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Surface-enhanced Raman spectroscopy (SERS), having the advantages of high detection sensibility and fast analysis speed, meets the requirements of the detection of sulfur content in simulated gasoline. The optimal preparation conditions of nano-silver substrate which played an important role in enhancing Raman signals was mainly studyed in this paper. Potentiostatic oxidation-reduction method was selected to prepare roughened silver electrode as the nano-substrate. The influences of electrolyte, potential and reduction time were investigated. It shows that bromide ion in electrolytes and nearly balance potential could lead to much better result that relative area intensification factor is equal to 81746.

Phenolic resin modified with methylvinylcyclosilazanes (MVSZ) were prepared and their flame-retardant properties were investigated, and results exhibited that the Limited Oxygen Index (LOI) values increased with the content increasing of MVSZ, and the LOI reach to 40.8, when the content of MVSZ was 26.0%. The flame-retardant and mechanical properties of polyester fabrics reinforced phenolic resin modified with silazanes (PFMS) composites were measured, the results indicated that the LOI and flexural strength were enhanced compared with those of phenolic resins composites.

In recent years, the development of digital libraries also encountered a lot of problems, the cloud computing was applied to digital libraries can solve the problem of information on demand and optimal scheduling of resources and transaction processing capabilities effectively, So as to achieve the purpose of improving the efficiency of resource of digital library and information security. From the digital library of cloud computing and personalized information services status in this paper, the study and found a problem about the digital library information services at this stage, let the virtualization cloud computing, the key technology of distributed data storage, massive data processing and cloud platforms used in building digital library of personalized information service with cloud platform, and deployment cloud services on the platform.

To study the effect of Angelica keiskei chalcone (AC) on microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression on mice hepatocarcinoma cells. Fifty mice were inoculated with hepatocarcinoma H22 cells and divided into 5 groups. Group one to three were administered orally with AC by 5, 25 and 50 mg/kg/d, respectively. Group four was given Endostar 4mg/kg/d by intraperitoneal injection and tumor control group (group five) was given with normal saline. All mice were sacrificed after 10 days. The proliferation activity of hepatocarcinoma cells was determined by methy tetrazolium (MTT) assay, and the levels of the MVD and VEGF protein expression were detected by immunohistochemistry method. The AC inhibitory rates for tumor size were 4.20%, 30.47% and 39.42% at AC treatment dose of 5, 25, and 50 mg/kg, respectively. The average MVD count was 14.2, 11.2 and 8.5 at treatment dose of 5 mg/kg, 25 mg/kg and 50 mg/kg AC, respectively. The protein levels of VEGF in mice treated with 25 mg/kg and 50 mg/kg AC were significantly decreased. The results showed that AC could inhibit tumor angiogenesis effectively and the inhibition mechanism might be associated with the down-regulation of VEGF.

Through researching the fault vibration signal characteristics of planetary gearbox, various forms of quadratic phase coupling phenomenon were found in the signals. Bispectrum has properties such as detecting the quadratic coupling phenomena and restraining gaussian noise signal, and it can be well used in the planetary gearbox fault diagnosis. Meanwhile, the sun gear distributed fault (gear wear) and partial fault (root crack, partial broken teeth) are simulated in the wind turbine test bench built in the laboratory. By analyzing the structure characteristics of its frequency through bispectrum, the fault of the gear is effectively diagnosed.

This paper examined the effect of the urbanization on CO2 emissions in China, using the semi-parametric panel data model. The results show that an inverted U-shaped relationship exists between urbanization and CO2 emissions in China and further development of urbanization is beneficial in reducing CO2 emissions.

The soft soil in Pearl River Delta regions is characterized with high water content, high compressibility and low bearing capacity. Therefore, when building the structures on such foundation, it’s necessary to pay attention to the deformation and stability. The projects' practice shows that, when analyzing the stability on foundation pit or slope with soft interlayer, it should not only calculate the overall stability of the slope, but also calculate the stability or bearing capacity of the foundation. Although sometimes the stability of the slope meets the requirements, it doesn’t means that the bearing capacity of the foundation meets the requirements because of the existence soft interlayer, the limitations of the circle slice method and the difference between the sliding surface and the actual sliding surface.

Anorthite good sintering properties and strength, there promotion prospects in oil and gas fields in the ceramic proppant fracturing. In this experiment, fly ash, coal and limestone as raw materials by high-temperature reaction sintering ceramics, Explore mineral composition, the sintering temperature of the final preparation phase of the resulting composition and physical properties of the impact, better product performance obtained at 1250 °C.

Most high-speed rail stations are generally built in the periphery of the city. Therefore, it is necessary for the government to build new transit routes to meet the traffic demand in the emerging city unit around the high-speed rail stations. This paper formulates a model based on genetic algorithms (GA) to design transit route considering various evaluation standards. Numerical example is set up to illustrate the model and algorithm.

In this paper, the hygroscopic properties of three different gauze, that is common medical gauze, absorbable carboxymethyl gauze and absorbable oxidized gauze, were compared, and the kinetic analysis were studied. The results showed that, at 298K and RH80%, the moisture absorption rate of the three kinds of gauze follows the order of absorbable carboxymethyl gauze > absorbable oxidized gauze > common medical gauze. The moisture absorption kinetic analysis of the three kinds of gauze indicated that the second-order model proposed fits experimental data well with the correlation coefficient greater than 0.999.

According to the resonance mechanism, power system forced low frequency oscillations can be aroused by power disturbance of prime mover. Therefore, the causes of turbine power disturbance were analyzed. The coupling model between turbine-governing system and power system was established in MATLAB. The possibility of governing system disturbance inducing the variation of control valve position and turbine power was researched in detail. The simulation results indicate that high level variation of control valve can be induced by the rotor speed deviation disturbance, if the speed-droop ratio of turbine-governing system is too small in local running position; power system low frequency oscillations of resonance mechanism might be caused by the disturbance of rotor speed deviation, when it’s frequency is close to power system natural oscillations frequency. Oil-pressure pulsation is easily happened in hydraulic governing system. If the frequency of oil-pressure pulsation is near to power system natural oscillations frequency, power system low frequency oscillations of resonance mechanism can be induced.

The mechanism of power system low frequency oscillation was discussed in this paper. The coupling model between turbine governor system of plant and power system was established in MATLAB. The possibility of power system low frequency oscillation induced by unit-grid coupling was researched in detail. The simulation results indicate that power system low frequency oscillation will occur under disturbance, if a high derivative gain is used in PID controllers of hydraulic turbine governing system and partial derivative of turbine power output with respect to head varies with load. As for steam turbine, the PID parameters of governor system have important effect on small-signal stability of power system when the damp of power system is not very strong. The power oscillations caused by disturbance is decreased with the use of PID controller in governing system, whereas power oscillation is increased with the use of PI controller.

Fabrication of superhydrophobic structure by femtosecond laser become more and more popular in recent years, because it’s inexpensive and micro/nanostructure can be controlled compared with other methods. This paper proposes an approach to fabricate large scale superhydrophobic structure directly on nickel (Ni) surface by femtosecond laser and the apparent contact angle (CA) on the Ni surface can reach 134° without further coating any low surface energy materials. With low laser power, typical laser-induced periodic surface structures (LIPSS) at the submicron level can be observed. With high laser power, periodic ripples with microstructure covered by LIPSS can be observed. The micro/nanostructure on Ni surface is directly replicated onto PDMS and after replication the CA on PDMS surface can be improved to 153° obviously from CA of 120° on PDMS surface without micro/nanostructure. The higher laser power can results in the larger CA. This replication method can be applied for fabricating large scale superhydrophobic structure and the replication master can be used many times.

In this paper, the exothermal efficiency and exothermal rate were employed to evaluate and optimize the composition of the self-heating material, and the effects of each component were discussed. The final optimized composition as below: reduced iron powder (20%), potassium permanganate (60%), sodium chloride (10%), activated carbon (10%). Under the optimized conditions, the temperature of this self-heating material could up to 100 °C within 2 min and maintain for 20 min, which should be suitable for flameless fast food self-heating or providing heat source for physiotherapy equipment in the medical field.

Methanol-water as solvent, transition metal Y-type zeolite as catalyst, L-lysine was synthesized laminin. Explores the methylation process factors, and the structure of the compound by IR, NMR and elemental analysis were characterized.

To study the mechanism of metal magnetic memory (MMM) testing technology, the stress-magnetization effect on 20 steel specimens with different notch angles under exercise of the geomagnetic field and tensile load is simulated by using the finite element analysis (FEA) software ANSYS. With the stimulation, the stress and magnetic flux leakage distribution of the specimens is given. The results showed that internal stress distribution of different notch specimens under external tensile effects is different; The curves of relationship between damage degree of stress concentration and the distribution of magnetic flux leakage is also related to the defect shape and structure; Magnetization decreases with increases of stress at first and then increases with continuing increase of stress, which is called stress magnetization reversal. It provides an important reference for the quantitative research of metal magnetic memory technology.

To study the correlation effect of multiple defects of metal magnetic memory (MMM) testing technology, the stress-magnetization effect on 20# steel specimen with dual defects under exercise of the geomagnetic field and tensile load is simulated by using the finite element analysis (FEA) software ANSYS. With the stimulation, the magnetic flux leakage (MFL) distribution with different measured paths and different lift-off values of the surface specimen is given. The results showed that the correlation effect of dual defects produce more severe stress concentration phenomenon on the associated region of ferromagnetic specimen, and had no obvious effect on the edge of ferromagnetic materials; Gradient value K of the normal component H(z) of leakage magnetic field in the specimen, as a parameter evaluation of stress concentration in the specimen, has high reliability in areas without correlation effect, but it has no credibility in areas under dual defect correlation effect. Moreover, this article also discusses the influence of measured path and the lift-off value on magnetic memory signals.

Current-voltage (I-V) and impedance spectroscopy are employed to investigate the polarity of TiO2varistor. It is found that TiO2varistor shows typical polarity behavior, i.e., theI-Vcurve is asymmetric, the impedance slightly increases, and the capacitance slightly decreases when the bias voltage reverses. The effects of measuring frequency on impedance spectroscopy are systematically investigated. The results indicate that TiO2varistor behaves considerable polarity under low sweeping frequency. High sweeping frequency (over 103Hz) counteracts the polarity behavior. A model ofmicro-polarized zoneis tentatively proposed to clarify the polarity behavior of TiO2varistor.

This paper aims to investigate the mass and characteristics of colloid in leaching process to provide useful information for assessing the effects of colloid on leach at vertical and safety assessment of the disposal of (ultra-) low uraniferous radioactive waste. The variation of pH, colloid mass and effects on leach were studied at ambient conditions. The experimental results showed that the formation of colloid was strongly influenced by the pH value, it increased with time from 24 h to 96 h, and mass of colloid showed the opposite trend. The mass of colloid increased by the thick of uranium residual ores from 0.2 m to 0.8 m, but the pH showed opposite trend. The colloid morphology was identified using S-4800 scanning electron microscopy (SEM/EDS), and confirmed Al, Fe, Mg, Cs, U, Pr, O, and C as main composition. It implies that the existence of colloids would retard uranium leaching process. The residue grade of different thick nicely verified this point.

This paper mainly realizes scramble in TD-LTE system. It includes the introduction of scrambling; projects form; the process of FPGA implementation and the results analysis. Then it finishes simulation, synthesis and verification of board on Virtex-6.The implementation of results shows that this algorithm of modulation and scramble has a high effectively and good reliability to TD-LTE RF conformance testing instrument.

In order to verify the protocol conformance of RRM (radio resource management) handover procedure in TD-LTE system, We proposed an implementation program of terminal RRM conformance test system with TTCN-3 (Testing and Test Control Notation version 3), designed the testing process of handover in cells, developed the corresponding test cases, and completed the protocol conformance test of Terminal RRM Handover procedure.

In this paper, a mechanical model has been established for elastic support element of high speed winding machine, and an analytical-experimental study has been carried out for the evaluation of frequency dependence the stiffness and damping of the "O" type rubber ring, the key factors which influence the stiffness and damping have been obtained. This lays a foundation for further study on frequency characteristic of kinetic parameters of high speed winding machine elastic support system.

For the problems such as layering and splitting of traditional sandwich structure composite, a resin matrix composite with lattice and interface reinforced structure has been designed, The composite material has high specific strength and stiffness. On this basis, a road pavement developed by this composite material used in engineer urgent was designed. The connection between the pavements was designed for quick assembling, which could make the pavement assemble operation was simple, fast and reliable. Experiments and engineer application indicate that the composite pavement has characters of low cost, simple maintenance, corrosion resistant and reusable, which has a great application prospect.

For the problems such as layering and splitting of traditional sandwich structure composite, a resin matrix composite with lattice and interface reinforced structure has been designed, and using vacuum forming process was developed in this paper. The composite material has high specific strength and stiffness. On this basis, a road pavement developed by this composite material used in engineer urgent was designed. This composite pavement with characters of light weight, high strength and good toughness, and its surface plate was hard, wear-resistant and non-slip. The connection between the pavements was designed for quick assembling, which could make the pavement assemble operation was simple, fast and reliable.

Through the scanning electron microscope and energy spectrum analysis of vanadium slag after calcination at different temperatures of Panzhihua Iron and steel in industrial production, analyzed the change of morphology and composition of the various main phase, Focuses on the change process of two main vanadium containing phase which are vanadium spinels and calcium vanadate. The vanadium spinels into calcium vanadate optimal temperature range is 800 ~ 900 °C, and provides a theoretical basis for the extraction process of vanadium, which can further improve the industrial production of vanadium.

Tibetan Antelope, Tibetan wild donkey and wild yak are protected endangered wild animals in China, the endangered ungulates in the Qinghai-Tibetan Plateau. As the national first class protected wild animals in China, their survival and sustainability received extensive concern. We evaluate the habitat suitability in the alpine desert ecosystem. The percentages of high suitability habitat for Tibetan Antelope, Tibetan wild donkey and wild yak are 18.03%, 20.06% and 18.14%, respectively, mainly in the south and east of the alpine desert ecosystem. The habitat of Tibetan Antelope and Tibetan wild donkey are more similar for a certain overlap of their habit. The habitat of wild yak is more concentrated in the eastern. Major of the high suitability habitat are protected in the national nature reserves (NNRs), while there is still approximate 30% adjacent to the boundary of the reserves. The Qiangtang NNR's protection proportion is higher than others, and the conservation efficiency in the Kekexili NNR is highest, indicating the importance of Qiangtang NNR and the rational allocation of protection resource. The lower conservation efficiency in Arjin Mountain NNR may be due to the poorer geographical natural conditions.

Hengshui Lake National Nature Reserve is one of the most ecologically valuable freshwater wetlands in the northern plains of China. It provides crucial staging and wintering habitats for a large variety of endangered waterbirds. However, this unique wetland has suffered from serious habitat fragmentation and ecological function degradation caused by increased socioeconomic activities within and surrounding the Nature Reserve. With the aim of enhancing the Reserves ecological function while balancing conservation priorities and indispensable socioeconomic activities, the ecological risks resulting from each three scenario were evaluated. To conduct this research, we developed a systematic framework for ecological risk assessment, in which indices of biodiversity, ecological vulnerability and ecological risk were introduced and employed. Then, an ecological risk assessment was conducted for the scenarios and the pros and cons of each scenario were evaluated based on the applicability of a particular risk in each situation. The results of modeling and assessments provided the basis for adopting wetland restoration scenarios allowing for the development of practical suggestions for wetland restoration and habitat modification.

TiN-Al2O3 bulk composites were prepared by pressureless sintering of the as-synthesized powder products obtained by aluminothermic reduction-nitridation of aluminum dross and rutile. The effects of temperature on the densification behaviour and mechanical properties of TiN-Al2O3 composites were studied. Results showed that the bulk density of the TiN-Al2O3 composites increased with the elevated sintering temperature. When the temperature arrived at 1500 °C, the flexural strength and fracture toughness reached the highest values (201.48 MPa and 4.11 MPa·m1/2, respectively).

In this study the phase behavior of diatomite during magnesiothermic reduction process was investigated. Two packing routes were adopted to estimate the reduction effectiveness at a low reaction temperature of 650 °C for 2h. The phase and microstructure evolution of diatomite were investigated by XRD, SEM, EDS. The results show that diatomite was sucessessfully reduced by the magnesium vapor and reaction products were Si, MgO, and Mg2Si when the raw diatomite was blended with Mg powder. Mg2Si and MgO were alternatively and incompletely dissolved after being immersed in a 1 M HCl solution for 6 h. Meanwhile, the reactant molar ratio had an important influence on products when the raw diatomite was separated with the Mg powder. A small amount of diatomite was reacted to generate MgO and Mg2Si as the molar ratio of Mg and diatomite was 2:1. By contrast, with the molar ratio increasing to be 10:1, diatomite was completely reacted to be Mg2Si and MgO.

The non-sintering Ti (C,N)-Si3N4-SiC composite refractories were prepared using natural quartz, rutile and silicon carbide particles/powders as the raw materials, phenolic resin and urotropin as a complex binder and silicon powder as the additive. The influence of the binder amount on the density, flexural strength, volume shrinkage and the microstructure of the non-sintering Ti (C,N)-Si3N4-SiC composite refractories was studied in detail. The results showed that the amount of binder has significant effects on the properties of the non-sintering Ti (C,N)-Si3N4-SiC composite refractories. The bulk density decreased and the apparent porosity increased as the amount of binder increased, and the flexural strength increased and then decreased as the amount of binder increased, and the volume shrinkage increased with the increase of the amount of binder. The binder is propitious to the properties of the non-sintering Ti (C,N)-Si3N4-SiC composite refractories, but excessive binder will result in the degradation of properties of the as-fabricated composite refractories, the optimum amount of complex adhesive is 15%.

To reveal specific wearing property and principle of polysulfonamide (PSA) blended fabric, this paper aims to make a comparative study of the performance of new PSA blended fabric based on mechanical property, thermal protective performance and, at the same time, explore the performance gap between the different fabrics. Based on the gray fixed weight clustering analysis of gray system theory, several PSA blended fabric have been proved with excellent comprehensive performance, these provided a basis for the selection of thermal protective clothing fabrics.

In the wireless access technology system, reliable and efficient security algorithm is an important guarantee which realizes the high-speed data transmission of LTE (Long Time evolution). The SNOW 3G was used in LTE for its own advantages for security algorithms. This paper describes the procedure of security. Focus on the principle of confidentiality and integrity algorithms of SNOW 3G , then analyses the performance and gets the test result of this algorithms at last.

Simulated Annealing Algorithm is one of the top ten classical optimization algorithm, and it has been successfully applied to various fields. Simulated annealing is a optimization algorithm which can find the global optimal solution, compares to neural network algorithm, it is so easily to implement that has higher probability to be adopted, but it has own shortcomings like other optimization algorithms, its result largely depends on initial value, The initial value of the traditional simulated annealing algorithm began with a random number, its convergence speed is often slow very much and the effect is bad. In this paper, a new simulated annealing algorithm that based on genetic algorithm and hill-climbing method was brought up, because of hill-climbing algorithm was easy to fall into local optimum, and simulated annealing can just solve the problem, it not only escaped from local optimum, but also got good convergence speed and results.

In order to guarantee the high rate, high throughput and low latency and reliable service provided by TD-LTE system under various mobility conditions, handover (HO) procedure and its performance are of high importance. Based on research on structure of TD-LTE system and RRC (Radio Resource Control) layer, this paper proposed intra-system handover procedure in RRC layer of UE side. Simulation of the proposed design and implementation on SDL (Specification and Description Language) /TTCN (Tree and Tabular Combined Notation) verified its conforming to 3GPP conformance protocol specification. Finally, proposed design was verified on the chip ARM1176JZF-S with the corresponding software.

To make sure a good communication between the terminal and the base station, synchronization is needed between them. The Uplink Time Alignment has been provided in the long term evolution system (TD-LTE), by which uplink synchronization can be maintained in terminals. In this letter, the concrete implementation of the Uplink Time Alignment in MAC sub-layer of terminals and independently adjustment of uplink timing were designed with research of the Uplink Time Alignment and detailed analysis of the specific applications of Timing Advance Command in the terminal. The proposed implementation can be applied for the development of test instrumentation and TD-LTE ratio frequency conformance.

In MIMO-OFDM system, the traditional MRC algorithm is used for signal detection in transmit diversity mode ,this algorithm which assumes the same impulse response between adjacent sub-carriers and doesnt consider the noise ,has a higher bit error rate when signal-to-noise ratio is small ,based on this, this paper introduces a fast and effective single tree research sphere decoding detection algorithm and gives a detailed description of the algorithm ,simulation results show that the algorithm can reduce the bit error rate and improve performance.

This paper first introduces the MIMO-OFDM (Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing) system model, and then studies several classical channel estimation algorithms: LS (Least Square) algorithm, LMMSE (Liner Minimum Mean-Square Error) algorithms and SVD-LMMSE (Singular value decomposition) algorithm. Finally, based on the DCT transform domain channel estimation, the original SVD-LMMSE algorithm has been improved. Theoretical analysis and simulation results show that: The improved SVD-LMMSE algorithm not only can reduce the complexity of the implementation, but also has more superior performance.

The presence of the colloid will affect uranium heap leaching. The objective of this study was the examination of the ability of colloid retardation to uranium by irons hydroxide colloids simulated heap leaching process. Batch studies have been carried by observing the effects of pH, contact time, uranium concentration. Iron hydroxide colloids can exist stably at pH 1.5-3.0. The size of the colloid samples is between 20 nm and 1000 nm. The sorption equilibrium was attained at 24 h. The load uranium capacity on iron hydroxide colloids are between 2.43×10-3 and 3.84×10-3 mmol/mol. The colloid morphology of before and after loaded uranium were identified using S-4800 scanning electron microscopy (SEM/EDS). The load uranium capacity on iron hydroxide colloids is least at pH=2, it implies that the appropriate pH of uranium heap leach is 2.0 on the point of retardation of colloid to uranium migration.

This paper summarized and compared the characteristics of trehalose synthase (TS) from various bacteria and the research progress on TS gene engineering. The results show that analysis of TS structure and molecular modification are the research hotspots in TS gene engineering.

A visualization experimental investigation for the pulsating heat pipe (PHP) was carried out to obtain the flow characteristics in the PHP steady operating process with controlling the input heat flux and condensing temperature. The experimental results show that the flow patterns are mainly slug flow with the intermittent pulsation at low heating power, churn flow, and annular flow with steady unidirectional circulation at high heating power. The flow direction switch phenomenon was also observed and analyzed. When the PHP heating section is occupied by vapor slugs for a long time, the backflow phenomenon provides liquid to the bottom of the heating section and reforms a new liquid slug.

This paper investigates methods for multiple attribute decision making (MADM) under hesitant fuzzy linguistic environment. Firstly, we define two transform functions between hesitant fuzzy linguistic variables and hesitant fuzzy variables. Then, based on the presented transform functions, a hesitant fuzzy linguistic weighted averaging (HFLWA) operator and a hesitant fuzzy linguistic weighted geometric (HFLWG) operator are developed, and some desired properties of the operators are also analyzed. Successively, an integrated approach for MADM with attribute assessments taking form of hesitant fuzzy linguistic variables is constructed. Furthermore, an illustrative study on production strategy decision making is carried out to verify the effectiveness and practicality of proposed methods.

Based on previous studies, 130 shallow groundwater samples are collected from Huainan city according to some rules, and 21 indexes of the groundwater samples are tested by different instruments. Moreover, the important works have been done, including statistical characteristics of groundwater components, and divided different types of hydrochemistry, analyses of the relationships between the hardness and Ca2+/Na+, Mg2+/Na+, TDS and the ES. The correlation between heavy metals and conventional components has been discussed. Finally, main components have influence on the quality of shallow groundwater by the method of principal component analysis.

Based on experimental studies, this paper discusses the variation tendencies of three non-dimensional parameters including Ja, Bo and Pr which consist of various operational parameters and characteristic parameters, and then analyses their effects on heat transfer performance of closed-loop pulsating heat pipes (PHPs) at startup stage and steady operation stage. Results indicate that at startup stage, the values of Ja and Bo increase over time as a whole, while the values of Pr decrease; at steady operation stage, the values of three parameters all fluctuate within a narrow range. The results also show that heat transfer is due mainly to the exchange of latent heat under the experimental conditions.

A three-dimensional model of two columns covering hydraulic support was created by Pro/E software. The model was imported into ABAQUS software for finite element analysis. The stresss distribution of the hydraulic support in the conditions of the top beam partial load and the base reversed was got. The result was a reference in the design and structural optimization of the hydraulic support.

The effect of the surface compressive stress (CS) on the wettability of the chemically strengthened glasses on air side and tin side was investigated. The wettability of the air side of the raw glass is better than the tin side. After chemical strengthening, the surface energy of the air side decrease with the decreasing of the CS while the tin side is just the opposite. These results demonstrated that the wettability of the chemically strengthened aluminosilicate glass could be controlled by the compressive stress.

In daily life, lots of work need people maintain higher attention or vigilance. In the early study of vigilance, blink frequency, the impedance of skin, body temperature and blood pressure and other physiological signals was used to estimate the vigilance. EEG signal can more directly reflect the brain's activity than other physiological signals, and EEG signal have a higher time resolution. In this paper, ERP component was used to analyze the alert state, according to this study, the use of ERP component analysis can reflect the subjects’ alertness.

Morphology and characteristics of bubbles have an important effect on engineering applications of gas-liquid two-phase flow. To accurately describe the bubble characteristics, the bubble image processing system based on ARM9 is designed. System hardware is constructed with S3C2440 as the core. QT/Embedded and Qtopia are transplanted to the embedded platform, and the image processing application is developed using QT/Embedded, realizing a good human-computer interaction. According to the characteristics of bubble image, image processing algorithms are presented. The System has low power consumption, small size, and a good real-time performance and scalability.

A composite, TiO2/AgY, was prepared by impregnation of tetrabutyl titanate solution on NaY zeolite, subsequent calcination at 500°C and ion-exchange with AgNO3 solution. XRD.SEM, TEM and EDAX were used to characterize the crystalline phase, the particle size of the formed nano-materials and the relative contents of atoms in TiO2/AgY and NaY zeolite, respectively. TiO2 nanoparticles with the size of 5-8 nm were found to form on the external surface of the zeolite. About half of Na+ in NaY zeolite is exchanged into Ag+. The as-prepared material exhibits excellent antibacterial activity and decompose E. coli using ultraviolet radiation as light resource.

Monocrystalline silicon is typical of hard brittle materials, a high surface quality can be obtained in ductile-regime cutting. The success of the turning process depends on optimizing the machining parameters such as the tool edge radius, tool rake angles, depth of cut and cutting speed, etc. In this study, based on the ductile–brittle transition mechanism, the optimization of cutting parameters were determined with the commercial, general purpose FEA software Msc.Marc. The result demonstrates that the value of temperature is minimum when the tool rake angle is in the range of -15º～-30º. Smaller tool edge radius was selected while maintaining quality of tool edge radius and tool life. As long as beyond the range of cutting speed 6 ~ 8 mm/s, smaller residual stress can be obtain.

The performance of a high-field asymmetric waveform ion mobility spectrometry (FAIMS) detector is directly related to the quality of the asymmetric waveform generator. In this paper, we propose a design scheme of a multi-mode asymmetric waveform generator based on the half-bridge architecture, using a direct digital synthesizer (DDS) method to produce a frequency adjustable square wave pulse and half-sine pulse signal. An isolation circuit was combined with a drive circuit through a TLP250 which is a MOSFET driver chip with photoelectric isolation. The frequency of the proposed waveform generator can be easily controlled.