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FBG (Fiber Bragg Grating) is a new type of optical passive device which can be used in sensing field. This paper demonstrates the feasibility and effectiveness of FBG as the new method of strain measurement, and improves the measuring precision. Based on the strain sensing property of FBG, the study adopts the differential method of double FBGs to make temperature compensation, and conduct the contrast experiment with resistance strain chip. The experimental results show that strain measurement based on FBG agrees well with theoretical calculation. The measurement error: no more than 1%, linear fitting correlation coefficient: almost 1, linearity: 0.17%, sensitivity: 7.92, hysteresis error: 0.347%, repeatability error: 0.333%. The results show FBG’s performance are superior to resistance strain chip, especially in aspect of measuring precision. Therefore, we can conclude that FBG is a feasible and effective method of strain measurement.

Because of the narrow condition of bridge approach embankment, the large compacting machines can not use in the embankment construction. The differential settlement between abutment and approach embankment was easy to produce. Coupled with the the structural differences of the abutment and embankment, how to ensure abutment stable and prevent bridge head bump has been an engineering roadblock in the abutment approach embankment filling engineering. The key factor to solve the problem of the roadblock is reducing the horizontal thrust of embankment on abutment and the difference in settlement between road and bridge. Test results showed that liquid fly ash is a new lightweight value material of self-compacting, which has higher strength, stiffness and smaller density. Using liquid fly ash as the bridge-approach embankment filling material can effectively reduce the horizontal thrust of embankment on abutment and decrease its own settlement deformation. ANSYS computational analysis showed that when we use liquid fly ash filling the bridge approach embankment, the horizontal thrust of the same position will increase with the increase of the filling height, and the value is lesser than the horizontal thrust of soil filling subgrade. Pavement settlement increases with the filling height increasing, but it is significantly less than the general soil filling subgrade.

The contact and slide under high pressure between casing and tool joint leads to wear of the casing inner surface in cemented well. The reduced collapse and burst strength of worn casing threats to the safety of oil and gas well. In order to calculate the wear depth and residual strength of the casing wear, the wear efficiency and friction coefficient is measured in the different wear time, the contact force and the rotating speed. The wear efficiency is in proportion to the contact force and the rotating speed. The wear efficiency of P110 casing change from 2 to 4×10-131/Pa. Friction coefficient reaches maximum value under certain contact force and rotating speed. The rotating speed has less influence on the wear mechanism of casing, while the contact force play a greater influence on the wear mechanism.

Using vacuum magnetron sputtering, preparation of diamond-like carbon film by middle transition layer of Ti, TiN and TiAlN, Ti/TiN/TiAlN in preparing multilayer structure of DLC carbon film on stainless steel substrates, research among different coating material of DLC carbon membrane structure, appearance, hardness, the influence of the interface bonding strength and wear resistance, the film contains some carbon chain structure sp3 hybridized carbon content in the highest and the excellent comprehensive mechanical properties of the material of the middle layer. Experimental studies find that Ti/TiN/TiAlN as transition layer DLC carbon film performance is good, obvious anti stripping adhesion properties, can reduce the diamond-like coating system caused by thermal expansion mismatch stress, using Ti/TiN/TiAlN transition layer of the interface bonding strength of the most outstanding in the middle.

In order to analyze the physical and mechanical properties of the stratified mudstone, the specimens are collected from southwest Nanning , Guangxi, China. X-ray diffraction is used to analyze the mineral composition, the high montmorillonite content affects softening and expansion behavior of the mudstone. The strength tests show that the strength of stratified mudstone is low. When weakness layer exists in the mudstone, the strength is controlled by the soft layer. By long-term immersion in water, the strength will be approximately 76% to 85% reduction. The uniaxial compressive strength tests show that the ratio between soft layer and hard layer under natural is 0.17. The ratio between soft layer and hard layer under saturation is 0.10, under air seasoning is 0.42.

Phase transformation of austenite continuous cooling process in low carbon high strength sheet steel has been researched by DIL805 thermal mechanical simulate. The Austenite continuous cooling transformation (CCT) diagram of steel has been determined by dilatometry and metallography. With the increase of cooling rate, ferritic transformation, perlitic transformation, bainite transformation and martensitic transformation have produced in the organization. Mathematical equations of phase transformation point-cooling rate and phase variable-cooling rate have been established and phase transformation model of high fit degree has been gained by regression calculation. The results show that calculated value and experimental value are nearly similar, so the phase transformation model is feasible.

Introduces the structure and main characteristics of high efficiency low resistance cyclone dust removal, the use of fluid finite element analysis software for the internal flow field is simulated. It can be concluded that gas flow in the cyclone separator, pressure field, velocity field, such as distribution, and on the basis of the flow field calculation results for the structure design about analyzed and discussed.

A tensile test on the 18mm diameter (φ18) and 25mm (φ25) GFRP bars was conducted to observe the tensile apparent characteristics and failure strength. The value calculated by failure strength fomula and the experimental value were ,contrasted to study the parameters and value of the strength calculating formula,, and drawn the conclusions as follows: The φ18 and φ25 GFRP bars' failure strength is effected by fiber materials, enhance materials itself and interface performance. The φ18 bars’ failure strength is about 10% higher than φ25 bars’. The deviation between the calculated value and the actual value is more than 30%. k is the correction parameter in theoretical formula, kφ18=0.76, kφ25 = 0.68 is appropriate. Based on statistical intensity distribution model of GFRP bars’ failure strength, reference stresses value of the φ18 and φ25 GFRP bars are different and the diameters of GFRP bars increases to weaken the strength of the composite material. The reducing rate of the reference stresses is significantly affected by the diameters. The diameters effect is greater than the fiber content effect.

Enantioselective partitioning of racemic omeprazole enantiomers was studied using a biphasic recognition chiral extraction system. Hydrophilic hydroxypropyl-ڂ-cyclodextrin in aqueous phase and hydrophobic D-tartaric acid hexyl ester in organic phase as chiral selectors which preferentially recognize (R)-omeprazole enantiomer and (S)-omeprazole enantiomer, respectively. Different experimental variable parameters could affect the chiral extraction efficiency. The largest distribution coefficientskS,kRand separation factorځwere obtained at concentrations o f 0.1 mol/L HP-ڂ-CD and 0.2 mol/L D-tartaric acid hexyl ester, which were 47.38, 58.65 and 1.24, respectively.kRis always larger thankSwhen using different kinds of tartaric acid derivatives as chiral selectors in organic phase. The present study also reveal the mechanism of biphasic recognition chiral extraction forR,S-omeprazole enantiomers.

This study mainly explores local residents’ cognition toward the impact of holding sport events on the environment. The population for this study is 18-65 year-old residents of Neimen, the place holding Song-Jiang Jhen Battle Array event. Out of 400 survey questionnaires distributed during and after the advent of end of Neimen Song-Jiang Jhen Battle Array event, 306 usable responses were received from participants, indicating a high valid response rate of 76.5%. The results show that (1) residents’ gender and educational background do not exert significant differences among cognition toward positive and negative environmental impacts; (2) younger residents are found to show higher cognition toward positive and negative environmental impact; (3) unmarried residents exert higher positive environmental impact than married residents; (4) residents who support future re-organization of this event are proven to have higher positive environment impact cognition than those who do not; and (5) local residents obviously support the re-organization of Neimen Song-Jiang Jhen Battle Array event in the future.

In this study, researchers attempted to understand the types, frequency, and influences of enterprise business risks in swimming pool industry. Meanwhile, it was to explore whether there exist significant differences between different employee characteristics. Questionnaire survey was used to collect data, 304 valid questionnaires were obtained and valid rate was 76%, from employees of swimming pool. The results of this study were as follows :There were eight enterprise business risk types, including financial risk, disaster risk, responsible risk, policy and legal risk, human resource risk, organizational and strategic risk, operational risk, and industrial risk. industrial risk was the highest influence and financial risk was the lowest on business. Difference in employee’s age and educational level were found significant differences on influence eight dimensions of enterprise business risks.

The typical application of ultrasonic tomography is the determination of process parameters like component flow rates and material fractions in industrial environment. Another promising application is non-invasive health monitoring in medical care. Both acoustic attenuation and acoustic impedance inhomogeneity are the main physical quantities that are used to reconstruct the image. When transmission ultrasonic waves are shadowed by hard tissue because of severe attenuation, the reflection mode can be an effective supplement. This paper provides multi-objects reconstruction images by reflection ultrasonic tomography, demonstrating the multi-objects imaging capability of an immersion circular array system. The circular array consists of 36 ultrasonic transducers with 0.5MHz frequency which are ring arranged and embedded in the container wall to serve as both transmitter and receiver. Each time one transducer is fired and in the meantime other transducers are enabled to receive signals. Ultrasonic transmitting, propagating and receiving of the circular array system are simulated by COMSOL Multiphysics® software, after that a series of image reconstructions of the objects with different numbers are obtained through ellipse algorithm.

Compared with the intrusion detection based on pattern matching, the method which is based on model checking can detect the complex attacks. But all of the existing algorithms are used to detect some specific types of attacks. So, we firstly use the Interval Temporal Logic with Past Construct (ITLPC) formulae to set up formal sub-models respectively for the five kinds of attackers, the four kinds of attack processes and the eight kinds of attack effects. According to their universal relationship and the semantic relation of variety of ITLPC logic operators, we obtain the above sub-models together, thus, the universal models described by ITLPC formulae for universal attacks are formed. On this base, we implement an intrusion detection method based on ITLPC for detecting all types of attacks. Compared with the existing methods, the detecting ability of the new method is more comprehensive.

It is essential to accurately predict or model the residual stresses in a material resulting from various manufacturing operations. Numerical methods were used in this study to predict the residual stresses after quenching and cold compression of an Al 7085 forged block. Experimental verification was provided by comparing the measured distortions due to a relaxation of the residual stresses with the predictions obtained by using a simulated stress field. The validation was carried out on a simplified structural part. The measured and simulated distortions were found to be in good agreement with each other. The results indicated that part distortion is attributable to the relaxation of bulk residual stresses.

With the fast development of information technology, various software systems have been widely applied to production lines and office work. A lot of corporate data thus are stored and processed by these systems each day. Therefore, the security of the software systems is closely related to the data security and the core competitiveness of an enterprise. At present, Java becomes one of the most important programming languages of the enterprise application systems. Against its hidden risks that Trojans and Backdoors are easily implanted through decompilation, the author of this paper proposes a security enhancement technique based on JVMTI for Java software to effectively prevent the malicious users’ decompilation through encrypting the bytecode files, thereby enhancing the security of the software.

It is very meaningful to predict the temperature and thawing time during the thawing process of frozen food in production and life, this paper proposes a physical model of cylindrical frozen food during the thawing process, combine the finite difference method with element balance method to solve the thawing time and the temperature at regional center R/2 and boundary nodes. Take the beef as an example for the experimental verification. Through numerical calculation and experimental verification, the maximum error between the theory thawing time and experiment is 8.4%. The results show that: it is highly consistent with the experimental results that using numerical method to predict the thawing time and temperature change curve, at the same time, the temperature maximum error in center area is 1.2°C, the temperature maximum error of R/2 is 0.8°C, the temperature maximum error of the boundary node is 1.5°C, so the numerical simulation in studying thawing of freezing food is fairly reliable.

Highly water-dissolvable Na2SO4 nanorods were prepared by introducing Ca2+ and NO3- as shape-control agents. The diameter of the as-synthesized nanorods was basically in the range of 20-40 nm, and the length was in the range of 500-800 nm. It was also found that Ca2+ can restrict the growth of the nanocrystals on a given face and the NO3- can also selectively adsorb on a given face and favor the growth of the nanocrystals and the Cl- may help to form uniform nanorods. The synthesis procedure was also simple, and the as-synthesized nanorods may provide ideal templates for preparing nanotubular materials.

The influence of annealing temperature on the microstructure, mechanical properties and corrosion resistant of cold rolling zirconium sheet were studied in the manuscript. The experimental results shown that the tensile strength and yield strength of zirconium sheet were decreased and the elongationwas raised with the raising of annealing temperature from 500 °C to 580 °C. The recrystallization are not happened in zirconium sheet at the annealing temperature of 500 °C. Zirconium sheet complete recrystallized and the strength and elongation get a well match at the annealing temperature of 540°C. Zirconium sheet also complete recrystallized at the annealing temperature of 580°C but the crystalline grain has the tendency of growing. The annealing temperature has no effect on the corrosion resistant of zirconium sheet.

This paper aims at the problem that how to elimination the DC component of the MEMS geophone in the acquisition and processing of Seismic signal. Put forward to design a new circuit in the signal handing system. Design a new type of DC elimination circuit to eliminate the DC component through low-pass filter, reverse and other modules. The experiment result shows that, this new DC elimination circuit is easier to realize and has a large advantage than other existing DC elimination circuits.

Based on the single factor analysis, the effect of extraction time, extraction temperature, and solid to liquid ratio on enhancing crude extracts of essential oil yield from Areca catechu L. flowers was evaluated by response surface analysis (RSA). A three-variable, three-level Box-Behnken experimental design (BBD) was applied and the interactions of each factor on the essential oil crude extracts yield were also investigated. The test data were fitted to a second-order polynomial equation using multiple regression analysis and also analyzed using the appropriate statistical methods. The optimal conditions were at 90 min extraction time, 60°C extraction temperature, and 15:1 solid to liquid ratio using petroleum ether with a boiling range of 60~90°C as the extraction agent. Under such conditions, the essential oil crude extracts yield is 2.52% after three runs.

According to the phenomenon that the road would get frozen during the severe cold region in the high latitude area of Inner Mongolia, this paper study on low temperature crack resistance indexes of the asphalt pavement-the bending stiffness modulus, changing rules of stiffness modulus that is the low temperature anti-crack property index of the asphalt pavement, and bending failure characteristic. The rule changes with the density of the commonly used Chlorine salt snowmelt agent changes. Then the paper analyses how does the Chlorine salt snowmelt agent exert influences on the two kinds of aggregates of bituminous concrete. Finally, it is concluded that the snow-melting agent can weaken the performance of the asphalt pavement. The existing snow-melting agent will be replaced by Affordable and efficient pollution-free deicing in the future.

Using municipal sewage treatment plant sludge as the inoculation sludge, anaerobic ammonia oxidation experiment started in a UASB reactor with an effective volume of 3.5L. The experiment lasted 116d, experimental medium term, the system NH4+-N, NO2--N removal rates were above 50%. Changing influent load will cause a greater impact on the reactor, resulting in fluctuations of NH4+-N and NO2--N removal rate. Late, NO2--N / NH4+-N values ​​remain at around 1. The sludge in the reactor changed from gray-brown to pink. The system is more stable for removing NH4+-N and NO2--N.

The characteristics of AJAX technology can read and write data without refreshing the page, so as to relieve the burden of server and speed up the response and shorten the waiting time for customers. The SSH framework is the organic integration of Struts, Spring and Hibernate three technologies. The e-commerce system has good hierarchical coding design thought of MVC system on the Struts2 framework. The paper presents application of AJAX and SSH framework in development of electronic commerce system.

In order to improve the generality and real-time of image matching procedure, Visual Studio 2010 and MATLAB R2009a have been used as the platform to research mixed programming and improved SIFT algorithm. In this method, the advantages of C # and Matlab have been combined to reduce the difficulty of programming and to improve programming efficiency. The results show that, improved SIFT algorithm can greatly improve real-time of matching program while guaranteeing good matching rate, its suitable in real-time applications.

Deficiency of traditional lifting equipment selection among Multi-Rope mining friction hoist mainly displays in: the existence of larger theoretical and practical deviation of skip load. Key components do not match lifting machine. In consistency between design and actual situation, significantly affected the accuracy of the lifting equipment type selection.Therefore according to the working conditions, it has set up some different multiple mathematical models by the stepwise regression method, nonlinear regression modeling method, method of weighted coefficient and other different modeling methods. Design and select the optimal model for user interface screen by using Matlab GUI and access to calculation data and describe the graphic curve for various model result. Calculate the model results and the average error of the standard load and obtain the optimal model. Finally, design out the lifting equipment selection software of different situations such as economic speed, cycle time, single and double skip, which reduce the selection error, tedious calculation, low efficiency. At the same time, it is convenient for user to use and can constantly expand other functions.

Sapphire substrate was treated by SiH4under NH3atmosphere before GaN growth and nanosize islands SiNxmask was formed on the substrate. Properties of GaN films were investigated by high resolution X-ray diffraction, photoluminescence and transmission electron microscopy. The results indicated that the SiH4flow rate is an important factor affecting the size and density of SiNxmask besides SiH4treatment time.The GaN films grown on the SiNx-patterned sapphire substrate revealed an epitaxial lateral overgrowth mode, which affected 3D to 2D growth time and the microstructures of GaN films. The lowest FWHM value of (102) rocking curve was 286 arcsec. as the SiH4flow rate of 0.5sccm, with the calcultated edge-type dislocations density of 4.28×109cm-2.

With finite element simulation method, the fatigue life of vehicle front floor is analyzed in different vehicle wheelbases and velocities, and the washboard enhancement coefficient is calculated, then K-v curve, K-m curve and K-v-m surface are drawn, with which influence of vehicle velocity and wheelbase on washboard enhancement coefficient is studied. The study results show that, when the wheelbase is constant, washboard enhancement coefficient increases first and then decreases with velocity increasing, and reaches peak at a certain velocity; when velocity is constant, washboard enhancement coefficient decreases as wheelbase increasing; when velocity and wheelbase both changes, washboard enhancement coefficient varies in K-v-m surface.

The Auto-Proving-Ground test cant reveal all problems of testing vehicles. Establishing a more suitable and accurate test for reliability index of auto-mobiles has become an important issue. The operating states data of coaches that running from Hefei to Zhengzhou has been collected in this paper, principal component analysis, and clustering analysis were then used to obtain the main factors that necessary for researching intercity bus reliability. The road condition, the ratio of idling, acceleration, deceleration and constant velocity has been determined based on the real drive condition. The acceleration in the y direction also has been taken into consideration when the bus steer. Based on the factors we improve the effectiveness and rationality of tests, which is in favor of building the system of rapid detection and evaluation for vehicles reliability.

In this study, simulated the reservoir conditions of SuiZhong 36-1 offshore field, we did the research on the optimization experiment of injection timing and injection pattern of the binary composite flooding after polymer flooding. After polymer flooding the launching of binary compound system is studied at the different injection timing (namely when the water content ratio is 0%, the lowest point , 70% and 95% after polymer flooding), the results show that the final recovery efficiency is the highest while directly conversion after polymer flooding, followed is conversion while the water content ratio is the lowest ,70%and 95%..Also compared the impact results of injection of binary complex system in different injection ways on oil displacement effect, the result shows that the injection of 0.3 PV binary complex system is better than the system of polymer injection 0.05 PV + 0.2 PV binary compound system + 0.05 PV polymer binary and 0.1 PV polymer + 0.2 PV binary compound system. But the impact of changing injection way on the ultimate recovery is not big, do before and after protection in a polymer slug is more advantageous to control the cost of industrialization, to maximize the overall benefits of oilfield development.

Taking Jin Chuan phyllite tunnel as the research object, and based on numerical simulation of surrounding rock graded III, IV and V, the paper studied the stress characteristics of initial support and four other representative locations such as two arch vault, arch spandrel, arch haunch, and arch foot during and after the process of construction. The paper focuses on the stress characteristics of secondary lining in different locations after stability and the change of stress in different locations of initial lining before and after the secondary lining construction.

In this paper we give a brief introduction of the data mining method used in thermal power system optimization. The issues as well as the influence of energy material property (take coal as example) on performance matching and optimizing of power plant are overviewed. The development of this domain is presented to readers. Finally, we draw several conclusions. First, Data Mining could have a deeply and widely use in optimization of thermal power plant. Second, the energy material property has a deeply impact on the safe operation and economic operation. The investigation is of great necessary.

Solar Building Integrated Technology is an important measure in architecture energy conservation and environment protection. Taking into account of factors of environment, the new LCA model of Solar Building Integrated Technology is set up and then a concept of Environment Impact Payback Time is put forward. At last, an example of a certain solar thermal system is conducted, the final impact value of which is-2382.39Pt, and the Environment Impact Payback Time is 10 years.

With the deepening of smart grid construction, it is necessary to fully study the intelligent response behavior of residential users, enhance the power grid comprehensive service capabilities and meet the requirements of interactive marketing. According to the model analysis of residential customers comprehensive response behavior, we can get the steady-state situation of residents overall responsiveness, which is able to judge the residents responsiveness level. The homogeneity trend of residential electricitys responsiveness is very strong, as a consequence, we should establish adequate incentives to tap the potential responsiveness of the residential users.

This article is based on three-dimensional laser scanning technology for the modeling of a chemical plant piping, scanned point cloud data with a lot of blunders, comprehensive analysis of the point cloud handling characteristics and stage of maturity of two-dimensional graphics. As a result, a concept of transforming the point cloud data with three dimensional to two-dimensional is formed. Then, according to point and circle positional relationship in the same plane, derived an Algorithm about Gross Error Elimination, finally, programming and achieve it.

By SCR test device to study the main factors affecting the SCR DeNOx efficiency of flue gas for glass furnace,and analyzes the relationship between the main parameters and DeNOx efficiency, such as the reaction temperature, NH3/NOx, initial concentration of NOx, and space velocity.In the actual flue gas conditions of glass furnace,there was an optimum working range for the SCR test device. The reaction temperature is 340~400°C,NH3/NOx is 0.9~1.0,space velocity is 4000~5000 h-1. In this condition, the DeNOx efficiency can reach 80%.

Based on the consequences of abundant relevant literatures, this essay expounded the latest mechanical properties research results of the concrete reinforced with CBF and its application on building structure reinforcement studied by the domestic and foreign scholars. Research suggests that the new composite material of concrete reinforced with CBF has many excellent engineering application characteristics such as good crack resistance, durability, permeability resistance, high temperature resistance and fire retardancy. CBF is a kind of good reinforcement materials with so many advantages including simple construction, favorable reinforcement effect and low cost. We can infer that CBF can be widely used in underground engineering port, deep-water wharf, cross-sea bridges and tunnels, cold region and other fields based on the good mechanical properties and durability of the concrete reinforced with CBF in the future.

It is very crucial to analyze the flexural bearing capacity of the steel-high strength concrete composite beams, but the combination on the flange of steel beam and their bearing capacity is limited with certain inevitability,in addition, in the negative bending regions of continuous composite beams, with the constant increase of load, the process of the whole structure will cause damages in the negative moment region. In order to avoid this kind of damages, we must use general finite element program ANSYS to analyze thebearing capacity of the steel and high strength concrete composite beams. Besides further studying the influence factors of bearing capacity, and ensuring the safety of our engineering performance can be in favor of the engineering structure.

After an earthquake event, the spatial distribution of seismic intensity of the event and extremely destructed area could be quickly evaluated by means of the empirical relationship between ground-motion parameters and seismic intensity, which has been proposed for years. This can provide a basis for the government to carry out emergency relief and reasonable distribution of relief supplies. In this paper, the computational methods of instrumental seismic intensity used at home and abroad are briefly introduced. By analyzing the advantages of the methods in the USA and Japan, a relatively simple computational method of seismic intensity is proposed. Firstly, the acceleration time history (Aall) and velocity time history (Vall) of the complete vibration are synthetized by the filtered three-direction acceleration and velocity time histories, and substituted in the empirical formulation. Then, the seismic intensity can be computed by the sorting method. After that, this method is compared with the intensity scale evaluation method and fuzzy algorithm by using the strong motion parameters of Wenchuan earthquake. The results show that the method proposed in this paper is better than the two methods and has certain practical values.

This paper studied the mapping problem for rescue robots based on laser scan matching and extend Kalman filtering (EKF). Because of the non-structural rescue environments, it is hard to extract typical features. Scan matching method based on normal distribution transform (NDT) can avoid the hard feature extraction problem by estimation of the probability distribution of laser scan data. By fusing NDT scan matching with EKF framework, the NDT-EKF SLAM algorithm was proposed, which can effectively and precisely build maps for rescue environment. Experiment results show that NDT-EKF SLAM algorithm is more precise than algorithms based solely on scan-matching.

To resolve the limitation of information safety and transmission speed in existing communication system, it applied the modular design method to design optical-electric combined THz wireless communication system framework, and determined 125GHz carrier frequency. Aiming at the core component optical emitter uni-traveling-carrier photodiode (UTC-PD) in THz wireless communication system, it analysed the relationship between output power, bandwidth and input signal types, and determined the emitter bandwidth by experiment. The result shows that the transmission speed in the system is able to reach 3.0Gbps when BER is less than 10-10.

This paper studies on the stability capacity of E-glass fiber reinforced polymer (GFRP) tubes under axial compression in order to get the formula, which can be applied to structure design. Firstly, on the basis of test data, finite element analysis is carried out and initial geometric imperfection is considered in the models. Then, it's proved that edge-failure criterion is suitable for stability analysis of GFRP slender components by comparison of results derived from several classic formulas. Finally, a modified Perry-Robertson stability formula is proposed so as to ascertain corresponding stability coefficients for GFRP tubes with different slenderness ratio.

AlGaN/InGaN/GaN double heterostructure high electron mobility transistor (HEMT) with In composition from 0.08 to 0.26 were grown by MOCVD. 2DEG density and mobility of different channel In composition were investigated. When In composition below 0.19, 2DEG density increased nearly linearly with In composition, and the mobility decreased a bit. While In composition over 0.19, phase separation became more serious, 2DEG density nearly not changed, and the mobility dropped sharply. A high 2DEG mobility of 1163 cm2/V·s with low sheet resistance of 342Ω/ was obtained with In composition 0.19.

The safety of the water source area is the premise of urban safety and the basis for the sustainable urban development and urban-rural coordinated development. The contradiction between water source area protection and the development of towns in the water source area is increasingly prominent, and the restrictions of water source area protection on the towns in the water source area have seriously restricted the development of towns in water source area. Based on deep analysis of the principal contradictions and problems between urban water source area protection and the development of the towns in water source area, the paper has proposed the spatial planning pathways and the relevant public policy suggestions for the coordinated development of urban water source protection and the towns in water source area.

In this work, a method to eliminate ice on wind turbine blade by using carbon fiber composites was put forward. To prove that this idea is feasible, a carbon fiber composite panel with its ends soaked by the conductive silver paste was fabricated and surface temperature of it at three levels of voltages was measured. The surface temperature of the composite panel increased significantly and finally retained a constant, which shows that the carbon fiber composites can be used to eliminate ice when the glass fabric composite blades are covered by the carbon fiber composites.

The mechanism of TFE-P copolymer peroxide vulcanization in the presence of N, N - meta-phenylene-bis-maleimide (MPBM) was investigated by MDR Rheometer and DSC method. The results show that β-chain-scission reactions are present in TFE-P copolymer peroxide vulcanization, and the rate of β-chain-scission increase in high temperature. MPBM could improve the crosslinking efficiency and crosslinking rate. The mechanism is that TFE-P copolymer-MPBM radicals could form effective crosslinking and decrease the quantity of TFE-P copolymer radicals that would arise β-chain-scission reactions.

In this work, a kind of conductive polymer-silver paste was used to fabricate carbon fabric composite frequency selective surfaces (FSS) with four-legged slot elements. Screen printing and 3D engraving process were carried out to coat the conductive polymer-silver paste onto the carbon fabric preform and sculpt composite panels into composite FSSs, respectively. Free space and finite element methods were carried out to measure and calculate the electromagnetic transmission characteristics of the composite FSS, respectively. The calculated results are in good agreement with the experimental data. The cascaded effect in double-layered FSS were investigated by finite element method and design of experiment technique (DOE).

The present work focuses on improving the treating efficiency of micro-electrolysis, to solve the problem of passivation and compaction, thereby reducing the investment cost, based on researching the characteristics of treating wastewater through micro-electrolysis, a new method, cavitation-impinging stream micro-electrolysis, is presented, then designing a cavitation- impinging stream micro-electrolysis reactor and analyzing the advantageous features of cavitation- impinging stream micro-electrolysis technology in treating organic wastewater.

High quality N-polar GaN films were grown by MOCVD on C-face 6H-SiC substrate etched by KOH eutectics at 300°C for 5min. A 50 nm high-temperature AlN buffer layer was used to release the lattice mismatch stress between GaN and SiC substrate. The N-polar GaN films grow on the C-face 6H-SiC substrate etched by KOH eutectics have a high crystalline quality and smooth surface. The full-width-at-half-maximum (FWHM) of (002) and (102) XRD spectra were 347.4 and 501.5 arcsec., respectively. The root-mean-square (RMS) of 3μm×3μm is 0.666 nm. The luminescence property of the N-polar GaN films was studied. The band-edge emission of photoluminescence spectra was at 364.6 nm with weak yellow luminescence near 560 nm. The stress in the films was also calculated from Raman spectra. The results indicated a tensile stress in the N-polar GaN films, which is mainly caused by mismatch of thermal expansion coefficient between GaN and SiC substrate.

The tissue samples of cisplatin-resistant and sensitive patients with osteosarcoma were obtained through chemosensitivity testing before. The typical one of cisplatin-resistant and sensitive osteosarcoma tissue samples were analyzed by two-dimensional electrophoresis and the relevant differentially expressed proteins were obtained. The sequences of differentially expressed proteins were obtained through the analysis of mass spectrometry technology to be identified comparing with protein databases. It is concluded that there are differentially expressed proteins in tissue of cisplatin-resistant and sensitive osteosarcoma.

The corrosion failure analysis of an SA210 steel used in high pressure evaporator tube is conducted by XRD, SEM, OM. The result shows that the corrosion products in the inner wall of the steel tube is Fe3O4, mainly caused by the residual water in the evaporator tube corroding its inner wall with oxygen after the hydrostatic test of the boiler, finally leading to the corrosion leak of the tube.