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This paper designed and completed the different polymer dosage of recycled concrete, was prepared by adding amount was 7%, 14%, 21%, 14% styrene butadiene latex recycled concrete, recycled rubber powder recycled concrete and ordinary concrete block, the cube compressive strength and damping performance test. The cube compressive strength of concrete test according to the ordinary concrete mechanics performance test methods, specimen is 150×150×150 mm cube specimens, pressure testing machine loading speed is 0.5 MPa per second. The concrete damping performance test is carried out according to the free attenuation method, with the hammer vibration test device, the test piece is T type. Based on the damage form of specimens, the compressive strength and damping performance analysis, and compared with ordinary concrete as the benchmark analysis test results show that the polymer recycled concrete cube compressive strength failure process and failure pattern basic consistent with common concrete. In the water/cement ratio, sand ratio, and amount of material per unit volume is the same, under the condition of polymer recycled concrete cube compressive strength is lower than normal concrete, damping performance is higher than that of ordinary concrete, the compressive strength is inversely proportional to the damping sexual relations.

The characterization of phosphoproteins requires highly specific methods for the separation and enrichment of phosphopeptides. Here we report a novel metal ion-immobilized solid phase material for the separation and enrichment of phosphopeptides. The material is uranyl-salophen-silica gel (USSG) particles in which salophen is a tetradentate ligand of uranyl ion. In USSG salophen is connected on the surface of silica gel and uranyl is bound on the surface through its coordination with salophen. Phosphopeptides can be selectively retained by USSG because uranyl-salophen can bind phosphate moiety with strong affinity and high selectivity. The new material USSG has been successfully used for the separation of phosphopeptides from peptide mixtures with the separation efficiency of 97.0% to 97.4%.

The avionics system is a core component of the civil aircraft. To reduce the risk and cost of developing avionics system, shorten the development cycle, through the development process of avionics systems, variety of simulation and verification must be done. The bus excitation signals need to be provided for each avionics unit and the signals from each avionics unit need to be received and processed. The multilayer abstract model and organizational structure model of the bus excitation system was established. And a complete bus excitation system was designed. In this system, the ARINC429 bus signals and discrete signals for communication and navigation equipments were provided, and the signals from the equipments were received and processed. This system has been tested, and one practical application example of the system was given.

Combined with the Beijing Business Center (CBD) core district Z14 plots commercial finance project (hereinafter referred to as the "CBD project") foundation pit construction, introduces the deep foundation pit of bored pile reinforcement cage fabrication and erection construction technology. In the construction process, through the site set up a special steel processing and production platform, the localization of the flange and other measures to solve the steel reinforcement cage positioning and connection construction difficulties. Combining the engineering fact, detailed calculation process of lifting steel cage hanging position, lifting machinery and hoisting rigging selection, and through the ANSYS software of finite element analysis and put forward specific measures to ensure the quality of steel reinforcement cage.

Shaking leaves has been the biggest interference for early forest smoke video detection. Moving average method, Gaussian mixture method and its improved methods are often used to update background, but the performance is not good through background subtraction. Codebook algorithm is applied to extract foreground for early forest smoke detection, quantization techniques are used to obtain background model from time series, then getting foreground image through background subtraction. Through multiple video tests, the experimental results that the filtering performance, anti-noise performance and accuracy are better than other methods above.

Based on theoretical deduction, according to the characteristics of nuclear power unit, a universal heat economic framework for PWR nuclear power plant heat regenerative system was established. And on this basis, the cycle thermal efficiency was chosen as the optimization goal, the extraction steam pressures were chosen as optimization variables, a universal nuclear power unit regenerative system optimization model was established. A 900 MW nuclear power unit was taken for example, it’s the first time that AWPSO was applied to optimize the regenerative heat system of nuclear power unit. The result shows that the convergence ability and search performance of PSO are superior to other methods and the original design scheme. A new and convenient design is provided for PWR nuclear power plant heat regenerative system in this paper.

In order to develop new Al alloy, the quasi-static and dynamic compression deformation behavior of an advanced Al-Mg alloy, which contained Zn and rare earth, were investigated. Deformed microstructures in the shear bands of this alloy were characterized by optical microscope. Results show that the compressive strengths increase with strain and strain rates being increased, and microstructures of deformed Al-Mg alloy along compression directions are sensitive to strain rates. The distorted deformation twins near the deformed band can be formed under low strain rate of 5.6×10-3 s-1, while multiple shear bands slipping can be induced by dynamic deformation under high strain rates from 1.9×103 s-1 to 5×103 s-1. Therefore, compressive strength and fracture strain of dynamic deformation are higher than that of the quasi-static deformation, which is attributed to the strain hardening and grain refining in the multiple shear bands.

This paper presents intensity calculation of the cylinder block of the underwater instrument cabin which has outer diameter of 220mm, thickness of 7.5mm, and length of 1660mm. With simplifying force of the cylinder block to the problem of elastic plane stress, its’ internal stress is calculated under internal pressure and external pressure, in the case of the simulation tests and working state. Calculations and simulation indicate that: its’ maximum internal stress exceeds the elastic yield limit at 30MPa, and the cylinder block cannot work in 3000 meters underwater. At the same time, it proves that the maximum internal stress first starts from the inwall of the cylinder block with the method of using internal pressurization test, which is consistent with the working state, but because the maximum internal stress in the test state is less than the maximum internal stress in the working state, the test method may misjudge. Finally, through calculation, it is specified that the theoretical work water depth of the cylinder block is 1300 m and the axial deformation is about 0.5 mm, radial deformation is about 0.1mm, which provides reference for the seal design.

The pit corrosion behavior of steel rebar in alkaline chloride solutions without and with EMISE ionic liquids inhibitor were investigated by means of electrochemical noise (EN). The experimental results of electrochemical noise measurement revealed that the pit corrosion was inhibited and corrosion pitting process was retarded significantly. The mechanism of the inhibition effect of the inhibitor was analyzed based upon the combined stochastic theory and shot noise theory using the Weibull distribution and Gumbel distribution function.

The problem of the non-probabilistic reliability is investigated in this paper, in which the convex model is used to deal with uncertainties in structural analysis and design. The limitation on the current non-probabilistic reliability is discussed. Then a novel non-probabilistic reliability model is proposed, and its computational procedure is given. Two numerical examples are conducted to illustrate the feasibility and validity of the proposed non-probabilistic reliability model.

In this paper, PLC and configuration technology has been applied to the variable speed hydraulic technology. So in the future, monitoring system of variable speed hydraulic technology has been widely used. This thesis of variable speed hydraulic test stand uses PLC as the controller and the century star configuration software as the control software. According to the characteristics of variable speed hydraulic test bench and monitoring system, the monitoring system hardware and software are analyzed in detail. A set of variable speed hydraulic test station monitoring system has been designed.

In rare strong earthquakes, the steel structure may occur the nonlinear behavior and redistribution of internal forces. In order to understand the post-buckling behavior of steel structures and determine the weak areas of the structure, and then determine whether the structure under strong earthquakes meets the seismic design goal or not, this paper adopts the FNA method to analyze the response of large profiled steel structure under severe earthquakes. Finally, we draw some general conclusions which are valuable for designing the large profiled structure.

In this paper a algorithm of digital image watermark based on wavelet bit plane is introduced, and the original image is not required for detecting the watermarking. The digital watermark is embedded by changing information of some bit planes in DWT images at different resolutions. The watermark can be extracted on the difference bit plane values of subimages of the decomposed watermarked image which is then mapped to an image with a few shades of gray. Experimental results show that the watermark is robust to several signal processing techniques, including JPEG compression and some image processing operations

The Multi-signal Flow Graph (MFG) is a simple and effective system modeling methodology, widely used in testability analysis and fault diagnosis field. In order to shorten the maintenance time and reduce the influence of human factors, the MFG method was introduced, and it was used to set up the testability model of aircraft Audio Management Unit (AMU) and found the fault-testability dependency matrix and the fault-fault dependency matrix. Based on dependency matrix and real unit fault message, the trapezoidal fuzzy number algorithm was introduced, thus the new fault diagnosis method was generated. Finally, an example proves that the fault diagnosis algorithm can not only locate the fault more accurately, but also improve the maintenance efficiency.

Nowadays, it becomes a hot research topic for autonomous flight of Quadrotor in the complex environment and the realization of fully autonomous flight is still a big challenge. The path planning of unmanned aerial vehicle is a key problem for its autonomous flight. For the path planning of Quadrotor, using the quantum particle swarm optimization algorithm, and made a lot of simulation and actual flight experiments. The results of simulation and actual flight experiment show that the using of QPSO for the path planning of Quadrotor is able to obtain a satisfactory result.

According to a detailed study of the fault tree model of the flight control system about Boeing 777, a pre-program was established for the fault tree. The minimal cut sets of the treetops event was calculated by Fussell-Vesely algorithm. And the directed graph search process based on DFS and fault tree module searching method based on double DFLM was used to achieve modular decomposition of fault tree. Therefore, a better structure tree and better rules generate. Finally, it combines the fault tree fault model with the ARINC624 specification to achieve communication requirements between the central maintenance system and flight control system. The Boeing 777 maintenance model was realized.

There are many closed limestone mines in Fengshan county, Guangxi autonomous region, Southwest China. The geologic environment in the mining area had been destroyed during the mining period without carrying efficient environment governance and land restoration. In order to mitigate the potential geological hazard risk induced by the closed mines, one representative closed mine is chosen to carry out the research of risk analysis. In the paper, firstly, the mine is divided into different zones according to rock mass structure, and geological environmental problems have been analyzed in each zone. Secondly, the failure mode and risk level are analyzed and determined by comprehensive methods of stereographic projection, rigid limit equilibrium method and numerical simulation (by using FLAC3D and ROCKFALL software). Lastly, risk assessments for the closed mine geological environment are proposed. The analysis shows that the mining face can be divided into eight zones (number from I to VIII), which are mainly composed of intact rock, blocky rock, thick platy rock, karstified rock and rock block accumulation body. The major risk in the area comes from rock collapses and rock falls on the mining face. Most of rock collapse will occur in the zone I and II. Rock fall will occur in the zone I to zone Ⅵ. The highest risk will occur in the zone I, II and VIII.

In this paper, a health risk model was used to calculate and analyze the water quality monitoring data of the Yangtze River Basin from 2007 to 2009. The data analysis leads to a conclusion that hexavalent chromium is a major health risk factor of those drinking water sources in the Jiangsu section of the Yangtze River basin. Based on the health risk analysis, an environment strategy analysis model and the Dynamic Actor Network Analysis (DANA) software were used to study the optimal strategy on the risk management of chromium contamination of those drinking water sources in the Jiangsu Section of the Yangtze River basin.

In estuarine and coastal area, due to the colligated function of tide, runoff, wind and wave, suspended sediment profile in main flow direction varies from the inland river. Thus, combined with massive data sets from experiments in flume and observations in field, the study on the profile of concentration of suspended sediment are carried out in the thesis. Finally, 3D numerical model of turbulent sediment is established in estuarine and coastal area to carry out a simulation research on current and sediment movement in Yangtze River estuary.

Electrodeposition recovery of heavy metals in concentrated solution of wastewater treatment by complexation ultrafiltration was studied. In the study, cheap plategraphite electrode was applied in the traditional electric cell reactor. Current density and mass concentration of the electrodeposition for cupric and zinc recovery were discussed, and the optimal condition were determined. The results showed that the current efficiency of cupric and zinc recovery were more than 60%, and corresponding power consumptions were 11.5 kW·h/kg and 14.0 kW·h/kg, respectively.

Repetitive control (RC) has the ability to compensating periodical disturbance and it is an effective way to improve the output waveform of inverter loaded nonlinear load, but the dynamic response is slow. From the perspective of output impedance, state feedback control is used to configurate the pole of the system so that it can modify the ouput impedance characteristic of the system, increase the damp ratio and promote the dynamic performance of the system. The simulation results show that the proposed compound control strategy make the system has advantages of good output waveform and fast dynamic response.

For running deviation of strip and camber deviation, a tension model was established on the discussion of the dynamic equilibrium state under tension. The friction difference of strips sides or workpiece wedge causes plain rolling camber, meanwhile housings elasticity inequality or roll tilt leads to axial shifting and camber deviation. In the digital simulation, the tension-drawing model is necessary to realize tension self-adjusting, and in the production, tension increments can be calculated for adjusting the two sides gaps.

Siltation in the rivers downstream of sluices is serious in China, making the discharge capacity of rivers decrease obviously and threatening the flood control in upper rivers. Tidal wave deformation is one conclusive dynamic factor leading to siltation downstream of sluices in estuaries. Take SheYanghe estuary as an example, the hydrodynamic characteristics of tidal wave deformation and sediment characteristics change before and after the construction of sluice are analyzed.

Pinhole defects on light gauge aluminum foilwere classified by the morphology characteristics. According to the classification, the formation mechanism of pinhole defects was discussed and some control methods for the control of these pinholes were proposed. and the methods to prevent the pinhole were proposed.

The transmission tower with a big span in the freezing area is very sensitive to climate. When extreme weather approaches, the tower may collapse easily. The dynamic characteristics of transmission tower structure vary under different weather conditions. This paper, taking a 500kV long span tangent tower as the research subject, will demonstrate the dynamic characteristics of such structures when the weight of wires, the icing stiffness of tower structure and the thickness of ice are considered. The results show that icing has a great impact on the dynamic characteristics of the tower structure and it can not be neglected. When the ice is thick, the contribution of icing to the stiffness of the structure should be considered. This conclusion can provide a reference for the analysis and design of similar towers in high altitude area.

Electromagnetic radiation pollution and its protection has become one of the hot issues of urban development process. This paper analyzed the cause of natural and man-made electromagnetic environment pollution, pointed out the harm of public health and the city normal production and living order and the city sustainable development. This paper suggested that comprehensive treatment measures should be taken to solve the problem of electromagnetic environment pollution in cities including the reasonable planning and layout, the real powerful supervision, the advertisement and education, and the high level of protection technology. This plays an important role and realistic significance in building a harmonious urban electromagnetic environment.

A grid generation method for the three-dimensional arbitrary complex geometry of casting is introduced for the foundry simulation. The approach of a STL (STereo Lithography) model from CAD to a distance field is described in detail. The mesh generated by this approach is based on a fully threaded tree and refined at specific positions according to the distance field. This algorithm may make the mesh become fine at the surface and coarse inside. Several examples are provided to validate this algorithm.

In practical relational database, there are many tables that the values of their most fields have only two kinds and the values of the left fields are all discrete. For this kind of table, the paper presented a new logical storage structure utilizing binary field to compress the data volume and by making binary operations and SQL statements combined to realize the new database operations to enhance their executing efficiency. Experimental results showed that the new storage structure indeed greatly reduced the physical storage space and optimized the performance of the relational database.

Ba 1-x SrxTiO3(x=0.6 to 0.9 interval of 0.1) ceramics were developed by a BT sol-assisted sintering technology with a mixed-phase sintering from the mixture of BT and ST powders synthetized by a solid-state reaction method. The sintering behavior and dielectric properties of the ceramics were investigated. Results show that the sintering activity of the ceramics becomes worse and worse when increased the strontium content, and the sintering condition have a remarkable effect on the density of the ceramics. Dense ceramics were obtained when sintered at 1280°C for 8h with a relatively density of above 94%. The composition had a strong effect on the dielectric properties, while the sintering schedule had a little influence on the dielectric temperature spectrum of the BST ceramics. The Ba 1-x SrxTiO3(x=0.9) ceramic with dielectric constant～335, loss tangent～0.000625 at 1.85 GHz and 20°C, and good temperature stability of dielectric constant above the room temperature is attained.

Based on the mass flow measurement by tunable diode laser absorption spectroscopy (TDLAS), the process of air flow measurement was modeled and simulated. Using the Gridgen software, we drew the model inlet grid. And we used fluid calculation program to calculate gas condition in the inlet model. Under the set conditions, we got the mass flow of the model. Compared the mass flow which is measured by the TDLAS technology with the calculated data, we can obtain the measurement accuracy of TDLAS.

In low-middle temperature porous geothermal field, precipitation of carbonate from solution to form carbonate scale is confirmed as the main obstacle to efficient reinjection from the used hot fluids in Xianyang city, NW China. The carbonate deposits cause operational problems and may even clog pipeline and reinjection drillholes. For this reason, it's important to understand how impact of carbonate precipitation on the second-hand geothermal water before reinjection has been operated, which concern sustainable utilization of the geothermal water in Xianyang, the famous porous geothermal field in China. In this paper, firstly, different possible minerals precipitation from used geothermal fluid were discussed, and carbonate scaling was regarded as mineral for chemical clog by using combined with lab and chemical simulation method. Secondly, the key impacts of carbonate scaling on clog in reinjection holes such as temperature, degassing, pH, mixing, mineralization were demonstrated based on coupled simulation both in lab experiment and theoretical method. Lastly, the distribution of carbonate scaling and its degree in study area were calculated. The results show that, as the main mineral for precipitation, carbonate exist in most thermal-water wells of study area with the minor or medium scaling, and the carbonate scaling vary increasingly from bottom to top in a single reinjection drillhole, north to south in the study area. According to mineral-dissolution-precipitation equilibrium calculation carbonate saturated tend growth with the temperature and pH increases in study area. The influence of mineralization on carbonate clog is different, common-ion effect in the south of study area is given priority, but in the north salt effect is showed main effect. The analysis for impacts on carbonate clog reflect that carbonate deposit effect are very complicated, which interact each other.

The flow regimes included low velocity non-Darcy flow, Darcy flow, inertia flow, and turbulence in some porous media. In abnormal high pressure gas reservoir, the flow velocity was higher than conventional reservoir. Due to turbulence flow, there would be unique flow characteristics in these reservoirs. The deliverability equation of gas well should be expressed by cubic term, containing Darcy term, Visco-Inertial term and turbulence term, instead of Forchheimer’s quadratic equation. The turbulence coefficient, the main parameter in the cubic term, was directly related to the absolute open flow. So far, there is no method to obtain this parameter based on gas field data. Also there is no acceptable correlation for the turbulence coefficient applicable to field conditions. An empirical correlation was established using multiple linear regression method to determine the turbulence coefficient through the Ka Lasu’s well test data. We also calculated the parameters for the other well in this field. The results show that this correlation is more accurate and more useful than the formula established by Ezevdembah on basis of the core data in laboratory.

Energy control (i. e. pressure control) has an obvious effect on development effect in the depletion of gas condensate reservoir. Phase change behavior and characteristics of the relative pemeability in gas condensate reservoirs were displayed in this paper, then pressure and condensate distribution were showed through reservoir simulation. Finally, the influence of the pressure drop on condensate distribution and condensate oil production in gas condensate reservoirs with different permeabilities was studied. Results show that: First, in high / moderate permeability gas condensate reservoirs, the pressure and the condensate blocking will extend to further reservoir, while the pressure and condensate just appear in the vicinity of wellbore in low permeability gas condensate reservoirs. Second, the influence of pressure drop on condensate distribution in high permeability gas condensate reservoirs is obvious, the condensate blocking extends with the increasing of the pressure drop, and condensate extent can be controlled by optimizing a rational pressure drop, while the influence is inconspicuous in low permeability gas condensate reservoirs. Third, the influence of pressure drop on condensate oil production in high / moderate permeability gas condensate reservoirs is conspicuous, a rational pressure drop exists, while the influence is indistinct in low permeability or tight gas condensate reservoirs, before the retrograde condensation, a low pressure drop should be adopted in a long term until the bottom hole flowing pressure drops below the dew point pressure, when the condensate blocking forms, well stimulation is advised before developing by pressure control.

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.

The paper establishes the ship-bridge collision early warning model on the basis of Fuzzy Theory and neural network method, puts forward the basic principles and concrete process of the ship-bridge collision early warning method. The model and calculation method applied in VTS after test and verification, it can achieve the practical accuracy and effect and finally achieve the active ship-bridge collision early warning.

In Gaoyao Region in Guangdong Province there are several gatherings of Eight-trigram form, which are extremely consistent with Eight-trigram pattern. Over the years, some scholars, as well as in the official publicity materials, hold that these gatherings are created based on the concept deriving from Taiji and Eight-trigram Thinking. However, after research on several typical Eight-trigram form gatherings, the author holds that the Eight-trigram form is only external manifestation of the gathering, it also has more important intrinsic causes. The first is the adaptability to natural factors, followed by defense considerations, and the third is the social organizational forms.

In order to investigate the supramolecular assembly and interfacial coordination of special amphiphile, two Schiff Base compounds with alkyl chains and different azobenzene substituted groups were designed and synthesized, and their supramolecular assembly and interfacial properties were investigated by spectral and morphological measurements. It was found that the Schiff base compounds can be spread on water surface to form stable monolayer. When on the Cu(II) ions subphase, an in situ coordination can occur for all ligands. In addition, for the coordination process of C16SB-Me-Azo with Cu(II), there are obvious spectral changes for the alkyl chains. For all process, the headgroups in all amphiphiles have predominant effect in regulating the aggregation mode and spectral changes in organized molecular films.

A series of Schiff bases derivatives with aromatic spacer have been designed and their interfacial phase behaviors and coordination with Cu(II) ions were investigated. It has been found that on the subphase containing Cu(II) ions, all of the Schiff bases can coordinate with Cu(II) in situ in the spreading films, especially for NSB-C16 with the obvious conformational change of alkyl chains. The in situ Cu(II)-coordinated films could be transferred onto solid substrates and subsequently characterized by various spectroscopic methods such as UV-vis and Fourier transform infrared spectra as well as the morphological characterization with atomic force microscopy measurement. Depending on the different groups, these amphiphiles showed different aggregation behaviors in the Langmuir-Blodgett films.

In this work, two functional azobenzene-containing metal complexes with different substituted groups have been synthesized and their photoisomerization have also been investigated. It has been found that depending on different substituted groups, the formed azobenzene derivatives showed different properties, indicating distinct regulation of molecular skeletons. Spectral data confirmed commonly the characteristic absorption of substituted groups and aromatic segments in molecular structures. Thermal analysis demonstrated that the structural influence of both compounds in different temperature ranges. The difference of thermal stability is mainly attributed to the formation of Schiff base group and different substituent groups in molecular structure. The photoisomerization of these compounds both in solution and in cast film can undergo trans-to-cis isomerization by UV light irradiation, depending on different substituted groups. The present results have demonstrated that the special properties of azobenzene derivatives can be effectively turned by modifying molecular structures of objective compounds with proper substituted groups, which show potential application in sensor and functional material field.

Nowadays the low-carbon economic development model is becoming more and more popular all over the world. The low-carbon economy requires the reduction of the consumption of high-carbon energy and the emission of greenhouse gas, and the combination of economic development and environmental protection. So the tourist spots should also conform to the trend and set low-carbon tourism as their goals that call for energy conservation and emission reduction to build up a good mode of economic circulation. Under this background, this essay explores to put forward a set of reasonable and concise evaluation indicator system. The system tries to fully reflect low-carbon levels of the tourist spots and find out the problems. What is more, the essay can provide a theory basis for the management and the implementation of policies.

Excessive vibration was observed from nitrogen reciprocating compressor buffer tanks and pipelines since the operation of this unit started in a coal chemical plant. Welding points had been frequently cracked on bolt buffer tanks, pipelines and bolts, which often led to a delivery failure of coal for subsequent reaction, causing great economic losses. In order to identify the root cause of vibration, a comprehensive analysis on the reciprocating compressor and pipeline system was conducted. The vibration has been kept within an acceptable range after the adjustment. The total production in the factory has been increased with effectively controlled cost and energy consumption. The probability of production system shutdown and accident is also significantly reduced.

Because of the separation of modified truck’s cab and car tank, there must set long wires to transmit the signal. A liquid level measuring device for truck is designed and developed in this article. Using the ZigBee technology, a wireless data transmit mode, including the hardware and the software, is realized. A compensation and correction method is discussed on the basis of the ultrasonic transmission theory. This device has a simple structure, high precision, low cost, easy to install and so on.

A new fluorescent probe, quinoline derivative DPQ bearing a methyl pyrrolidine-1-carbodithioate group, was synthesized and characterized by IR, Tof-MS and NMR. Its fluorescent behaviors toward transition metal ions were investigated. The results indicate that DPQ shows unique selective and high sensitive for Hg2+ in aqueous solution with a broad pH range 4-10. DPQ forms a 1:2 metal-ligand complex with Hg2+ ions with a limit of detection as low as 1.7×10-6 mol/L.

In this paper,we consider the oscillation of second order linear dynamic equation on time scales, and obtain sufficient condition for oscillation of solutions.

A novel colorimetric sensor based on BMPA derivative was designed and synthesized. The sensor displayed high selective and sensitive recognition of Cu2+in aqueous DMSO solution via an obvious color change from yellow to pink. The color change can be attribute to form a complex with Cu2+with C=O and N-H bonds. Based on this principle, an analytical method was developed and successfully used in the determination of the copper content in actual sample.

A rapid method based on high performance liquid chromatography-tandem mass spectrometry (HPLC/MS/MS) with accelerated solvent extraction (ASE) or solid phase extraction (SPE) was developed for quantitative determination of perfluorooctane sulfonate (PFOS) in the coatings of nonstick pot, food packaging materials, waterborne coatings containing fluoride and fire-fighting foams. The linear calibration curve was obtained in the range of 0.002 - 0.1 μg/mL with a linear correlation coefficient (R2) of 0.998 or 0.999. The recovery for PFOS was in the range of 93.4 - 103% with relative standard deviation of 0.48 - 3.59%. The detection limit for PFOS was 0.4 μg/m2 with a signal-to-noise ratio of 10 for the coatings of nonstick pot and the food packaging materials, and 0.0002% for waterborne coatings containing fluoride and fire-fighting foams, both of which meet the restriction requirement for PFOS content in these chemical materials and consumer products in the EU directives.

In this paper, we consider oscillation of solutions of the differential equations with variable coefficients on time scales, and obtain some sufficient conditions for oscillation of solutions.

Poly (phenylene sulfide) (PPS)/nano-ZnO composites were prepared by DAKA miniature blending instrument. Isothermal crystallization behavior of PPS composites at 245°C, 250°C, 255°C and 260°C were investigated by means of DSC. The crystallization time of PPS composites is shorter than which of neat PPS at the same crystallization temperature. The Avrami equation was used to analyze DSC data. Results showed that neat PPS is homogeneous nucleation at lower crystallization temperature, which is heterogeneous nucleation at higher crystallization temperature contrarily. PPS/nano-ZnO composites are heterogeneous nucleation at various crystallization temperature, nano-ZnO particles play a role of nucleating agent.

With flying development of computer technology and network techniques, computer simulation technology has become an essential measure to analyze, test and evaluate complex systems. This paper briefly introduces two methods of computer simulation modeling. It mainly focuses on six computer simulation modeling platforms including their development institutions, design ideas, basic features and addresses to download. Finally it summarizes the similarities and differences of the six platforms.

In this paper, we consider the non-oscillatory problems of odd-dimensional system of linear delay functional differential equations. Based upon the corresponding characteristic equations, we get some criteria for non-oscillatory solutions by utilizing the matrix measures.