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Zirconium alloys are mostly served as the cladding materials in water reactors. Corrosion is one of the concerning problems in zirconium utilization. Transition of corrosion occurs every 2~3 μm in thickness, but its mechanism is not confirmed. To study the influence of water chemistry and the mechanism behind transition, a new type of zirconium cladding was tested for three corrosion conditions: the pure water, LiOH solution, LiOH/H3BO3 solution at 360°C/18.6MPa. For all cases, Zr-0.5Sn-0.15Nb-0.5Fe-0.2V cladding had a lower corrosion rate and a longer transition time than N36 cladding. The corrosion results showed that the corrosion rate was the highest and the transition time was the shortest in LiOH solution. Oxide phase information on the oxidized surface was obtained by Raman study. Tetragonal zirconia, embedded in the surface, was found at the beginning of corrosion. As the corrosion time increased, tetragonal phase stress was almost released and the content of tetragonal phase was also decreased to zero at the transition point. Stable tetragonal phase was found on the samples corroded in pure water. However, in LiOH solution, it was eliminated the quickest. The acceleration of transition in LiOH solution is partly resulted from the fast transformation of tetragonal phase. The reason for the longer transition time in N2 cladding can be directly attributed to the smaller decrease of the tetragonal phase.

Thin films of Na2/3Ni1/4Mn3/4O2 were prepared on stainless steel substrates by pulsed laser deposition technique. X-ray diffraction and Field-emission Scanning Electron Microscope results show that the thin film deposited at 750°C is highly preferred orientation with homogeneous nanoscale particles. Galvanostatic charge/discharge measurement results reveal that the reversible capacity retention is 91% after 30 cycles with a high initial discharge capacity of 175.3 mAhg-1 at a current density of 13 mAg-1. It also exhibits excellent rate capability, as the current density increases to 260 mAg-1, about 80% of its initial capacity can be retained. After the high rate measurement, the NNMO electrode can deliver a discharge capacity of 110.4 mAhg-1 when the current density was reduced back to 13 mAg-1.

The MOA is the main lightning protection equipment in power system, The status is generally monitored by online monitoring and offline test in routine maintenance. Traditional MOA live detection requires a lot of wiring, and has operation problems and safety risks. A new distributed MOA online monitoring wireless measurement is presented in this paper, that is, 433M wireless transmission and GPS clock synchronization technology fulfill distributed wireless synchronization measurement in MOA online monitoring device. Focusing on the design principles, implementation methods and the device composition, it is indicated that the wireless synchronization testing result is same with wired synchronization testing result, which can meet the requirements of MOA online monitoring.

In order to raise the efficiency of on-site live detection, we proposed a new study of live detection data management system which based piconet and Electric Power System Secure Access Platform(EPSSAP). Piconet of comprehensive multi professional testing equipments with Bluetooth technology is established to wireless acquisite field testing data. Using mobile APN secure access technology, secure communication between the intranet information system and PC power system is realized. Application of the platform will provide basis for a unified multiple data acquisition system, extend functions of intranet information system, such as data storage, information processing regulate the process of on-site live detection work and improve the efficiency of the use of live detection data.

This paper mainly discussed the process to create finite element model of Y4-68 fan,and also analysis the nature frequency and liner static stress.According to the analysis result to determine the optimized parameters,to prepare for the stage of optimization.

Coil transporters are widely used in rolling production line to transport coils among different positions. Aiming at the inaccurate parking space, low production efficiency, high requirement of working accuracy, inconveniency in repair and other problems during the working process, the running mechanism and lifting gear of the coil transporter have been improved, And the author analyze the structure of the improved body by FEA. The results of the analysis of car body show that strength and stiffness meet the requirements. The general property of the improved coil transporter has been, in a good condition, effectively bettered. It can meet the production requirement and enhance the economic benefits.

This article summarized the general process of parametric modeling and finite element analysis of spur gear,PRO/E used to create parametric model,and Patran used to finite element analysis.Parametric modeling can reduce design period of the similar products,and modal analysis provide the basis for the selection and optimization of gear.

Finite element method(FEM) have been widely used in modern mechanical design,mesh generation is an important part of the finite element analysis,this article discussed the process of mesh generation through two practical cases and put forward some issues we should pay more attention to.

The research makes a heat balance test for the radiator system of the analog power capsule. And it also raises a correction calculation method of the fan in the closed cooling heat balance system for special vehicle and proves it by simulation. The research setting up the simulation test bed of the cooling system, conducting the heat balance test and verifying the validity of the carload test bed. Finally, the closed cooling air volume control precision and accuracy of the measurement system can meet the requirements of engineering application

Lithium secondary batteries using LiNi0.5Mn1.5O4 (LNMO) films as a cathode material were prepared by pulsed laser deposition on stainless steel substrates. X-ray diffraction and Field-emission Scanning Electron Microscope results show that the film deposited at 750°C exhibits good crystallinity with well-defined grains structure. Galvanostatic charge/discharge measurement results revealed that the reversible capacity maintains 116.8mAhg-1 after 100 cycles at 0.5C. It also exhibits excellent rate capability, as the rates increase to 5 and 10 C, about 95.4% and 92.3% of its initial capacity at 0.2C can be retained. In additional, thermal stability of the Al2O3 coated LNMO thin film cathodes were also explored. The high temperature cyclic performance of LNMO thin film electrode was significantly enhanced by the coating.

Based on more than three hundred transformer accidents and some statistics data related, this paper manages to draw a standard classification table of transformer failure. 5 degrees of failure possibilities are classified in the paper: extremely high, high, general, low, extremely low. Besides, 4 major factors that affects risk of transformer failure severity are studied: direct lossmonitoring levelmaintenance cost and maintenance period. Also, failure severity of each risk source are classified into 5 levels: not serious, mild, ordinary, less serious, and serious, and Extensional Analytic Hierarchy Process (EAHP) and Extensional Project Appraisal Methods are used to evaluate the severity of risk of transformer failures. Last but not least, risk matrix has been built and divided into four parts: high risk area, critical risk area, medium risk area and low risk area. On that top, some maintenance strategies are proposed accordingly.

The transformer fault diagnostic method based on Bayesian case library is proposed in the paper. Firstly, a transformer fault case library is established by collecting standard guideline and expert experience. Secondly, by standardizing the states and fault modes in the case library, the method takes the states as inputs and the fault modes as outputs, which are used to train a naive Bayesian network classifier. When it is necessary for a fault diagnosis, the user is expected to input the fault states in order to finalize the correct fault mode with the help of the well-trained classifier. On this basis, and with the details of the fault mode, the method could help to get the fault diagnosis results of the case. Finally, the feasibility and effectiveness of this developed method is illustrated by a numerical example of transformer fault diagnosis on site.

Fujian earth-buildings have much attention of the world for their protection since they have became the world heritage in 2008,and have do various building protection research, but the research of rammed-earth material strength nondestructive testing has not began. Through the research of working principle of the rebound hammer and rammed-earth material mechanical properties, increasing the end of the rod to improve the detection precision. Consult the method of building the testing strength curve for concrete to build testing strength curve of rammed-earth material, lays a foundation of field detection for the earth-building in service, contribute to improve protection measures.

ntelligent transport system that based on Internet of Vehicles is regarded as effective measure to guarantee the safety of highway transport. Anti-worm model in vehicular IOT is constructed based on divide-and-conquer with velocity and the drive velocity of vehicle node as the conversion condition between active and passive anti-worms in hybrid anti-worms. Implement this model on the design of Internet of Vehicles terminal, the simulation results show that this model can make the performance of network improved in highway environment regardless of complex road conditions domain and provides a theoretical basis for programming real-time detection strategy and preventing worm destructive epidemics in vehicular Internet of things.

This paper presents a uniform algorithm for single-phase and three-phase load flow calculation. Firstly, two iterative equations with static factors are studied for single-phase power flow calculation based on Gauss power flow algorithm. One is used for all PQ nodes iteration similar to the traditional Gauss power flow algorithm, and the other one is exploited for all PV nodes and the slack node, which is a new algorithm studied in this paper. Then, the three-phase power flow iterative equations are studied. Virtual generator nodes are generated so that it is enough to built equations to solve the unknown parameters and each equation has a unique solution. Two iterative equations are studied for three-phase power flow calculation based on the single-phase formulation studied in this paper. The calculation result shows that the algorithm has the advantage of fast calculation speed, reliable convergence and powerful applicability. It has been shown that the algorithm is suitable for online calculation of single-phase and three-phase power system.

With the rapid development of industrialization and urbanization, cities become the centers to address the problem of climate change for China. Binhai New Area of Tianjin city plays an important role to boost the economy of North China according to the long-term development planning of China. It is essential for Binhai New Area of Tianjin to promote energy efficiency and reduce the CO2 emission intensity. The study explores the characteristics of the energy consumption, energy intensity, carbon emission and carbon intensity of Binhai New Area through time series analysis. We conclude that the consumption of energy has increased with an annual growth rate of 17.9% from 2000 to 2009. The energy consumption per capita increases from 4.32 tons of SCE per capita in 2000 to 12.37 tons of SCE per capita in 2009, which is much higher than that of Tianjin city and also China as a whole. The energy intensity has declined from 0.79 tons of SCE/104Y in 2000 to 0.38 tons of SCE/104Y in 2009. But it is lower than that of Tianjin. Total carbon emission has increased by 225% from 2000 to 2009. The carbon emission per capita increases from 10.8 tons per capita in 2000 to 30.8 tons per capita in 2009. The carbon intensity has declined from 1.97 tons /104Y in2000 to 0.96 tons/104Y in 2009. Thus, we suggest that the composition of energy consumption should be optimized and more clean energy should be used to reduce the total CO2 emission and CO2 emission intensity.

A thermal performance mathematical model of Trombe wall combined with solar air collector was established on the base of thermodynamics and fluid dynamics analysis. Then we solved the mathematical model by means of calculating program based on C programming language. The calculating results show the influence law of the area ratio of air opening to air flow channel (Ao/Af ) and the thickness of air flow channel affected on the heat collecting efficiency of solar wall. With the increasing of Ao/Af , the efficiency increases firstly, then increases more slowly, and finally comes to steady. The thickness also affects the efficiency in the same way. Though the results still need a further validation by experiments, they are initially proved correct by the qualitative analysis. The theoretical model can be a tool for the structural optimization of the Trombe wall combined with solar air collector.

This paper presents a wavelet packet selective algorithm to suppress the radio frequency interference (RFI) in the step-frequency ground-penetrating radar (SFGPR). Based on the property and the form of RFI in the frequency domain of radar echo, the methods of RFI suppression are studied, and the new algorithm is proposed. Using the new algorithm to suppress the RFI in experimental GPR data, the result of the experimentation shows that the algorithm can effectively suppress the RFI in SFGPR. Finally, the performance of the algorithm is analyzed and evaluated. Compared with the median filter algorithm, the ability of the new algorithm to suppress the RFI is significantly improved.

Research was done on durability of two common kinds of carbon fiber reinforced polymer (CFRP) sheets. Eight groups of 40 sheets were tested in recent 3 years. Influence to strength, extensibility and modulus of CFRP sheets was investigated in nature aging environment of east China. Results indicate that strength、young’s modulus and extensibility of CFRP sheets deteriorated owing to climatic factors. An average value of aging residual strength semi-experienced math model is used to study time-dependent deterioration on fiber reinforced polymer affected by climatic factors of east China. Nonlinear fit parameter is used in retain rate curve equation to predict service life of CFRP. Further research is still going on.

With the aim of energy-saving and environment protection, Chinese government and energy consumers are focusing on energy recovery from municipal reclaimed water using the heat pump during building heating and cooling. Municipal reclaimed water assembled in treatment units need to be transmitted to satisfy remote heating and cooling demands in large-scale utilization projects, and transmission distance between treatment units and energy consumers is an important problem greatly affecting the efficient and economic performance of a municipal reclaimed water source heat pump system. Three key problems depending on transmission distance were analyzed. Reclaimed water temperature variation along the delivering pipeline was discussed in consideration of the mutual influence between the transmission medium and the circumjacent soil. Energy consumption of the transmission process was calculated based on pipeline frictional resistance, transmission energy consumption ratio was proposed as an evaluation index reflecting the system energy-saving rate; the transmission distance influence on economic performance was evaluated by dynamic investment payback period and internal return rate. A comprehensive model to determine the transmission distance was presented, which can provide a theoretical analysis tool for system design.

This paper takes metal-insulator-metal system as example and investigates the main types of electrical contact through the view of energy band structure, to analyze the whole process of the transition from ohm contact to barrier contact. Ohm contact, which promotes charges injection from electrode (metal) to insulator, can be used as storage of charge carrier, which is body limited; it can also be regarded as a type of contact that forms an accumulation layer extending from the interface to the interior of the insulator. Whereas, barrier contact is a type of contact which forms a depletion region extending from the interface to the interior of insulator. As for this type of contact, electron injection from metal tends to the state of saturation. The characteristic of neutral contact is that there is no space charge in the insulator, nor band bending, which means the boundary of conduction band and valence band up to the interface is flat.

Three different chemical reductions are used to synthesize spherical silver particles with different sizes. The results show that the sizes of silver particles by glucose、HCOONH4 and NaBH4 reduction are 49nm, 187nm and 37nm and those silver particles with the size below 100nm by HCOONH4 and NaBH4 reduction have narrow size distributions of 30-70nm. In addition, it has been found that adding a small amount of silver nano-particle can improve the conductivity of that whose size surpasses 100nm which is beneficial to the increase of efficiency of the solar cell when adding it into the silver electronic paste.

The wind conditions of the low-rise building in the mountain terrain are different because they have the characteristics of different landforms. When the typhoon comes, the possibility of structural damage is increasing by the negative effects of wind in the special topography. By establishing a sine function of outline of the hill, this paper makes a CFD(Computational Fluid Dynamics) numerical simulation about the low-rise building around the hills with four different height. Using ANSYS-CFX software as calculating platform, it put forward the roof wind load effect of the Low-rise building by study the characteristics of the hill, the law of wind pressure distribution and the influence to roof wind load by wind direction and the high of the hill, the conclusions which can provide a reference for wind-resistant design have practical significance.

As the "Fujian earth-building" have been inscribed by UNESCO in 2008 as World Heritage Site, attentions of protection about the "Fujian earth-building" has getting more and more. This article takes samples of a rammed-earth wall from Yongding earth-buildings and determines the shear strength of the samples with different water content through triaxial compression tests. The influence on shear strength of water content of rammed-earth samples is analyzed. Test results show that the shear strength of rammed-earth has much to do with the water content of the soil, the greater the water content is，the smaller the shear strength is. With water content increasing, cohesion and internal friction angle of rammed-earth were decreases, and its changing trend is of marked characteristic of stage. When water contents of rammed-earth is under some value, its cohesion changes in small ranges; when water contents of rammed-earth is over the value, its cohesion decreases with water content increasing.

In order to improve the utilization of wind energy, set the tower on the roof, the roof tower on the use of CFD technology in different dimensions and different wind direction of the wind environment under the numerical analysis, simulation the velocity field around tower building, and comparative analysis, find out the reasonable fan placed to achieve the purpose of full use of wind energy.

The wind interference characteristic of six buildings in two rows under different spacing (including Sx、Sy ) was Systematically studied by wind-tunnel experiment and numerical simulation. The average wind pressure coefficient and interference factor of the surfaces of each building in the residential district form was obtained, and the results can be provided as reference to the wind-resistant design of residential district.

Since the "Fujian Earth Building" was on the list of the world heritage list, the protecting work of Earth Building gets more and more important. This paper adopts the method combining wind tunnel test and numerical simulation, using CFD software to establish the representative building model of round monolayer Earth Building and get the wind load characteristics in different wind direction. And the wind tunnel tests confirmed the reliability of simulated results. The results provide reference to the protection and wind-resistant design for Earth Building and modern building of Earth Building mode.

The interconnected porous scaffolds are crucial to support the attachment, differentiation, proliferation of cells so to construct 3-dimensional (3-D) tissues. Up to now, there are several approaches to prepare porous scaffolds. In our experiments, we designed a novel porous bioceramic scaffold, called the hydroxyapatite (HA) spherule scaffold, by accumulating HA spherules in an HA porous tube to establish an interconnected porous structure which can be reconstructed exactly. The porous HA tube was manufactured by polymer sponge template while HA spherules were prepared by sol-gel process. In the animal experiment, the HA spherule scaffolds were implanted at 2 different non-osseous sites such as muscle and abdominal cavity in dogs. The new bone growth was investigated after six months. The preliminary results demonstrated that the proliferation of osteocytes on the scaffolds in muscle was obviously better than in abdominal cavity, and about ten times more blood vessels (BVs) were appeared in the former site than those in the latter site. This study presents an alternative way to reveal the relationship between the porous structure of scaffolds and ectopia bone growth because the interconnection and porosity can be controlled easily by the size and porosity of HA spherules.

This study was aimed to estimate the cell-activity after culture of the cell-material composite and to evaluate the feasibility of constructing tissue-engineered bone using this novel material. Hollow HA mcirospheres (H-HAMs), porous PLA\HA tube，polyurethane plunger were prepared respectively. Mesenchymal stem cells (MSCs), which were derived from rat bone marrow were utilized as seed cells.Two different methods were used to integrate the seed cells and scaffold materials. Group A: H-HAMs were filled into porous HA tube, and porous polyurethane plungers were used to cover onto the ends of HA/PLA tubes as a whole, Then MSCs were cultured on the composite scaffolds; Group B: MSCs were compounded with H-HAMs completely first, then the pre-seeded composite of H-HAMs and cells was put into the porous PLA\HA tube which was then sealed with the polyurethane plunger. 1,3,5,7 and 9 days after cell-material composites were cultured, the growing status and adhesions of seed cells were observed. The viability of cells was quantified and increased over time in different methods, but was significantly higher in Group B after 9 days of culture. SEM detection revealed that more cells were detected on the PLA\HA tube and the outer layer of H-HAMs; growth of cells was more widespread and more cells were detected on H-HAMs in Group B. However, cells on H-HAMs seem to diminish over time in both groups. As a novel 3-D Hydroxyapatite scaffold, its H-HAMs are more easy to be integrated with seed cells, to be shaped according to clinical needs because of its semi-liquidity. However, the growth of cells especially in the inner core of the integrated material needs further research.

Hollow hydroxyapatite microspheres (H-HAMs) with controlled characteristic mesoporous structure on the shell were successfully fabricated by using core template technology and sol-gel process. The fabrication of H-HAMs mainly included three distinct steps: the preparation of core template spheres of chitin by emulsifying chitin solution in oil, the formation of core-shell composite spheres of chitin-HA/chitin after a layer of chitin/HA solution coated on the surface of chitin core templates by means of a gelling process of chitin solution with the help of water in the cores, and the harvest of H-HAMs through a special sintering procedure to remove chitin. The size and shape of H-HAMs were chiefly determined by the size and morphology of core templates. The thickness of shells was easily controlled by altering water content of the starting template particles, and the characteristic mesoporous structure on the shell was related to the proportion of chitin in the chitin/HA composite solution and the sintering temperature. H-HAMs with characteristic mesoporous architecture on the shell have many potential applications such as used as a carrier for sustained release of drugs in the therapy of hard tissue system.

A porous composite scaffold for tissue engineering had been developed through a novel gel-casting approach with needle-like nano hydroxyapatite (HA) crystallites and chitin. The freeze-dried nano-HA powder was firstly dispersed in the chitin solvent before chitin dissolves in its solvent completely. The composite solution was evenly mixed with a selected porosifier and poured into a mold in which it became a composite gel under the reaction of water molecules in atmosphere. Subsequently, the composite gel was subjected to the simultaneous extraction of the porosifier and chitin solvent in distilled water. After the drying process the porous composite scaffold was obtained. The morphological analysis showed that the manufactured scaffold had uniform and isotropic porous structure with controlled, fully interconnected pores. In vitro experiments indicated that the bone-like apatite layer formed easily on the walls of the porous n-HA/chitin composite scaffold.

Hydroxyapatite (HA) spherulites had been fabricated successfully through a novel approach including chitin emulsion and geletion processes. The freeze-dried nano-HA powder was firstly dispersed in the chitin solvent before chitin dissolves in its solvent completely. The chitin sol containing nano-HA particles was dropped into oil and emulsified making use of liquids immiscibility effect between oil and chitin sol by stirring. The n-HA/Chitin sol spherulites gelled in situ with the existence of water molecules. Subsequently, the spherular gel granules were rinsed in distilled water to leach the solvent and dried in room circumstance. Finally, special sintering routines were carried to harvest spherular HA granules. The size and porosity of HA spherulites were controlled by the rate of nano-HA to chitin, the chitin concentration in the starting slurry, the stirring rate and the temperature of oil etc. In addition porosifier such as sugar was used in order to adjust the macro- and micro-porous structures in the HA spherulites. The morphological observation showed that the HA spherulites had good sphericity and characteristic microporous structure which were favorable for medical application.