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M2SiO4: Tb3+, Mn2+, Nd3+ (M = Mg2+, Ca2+, Sr2+, and Ba2+) phosphors suitable for near-ultraviolet-violet radiation excitation were successfully prepared at 1400 °C in N2 atmosphere by a high-temperature solid-state reaction, and their phase compositions and luminescent performance were also studied by X-ray diffraction (XRD), photoluminescence spectra. Results show that their emission intensity increases in the order of Ca2SiO4 > Mg2SiO4 > Sr2SiO4 > Ba2SiO4 matrix phosphor. Ca1.94SiO4: 0.02Tb3 +, 0.02Mn2+, 0.02Nd2+ phosphor exhibits the best luminescence performance.

A hydrothermal process was proposed to prepare BiVO4/ diatomite composite photocatalysts, where BiVO4 was grown from a precursor solution containing diatomite, and EDTA used as a chelating agent to prevent the precipitation of precursor solution compositions on diatomite before hydrothermal treatment. The effect of some processing parameters like diatomite percentage and Ag-loaded amount on their photocatalytic performance were also investigated in detail by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), BET, and UV‐Vis spectroscopy. The results show that BiVO4/ diatomite composite photocatalysts can be successfully prepared at 160 °C for the duration of 3h by the hydrothermal process. The diatomite has two significant impacts on their photocatalytic performance: (1) enhancing the dispersion of BiVO4 crystallites due to its high porosity and specific surface area to favor their photocatalytic performance, and (2) having a light screening effect to incident visible light to decrease their photocatalytic activity. Appropriately incorporating diatomite could improve their photocatalytic performance, but the overuse of diatomite would reduce that. Similarly, depositing Ag could effectively improve their photocatalytic activity because of its good light absorption and photosensitive characteristics, but excessive addition would result in their decrease since the overuse of Ag would also promote the electron-hole recombination.

A microstructure consisted of granular bainite, upper bainite, acicular ferrite, polygonal ferrite, and a little of pearlite was obtained by controlling rolling and cooling in marine steel. The grain size of the two steels was refined to 5-9 μm. The size of the MA island was about 3-6 μm. Both steels had higher tensile strength, yield strength, elongation and hardness, and the performance of steel B was better than that of steel A. Both steels exhibited large and deep dimples at -80 °C impact fracture. The longitudinal impact energy of the specimens was above 250J, and the steel B even exceeded 300J. Its longitudinal impact performance was better than lateral impact performance. Both steels had achieved good performance due to fine grain strengthening, MA island strengthening, precipitation strengthening and dislocation strengthening caused by controlled rolling and cooling. The alloying element nickel effectively improved the low temperature impact toughness of the experimental steel. Excellent impact energy of both steels was attributed to higher texture strength for RD specimens.

In metastable beta Ti alloys, microstructural features can be varied over a wide range of length scales by changing different heat treatment parameters. Effect of cooling methods on microstructure and mechanical properties of Ti-3537 alloy after solution treatment was investigated. The result shows that with the decrease of cooling rate, the Vickers hardness of the alloy gradually increases. Among the three cooling methods of OQ, AC and FC, Ti-3573 alloy has the best shape and moderate yield strength, but tensile strength. The fractography of the β-substrate specimens showed that the fracture mode was ductile fracture. In the FC state, the α phase precipitates in a large amount in the Ti-3573 alloy, the yield strength and the tensile strength are greatly increased and the elongation is remarkably lowered. The tensile fracture shows a shallow fracture dip with low toughness.

In this regard, two beta titanium alloys in the Ti-Al-Mo-V-Cr system, Ti-3Al-5Mo-7V-3Cr (Ti-3573) and Ti-3Al-8Mo-7V-3Cr (Ti-3873), have been designed. Comparison of the microstructure and mechanical properties of both alloys after solution treatment was conducted. The result shows that the β grains in Ti-3873 alloy are abnormally grown at WQ. The elongation of Ti-3573 alloy is higher than that of Ti-3873 alloy, it is related to the the smaller grain size. The Ti-3873 alloy has moderate plasticity but higher yield strength and tensile strength. Fine and deep dimples associated with ductile fracture were obtained for the Ti-3573 alloy. The fractography of the β-substrate specimens showed that the fracture mode was ductile fracture. The Ti-3873 alloy has a combination of slip and twinning during deformation. It is possible for the Ti-3573 alloy to undergo both twinning and TRIP effect upon deformation. Therefore, Ti-3573 alloy exhibited good plasticity and strength matching.

Different cold rolling reductions were adopted for commercially pure titanium sheet. Cold forming properties were investigated by a microstructural analysis, Vickers microhardness and erichsen value measurements. The results have shown that Cold rolling resulted in refined alpha grains. Alpha grain size was refined further by greater cold reduction. Alpha grain sizes of the specimens of processing 1, 2 and 3 reached 30.90 μm, 26.48 μm and 20.58 μm, respectively. Cold forming properties were affected by different alpha grain sizes. The hardness and erichsen value reached the lowest and the highest values for the specimens in processing 1. The hardness increased and erichsen value decreased due to the finer alpha grain size for the specimen which was cold-rolled at a reduction of 50% in processing 2. Erichsen test results of the specimens of processing 3 had the lowest values due to the deformation of a reduction of 70%. Cold forming properties of the specimens of processing 3 were deteriorated, this is because deformation leads to the high dislocation density and the stored energy increases with accumulated strain after deformation.

Atmospheric corrosion test of TRIP steels was conducted in laboratory. The surface morphologies of the specimens were analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD) and electro-probe microanalysis (EPMA). Corrosion performance of TRIP steels under atmospheric environment was investigated by discussing the protective mechanism. The corrosion rates of steel A are significantly greater than steel B in atmospheric environment tests. The enhancement of corrosion performance of TRIP steel is attributed to the additions of alloying elements, such as P, Cr, Cu, and Ni etc.. The alloying elements increase the compactness and densification of rust layers. Electrochemical characteristic of TRIP steel is improved by means of the enhancement of the thermodynamic stability.

The LMD is a new method for analyzing non-stationary signals. It can decompose complicated signals into a set of single-component signals, each of which has physical sense. But peforming the LMD will produce end effects which make results distortion. After analyzing the reasons for these, the ariticle takes adcantage of three normal methods to overcome the end effects of LMD. Experimental results of three models showed that the method of self-adaptive waveform matching was better than other methods.

The surrogate model has been extensively applied in engineering optimization design recently. Based on surrogate model, the complicated functional relationships between variables and responses can be precisely described. In this paper, the Kriging surrogate model are adopted to simulate the relationships between the sound pressure level (SPL) peaks at the drivers right ear (DRE) and the performance parameters of excavator cab shock absorbers with the FEM model, followed by the optimization design been accomplished with algorithm NSGA-II. The results indicate that the SPL peaks and the overall SPL can both be decreased through optimizing the performance parameters with Kriging surrogate model.

As 2# and 3# coal in Baoxin coal mine are close distance coal seams, combined mining is adopted to ensure the production, and reasonable staggered distance needs to be determined between the upper and lower adjacent workfaces. Calculated on the influence of strata movement, there is a empirical formula for the coal’s alternate distance.It is necessary to analyze the factors in the formula

The cab acoustic response, which could be considered to be random and stationary, determines the riding comfort of the excavator. In order to get the most useful information from the actual cab noise signal, an acquisition method of typical time course for a stationary signal was proposed in this paper. Firstly, a series of de-noising preprocessing was applied on the test signal. Then, the stationarity and ergodicity of that were examined via runs test method. Finally, combining with FFT, IFFT and the frequency weighting, the typical time course was obtained. The results show that the statistical parameters and spectral characteristics of the obtained typical time course are consistent with those of the measured signal, which means that the obtained one could be regarded as a representation of the actual signal for further analyzing more effectively.

Considering the discontinuities of the phase saturations and pressure gradients at the matrix-fracture interface, a modified algorithm for the embedded discrete fracture model is proposed. In this algorithm, the exchange rate between fracture and matrix on two sides of the interface are calculated separately. To avoid the problem for defining the physical variables on the matrix grid blocks overlaid by fracture, the Neumann boundary conditions are instead in the calculations of other matrix grid blocks. The numerical examples show that the simulation results of the proposed algorithm agree very well with those of the discrete fracture model. In reservoir with high matrix capillary pressure, the grids must be enough refined in the neighborhood of the matrix-fracture interface to achieve high numerical accuracy.

The mechanism governing activated sludge flocculation under Al3+ dosing was studied in this paper. Activated sludge was cultivated in sequencing batch reactors (SBR) at 22°C. Batch dosages of Al3+ were 0.00, 0.125, 0.5, 1 and 1.5meq/L respectively, and continuous dosage was 0.1meq/L. As batch dosage increased, the total interaction energy, zeta potential and turbidity tended to decline, which suggested that batch dosing promoted sludge flocculation. Under the equivalent dose, the zeta potential of continuous dosing was higher, while the LB-EPS content showed the opposite tendency and turbidity reduction was similar. Both batch and continuous dosing promoted flocculation performance: in terms of interaction energy, batch dosing was more effective; while in terms of EPS, it was on the contrary.

This paper converts DEM data to 3D terrain by using Direct3D technology, then, creates landslide on the 3D terrain ,and simulates landslides and mud-rock flows during the whole process in time by using Smoothed Particle Hydrodynamics methods. The landslide is abstracted to particle swarm of Direct3D in this simulation, each particle movements in the gravity, pressure and viscous force between particles and other physical forces so that implements three-dimensional and dynamic simulation of landslides and mud-rock flows. The extent of landslides and mud-rock effects is reached by estimating the real time location of particles, thus we can make early warning of the extent of landslides and mud-rock effects and provide technical support for disaster prevention and mitigation work..

Abrasive belt grinding experiments of ZrO2Engineering Ceramics are carried out by using 4 different abrasive belts. The orthogonal test with zirconia-corundum belt was to get the best grinding parameter, the amount of material removal workpiece surface roughness and belt wear were measured to get the best grinding parameter.In this paper,the influence of abrasive belt granularity and different grinding parameters to grinding efficiency and workpiece surface quality throughout the process of grinding ZrO2Engineering Ceramics was analyzed. Analysis wear mechanism of engineering ceramics based on the Abrasive cutting model by observing the surface morphology. The results show that increasing the grinding force or the abrasive belt granularity can decrease the workpiece surface roughness;With the abrasive belt speed or grinding force increasing,the material removal rate and the wear ratio to some extent, but brittle fracture is occued easily on its surface when exceeds the critical value; When the abrasive belt speed is 19m/s,the grinding force is 15N and the abrasive belt granularity is 120#, ZrO2Engineering Ceramics grinding effects reach the best.

A series of tests for low cycle fatigue were conducted on the tubular specimens for 304 stainless steel under variable amplitude and irregular axial-torsional loading. Rainflow cycle counting and linear damage rule are used to calculate fatigue damage and four approaches, e.g. SWT(Smith-Watson-Topper), KBM(Kandil-Brown-Miller), FS(Fatemi-Socie), and LKN(Lee-Kim-Nam) approach are employed to predict the fatigue life. The maximum shear strain plane, the maximum normal strain plane, and the maximum damage plane are considered as the critical plane, respectively. The effects of the choice of the critical plane on previous approaches are discussed. It is shown that comparing with the maximum shear/normal strain approach, the predictions are improved by using the maximum damage plane approach, part nonproportional paths for SWT, AV and part nonproportional paths for KBM, TV paths for FS. But for LKN, the prediction results are nonconservative for some paths than that of the maximum shear/normal strain approach.

This paper introduces the service-oriented architecture technology, and proposes the architecture model of Out-trajectory Data Processing in distributed environment. According to the demand and features of Ship-borne Out-trajectory Data Processing flow, it describes how to carry out cross-platform service integration by using the Service Bus Middleware, and provides a kind of typical distributed deployment strategy.

Computer vision based mechanical parts recognition has been received much research attention in recent years. In this paper, we present a new framework to address this problem. The framework utilizes the computer graphic technology to model mechanical parts. Recognition is realized by comparing one query image to the instance images using improved affine transformation based on particle swarm optimization (PSO). Our experiment shows that the proposed framework outperforms the conventional invariant moments based recognition methods in recognition rates.

In order to construct a simply structured alcolock device for autocar steering safety, the plunger solenoid with the conical face pole form is utilized to fabricate a electromagnetic actuating unit with double plunger solenoids. The unit can generate a electromagnetic actuation with long travel to complete the coverage of auto start-up lock hole and hence to stop the vehicle launch; the magnetic actuation is controlled by using a alcohol sensing system, and the shutting function for starting-up lock hole is generated by a baffle installed at the top of plunger solenoids as the actuating control is started up on the basis of an alcohol sensing signal. The plunger solenoid with conical face pole form possesses the output characteristic of long stroke and steady stroke force.

Seepage control is one of the important problems when designing a hydropower station. The upper reservoir of one hydropower station was built by excavation and backfill partly. Its impermeable program is the combination by concrete panel, geomembrane and vertical curtain. With the finite element method , the model of the dam has been built. The potential distribution of groundwater in the library on the seepage filed is analyzed. It also analyzes the seepage slope of dam body, dam foundation and reservoir and calculates the seepage discharge and replenishment at the situation of normal storage level. The results show that potential distribution law of reservoir seepage field is clear and definite. The effect of cutting water head by anti-seepage curtain and curtain downstream under protective layer at the bottom of the coarse sand and back packing drainage is remarkable. The panel and geomembrane have an effect on cutting waterhead. The seepage flow of upper reservoir is 488.16m3/d and the supply flow is 1019.52m3/d. So the control scheme of the upstream seepage is reasonable technically.

With the development of national economy, space structures of great spans develop quickly. The architectural modelings update, structural systems diversify and structural spans gradually expand. So the study on space truss structure under different specific conditions has great significance upon the security, the proper use and reducing cost.

Exoatmospheric IR detector is an effective means of space debris detection. In order to achieve the goal of an effective detection for low-orbit space debris, study the detection range for exoatmospheric IR detector. Studied the infrared detection technology, as well as the specific characteristics of the low-orbit space debris and other related aspects. First of all, introduce the method of detection process and determine the characteristic parameters of the space debris and infrared detectors. Then, calculate the space debris’ own infrared radiation energy and the background radiation energy. Then, by the infrared detector receives the photon number, refer to the engineering practice, the detecting range for exoatmospheric IR detector enhanced in evidence. The ground-based experiment demonstrates the calculation is preciseness and credibility. The space debris’ orbital height is 550KM and its size is 8m × 1.2m × 0.025m. Under such conditions, the detecting range for exoatmospheric IR detector is 48KM .This method can provide a certain referential significance for pace debris detection, imaging, and attacks.

Based on fractional Fourier transformation (FRFT), the feature of the signals which vary smoothly from time domain to frequency domain is given. The FRFT method is applied to the estimation and detection of nonlinear frequency modulated signals to which piecewise linearly approach. Wigner-Ville time frequency distribution of the signals is used after approaching and the masking results of the original signal accumulate energy as detecting statistic. A signal detector based on energy accumulation from time frequency domain in the angle of analysis of both time and frequency is proposed. Finally, a comparison with traditional non-coherent energy accumulation methods is made, which shows the proposed method has superior performance.

The removal of geosmin by powered activated carbon (PAC) was studied at laboratory to select suitable PAC type and the removal efficiencies of geosmin by PAC in different application point as an emergency method were evaluated. The adsorption efficiency of coal-based PAC on geosmin was superior to that of bamboo-based PAC. The contact time and PAC dose were two important factors that affect the removal effect of geosmin. Geosmin could be controled below 10ng/L at 200ng/L of initial concentration.

Taking the raw water of Yangtze Chenhang Reservoir as the research object, the characterization of diatomaceous earth, and the removal efficiency of CODMn, turbidity by precoat filtration process were investigated by pilot experiment in this paper. The results showed that diatomaceous earth patterns having porous structure and the pure silica peak at 2θ angles 21.980, 36.080, 31.460 and 28.430 in XRD analysis. Precoat filtration has a good stability to remove solid suspended particle, effluent turbidity was remained about 0.05NTU. Precoat filtration had no effect on removing CODMn. The pressure of 50KPa could be defined as a critical point in this experiment. Beyond the critical point, the devices should be stop and backwash, to resume operation pressure. Overall, precoat filtration can be defined as a filtration technique for relatively low turbidity raw waters.

Red clay belongs to region special soil.It has engineering geological properties that are different from general soils.The natural red clay has high ratio void ratio,high moisturecontent,low density and so on.But red clay has non-corresponding high strength,bearing capacity of foundation and low compressibility. With the high speed development of China economy,the main soil named red clay in South is used as bearing stratum of many building foundations.However,when red clay is used as foundation,it is regarded as gerenal clay to consider its bearing capacity of foundation.So this will cause two disadvantages.First,potential is not given full play,resulting in considerable waste.Second,red clay has some special properties,such as high woid ratio,softening in water.These properties will bring hidden troubles,causing some bad accidents.These are caused by lacking of knowledge to engineering properties.Xiamen locates in southeast of China,and red clay is widely distributed.It is formed by accumulation through laterization of granites and basalts.So it is essential to study red clay.In this article,literatures of red clay in Xiamen are collected.Indoor conventional geotechnical tests are done,some engineering property parameters are obtained.

This topic mainly research the high back pressure heat supply technology of steam turbine generator unit and the correlation analysis of turbine under high back pressure operating condition. High back pressure heat supply is an energy saving technology developed in order to meet the requirements of energy saving and environmental protection. This technology can not only reduce the cold end losses to improve the thermal efficiency of power plant, but also decrease the energy loss and pollution emissions because it take the place of traditional heating boiler. High back pressure heat supply of steam turbine is to increase the quantity of air inlet and outlet as well as exhaust temperature through improving turbine back pressure. For condensing steam turbine unit of 50 MW studied in this article, back pressure of which rise to 0.032MPa from 0.0046MPa, and the exhaust temperature will increase to 70 °C respectively. Through the calculation of rated condition and variable condition, we can obtain the impact to the unit due to the change of back pressure, and for unit of 50 MW can reduce 30876.9 tons of standard coal consumption in a heating period. It can also decrease the emission of carbon dioxide, sulfur dioxide, smoke and ashes, which effect of energy saving and emission reducing is very obvious.

According to the data on the geology, geochemistry, experimental analysis and production test of Liaohe Depression, the reservoir forming conditions of shale gas and oil were analyzed in this study. It is found that the Paleogene shale in the sedimentary basin has an extensive distribution, large thickness, high organic carbon content and wide variation scope of maturity of organic matter. It provides the material conditions for the formation of shale gas and oil. The shales have developed micropores and fractures, which provide favorable reservoir space for the free hydrocarbons. Due to the strong adsorption ability of shale, the gas logging abnormal of total hydrocarbons is usually present in the shale. A huge reserve of shale gas and oil resources is indicated. The shale reservoir usually has a high content of brittle minerals, so the fracturing technique can be applied for development. Therefore, the Paleogene strata in Liaohe Depression contain abundant shale gas and oil and the associated tight gas and oil resources. The shale gas and oil in the hydrocarbon generation sag and the surrounding shales and the interbed are the new deposits under the deep exploitation of Liaohe Depression. The shale gas and oil in the West Sag has the highest potential.

F, the most electronegative element, is easy to catch the electrons in the bonds to form the stabilized C-F. Perfluorinated acids have high chemical stability which can tolerate acid, alkali, etc. Inhibition effect was observed in the complex pollution system in which 7 kinds of perfluorinated acids existed simultaneously. The formation of hydrated electrons was the rate-limiting step in complex pollution system, and the inhibition was increased as the carbon chain increasing. Compared the reduction rate of perfluorinated acids by photo-induced hydrated electrons in the complex pollution system with the single rate, the results showed that there were positive linear correlations between the degradation rate and photo-induced hydrated electrons. The degradation multiples of perfluorinated acids were studied, it concluded that, because of the competition among the 7 kinds of perfluorinated acids, the degradation rates were influenced.

The diversity and abundance of ammonia-oxidizing bacteria was investigated in three different types of horizontal subsurface flow constructed wetlands, reed (Phragmites australis)/gravel bed (W1), hybrid vegetation {reed, cattail (Typha latifolia), bulrush (Scirpus validus)}/gravel bed (W2) and reed/hybrid substrates bed (gravel, zeolite, slag) (W3). The investigation of community structures of ammonia-oxidizing bacteria revealed that the types of macrophytes , substrate and space distributions had significant influence on the microbial community. The ammonia-oxidizing bacteria detected were all inculturable, and belonged to Nitrosomonas spp.

In view of the difficulty in giving a quantitative description of the degree of uneven distribution of water resources, this paper, based on a cloud model, explores the temporal and spatial distribution characteristics of water resources in some research areas in Guangdong Province by using quantitative methods. The results show that, firstly, cloud images of a cloud model make it possible to describe intuitively the characteristics of the temporal and spatial distribution of water resources and present the differences of these characteristics in different areas through numerical characteristic values. Secondly, there are the least amounts of water resources in western Guangdong and the most in the Pearl River Delta Area. Temporal allocation of water resources is difficult in the northern and eastern parts of this province while spatial allocation difficult in the eastern and western parts. Thirdly, there are more water resources, less non-uniformity in the temporal distribution, greater stability in terms of temporal and spatial distribution but greater non-uniformity in the spatial distribution of water resources in the downstream than upstream of the Pearl River in Guangdong Province. Fourthly, there is less non-uniformity in the spatial distribution than in the temporal distribution in northern Guangdong while stability of spatial distribution is worse than that of the temporal distribution in western Guangdong. In addition, there is less uniformity but greater stability in the spatial distribution than in the temporal distribution of water resources in each research area.

Azo compounds constitute the largest and the most diverse group of synthetic dyes and are widely used. The release of coloured wastewaters represents a serious environmental problem and a public health concern. The aim of this study was to investigate the impact of sulfate and redox mediator on the reduction of an azo dye (Acid orange 7, AO7) by anaerobic sludge. The kinetics showed the AO7 reduction rate can be greatly improved by the addition of sulfate and RF, thus it is possible to speed up the start-up of AO7 reduction system under appropriate condition.

The removal of ammonia nitrogen from the polluted water was investigated in three different types of horizontal subsurface flow constructed wetlands, reed (Phragmites australis)/gravel bed (W1), hybrid vegetation {reed, cattail (Typha latifolia), bulrush (Scirpus validus)}/gravel bed (W2) and reed/hybrid substrates (gravel, zeolite, slag) bed (W3). At HRT of 28 d, NH3-N removal efficiencies of W1, W2 and W3 were-130%98%, -120%98% and 21%98% respectively throughout the whole year. The results showed that zeolite and slag contributed to higher NH3-N removal than gravel, especially in winter, and that cattail and bulrush did not show significant influences on NH3-N removal. The ranges of NH3-N removal rates were-2.332.14, -2.272.33 and 0.082.52 g·m-3·d-1 respectively under HRT of 2 d. NH3-N removal rates of W1 and W2 were much more affected by temperature than that of W3, which was due to the adsorption/desorption of zeolite.

Acceleration signals at the mounts of an excavator cab are collected and analyzed, on the basis of which causes of peak values in the sound pressure level (SPL) at the drivers right ear (DRE) are discussed. A damping material layer made up of chlorobutyl rubber is arranged to the cabs panels by simulations according to results of panel acoustical contribution analysis, which indicates a great decline of the SPL peak values.

Denitrification is strongly dependent on carbon quantity and quality in most constructed wetlands (CWs), and pH may be a key factor in determining the supply of available carbon source (ACS) in the pre-treatment of external plant biomass. In this study, three bath CWs were designed, and were fed with nitrate-dominated water to investigate nitrate removal affected by external cattail litter with different pH pre-treatment (pH = 7.0, 10.0, 12.0). During the experiment, higher nitrate removal was observed in the wetland using pH12.0 pre-treatment litter leachate as the carbon source. Strong alkaline fermentation at ambient temperature can be considered as a sustainable technology for wetland plant litter pre-treatment.

This study investigated operational performance and microbial communities in the integrated acidification-denitrification bioreactor and the followed methanogenesis process. Industrial wastewater, cassava stillage (CS) was used as the carbon source amended with or without nitrate. The results showed that acidification and denitrification could occur simultaneously in a single acidification-denitrification reactor, and denitrificatoin did not suppress the acidogenic activity. Both denitrification and DNRA could contribute to nitrate reduction and proportions of them were about 60% and 40% respectively at the tested condition of COD/NO3-Nof 50. The introduction of nitrate into acidogenic phase did not have any effect on the followed methanogenic process. Microbial communities sampled from two systems were analyzed by culture-independent techniques based on PCR-DGGE. The relative abundance of acid-producing bacteria (primarily Parabacteroides distasonis and Chloroflexi) in the nitrate-amended reactor further confirmed that the addition of nitrate did not suppress the activity of acid-producing bacteria. Bacteria involved in denitrification and DNRA were also detected. The archaeal communities in methanogenic reactors of two systems showed no significant differences. And Methanoculleus and Methanolobus were the dominant bacteria in the culture.

In view of the reciprocating flow of the tidal reaches in estuarine areas and uneven horizontal distribution in the process of pollutants transferring, this thesis proposes a calculation method for the water environmental capacity on the basis of reciprocating flow model and uneven coefficient method. Taking North Channel, downstream of the Min River, as an example, a two-dimensional unstable-state model of water flow-quality is established. According to its hydrologic features and the date measured, flow field and concentration field of this river section are simulated, and meanwhile, response relation curve of the discharge capacity of those general pollutant sources in relation to length of pollution zones, at moments of maximum flood tide and maximum tide ebb, is built. Besides, North Channel is divided into two studied sections whose uneven distribution coefficients at the above mentioned two moments are calculated respectively. Considering the reliability, uneven coefficients at floodtide and tide ebb are replaced by those at the moment of maximum flood tide and maximum tide ebb, and the uneven coefficient method is adopted, on the basis of reciprocating flow model, to calculate the water environmental capacity of North Channel. The findings show that, by adopting the two-dimensional unstable-state model of water flow-quality, values of both the flow field and concentration field in this river section thus calculated, are approximate to the values measured. Chooses 90% confidence surface flow and take neap as sample, the water environmental capacity of CODMn in North Channel is 16716.8t/a.This method, together with the reciprocating flow model and uneven coefficient method, reflects the influence of reciprocating flow and complex pollution migration and diffusion, under the tidal action, on the water environmental capacity of tidal reaches in estuarine areas.

Simulation models of resistance mufflers with different typical structures were established, through the computational fluid dynamics method, under the conditions of different inlet velocities, by analyzing distribution characteristic of velocity field and pressure field for flows internal the mufflers, a kind of mathematical relation among the inlet velocity, inlet/outlet pressure, and pressure loss was discovered. Through CFD simulation computation and practical measuring tests of above three parameters for practical muffler with complex configurations, the mathematical relation of them was proved to be correct. With the conclusion, while inlet velocity changed, the variable conditions of inlet/outlet pressure and pressure loss for resistance mufflers could be estimated approximately Therefore, the test expense could be saved, and the designing efficiency for mufflers could also be further improved, so it would bring a certain economic benefit,which would be of great significance for energy saving research of mufflers.

The concept of Space Resources On-Orbit Repurposing (SROOR) is generalized by presenting the brief introduction of Phoenix Program. The feasibility of satellite bus components repurposing is analyzed, as well as the resources in geosynchronous orbit (GEO). Several safety dynamic requirements are studied and simulated. The conclusion suggests that SROOR is not only feasible but also needful and has broad application prospects.

Product color design is a powerful tool for establishing brand image. This paper analyzed the development status of construction machinery industry, and on the basis of that presented the necessity of establishing brand image through product color design in the construction machinery industry. Then after analyzing the special environment and people-related elements to be considered when designing construction equipment, and combined with successful brand image construction cases, proposed three principles for the product color design of construction machinery products.

The volatile fatty acids (VFAs) are kinds of effective external carbon source for enhanced biological nutrients removal. Volatile fatty acids (VFAs) production from anaerobic fermentation from cassava stillage (CS) wastewater, starch wastewater (SW) and the yellow wine wastewater (YWW) was conducted in batch tests. The VFAs production potential and the characteristics of the fermentative liquid were compared and discussed. Experimental results indicated that the cassava stillage wastewater and the starch wastewater were preferable feed for anaerobic VFAs fermentation. Acetic acid, propionic acid and butyric acid were the main components of the VFAs with respective percentage of 36.5%, 20% and 40% at the end of its fermentation.

To study directional pressure relief blasting, cement mortar model tests are carried out. Protecting borehole wall, free-face wall and bottom wall are tested of the dynamic strain. Three-dimensional numerical simulation and numerical calculation of the tests are conducted by using LS-DYNA3D. The pressure values and test results of the protecting borehole wall, free-face wall and bottom wall with the same distance from the explosives are compared. Development and distribution of pressure regularity are analyzed; blast hole pressure relief effect of protecting borehole wall materials and bottom interval air column are explicated. The present results indicate that there is an obvious stress concentration phenomenon on the free-face wall, with an average pressure decrease rate of 26% from the free-face wall to the protecting borehole wall with the same distance to the explosive center, while the isolation materialPVCU plays a good directional protection. The pressure effect of the blast hole bottom air column on the blast hole is apparent. The simulation results are consistent with the experimental dates.

With the trend of modernized management, the line loss management is becoming more and more professional and particularized. But, due to large potential economic interests in distribution network, some line loss management personnel are lured by economics interests and not easy to keep clean and honest. In the power system, one is to make the line loss index called the manager, the other is to check the actual line loss called the executor. Due to superior technical and management weakness in the line loss management, there exists prevailing information asymmetry between the managers and the executors. Therefore, some economic crime on some critical posts will arise, and this will harm public interest. So, it is critical to balance the interest distribution between the managers and the executors based on the line loss management in distribution network. The article created the differential equation model by taking advantage of ecological niches theory to research the game between the managers and the executors in the interest chain of the distribution network. By analyzing, the model has proved the reliability of the interest balance between the players in the line loss management. And then, a simulation model were given out. The conclusions are contributed to the line loss managerial department.

This paper deals with the design, simulation and implementation of a digital sliding mode controller for brushless DC motor-based electromechanical actuator. Firstly, a mathematic model of the actuator is drawn from its structure. Secondly, sliding mode control algorithm with the approach to weaken chattering is designed for the system, and simulations are carried out under Matlab/Simulink environment. Thirdly, the SMC algorithm is implemented on TMS320F2812 digital signal processor platform along with extensive experiments. Lastly, results of simulation and experiment are compared and discussed, showing that the proposed approach can achieve accurate and fast position tracking in the presence of load disturbance and plant parameter variations.

Collect a hydraulic excavators radiated noise ten meters away under set conditions, and also the relevant noises near the excavator. Analyze noise signals with wavelet packet to get the main band of energy distribution. Then calculate the two signals correlation coefficient, which identifies the muffler exhaust noise and inlet noise as the main source for right rear radiated noise.

This paper researched the post management on line loss management in power system. As while, This article studied the characters of the line loss management in power system depend on the practical experiences. it would pose a new problem to address the regulatory lacunae revealed by post management department. Meanwhile, The article established a optimal model to restrict the working time of the manager which is so-called post rotation cycle. And then, the paper gave out the further discussion about the model, and the model proved to be reliable and practical. It is of great value to probe into how to efficiently utilize management resources to improve corporation management ability and level and achieve the advanced goals.

Discovered in recent years, Chang 4+5 reservoir group of Yanchang Formation in Jiyuan area is ultra-low permeability reservoir. The evaluation and prediction of the reservoir is the most critical technology in reservoir development. Comprehensive analysis with multiple research approaches shows that the storage potential of the ultra-low permeability reservoir is jointly controlled by sedimentation and diagenesis. Sedimentary factor includes lithology and sedimentary facies, two basic factors affecting the storage potential. The reservoir lithology is of fine-grained debris-arkose and miliary arkose. Pore types are mainly intergranular pores and dissolved pores. The sandstone microfacies in the delta front underwater distributary channel has the best storage potential. Diagenetic factors, including diagenesis types, evolution, intensity, combination etc., have direct influence on the reservoir storage potential. Compaction and calcite cementation are the main factors that weaken the storage potential, whereas carbonate dissolution, especially the dissolution of feldspar plays an important role in the improvement of the storage potential.

Qinhuangdao City combines three traditional coastal zone resources, namely, harbor, tourism and fishery. A scheme for the functional zone division of Qinhuangdao City is proposed in this study. It is hoped that our study will contribute to the reasonable utilization of the coastal zone resources, achieve the equilibrium and optimization of economic, social and environmental benefits, as well as the sustainable development of coastal economy of Qinhuangdao City, Our research is based on field survey and thorough data analysis while giving full consideration to the coastal type and resources environment of Qinhuangdao City. Six functional areas are divided, and we separately focus on the distribution, resources advantages, main function and environmental protection of these functional areas. The current status and existing problems of coastal resources development are reviewed. Finally, we propose suggestions concerning the orientation of further coastal resources and provide reference for scientific utilization of coastal resources.

Conventional dissolved organic nitrogen (DON) measurements for water samples with high dissolved inorganic nitrogen (DIN) to total dissolved nitrogen (TDN) ratio are incorrect due to the cumulative analytical errors of independently measured nitrogen species (DIN and TDN). In this study, we present a nanofiltration (NF) pretreatment to increase the accuracy and precision of DON measurements by selectively concentrating DON while passing through DIN species in water samples to reduce the DIN/TDN ratio. Compared to the available dialysis pretreatment method, the NF pretreatment method shows a similar improved performance for DON measurement for aqueous samples and can save at least 20 h of operating time and a large volume of deionized water, which is beneficial for laboratories involved in DON analysis. To prove the feasibility of the pretreatment, we collected and compared effluent samples from two sewage water treatment plants. The result shows that with the pretreatment, the DIN to TDN ratio has significantly decreased while the dissolved organic carbon (DOC) recovery has been increased. So this NF pretreatment is available.

This study focused on using liquid Chromatography Tandem Mass Spectrometry to detect N-Nitrosodimethylamine (NDMA) at trace concentrations in water. The water sample was preconcentrated by solid-phase extraction method. To find an elution which can obtain higher recovery, three reagents with different organic solvents were examined. After comparing the recoveries and the standard deviation of the elution, finally the dichloromethane was determined as the elution of the experiment. Then the concentrated sample was analyzed by a method combining SPE pretreatment and LC separation with tandem mass spectrometry using multiple reaction monitoring (MRM).