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The poor corrosion resistance of magnesium alloys become the bottleneck restricting its development. Based on micro-arc oxidation (MAO) technology and the characteristics of fluorocarbon coating the surface of magnesium alloy build a high corrosion protection system, namely: Based on micro-arc oxidation coating fluorocarbon coatings. The formation of the composite coating through the resistance to ageing test through the resistance to ageing test, acid and alkali experiment and salt spray test results show the excellent corrosion resistance performance. Among them, the resistance to salt spray test time can reach 1500 h, which breaks the bottleneck of magnesium alloy corrosion resistance of 1000 h.

Based on the axial-flow fan with adjustable vanes in a power plant of Tangshan, the internal flow with different inlet speeds during the axial-flow fan run were simulated with FLUENT software package. The results showed that if inlet velocity was greater than the critical velocity, the flow was relatively uniform. If inlet velocity was lower than the critical velocity, a vortex caused by tip leakage would decrease fan efficiency and induce surge.The impact increased gradually with increasing of the moving blade angle. The results were consistent with the actual and provided further evidence for high efficient and safe operation of axial-flow fans.

The second harmonic of a pulsed Nd: YAG laser (532 nm) has been used for the ablation of aluminum alloy in air at atmospheric pressure and the laser-induced plasma characteristics are examined in detail. The electron density of 6.7 × 1017cm-3is inferred from the Stark broadening of the profile of Si (I) 288.16 nm, while the plasma temperature (5982 K) is obtained using the Boltzmann plot method of four neutral aluminum lines. The calibration curve for silicon is established using a set of six samples of standard aluminum alloy, and its limit of detection is 0.0681 wt%. The plasma is verified to be in local thermodynamic equilibrium (LTE) based on the experimental results.

The MgTiO3 and CaTiO3 powders were synthesized by solid reaction method, and MgTiO3-CaTiO3 ceramic was prepared using pressureless sintering method. The experiment prepared MgTiO3-CaTiO3 ceramics with high compactness and stable permittivity by the way of changing the mole ratio of MgTiO3 and CaTiO3 to investigate the effect of CaTiO3 on the performances of MgTiO3-CaTiO3 ceramics. The results show that Mg2TiO4 formed as second phase during sintering. Volume density and dielectric constant of MgTiO3-CaTiO3 ceramics with 10%mol CaTiO3 reach maximum of 3.612g/cm3 and 17.8, respectively, under 1460°C sintering temperature. And for the MgTiO3-CaTiO3 ceramics with 5%mol CaTiO3 the maximum values which are 3.5g/cm3 and 16.6, respectively, appear under 1510°C sintering temperature.

Field experiments were conducted for controlled and mid-gathering irrigation mode in Nanjing, Jiangsu Province, focusing on the effect analysis of this mode with different fertilizations on profile soil total nitrogen and alkali-hydrolyzale nitrogen distributions and rice yield compared with the conventional irrigation mode. Results obtained showed that both total nitrogen and alkali-hydrolyzale nitrogen in soil profile were decreased with the increase of soil depth. Fast decrement of total nitrogen was found from surface 0-20 cm of soil layer and it reached the plateau below 40 cm of soil layer. Under the same fertilizer application, both total nitrogen and alkali-hydrolyzale nitrogen in surface soil layer were lower under controlled and mid-gathering irrigation mode which reduced the loss risks of runoff and leaching of soil and fertilizer nitrogen. Controlled and mid-gathering irrigation reduced water comsumption and N pollutant discharge without significant changes in rice yield compared with conventional irrigation. Conjunction of organic and inorganic fertilizers significantly improved the rice yield and utilization rate of nitrogen.

Dressing field control of band gap reflection is investigated in an inverse Y-type four-level atomic system. It is shown that when the dressing field is blocked, a band gap reflection with a maximum bandwidth and nearly ~90% reflectivity can be achieved for the detuning of the coupling field . When a weak dressing field is applied to the system (the intensity is much less than that of the coupling field), a narrowing top flat with ~86% reflectivity of the band gap reflection is observed in comparison with that in the first case. We also show that the band gap reflection can be dramatically suppressed due to the collapse of the stop band when a strong dressing field (the intensity is comparable with or larger than that of the coupling field) is employed. This control of photonic band gap reflection can be used in the applications of all-optical reflection mirrors and band optical filters.

The micrographs and optical properties of Al-doped ZnO (AZO) films deposited by radio frequency (RF) magnetron sputtering are presented in this paper. The AZO films termed as films I, II and III were sputtered on glass substrates heating at 300C, 400C and 500C, respectively. The micrographs, crystal structures and optical properties of AZO thin films were analyzed by using scanning electronic microscopy (SEM) images, X-ray diffraction (XRD) pattern, optical transmission and reflection spectra ranging from 350 to 1000 nm. As the substrate temperature increases to 500C, the film III exhibits a better flatness surface and a larger grain size of ~25nm with a stronger c-axis orientation. The film II has a high transmittance of greater than 92% in the visible light region. We also show that the films II and III have significant red-shift band gap ~3.00 and ~3.13eV, respectively, in comparison with that of the film I (3.31eV). This might be due to the increasing doped Al atoms which do not activate due to segregation at the grain boundaries.

Differential synthetic aperture radar Interferometry has been widely applied to monitor mining subsidence for its high spatial resolution, competent accuracy and wide coverage. In this paper, we introduce the principles of InSAR, discuss several key technical issues in mining subsidence monitoring, including selection of SAR images, advanced algorithms for phase unwrapping and Persistent Scatterer InSAR technique.

As a research object, the samples with various Ba/Ti ratios (Ba/Ti=0.95~1.05) were synthesized by solid phase reaction method. Effect of sintering temperatures and Ba/Ti ratio on dielectric properties and crystal structure of BaTiO3ceramic were investigated. Crystal structure and crystal phase composition were investigated by scanning electron microscopy and X-ray diffraction. The dielectric properties were studied by Agilent 4294A at 1 kHz. The results show that the BaTiO3ceramic has high permittivity and dielectric loss at 1340°C. The permittivity of BaTiO3ceramic with Ba/Ti=0.95 change small as the sintering temperatures vary at 1320°C. With the increasing of Ba/Ti ratio, the Curie temperature first increases and then decreases as the sample sintering at 1320°C. When Ba/Ti=1, the Curie temperature increase with the sintering temperature increasing.

The chemical composition of a 960 Mpa grade high strength steel with low carbon equivalent was designed. Effect of direct quenching and tempering process on the microstructure and mechanical properties of the experimental steel was studied. Results showed that fine lath martensite was obtained after controlled rolling and direct quenching. With tempering temperature increasing, the mechanical properties showed different trends for different tempering stages. And this had a direct relationship with the microstructure evolution. The matrix recovery softening, carbon desolution and precipitation of nanomicroalloy carbides influenced the strength change. With increase of tempering time, the strength decreased and toughness improved. Experimental steel tempered at 450 °C for 40min could obtain the best mechanical properties, which meet the requirement with a large impact energy margin.

Currently, the development of our pipeline inspection technology is rapidly, pipeline inspection robots were widely used , it providing scientific and accurate detection data for pipeline maintenance and overhaul. The accurate localization datas provided by pipeline robots are the basis for pipeline maintenance and overhaul.This paper describes the running Principle of mileage wheel, detailly analysis the reasons of the mileage wheel localization errors according problems appeared.finally, proposed methods to improve pipeline inspection robot mileage wheel localization accuracy briefly.

We examine two-photon selective reflection (SR) spectroscopy in a system of -type three-level atoms at the interface with a ferroelectric layer on a dielectric surface. Two-photon SR lines, exhibiting Dicke-narrowing profiles due to atom-wall collision and Doppler free configuration, are periodically modulated by the thickness of the atomic vapor. These SR lines can be modified by the thickness and the complex refractive index of the ferroelectric layer, and can probably be a feasible method used in the measurement of the optical parameters of the ferroelectric layer.

Frequently, offshore oil spills have a significant impact on the marine environment and fishery resources, resulting in huge economic losses. Due to a lot of projects are involved in oil spill and the process is complex, the injured party lacks the evidence to support the evaluation of the oil spill impact on the environment. Therefore, many oil spill claims event had not been properly resolved. In this paper, we designed an environmental impact assessment system of offshore oil spill for improving the above-mentioned situation. The major functions of this system are data management, query analysis, spatial modeling analysis, evaluation of forecast, user management and so on. Environmental impact assessment system of oil spill can predict and evaluate the oil spill’s impact on environment. It’s significant for the protection of the environment and planning. In addition, it also has a realistic significance for providing some basis for claims issues.

Stable epistemologies and Internet QoS have garnered minimal interest from both cyberneticists and physicists in the last several years. Given the current status of semantic communication, scholars obviously desire the emulation of model checking. In this position paper, we concentrate our efforts on proving that suffix trees can be made homogeneous, scalable, and low-energy. Results showed that the well-known constant-time algorithm for the evaluation of DHCP is optimal, and ShernCod is no exception to that rule. Furthermore, our application successfully analyzed many flip-flop gates at once. This paper also disconfirmed not only that multi-processors and Smalltalk can collude to fulfill this objective, but that the same is true for model checking. Finally, this study provided evidences that the well-known pseudorandom algorithm for the improvement of 802.11b is in Co-NP.

This study investigated the effect of cationic, anionic, and nonionic surfactants on the formation, morphology, and surface properties of TiO2 nanoparticles synthesized by modified sol-gel method. The crystalline structures and morphologies of the powder have been characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The XRD results showed TiO2 nanoparticles synthesized with different surfactants only include anatase phase. The TEM analysis revealed the surfactants can enhance dispersion of TiO2 nanoparticles. In contrast, the anionic surfactants showed hightly effects. The photocatalytic activity of samples was tested for degradation of methyl orange (MO) solutions. The results showed photocatalytic activity of the catalyst with surfactants was higher than pure TiO2 under ultraviolet.

Cu-based nanometer composites with ω（n-SiO2）=1.0 % nano-SiO2 were prepared through ball milling and powder metallurgy technology. The friction and wear performance of the composites was investigated by ball-disk friction and wear tester. The microstructure and wear morphology were studied by drainage and field scanning electronic microscope (FSEM), respectively. The results indicate that ball milling can improve the spatial distribution of nano-SiO2 in the copper matrix. With the ball milling time increasing, the dynamic friction coefficient and wear rate of the composites decrease firstly and then increase. The composite milled 10 h has the lower friction coefficient and wear rate, and its main mechanism is abrasive wear.

Using China health and Nutrition Survey (2006) data and probit regression model, this paper examines how public living environment affect health, it also examines urban-rural differences and regional differences in China. Through analysis, it finds that living environment is a key health impact in China, and drinking water and toilet situation in rural and western China are closed related to health. The evidence will provide reliable information for health policy formulating.

Finite element analysis software ANSYS analysis a combination sections beam which has contact surface and a integral model. Then find out the difference to identify the overall model and the parts beam dynamic differences. According to the result learn the contact surface how to influence the tools dynamic. It can offer theoretical and practical basis for design and structure optimization.

After a deep investigation on the nth canonical roots of matrices, we establish the key theorem concerning how to find the n-th canonical roots. Relationship between canonical roots of a complex matrix and its n-th roots is also investigated.. Existence of canonical roots is not true for arbitrary matrix. By investigating the extension rule, this paper introduces the concept of canonical roots and gives an algorithm determining the form of canonical roots.

Microwave-assisted extraction (MAE) was used to extract chlorophylls from filter mud. Ethanol was used as the solvent. The optimal conditions for the MAE of chlorophylls were concluded from the study as the irradiation time, 50 s, the ratio of liquid to solid, 8:1 (mL/g), the extraction temperature, 40 °C, and the extraction time, 60 min. Compared with conventional extraction, the MAE of chlorophylls from the filter mud was more effective. The extraction time for MAE was 60 min with 0.277 mg/g chlorophyll yield, while conventional extraction needed 240 min with only about 0.259 mg/g chlorophyll yield. The Ultraviolet Absorption Spectra of the extracted chlorophylls showed that there was a strong absorption peak at about 663 nm. C=N, Mg-N and C-N was not seen existed from the infrared spectroscopy probably because that the mixed extracts were not purified and the chlorophyll content was less.

The fatigue behavior of cast steel ZG20SiMn under strain control mode was investigated, and the influence of imposed total strain amplitude on the cyclic deformation and fracture behavior of the cast steel ZG20SiMn was determined. The experimental results reveal that during fatigue deformation, the cast steel ZG20SiMn may exhibit the cyclic strain hardening and stable cyclic stress response behavior, which mainly depends on the imposed total strain amplitude. The relationship between plastic and elastic strain amplitudes with reversals to failure shows a single linear behavior, and can be well described by the Coffin-Manson and Basquin equations, respectively. At different total strain amplitudes, the fatigue cracks initiate at the free surface of fatigue specimens and propagate for the cast steel ZG20SiMn.

In electric machinery performance test, tooth harmonic time-frequency characters of first order of three-phase cage asynchronous motor are most important. The MATLAB software is used to make model and simulate the starting characteristic of asynchronous motor in this article, while the stator current signal of starting motor is de noised by wavelet transform. Through decomposition and reconstruction of wavelet transform, the amplitude of fundamental and harmonic wave in de noising stator current can be reduced, and then the tooth harmonic of first order of starting rotor is extracted. Using the excellent time-frequency analyzing characters of wavelet package transform, the tooth harmonic time-frequency curve is fitted.

Education informationization of primary and junior school is the foundation and conditions for achieving the education modernization, It is the important content and main symbol of education modernization。This paper take Xinxiang city as an example, Through the analysis on the hardware and software facilities, teachers, information technology course,etc，to expound the difference between Urban and Rural during Educational Informatization of the Primary and Junior School， and submit corresponding resolving strategies.

Copper coated nano-SiO2 composite particles were prepared by mechanical milling technology. The effects of milling time on morphology, granularity, component and microstructure of the composite particles were characterized by scanning electronic microscope, laser particle size analyzer, energy depressives spectrometer and transmission electron microscope, respectively. Results showed that dendrite composite particles change to the flaky, and then to spherical ones with the milling time increasing. The particle size decreases firstly and then increases with the milling time increasing. The n-SiO2 particles disperse more homogeneously in the composite particles with the milling time increasing.

The Cu-based friction materials with nano-graphite were prepared through powder metallurgy technology. The microstructure and friction performance were studied through scan electronic microscope (SEM) and friction tester, respectively. The results indicate that coefficient of the Cu-based friction materials with 2 wt% nano-graphite is high and stable. Comparing with the friction materials without n-C, the wear resistance and heat resistance of the friction materials with nano-graphite has been improved by 11 % and 25 %, respectively. The nano-graphite particles will reduce the abrasive wear and enhance the wear resistance of the Cu-based friction materials.

In the reservoir water temperature conducted annual test, test data shows that water temperature perennial remain in 9 ~ 10 in certain depth below. Reservoirs and lakes are huge natural cold source. In an air conditioning engineering, the reservoir cold water was directly used as cooling source. The air conditioning effect is good and to gets good energy-saving and environmental benefits. It suggests that solar energy, natural ventilation and natural cold and heat storage in water should be widely used in the western tourist architecture in order to achieve low carbon tourism.

By reactions of indium chloride tetrahydrate with three bis-Schiff bases ligands (N, N’-bis (3-methoxy-salicylidene)benzidine = L1; N, N’-bis (3-methoxysalicylidene)-2, 2’-dimethyl- benzidine =L2; N, N’-bis (3-methoxysalicylidene)-o- dianisidine = L3), respectively, three novel corresponding complexes 1~3 were obtained. The complexes were characterized by infrared spectrum, molar conductance, elemental analysis and thermal gravimetric analysis. The chemical formulae of the complexes 1~3 were determined as (InCl3)2Ln (1, n = 1; 2, n = 2; 3, n = 3). All the complexes are constructed with binuclear indium ions. Every complex consists of two central In (III) ions, one corresponding bis-Schiff base ligand and six Cl-.

Pleurotus nebrodensis were packaged with PVC and PE with different thickness (0.03 mm and 0.05 mm) at 4°С. Package gas composition, respiration rate and relative electrolyte leakage were measured during storage at 4°С and 95%RH for 28 days. The results showed that auto modified atmosphere pattern would be formed at 7th day of the storage. The atmosphere concentration in the package of 0.05 mm films was 0.1~5% O2and 6%~10%CO2after 7days, then maintaining the atmosphere concentration stable in the following days of the storage test. Compared to the 0.03 mm film, the 0.05 mm film was more effective for decreasing respiration rate and electrolyte leakage of pleurotus nebrodensis to delay its senescence. It could be taken for granted that pleurotus nebrodensis was apt to storage in the circumstance of low O2and high CO2.

In this paper, various kinds of high-temperature phase change thermal storage Al-Si-Cu-Mg-Zn alloys were prepared, and the thermal properties were studied through integrated thermal analysis. Then the corrosion kinetics of Cr20Ni80 alloy in Al-7% Si alloy and Al-Cu-Mg-Zn alloy at 700°C in thermal cycles were obtained. The microstructures, element concentration and phases in the interface were analyzed by means of metallographic microscope, EPMA and XRD. The results show that all materials phase transition temperatures are during 450°C ~650°C . The total thermal energies of the materials are higher than 900J/cm3. Quaternary alloys and quinary alloys show much more advantages when applying for solar thermal power generation systems. The latent heat depends strongly upon the composition and percentage of elements and the phase composition. Besides, experimental results show that the corrosion rate of Cr20Ni80 alloy in Al-7%Si alloy at 700°C is 0.167mm/h. Under thermal cycling conditions, the corrosion rate of Cr20Ni80 alloy in Al-Cu-Mg-Zn alloy is a little lower and the reaction interface layer does not significantly affect the rate of further corrosion. The corrosion of Al-Si-Cu-Mg-Zn phase change thermal storage materials depends on the content of aluminum element, and nickel-based alloys are not suitable for use as packaging materials.

The wireless sensor networks have been extensively deployed and researched. One of the major issues in wireless sensor networks is the energy consumption program. In this paper, we analyzed the development status of wireless sensor networks and the problems,while proposed the network structure and energy model,then we discussed the energy saving strategies for wireless sensor networks from four aspects:First analysis the component of WSN protocol stack and the energy consumption;Second,we study the energy-saving strategy for a single node from the computing subsystem and the communication subsystem,and we introduce a new long-sleeping status to save energy through using Flag mark.Third is the energy-saving optimization strategy based on communication protocol which mainly discuss from MAC and routing protocols.Last,we discuss the topology control strategy for energy-saving and point out the importance of topology control technology. Use these strategies, we can significantly reduce the energy consumption of wireless sensor networks and extend the network life-cycle.

The effects of MA packaging on nutritional value and quality of honey pomelo have been investigated during storage at 8 . Results show that 25μm-thick PE films maintained more suitable headspace gas concentrations for preservation of pomelo than 50μm-thick PE films and microperforated 25μm-thick PE films (control). The 25μm -thick PE films have the highest value on quality parameters, which were 12.2%, 0.9%, 47.1mg/100g and 44.8mg/100g for total soluble solid, titratable acidity, vitamin C and total phenolic content after 150 days of storage, respectively. This study suggests that MA packaging with 25μm-thick PE films show the best effects in maintaining the quality of honey pomelo during storage at 8 .

Taking pleurotus nebrodensis as a test material to research the pleurotus nebrodensis preservation effect with using modified atmosphere packaging of PE with different thickness at 4 , evaluating the quality changing during the storage life. The results showed that 0.05mmPE treatment has the best preservation effect, which could effectively maintain the storage circumstance of low O2 and high CO2 concentration, decreasing the weight loss and postpone the reducing of luminosity L and browning time. Besides, using modified atmosphere packaging of 0.05mmPE can postpone the decline of quality of pleurotus nebrodensis, enhancing the storage quality and prolonging the life of postharvest storage as well.

Chinese jujube (Zizyphus jujuba M) fruit at the postharvest stage was easily have a dramatic decline in quality. The effect of 1-MCP and CaCl2 in delaying fruit ripening and improving storage quality was investigated through this study. Chinese jujube fruit were harvested and then treated with 1µL L-1 1-MCP for 24 h at 20°C, immersed in 1% CaCl2 solution for 10min and their combination, then kept 0 °C and 80–90% RH after treatment. Results indicated that 1-MCP and CaCl2 were effective in terms of senescence inhibition during storage and compared to control, and the performance of 1-MCP was little better. Fruit treated with 1-MCP and CaCl2 had ability to maintain firmness, soluble solid concentration (SSC), weightlessness, membrane permeability. The ethylene production rates of jujube fruit were effected significantly by treatment with 1-MCP, not affected by CaCl2 treatment like control samples, however, they both had a visible influence on the content of MDA compared fruit with untreated. Furthermore, treatment with 1-MCP + CaCl2 resulted in additive beneficial effects on ripening inhibition of the fruit and maintaining the qulity of Chinese jujube fruit.

In order to obtain the important liquid crystal intermediate with trifluoromethyl substitutent, Sonogashira coupling reaction was used to synthesize the compound. In this paper, the intermediate was synthesized by 4'-Iodo-4-pentyl-biphenyl and trimethyl silyl acetylene (TMSA) as raw materials. During the synthesis, the optimum reaction conditions were obtained, that the mol ratio of 4'-Iodo-4-pentyl-biphenyl and trimethyl silyl acetylene is 1:2, the reaction temperature is 30 oC, and the reaction time is 10 h.