In this paper, MIL53(Fe) was prepared by solvothermal method under different sythetic conditions. The phase structure of samples were characterized by XRD, the morphology and particle size of samples were obtained by SEM, the ultraviolet visible light absorption of samples were explored by UVvis and the band gap energy of samples were calculated from the absorption data. The photocatalytic activities of the samples on Rhodanmine B degradation were investigated. The results show different photocatalytic effects for the samples prepared under different synthetic condition. Accordingly, photocatalytic effect of samples can be controlled through the variation of different synthetic conditions.
Fe site doped L i F e 1-yMg yP O4 was synthesized by mechanical activationonestep solidification method. The structure, morphology and electrochemical properties of the product were investigated by XRD, SEM, CV and galvanostatic charge/discharge determination. The effect of Mg2+doping on electrochemical properties of the samples was discussed. The results show that the crystal structure of LiFePO4 was not changed after proper doping of Mg2+. In the meantime, the proper doping can refine the particle size, and improve the electrical conductivity and reversibility of LiFePO4. Accordingly, the rate performance and the cycling stability of LiFePO4 can be improved effectively. The initial discharge capacity of LiFe0.99Mg0.01PO4 was 158.7 mAh/g at 0.1 C rate and 141.9 mAh/g at 1.0 C rate. And the capacity has almost no attenuation after 50 cycles.
The B i 2S r 2C a( C u 1-xMn x) 2O8+δ( x=0、 0. 0 1、 0. 0 2、 0. 0 3) polycrystalline powders were synthesized by Pechini type solgel method. The changes in structure and electrical properties of B i 2S r 2C a C u 2O8+( abbrev. Bi2212) after Mn doping were investigated. Xray diffraction (XRD) and Fourier Transform Infrared (FT-IR) were employed to investigate the structural change of the samples. Conventional fourprobe method was used to study the electrical properties of samples. The results show that no secondphase diffraction peaks were detected except Bi2212 peaks. The lattice parameters of Bi2212 crystalline were changing with different Mn doping concentration. And the superconducting transition temperature of Bi2212 phase was decreased by about 11 K due to the Mn element introduction into Bi2212 lattice.
A nickelalactone with bisnitrogen ligand was synthesized from tmeda, Ni(COD)2and succinic anhydride. Then nickelalatone with bisphosphine ligand was synthesized through ligand exchange method. The impact of ligand on nikelalactone was tested. The synthesized products were characterized by 1H NMR, IR, Xray and 31P NMR. The results showed that the length of carbon chain in bidentate ligand had an effect on nickelalactone. Reactions of bisphosphines (where n=2) resulted in the formation of nickelalatone with bisphosphine ligand. While the homologous phosphines (where n=3,4) gave nickelalactones with didentate ligand.
The effect of initial concentration and pH value of the uranyl nitrate solution on the uranyl ion (UO2+2) hydrolysis reaction was studied by spectrophotometry. The maximum absorption wavelength of the obtained complexes in the reaction of UO2+2 ions with arsenazo (Ⅲ) at different pH values was also investigated. The results show that the absorption wavelength is 652 nm in the range of pH 3.0~7.0. It is easier for the uranyl nitrate solution to hydrolysis at higher pH value than the lower in the range of pH 4.0~6.0 at the same UO2+2 concentration. The uranyl solution at high concentration is prior to occurring hydrolysis reaction in the same pH value. Lowest pH values of various uranyl solutions were obtained for hydrolysis reaction. The results indicate that the concentration of uranyl solution should not exceed 1.000×10-3 mol/L at pH 5.0.
The H5PMo 1 0V2O4 0 with Keggin structure was prepared by mixing Na2HPO4, NaVO3, and Na2MoO4•2H2O in stoichiometric amount. Then the \[ Bm i m] 5PMo 1 0V2O4 0 hybrid materials was prepared by reacting H5PMo 1 0V2O4 0 with the 1butyl3methyl imidazolium bromide ionic liquid. The IR spectra and XRD data showed that the synthetic \[Bmim\]H5PMo 1 0V2O4 0 hybrid materials display Keggin structure. The SiO2supported \[Bmim\] 5PMo 1 0V2O4 0 hybrid materials were obtained, and the prepared samples were applied to the catalytic degradation of organic dyeRhodamine B. The optimal reaction condition was 30% of \[Bmim\] 5PMo 1 0V2O4 0/SiO2 loading, 1.5 mL of hydrogen peroxide, 0.2 g of the catalyst at 40 ℃. Under the optimal conditions, the highest degradation rate of organic dye Rhodamine B reached up to 97.58%. The catalyst show good regeneration performance, which can be reused at least four times and the degradation rate of Rhodamine B was no significant declined.
Because the risk factors for oil and gas transmission pipeline have complexity and fuzziness, and the factor weights are difficult to distribute. Therefore the entropy weight method was used to determine the factor weights, and the fuzzy comprehensive was used to evaluate the risk. First of all, the basic principle of entropy weight method and steps of fuzzy comprehensive evaluation method were briefly described. Then a section of oil conveying pipeline in Beijing area as an example, the risk evaluation index system was established and the factors weights were determined by using the entropy weight method. Finally, the risk level was determined by using the fuzzy comprehensive evaluation method, and the result was consistent with the judgment made by field experts. And according to the evaluation results, the corresponding prevention measures were proposed, so as to verify the feasibility of the method.
In order to operate the town polyethylene gas pipeline safely and reduce the operational risk, the possible accidents were analyzed that the town gas polyethylene pipe could occur and its reasons. Using fault tree analysis method, both the fault tree model and its sub fault tree model of the town polyethylene gas pipeline were established. Through the calculation of the minimum cut sets, the minimum path sets and the structure importance of it, the possible malfunctions of the town polyethylene gas pipeline and the reasons were analyzed. The research results show that the failure of town polyethylene gas pipeline had a larger threat, and the threat of pipeline auxiliary facilities failure was less. Among the reasons of pipeline failure, the influence of the outside interference was the largest|the scratches and defects of the pipeline had a minor influence|and the aging pipes and stress effect on the pipeline had the least influence on the pipeline accidents.
Coupling simulation was used in the buried seabed pipeline, to analyze the temperature field and stress field on the different leakage points. When the oil spilled to the sea mud area, it had the different influences on temperature field of the sea of mud, and there was a regular of distribution. When the leakage point was closed to the left and right sides of the pipe affected by gravity,the isotherm of leakage point moved down,the offside of leakage point moved up,the temperature field presented asymmetric distribution. When the leakage at the bottom of the pipes pressure field distribution was solely discussed, the isobar's distribution was symmetrical on both sides of the pipe, and gradually spread to the sides and top, and diffusion velocity had certain distinction with the leakage of buried pipe.
Wall building properties of highdensity drilling fluid weighted with manganese tetroxide and traditional weighting materials(barite, iron ore powder)in different proportion were studied. Experimental results show that highdensity drilling fluid weighted with the compound of manganese tetroxide and traditional weighting materials were synthesized in the optimum proportion, the effect of small size and spherical manganese tetroxide particles filled into large size barite or iron ore particles was more obviously than one single weighting materials. When highdensity drilling fluid was weighted with manganese tetroxide with barite and iron ore respectively according to the quality ratio of 1∶4 and 2∶3, filtration and permeability of cake was lower.
Since the 1990s, regenerative flue gas waste heat recovery unit of high temperature air combustion technology was used widely in the steel, iron, glass and molten aluminum industry. But the application on the vapor injection boiler in oil field was rarely reported. The principle of the regenerative combustion technology was introduced. Fuel efficiency, energy saving rate and steam production mass rate of the steam injection boiler were respectively calculated under the condition of the same fuel, furnace, furnace outlet smoke temperature using the conventional combustion technology and regenerative combustion technology. The results show that after applying the regenerative combustion technology, the boiler could not only save energy and improve fuel efficiency, but also improve the steam production mass rate. At the same time, it also could realize the use of lowergrade fuels. According to the characteristics of steam injection boiler, regenerative combustion technology could be completely applied to the steam injection boiler.
According to the domestic and foreign scholars on the research status of GFRP concrete column, the hollow reinforced concrete column confined by GFRP tube was put forward as a new type of member. Three hollow GFRP reinforced concrete columns were designed, and the compression capacity under three kinds of reinforcement ratio through the static test method was investigated. At the same time, the simulation analysis was carried out on the specimens combining with the finite element software ANSYS, a reference for practical engineering was provided. The results show the bearing capacity of specimen increased with the increase of reinforcement ratio, but not linear relationship. With the increase of reinforcement ratio, the confinement effect of composite columns increased firstly and then decreased. When the longitudinal reinforcement ratio of the new type of composite columns was 0.9%, the loading mechanism was best, and the confinement effect by the GFRP tube was largest.
Through the improvement of small excavator hydraulic system, by using AMESim software and establishing a simulation model of excavator boom hydraulic system, the influence of PID controller parameters on the system dynamic performance was analyzed. At the same time, its dynamic performance was simulated and analyzed. The results show that the global optimal solution of PID parameters improves the performance of excavator boom hydraulic system and obtains good effect, which offers references for the frequency response speed and stability of the system.
This experiment focuses on the fragile zone in Mu Us Desert where farming, forestry, animal husbandry interlacing ecologically in desertification research as the object. It studies the optimal computer automatic classification of Mu Us Desert based on CBERS and TM remote sensing image data type, and investigates the evolution process of Mu Us Desert (20002013) combined with the evolution of GIS spatial analysis and landscape index quantitative. The experiment shows that, through the maximum likelihood supervised classification method, the highest overall precision of sand type obtained is above 86.21%, which is the ideal means of desertification land classification. A nonlinear relationship exists between environment changes and shifting sands, semishifting sands, semifixed sands,fixed sands. Those four types of sand plaques present to be instability, in which shifting and semishifting sands change significantly in position, going on gradually from southwest to northwest and south. Succession between patches will still occur frequently in a period of time in the future, while the percentage of the four types of sands accounts from 82.29% to 75.07% of the study area, proving the ecological environment is getting better by the governance of Mu Us Desert.
his paper investigates the problem of robust H∞ reliable control for a class of discrete time uncertain switched systems with timevarying delays and actuator failures. Assuming that the H∞ reliable control cannot be implemented in each individual subsystem, based on the multiple Lyapunov function theory, a sufficient condition for the problem to be solvable is achieved under the strategy of switching state feedback, and the corresponding switching law and robust H∞ reliable switching controller are given. Finally, a simulation example illustrates the validity of the design method.
This paper discusses the hybrid mixed finite element method for elliptic interface problem in which the solution and gradient are discontinuous because of jump conditions across the interface. For the twodimensional elliptic interface problem, we propose the hybrid mixed finite element method on triangulation. The properties of this method mainly reflect in the following: the triangular mesh can nicely approximate the complex interface|they provide the approximations of all the variables, including the solution and gradient, with the optimal order|the matrix of final linear algebra systems is symmetric and positive definite, so it can be numerically solved by using for example conjugate gradient method. Numerical examples demonstrate the validity of hybrid mixed finite element method for elliptic interface problems.
At present, the majority of enterprises had to complete the task of energy conservation advocated by the government in energy audit in China. If things go on like this, the enterprises could not finish environmental guidelines, but be hindered to seek further development. Based on hotel industry data as sample, the relation between energy audit indicators and financial performance was researched. The results show that the enterprises using the energy audit, improved the enterprisesfinancial performance, prompted companies to consciously participate in energy audit, and improved their own core competitiveness.
With the development of our national economy, the scale of investment increased gradually at the business. The characteristics of the introduction of FDI scale of 19992013 in Liaoning province were summarized, to evaluate the carbon emissions from 1999 to 2013 in Liaoning province. Correlation between exploring the introduction of Liaoning province FDI scale and carbon emissions was studied, and the econometric methods was used. Through the ADF unit root test, cointegration test, the Grainger causality test, and generalized impulse response function method, the relationship between the identities of both was established, and a detailed analysis was made, the relevant reduction of Liaoning province carbon emission was put forward to propose according to the empirical conclusion.