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The porous plate is the key part for distributing gas in the fluidized bed, which is subjected pressure, tension and shear from flowing gas and material during work. The porous plate is required to have good mechanical properties. The Monel porous plate was prepared by the powder metallurgy process in this paper. Meanwhile, in order to obtain the status of compressive resistance and shear, the compressive property and the shear property were studied. The results showed that the compressive resistance yield strength was 143MPa and elastic modulus was 18.1GPa at the edge of porous plate. In the central part, the compressive resistance yield strength was 67 MPa, elastic modulus was 8.2GPa and elastic strain range was 3 %.The minimum shear strength was 116 MPa in edge and 87 MPa in the central.

FeCrAl alloy is regarded as the optimization material for coal-gasification purification with high temperature, due to its good mechanical property, oxidation resistance and sulfide resistance. This paper focuses on the effect of preoxidation on sulfidation resistance of porous FeCrAl alloy. The continuous and dense Al2O3 film, which was formed on the surface of porous FeCrAl alloy after preoxidation, can prevent the diffusions of atom S and metal ion and improve the sulfidation resistance.

In order to meet the requirements for the purpose of biological implant materials, analyzes the matching requirements of the compatibility and mechanical properties of titanium foam biological; by powder metallurgy method, using TiH2 powder as raw material, using ammonium bicarbonate as pore forming agent, preparation of titanium foam. The influences of pore forming agent content and particle size, sintering temperature and holding time on the pore structure, pore distribution, pore size and compressive properties of foam titanium were discussed in detail. The results show that with the increase of the sintering temperature and prolonging holding time, titanium foam compressive yield strength and modulus increased; with the increase of the content of pore forming agent, titanium foam compression yield strength and Young's modulus decreased. The preparation of a porosity of 48% ~ 77%, pore size between 300 ~ 500 m, foam pore structure and pore size in micron level through three-dimensional pore, pore size of bio materials meet the requirements. The compressive strength is 98~186MPa, and the young's modulus is 1.6 ~ 6.8 GPa, which matches the strength and the modulus of elasticity of biological implants.

Stone wool external thermal insulation composite system is used more and more in China now. Former studies in China simply consider that water vapour permeability of render coating should be equal to the water vapour permeability of stone wool. Neither is there any necessary indicator for the liquid water (wind-driven rain) for the system. Therefore, an important issue to be solved currently is how to propose reasonable indicators for water vapour and liquid water transfer performance in stone wool system for different climate zones in China. This research studied on the simulation of hygrothermal distribution of stone wool system. Simulations of stone wool systems were done under different outdoor temperature, humidity, wind driving rain and other conditions to analyze the moisture content in each layer of the system. Meanwhile, simulations of different render coating performances were also done to analyze the moisture content in each layer. Based on these, indicators for water vapour and liquid water were proposed, which provides a foundation for the stone wool external thermal insulation composite system standards in China.

In wireless sensor networks (WSNs), estimation of the location of the unknown node based on the average hop distance is an important research problem for range free localization algorithm. As one of the range free algorithm, DV-Hop chooses the average hop distance comes from the nearest beacon, can't reflect the real status of WSNs. We observe that the unknown node can achieve the precise location when one feedback channels are built between the unknown node and the beacons which embedded accurate location. Based on this observation, we propose one improved DV-Hop localization algorithm based on feedback mechanism (FDV-Hop). Using DV-Hop, the unknown node achieves the estimated location, and broadcasts its average hop distance to the beacons. The beacons also use DV-Hop to calculate their location based on the average hop distance from the unknown node. Then the beacons calculate the difference between the estimated location and the real location, and send the difference between them to unknown node with weights setting. The unknown node recalculates its location which involving the difference of location and the weights. The simulation shows that FDV-Hop can reduce the average localization error effectively and keep the localization stable.

The localization accuracy of traditional APIT localization algorithm for wireless sensor network depends on the Approximate Perfect Point-In-Triangulation Test (APIT), and the localization error can be promoted in sparse network. We design one improved localization algorithm (RTD-APIT) based on APIT by using the RSSI and the triangles deformation. RTD-APIT uses the RSSI to improve the APIT for achieving the preliminary location of unknown node, and expand or deform the triangles for solving the Point-In-Triangulation (PIT) problem well and enhancing the localization. Simulation shows RTD-APIT can reduce the localization error effectively, and it also promote the localization coverage.

Mo-Cu alloy with high density can be fabricated at lower sintering temperature by high-energy ball-milling mechanical-alloying method and adding activation element. The rule of change of microstructure and its effect on the thermal expansion coefficient are studied. It is found that the holes in the Mo-Cu alloy sintered at lower temperature disappear, and Mo and Cu distribute uniformly. The Mo particles are fine-grained, and distribute uniformly in the Cu particles using the mechanical-alloying method. The change of thermal expansion coefficient with temperature is in accordance with the effect of adding activation element. There is a minor inflexion in the thermal expansion coefficient curve at 500°C. The change of thermal expansion coefficient with temperature is the same as 95% Al2O3 sealing material. Thus, the thermal property between Mo-Cu alloy and 95% Al2O3 match well.

The olivary flowmeter, a new type of differential pressure flowmeter, was presented. Its pressure loss was explored through experimental research. The experimental medium is diesel. In the condition of the same effective area of circulation, the pressure loss of the olivary and the orifice plate flowmeter was compared. As a result, the pressure loss of the olivary flowmeter is 14.9% of the orifice plate flowmeter at most, 7.2% on average. The olivary flowmeter can reduce energy consumption.

Through analysis of the technology status of the green building in Xi'an area, targeted Raised the technology development strategy of green building to adapt to the characteristics of the region, such as improve local standards of green building technology system, strengthen the propaganda and training on green building knowledge, improve energy efficiency, use of renewable energy, good publicity and promotion of exemplary green building, full application of green building materials, use of non-traditional water sources and recycling water, etc., in order to provide a reference for the development of green buildings in Xi'an area.

The chiller performance decrease with the system operating is inevitable, however, determining how to predict when it will happen, and how to identity the degree of performance decline, it is very important to solve these actual problems for chiller high efficiency operating and daily management. This paper developed a fault diagnosis model based on thermodynamic analysis of chiller’s refrigeration cycle and heat transfer analysis of its heat exchangers, taking three projects which involve different source sinks, namely, air source, ground source and reclaimed water source as cases study, described the fault diagnosis method and implementation steps through these engineering cases, the results show that the fault diagnosis model provides a newly simple and effective approach for chiller operation monitoring.

Power generation performance of a self-excited retarder determines whether the design goal of its braking torque could be achieved. The numerical analysis of transient electromagnetic field took magnetic vector potential as variable and made six reasonable assumptions to simplify calculation. Based on above, definite solution about transient electromagnetic field and the finite element received a detailed description. The external circuit and end effect of the power generation unit were taken into account so as to improve the calculation accuracy. Let the finite element equation and external circuit equation combine to form field-circuit coupled equations and then using Crank Nicolson method established its space-time discrete model. After verification by experiment, theoretical performance of the power generation unit was basically consistent to the experimental result for a 500Nm prototype. This showed that the numerical analysis as well as the model was feasible and the power generation unit could satisfy the requirement of braking unit for excitation current.

Volatile organic compounds (VOCs) are major constituents of the indoor air pollutants. The indoor air quality has caused wide concern for VOCs may affect human health in many ways. The VOCs in general rooms volatilize from building materials, furniture and so on. In print shops the print equipment and materials may produce a large amount of VOCs that may affect the health of the long-term print shop workers. The author has measured the VOC content and the air indexes in a seventy square-meter print shop in Xi’an with comprehensive functions, then, evaluated the pollution and proposed the preventions of the VOC content in print shops.

Energy consumption reference values support the reference data for development of building energy efficiency potential. A uniform split model of energy consumption was established for calculating the item electricity consumption. Item electricity consumption are consisted by the electricity use of air conditioning system (chillers, chilled water pumps, cooling water pumps, cooling tower fans and end-use equipments), lighting system, indoor equipments and service equipments respectively. The data from site investigation was used to calculate the item electric energy use intensities (EUIs) in commercial office building. And these EUIs were used to identify the item energy reference value by two statistical analysis methods. The results show that the quadratic average EUIs which stand for the high level of energy consumption are lower than the mean plus standard deviation (SD) EUIs. Finally, the individual building (EUIs) can be compared with these reference values to evaluate building energy performance. And the item energy reference value is investigated in support of the retrofit of commercial office building.

Natural ventilation is an important role to improve the residential building indoor thermal environment in summer. This paper use Energy Plus to simulate indoor thermal environment and use CFD to simulate indoor air flow for Xi’an residential building, analysis the influence that different ventilation mode for indoor thermal environment factors. Then with the simulated result of PMV-PPD value to estimate indoor thermal comfort. Proved night ventilation is necessary in residential building in Xi’an and effectiveness to improve indoor thermal comfort.

It is widely accepted around the world that degree days should act as the measurement of HVAC energy in a given place. This paper makes use of the temperature data from 1985 to 2004 from 96 meteorological stations in Shaanxi Province. Based on the daily average temperature in some cities, counties and districts in Shaanxi, we work out the degree days. We divide different zones according to the normalized degree days from 1995 to 2004. In this paper, we analyze the distribution of degree days in Shaanxi, the changes in every decade, and the monthly distribution of degree days in Yulin, Yan’an, Xi’an, Hanzhong, as well as the changes of value in 20 years in Xi’an. At last, we figure out that Shaanxi has spread out its terrain in two climate zones: one is the cold zone; the other is the hot summer and cold winter zone. The HDD18 value has declined continuously in 20 years, and it drops 194.8°C•d/10a every year; meantime the CDD26 has ascended by 28.1°C•d/10a. In all the cities, the HDD18 value is the highest in January, and lowest in July. In the past 20 years in Xi’an, HDD18 value has dropped by 25.0°C•d/a, and the CDD26 has risen by 5.2°C•d/a, which are the highest among those cities.

There are serious energy-saving problems in cold region of rural residential buildings. On one hand, it needs the higher levels energy because of the particular climatic conditions, on the other hand, people in cold regions lack of energy-saving consciousness and technology. Through analyzing the rural residential building status and existing energy-saving problems in cold region of China, the author discussed and summarized the energy-saving design methods of rural residential building in cold region from three aspects, including the energy-saving of residential building size design, the energy-saving of building envelope structure design, and use of renewable energy. The research provides a reference for promoting socialism new rural reconstruction in China.

As social and economic development in China，building scale and medical devices have greatly improved in hospitals, and patients and medical staff are requiring a more and more comfortable indoor environment. All these lead to rising energy consumption of hospital buildings. How to save energy and reduce consumption on the basis of keeping medical quality? This paper takes studies on energy consumption of hospitals in Shaanxi province. First of all, questionnaires about energy consumption of hospitals were carried out. Total energy consumption and electricity consumption were analyzed and energy consumption law was summarized. Then, quota principle and quota method of energy consumption were explored, and energy consumption quota of hospital buildings in Shaanxi province was established. This research contributes to energy-saving of hospital building and provides reference for other public buildings in Shaanxi province.

Tin - Titanium alloy has been prepared by powder metallurgy method. By the way of preparing pre-alloyed metal and fully fine to ultra fine powder, optimizing sintering techniques, the Problem of enrichment of titanium from the alloy has been solved, the Tin - Titanium alloy with its homogeneous distribution elements has been made. Then the Tin-titanium strap has been processed successfully. In this paper, the key process to make Ti -Titanium alloy by Powder Metallurgy Method is introduced. The factors which affect the uniform components of the alloy have been mainly analyzed, such as ultra fine powder of pre-alloyed metal, diffusing sinter at lower temperature .etc. The results indicate that powder metallurgy with ultra fine powder additive and diffusing sinter at lower temperature is the efficient method to solve titanium element in the alloy segregate.

To analyze the transient response of transformer windings under very fast transient over-voltage (VFTO), multi-conductor transmission line (MTL) model based on the representation of transformer windings by its individual turns are established. Space discretization is needed for solving the time-domain telegraph equations of MTL. To calculate the voltage distributions along transformer windings, through combining the compact finite difference (CFD) theory and the backward differentiation formulas (BDF). Simulation software ATP is introduced, and the simulation results demonstrate that the proposed approach is feasible.

The numerical calculation model with compound insulation of transient electrical field is established. The types of voltage applied on the valve side winding of the converter transformer are complicated and the insulation is more prominent. So the simplied calculation model of the valve side winding of the converter transformer is established. The distribution characteristics of electrical field of the valve side winding of the converter transformer is analyzed and electric field in different electrical conductivity and permittivity are calculated under AC high voltage, DC high voltage, AC superimposed DC voltage, polarity reversal voltage. Under all kinds of high voltages, the maximum electric field strength is calculated and analyzed. Some important influence factors for electrical field distribution are also discussed in this paper.

A three-dimensional nonlinear elastic-plastic finite element method had been developed to study the bending behavior of piles subjected to axial load and lateral soil displacement. The influence of the lateral soil displacement, axial load level and the cap of piles were studied and variety law of the bending behavior was presented. The study showed that the bending moment increased with the lateral soil displacement. The displacement at the soil surface and the maximum bending moment of pile also increase with the axial load. The cap of piles has a great influence on bending moment and displacement of pile group.

Partial current rules of the National Standard of Fire Code are disjointed from the current development of large commercial building; as a result, part of the design cannot be carried out according to the specifications. The new digital fire control design method can solve this difficulty. This paper is to take a large commercial building as an engineering example, introducing the new design concept of “independent fire protection unit” and “quasi-safety area” to adjust the program; then, on the basis of fire safety engineering principles, it uses the computer-assisted method to predict and assess the dangers of fire and the safety of evacuation, and thus demonstrating the feasibility of this method.

There is abundant renewable energy in Shaanxi province of China. Renewable energy buildings utilization plays a very important role in the sustainable development of Shaanxi Province. Developing scheme for building applications of renewable energy in Shaanxi province was explored in this paper. Distribution and storage of renewable energy in Shaanxi province was introduced firstly. Taking into account of energy requirements and utilization levels, suitable areas were proposed in this paper, where various kinds building application technology of renewable energy can be promoted. The development priorities in building applications of renewable energy were also discussed. Finally, building applications objectives of renewable energy from 2011 to 2015 in Shaanxi province was proposed. This research will provide reference for building applications of renewable energy in Shaanxi province of China.

In rolling system, there are some drive spindles. While simulating rolling processes, these drive spindles need to be merged into one, and the one merged is described by dynamic model module. According to loading state, the working process of drive spindle is divided into normal stage, critical stage, and over loading stage. The syntony strength of drive spindle is judged with material performance and working frequency.

It is proved that a tension peak occurred in the beginning of tension process between two stands by the continuous rolling test. Based on the speed difference, motor rigidity and coefficient of forward and backward slip, the steady equation of the kinematical mechanics is built. The simulation results of the tension formula accorded with the experimental data. The calculation of shock peak provides an important reference for the technology of continuous rolling.