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Selective catalytic reduction (SCR) technology widely used for reducing the nitrogen emissions of coal-fired power plants. This work builds a dynamic model of a SCR denitrification system with a hybrid structure in use of two approaches. In the first approach, the dynamics of the SCR reaction over the catalyst surface is investigated, the mechanism model is developed, and the model parameters are identified particle swarm optimization algorithm. In the second approach, a data-driven model is developed as an error compensation model based on the least squares support vector machines method. These two approaches lead to the development of a hybrid dynamic model that can accurately describe the dynamic operation process of the SCR denitrification system and is validated by using actual data from field unit operations.

Gadoped ZnO(GZO) thin films were grown on single crystal silicon(111) and quartz glass substrates by pulsed laser deposition(PLD) method at different substrate temperatures from room temperature to 750 ℃.The change of substrate temperature leads to different diffusion and desorption rates for adsorption atoms resting on substrate surface,and results in different crystalline quality for GZO thin films.The GZO thin film grown at 450 ℃ has the best crystalline quality.The carrier concentration monotonically decreases with the increase of substrate temperature,which is related to the intrinsic defects in films.The Hall mobility first increases and then decreases with the substrate temperature increasing,it results from the variation of grain boundary scattering.And the lowest resistivity ~0.02 Ω·cm is obtained in the film prepared at 450 ℃.With the increase of substrate temperature,the optical band gap becomes narrow due to the monotonic increase of carrier concentration.The average transmittance in visible region is above 85% for all the GZO samples.Our results exhibit that the optical and electrical properties of GZO thin films prepared by PLD method can be adjusted by the change of substrate temperature.

Selective catalytic reduction (SCR) is widely applied in coal-fired power plants. SCR process is a complex physical and chemical process with multi-input, strong coupling, nonlinear, and time delay characteristics. An effective model is the basis of conducting control and optimization. In this paper, influencing factors of catalytic reaction in SCR converter are analyzed and five measurable parameters are selected as the model input variables. NOx emission and NH 3 slip are separately taken as output variables. The LSSVM algorithm is employed to build the SCR models using real plant operation data from a 1000 MW coal-fired boiler. Simulation results have shown satisfied model accuracy and effectiveness are achieved.

Studies on mechanical properties of three-phase asynchronous motor, we usually use Matlab to establish a model to achieve the simulation of the motor mechanical properties. In the process of the actual use, modify large number of parameters will cause many program errors and affect the experimental velocity. By the mixed programming of MATLAB and VB, we can use the feature of visualization interface of VB and the feature of software toolboxes and the function of drawing of Matlab. Combining Characteristics of VB and Matlab and using mixed programming of VB and Matlab to achieve simulation are useful attempts.

Virtualization technology becomes a hot IT technology with the popu-larity of Cloud Computing. However, new security issues arise with it. Specifically, the resources sharing and data communication in virtual machines are most concerned. In this paper an access control model is proposed which combines the Chinese Wall and BLP model. BLP multi-level security model is introduced with corresponding improvement based on PCW (Prioritized Chinese Wall) security model. This model can be used to safely control the resources and event behaviors in virtual machines. Experimental results show its effectiveness and safety.

Objective To investigate the polymorphism of CYP2C9 in patients with atrial fibrillation as well as the possible relationship between the individual warfarin dosage requirements and the genetic polymorphism in Chinese patients. Methods The polymorphism of CYP2C9 in 100 patients with atrial fibrillation in our hospital was detected by using PCR and restriction enzyme digestion. The genotype and allelic frequencies were calculated and the individual warfarin dosage requirements were analysed. Results In this group of patients CYP2C9*1 allele and CYP2C9*3 were detected, The frequency of *1 allele and *3 allele was 96% and 4%, respectively. Two genotypes were detected as well. CYP2C9*1/*1 was the most common genotype, with the frequency of 92%. The frequency of CYP2C9*1/*3 was 4% in these 100 patients. To achieve similar target INR range (2.0–3.0), variant CYP2C9*1/*3 homozygotes or heterozygotes required lower daily mean maintain doses (2.14±0. 55 mg) than wild-type CYP2C9*1/*1 patients did (3. 17±0. 74 mg). Conclusion Polymorphism of CYP2C9 is associated with warfarin dose requirements in 100 patients with atrial fibrillation, which is partly the factor causing difference of individual warfarin dosage requirements.