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Thermal barrier coatings (TBCs) provide a good protection to high temperature corrosion of superalloy substrate in gas turbine. However, the lateral growth of the thermally grown oxide (TGO) and the thermal expansion misfit between underlying bond coat (BC) and TGO may induce internal stresses. In this work, the distortion occurring near a groove on a heat-resistant Fecralloy substrate was analyzed due to subjected to thermal and thermo-mechanical cycling. Experimental result shows that the distortion of the groove strongly effected by mechanical load.

Secondary water supply equipment was designed based on the current water supply source and municipal pipe network. The combination between Water purification and pressure-superposed water supply could guarantee the drinking water security, fully exploit the municipal pipe network pressure, and effectively save the energy. Catalytic oxidation of ozone, complex adsorption, and microbial degradation collaborated to treat the micro-polluted water. Activated alumina was employed for the high fluoride water purification with HCl/NaOH deep regeneration. For the brackish water, membrane treatment was adopted. A collaborative technology of ozone oxidation, contact oxidation, and biological oxidation was used for the iron/manganese-rich water. The results showed that all the effluents could meet the requirement of "Sanitary standard for drinking water" (GB5749-2006) and "Water quality standards for fine drinking water" (CJ94-2005).

Multiple 1090ES ADS-B signals may be overlapped in the receiver systems on the ground. At the same time, 1090ES ADS-B signals may be interfered by A/C replies with the same carrier frequency. To address these problems, firstly, principle component analysis (PCA) is employed to pre-whiten the observed signals in order to reduce the relevance between signals. Then extended projection algorithm (EPA) is applied to separate 1090ES ADS-B signals. Effect of the separated signal is verified by simulation. The performance of this algorithm is also analyzed in several aspects. Simulation results show that this algorithm not only can succeed in separating multiple 1090ES ADS-B signals effectively but also has both higher precision and strong ability of stability.

The gas turbine engines are used as the propulsion systems of the aircrafts, the vehicles or the power devices. Some components of the gas turbine engines are exposed to the high temperature environment. Therefore, durability of the components will directly affect the life cycles of the gas turbine engines. For protecting the blades of the gas turbine engines, a TBC (thermal barrier coating) system is used under the condition of combining with film cooling holes. The TBC systems can improve not only durability of the components in the high temperature environment but also the thermal efficiency of the gas turbine engines through increasing the operating temperature. In this paper, the simulation and optimization methods were studied for improving durability of the TBC systems. At first, the theoretical methods were discussed under the condition of considering the experimental data together. In the following step, the deformations near a hole under the different thermo-mechanical conditions were compared and optimized using DOE (design of experiments) method for the objective of improving durability of the TBC systems.

Data from the directional polarimetric camera (DPC) instrument onboard Chinese Gaofen-5 satellite dedicated to aerosol monitoring have been available recently. By measuring the spectral, angular and polarization properties of the radiance at the top of atmosphere (TOA), a DPC provides the aerosol optical depths (AODs) as well as partial microphysical aerosol properties. In order to evaluate the capability and the retrieval uncertainty of DPC sensor systematically, the information content and a posteriori error analysis are applied to the synthetic data of DPC multi-angle observation in this paper, which inherits from the optimal estimate theoretical framework. The forward simulation is conducted by the unified linearized vector radiative transfer model (UNL-VRTM), and the Jacobians of four Stokes elements with respect to aerosol and surface model parameters can be obtained simultaneously. Firstly, the error influences of surface parameter on the TOA measurements are simulated. The results indicate that a 10% relative error of parameter k1 in the improved BRDF model results in about 4.65% error of the TOA reflectance, while the error of TOA polarized reflectance caused by the same error of parameter C in BPDF model is negligibly small. Secondly, the multi-angle dependence of total information content in DPC measurements is investigated. It is shown that the information content increases significantly with the number of viewing angles, especially for the measurements of the first 9 angles. The DPC multi-angle observation can provide extra 5 degrees of freedom for signal (DFS) for the retrieval of aerosol and surface parameters, in which the retrieval of aerosol parameters is more sensitive to observation geometries than the retrieval of surface parameters in most cases. In addition, the total aerosol DFS increases with the range extension of scattering angle under the same number of viewing angles. After that, the DFS of each retrieved aerosol and surface parameter are given. For the aerosols, the volume concentration, real-part refractive index and effective radius show a high DFS (greater than 0.8). For the surfaces, the mean DFS of each parameter is greater than 0.5, which indicates the well capability of DPC in the surface retrieval. Finally, the a posteriori error of each aerosol, surface parameter and corresponding vary with the number of viewing angles, and the observation error and aerosol model error are discussed. The a posteriori error decrease significantly with the number of viewing angles, and the influence of the aerosol model error on the a posteriori error is not remarkable. In general, the observation error is the main influence factor on the uncertainty of the inversion results.

Raw micro-polluted water was sampled from a water treatment plant in Gaomi, a town in north China. The treatment with diatomite-enhanced coagulation was investigated, including the effect of dose and the dosing point of diatomite on enhanced coagulation. The results showed that the removal efficiencies of turbidity, color, UV254 and CODMn could reach 78.99 %, 76.19 %, 29.63 % and 22.77 %, respectively, when 15 mg/L diatomite was added at 30 minutes before coagulation. It was found that the optimum pH of diatomite-enhanced coagulation was approximately 6~7.

The objective of this research was to study the treatment effect of micro-polluted water usingconventional activated carbon filter(CACF) andaeration activated carbon filter(AACF), test the effect of backwashing on the performance of carbon filters, and provide a reference for water plant upgrading. The removal efficiency of pollutants and the impact of backwash of AACF was studied and compared with CACF. The results showed that, with an influent turbidity of 0.67 versus 0.44NTU, CODMnof 2.48 versus 2.74mg / L, UV254of 0.045versus 0.045cm-1and NH4+-N of 0.15 versus 0.11mg / L, the removal effect of turbidity, CODMn, UV254,and NH4+-N are 36.19% versus 33.67%, 30.63% versus 21.53%, 23.06% versus 26.57% and 34.34% versus 19.62% . AACF improved the treatment of CODMn,and NH4+-N by 26.66% and 60%. Backwash is found to enhance the performance of AACF on CODMnwith the removal efficiency increases from the 25.82% to 29.75% after 2 hr backwash, and stabilizes at approximately 30% at the consequent 6 hrs; Backwash decreases UV254removal from 17.51% to 16.64% after 2 hr backwash, increases it to 19.64% to after 4 hr treatment, and drops to 13.44% after 8 hrs. Additionally, backwash has no significant effect on NH4+-N.

Traditional wastewater treatment methods can no longer remove effectively nitrogen and phosphorus that are the direct murderers of water eutrophication hazard. Enhanced coagulation method was adopted to improve the treatment effect by dosing suitable coagulants and coagulant aids. The raw water was from the reclaimed water in a University. TP and ammonia nitrogen removal of the water had been researched through an enhanced coagulation process with dosing ferric chloride, aluminum sulfate, polymeric ferric chloride, and poly-aluminum chloride (PAC) in this study. The coagulants effects were estimated by determining the removal rate of ammonia nitrogen, TP, COD and turbidity. When dosing the raw water with 80 mg/L PAC, the removal rates of ammonia nitrogen, TP, COD and turbidity are respectively 6.12%, 67.79%, 26.21%, 85.41%. The experimental results can be used as a reference of water treatment in the reclaimed water station.

This work investigates the behavior of a hole on an alumina-forming alloy coupon subjected to thermal cyclic loading. The experiments, performed using a unique facility, revealed that a hole often deformed and cracked. To explain the phenomenon, the stress near a hole and the consequent deformation or cracking were analyzed and traced according to the loading cycles by theoretical approaches based on material properties of thermally grown oxide (TGO) and the substrate, including creep deformation, oxidation rate and growth strain, some of which were also measured by the facility, while others, such as the temperature-dependent material properties, were realistically assumed. The analytic solution for a two-dimensional model gave fairly good estimations of the mechanical behavior of the holes in comparison with the experimental observations, and the analytic solution was validated by numerical analysis for a three-dimensional model with TGO on the lateral surfaces. These results demonstrated that, without the cooling air flow, the subsequent thermal gradient or underlying bond-coated superalloy, deformation or cracking may occur near the cooling holes in turbine blades in gas turbine engines purely by thermal cycling, depending on the number of loading cycles.

To solve the problem of particle degeneracy in PF-TBD which can spoil the detecting and tracking performance of the algorithm, this paper applied the Particle Filter based on Particle Swarm Optimization (PSO-PF) into TBD. The algorithm use latest measuring information as the criterion to optimize the particles intellectively. By optimizing the particles intellectively, the particles redistributed towards the high likelihood ratio region and in this way the algorithm avoids the particle degeneracy problem effectively. Simulation result shows that compared with TBD based on generic particle filter, TBD based on the algorithm this paper proposed improved the detecting possibility and the tracking accuracy of target.

In strong clutter environment, the performance of traditional multi-target ‘track before detect’ (TBD) methods on target states and target number estimation descends badly. For this reason, this paper proposed a multi-target TBD method for pulse Doppler(PD) radar based on the Cardinalized probability hypothesis density (CPHD) theory. In this method, the TBD observation model for PD radar was built firstly. Secondly, the prediction equation and update equation of an augmented dimension CPHD filter based on both Doppler and amplitude measurements was deduced by Gaussian Mixture approximating in order to estimate the targets' states and number. The target states are updated sequentially using Doppler measurements after updating them using position measurements, then more accurate state and number estimation are obtained. Simulation results show that the proposed algorithm can suppress clutter and track multi-target effectively.

Location accuracy for low-altitude targets is not well in Short-Baseline system. A program of main station off-center of eight-station arrangement is proposed. Firstly analyses factors influencing the location accuracy for line-of-sight environments. Then researches the relationship between main station position and location performance, put forwards a location method of main station off-center of eight-station by increasing the base-station number and layout of the main station off-center which realizes multiple coverage of monitoring area using the redundant measurement information by main station off-center and more base stations provided. Finally gets the number of base station and optimal disposition way for low-altitude targets in the airport through simulating geometric dilution of precision (GDOP) distribution. Simulation figures and dates show that the main station off-center of eight-station arrangement can be achieved over 95% coverage of the airport for low-altitude targets location.

With the continuing phenomenon of eutrophication, the pollution of nitrogen has caused wide concern. Lack of organic carbon sources is always considered to be a key problem for nitrogen removal efficiency and cost when conventional biological nitrogen removal process was used to the treatment of ammonium-rich wastewater, but the anaerobic ammonium oxidation（ANAMMOX）can solve this problem .Anammox has so many advantages that it has good prospects in the biological nitrogen removal in wastewater. Anammox bacteria grows slowly, has a long generation time, and is susceptible to the environmental conditions. DO, Temperature, pH and organic can impact the process of anammox, so it is necessary to take careful methods to cultivate Anammox biomass. Depending on the purpose of improve water quality, appropriate treatment reactors and seed sludge should be selected to start ANAMMON process. The discovery of anaerobic ammonia oxidation, the reaction mechanism, influence application, the enrichment of anammox bacteria, physiological and biochemical characteristics of anammox bacteria, the start of anaerobic ammonia oxidation are reviewed in this paper.

A scheme was proposed to construct bilinear and quadratic Hamiltonians for frequency up-and down-conversions in cavity quantum electrodynamics(QED).Generally,in nonlinear optics,the interaction that the energe swaps between different optic modes without atomic transition is named frequency conversion.The proposed scheme was based on the interactions of a single four-level atom simultaneously with two classical driving fields and a two-mode cavity field,which is in the domain of four-wave mixing.By initially preparing the atom in a suitable state,each pump light was resonant with its transition,and two quantum modes were large tune to the other two transition,respectively,In the strong laser regime,the atomic degrees of freedom could be decoupled from the cavity degrees of freedom and the frequency conversion could be realized for the cavity modes.Due to the different initial states and interactions between optic fields and atom,frequency up-and down-conversions arose,respectively.After the preparation of squeezed operation respect to Frequency down-conversion,a discussion on the feasibility of experiment was given and the theoretical value was obtained.The advantage of this proposal is to realize the transition using two cascade photons,which is dipole-forbidden in a cascade structure atom,with high efficiency.The proposal will be useful for optical quantum control and fundamental tests of quantum theory.

In the hot section of a gas turbine, the turbine blades were protected from high temperature by providing a thermal barrier coating (TBC) as well as by cooling air flowing through internal passages within the blades. The cooling air then passed through discrete holes on the blade surface, creating a film of cooling air that further protects the surface from the hot mainstream flow. The holes are subjected to stresses resulting from the lateral growth of thermally grown oxide, the thermal expansion misfit between the constituent layers, and the centrifugal force due to high-speed revolution; these stresses often result in cracking. In this study, the deformation and cracks occurring near a hole on a heat-resistant alloy subjected to thermo-mechanical cycling were investigated. The experiment showed that cracks formed around the hole depending on the applied stress level and the number of cycles. These results could be explained by our analytic solution.

Thermal barrier coatings (TBCs) provide protection against high temperature corrosion of superalloy substrates in gas turbines. However, the lateral growth of the thermally-grown oxide (TGO) and the thermal expansion misfit between TGO and the underlying bond coat (BC) induce internal stresses which can be sufficient to activate plastic deformation or buckling in the TGO. The displacement instability of TBCs is affected by the TGO deformation. In this work, the deformation occurring near a groove on a heat-resistant alloy subjected to thermal or thermo-mechanical cycling was investigated. Experiments were performed with two different maximum temperatures and three mechanical load levels. The experiments showed that the deformation of the groove increased with maximum temperature. In addition, effects of load level, groove orientation, and the yttrium content in the substrate alloy on the deformation were determined.

Displacement instability along the interface between a zirconia top coat and thermally-grown oxide (TGO) forming metal substrate is a fundamental source of failure in some thermal barrier coatings (TBCs). In this work, the effects of material creep on displacement instability near the surface groove on Fecralloy substrate subjected to thermo-mechanical cycling are investigated using finite element analysis (FEA). Assumptions and references about material properties are minimized for a more realistic analysis. Most material properties, such as TGO growth and creep parameters, are based on in-house experimental measurements. Our results show that under a small magnitude of tensile stress, cyclic history plays a major role in displacement instability, and that this role significantly fades as stress increases. We also show that creep in the substrate material predominates at the holding time of a cycle. Creep significantly enhances the deformation near the groove without mechanical load applied on the specimen, while it contributes to length change rather than deformation of the groove as the load level increases.

Displacement instability of the thermally grown oxide (TGO) is a fundamental source of failure in thermal barrier systems. In this work, a finite element analysis has been performed to analyze the displacement instability occurring at a heat resistant metal with superficial TGO subjected to thermal cycling. Lateral and in-plane growth of the TGO which happens during high temperature is simulated by means of material property change from the substrate metal to the TGO. Most of the material properties including the TGO growth are based on the results experimentally obtained in-house. Results of the finite element analyses agree well with the experimental observation, which proves the accuracy and validity of this simulation. The technique will be useful for future work on more complicated phenomena such as deformation under thermo-mechanical cycling.

We give a detailed description about the reflected spectrum of a few-cycle pulse propagating through a resonant dense medium. An unexpected low-frequency spike appeared in the red edge of the spectrum. To figure out the origin of this redshift spike, we analysis the mechanisms responsible for the redshift of the reflected field. So far, the redshift has not been well studied for few-cycle pulses except a brief explanation made by the previous study [Kaloshan et al., Phys. Rev. Lett. 83 544 (1999).], which attributed the origin of the redshift to the so-called intrapulse four-wave mixing. However, we demonstrate numerically that the redshift consists of two separated spikes is actually produced by the Doppler effect of backpropagation waves, which is an analogue effect of dynamic nonlinear optical skin effect. Our study elucidates the underlying physics of the dynamic nonlinear optical effects responsible for the redshift spikes. Moreover, the dependency of the their frequency on the laser and medium parameters, such as medium density and input pulse area are also discussed.