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1.
Saleh MI  Ahmad M  Darus H 《Talanta》1990,37(7):757-759
A series of chelating reagents, 1-phenyl-3-methyl-4-(2-fluorobenzoyl)-5-pyrazolone, 1-phenyl-3-methyl-4-(3-fluorobenzoyl)-5-pyrazolone and 1-phenyl-3-methyl-4-(4-fluorobenzoyl)-5-pyrazolone, has been synthesized. The extraction of Ln(III), (Ln = La, Eu and Lu) into chloroform with these reagents at 30 +/- 1 degrees has been studied. The composition of the complexes extracted has been determined by the slope method, and the extraction constants K(ex), were measured. The presence of the fluorine atom in the reagents does not make the K(ex), values much different from those obtained with the parent pyrazolone.  相似文献   
2.
This study presents a learning automata-based harmony search (LAHS) for unconstrained optimization of continuous problems. The harmony search (HS) algorithm performance strongly depends on the fine tuning of its parameters, including the harmony consideration rate (HMCR), pitch adjustment rate (PAR) and bandwidth (bw). Inspired by the spur-in-time responses in the musical improvisation process, learning capabilities are employed in the HS to select these parameters based on spontaneous reactions. An extensive numerical investigation is conducted on several well-known test functions, and the results are compared with the HS algorithm and its prominent variants, including the improved harmony search (IHS), global-best harmony search (GHS) and self-adaptive global-best harmony search (SGHS). The numerical results indicate that the LAHS is more efficient in finding optimum solutions and outperforms the existing HS algorithm variants.  相似文献   
3.
In this paper, we introduce new sufficient conditions for certain integral operators to be starlike and p-valently starlike in the open unit disk.  相似文献   
4.
New inequalities of Ostrowski type for functions whose derivatives in absolute value are s-convex in the second sense are obtained.  相似文献   
5.
By making use of the principle of subordination between analytic functions and the Cho–Kwon–Srivastava operator, we introduce a certain subclass of multivalent analytic functions. Such results as subordination and superordination properties, convolution properties, inclusion relationships, distortion theorems, inequality properties and sufficient conditions for multivalent starlikeness are proved. The results presented here would provide extensions of those given in earlier works. Several other new results are also obtained.  相似文献   
6.
This paper presents the experimental works on the active control implementation of a flexibly mounted cylinder exhibiting vortex induced vibration phenomena. The dynamic response of the system was initially studied by fixing single and double passive control rods to the main cylinder. It was found that the fixed control rod could not suppress the vibration for both cases. In fact, the vibration was amplified as compared with the bare cylinder response. By retaining the same position, an active open loop control strategy was introduced to the vibrating system by rotating the single control rod in clockwise and counter clockwise directions. The results indicated that the counter clockwise direction has suppressed the vibration up to 29.81 dB. Further investigation was made by studying the performance of the control rod at several speeds in a single reduced speed of 4.29. It was found that the maximum attenuation level of 19.56 dB was attained based on 1676 RPM of control rod rotating speed. In addition, an overview of attenuation level trends at both varying control speed and reduced speed were presented in this study. Through the experimental implementation of control strategies conducted in this research, it was found that the active control strategy has performed well as suppression strategy at ineffective fixed control rod position.  相似文献   
7.
In this paper we consider the class consisting of analytic functions with negative coefficients and fixed second coefficient. The object of the present paper is to give coefficient estimates, convex linear combinations, some distortion theorems and radii of starlikeness and convexity for f(z) in the class . The work is supported by UKM grant ST-028-2003 and IRPA grant 09-02-02-80 EA208, Malysia. This paper is that of a talk on the “International Conference at Analysis in Theory and Applications” held in Nanjing, P. R. China, July, 2004.  相似文献   
8.
In this paper we consider the class ∑[p, α, β, k, c] consisting of analytic functions with negative coefficients and fixed second coefficient. The object of the present paper is to give coefficient estimates,convex linear combinations, some distortion theorems and radii of starlikeness and convexity for f (z) in the class ∑[p, α, β, k, c].  相似文献   
9.
10.
Wai TS  Darus H  Mohamed N 《Talanta》1996,43(9):1539-1544
The development of hydrometallurgical techniques such as the iron(III) chloride-sodium chloride system for the recovery of metals from scrap materials necessitates the analyses of these metals in a high salt medium during the recovery studies. An alternative method for the analysis of lead and tin in strong brine and high iron systems by flame atomic absorption spectrometry is a microsampling technique in combination with in situ standard addition. Relative standard deviations of 1.2% and 2.2% were obtained for the analysis of lead and tin respectively. The accuracy for the method is also satisfactory with recoveries ranging from 90% to 102%. The microsampling technique is rapid and simple, requires small volumes of sample and offers no clogging problems during the atomic absorption analyses.  相似文献   
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