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221.
AbstractIn this paper, we propose hybrid implicit and explicit viscosity iterative algorithms for solving general hierarchical fixed-point problems for a countable family of non-expansive mappings in uniformly smooth Banach spaces. These hybrid viscosity algorithms are based on the well-known viscosity approximation method and hybrid steepest-descent method. We obtain some strong convergence theorems under suitable conditions. Our results extend, improve, supplement and develop the recent results in the literature. 相似文献
222.
A. J. Saleh Ahammad Subrata Sarker Md Aminur Rahman Jae‐Joon Lee 《Electroanalysis》2010,22(6):694-700
A selective and very simple electrochemical method, based on anodization of a glassy carbon electrode (GCE), was developed for the simultaneous detection of hydroquinone (HQ) and catechol (CT). It was found that the activated GCE showed an excellent catalytic behavior and enhanced reversibility towards the oxidation of both HQ and CT. The redox responses from the mixture of HQ and CT were easily resolved at an activated GCE. The detection limits for HQ and CT were calculated to be 0.16 and 0.11 μM, respectively. The activated GCE was successfully examined for real sample analysis with tap water and it showed a stable and reliable recovery data. 相似文献
223.
In a continuation to our study on the marine sponge Haliclona species we have isolated three new cytotoxic components of sphingolipids (1-3). Methanolysis of the sphingolipid 1a-d in methanol produces fatty acid methyl ester. GC/MS was used to determine the length. The structure of each isolated compound has been determined on the basis of spectroscopic data and chemical evidence. 相似文献
224.
Haza Saleh Alayachi M. S. M. Noorani E. M. Elsayed 《Journal of Applied Analysis & Computation》2020,10(4):1343-1354
In this paper, we will investigate some qualitative behavior of solutions of the following fourth order difference equation $x_{n+1}=ax_{n-1}+\frac{bx_{n-1}}{cx_{n-1}-dx_{n-3}},$ \ $n=0,1,...,$ where the initial conditions $x_{-3,}x_{-2},\ x_{-1}$\ and\ $x_{0}\ $are arbitrary real numbers and the values $a,\ b,\ c\ $and$\;d$ are\ defined as positive real numbers. 相似文献
225.
Ziad Moussa Saleh A. Ahmed Ahmad S. ElDouhaibi Shaya Y. Al-Raqa 《Tetrahedron letters》2010,51(14):1826-9126
NMR Studies on the reaction of triphenylphosphine with various amounts of triflic anhydride at 0 °C is described. The reagent structure resulting from mixing 1.3 equiv of Ph3P with Tf2O (1.0 mmol) has been established as an equilibrium mixture consisting mainly of triphenyl(trifluoromethylsulfonyloxy)phosphonium trifluoromethanesulfinate and the corresponding bis(triphenyl)oxodiphosphonium trifluoromethanesulfinate dimer. The electrophilic properties of the system have been exploited in the development of a mild method for converting aldoximes into nitriles. The dehydration occurs at 0 °C under very mild conditions by initial activation of the oxime oxygen, followed by treatment with a base and subsequent elimination of triphenylphosphine oxide. The substrate scope and functional group tolerance of this useful method are explored. 相似文献
226.
Hussein Samma Chee Peng Lim Junita Mohamad Saleh Shahrel Azmin Suandi 《Memetic Computing》2016,8(3):235-251
In this paper, a novel fuzzy support vector machine (FSVM) coupled with a memetic particle swarm optimization (MPSO) algorithm is introduced. Its application to a license plate recognition problem is studied comprehensively. The proposed recognition model comprises linear FSVM classifiers which are used to locate a two-character window of the license plate. A new MPSO algorithm which consists of three layers i.e. a global optimization layer, a component optimization layer, and a local optimization layer is constructed. During the construction process, MPSO performs FSVM parameters tuning, feature selection, and training instance selection simultaneously. A total of 220 real Malaysian car plate images are used for evaluation. The experimental results indicate the effectiveness of the proposed model for undertaking license plate recognition problems. 相似文献
227.
In this paper, the behavior of a fractional order Van der Pol-like oscillator is investigated using a describing function method. A parametric function for the boundary between oscillatory and nonoscillatory regions of this system is extracted. The analytical results are evaluated by numerical simulations which demonstrate sufficient reliability of the proposed analyzing method. 相似文献
228.
229.
Zahra JA el-Abadelah MM Nazer MZ Ebraheem KA Boese R 《Organic & biomolecular chemistry》2003,1(10):1798-1801
The tautomerism of 4-methyldihydro-1,3,4-benzotriazepin-5-ones (2,3) is re-investigated by means of X-ray diffraction and quantum chemical calculations. The data revealed that the model compound (2a) exists in the amidrazone 1,4-dihydro tautomeric form (A), but not in the alternate 3,4-dihydro tautomer (B) as was previously reported. 相似文献
230.
Takacs JM Schroeder SD Han J Gifford M Jiang XT Saleh T Vayalakkada S Yap AH 《Organic letters》2003,5(20):3595-3598
[reaction: see text] Screening combinations of five catalyst precursors with 13 phosphorus ligands identified cyclization catalysts that favor carbocyclization-trapping with N-hydroxyphthalimide over a competing cycloisomerization mode. 相似文献