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81.
用色质联用(GC/MS)法测定酱香型酒空杯香的化学成分,鉴定出13种化合物,并测定了它们的相对含量,其中以十六酸乙酯、油酸乙酯、亚油酸乙酯为主。  相似文献   
82.
This paper deals with a class of three-dimensional autonomous nonlinear systems which have potential applications in secure communications, and investigates the localization problem of compact invariant sets of a class of Lorenz-like chaotic systems which contain T system with the help of iterative theorem and Lyapunov function theorem. Since the Lorenz-like chaotic system does not have y in the second equation, the approach used to the Lorenz system cannot be applied to the Lorenz-like chaotic system. We overcome this difficulty by introducing a cross term and get an interesting result, which includes the most interesting case of the chaotic attractor of the Lorenz-like systems. Furthermore, the results obtained in this paper are applied to study complete chaos synchronization. Finally, numerical simulations show the effectiveness of the proposed scheme.  相似文献   
83.
84.
This paper deals with the robust fault detection filter (RFDF) design problems for uncertain nonlinear Markovian jump systems with unknown input. By using a observer-based fault detection filter as residual generator, the RFDF design is formulated as an HH-filtering problem. Particularly, two different Markov processes are considered for modeling the randomness of system matrix and the state delay. With the aid of the weighting matrix function, the design objective is to find an optimal RFDF, which results in a minimal difference between the reference model and the RFDF to be designed. By using a new convex polyhedron technique and two mode-dependent Lyapunov functional, some new sufficient conditions are established in terms of delay-dependent linear matrix inequalities (LMIs) to synthesize the residual generation scheme. Finally, a numerical example is given to illustrate the effectiveness of the proposed techniques.  相似文献   
85.
In this article, we consider a two-component nonlinear shallow water system, which includes the famous 2-component Camassa-Holm and Degasperis-Procesi equations as special cases. The local well-posedess for this equations is established. Some sufficient conditions for blow-up of the solutions in finite time are given. Moreover, by separation method, the self-similar solutions for the nonlinear shallow water equations are obtained, and which local or global behavior can be determined by the corresponding Emden equation.  相似文献   
86.
Methyl-2-nitrophenols can be emitted directly to the atmosphere or can be formed in situ via the oxidation of aromatic hydrocarbons. Nitrophenols possess phytotoxic properties and recent studies indicate their photooxidation is effective in producing secondary organic aerosols. Therefore, investigations on the major photooxidation pathways of these compounds with respect to assessing their environmental impacts and effects on human health are highly relevant. Presented here are determinations of the rate coefficients for the reactions of OH radicals with four methyl-2-nitrophenol isomers using a relative kinetic technique. The experiments were performed in a 1080 l photoreactor at (760 +/- 10) Torr total pressure of synthetic air at (296 +/- 3) K. The following rate coefficients (in units of cm(3) molecule(-1) s(-1)) have been obtained: 3-methyl-2-nitrophenol, (3.69 +/- 0.70) x 10(-12); 4-methyl-2-nitrophenol, (3.59 +/- 1.17) x 10(-12); 5-methyl-2-nitrophenol, (6.72 +/- 2.14) x 10(-12); 6-methyl-2-nitrophenol, (2.70 +/- 0.57) x 10(-12). Photolysis of the methyl-2-nitrophenols with the superactinic fluorescent lamps (320 < lambda < 480 nm, lambda(max) = 360 nm) used in the experiments was observed. Photolysis frequencies measured for the methyl-2-nitrophenols in the photoreactor have been determined and scaled to atmospheric conditions. The results suggest that photolysis rather than the reaction with OH radicals will be the dominant gas phase atmospheric loss process for methyl-2-nitrophenols.  相似文献   
87.
The changes of focusing structure parameters caused by the DC-clearing electric field of storage ring were researched. The conclusion is made that tune shift caused by the DC-clearing electric field is related to the real-time close orbit of stored beam. The clearing electric field asymmetrically distributed along the ring destroys the symmetry of the focusing structure and decreases the acceptance of storage ring. It has negative effect to the injection and accumulation process in certain condition.  相似文献   
88.
γ射线辐照超细铂催化剂的载体效应   总被引:5,自引:0,他引:5  
用γ射线辐射法制备了铂溶胶和粒径为5nm的超细铂粉,采用机械混合法和溶胶-凝胶法制备了一系列不同载体的超细铂催化剂,不同载体对提高CO氧化活性的顺序为:MgO〉γ-Al2O3≥ZrO2〉TiO2〉SiO2,其中,由溶胶-凝胶法制备的0.1%Pt/SiO2和0.1%Pt/TiO2的经表面积大,Pt分散度高,但活性最差,XPS结果表明部分表面Pt^0和TiO2作用生成了PtO和Ti2O3,并且Pt的分  相似文献   
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