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This paper considers the global finite-time output feedback stabilization of a class of nonlinear highorder feedforward systems. By using the homogeneous domination method together with adding a power integrator method and overcoming several troublesome obstacles in the design and analysis, a global finitetime output feedback controller with reduced-order observer is recursively designed to globally finite-time stabilize nonlinear high-order feedforward systems. [ABSTRACT FROM AUTHOR]

This paper investigates the global stabilization for a class of high-order time-delay nonlinear systems. Compared with the existing references, a distinct characteristic of this paper rests in time-delay entering high-order, low-order, and linear growth parts of system nonlinearities. Based on Lyapunov-Krasovskii theorem and necessary improvement of the adding a power integrator method, a continuous global state-feedback controller is constructed to preserve the equilibrium at the origin and guarantees the global asymptotic stability of the resulting closed-loop system. Finally, a simple example is provided to demonstrate the validness of the proposed approach. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper studies the state feedback control problem for a class of nonlinear systems with high-order and low-order nonlinearities. The introduction of the sign function together with the method of adding a power integrator and Lyapunov stability theorem makes the closed-loop system globally asymptotically stable. Exploiting the idea of how to deal with growth nonlinearities with both high order and low order being relaxed to some intervals is the focus of this work. [ABSTRACT FROM PUBLISHER]

Abstract: In order to explore the new and efficient cyclopropanation reagents, a theoretical investigation of the cyclopropanation reactions of aluminum carbenoid Cl2AlCH2Cl with olefins was given at the B3LYP level of theory. All of the reactions examined displayed similar concerted mechanisms for the cyclopropanation of these reagents. The reactions are predicted to be highly chemical reactivity with low barriers and could be favored in experiment, and the cyclopropanation reaction proceed easily at lower temperature. The computational results are briefly compared to other carbenoid reactions and related species. [Copyright &y& Elsevier]

Abstract: In order to explore the new and efficient cyclopropanation reagents, a theoretical investigation of the cyclopropanation reactions of titanium carbenoid PhOTiCl2CH2Cl and Cl3TiCH2Cl with olefins was given at the B3LYP level of theory. All of the reactions examined displayed similar concerted mechanisms for the cyclopropanation of these reagents. The reactions are predicted to be highly chemical reactivity with low barriers and could be favored in experiment, and the cyclopropanation reaction proceed easily at lower temperature. The computational results are briefly compared to other carbenoid reactions and related species. [Copyright &y& Elsevier]

Abstract: The mechanisms for the abstraction reactions of germylenes with oxirane and thiirane have been characterized in detail using density functional theory. All the stationary points were determined at the B3LYP/6-311++G (d, p) level of the theory. As a result, our theoretical investigations suggest that, irrespective of deoxygenation and desulfurization, the alkyl-substituted germylene abstractions are much more favorable than those of the π-donor-substituted germylenes. Moreover, for a given germylene, the desulfurization reaction is more exothermic as well as more kinetically favorable. Furthermore, a configuration mixing model based on the work of Pross and Shaik is used to rationalize the computational results. A comparison with carbene and silylene also led to the same result and the results obtained allowed a number of predictions to be made. [Copyright &y& Elsevier]

Abstract: The mechanisms for the insertion reactions of alkylidenecarbenes with CH3O–H have been investigated at the B3LYP/6-311G(d,p) level of the theory. According to our model calculations these insertion reactions will easily yield vinyl ether products and for a given single substituted alkylidenecarbene will yield cis–trans-isomer mixture. Moreover the reactivity of alkylidenecarbene decreases in the order: HFCsp="0.25" />>HClCsp="0.25" />>HBrCsp="0.25" />>H(CH3)Csp="0.25" />>H2Crmore, a configuration mixing model based on the work of Pross and Shaik is used to rationalize the computational results. [Copyright &y& Elsevier]

The detection of gas pollutants in atmosphere and indoor air is very important to human health and safety. Monoxide carbon (CO) is a common gas pollutant with high toxicity that mainly comes from the inadequacy oxidization of carbon such as oil, coal and petrol inadequacy combustion, auto-gas and some natural disasters whose limit value in air is lower than 6.0 mg·m-3 in the national standard. Due to its toxicity and uneasy detection, it is one of very dangerous component in the silent killer. Recently, several methods, including infra-red absorption, gas chromatography, potentiometry, Hg replacement, spectrophotometry, I2O5 and PdCl2 nake-eye, semiconductor sensor have been reportedly used for the detection of CO. To our best knowledge, there are no SPR absorption methods for CO, based on the NG SPR absorption. In this paper, the reaction between CO and HAuCl4 was studied with absorption spectrophotometry and transmission electron microscopy (TEM)while a simple and rapid SPR absorption method was developed for the determination of trace CO. In pH 7.2 phosphate buffer solutions, monoxide carbon reduced HAuCl4 to form nanogold (NG) particles with the size of about 45 nm that exhibited surface plasmon resonance (SPR) absorption peak at 540 nm and three energy spectral peaks at 1.70 keV, 2.20 and 9.70 keV for gold element. The analytical conditions were examined, and a pH 7.2 phosphate buffer solution with a concentration of 40 mmoL·L-1 PO3-4, a concentration of 40.0 μg· mL-1 HAuCl4 and a reaction time of 5 min was selected for use. Under the selected conditions, the SPR absorption peak value was linear to CO concentration in the range of 0.2～8.75 μg· mL-1, with a detection limit of 0.1 μg· mL-1 CO. According to the procedure, the influence of coexistent substances on the determination of 1.0 mg·L-1 CO was tested, with a relative error of ±5%. Results indicated that 200 times SO2-3, PO3-4, SO2-4, CO2-3 and NO-3, 100 times Zn2+, K+, BrO-3, Na2S, ethanol, methanol, 80 times Ni2+, Cr3+, Co2+, Ca2+, Mg2+, Fe3+, glucose, Pb2+, Al3+, SeO2-3, Na2S2O3, formaldehyde, 50 times Mn2+ do not interfere with the determination. It showed that this SPR method had good selectivity. The CO content in air samples was determined with the SPR method, with a relative standard deviation (RSD) of 1.8%～4.2%, the SPR method results were agreement with that of the gas chromatography (GC).