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Exhaust passage is a significant part of the gasoline engine, its structure will affects the gas flow characteristics of the engine directly [1]. So, research and analysis of the exhaust tract is essential. In this paper, a detailed analysis of the flow field under cold state and hot state was made. For a start, the method of laser scanning and UG software were used to reverse modeling engine exhaust port and get the three-dimensional model. The next, the unstructured grid with local mesh refinement scheme was used to mesh this three-dimensional model with ICEM. After this, numerical simulations of the exhaust passage with five different valve lifts were carried out under thermal and cold conditions. Finally, comparing the velocity field and pressure field of the exhaust passage under cold state and thermal state, it can be find that the flow field under hot and cold state have similar characteristics. The results of this paper can provide a theoretical basis for following researches of the engine exhaust port.

Engine intake system is one of the important parts of the engine which affects the engine’s volume efficiency and the uniformity of air entering to each cylinder directly Wherein the intake manifold with variable length is the important part of the intake system , has great significance value to research. Due to the structure of the manifold is complex, considering the manifold structure which affects the simulation accuracy, the principle of reverse engineering was used in this paper. Firstly, the laser scanning technology was used to obtain the point cloud data of the intake manifold.And then the cloud data was dealed by software Geomagic Studio12、NX Imageware13.The software UG8.0 was used to reconstructure the 3d intake manifold with variable length model.

With the rapid economic development of China, Water transport constitutes a potential threat to the aquatic environment, human life and production. In this study, the complex ecological floating bed was studied in oil spill pollution control and ecological environment impact monitoring of inland waters. To explore the complex ecological floating bed in inland, especially the Yangtze River, inland waters. The purpose is to lay the theoretical and technical basis of controlling oil spill efficiently and long-term ecological monitoring. Ecological floating bed with PFU fixed oil-degrading bacteria water oil removal performance tests show that, which is very suitable for oil degradation in water.

Based on the high speed camera combined with a microscopic lens the near-nozzle spray surface structure and flow characteristics of the high pressure diesel fuel jet were investigated. During the steady period of the spray development, the periodically undulatory structure was observed at the circular direction of the jet at the near nozzle area at the injection pressure of 5MPa. The atomization of the spray improved and the periodical structure was veiled by fine droplets at higher injection pressure of 40MPa. During the closing period of the nozzle lift, the spiraling shape was also observed along the surface of the fuel jet which indicates the internal helical flow characteristic.

There is a relationship of unity of opposites between the construction and operation period of the project.When the construction period of the project is shorten and the project is put into production in advance, income of operation period will be increased, at the same time, it will cause the increase of construction cost.Combining time-cost optimization with the financial evaluation of the project, from the perspective of the owner, on the basis of considering the capital time-value and the impact of large equipment replacement on the income of operation period, time-cost dynamic optimization model which maximize the project life-cycle net present value and is proved to be necessary and feasible through the case is established.

The performance of the engine air intake system directly affect the working performance and fuel consumption, where the intake manifold design is the key.In this paper aimed at L91 Engine intake manifold ,firstly theRE(Reverse Engineering)technology was usedto rebuild the3d model of intake manifold.And then the internal flow zoneof the intake manifoldwas meshedin the pre-processing software ICEMand the internal flow fieldwas analyzedin the softwareof Fluent.The numerical model was verified by comparing the simulated and measured results. And then based on the numerical analysis of the internal flow characteristics of the intake manifold, the structure of variable-length intake manifold was come up with and finally was numerically proved to be better than the normal one.

Numerical simulation of the combustion and emissions of HPDI engine under different natural gas substitution rate was performed using AVL FIRE . The effects of natural gas substitution rate on cylinder average pressure, temperature, heat release rate, NO and Soot were analyzed under four typical conditions. Cylinder average pressure and temperature decrease with increasing natural gas substitution rate. Furthermore, the NO emission will decrease significantly under the same circumstances.

In some practical application of target recognition with sensors, the sensors will give the recognition sequence of targets, which is more detailed than the single recognition result. How to properly construct the basic probability assignment by the recognition sequence becomes the key to successful application of evidence theory. For the recognition sequence of the target recognition results of general sensor is incomplete, and the importance of the types in the recognition sequence is in descending order, this paper proposes a method to construct weights of recognition sequence, the basic probability assignments constructed by the weights are closer to the real recognition results. Simulation results show that this method is more reasonable and effective than the method of contrast.

SBN(Series Bayesian Network) model and constructing algorithm of BN are introduced, and advantages and disadvantages of constructing SBN with MEBN(multi-entity Bayesian networks) are pointed out. Aiming at the demands of constructing SBN, expression of Markov MFrag (MEBN Fragment) within MEBN system is clarified, and probability mapping pseudo MFrags are added, then SBN constructing algorithm based on Markov extended MEBN system is studied and the constructing procedures are illuminated by an example.

This paper attempts to employ the matrix of Strengths, Weaknesses, Opportunities, Threats (SWOT) to establish an evaluative index system for software enterprises in Jilin Province. The SWOT analysis is performed in combination with the Analytic Hierarchy Process (AHP) to determine the relative weights of various criteria in the analytic hierarchy as they are related to the overarching goal. The ultimate assessment of the developmental status of those provincial IT enterprises from the local (departmental/segmental) to the global (corporate/industrial) level will then be derived by applying a fuzzy comprehensive evaluation matrix in accordance with the principle of maximum associations. This approach promises to overcome drawbacks commonly found in conventional hierarchical analyses, where frequent adjustments and tests are often required to make results from judgmental matrix consistent. Examples with concrete analytic results have shown that this innovative, synthetic method is of promising guiding significance to corporate strategic formulations.

Through nation-wide and various provinces and regions of the country's gross national product and software industry data Investigation. Combined with industrial concentration index method and location entropy method on the cluster development of software industry and software industry in Jilin province has carried on the empirical research, analysis the software industry in Jilin province while keeping the sustainable development. But the agglomeration development is weak. The software business income, agglomeration degree and the speed of converging in the software industry are below the national average.

This paper studied the changes of wave height and wave driven current in Zhangjiabu sea, which was caused by the installation of wave farm, with Delft3D model. First, the changes of wave height in Zhangjiabu were computed in condition of different absorption rate. Then, the wave induced current near Jinghaijiao cape was calculated, where the change of wave height is largest. Last, 12 points in depth of 3m are used to study the changes of wave induced current velocity. The result show that the wave height and wave driven current will decrease after the wave farm installed.

The complicated cavitating flow inside diesel nozzles has long been concentrated on. Based on the visualization experimental system, cavitating flow characteristic inside transparent nozzles with different length-diameter ratios was investigated in this paper. Experimental results showed that the cavitation is easier to occur for diesel than for biodiesel, and the longer the length of the orifice is, the harder the cavitation and hydraulic flip phenomenon to occur. Discharge coefficient of diesel was higher than that of biodiesel in single-phase flow region, while got much smaller than that of biodiesel in the cavitating flow and hydraulic flip regions.The spray cone angle of diesel was larger than biodiesel in cavitating flow regime, and got much smaller with the increasing of the length-diameter ratios under the same level of injection pressure in diesel and biodiesel fuels.

As cavitation inside diesel nozzles can improve the spray characteristics, it has long been a hot issue. And together with the increasing attention of biodiesel, it is essential to identify the difference of cavitating flow characteristics between diesel and biodiesel. What’s more, the hydraulic flip phenomenon and cavitating flow with decreasing injection pressure hasn’t been studied. Based on this, cavitating flow inside transparent nozzles of diesel and biodiesel fuels with increasing and decreasing injection pressure was investigated in this paper. Experimental results showed that are quite different from the disappearance of it and it is harder to disappear. Biodiesel and longer nozzle orifices were hard for the hydraulic flip phenomenon to occur, and the disappearance of hydraulic flip phenomenon has great influence on the spray cone angle and the discharge coefficient.

The oil spill dispersant called “elimination agent of oil” is used to disperse the oil slicks to facilitate the natural elimination of oil. Oil spill dispersants are used to enhance the rate of natural dispersion of an oil spill at sea. There is growing acceptance worldwide that use of dispersants to counter the effects of an oil spill offers many advantages and can often result in a net environmental benefit when considered in relation to other response options. Timely spraying oil spill dispersants is the main measures to remove surface oil pollution and to prevent fires, when mechanical recycling cannot be used in case of emergency. Efficient and environmentally friendly oil spill dispersant meet both the emulsification dispersion and zero pollution to the environment, and has been more widely used and developed.

By using AVL FIRE code, three-dimensional numerical simulations of the diesel-natural gas injection characteristics in a direct injection diesel-natural gas engine were conducted. The effects of the start of injection (SOI) of the pilot diesel and natural gas injection velocity on combustion and emission performance were investigated. The results showed that diesel-natural gas injection characteristics have an important influence on the subsequent combustion and emission. NO and Soot emission performance is better when the SOI was 36°BTDC (Before Top Dead Center), and a larger natural gas injection velocity usually leads to a lower engine economical efficiency.

The impinging streams mixer is a new type micromixer. The cavitation phenomenon occurring in the mixers with T-shaped impinging streams (TS), conical impinging streams (CIS), vortex streams(VS) were investigated, respectively. The distribution of flow field in the mixer was simulated and calculated by commercial software Fluent 6.2.1. The results showed that under the same working conditions, a more obvious hydrodynamic cavitation may occur in the CIS type impinging stream than that in the CIS type or the VS type, and the vortex flow lead to an extension of the material residence time in the mixer. The distribution of turbulent kinetic energy and gas holdup were obtained by numerical simulating hydrodynamic cavitation under different entrance pressure conditions. It is showed that when the outlet pressure keeps a constant value, hydrodynamic cavitation can be enhanced by increasing the entrance pressure. The above research can be contributed to the producing of biodiesel and the solving of the key technical problem of oil and alcohol heterogeneous mixing.

From a theoretical perspective, this paper develops a systematic approach to analyze the transient characteristics of the low voltage ride through in three-phase short-circuit rotor current. Firstly, the steady state current mathematical model of the system is described. And then, the short-circuit rotor current dynamic characteristic during the low voltage fault is analyzed, the resistance value and switching strategy of crowbar are discussed. Finally, the simulation results and the theoretical analysis manifest that appropriate crowbar reactance value and switching time can improve LVRT control characteristic and grid stability.

Airfoil has great influence on the performance of axial fan. In order to study performance of axial fan. Four kinds of airfoils have been applied to optimize the impeller of axial fan. The 3D internal flows of the axial fan under different operating conditions were simulated based on a steady numerical method in ANSYS CFX 14.5. The results show that the curve of total pressure of the fan with LS airfoil blades is slightly steeper, and that of the fan with CLARK-Y(C=11.7%) (C is the blade thickness ratio) airfoil blades is relatively flat. The total pressure of the axial fan with CLARK-Y(C=11.7%) blades is highest among others. While achieving the highest efficiency in all the operating conditions except the lowest flow rate. Moreover, the blades loading of the CLARK-Y(C=11.7%) airfoil blades fan is entirely more uniform than that in others. The turbulent kinetic energy distribution on the leading edge of blades shows that the axial fan with CLARK-Y(C=11.7%) airfoil blades fan can improve the turbulent kinetic energy effectively.

In this work, potassium tantalate (KTaO3) particles were synthesized using a low-temperature hydrothermal method. The phase structure of samples prepared was performed by X-ray diffraction (XRD). The result revealed that it belongs to cubic crystal. The electrochemical behaviour of a KTaO3film coated electrode was investigated in 0.1 mol dm-3KCl containing 5 mmol dm-3K3Fe (CN)6with cyclic voltgrammetry (CV). The CV results indicated that the KTaO3film coated electrode exhibited excellent electrochemical stability. The electrochemical reaction of K3Fe (CN)6on the KTaO3film coated electrode was a diffusion-controlling process.

A study was carried out on the influence of different back pressures on internal flow of diesel injector nozzles. For this study, a flow visualization experimental system equipped with a pressurized chamber was setup. Experimental results show that, with the injection pressure remain constant and increase back pressure leading to the cavitation area diminished gradually and even disappeared. With a same pressure difference, higher back pressure test condition promoted the outlet mean velocity and inhibited the occurrence of cavitation inception, which demanded a larger pressure difference to make it happen. Moreover, it also resulted in a relatively large flow losses to the single phase flow compared to the cavitating flow.

Three kinds of carbonaceous materials with different structural and chemical properties, Carbon Black (CB), Multi-walled Carbon Nanotubes (MWNTs), and Graphene Oxide (GO), were well suspended in sodium alginate (SA) solutions, and the suspension rheological behaviors were investigated in details. Steady rheological results showed that the suspensions exhibited same shear-thinning behaviors as SA solution. Dynamic rheological results showed that the complex viscosity (η*) was similar to that of steady rheological measurement, and both SA solution and SA/carbonaceous materials suspensions exhibited liquid-like behaviors, confirmed by the loss modulus larger than the storage modulus. The loss factor tanδremarkably decreased for SA/GO solution compared with SA/CB and SA/MWNTs suspension at the same concentration, indicating the increase of elasticity via interactions between the GO and SA.

Using configuration software MCGS7.2 to achieve biochar production device monitoring, real-time data display, historical data query and store data dump. The interface of human machine interface is used to choose the monitoring function, it makes the operation of the monitoring system be more centralized. There are many features, such as stable performance, low cost and simple operation in system, which can bring great convenience to biochar production device monitoring.

We have investigated the effect of zirconium oxide on the thermal degradation and flame retardancy of viscose fibers. ZrO2/cellulose fiber was prepared by wet spinning. Combustion behaviour and flammability were assessed using the limiting oxygen index (LOI) and thermogravimetric analysis from ambient temperature to 800°C and cone calorimetry. LOI results showed that the ZrO2 increased the LOI of viscose fiber from 20% to 26%, which showed that ZrO2 particles had a positive effect on cellulose flame-retardancy. Results from thermogravimetric analysis (TG) indicated that the ZrO2/cellulose fibers produced greater quantities of residues than viscose fibers. The combustion residues were examined using the scanning electron microscopy, indicating that ZrO2/cellulose fiber produced consistent, thick residues. Cone calorimetry indicated that heat release rate and total heat release values of ZrO2/cellulose fiber were less than those of viscose fibers.

Cellulose-insoluble silicate (talcum powder) hybrid fibers with 10%, 20%, 30% silica contents were prepared by wet spinning. The flammabilities and combustion processes were evaluated by the limiting oxygen index (LOI) and cone calorimetry. The LOI results suggested that the hybrid fibers were flame retandant with the LOI value of 22, 25 and 27, as compared to 20 of pure cellulose fibers. Cone calorimetry showed that the rate of heat release value and total heat release value of hybrid fibers decreased. Hybrid fibers with 20% SiO2 loading is the best flame retardant sample. SEM studies of residues after cone calorimetry indicated that the hybrid fibers produced tight and hard residue crusts.

As a study of natural gas engine, three-dimensional numerical simulations of diesel injection rates were conducted by using AVL FIRE code. And particularly the effects of the injection rates in the pilot diesel jets on the engine combustion and emission were analyzed. It is found that injection rate in the pilot diesel jets plays an important role on the emission, and slow ending rate of the injection keeps lower NO and Soot.

A good manufacturing workshop layout can influence the profit of the manufacturing enterprises after the product coming on stream. Facility layout of workshop is a combinational optimization problem. The multi-objective optimization model which integrates the available problem of facility layout of workshop is established. Adaptive Genetic Algorithm is presented because of the disadvantage of simple Genetic Algorithm in solving this model. This algorithm use the adaptive crossover and mutation strategy which is used to nonlinear processing for crossover rate and mutation rate, then crossover rate and mutation rate are changed with the colony adaptation degree of each generation. It has some advantage, such as higher search speed, higher convergence precision, and so on. Finally an example is used to show the effectiveness of the method.

A Novel adsorption apparatus for processing hazardous chemicals diffusion and volatilization of inland waterway transportation is developed. The adsorption apparatus is lightweight and has high effective absorption capability for processing the gas chemicals produced by inland river transportation. Meanwhile, the experiment for analysis and processing for the bulk chemicals gas is carried out. The results showed that the concentration of chemicals gas decreased by 69-83% comparing with that not using the device.

This paper studies on jointed pricing decision of Brick-and-Click Retailers under uncertain demand, based on the two-item newsvendor model. Firstly, the two-item newsvendor model is built based on profit maximization. Then, the concavity of objective function is proved and the solving method is given. Moreover, the solutions of the model and the influence of demand transfer coefficient to pricing, productivity and profit are analyzed numerically. The results show that the traditional retail channels pricing and productivity will decrease while e-commerce channels pricing and productivity and retailer profits will grow with the increase of demand transfer coefficient.

The availability of atmosphere laser communication systems in dependence on weather conditions and on atmosphere laser link parameters, such as transmitted optical power, beam divergence, or link path distance, is discussed. A number of phenomena in the atmosphere, such as fog, can affect beam attenuation. In this work, the analysis and simulation of the empirical models (like Kruse, Vasseur, etc) indicate that the predicted attenuation of those models is similar and the main attenuation factor of 532nm laser propagation in atmosphere is aerosol particle. Attenuation caused by fog, which can be expressed as a function of the link distance, wavelength, and meteorological visibility, is calculated from visibility data collected at several locations in Guilin. Statistical evaluation of the attenuation caused by fog and the power link margin calculated from atmosphere laser communication link parameters are used for calculating the link availability.

Gamma-Gamma distribution model is widely used in studying the impact of the atmospheric turbulence on the Free Space Optical communication systems. This study introduces the Gamma-Gamma distribution model, simulates and studies the spot changes over distance, wavelength, turbulence structure constant and transmit aperture, respectively. Finally, the simulation results show that the Gamma-Gamma distribution is more suitable for middle-strong turbulence than weak turbulence.

Austenization is an important stage during the quenching-tempering heat-treatment process of X65 microalloyed pipeline steel, because it can influence the development of final microstructure and mechanical properties. In this paper, a detailed investigation was carried out on the austenizing transformation process in X65 microalloyed pipeline steel using high-resolution dilatometric technique and microstructure observations. According to the obtained dilatometric curve during continuous heating, the austenizing transformation process in X65 steel was apparently composed of two stages, 740-765°C and 765-875°C respectively. In order to clarify the microstructure evolution during the two stages, interrupt heat treatment tests were performed and subsequent microstructural observations showed that the first stage (740-765°C) was corresponding to the dissolution of fine carbides particles and the second stage (765-875°C) was corresponding to αγ phase transformation. Firstly, austenite nucleates at interfaces between fine carbide particles and ferrite matrix due to the high interface energy there and then the carbide particles dissolve into the austenite nucleus, which constitutes the first stage. After the fine carbide particles dissolve completely into the austenite nucleus, the ferrite matrix relatively far from the original carbide particles needs higher thermal driving force to transform to austenite, therefore the major αγ transformation occurs at higher temperature range (the second stage).

The visualization experimental setup of micro free-piston engine has been built, the process of single shot compression combustion in micro combustion chamber has been observed by the high-speed digital camera; Based on the propane combustion kinetics, the numerical calculation method for combustion process coupling with the free-piston movement was put forward, through editing the dynamic mesh subroutine in STAR-CD, the process of homogeneous charge compression ignition (HCCI) in the micro chamber was studied; The influence of piston initial state on HCCI combustion process was analyzed , indicating that the piston mass directly affects the homogeneous gas compression ratio, ignition time, single combustion process cycle and the changes of combustion pressure and temperature, all this research can be the basic theories for designing the micro free piston engine .

Stable fluorescent carbon nanoparticles (FCNPs) with excellent water-solubility were prepared firstly by one-step ultrasonic treatment from the blending of glucose and sodium hydroxide. Then, the fluorescence calcium alginate fibers were successfully prepared through wet spinning, using the mixture of FCNPs and sodium alginate solution as the spinning dope. The fluorescent property of FCNPs and fibers were investigated using fluorescence spectrophotometer. Single fiber strength tester was used to measure the strength of the fluorescence fibers. The results showed that both FCNPs and fibers emitted bright blue color under 350nm wavelength UV irradiation. The strength of the fibers was improved when the content of FCNPs in the fibers achieved certain value.

A novel nanocomposite (MB/CRG) was fabricated by a simple and fast method. The method is as follows: graphene oxide (GO) was dispersed in methylene blue (MB), and then the MB/GO was chemically reduced to MB/chemically reduced graphene (MB/CRG) by hydrazine hydrate. MB can greatly improves the dispersity of CRG in water and at the same time, the electrochemical activity of MB/CRG nanocomposite increased. The MB/CRG nanocomposite was used to modify the glass carbon electrode (GCE), and the MB/CRG/GCE was obtained. We investigated the electrochemical behavior of uric acid, NaNO2, Quercetin and p-nitrophenol at MB/CRG/GCE and found that the modified electrode had the best catalysis towards these molecules compared with MB/GCE and CRG/GCE. The MB/CRG/GCE showed good reproducibility and stability.

A simple and efficient molecularly imprinted sensor (MIPs/GR/GCE) was firstly prepared by electropolymerization of pyrrole in the presence of bovine serum albumin (BSA) in an aqueous solution based on a graphene modified glassy carbon electrode for the selective recognition of bovine serum albumin. The prepared sensor was characterized by differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS), in which [Fe(CN)6]3−/4−was used as an electrochemical active probe. The results showed a wide linear range from 1.0 × 10-3to 1.0 × 10-9g/mL. And the imprinted biosensor indicated excellent selectivity and high sensitivity.

Reduced graphene oxide (RGO) supported platinum electrocatalyst was successfully synthesized on the glass carbon electrode by the electrodeposition method. Cyclic voltammetry (CV) and amperometry were used to evaluate the catalytic activity of the Pt/RGO modified electrode towards methanol oxidation. The results revealed that the as-prepared catalyst exhibited high electrocatalytic ability in methanol oxidation, which could be attributed to the excellent properties of the reduced graphene oxide as supporting materials.

A new experimental apparatus has been developed for measuring the thermal conductivity of liquid by the two transient hot-wire method, which is based on the theory of one-dimensional unsteady heat conduction in infinite medium. The glass tubes, the heating line source and temperature measurement devices are designed in this experiment. As the temperature controller, low-temperature bath provides a constant water bath environment and current calibrator is the power source. Wheatstone bridge is used to test the relation between the temperature changes and resistance. Data acquisition and control unit is data acquisition devices of the Wheatstone bridge. As the temperature coefficient of platinum wire resistance is calibrated. It can be used to measure 32 groups of data from 10°C to 40°C at the every 10°C according to the experimental steps.

Diesel spray characteristic s is affected by nozzle geometry and then influences the subsequent combustion and emission, so it's important to get the detail nozzle geometry dimensions. In this paper, the X-Ray phase contrast imaging technique was proposed to measure the nozzle geometry. With X-microtomography technique and three-dimension reconstruction technique, the internal structure of nozzle is constructed. The non-destructive measurement was performed and the detail structure of nozzle was got.

The engine cooling water jacket has a major impact on the efficiency of the engine. In this paper the flow in the cooling water jacket of the six-cylinder four stroke water-cooled diesel engine was studied with the commercial software of STAR CCM+. Results of the simulation reveals that velocity has little effect on the flow field distributions. Dead zone in engine cylinder head appeared far away from the inlet of the flow. But it could be avoided or improved effectively by arranging the inlet and outlet at opposite side of the cooling water jacket. Further study suggests that a good flow field distribution can be achieved near the entrance if one inlet was put at the same side of the outlet and the other the opposite side, while the wall was impacted fierce due to the strong turbulence and eddy existed. Finally some advices were given to solve the problem.

Three novel kinds of support film, including PVDF-PAA film, PVDF·TiO2–PAA film and PVDF–g–AA film, were synthesized and used to immobilize the Pd/Fe bimetallic nanoparticles (NPs). The immobilized Pd/Fe bimetallic NPs systems were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, contact angle analysis, and X-ray photoelectron spectroscopy. The dechlorination efficiency of the immobilized bimetallic NPs systems were tested and discussed by dechlorinating monochloroacetic acid (MCAA). Comparing with free suspended Pd/Fe NPs, bimetallic NPs with support films appeared better catalytic dechlorination efficiency, and the dechlorination efficiencies of 10 mg/L MCAA in 120 min by Pd/Fe NPs immobilized in PVDF–PAA film, PVDF·TiO2–PAA film and PVDF–g–AA film were 56.33%, 71.01% and 75.51%, respectively.

A novel composite was firstly synthesized by compositing graphenes (G) and carbon nanotubes (CNTs) and then a new composite modified electrode (G/CNTs/GCE) was prepared by coating the resulting composite on the surface of the glassy carbon electrode (GCE). The composite modified electrode G/CNTs/GCE showed great electrochemical activities which were studied by sensitive determining the electrochemistry behaviors of uric acid (UA). It revealed when the concentration range of UA changed from 1×10-7 mol/L to 1×10-3 mol/L, the peak currents had linear relationship with the concentration of UA in the phosphate buffer solution (PBS) which the value of pH is 7.0. And the linear equation is ip (μA) = 21.55C+28.94 (C: mmol/L), with the related coefficient 0.9964.

Experimental research on calcium alginate fibers thermal degradation and flame retardancy under catalysis of metallic salts was done by limiting oxygen index (LOI), scanning electron microscopy (SEM), and thermogravimetric analysis (TG) methods. LOI results show that with increasing calcium ions content, the flame retardant properties of the calcium alginate fibers improves further. The residues of calcium alginate fibers gradually retained fiber shape and on the surface of the residues the holes reduced, with the calcium ion content increasing. TG indicates temperature at maximum rate of weight loss (T-max) was clearly shifted from 246 °C for alginic acid fibers to 244°C, 236°C, 208°C, 205 °C and 203°C (SCa-1-1# calcium alginate fibers, SCa-2-2# calcium alginate fibers, SCa-3-3# calcium alginate fibers, SCa-4-4# calcium alginate fibers, SCa-5-5# calcium alginate fibers), respectively. The thermal degradation residues at 1000°C for different calcium alginate fibers are 13.7%, 16.1%, 17.2%, 18.2%, 18.4%, 19.2%, separately. Further discussion of the combustion process and flame retardant mechanism is presented.

Flame retardance and thermal degradation of CMC-Na fibers were investigated using limiting oxygen index (LOI), thermal gravimetry (TG), differential TG (DTG) and Scanning electron microscopy (SEM). The LOI values of different CMC-Na fibers are 23, 26, 28.5, 31 and 34, compared with about 20 for viscose fiber. TG and DTG studies indicate that the temperature of maximum degradation rate and the maximum degradation rate for CMC-Na fibers are much lower than those of viscose fiber. However, CMC-Na fibers generate much more residues or carbonaceous char than does viscose fiber. The increase of sodium ion content, the carbon residual also increases. SEM studies of combustion residues after LOI testing indicate that all CMC-Na fibers produce intumescent, hard and brittle residue crusts.

Temperature-sensitive calcium alginate-based microspheres were prepared in two steps. Firstly, free-radical polymerization of temperature-sensitive N-vinylcaprolactam monomer was performed in aqueous solution of sodium alginate, yielding a mixed aqueous solution bearing temperature-sensitivity composed of poly(N-vinylcaprolactam), sodium alginate-graft- poly(N-vinylcaprolactam) and sodium alginate. Then temperature-sensitive composite microspheres were prepared by inverse emulsification-crosslinking using the as-prepared solution as water phase, n-hexane as oil phase, Span-85 and Tween-85 as emulsifiers and calcium chloride as crosslinker respectively. The morphology and temperature-sensitivity of the composite microspheres were investigated by scanning electron microscope and turbidity method respectively. The controlled release behavior of the microspheres towards temperature was investigated preliminarily using berberine as a model drug.

A novel Nafion/PMB/G/GCE was prepared by firstly electro-polymerization of MB to G/GCE and then coating Nafion on PMB/G/GCE. The as-prepared modified electrode combining the advantages of Nafion, methylene blue and G was employed for the sensitive detection of rutin. The results showed that the peak current of rutin obtained on Nafion/PMB/G/GCE was obviously high compared to bare electrode and G/GCE. Under the optimized value of pH, which was pH 3.0, peak current of rutin had good linear relation with the scan rate. At the same time, peak current increased linearly with increasing concentration of rutin. The linear range was from 5×10-7 mol/L to 1.2×10-5 mol/L, and the detection limit was 9.5×10-8 mol/L

Glassy carbon electrode (GCE) was modified using graphene (G), quercetin (Qu) and Nafion in this sequence to fabricate Nafion-Qu-G composite-modified GCE (Nafion/Qu/G/GCE). The as-prepared modified electrode combining the advantages of Nafion, Qu and G was employed for the selective and sensitive detection of dopamine (DA) in the presence of ascorbic acid (AA) and uric acid (UA). Compared with GCE, Qu/GCE, G/GCE and Qu/G/GCE, the Nafion/Qu/G/GCE was more electroactive and selective for DA. Differential pulse voltammetry (DPV) was used for electrochemical detection, the separations of the oxidation peak potentials for AA-DA and DA-UA were about 304 mV and 136 mV, which allowed selectively determining DA. In phosphate buffer solution (PBS) of pH 6.8, the Nafion/Qu/G/GCE provided a detection limit of 2.31×10-8 mol/L (S/N=3) for DA. Linearity (R=0.9963) of the peak currents against the concentration of DA was found over the range of 1.0×10-7 to 1.0×10-3 mol/L. Furthermore, the modified electrode exhibited good reproducibility and stability.

A zwitterionic copolymer has been synthesized and a common optimum concentration of dispersant for the stabilized Al2O3suspensions is found at 0.04wt%, which represents the adsorption saturation limit of polyelectrolytes at Al2O3–water interface at pH = 10. Based on the results from rheological measurements, involving the effect of dispersant concentration, a stable broader dispersant concentration range of 0.4wt% ~ 0.22wt% is observed for suspensions with solids loading ≤ 50vol%, a stable broader pH range of 7.0 ~ 11.2 for suspension with solids loading ≤ 50vol%, and a stable pH range of 1.2 ~ 2.0 for suspensions with solids loading ≤ 40vol%.

The effects of an anionic polyelectrolyte on the dispersion of 3Y-TZP suspensions in aqueous medium have been systematically investigated. The results of rheological experiments show that at CD = 0.5 wt% (CD : dispersant concentration), the dispersant could afford well-dispersed 3Y-TZP suspensions over a wider range of solids loading, owing to the stronger electrostatic repulsion between particles resulting from the monolayer coverage of the particle. But as CD ≤ 0.5 wt% or CD ≥0.5 wt%, the stable 3Y-TZP suspensions can only be achieved at a relatively lower solids loading, which are ascribed to the reduced repulsion barrier between particles owing to the lower ζ values of particles and the higher ionic strength in the system, respectively.

Zirconia-graphene composite (ZrO2-G) has been successfully synthesized via decomposition of ZrOCl2•6H2O in a water-isopropanol system with dispersed graphene oxide (GO) utilizing Na2S as a precursor could enable the occurrence of the deposition of Zr4+ and the deoxygenation of GO at the same time. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were used to characterize the samples. It was found that graphene were fully coated with ZrO2, and the ZrO2 existing in tetragonal phase, which resulted in the formation of two-dimensional composite.