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WO3 nanostructure with nanocube morphology was synthesized through acidification of Na2WO4·2H2O, which were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Moreover, the result of the present work implied that the sensor fabricated by nanocube WO3 could detect the level of 330 ppb H2S, which is much lower than the threshold limit value of 10 ppm. Compared with other results, the nanocube WO3 sensor shows higher sensitivity, excellent selectivity and faster response/recovery to H2S. Especially, the best operating temperature of this nanocube WO3 for H2S detection is 100 °C.

We developed a one-pot method for the fabrication of hydrogel-based photonic crystal (PC) materials. An array of monodisperse colloids was self-assembled within a polymer solution, which generates a visible light diffractable photonic mixture. This mixture was molded and gelated into a hydrogel PC material by freeze-thaw treatment. Drug release as well as the structure colour changing properties of the PC hydrogels were discussed, and the experiment results revealed that our one-pot design and the associated modification approach has potential in efficient fabrication of PC materials.

In order to raise up the the rate of multipurpose utilization of rich-silicon iron ore tailing (IOTP for short) and the preparation of ultra-high performance concrete(UHPC for short), the influence rules and mechanism of rich-silicon iron ore tailing powder replacing fly ash in UHPC were studied, the influences of different specific surface area and dosage of IOTP replacing fly ash on its strength and liquidity were tested. Moreover, the pore structure and hydration products morphology of UHPC were tested by MIP and SEM methods, respectively. The results show that when fly ash replaced by IOTP, the liquidity of UHPC will be increased. When alternative content of IOTP is less than 10%, proper specific surface area of IOTP can improve the strength and pore structure, it can get the best result when the alternative content is 5% and the specific surface area is 588m2/kg. However, when alternative content of IOTP is 15% or more, all of these properties of UHPC become worse. It proves that IOTP can be used in the preparation of UHPC and improve the properties of UHPC.

This paper is focusing on the application of BIM and RFID technology in the technical research and development center project of the EPRI of China. Firstly, the paper makes a introduction of BIM and RFID. Secondly, discusses the advantages of these two technologies which applicate in management and maintenance of electromechanical equipment of this project. Finally, make a conclusion that BIM and RFID technology is very beneficial to the management and maintenance of the electromechanical equipment.

This paper is focusing on the influence of BIM to the stakeholders’ decision making for the Commercial Building Green Retrofit. Firstly, the paper discusses the range of retrofit and how its stage should be determined, then, shows the related stakeholders of each stage should be fixed too, finally, this paper discusses the advantage of the BIM technology which applied in the Commercial Building Green Retrofit, and bring forth of the conclusion that BIM technology can make the decision of Green Retrofit more scientific and reasonable.

Based on the C language course characteristics and requirements, adopt the ASP + CSS + DIV design patterns, and adopts B/S mode structure, using MD5 encryption system and overall planning, design and implementation of data. Coupled with Dreamweaver for static web interface design.

Solar greenhouse is a major form applied to the facility agriculture industry of China currently, which has made historical contribution to the insurance of vegetable supply and farmers’ income increase. On the basis of the full study of environmental factors closely related to the growth and development of plants and the status quo of China’s solar greenhouse technology, this paper develops an automatic monitored control system of solar greenhouse environment based on single-chip and king-view, thus realizing the supervision and control over the environmental factor data such as the temperature and humidity of indoor air, humidity of soil and illumination. The test has shown that the designed function of the system has been achieved with stable and reliable operation as well as friendly human-computer interaction interface, so as to meet the requirements of timeliness, stability and reliability of the solar greenhouse supervision system.

Based on Solidworks software, the three-dimensional model of two wheels scooter is set up. The finite element model of two wheels scooter is generated. Finite element analysis of telescopic mechanism of bar on two wheels scooter is investigated. The stress and strain of telescopic mechanism of bar is investigated. The stress diagram and the strain diagram are obtained. The method and the result can be used as a reference of innovative design of two wheels scooter.

Faced with complex electromagnetic environment and varieties of adaptive radar waveforms, radar signal analysis and identification becomes more and more complex. Considering two important physical quantities - time and frequency in modern signal processing methods, this paper proposes that the joint time-frequency analysis (JTFA) method based on fractional Fourier transform (FrFT) and short-time Fourier transform (STFT) is applied to adaptive radar signal processing. The simulation results show that the joint time-frequency analysis method is superior to single short-time Fourier transform, getting a better analysis of results. The joint time-frequency analysis method provides the joint distribution of the time domain and frequency domain for adaptive radar signal analysis and describes the relationship between signal frequency and time.

In order to avoid the over discharge and less discharge situations, improve the coal recovery rate and promote the working environment of workers at the fully mechanized top-coal caving face, experiments for the research of the coal and rock character recognition were carried on underground. Vibration signal at the hydraulic support tail beam and the rear scraper conveyor under different conditions were acquired at the fully mechanized top-coal caving face using the self-developed mine portable data recorder. The time-domain indexes of the vibration signal were analyzed. Results show that the variance, skewness index and kurtosis index changes most obviously under various stage of top coal caving and can be used as the time-domain characteristic indicator for the coal and rock character recognition in the fully mechanized working face.

To MTO on-line manufacturers, one of the most popular time-based competitive strategies is to widely advertise a uniform delivery time guarantee to all the customers. While providing time guarantee can be an effective marketing approach, it is critical for firms to reduce lead time to keep the promise. Decreasing lot size in batching is one of the most important levers to compress lead time in operation. This research expands existing blanket delivery-time guarantee models by integrating operation approach and marketing approach. The online manufacturers guaranteed delivery time model with order batching is established. Some analytic results are provided, and numerical examples are conducted to provide further insight into the problem. The effects of batch processing setup cost, unit inventory holding cost and unit compression cost of transportation time are analyzed. The results indicate that when batch processing setup cost decrease, unit inventory holding cost or unit compression cost of transportation time increase, the online manufacturer should decrease the lot size and shorten the guaranteed delivery time. The customers time and price sensitivities have adverse influences on the manufacturers delivery time decision.

To produce 130MPa reactive powder concrete with iron tailing sands as aggregation in an economic hot curing system, the effects of curing temperature, curing time and curing conditions on the reactive powder concrete was studied, the reasons of the strength of reactive powder concrete in different curing systems has the difference from the submicroscopic structure point of view was analyzed. The results show that use 90°C hot water to cure reactive powder concrete for 48h can lead it’s 28 day compressive strength reaches 140MPa, the flexural strength reaches 28MPa.

Belt conveyor gearbox is one of key equipments in coal mine which makes sure that the coal mine runs continuously and smoothly. Once it has faults, it will greatly influence the production and the benefits of coalmine. What is more, the raw coal cut by shearer could not be transported to the ground and serious accidents may occur. The authors carry out the vibration monitoring trials on belt conveyor gearbox in an underground coal mine using self-developed mining portable vibration recorder and obtain amount of on-site vibration signal. After analyzing the variation trend of the time domain indexes and power spectrum, we find that the gear of the input shaft of the reducer has severe wear and broken gears. Overhaul results verifies the correctness of the above analysis and the validity of the data sampled by the recorder.

With the promotion of IT applications and the rise of Web 2.0, mass users' individual requirements continue to emerge. How to quickly meet increasing development and maintenance requirements has been a critical problem of software development. Is it possible for end-users to develop software This paper chooses Web information systems as the research field, studies the end-user programming technology, and designs an end-user oriented visual domain-specific language VUDSL for university Web information systems. VUDSL programming tools are also implemented, to support end-users without the knowledge of software engineering to develop target information systems by visual programming.

The velocity history of free-surface particle for carbon phenolic composites (density is 1.4g/cm3) is obtained based on the loading technology of the light gas gun, the relationship between the striking velocity of flyer and the spall thickness as well as time is investigated. Besides, spall strength and thickness are obtained by analyzing the samples data and curves. The high pressure physical characteristics, such as type Hugoniot curve and Murnagham state equation for this material, are acquired by analyzing the velocity history of free-surface and spall characteristics. This study provides a methodology to quantify spall and physical characteristics for carbon phenolic composites under tensile wave loading.

By analyzing the interface characteristics and test requirements of certain aeronautic equipment, using PXI instrument as test platform, integrated using SPIB instrument, virtual instrument, simulation technologies, independent developed video output collection equipment, SRU testing equipment modules and other hardware device, developed integrated automatic test equipment which based on PXI and GPIB bus instrument technology, provide airborne work environment for weapons, instrument, electrical, communication, navigation, identification, reactance systems airborne LRU, automatic complete the control, incentive, performance and function test of LRU.

The DOW’s Fire and Explosion Index (F&EI) was used to assess the chemical enterprise production safety risk. This article used methanol synthesis unit as an example, according to the characteristic of the hazardous chemical and process of the fertilizer production, conducted risk evaluation of the production unit by Fire and Explosion danger index evaluation method, and proposed suitable safety protection measures aim at the evaluation results.

A description of the Railway Large Maintenance Machinery (hereinafter referred to the "RMM") failure is presented and the basic principle of the rough sets and attributes reduction is analyzed. The long-distance clustering method is used to transform continuous attributes values to discrete attributes values. The constructor method of distinguish matrix, and the case study of the RMM diesel engine failure detection attributes reduction is given. Distinguish matrix is constructed to achieve attributes reduction, failure diagnosis based on rough set is completed successfully.

Rotating automatic steerable drilling technology is a new automated drilling technology developed in the early 1990s, which is an important aspect of the development of drilling technology in today's world. The basic structure of closed-loop rotary drilling tools is designed and basic structure of hydraulic thrust control system which greatly saves the time for hydraulic oil flowing back into the tank is innovatively designed based on Auto Trak RCLS (Baker Hughes). The structure of closed-loop rotary steering drilling tools, hydraulic thrust control system principle diagram, basic structure of hydraulic thrust control system and basic structure of flow pressure differential control valve and basic structure of oil filter assembly are rendered by AutoCAD drawing software.

The design of racing brake disc is one of the keys of the car braking system. The initial design of brake disc is based on the overall parameters and design requirements of South China University of Technology FSAE racing car. According to the mechanism of friction heat and friction heat distribution, a simple finite element model of temperature field model, boundary conditions and, using Algor to do a simulation of transient temperature field plate, the front and rear brake discs to determine the final size is analyzed.

Along with the development of advanced control system, in order to achieve the goal of low energy consumption, low pollution and high degree of automation, the coordination matching work of the motor driving electric motor car and the car body has a better future. By using GW48 hardware development platform and the SOPC technology of nuclear NiosII in FPGA as the central processing unit, and with the aid of the Avalon the peripheral circuit of the motor driving electric motor car is completely under control. This is a improvement of the classic control of the motor (i.e. based on single chip or DSP motor control). This article introduces the design method of the drive control system for electric motor cars. A function module design is conducted for the hardware part, which includes the PWM module and control module, and the PWM module and the VHDL language program is used to form the interface function module. A overall design discourse is conducted for the the software part, design processes of each function module are expounded in this paper. Finally the experimental results are given and they have been analysed. The experiment proves that the precision of SOPC technology in the application of electric motor drive control is high and the application is reasonable. It may become the trend of the development of the electric motor cars in the future.

The FSC racing pneumatic transmission system of South China University of Technology realize shift semi-automatic, drivers can be more convenient and completed shift operation in a shorter period of time,so as to improve the results of the competition. According to the preset program driving shift cylinderand clutch cylinder ,compressed carbon dioxide under the manipulation of electronic control unit complete whole transmission process. This paper detailed discusses actuator and electronic control unit design process, at the same time on debugging problems arising from the car, put forward the optimization direction of the system.

Context-aware computing is an important aspect of Pervasive Computing, Cyber-physical Systems (CPS), Cloud computing, etc. Recently, few works have been reported on formal approaches for this area. Bigraph was proposed as a mathematical structure that is consist of two graphs, a place graph and a link graph, intended for modeling distributed, mobile systems, etc. Bigraphs and its corresponding Bigraphical Reactive Systems (BRSs) present a modern, graphical structure, algebra calculus for the description of the syntax and semantics of systems in accordance with the orthogonal notions of connectivity and locality. Bigraphs and BRSs have been applied in various areas. Bigraph is used to formalize context-aware models in this paper. Then, we present an approach to check the formal context-aware models. The formalisms and checking are explicitly depicted through a simple but non-trivial example.

With the development of the high-speed railway (HSR) and metro, the metro crossing the HSR in operation usually happened in metropolis. Considering the stability of railway bridge foundation is very critical to the safety of HSR in operation, it is very important to monitor the influence of the construction of metro tunnel. The no.6 metro line of Nanjing city is crossing the railway bridge group, including three HSR lines, Beijing-Shanghai HSR, Nanjing-Anqing intercity railway, and Shanghai-Wuhan-Chengdu railway. A real-time deformation system using sensors with high accuracy and wireless network is designed to monitor the bridge piers, which are adjacent to the metro tunnel and may be affected in the bridge group. The tilt and settlement of bridge piers and horizontal displacement of pier head are considered in this system. The monitoring results show the feasibility of the system and grantee the operation and bridge engineerings safety.

With the development of science and technology, the controller is widely used in various fields, and control performance is also more and more accurate. In recent years, PID technology is thorough research discuss in many fields, and PID are still not thoroughly solved in online and offline optimization problems. Based on this, this paper introduces the PI controller from the two aspect of the parameter design and online optimization, and the introduction of a new method-fuzzy algorithm, to solve the on-line optimization problem of PI controller parameters in the process of PLC designing, and the program is brought into MATLAB software simulation, to prove the correctness of the program. Finally, this paper presents PI controller with some deficiencies, and provides theory reference for the PI controller parameters optimization.

This paper describes the principles and methods of specular surface measurement which is based on fringe reflection technique (PMD). This technique is based on incoherent imaging and phase shfit. CCD camera was used to record images of sinusoid fringes pattern which is generated by computer monitor and reflected respectively by reflector tested. The phase of modulated fringes that test the mirror collected by CCD can be obtained through the phase shifting algorithm, and the phase of the reference mirror can be calculated according to the structure, so the altitude difference between the two surface shape mentioned above can be obtained by the phase difference between them. The experiment fit the tested surface by 36 zernike polynomial and substitute the gradient data into equations to obtain the measured surface shaped by the least squares solution.

This article proposed a way to reduce the error in the measurement of object morphology that based on the phase measurement profilometry with Optical Fiber Projection Grating. Some simulation of the actual light intensity distribution need to do first to get the error that caused by the aperiodic fringes, express the errors by phase. After that, compensate for this error based on the actual measurement results. There is a larger improvement in the accuracy of the recovery after the process proposed in this article than before through the simulation. The experiment verifies the correctness of this method through the measurement of given standard parts.

The author presents an approach to assist furniture engineers in generating multi-mode 3D exploded view automatically under the environment of AutoCAD platform. Based on the secondary development of AutoCAD with Visual LISP programming language, the approach proposed in this paper can allow users to generate 3D exploded view interactively, either centring on a fundamental part or just exploding the target parts. The automated procedure for generation of multi-mode 3D exploded view is explained and applied with a wooden armchair taken as example, obtaining feasible solutions.

The treatment efficiency of domestic sewage by the SBR filled with humus soil was investigated and compared with that by the conventional SBR. The results show that the removal rates of organic matters, NH4+-N and TP by the SBR filled with humus soil reach 85%, 83% and 72% respectively. Compared with the conventional SBR, the degradation rate of organic matters is improved, and the addition of humus soil contributes to occurrence of SND, thus the removal rate of NH4+-N is increased. The addition of humus soil shortens the oxidation time of organic matters and the nitrification time of NH4+-N, which can improve the treatment efficiency and reduce the operation cost.

When several ultra-wide band (UWB) communication systems coexist, multiuser interferences (MUI) are unavoidable. To cope with the MUI of UWB systems, the independent of UWB signals are investigated and a novel receiving method is proposed. At first several antennas are utilized to receive the transmitted signals of different UWB users, and the mixture signals are gained. Then the mixed signals are separated by independent component analysis algorithm to recover the transmitted signals of each UWB users. Finally, the information of each UWB users transmitted is demodulated. Computer simulations show that the proposed method can efficiently resist the interference of different UWB users.

The DOA Estimation of the MIMO radar is widely used to determine the position of the objects. Having been considered the multipath communication environment, this paper estimates the DOA information of low elevation targets using beam space MUSIC algorithm based on the model of uniform linear array of MIMO radar. Simulations have shown that the algorithm is effective in the multipath spread environment, and the resolution of the DOA estimation of angular is about 0.5°

Proceeding with eliminating or reducing the faults occurring during the operation of the cable arrangement device for electric scooptrams, this article analyses the fault causes, makes analysis and calculations on the tip relief radius of the screw thread, the shape and abrasive resistance of the spindle shaped block, puts forward the measures on improving the abrasive resistance of the spindle shaped block and meets the operational need of the cable arrangement device.

In order to improve the SINR of the beam-former in the case of DOA mismatch, the paper raises the probability of constraint beam-forming algorithm based on mutative scale chaos optimization in connection with the worst performance of the best sound beam-forming algorithm. By introducing the probability constraints confidence interval and the signal vector error distribution law in the beam-forming, the constrained optimization problem is eventually turned into a nonlinear optimization problem. Then the global optimal weight is searched by the mutative scale chaos optimization method. Simulations have shown that the algorithm can significantly improve the SINR.

Steering system is important to the FSAE vehicle performance. And it’s necessary to optimize the steering trapezoid as well. According to the mentioned problem, the steering trapezoid is designed for the special circumstances of the track in this article. the steering mathematical model is established and optimized using the least squares method in the MATLAB Optimization Toolbox to improve the steering stability of the car. After manufacturing and testing the FSAE car prototype, the experimental and optimal results are compared, which indicates that the design of the steering trapezoid mechanism reduce tire wear and protect good steering and grip performance.

The paper determines the real-time location of and the real-time reasons for equipment failures on the premise of the integration of equipment, through the online detection and the real-time analysis of the vibration abnormities and faults in the driving side as well as the service side of rack of brush roll in the washing groove that lies in washing section 2# of the galvanization unit in a plant, by employing the HP35670A dynamic signal analyzer.

The feces and livestock wastewater is characterized with complicated and high level in pollutant and foul odor, great change with loading. Humus activated sludge process with anaerobic-intermittent aeration mode were adopted to treat feces and livestock wastewater complex. The design and operation result showed that the process could remove effectively high concentration organic matter, TN,TP and SS, no foul gas release in residual sludge and during operation, the system has strong tolerance to the high hydraulic load through adjusting aeration period and reflux ratio. The feces and livestock treatment in China can draw lessons from the Yongin feces and livestock wastewater complex treatment system in Korea

The mechanical behavior of rock interior creep fracture evolution and the state are difficult to observe. Combined with the laboratory rock compressive-creep test, the uniaxial creep numerical test based on FLAC3D was carried out. The different positions of the model displacement, stress, strain and damage zone were analyzed under different loading. The mechanical behavior of evolution process and characteristics of rock creep fracture were revealed under the different loading. The results show that: the data of numerical simulation and laboratory test are identical by comparing with laboratory test, and numerical test on simulated rock creep mechanical behavior evolution and methods is feasible and effective. It is a new method that can improve laboratory test of the microscopic creep, provide basis for evaluation of engineering rock mass stability too.

A promising humus activated sludge process with microorganism cultivation reactor filled with humus soil pellets on the basis of traditional activated sludge technology was developed in Japan and used to improve sewage treatment efficiency. Since 1980s, humus activated sludge process was successfully applied in Shimauchi Housing Complex of Matsumoto City, Yamanouchi Sewage Treatment Center and Sewage Treatment Facility at Nagayoshi Agriculture Hamlet and was applied in more than 200 sewage treatment plants in Korea. The operating results showed that the process has the advantage of excellent pollutant removal performance and sludge dewaterability and no odor release.

The gas-pulverized coal two phase flow law of gas is simulated by the use of the theory of jet after coal and gas outburst. Research results show that as the volume fraction of pulverized coal in outbursts mixture increases, the speed of two phase flow at the exit gradually reduces, jet core length shorter, turbulent longitudinal effect range smaller, jet width narrower. And dynamic head mainly concentrates in the jet core area and its distribution is more uniform in the roadways. The maximum speed of outburst two-phase flow decreases with the adding volume fraction of pulverized coal, that is higher the coal content in outburst mixtures, smaller the maximum speed after outburst. But a high content of coal have higher impact strike force which can cause major damage effect. The research may provide some theoretical basis for setting underground safety facilities, mine personal protection, disaster warning and emergency rescue.

In this work, the core-shell FePt@Fe3O4 nanowires and nanoparticles as a new hard-soft composite magnetic materials were synthetized by reduction of platinum acetyl acetonate and iron pentacarbonyl together in the presence of oleic acid and oleyl amine stabilizers by polyol process. As-synthesized FePt nanowires and nanoparticles with 0.5-3 nm Fe3O4 shell were preparated by controlled addition of excess of Fe (CO)5 into the reaction mixture and air oxidation. The phase analysis, structure, and magnetic properties were determined by X-ray diffraction (XRD), High resolution transmission electron microscope (HRTEM), Scanning electron microscope (SEM) and vibrating sample magnetometer (VSM) techniques.

FePt thin films with perpendicularc-axis orientation have potential for application as magnetic media for data storage, In order to be used as perpendicular magnetic storage media,The chemically synthesized cubic FePt nanoparticles is easier to assembed oriented nanoarray, especially the cubic FePt nanoparticles with shape anisotropy is expected to trigger magnetic anisotropy.In this study we provide a simple method to synthesize single crystalline FePt nanoparticles with cubic shapes.The key factor to formation of cubic morphology is using Mo (Co)6as a reducing agent. As-synthesized FePt nanocubes with size that are close to 7-10nm The self-assembly FePt nanocubes are chemically disordered with face centre cubic (fcc) structure where as after annealing these particles changed to face centre tetragonal (fct) ordered structure. The phase analysis, structure, and magnetic properties were determined by X-ray diffraction (XRD), High resolution transmission electron microscope (HRTEM), Scanning electron microscope (SEM) and vibrating sample magnetometer (VSM) techniques.

Mechanical spectroscopy is a powerful tool for the investigation of molecular dynamics of amorphous polymers over a large temperature range and frequency scale. In this work, by using high precision shear mechanical spectroscopy tool, we have investigated the segmental dynamics from local segmental relaxation to sub-Rouse modes in a series of amorphous polymers. We have demonstrated the existence of sub-Rouse modes slower than the local segmental motion in amorphous polymers. The sub-Rouse modes exhibit a similar change of dynamics at the same temperature TB ~1.2 Tg, as the local segmental relaxation through the temperature dependence of relaxation time and relaxation strength. Furthermore, the crossover relaxation time of the sub-Rouse modes at TB is almost the same for all the polymers investigated, i.e. τα'(TB) = 10-1±0.5 s, which is independent of molecular weight and molecular structure. This remarkable finding indicates that solely the time scale of the relaxation determines the change in dynamics of the sub-Rouse modes. According to the coupling model, the crossover is suggested to be caused by the onset of strong intermolecular cooperativity below TB. Hence the results suggest that the sub-Rouse modes and their properties are generally found in amorphous polymers by mechanical spectroscopy, and reveal the cooperative nature of the sub-Rouse modes.

For the complex environment and multi influencing factor in coalface, Wireless Sensor Networks (WSN) is a effective solutions for the coal face of environmental monitoring and miner positioning. Based on the environmental features of the coalface, a WSN deployment paradigm is proposed in this paper, and the DV-HOP localization algorithm is determined to be the miner location solution. Due to the low accuracy of DV-HOP algorithm on condition of the uneven structure of the coalface WSN and the big distance gap between adjacent node, a RSSI-based weight DV-HOP algorithm is proposed. In this algorithm the hops of adjacent node is weighted by the RSS of flooding packets transmitted between adjacent nodes, which associated the hops with the distance of adjacent nodes. Simulation results show that under the same experimental the accuracy of our algorithm is better than the DV-HOP algorithm, and can meet the requirements of localization on the coalface environment.

The path loss exponent shows the effect of space environment on the RF signals in wireless communication model. In most RSSI based location method the path loss exponent is assigned a fixed empirical value which can not reflect the actual environmental impact of the wireless signal, which lead to low position accuracy and considerable positioning error. Aiming at some complex and rapidly changing environment a path loss exponent dynamic acquired algorithm is proposed, which can calculate the actual path loss exponent with the distance and the RSSI value information between adjacent beacon nodes. On basis of the path loss exponent dynamic acquired algorithm a path loss exponent dynamic acquired based localization algorithm is proposed which can estimate the blind node position with the actual path loss exponent, and can improve the adaptability to the environment of the RSSI location algorithm. The simulation shows that the positioning accuracy of proposed method is significantly improved and the effect of proposed method is more precise than the common RSSI method under the same environment.

The enhancive effects of lactic acid on the antibacterial activities of haw pectic oligosaccharides (HPOS) against the Gram positive bacteria Staphylococcus aureus, Bacillus subtilis and Streptococcus faecalis, were investigated. Both HPOS and lactic acid showed dose and pH dependent antibacterial activity against S. aureus and B. subtilis. S. faecalis was sensitive to the HPOS but was resistant to the lactic acid. The antibacterial activity of HPOS against these three bacteria could be enhanced by co-treatment with lactic acid. The results revealed that HPOS may be useful as a food preservative, and lactic acid was able to enhance the antibacterial activity of HPOS, allowing for a further improvement in its efficiency. This additive effect obtained with lactic acid would likely result in a reduction in the dosage necessary for food preservation.

Lithium carbonate, zinc oxide and silica as the main raw materials, potassium oxide and sodium as flux, phosphorus pentoxide as nucleating agent, the glass in Li2O-ZnO-SiO2 was synthesized by conventional melt cooling method and then converted to glass-ceramics. The crystallization behavior, microstructure and thermal expansion coefficient of the resulting glass-ceramics were investigated by XRD, SEM and thermal performance test. The results show that the Tg of the matrix glass is about 508°C, initial crystallization temperature is about 620°C. When the crystallization temperature ranges from 650°C to 750°C, the main crystal phase is Li2ZnSiO4. Increasing crystallization temperature to 850°C, much cristobalite crystals is formed. Owing to the high TEC of the cristobalite, the glass-ceramics with TEC of 12.27×10-6°C-1 were obtained, which is matched with the TEC of stainless steel SAE 1010.

Based on the finite element analysis, the general mechanical property tests and the CTOD (crack tip opening displacement) test of the penstock in the third deviated hole, the GB/T19624-2004, that is the criterion of safety assessment for in-service pressure vessels containing defects suggested by China, is applied to assess the five weld defects in the penstock, which experienced the failure of the pressure test. The assessment results indicate that 1# defect and 5# defect could be accepted, while the other defects should be repaired. According to the assessment results, the defects over criterion in the penstock must be repaired. After the penstock was repaired, it was checked by the ultrasonic flaw detection again. And the results indicate that all weld joints including circumferential and longitudinal weld joints in the penstock around the pipe close in the third deviated hole are acceptable, what provides a scientific basis for the second pressure test and the safe operation of the High head hydropower station.

The failure process for an extra-long pre-stressed concrete beam under static loads was simulated based on the elastic damage theory with the commercial software ABAQUS. By taking account of the different damage behaviors of concrete under tension and compression conditions, a damage mechanics model with three independent parameters was derived from the elastic damage theory. By combining the proposed damage model with the ABAQUS, the damage model was added to UMAT user subroutine. This method was developed to analyze the failure process of the extra-long pre-stressed concrete beams. The theoretical results show that the proposed damage constitutive model can be applied to describe the damage and fracture behaviors of the extra-long pre-stressed concrete beams.

The safety menace of campus network is demonstrated and its network security is estimated in this paper, then combined with the development trend of future network, the necessity of deep inspection and intrusion prevention in campus network is analysized. Finally it puts forward and discusses thoroughly several representative strategies of disposing deep inspection and intrusion preventing in campus network.

This paper is concerned with the numerical study of active control of interior noise induced by the flexible plates in a coupled enclosure. A cabin-like enclosure with four acoustically rigid walls and two flexible plates is considered. Two types of actuators are used, i.e. acoustic actuators and distributed lead zirconate titanate piezoelectric (PZT) actuators instead of point force actuators. With the control system designed to globally reduce the sound field, different control configurations are considered, including the structural actuator on the incident panel, actuator on the receiving panel, acoustic actuator on the cavity, and their combinations. The effectiveness and performance of the control system corresponding to each configuration are studied numerically, and desirable placement problem of structural actuators in terms of total potential energy reduction are of particular interest.