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Under the pulse current, the lateral electromagnetic force on the shaped charge jet in the passive electromagnetic protective device is analyzed. Based on the equivalent circuit model, the current distribution model of metal plate is established according to the characteristic of current distribution proposed by Hummer. The lateral transient action model of a shaped charge jet is established based on the Biot Savart law. It is discussed in detail that the magnetic induction By of the shaped charge jet between two metal plates and the lateral electromagnetic force fx on the shaped charge jet varies with time and location. By shows U distribution along the jet axial. Before the 37μs, fx along the jet axial basically is M distribution; the maximum electromagnetic force appears in the distance near the site of the metal plates. After the 37μs, the lateral electromagnetic force along the jet axial basically is U distribution. Prior to 25μs, the total electromagnetic force Fx on the jet is approximately linear increase. In 25μ to 60μs, Fx maintains at a high level. The simulation result is identical with P. Appelgren’s result of static electrically-exploded conductors experiment.

Tunable bandpass filters are generally preferred and are used extensively in the mobile communication systems. In this paper, a design of the RF MEMS tunable combline bandpass filter is proposed. Firstly, the theory of the RF MEMS tunable combline bandpass filter is presented. Secondly, a combline bandpass filter which have a tunable frequency range from 18GHz to 27GHz is designed and simulated by using the EDA simulation software. Its bandwidth is about 1GHz in the tunable frequency range. From the simulation results, the designed filter is not only compact and effortless to fabricate but also relatively superior in some aspects.

Study on influencing factors of rapid identification of drainage oil by conductivity method through experimental, discuss the influence of different operating conditions on the determination results. The effects of oil/water ratio, oscillation time, temperature, and oil type on conductivity were explored. Measured water conductivity of different kinds of oil, analysed the change of the conductivity and the best operating conditions were elected. The results showed that under the condition of normal temperature, shocked the mixture for 30s, the oil/water ratio was 4:1 and subsided for 15 minutes,the conductivity of drainage oil,frying oil and edible oil were 72.7 us/cm34.3us/cm12.5us/cm. The conductivity was largest and the testing results was most sensitive.

Fe3O4-RGO composite nano material was successfully made through magnetite’s deposition on graphene.The measurement of scanning electron microscope demonstrated that magnetite with spinel structure attached on the surface of the reduced grapheme oxide without any conglomeration.The XRD spectrum revealed a heterogeneous structure of various composite materials. Fe3O4-RGO nano-composites were used as a cathodic catalyst for single-chamber MFC treating phenol sewage experiment. The results indicated the output of the max power density was up to 0.283 W/m2, while the internal resistance of the cathode was 151.2 Ω, which suggests the suitability of Fe3O4-RGO nano-composites being as MFC’s cathodic catalyst.Both of phenol and glucose could be used as substrates for the generation of electricity in MFC. The output of the power was stable after a period of operation. Meanwhile, the concentration of phenol in the MFC decreased along with the extension of the operation time.

The Yellow River delta, as the last river delta to be developed, is an environmentally-sensitive area as well. At present, agriculture remains an important industry in the Yellow River delta, and it's of strategic importance to achieve sustainable development by developing ecological and circular agriculture in the region.

The microstructural evolution behavior of Mg-3Si-1.70Sn alloys during semisolid isothermal heat treatment was investigated by optical microscopy observations in the present study. With the holding time increasing, the grains evolve to be more spheroidal and 15min is adequate for the alloy to be spheroidized, after this coarsening begins to happen. The amount of the liquid islands inside α-Mg grains decreases and that of the liquid phase at the grain boundaries increases with the prolonged holding time. Moreover, the morphology of eutectic Mg2Si phases changes from the Chinese script and/or long-fiber shape to short fiber or spherical shapes during semisolid isothermal heat treatment, which can be attributed to the Rayleigh shape instability.

Radical copolymerization of styrene (St) and maleic anhydride (MA) were typically alternating copolymerization, which generated copolymer styrene-maleic anhydride (SMA). The copolymer was synthesized by solution polymerization method,with benzoyl peroxide (BPO) as initiator and xylene as solvent, and using the yield of copolymer as evaluation criteria, the reaction conditions were researched. The maleic anhydride of molar fraction was 45% in the copolymer measured by chemical titration, combined with the theoretical that the synthesis of styrene-maleic anhydride copolymer was confirmed to be the alternating copolymer. The structure and character of the copolymer was also confirmed by IR. The glass-transition temperature of the alternating copolymer was tested by DSC.

Whether the ecologically fragile areas can avoid weakness and enhance strong points and take advantages of their resources and carry on the reasonable development, it is related to the success or failure of the regional economic and social sustainable development strategy. Yellow River Delta as typical ecological fragile areas in China, the development of ecological and circulatory agriculture has strategic significance for the area towards the road of sustainable development. For the problem about Yellow River Delta develop ecological and circulatory agriculture, such as fragile ecological conditions, water shortages , serious environmental pollution, ecological technology relatively backward, low cultural quality of the agricultural labor force and weak support policies, we must take some countermeasures like development of rural education, promotion of ecotechnological progress, improvement of the agroecological environment , the comprehensive development and so on.

Fine polystyrene fibers have been generated from electrospinning of PS/molybdophosphoric acid in THF and DMF solution. The fiber diameters ranged from 500 nm and increased by adjusting the volume of DMF, the amount of the PS/ molybdophosphoric acid and spinning voltage, the size of the distance. Surface morphology of the nanofibers was characterized by scanning electron microscopy (SEM). The fibers generated from the solutions were more homogeneous in sizes, especially when more THF was added. With the phosphomolybdate amount of increase in untreated, cold pressing, hot pressing modulus showed a trend to decrease. The infrared results show that the composite membrane contains four phosphomolybdate absorption peaks, which is consistent with the predicted results.

The climate change issue and the real or potential substantial climate migration arising from climate change and its adverse impacts have become a severe challenge for human society in the 21st century, and one of the core concerns of human society today. Through the analysis of the climate migration phenomenon arising from various climate risks during the course of social development, and the conceptual definition and classification of climate migration, this paper aims to strengthen our understanding and perception of climate migration, and further grasp the essence and law of evolution of climate migration, so as to make a preliminary exploration into how to tackle the challenge of climate migration arising from climate change, mitigate social risks facing climate migration, and promote the benign operation and balanced development of society effectively.

To explore the effect of the electrical degradation of phenolic compounds with TiO2 under different conditions. The effects of pH, electrode distance, cell voltage, concentration of electrolyte Na2SO4 and the initial concentration of phenol were studied for the removal efficiency of phenol. The experiment measured that reacted for 60 min under the conditions that the original solution phenol content is 10 mg/l, the voltage is 15 V, the electrode distance is 1 cm, the electrolyte Na2SO4 is 0.2 mol/l, the removal efficiency of the phenol reached 99%.

This Thesis uses the deep clay in the land subsidence area in Xi’an city as the research object, carries out the indoor high-pressure rheological test to the deep clay, discovers the nonlinear model consistent to the rheological property of the deep clay, and conduct a preliminary discussion to model. This thesis has an important preference value and significant meaning to the research of the deformation mechanism of aquitard in this subsidence area Introduction.

In this study, a amphiphilic copolymer, poly ((N-isopropylacrylamide)-co-acrylamide-co- (octadecylacrylate)-co-(Falate-(polyethyleneglycol)-(acrylicacid)))(P(NIPA-co-AAm-co-ODA-co-FPA)) micelles was synthesized by free radical random copolymerization. The obtained amphiphilic copolymers were self-assembled into micelles, which exhibited thermally sensitivity. LCST of the micelles was detected by uv-vis spectrophotometer. The diameter and morphology of micelles were determined by laser particle size analyzer (LPSA) and transmittance electron microscope (TEM), respectively. The micelle with a diameter of 60 nm and LCST of 40 oC was obtained by utilizing of ODA and the feed ratio of NIPA and AAm, respectively, which is satisfied for drug delivery in living body. The maximum DLC was achieved with the amount of ODA (180mg).

Matriptase is a type II transmembrane serine protease highly expressed on the surface of tumor cells and participated in a range of human cancers including those of the breast, cervix, ovaries, prostate, colon and gastrointestinal tract. In this study, we developed a new matriptase detection probe with gold nanoparticles (AuNPs). A fluorescence dye was attached to AuNP surface through the bridge of peptide substrate (GRQSRAC). The fluorescence was quenched due to the fluorescence resonance energy transfer (FRET) between AuNP and the fluorescence dye. The fluorescence recovery properties were confirmed by dithiothreitol in vitro. The result of in vitro cell research indicates that the gold nanoparticle probe is sensitive and specificitive for the detection of matriptase expression in early tumor and has great potential in biomedical application.

With the quickening of the process of industrialization and urbanization, industry and urban water consumption rising increased the demand for agricultural water resource. Water pollution brought by industrialization and urbanization reduces the water supply. In the freshwater resources under the condition of the total supply shortage, Shandong agricultural water will face greater pressure. So various and effective measures must be taken to ease the contradiction between supply and demand of agricultural water resources.

The climate change issue and the real or potential substantial climate migration arising from climate change and its adverse impacts have become a severe challenge for human society in the 21st century, and one of the core concerns of human society today. Through the analysis of the climate migration mechanism during the course of social development, and the conceptual definition of climate migrants, this paper aims to strengthen our understanding and perception of climate migration, and further grasp the essence and law of evolution of climate migration, so as to make a preliminary exploration into how to tackle the challenge of climate migration arising from climate change, mitigate social risks facing climate migration, and promote the benign operation and balanced development of society effectively.

This article develops one new test technology, dumbbell test method, for evaluation of the early age cracking property of Concrete Material under constraint conditions. Its exercise of stress risers could lead concrete to crack quickly, providing a quick method to evaluate the early age crack performance of concrete material and to perform simulated test at job site conveniently. By this method, the anti-cracking performance of different concrete material can be evaluated quickly in the construction site.

Centrifuge model tests were conducted to investigate the behavior of cohesive soil foundations during a construction of an embankment, considering different dry densities and moisture contents of the soil. During the construction, the deformation of soil foundation gradually increased and reached the peak value at the top of the foundation near the center of embankment. After the embankment was completed, the deformation of the foundation continued increasing. The dry density and moisture content of the soil significantly affected the deformation process of the foundation.

This paper presented the results of centrifuge model tests conducted to investigate the behavior of cohesive soil slopes under the vertical surface load, considering the bolt-shotcrete supported slopes. The cement layer and bolts influenced the behavior of the slope when surface vertical load was applied. The analysis of bearing capacity and displacement threw light on the failure and displacement distribution of the slope.

In this paper a general numerical method to analyze some simple planar frames subjected to concentrated loads with elastic large deflection is presented. In the method some reactions or displacements at the ends of the frames with three or below redundant constraints are considered as unknown, and a numerical method based on a more-fold method of bisection is presented to solve for the unknown reactions or displacments under known boundary conditions. In the examples in the paper,the flow graphs of solving for unknown reactions or displacements are demonstrated and some analysical results are given by the aid of some graphics.These examples show that some simple frame structures with three or below redundant constraints can all be analyzed easily and quickly with the numerical method presented in the paper.

Under the operating load, the fabrication hydraulic torque converter could be regarded as a rotating pressure vessel. It will dilate like a balloon as a result of the centrifugal force and fluid pressure. The magnitude of deformation affects the performance of fabrication hydraulic torque converter and its connection with adjacent parts. Based on the three dimensional measuring machine and platform UG and Gambit, the frame model of ballooning deformation is established and simplified. Based on modern computational fluid dynamics theory, the simulation software FLUENT, MSC.Partran and MSC.Nastran are employed to make simulation prediction for the ballooning deformation. The results of the simulation are checked out through the experiments. The experimental results show that the calculation and experiment results are coherent. The increase of axial displacement has a linear relation with the rise of fluid pressure. The largest stress occurs near the intersect of the shell and working face. The largest strain takes place at the outlet of the pump and inlet of the turbine.

Using Xinxue River Constructed Wetland as the study object, the wetland prediction models based on BP neural network were established through the seasonal division of the wetland, and the maximum influent water load was determined on the constraint condition that effluent water quality achieved class Ⅲ of surface water quality. Then nonlinear functions of water quality and quantity scheduling were constructed by Origin software. The optimal influent load was determined adopting prediction results of the models as constraint conditions of the functions. Thus the water quality and quantity scheduling scheme of the wetland was established. The results show that optimal influent load for Feb. ~ May: the influent water quantity is no more than 8560m3/d, CODCr is 25.47mg/l~26.37mg/l, ammonia nitrogen 0.11mg/l~1.0mg/l, TN 10.28mg/l~10.51mg/l, TP 0.16mg/l; for Jun. ~ Sept.: the water quantity is no more than 31750m3/d, CODCr is 26mg/l~32.36mg/l, or 37.15mg/l~45.37mg/l, ammonia nitrogen 0.48 mg/l~1.78mg/l, TN 5.15mg/l~6.18mg/l, TP 0.07mg/l~0.09mg/l; for Oct. ~ Dec.: the water quantity is no more than 11070m3/d, CODCr is 24.55mg/l~26.91mg/l, ammonia nitrogen no more than 0.75, TN no more than 8.61 mg/l, TP 0.10mg/l~0.12mg/l, or 0.16mg/l~0.17mg/l.

Based on the monitoring data of February~December 2009 from Xinxue River Constructed Wetland, the regression analysis theory was used to establish mathematical models to determine the correlationship among the removal rate of pollutants, pollutant concentration, water temperature and influent water inflow, and optimize the operation parameters of the wetland. The multivariate linear regression equation was established with Statistical analysis software (SPSS). According to the correlation coefficient of the equation: the NH3-N removal has a significant positive correlation with water temperature, and a significant negative correlation with influent flow, total nitrogen removal has a significant positive correlation with water temperature, COD removal has a significant positive correlation with COD influent concentration. In addition, veracity of the model was also checked by contrasting the measured and analog data of March~June 2010 from the wetland. The results show that this model has a desired effect to estimate the removal rate and effluent concentration of COD and NH3-N, but undesirable to total nitrogen.

To evaluate the sustainable development level of construction in Shandong, China, the model was built by principal component analysis method. Meanwhile, Analytic Hierarchy Process (AHP) and basic rules of statistics were fully used to set up the index system. The data from 2007 to 2009 were processed by SPSS software, through calculation, the degree of sustainable development were shown intuitively.

Air defense radar target recognition is a difficult area of ​​target identification, target identification of aircraft has been an important area of ​​national military research. On the basis of jet engine modulation (JEM) effect of air craft, caused of rotating components’ periodic motion, an universal mathematical model of air defense radar propellers modulation echo is established in this paper. According to the characteristic of propellers modulation echo, simulated and compared the effects of propellers structure parameters to rotary blades radar echo signals, and pointed out that diverse types of the plane echo have different characteristics of modulation cycle. Compared the estimation performances of several features analysis and extraction algorithm with the study of prop-airplane echo signal. The simulation results demonstrate that the feature is stable and effective, bispectrum estimation value is more accurate and less errors. It’s feasible to using the feature to identify diverse types (or models) aircrafts.

This paper measured the vibration transmissibility of several honeycomb paperboards and the attenuation coefficient. Laboratory was used to determine the natural frequency of the thickness of 10mm, 20mm, 30mm, 40mm Honeycomb Paperboard. The test results show that the honeycomb paperboard resonance frequency decreases with increasing thickness, while the vibration transmissibility increases with increasing thickness. We have also established finite element model of honeycomb paperboard to simulate its vibration properties. The result of simulation is in good coincidence with the experimental result. In addition, some cases can use computer simulation instead of laboratory testing to obtain the natural frequencies of honeycomb paperboard.

The subtype of avian leukosis virus (ALV) was mainly determined by the gp85 glycoprotein. A subtype J ALV strain SCDY1 associated with hemangioma was isolated from grandparent breeding chicken and the highly antigenic region of its gp85 gene was amplified and expressed in Rosetta Escherichia coli using the pET-32a(+)vector. The fusion protein, which was expressed at a high level, was similar antigenically to the native gp85 protein as determined by Western blot assay using polyclonal antibodies against ALV-J strain. The fusion protein was also purified. This research lays a foundation for using this recombinant protein for development of indirect enzyme-linked immunosorbent assay (ELISA) for serum antibody detection or for production of monoclonal antibodies against prevalent ALV-J.

A field Marek’s disease virus (MDV), named as BY strain, was firstly isolated from Tibetan chickens in Sichuan province, China, by method of co-cultivation of the lymphocytes with duck embryo fibroblasts (DEF). Analysis of the oncogenic genes showed that there were 2 copies of 132-bp repeated sequence in long terminal repeat of the BY strain, The nucleotide and amino acid sequence identities of Meq gene of BY strain with other prevalent MDV strains in China were 97.6-100.0% and 98.8-100.0%, respectively, and some point mutations assumed to be relevant to the oncogenecity of MDV also existed in the Meq gene of BY strain. The result of animal challenge test on specific-pathogen-free (SPF) chickens showed lymphomas may occur in a variety of organs as early as 18 days post challenge, and the rate of tumor occurrences and mortalities reached to 73.33% and 66.67% in HVT immunized chickens, respectively. In conclusion, an MDV strain charac-terized of acute oncogenicity was isolated from Tibetan chickens in China, though there were no obvious difference between the oncogenic genes of this strain and other virulent MDV strains isolated in China in recent years.

The residual stress fields can have strong influences on the integrity and performance of friction stir welded aluminum alloy structure, comprehensive insight into the residual stress distribution is the key to the Friction stir welding (FSW) engineering application for a wide range of materials and thicknesses improving the weld strength and fatigue life. In this paper, the current state of the residual stresses in the FSW aluminum alloy joints is reviewed, The focus is on recent advances of experimental research, the results of numerical simulation analysis, and the effects of the technological parameters(welding speed, rotational speed, shoulder geometry et al.) on residual stress fields was evaluated. In the end, The controlling technique of residual stresses from published literatures is summarized.

We reported the preparation and electrochemical properties of fluorinated mesoporous carbon foams (F-MCFs) for application as electric double-layer capacitors (EDLCs). By using fluorinated resol which was obtained from the polymerization of formaldehyde, phenol, and 3-fluorophenol as the carbon source and fluorin precursor, and triblock copolymer F127 as a template, F-MCFs were prepared through evaporation induced self-assembly strategy. The F-MCFs were characterized by N2 adsorption and desorption, transmission electron microscopy (TEM) and small-angle X-ray scattering (SAXS). The results indicate that the F-MCFs possess highly ordered mesostructure with a specific surface area of 675 m2/g, a uniform pore size of 2.2 nm and a pore volume of 0.12 cm3/g. The wettability of F-MCFs was investigated by contact angle analysis. The contact angle of F-MCFs for water is 111.5o, much lower than that of mesoporous carbon foams (MCFs) (141o), indicating that the surface wettability of F-MCFs is improved by the introduction of fluorin into the carbon matrix. The enhancement of wettability would increase the surface contact of electrolyte and electrode and accelerate the ion transfer within the pore channel, and thus improve the electrochemical properties of F-MCFs. The electrochemical properties of the F-MCFs have been investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge in electrolyte of 6 mol/L KOH with a three-electrode system. F-MCFs present linear galvanostatic charge-discharge curve at a loading current of 10 mA, and possess good charge-discharge efficiency over 98%. The specific capacitance of the F-MCFs is 220 F/g, significantly higher than that of the MCFs (140 F/g). F-MCFs show important prospect as electrode materials for the application in EDLCs.

The temperature field of blast furnace tap hole clay was analyzed by using ABAQUS software. Samples taken from the tap-hole clay in depth of 1200mm, 2200mm, 2600mm and 2800mm after roasted for 100 minutes were studied by using XRD and SEM to investigate their roast mechanism and microstructure at different temperatures. The results show that the ore phase of the tap-hole clay in depth of 1200mm remained unchanged but only tar and asphalt appear the carbonation phenomena. There is a large number of SiC crystalline phase appears in depth of 2200mm. At the same time, porosity increases and coke structure is formed. The air permeability is enhanced. In the tap-hole clay of 2600mm～2800mm depth, elongated rod-likeβ-Si3N4 grains obviously increase while the SiC grains decrease. A large number of high-temperature flocculent mullite phase appears and the high-temperature strength of the tap-hole clay is strengthened.

In the paper, the housing of a specific type of sheet-metal type hydraulic torque converter is modeled and simplified by means of three coordinate measuring instrument and UG software. Moreover, the housing fatigue life is simulated and predicted by FLUENT and MSC software platform according to the three-dimensional flow theory. Further tests are launched to research and analyze the fatigue life and testify the simulation. It is proved that the simulation result basically complies with the experiment result. Upon less than 100,000 pressure circulations, the dilatation undergoes linear variations. In this phase, the housing suffers from elastic deformation. When the number of pressure circulation exceeds 100,000, the housing undergoes plastic deformation. Besides, the part of impeller and turbo housing with the largest curvature discontinuity, and the connection between the center and the bearing bushing shall bear a short service life.

In order to solve the problem that human objects in complex environments would be affected by illumination, deformation, moving, etc, a multi-feature information fusion based video tracking approach was proposed. In a particle filter framework, both the face color information and the head contour cue were fused effectively.This method overcomed the instability brought by using a single measurement source, and improved the tracking accuracy and reliability. Experiments on real video sequences demonstrate that in the same case our approach has more reliable performance than trackers utilizing only color or contour information with particle filter.

This paper constructs a common data fusion framework of fault diagnosis, by combining local neural networks with dempster-shafer (D-S) evidential theory. The RBF neural network is proposed as a local neural network of the fault pattern recognition, and its input vectors are extracted by the wavelet packet decomposition of various frequency energy. Then, the signal of each sensor separately has a feature level fusion. This method is effective, verified by experiments. The given decision level fusion is based on combining the features of the neural network and the D-S theory, and experiments show the results of the fault diagnosis are more accurate by this method.

Aimed at the problem of low accuracy rate for face recognition and speaker recognition in noisy environment, a multi-biometric model fusing face features and speech features is presented by combining Normalization and SVM theory based on the research of feature level fusion. Face features and speech features are first extracted by pulse coupled neural network and VQ-SVM respectively. Then the distance between tested people and template people is calculated after getting the fused feature on the feature level fusion. In order to reduce the computational cost and improve the recognition performance, matching distance is normalized and finally recognized by SVM. Experiment on the ORL database show that even when the signal to noise ratio is declined, recognition rate of the fused system is clearly higher than the single system under noisy environment and the purpose of identity recognition is achieved.

Active contour model is an important research field in computer vision and many researchers studied the variational method in recent years. The traditional snake model is unable to converge to the concave area and it has a lower convergence. By improving the external energy, researchers introduced a gradient vector flow active contour model (GVFsnake). Several standard images are used to segmenting experiments, and the results show that GVF has obvious advantages compared with traditional snake model in the iteration number of force field. Experiments show that the method is faster and better to converge in the concave area. The edge information can be kept well and diffused more quickly.

Phosphorus slag could be used to prepare wollastonite glass ceramics. With the aid of incorporated foaming agent, foam glass ceramics can be obtained via the sintering of the slag-based glass. After the glass powder reacted with graphite, macro-size pores with homogeneous distribution were formed. The level of porosity of the fabricated foams was controlled by varying heat treatment temperature and amount of foaming agent. It was found that the preferential processing parameters for producing foam glass ceramics were foaming temperature of 1000°C with holding time of 10 min and 1 wt. % of graphite. In this case, the porosity reached about 80%. The results show that dominant crystalline phase is wollastonite, and the high compression strength results from the crystallization of glass during sintering process.

Four methods were used to determine SiC content of self-combined 95 silicon-carbide brick, such as hydrofluoric acid volatilization-gravimetric method, direct method, etc. Results of different methods were compared, and causes of the difference were identified. The test results indicate that impurities compositions have different effects on different test methods. When impurities are free carbon, free silica, iron oxide, silicon oxide, hydrofluoric acid volatilization-gravimetric method is appropriate. When hydrochloric acid-resist impurities are more, it is necessary to choose direct and indirect methods. When using direct method and indirect methods, it is useful to increase the amount of flux to make sure that the specimen is dissolved thoroughly. If necessary, increasing test times is useful.