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Using ammonium chloride (NH4Cl) as model compounds of ammonia nitrogen metabolites of crassostrea rivularis (oyster), the corrosion process of steel alloys by ammonia nitrogen metabolites of oyster was carried out in simulated seawater. Using A3 steel for marine engineering steel as the sample, the experiments based on the corrosion coupon in natural sea, static coupon, scanning electron microscope and polarization curve were carried out. According to the corrosion morphology development of samples, the corrosion mechanism of attached corrosion of was revealed.

This paper introduced the research status of microgrid control system(MCS) and analyzed the functions of microgrid control center(MCC). A design of multi-functional of microgrid control center was presented , and each relevant functional module was described.

The development and application of energy storage technology was described. Based on wind power fluctuation limit and system peaking demand in the smart grid, a novel optimized operation strategy between wind power and energy storage devices. The correctness of the strategy is verified by numerical example.

The operating status of the microgrid is given, currently three classic control modes of microgrid isintroduced. And a method is put forward, which is a improved active power-frequency droop control method based on Lagrange interpolation.This method can effectively guarantee the stability of the microgrid running frequency. The correctness of the method is confirmed through the simulation.

Control strategy of inverter is the foundation of microsource’s power control. Based on a typical system setting method, double-loop control system of LC filter and inverter for voltage-source inverter in microgrid is designed. The feasibility is verified via the simulation.

When in grid-connected operation, the microgrid exchanges power with main grid as a whole, real-time price was analyzed on the basis of binary chaotic particle swarm optimization algorithm. Through imulation, it was verified that the control strategy taking into account the real-time price is economical and reliable.

This paper introduced the research status of microgrid control system (MCS) and analyzed the functions of microgrid control center (MCC). A design of multi-functional of microgrid control center was presented, and each relevant functional module was described.

A fuzzy decision model is built to analyze correlation of historical load datas, and to preprocess original datas, by extracting useful datas contributing to forecasting and removing "bad datas". Then the neural network model (NNM) is established to predict power load value measured at 96 time points, through accurate analysis, the rationality of the model is verified.

How to ensure the security, stability and economic operation of microgrid in different operation modes is a difficult problem of microgrid research. There is active power and reactive power coupling in the regulation of frequencies and voltages because of the line parameter characteristics of microgrid. The defect of the traditional active power-frequency, reactive power-voltage droop control is analyzed and a novel decoupling droop control method for low voltage microgrid is proposed in this paper. At last, the multiple feedback loop control strategy for inverters on the basis of this proposed method and a microgrid simulation model are established. The comparative analysis between the new method and the traditional method based on the simulation results can prove that the proposed control method is simple in design, and it can assure an excellent power quality and realize the reasonable distribution of active power and reactive power between distributed generations.

A trinuclear Chromium(III) complex [Cr3(μ3-O)(μ2-PCBA)6(CH3OH)3]NO3∙H2O∙CH3OH (HPCBA = 4-Chlorobenzoic acid) has been synthesized and characterized by single-crystal X-ray diffraction, IR spectra, UV-Vis absorption spectra and elemental analysis, which belongs to monoclinic, space group P21/c with a = 12.443 (3), b = 24.543 (5), c =22.094 (7)Å, α = 90°, β =115.76 (2) °, γ =90°, V = 6077 (3)Å3, Z = 4.The surface electron behavior of the chromium complex has been studied emphatically by surface photovoltage spectroscopy (SPS). Structural analyse indicate that the complex is molecular complex. The result of SPS show that there is positive photovoltage response bands within 300–800 nm, which indicate that it possess obvious photoelectric conversion properties. There was a good correlation between the SPS and UV-Vis absorption spectra.

In order to investigate the characteristic of the supersonic jet screech tones, an experimental bench of the supersonic jet was designed and a free field noise signal acquisition system was established. Effects of the nozzle size and jet Mach number on jet noise sound field distribution was analyzed, through the result comparison of supersonic jet noise experimental measurement. Results indicate that the field distribution of supersonic jet screech tones is characterized with very strong directivity. Peak value of the screech tones decrease and occurrence frequency of the screech tones increase with the decreasing jet exit Mach number; occurrence frequency of the screech tones decrease with the increasing nozzle size, but the peak value change very less. The experimental measurement of supersonic jet noise provides mechanism research of sound production with data supports and references; and also provides the numerical modeling of supersonic jet noise with validation criteria.

A systematic study has been undertaken to quantify the effects of jet Mach number and nozzle size on the noise radiated by supersonic jets. All the tests were carried out at an experimental bench of the supersonic jet. Results indicate that the field distribution of supersonic jet screech tones is characterized with very strong directivity. Under the textual experimental conditions, if the jet Mach number remain unchanged, the diameter of nozzle throat increases gradually from 5mm to 8mm or 10mm, and the amplitude values of both the turbulent mixing noise and broadband shockwave correlated noise increase by 2-5dB, and the amplitude value change of the whistler type noise is not obvious, and the occurrence frequency of the whistler type noise decreases by more than 2000Hz; if the jet Mach number increases to 3.0 from 2.0, the amplitude value of the whistler type noise increases by more than 2dB, and the occurrence frequency of the whistler type noise decreases obviously. The experimental measurements of supersonic jet noise provide the sound production mechanism research on the supersonic jet noise with data supports and references and provide the numerical modeling of the supersonic jet noise with validation criteria.

Gas-steam launching system with water injection in block can overcome the problem of horizontal or large-angle launching, and gets more and more value in recent years. Based on the characteristic of launching system, the model was built with several assumptions, which could provide reference and technique for developing the new launching system. And the generator result was verified by the experimental one. The interior ballistic characteristics were researched by calculation result under different deep and injection water mass conditions. The comparison of the simulation results and theory analysis indicates the model was rational and valid, and different launching deep and cooling water mass had effect on ballistics, more water can cool down the silo, but also brings more energy loss, and deeper launch needs more energy, so good design is required to fit the parameters demand in all respects.

the risk assessment for development project is simply and highly efficient, requires less data, and can clearly uncover the problems. It is plausible to evaluate a plenty of development projects through computers

The title compound, [Na(μ1,1,2,3-oxalato)(di-μbelongs to triclinic, space group P-1 with a = 5.6982 (11), b = 6.5040 (12), c = 6.6647 (13) Å, α = 75.040 (2), β = 84.990 (3), γ = 70.072 (3), V = 224.34 (7) Å3, C2H3NaO5, Mr = 130.03, Z = 2, Dc = 1.925 g/cm3, μ = 0.270 mm–1and F(000) = 132. Each sodium ions is located on crystallographic inversion symmetry centre and surrounded by six oxygen donors from three oxalate ligands and two di-μ1,1-waters in a distorted octahedron geometry. Two planar 4-member cyclβes crystallographic inversion are found in alternate repeated Na2O2subunit, which is further extended to two dimensional supermolecular fragment via μ1,1,2,3-oxalato-bridged. The crystal structure is aggregated to a 3D network through O-H…O hydrogen bonding involving the water molecules and oxalate oxygen atoms.

This paper describes the design and fabrication of dual-mode film bulk acoustic resonator (TFBAR) devices to construct wafer level dual-band T-ladder type filters. The T-ladder type filters is selected in this study for its high quality and simple fabrication processes. The c-axis-tilted ZnO thin films to obtain dual-mode TFBAR devices have been investigated. The characteristics of dual-mode TFBAR devices appeared by off-axis deposition of ZnO thin films with the RF magnetron sputtering. The top and bottom electrodes consisted of titanium (Ti) and platinum (Pt) layers are deposited by dual-gun DC sputtering system. The pass-band width of filters is controlled by the mass loading on the dual-mode. The frequency response is measured using an HP8720 network analyzer and a CASCADE probe station.

This project is intended to design one kind of automatically reciprocating pedal-powered electricity generator (ARPPEG) in conjunction with the management and control over harvesting the kinetic energy, electricity generation, the electricity storage and the output of electricity. According to the operation testing results, this system has been proved to effective in power generation. In view of the simple structure and low-costs of this system without territory and time limits, the application of ARPPEG designed by us could open a new path to saving the energy and helping build a new energy society.