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Recently, the high Al-added light weight steels are particularly attractive for automotive applications because of their excellent mechanical properties and weight reduction. In this study, the microstructure characteristics and hardness in the resistance spot welding of high Al-added light weight steels were investigated. A Al-added 780MPa steel and Al-added 980MPa steel were used in the present study. For Al-added 780MPa steel the hardness in the weld nugget was higher than that of the base metal, and reduced hardness between the weld nugget and base metal is due to the presence of soft δ-ferrite. For Al-added 980MPa steel the hardness in the welt nugget was lower than that of the base metal due to grain growth.

The effects of the alloying sequence and refining time on the inclusions in Fe–9Cr alloy reinforced with Y2O3 nanoparticles were investigated. The size and number of inclusions in the alloys were determined via optical microscopy, and their morphology and composition were determined via scanning electron microscopy. The Y2O3 mainly acted as a nucleating agent in the Si–Mn+Y2O3+Ti alloying process, promoting the precipitation of other oxides, which was beneficial for the formation of Y–Ti–O particles. In contrast, no Y–Ti inclusions were formed when the Si–Mn+Ti+Y2O3 alloying process was employed. In addition, the inclusions in the alloy tended to stabilize after refinement for 5–10 min. This study offers a general pathway for the manufacture of oxide dispersion strengthened steel via a smelting process.

Surface self-nanocrystallization (SSNC) is a new surface modification technology to develop new materials, which can obtain nanostructured layers with nanograins on the metals surface without changing the chemical composition of the metals. In this study, SSNC was introduced from the aspects of the preparation methods, microstructural mechanism, mechanical properties, surface roughness, corrosion resistance and applications. This paper will provide experience and reference for further comprehensive researches and industrial applications of SSNC.

Recently, the weight reduction of automotive body and crash safety become much more important factors. In addition, the corrosion resistance must be ensured for any material used in a structural part of automotive components. In an effort to satisfy these requirements, zinc-coated high strength steels have been developed. However, challenges to resistance spot weldability of zinc-coated high strength steel such as liquid metal embrittlement (LME) have emerged. In this study, the high temperature tensile test was conducted for 980MPa DP steel. And resistance spot welding was conducted for 980MPa DP steel and CP steel. The results show that the fracture behavior during tensile test are influenced by the temperature and strain rate. Cracks were formed on the weld surface of the DP steel after welding.

Semi-solid CuSn10P1 alloy slurry was fabricated by a novel enclosed cooling slope channel (for short ECSC). The effect of filling velocity on microstructure and properties by squeeze casting was studied. The results showed that primary α-Cu phase gradually formed from dendrites evolved into worm-like or equiaxed crystals by ECSC. As the filling velocity increases, the ultimate tensile strengths and elongations of the shaft sleeve increase first and then decrease. The ultimate tensile strength and elongation of semi-solid squeeze casting CuSn10P1 alloy reached a maximum of 417.6MPa and 12.6% when the forming pressure is 100MPa and filling velocity is 21mm/s, which were improved by 22% and 93%, respectively, as compared to that of liquid squeeze casting.

Intermediate temperature creep properties are considered a key indicator of single crystal superalloys used for turbine blades of aircraft engines. The interrupted and ruptured creep tests were carried out in a second generation single crystal superalloy under the conditions of 760°C/785MPa. The creep rupture life as well as minimum creep rate were also in the same level of those in CMSX-4 and PWA1484. The microstructural evolution at different creep stages were analyzed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed the γ’ phases kept the cuboid morphology mostly until the creep rupture, and super lattice stacking faults (SSFs) extended along [-1 1 0] and [-1-1 0] orientations within the γ’ precipitate were the typical dislocation configuration.

The WC particles reinforced iron matrix composites were prepared by utilizing energy ball milling powder mixed and vacuum powder sintering method in this paper. The effects of two kinds of matrix on the micro-structure, interface and fracture mechanism of the composites were studied emphatically, and it provided a theoretical guidance for the design and engineering application of particle reinforced metal matrix composites. The results show that: in the two kinds of matrix composites, WC particles and interface had different degree of melting, WC particles and the matrix were metallurgical combination; ferritic matrix composites had better compressibility than pearlite matrix composites (1089Mpa); the fracture mode of ferrite matrix composites was quasi-cleavage fracture and pearlite matrix composites was pure cleavage fracture; the compressive micro-cracks of the two matrix composites generated at the interface and expand at the interface to a broad macroscopic crack, which eventually the material fails.

The MEA-DEAB-CO2-H2O solutions contain complex ions in the solution. Carbamate (RNH-COO-) and bicarbonate (HCO3-) anions are the major format of CO2 dissolved in the solutions. The ion concentrations of both components are constrained by the reaction equilibrium and VLE model of CO2-amine interactions. For the MEA-CO2-H2O systems, the majority of [CO2]0 is carbamate. For the DEAB systems, the majority is bicarbonate. The blended amine system such as MEA-DEAB-CO2-H2O contains both carbamate and bicarbonate at different ratios, which is affected by variations of amine ratio, CO2 loading and operation temperatures. This work summarized VLE plots from 13C NMR analysis of single and blended amine solutions, both in room temperature (24°C) and higher temperature (70°C) to detect trend of the ratio of bicarbonate vs carbamate in the blended amine (MEA-DEAB) systems under both absorption and regeneration conditions. These experimental data indicated the carbamate exchange reaction is endothermic. With increase of temperature, ratio of bicarbonate increased accordingly and that of carbamate decrease. The increased concentrations of bicarbonate can facilitate the amine regeneration with reduced heat duty.

Surface modification of nanoAl2O3 with stearic acid by dry method was researched. The structures of nanoAl2O3 before and after modified were characterized by IR. The modification effect on nanoAl2O3 was measured with the activation index. In addition, the influence factors of modifier dosage, modification time and modification temperature were also discussed. The results showed that nanoAl2O3 had been successfully modified with stearic acid. The hydrophily and lipophilicity experiments indicated that modified nanoAl2O3 possessed lipophilicity property and could disperse in xylene. The optimal conditions of modification were as follows: the stearic acid was 7.5 wt%, based on the quality of nanoAl2O3, modification time was 50 min and temperature was 150 ○C.

Powder metallurgical (PM) route is one of the methods for metal foam fabrication. In this paper, we report the fabrication of Zn alloy foams with 0~50wt.% Mg via powder metallurgical approach by using CaCO3 as the blowing agent. The fabrication process included 5 steps: powders mixing, cool-pressing, heat treatment, hot-pressing, foaming and cooling. The effects of Mg addition, foaming temperature on the foaming process were discussed. Finally, the compressive behavior of Zn alloy foam was evaluated.

Ionic polyurethane (IPU) was synthesized as shape memory materials. Poly (tetramethylene ether) glycol with 2000g/mol number average molecular weight were used as soft segment, 4,4-methylenebis (phenyl isocyanate), and 1,2-dihydroxy-3-propanesulfonic acid salt were used to compose the segment of SMP materials. The structure and properties of these IPU films were characterized by Fourier Transform infrared, X-ray diffraction, Thermal gravimetric analysis and Differential scanning calorimeter. The results showed that the glass transition temperature of the IPU increased with the increase of hard segment content. The physical properties in terms of swelling property, water absorption and ion-exchange capacity increased with the improving of sulfonic group content in IPU. The shape memory property of IPU exhibited that the shape fixity ratio and recovery rate improved remarkably with the increase of hard segment content.

With the rapid development of transportation, the vulnerability of bridge under blast loading has more and more attracted people's attention. To ensure the safety of the bridge under the impact of blast loading is very important. This article describes the current situation of bridge structure antiknock research in China and other countries. What’s more, pointed out the shortcomings of existing research and presented that the antiknock research of bridge structure should combine numerical simulation with model test at the same time. This article researches the stress, strain and bridge damage rule of 1: 5 model of T-beam Bridge under explosion effect of small doses explosive.

The microstructures and 500 °C high temperature wear properties of a high boron medium carbon alloy (HBMCA) quenched at 950 °C and then tempered at 500 °C were investigated, compared with a typical high speed steel (HSS). The results showed that the matrix structure of HBMCA after heat treatment was tempered sorbite. The content of herringbone-like and rodlike eutectic decreased. Hard phase precipitation (boron carbon compounds, e.g.M23 (C, B) 6, MB and M3B2) increased in the matrix. And the abrasion resistance of HBMCA after heat treatment at high temperature was 2.39 times of a typical HSS for roller. The wear mechanism of HSS at high temperature is a typical oxide fatigue wear mechanism, while as-quenched HBMCA is oxidation, adhesive wear mechanism.

Hydrothermal synthesis as a new coating technique has been developed to produce biomedical coating in Mg alloys in recent years. This paper summarized the process feature and corrosion resistance of hydrothermal synthesis coating in Mg alloys, and then reviewed the synthesis process, microstructure, corrosion behavior and corrosion mechanism of the Mg (OH)2 biomedical coatings. Finally, the current problems and research prospect of this technique in biomedical Mg alloys were discussed.

This paper reports the required conditions for fabricating Mg-Al alloy foams starting from metallic powders, where CaCO3 was selected as the blowing agent. The molar ratio of Al varied from 0 to 50%. Mg-Al alloy foams with porosity of 30%~80% and pore size around 0.5~2.0 mm were prepared successfully. The process to make foams includes two main procedures, i.e. foamable precursor preparation and foaming procedure. The effects of the three main parameters, i.e. compaction degree, Al addition, foaming temperature on the foaming results were discussed. Finally, the compressive behaviors of Mg alloy foams were investigated.

High Voltage Direct Current (HVDC) system was often the link between major power grids. In order to ensure the safe operation of HVDC, fault diagnosis method was studied. The system structure of HVDC Light system was analyzed, and the normal and fault conditions of the transmission system were simulated in the Matlab platform. This method was very convenient and simple, and it could restore the real situation. The use of simulated waveform could effectively identify the fault types of actual situation, and then it was a flexible, efficient and practical method of fault diagnosis in HVDC Light system.

Cerium oxide powder and aluminum foam loaded cerium oxide were prepared by hydrothermal method using cerium nitrate hexahydrate and dimethyl oxalate (DMO) as raw material. Cerium oxide precursors and cerium oxide particles were characterized by field emission scanning electron microscopy (FESEM). Aluminum foam loaded cerium oxide was characterized by environment scanning electron microscopy (ESEM). On the basis of calculation and fitting of the experimental data, effect of the particle size on the adsorption rate, desorption rate and concentration of surface active sites of the powder and composite absorbents were studied. Results show that the removal of fluoride ions can be realized by exchange adsorption of oxhydryl on the cerium oxide particles surface and the fluoride ions in the solution.

A series of bulk ultrafine-grained (UFG) pure iron with grain size of 250-450 nm were fabricated by equal-channel angular pressing (ECAP) and annealing. Effects of ECAP passes on the corrosion behavior of the UFG pure iron were investigated. Results show that ECAP accelerates the acid corrosion rate of pure iron, but improves its anodic passivation property. The acid corrosion resistance of the UFG pure iron is restored through a large number of ECAP passes as well as through an annealing treatment. Annealing treatment is not good for the anodic passivation property of the UFG pure iron after a small number of ECAP passes. However, after a large number of ECAP passes (up to16), the corrosion resistance and anodic passivation property of UFG pure iron are less affected by annealing.

Recently, the weight reduction of automotive body and crash safety become much more important factors. In addition, the corrosion resistance must be ensured for any material used in a structural part of automotive components. In an effort to satisfy these requirements, high strength galvannealed DP steels with 590 MPa in tensile strength have been developed in Shougang. Steel chemistry with low Si was designed to reduce the iron oxidation with chemical composition (Si, Mn etc.) and to improve the wettability by liquid zinc. And the alloying elements (Cr, Mo etc.) were added to improve hardenability of sheet to obtain DP microstructure. Newly developed 590MPa grade hot dip galvannealed DP steels have good mechanical properties and hole expansibility. The results revealed the Cr addition effectively suppresses the formation of ferrite during the continuous annealing to improve the hole expansibility of steels. The galvannealing temperatures are increased to improve the hole expansibility of steels by generating the appropriate amount pearlite.

The progress of adsorption capacity-enhancing modified manganese mineral, as well as the optimal conditions on which the adsorption of modified natural manganese mineral is conducted, are discussed and summarized in this paper. Moreover, the optimal parameters of the adsorption of Cu2+, Ni2+, and As (V) by using natural manganese mineral are respectively presented and the adsorption capacity is compared.

A three-dimensional mathematical model of mold electromagnetic stirring (M-EMS) for round billet was established. Based on Maxwell’s equations, the distribution of electromagnetic field was solved by ANSYS software. Different process parameters’ influence on magnetic flux density and electromagnetic force (EMF) was studied. The results show that the magnetic flux density reaches the maximum at the stirrer center in the axis direction and increases with the increasing distance from the circle center on the cross section of the stirrer center. The tangential EMF is symmetric about the circle center and reaches the maximum at the edge of round billet. Both the magnetic flux density and the tangential EMF increase with the increasing current intensity. With the increasing current frequency, the magnetic flux density decreases, while the tangential EMF increases in the applied range of current frequency for M-EMS.

Acoustic transform algorithm plays an important role in sound pressure reconstruction. According to a new sound pressure reconstruction of near-field acoustic holography based on Fourier transform-source simulation technique, this article through a simulation experiment with the models of Simply Supported Plate Sound Source, verify the feasibility of the method. Furthermore, in order to verify the effectiveness of this method, this paper analyzes the impact factors that affect the accuracy of the Reconstruction. And it does simulation analysis mainly from the parameters of the Virtual Source Plane, the Distance of the Holographic Measurement and the parameters of the Holographic plane. Therefore this study provided referencing basis for later study on complex field of sound pressure reconstruction based on this technology.

The common problem of continuous rigid frame bridge is excessive mid-span deflection. The three factors of excessive deflection including vehicle loads, structural rigidity and prestressed loss are discussed on the case of a three spans continuous rigid frame bridge. Midas Civil is applied to analyze the sensitivity of mid-span deflection for these factors. The results indicate that the deflection is increasing with the increase of vehicle loads or the decrease of structural rigidity or the increase of prestressed loss. Furthermore, mid-span deflection is the most sensitive to the change of prestressed loss.

A biotrickling filter has been set up in WWTP of Nanjing petrochemical factory for about 6 months. The purpose of this project was to assess the ability of the biotrickling filter to remove hardly biodegradable VOCs such as benzene, toluene, ethylbenzene and xylene which are recalcitrant and poorly water soluble and commonly found in petrochemical factories. PUF cubes (1 cm3) were used as the packing media treated with large amounts of circulating mineral salt medium added with bacterial species which came from secondary sedimentation tank of WWTP of Nanjing petrochemical industry. The controlled empty bed retention time (EBRT) of 90 s was a key parameter for reaching a removal efficiency of 91.7 %, 88.3 %, 70.7 % and 63.5 % for toluene, ethylbenzene, benzene and xylene, respectively. The analysis of the bacterial community in the BTF during VOC removal showed that Pseudomonas putida and Klebsiella sp. phylum were dominant microbes.

This thesis introduced the origin and function of traffic calming measures in solving road safety problem and reducing vehicle speed to make the environment more secure, also introduced several different types of basic traffic calming measures. Facts showed that using traffic measures can improve the safety of traffic environment, reduce vehicle speed and decrease accidents and pollutions. Therefore, traffic calming measures should be highly valued by governments and policy makers in constructing a city with harmony and prosperity.

Implement a checkpoint mechanism in the system of loaded BLCR project, to set up checkpoints on the progress which need a quick recovery. The router can receive and save the checkpoint files sent by the other system. When the process need to quickly migrate to the other machines, to use the checkpoint files to recover, ensure the process runs on the other computer from a previous running state. In this way can save a lot of time and resources, and can meet the need of many applications.

A ceramic coating grows on the surface of Q235 carton steel in situ by the micro-arc oxidation method and the silicate electrolyte system; and the phase composition, surface topography and elementary composition of the ceramic coating are analyzed by X-ray diffractometer (XRD), scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (EDS). The results show that the ceramic coating growing on the surface of Q235 carton steel in situ presents an irregular porous structure; and the electrolyte and the element in the basal body exist in the ceramic coating in the form of amorphous state. And then, the author degrades the rhodamine B solution by the home-made ceramic coating and H2O2Fenton system, so that the degradation rate of the rhodamine B solution can reach 97%; and meanwhile, the degradation rate is not reduced along the increased using times.

The precipitates and precipitation kinetics of super austenitic stainless steel with high Mo and N (HHSASS) were investigated by optical microscope (OM), scanning electron microscope (SEM) and quantitative metallography method. The results show that the TTP curves are C-shaped, the “nose” temperatures of precipitation are found to be 1000°C with the incubation periods of 120s and 600s, respectively. At 1000°C, some precipitates form as ellipsoidal-shaped and connect along the grain boundaries first. Then a few precipitates start forming as needle-shaped within austenite grains. Until aging for 300min, the field is filled with needle-shaped precipitates. The main precipitates in HHSASS are Sigma phase and Chi phase that are rich in Cr and Mo. The precipitates on the grain boundaries are ellipsoidal-shaped and those in the austenite grains are needle-shaped. About the structures of precipitates need to be further researched.

Through early interviews 22 common traffic scenes were found and leveled by questionnaires. Six scenes of low-risk, medium risk and high risk were selected and implemented in the simulation software using the software of Creator, Vega, C++, etc. Simulation experiments were conducted to analyze the novice drivers fixation features under different levels of risk based on the designed real car simulation platform. The results showed that both novice and experienced drivers saccade times are more than 3 times greater than the fixation times, suggesting that drivers visual search are found mainly in saccadic movement other than watch movement. In potentially dangerous environment, experience drivers always reduce fixation time and increase saccade time to make early warnings of danger that may arise, while novice drivers saccade time and fixation time are relatively stable. Novice drivers concern more about the dashboard regardless of the level of risk in any scenarios comparatively. In the three levels of risk conditions, novice drivers watching areas are more concentrate, namely, their fixation area mostly focus on some certain areas while ignoring other areas, such as rearview mirror and traffic signals.

Analysis on distribution trends of affecting red tide factors in the Beibu Gulf inshore based on data were monitored by automatic water quality monitoring network in 2011 and 2013, providing the scientific basis for preventing disasters and reducing damages of the red tide. Results showed that, average water temperature of Beibu Gulf are maintained in 21.5 °C ~27 °C in two years, the same station maximum temperature difference is 2.72 °C, and is gradually increased since West to East and rose yearly; pH are maintained in 7.8~8.3, are partial alkaline and relative compared stable, then pH of enclosed sea are below offshore waters, which in pH interval of red tide easy outbreak, existing high risk. DO concentration are between 6.3~7.7mg/L, does not have the foundation of extensive outbreak red tides. Lower percentage of DO in enclosed sea and with less material flux in offshore waters, so enclosed sea are high-incidence areas. Chlorophyll concentration in 2013 are almost lower than 2011, and smaller fluctuations. The environmental capacity of the waters in the Beibu Gulf is getting saturated; therefore, it should closely monitor water temperature, pH, and DO and chlorophyll concentration for predicting red tide.

In this paper a novel filter structure which can be used to find the zero point of the sensorless back-emf of BLDC is proposed. The back-emf amplifier circuit applied this structure is a kind of analog and digital mixed type. It can improved sensorless performance under low speed situation greatly. At last the production and experiments were carried out based on the 100W BLDC driver system. The applicability of the proposed structure was also verified

A three-factor-three-level experiment was developed by the central composite design (CCD) and Response surface methodology to discuss the effects of concentration of K2CO3, activation temperature and time on the adsorption capacity of the activated carbon (AC) derived from the rice husk and to identify the key preparation parameters. The performance of the AC was characterized by nitrogen adsorption isotherm as Brunauer–Emmett–Teller (BET) and scanning electron microscope (SEM), respectively. The optimal parameters were obtained: Rice husk was soaked in K2CO3 solution (2.32 mol/L) with an impregnation ratio (rice husk: K2CO3=1:3) (wt. %), activated at 1239 K for 0.48 h. The results showed that iodine adsorption capacity of the AC was 1268.52 mg/g, the error between the models predicted (1356.98 mg/g) was only 6.2%. The AC has a large apparent surface area (SBET = 1312 m2/g), total pore volume (0.78 cm3/g) and average pore diameter (11.92 Å).

A novel photochromic diarylethene bearing a pyrimidine moiety, 1-(2,4-dimethoxyl-5-pyrimidinyl)-2-[2-methyl-5-(3-cyano)-3-thieny-l] perfluorocyclopentene has been synthesized. Its properties, including photochromic behavior and fluorescent properties, have been investigated. The compound exhibited remarkable photochromism, changing from colorless to blue after irradiation with UV light. The results indicated that the pyrimidine moiety played a very important role during the process of photoisomerization reactions.

In this paper, we introduce an effective iterative method to solve the thermal linear system in HotSpot thermal floorplan, the iterative Conjugate Gradient Method is suitable to solve the traditional sparse matrix linear equations. We define a class of dummy sparse linear systems in iterative thermal floorplan algorithm, the iterative methods for linear system can be extended to apply to other iterative framework algorithm. We apply the conjugate gradient method to solve the thermal model in floorplan of VLSI physical design. The experiments' result shows that thermal floorplan using Conjugate gradient method is effective. The running time of our incremental conjugate gradient thermal solver with Jocabi Precondition is approximate 0.59 comparing with LU decomposition method.

A facile one-step method of growing nickel/iron layered double hydroxide (Ni/Fe-LDH) films with nanosheet structures on Ti sheet is presented and the electrochemical performance is investigated. Cyclic voltammogram of Ni/Fe-LDH electrode shows a pair of well-defined redox peaks at-0.4~-1.4 V, which is quite different with the previous reports on LDHs used for supercapacitors. This result implies the Ni/Fe-LDH may be an alternative for the cathode of the asymmetric supercapacitors.

The paper analyzes the two kinds magnetic field sensor measuring principle based nuclear Zeeman effect, the signal characteristics are analyzed according to the formula of the sensor output signal, the curve of the sensor maximum output signal VS the earth magnetic field obtained by using the method of combination numerical and experimental. With constant output signal amplitude as a criterion, the amplifier which satisfies the characteristic of the sensor output was designed. To further improve the SNR, program controllable self-tracking band pass filter (PCSTBF) was designed based on the switch capacitor filter and the FFT. The results showed that: the SNR was increased by using the amplifier which contains the PCSTBF, and the bandwidth of the output signal was not reduced.

Hypereutectic Al-Si alloys have low thermal expansion coefficients, excellent wear resistance, and high hardness. To replace cast iron with hypereutectic Al-Si alloys, the hypereutectic Al-Si alloys must still have the originally desired mechanical properties. The addition of Fe and Mn to the hypereutectic Al-Si alloys can form Fe-rich phases, which can improve thermal stability. In this paper, the effect of manganese (0 %, 0.99 %, and 1.36 %) on the Fe-rich phases of hypereutectic Al-22Si-2Fe (% w/w) alloys was studied. The results showed that primary Si particles (PSPs), needle-like Fe phases, a coarser fishbone-shaped α-Al15(Fe, Mn)3Si2 phases, and eutectic Si could be refined by cooling slope. With such a CS process, the intermetallic compounds in the alloys with different Mn/Fe ratios were examined with an optical microscope, scanning electron microscope, and X-ray diffraction. Moreover, the blocky α-Al15(Fe, Mn)3Si2 phases were analyzed by transmission electron microscopy. Through the analysis of the SADP, the lattice structures of α-Al15(Fe, Mn)3Si2 phases were identified with tetragonal structure and body centre cubic.

It is an inevitable result of the education informationization for middle school students to carry out network learning. In order to obtain good network study effect, media preference study of middle school students is very necessary. Media preference refers to students’ fond degree of media in learning network resources. From media preference, students’ personality characteristics of media can be better understood to help network system choose more suitable teaching method for high school students. This paper, by using Fuzzy C Means clustering algorithm, studied media preferences, and got reasonable results, thus provides personalized learning basis for network resources.With the development of information technology, network distance education is developing rapidly as a new means of education and way of education. However, most of the network resources learning rely mainly on students' autonomous learning, and did not provide good personalized learning style and environment. Media preference degree is an important basis of personalized teaching, so how to carry on reasonable analysis on media preference is very important. Students’ media preference behaviors are stored in network background. By using FCM (Fuzzy C Means clustering algorithm), reasonable analysis for media preference can be done. The analysis of the results can be used as the basis of personalized learning to better promote personalized online learning.

In this article, the author uses computer graphics visual programming method and visually expresses ionospheric characteristic parameters. Firstly, the significance of visualization of ionospheric characteristic parameters was described, then visualization process and methods were discussed, and finally the results of visualization of ionospheric parameters in typical conditions were given. The results show that visualization method of ionosphere characteristic parameters can directly reflect ionospheric electron density, electron temperature and other parameters, which is conductive to an intuitive understanding of various physical phenomena in ionosphere.

How to treat dredged sediment is one of the main environmental problems and the recycling technique is the best way to deal with this problem. This paper deals with the feasibility of beach protection project alternative materials-dredged sand, applies cement and addition to solidify it. The components of dredged sediment and the physical properties were analyzed. Specimens with a designed mix ratio of the cement and dredged sediment were made by means of instant formation. The specimens were cured under standard condition and room temperature. The unconfined compressive strength of specimens were measured after curing for 7, 14 and 28 days. Using solidified dredged sediment as construction material has advantages of technology, economy and environment protection.

The modified adsorbent was modified by amine reaction with brewer's grains that using epichlorohydrin as etherfying agent,N,N-Dimethyl formamide as dissolvent, triethylenete tramine as cross-linking agent.The simulation of Cr (VI) wastewater as treatment object, through the optimization of synthesis conditions of Cr (VI), the optimal synthesis process was obtained.The results showed, 4 g brewer's grains, add 15 ml epichlorohydrin and 15 ml N,N-Dimethyl formamide stirring 1h at 85 °C. Then added dropwise to 4mL triethylenete tramine, mixing reaction 1h at 85 °C. The maximal absorption rate got 99.81%.The modified brewer's grains of amine surfactant modified is a promising treatment of chromium wastewater biological materials.

In this paper, a new method for preparing semi-solid Al-25%Si alloy slurry named as Rotating-Rod Induced Nucleation (RRIN) was adopted. In this method, liquid metal (velocity 0.66 kg/s) flew toward a vertical stainless steel rod (45 mm in diameter) which was self-revolving on its axis. Molten alloy was spread around the rod surface under the effect of rotating, which caused supercooling and induced nucleation of primary Si in the molten metal. After spread around the rod, molten alloy flew off the rod and down to a graphite crucible. The influence of rotating speed on the microstructures in the semi-solid slurry was studied. The refining mechanism of primary Si was also analyzed according to the change of the spreading state, the number of primary Si particles (PSPs) in per unit area (N), and the distribution of PSPs size under a series of different rotating speeds (from 100 r/min to 1000 r/min, and at intervals of 100 r/min). The results showed that, under the lower rotating speeds such as 100 and 200 r/min, the molten alloy flew downward along the rod. With the rotating speed increasing, a molten alloy film around the rod was formed under the effect of the tangential force caused by the rotating rod, and the film thickness thinning, the spreading area and the N was increased. The uniform supercooling in the whole molten metal film was obtained under the condition of higher rotating speeds such as 500 and 600 r/min, which promoted nucleation of the PSPs significantly. It is called Rotating-Rod Induced Nucleation (RRIN). After spreading around the rod during short time, the molten metal film was thrown away the rod rapidly under the effect of centrifugal force, which prevented further supercooling and growth of PSPs. Under the condition of too higher rotating speed of the rod such as up to 700 r/min, the molten melt flew off from the rod apparently before spreading around the rod surface, molten metal film as mentioned above was destroyed, RRIN was weakened. The microstructure with fine PSPs (27 μm) was distributed uniformly in the semi-solid slab obtained under the condition of rotating speed of 600 r/min and pouring temperature of 785 °C in this experiment. Keyword: high silicon aluminum alloy; Rotating-Rod Induced Nucleation; Si phase; refinement.

Orthogonal experiment optimization of microwave-assisted extraction (MAE) conditions of total flavonoids from castor leaves with the factors of ethanol concentration, microwave power, extraction time, solid/liquid ratio on the yield of total flavonoids were studied. The results showed that optimum extracting conditions of total flavonoids from castor leaves were as follows: adding 1:50 g·mL-1 of 40% alcohol and extracting for 3 min,microwave irradiation power 464W. Microwave extraction of total flavonoids from castor leaves is fast, energy saving and high extraction rate.

Softwares is becoming increasingly important causes for failures of safety programmable electronic (PE) systems,PRA and CSRM both take it as an important risk contributor and respectively access risk of systems and software in system level.However they partly identify software-related risk scenarios ,and can’t tell what a software must do about all safety-critical conditions,i.e.,safety functions,especially warning functions for conditions software can’t control but must alarm operators to action immediately.Here we give a method to find all software-related safety-critical scenarios,through it all safety-critical conditions and the corresponding functions can be identified.

In this study, the self-evolution problem of knowledgeable manufacturing systems is studied by taking an assembly workshop as an example. The rolling horizon procedure (RHP) is adopted to implement the self-evolution process of the workshop. The whole dynamic self-evolution process is decomposed into several static decision processes. At each decision point, a static decision sub-problem needs to be solved. A general mathematical model of these sub-problems is built, and a bi-level genetic algorithm (BiGA) is designed. Simulation results show that the model and algorithm are feasible and effective. By comparison, the system with self-evolution operations has a better production performance.

The kinetics of nitrogen absorption in Fe-Cr-Mn (Mo) alloys under 0.1 MPa nitrogen pressure and 1873K was investigated by top blowing nitrogen gas into the steel melts. A thermodynamic model of nitrogen solubility was established. Also the effect of surface active elements oxygen and sulfur on nitrogen absorption was studied. The results show that Fe-Cr-Mn (Mo) melts achieve nitrogen saturation value within 50 minutes, the nitrogen solubility increases with the content of chromium and manganese, but the experiment values of nitrogen solubility are general lower than theoretical values because of the open nitrogen gas atmosphere and high surface active elements content in the steel melts. The nitrogen absorption can be described well by a second order reaction and the interfacial reaction is restrictive step. The rate of nitrogen absorption decreases by lowering the surface reaction constant due to oxygen and sulfur in the steel melts. The effect of the surface active elements oxygen and sulfur on nitrogen absorption can be described well as .

A new cold rolled hot-dip galvanizing DP450 steel with low carbon and high chromium was designed and effect of the galvanizing processes on the microstructure and mechanical properties was also investigated. At last, it was compared with the referenced DP450 steel which was already produced in industry. The results show that microstructure of the experimental steel consists of regular polygonal ferrite, almost 1% MA island and little bainite. The industrial experimental cold-rolled galvanizing DP steel has excellent combined mechanical properties as follow: yield strength is 306 MPa, tensile strength is 467 MPa and elongation (A80) is 33%. Compared to the referenced steel, the experimental DP450 steel has lower yield strength, better elongation and better forming performance, accordingly.

23Co-Ni is an ultra-high strength steel and it needs ultra low nitrogen content in the steel. The removal of nitrogen for 23Co-Ni steel in a 6t/12t Vacuum Induction Melting Furnace (VIM) with different melting processes was studied. The results show that, the longer of the melting time and the higher of the vacuum level, the lower of the final nitrogen contents is. The denitrogenization rate can reach 70% when the melting time is more than 8 hours. The electromagnetic stirring can increase the denitrogenization speed. When the VIM is vacuumed to 1-3 Pa, it can make the nitrogen content reaches 0.0005%-0.0008%.

Orthogonal experiment optimization of adsorption conditions with the factors of pH value, adsorption time, adsorbent amount of brilliant cresyl blue wastewater by brewer's grains were studied. The results showed that optimum adsorption conditions were as follows: 100 mL brilliant cresyl blue dye solution of 150 mg·L-1,adding 5.0 g·L-1brewer's grains of 60~80 mesh and adsorbed for 2.0 h,extraction temperature 30°C,pH 5.0. Under the optimal conditions, the maximal absorption rate got 95.12%.The brewer's grains is a promising, cheap, efficient, new biological materials of adsorption for brilliant cresyl blue in wastewater.

With the rapid development of network technology, information systems processing capacity is growing. GIS technology is increasingly widely used to automate the management direction of the expansion in the coal mine management, and has been more widely used. Information management in the coal mine management for China's modernization drive has a very important significance. On the basis of the analysis the advantages and disadvantages of GIS technology the coal mine management system, this paper presents a reliable transmission technology and designs a mine management system GIS model and the transport layer feedback information in the mechanism is used to achieve the mine management system information application optimization.