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More and more comprehensive pipeline corridors are built in the urban cities to avoid the inconvenience effects of traffic jams to people's daily lives that pipelines laying caused and raise the quantity of pipeline management. While, the fire risk degree of comprehensive pipeline corridor is pretty high. This article analyses the fire risk type and characteristics in comprehensive pipeline corridor and discuss some fire safety prevention methods to reduce the loss that fire causes, such as fire partition design, structure material replace, automatic fire detective and extinguish system. High expansion foam system is suggested to be used in the comprehensive pipeline corridor for its low water use and high fire extinguish effect. The water use amount of high expansion foam system and normal water sprinkle system are compared. This advantage of high expansion system also means that the post-disaster recovery efforts are much less than that of normal water sprinkle system. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, by introducing a combined method of sign function, homogeneous domination and adding a power integrator, and overcoming several troublesome obstacles in the design and analysis, the problem of state feedback control for a class of nonlinear high-order feedforward systems with the nonlinearity's order being relaxed to an interval rather than a fixed point is solved. [Copyright &y& Elsevier]

Abstract: A computational study of the [2+2] cycloaddition reaction pathways for formaldehyde–ketene and formaldehyde–isocyanic acid has been presented by using the DFT(B3LYP) method. These cycloaddition reactions could yield to eight different four-membered molecules. In the two considered reactions, the reactions for the β-propiolactone and oxazetidinone products have the lower barriers of 26.40 and 32.88kcalmol−1 and are exothermic by 27.68 and 4.00kcalmol−1, respectively. The β-propiolactone and oxazetidinone ring compounds have been predicted to be the most stable thermodynamically. Simulation of the solvent environment (toluene, THF, acetone, acetonitrile and water) has been investigated by using polarized continuum model method, yet only small differences have been found to occur in energetics between the studied structures in the gas-phase and in the solvent. [Copyright &y& Elsevier]

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: A computational study of methane to methanethiol Conversion by first-row transition-metal sulfide ion reactions of MnS+ with CH4 is presented. The reaction proceeds through two competing pathways: pathway A via intermediate formation of CH3MnSH+ (IM2). The second pathway, which leads to the insertion isomer HMnSCH3 + (IM4). Both pathway barriers to reactions become systematically lower as quintet state system(47.52 and 67.66 kJmol−1 for pathway A and pathway B, respectively). In contrast, the reaction barriers for septet state via both pathway remain high (>125kJmol−1). Mn+ and MnSH+ are formed as major ionic products in the reaction of MnS+ with CH4, The computational results are briefly compared to other 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]