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71.
Chaotic behavior of logistic map in superior orbit and an improved chaos-based traffic control model
With a vital role of discrete chaos, standard logistic map has found a celebrated place in the dynamics of chaos theory and in various applications of science, such as a discrete traffic flow model, image encryption in cryptography, secure communication, and weather forecasting. Traditionally, this discrete chaos is controlled by one parameter \(\lambda \) using Picard orbit, a one-step feedback procedure. This article presents a one-step forward, applying Mann orbit (superior orbit) the chaotic properties such as period-doubling, period-3 window, and Lyapunov exponent of the standard logistic map is investigated. The results are illustrated analytically and experimentally followed by concluding remarks and a few counter examples. Due to the extra degree of freedom in parameter \(\lambda \), the map provides improved chaotic properties that increases the performance of dynamical phenomena. Moreover, this study describes an improved chaos-based discrete traffic control model. Surprisingly, added new parameter \(\alpha \) in Mann orbit works as control variable that increases the stability performance of the traffic model. 相似文献
72.
Co-HfO(2) granular films with varying numbers of bilayers were studied by means of transmission electron microscopy (TEM), magnetization loops and zero-field-cooled and field-cooled (ZFC-FC) magnetization. Grain size properties inferred from the measurement techniques were found to be different from those observed from TEM. We show that a modified Langevin function that accounts for dipolar interactions reconciles grain size properties observed by TEM. The mean blocking temperature seen from ZFC-FC analysis was observed to be greater compared to that inferred from TEM data. Moreover, it exhibited a trend with increasing numbers of bilayers. We proposed an explanation for these differences on the basis of the degree of dipolar interactions. 相似文献
73.
Whole cells of Candida parapsilosis ATCC 7330 were used for the resolution of N-acetyl amino acid esters. Excellent enantioselectivities (E = 40 to >500) were achieved for the resolution of N-protected protein and non-protein amino acid esters giving good yields (28–50%) and high enantiomeric excesses (up to >99%) for both enantiomers. 相似文献
74.
Sahu PK Kulkarni BD Khomane RB Pardhy SA Phalgune UD Rajmohanan P Pasricha R 《Chemical communications (Cambridge, England)》2003,(15):1876-1877
Barium hexaaluminate (BHA) synthesized by coupling of sol-gel process in reverse microemulsions shows a unique nanowhisker morphology and high surface area, which are retained after calcination at 1300 degrees C. 相似文献
75.
Primary amines were immobilized on (4-formyl-3,5-dimethoxyphenoxy)methylpolystyrene resin via reductive amination. Attachment of two different 4-chloro-2-methylthiopyrimidines, followed by sulfide oxidation, led to their corresponding sulfone intermediates. Aromatic nucleophilic substitution with various anilines or heteroaromatic amines in the presence of trimethyl aluminum afforded the desired 2,4-diaminopyrimidines after acidic cleavage from the resin. The synthetic methodology described herein was validated with the synthesis of a small 162-member library. 相似文献
76.
This paper reports the synthesis and liquid petroleum gas (LPG) sensing properties of nano-sized cadmium oxide (CdO). The nano-sized CdO powder was successfully synthesized by using a chemical co-precipitation method using cadmium acetate and the ammonium hydroxide, as starting materials and water as a carrier. The resulting nano-sized powder was characterized by X-ray diffraction (XRD) measurements and the transmission electron microscopy (TEM). The LPG sensing properties of the synthesized nano-sized CdO were investigated at different operating temperatures and LPG concentrations. It was found that the calcination temperature and the operating temperature significantly affect the sensitivity of the nano-sized CdO powder to the LPG. The sensitivity is found to be maximum when the calcination temperature was 400 °C. The sensitivity to 75 ppm of LPG is maximum at an operating temperature 450 °C and it was found to be ∼341%. The response and recovery times were found to be nearly 3-5 s and 8-10 s, respectively. The synthesized nano-sized CdO powder is able to detect up to 25 ppm for LPG with reasonable sensitivity at an operating temperature 450 °C and it can be reliably used to monitor the concentration of LPG over the range (25-75 ppm). The experimental results of the LPG sensing studies reveal that the nano-sized CdO powder synthesized by a simple co-precipitation method is a suitable material for the fabrication of the LPG sensor. 相似文献
77.
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79.
J F Lawrence R K Chadha H B Conacher 《International journal of environmental analytical chemistry》1983,15(4):303-308
An X-ray fluorescence spectrometric method has been developed for the quantitative determination of iodide in milk which makes use of anion-exchange filters for the isolation and concentration of iodide from the liquid samples. The milk is deproteinized with trichloroacetic acid, filtered then passed through an anion-exchange paper disc to remove the iodide. The disc is removed, dried then analysed by X-ray fluorescence spectrometry. Six samples, consisting of homogenized, 2% fat and skim milk were analysed and found to contain between 0.37-0.67 ppm iodide. Detection limits in milk were estimated to be 0.05 ppm. 相似文献
80.