatricyclo-[6.2.1.02,7]undeca-2,4,6,9-tetraen-1-yl)ethanone in benzene gave N-(4-acetylnaphthalen-1-yl)benzamide. The formation of this product is discussed in terms of radical-stabilizing and destabilizing
effect of electron-withdrawing group in the formation of cyclopropane ring.
Published in Russian in Zhurnal Organicheskoi Khimii, 2009, Vol. 45, No. 4, pp. 626–629.
The text was submitted by the authors in English. 相似文献
113.
Hongbo Yu Mustafa Ozturk Pakize Demirel Huseyin Cakmak Ekmel Ozbay 《Journal of Crystal Growth》2010,312(23):3438-3442
Non-polar a-plane GaN film with crystalline quality and anisotropy improvement is grown by use of high temperature AlN/AlGaN buffer, which is directly deposited on r-plane sapphire by pulse flows. Compared to the a-plane GaN grown on AlN buffer, X-ray rocking curve analysis reveals a remarkable reduction in the full width at half maximum, both on-axis and off-axis. Atomic force microscopy image exhibits a fully coalesced pit-free surface morphology with low root-mean-square roughness (∼1.5 nm). Photoluminescence is carried out on the a-plane GaN grown on r-plane sapphire. It is found that, at low temperature, the dominant emission at ∼3.42 eV is composed of two separate peaks with different characteristics, which provide explanations for the controversial attributions of this peak in previous studies. 相似文献
114.
本文首先对电磁理论中的对偶对称性以及对偶变换做了简要回顾.然后讨论了与电磁相互作用相联系的Aharonov-Casher和He-McKellar-Wilkens相位之间的对偶对称性.最后,在宇称不守恒但具有相对论不变性的条件下,给出了一般情况下描述Aharonov-Casher和He-McKellar-Wilkens相位之间对偶对称关系的拉格朗日量,从而建立了统一的、不依赖于模型的描述Aharonov-Casher和He-McKellar-Wilkens相位之间对偶对称关系的方法. 相似文献
115.
Huseyin Tas Lon J. Mathias 《Journal of polymer science. Part A, Polymer chemistry》2008,46(23):7785-7793
New ether dimer (ED‐Od) and diester (ODE) derivatives of α‐hydroxymethylacrylate, each having two octadecyl side chains, were synthesized and (co)polymerized to evaluate the effects of differences in the structures of the monomers on final (co)polymer properties, particularly glass transition temperature. The free radical polymerizations of both monomers yielded high‐molecular weight polymers. Cyclopolymer formation of ED‐Od was confirmed by 13C NMR analysis and the cyclization efficiency (0.95 or greater) was found to be as high as the cyclization efficiencies of the cyclopolymerizations of ether dimers of various alkyl α‐hydroxymethylacrylates synthesized previously. Copolymers of both ED‐Od and ODE with methyl methacrylate (MMA) showed significant Tg decreases over PMMA due to octadecyl side groups causing “internal” plasticization. Comparison of the Tg's of the copolymers of octadecyl methacrylate, ED‐Od and ODE with MMA revealed that the impacts of these monomers on depression of Tg's are identical. That is, the magnitude of decrease in Tg's was quantitatively related to the number of the octadecyl side groups in the copolymers rather than their placement on the same or randomly incorporated repeat units. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7785–7793, 2008 相似文献
116.
Selman Akbulut 《Proceedings of the American Mathematical Society》1999,127(11):3413-3419
A splitting of a manifold in Kirby's problem list (no. 4.97) is given.
117.
In this paper we study nonlinear second order differential equations subject to separated linear boundary conditions and to
linear impulse conditions. Sign properties of an associated Green’s function are investigated and existence results for positive
solutions of the nonlinear boundary value problem with impulse are established. Upper and lower bounds for positive solutions
are also given. 相似文献
118.
Approximate construction of the set of trajectories of the control system described by a Volterra integral equation
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Nesir Huseyin Khalik G. Guseinov Vladimir N. Ushakov 《Mathematische Nachrichten》2015,288(16):1891-1899
In this paper the set of trajectories of the control system is investigated. It is assumed that the behavior of the control system is described by a Volterra integral equation which is nonlinear with respect to the state vector and is affine with respect to the control vector, and the control functions have an integral constraint. An approximation of the set of trajectories by the set which consists of a finite number of trajectories is given. The Hausdorff distance between the set of trajectories of the system and the set, consisting of a finite number of trajectories is evaluated. 相似文献
119.
Electroinitiated polymerization of acrolein has been achieved by controlled potential electrolysis at the reduction peak potential of the monomer for direct electron transfer. Kinetics and type of mechanism of the polymerization have been investigated. the structure of the polymer has also been examined by IR spectroscopy. in a separate experiment, a small amount of CCI4 was added to a polymerization system. Since the reduction peak potential of CCI4 appears at a more anodic region than that of acrolein on mercurized platinum, initiation proceeds via the electrolytic product of CCI4. the direct and indirect initiation mechanisms are compared. It is found that electroinitiated polymerization of acrolein carried out by direct electron transfer from cathode to monomer (in the absence of CCI4) proceeds simultaneously via radical and anionic mechanism. 相似文献
120.
Songul Akbulut Barbara Krupińska Anna Worobiec Ugur Cevik Halim Taskın Rene Van Grieken Lucyna Samek Ewa Wiłkojć 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1567-1573
PM-10, PM-2.5 and PM-1.0 concentrations were measured over an 8 h period at sites both inside and outside the museum of Wawel Royal Castle in Cracow, Poland. Gross alpha (α) and beta (β) activities seemed to vary across the particle size range with generally higher levels of activities in the PM-2.5 particle fraction, and higher activities in the PM-10 fraction, while both the highest and the lowest beta activities were found in PM-1.0 fraction. However, statistically there was no significant difference. The highly radioactive PM-1.0 fraction comprised mainly 210Pb and the 210Pb progeny, 210Bi and 210Po, and can be attributed to anthropogenic sourced outdoor radioactive particles brought indoors by visitors. 210Pb is considered to be a good tracer of secondary aerosols produced by gas-to-particle conversion. Inside the Museum, the highest level of gross alpha activity was detected in the PM-10 fraction, and was mainly due to the uranium isotopes (234U, 235U and 238U) and their daughter products (226Ra, 232Th, 210Po or 224Ra), and 137Cs. The minimum and maximum total indicative doses per 8 h are caused by 137Cs and 232Th, respectively. 相似文献