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Dye-sensitized solar cells have better development prospects than silicon cells, and their main structural composition of nanoporous semiconductor films is particularly important. It is the tin dioxide film, and the effect of preparing tin oxide film on dye-sensitized solar cells under different conditions is studied. In this paper, the SnO2 powder was prepared by hydrothermal method, and the experiment was studied by controlled variable method. The properties of the obtained tin dioxide powder were characterized by SEM and three-dimensional ultra-depth microscope and XRD. The XRD diffraction peak is shown as tetragonal phase rutile type SnO2, With the increase of the concentration of tin tetrachloride solution, the coarser the particle size of the tin oxide crystal in the film, the more complicated the surface morphology, so that the specific surface area of the film is larger. At 0.1 mol/L, the surface of the film is a porous structure in the form of a loose sheet is presented. After analyzing the surface microstructure and flatness of the tin dioxide film, it can be concluded that the effect of salt concentration on the specific surface area of the film is extremely large. When the salt concentration is higher or lower, the obtained two the surface of the tin oxide film is relatively flat and has poor performance. When the salt concentration is 0.1mol/L, the surface of the obtained film has a large undulation and a large specific surface area, and the ability to adsorb the dye molecules can be predicted to be the greatest, and the photoelectric conversion efficiency is optimal in the photocatalytic process.

In this paper, the effect of sintering temperature on the interfacial structure of the composite was investigated and three different formulation groups were used to compare the respective properties. To obtain a composite material with excellent interface, the law between reference number and performance is obtained. Through mixing, molding, sintering, sample preparation, scanning electron microscopic observation, energy spectrometer observation and analysis, the following conclusions can be drawn: As the temperature increases, the density and hardness increase. The sample melts at 1500 °C, and there is no specific data. When the temperature reaches 1450 °C, the density and hardness reach the highest. When the formulation is Fe:Al2O3:SiO2=18:1:1 and the temperature reaches 1450 °C, the properties of the sample materials are optimized. The density is as high as 95% and the hardness reaches 42.9HBW.

In this paper, the effect on the properties of alumina/aluminum cermet by changing the sintering temperature, and comparing the advantages and disadvantages of different characterization methods and their application range, it provides a reference for selecting the characterization technology suitable for alumina/aluminum composites.Through mixing, molding, sintering, sample preparation, scanning electron microscopic observation, energy spectrometer observation and analysis, the following conclusions can be drawn: the higher the vacuum sintering temperature, the more aluminum material is melted out of the body to form aluminum balls on the surface, and the green body The more severe the cracking. When the sample is sintered at a temperature of 600 °C, the density is the highest and the appearance is the best. When the molding pressure is 40 MPa and the sintering temperature is 700 °C, the microstructure of the sintered alumina/aluminum cermet is better. It can be seen from SEM and EDS analysis that the particles are continuously distributed and the larger one is metal Al, and the particles are discontinuously distributed and finer is Al2O3.

In this paper, the effect of raw materaisl on the properties of coated Al2O3/Al cermet materials were investigated, the raw materials were prepared via different methods, which provide a reference for obtaining higher performance cermet materials. Through mixing, molding, sintering, sample preparation, scanning electron microscopic observation, energy spectrometer observation and analysis, the following conclusions can be drawn, the density of the cermet material prepared by the mechanical ball milling method (83.5%) is higher than that of the cermet material prepared by the chemical precipitation method (92.8%). It is nearly 10% lower. The alumina particles prepared by the ball milling method are agglomerated, and a large amount of agglomeration occurs in the aluminum, and the composition is very uneven. For materials prepared by the precipitation method, the aluminum oxide is uniformly distributed in the aluminum. The ball-milling powder is used to prepare materials, most of the alumina is in the form of particles, and in the precipitation method. In the powder preparation sample, the thin layer of alumina which forms the same eggshell envelops the aluminum, and the aluminum has a certain liquid phase change. the surface hardness (824HV) of the cermet material prepared by the mechanical ball milling method is lower than the surface hardness (1005HV) of the cermet material prepared by the chemical precipitation method.

Nano-SnO2 is a relatively important semiconductor material. Its crystal structure is unique rutile type. It has the advantages of high conductivity, high transparency and stable chemical properties. It is widely used in gas sensing detectors and solar cells for photoelectric conversion. Applications. In this paper, SnO2 nanofilms with different crystal structures were prepared by changing the three process parameters of salt concentration, reaction time and hydrothermal temperature in hydrothermal method. The samples were tested by scanning electron microscopy (SEM) and three-dimensional ultra-depth microscopy analyzer. As the concentration of the reaction solution increases, the macroscopic thickness of the film gradually thickens, and the three-dimensional structure of the surface changes from flat to coarse to coarse peak. The peak between the peaks first increases and then decreases, and the surface microstructure is The conditions change are not obvious. Through the comprehensive comparison of film integrity and surface area, it is found that the concentration is 0.03mol/L, which is relatively better.

Both alumina and boron carbide have good hardness and strength, and are widely used in production and life, industrial manufacturing, and military defense. However, due to the insufficiency of research at this stage and the lack of technical means, it is difficult to prepare alumina-boron carbide composite powder with good coating and ultra high strength through large-scale batch production. Therefore, this experiment wants to obtain a relatively good performance of coated Al2O3/B4C cermet by hydrothermal method through different experimental parameter ratios. Through the experimental results and analysis, the following conclusions are obtained. The most suitable concentration of aluminum nitrate is 0.1 mol/l. The low concentration affects the formation of alumina particles. The concentration is too high and prone to agglomeration. Through the optimization of hydrothermal synthesis concentration, a composite of Al2O3/B4C composite with good nanoencapsulated structure was obtained. The composite powder was pure in composition and high in specific surface area, which lays a foundation for solving the low-temperature preparation of high-density boron carbide ceramics.

Dye-sensitized solar cells have better development prospects than silicon cells, and the main structural components of nanoporous semiconductor films are particularly important. In this experimental study, we used tin dioxide film and investigated the effect of preparing this film on dye-sensitized solar cells under different conditions. Furthermore, SnO2 powder was prepared through hydrothermal method, and an experiment was conducted through a controlled variable method. The properties of the obtained tin dioxide powder were characterized by SEM, 3D ultradepth microscopy, and XRD. An XRD peak is displayed as tetragonal-phase rutile-type SnO2, and the SEM indicates that the powder grain size is several nanometers. With the increase in reaction time, the film gradually became flat and uniform from only a small amount of powder coating. At the reaction time of 8 days, the integrity and flatness of the film were optimal, and the pore size was uniform. Moreover, the specific surface area was large. In summary, the reaction time of 8 days is suitable for membrane growth.

The construction industry continues to develop and the requirements for cement performance are getting higher and higher. At the same time, in the steel industry, the discharge of steel slag is also increasing. The effective reuse of steel slag has become a prominent problem in the steel industry. . Therefore, it is envisaged to use steel slag as a raw material for the cement production process to produce cement and to produce high-performance cement. The main raw materials of this experiment are steel slag, limestone, sandstone and shale. Through the cement preparation process, the cement is made, and then the cement is made into concrete to test its performance. This experiment mainly studies the sintering temperature and holding time variable. In the experimental test, the analysis and comparison were carried out in five aspects of the degree of macroscopic cracking, particle size, density, microstructure and composition. In the comparison experiment of sintering temperature, with the increase of temperature, the flexural and compressive properties of cement gradually increased. In this test, 1200 °C is the most suitable temperature for the performance of the cement. Through the experimental comparison of different holding time, it is known that with the prolonging of the holding time, the microstructure and actual performance of the cement are continuously enhanced. Comprehensive consideration: the ratio of steel slag in cement ratio is 10%, sintering temperature is 1200 °C, and heat preservation is 2h. The steel slag cement prepared under this condition has the strongest performance.

Given the shortage of energy reserves, new energy sources must be identified. In this regard, improving the efficiency of solar cell conversion and simplifying the solar cell technology have become the focus of research. In this study, tin oxide nanometer thin film was fabricated on FTO conductive glass as photocathode through hydrothermal method. The synthesis condition was regulated, and performance test was also conducted. Results show that the crystallization driving force, crystallization rate, and grain size of tin dioxide crystal increase with increasing alkali ratio, leading to disorganized accumulation of tin oxide. Under prolonged holding time, tin oxide crystal became complete, and the surface area of the crystal increased. The crystallization driving force and rate also increased with increasing salt concentration and accompanied by clutter of tin oxide. The optimized process condition included 1:4 molar ratio of salt to alkali, 0.05 mol/L salt concentration, 200 °C reaction temperature, and 8 days of reaction. The highest specific surface area of the tin oxide nanometer film was obtained under the optimized condition.

YAG materials has a number of unique properties, the application is very extensive. In this paper, the superfine YAG powder materials were prepared by hydrothermal precipitation method. The influence of synthesis process on the morphology of the powder was investigated. The results showed that when the molar ratio of salt to alkali that Y3+: OH- is 1:8, the more uniform morphology of the particles can be prepared, when the molar ratio of salt to alkali is increased, the morphology of the particles will not change. The reaction time is longer, the particle size will be thicker. The smaller the concentration of Y3+ ions is, the larger the particle size will be small. The experimental results show that the rod-like particles have a poly-crystal structure at the reaction temperature of 200°C, reaction time of 2 days and the molar ratio of salt to alkali of 1:8. The diameter of the rod-like particles is most of the powders have a particle size of 1000 nm and a small amount of powder has a particle size of about 5000 nm. The purity of powder is higher through the test of XRD.

Cermet includes the excellent properties of ceramic materials and the advantages of metal materials, so it is an important new engineering material. In this paper, Al2O3-Al cermet is prepared using different molding process via the powder metallurgy method to study the properties of Al2O3-Al cermet. The conclusion are shown the increasing density of Al2O3-Al cermet is not obvious with increasing the forming pressure of cermet body during the initial and late processing, but the increasing density is more obvious under the forming pressure for 20-30MPa. The density of cermet materials are increased with prolonging holding pressure time, the initial increase speed is faster, and the later growth rate becomes weaker. When the molding pressure is 30MPa, the holding time is 10min, the sintering temperature is 900°C, the holding time is 1h, the prepared Al2O3-Al cermet adding sintering aids has a coated microstructure, which indicates that the large number of particles is migrated on the grain boundary. The sample density is 2.26g/cm3, the density is highest, the distribution of Al2O3 and Al phase is the most uniform. The buried sintering method is more suitable for the preparation of Al2O3-Al cermet composites than the nudity sintering method.

Cermet while maintaining the excellent properties of ceramic materials, but also have the advantages of a metal material, is an important new engineering materials. In this paper, Al-Al2O3 cermet is prepared adding different sintering aids via the powder metallurgy method to study the properties of Al-Al2O3 cermet. The conclusions are shown the adding sintering aids can significantly improve the sintered density of Al-Al2O3 cermet. The sintering aiding effect of adding MgO is better than that of SiO2 and Y2O3, and the hardness and the strength of the sample are higher than those of samples with SiO2 and Y2O3, and the densification degree of Al-Al2O3 metal ceramic material is the best, the relative density is 94.8%, the surface hardness is 824HV. The flatness of the surface of the sample adding MgO shows that the bonding strength between aluminum powder and alumina powder is high. The prepared Al-Al2O3 cermet adding different sintering aids have higher density and fewer pores in the microstructure the prepared Al-Al2O3 cermet adding sintering aids has a package structure.

In atmospheric environments, Al2O3 ceramics have good oxidation resistance in water, acid, and other solutions and suitable corrosion medium resistance. Al2O3 ceramics is one of the most widely used engineering ceramics. In this paper, Al2O3/Al cermet matrix composites were prepared by mixing a series of powders with aluminum and alumina powders as raw materials. The interface of Al2O3/Al cermet was observed by scanning electron microscopy. The densification process of Al2O3/Al cermet was then explored from the aspects of formulation, molding pressure, holding time, and sintering process. After mixing and dry pressing, 50 wt% Al and 50 wt% Al2O3 were appropriate for sintering. Following sintering and measuring density, density was improved under 20 MPa with a 20-minute holding time. Through a comparison of the sintering process, the interface structure was observed via scanning electron microscopy, which found that secondary sintering is conducive to improving the density of Al2O3/Al cermet.

Cermet while maintaining the excellent properties of ceramic materials, but also have the advantages of a metal material, is an important new engineering materials. In this paper, Al-Al2O3 cermet is prepared using different molding process via the powder metallurgy method to study the properties of Al-Al2O3 cermet. The conclusions are shown the density of the initial and late increase is not obvious with the cermet body forming pressure increases, but the increase in density of 20-30MPa is more obvious. The density of the cermet material increases with prolonging holding pressure time is shown, the initial increase speed is faster, and the later growth rate becomes weaker. In the different molding pressure, the pressure is 40MPa and 15min, sintering temperature is 700°C and 1h, the sample density is 2.084g/cm3, the highest density, the best performance, aluminum and alumina distribution is the most uniform.

Cermet materials is a important new engineering materials with the advantages of ceramics and metal materials. The Al2O3/Al cermet materials is prepared via the powder metallurgy method, the effect of sintering technology on properties of Al2O3/Al cermet materials is researched in this paper, which lay the base for preparing the high performance cermet materials. The results are shown through the study, the denstity of cermet is increased with an increasing moliding pressure, the sample density is 2.084g/cm3 as the pressure for 40MPa and the sintering temperature at 600¡æ, the density is higher, that is to say it is highest performance, the distribution of aluminum and alumina is most uniform. When the sintering temperature is higher, howerver, the molding pressure is lower, the lower density of the sample is shown, the aluminum is easier to overflow the surface of the sample.

Pd-doped SiO2 organic-inorganic hybrid material (Pd/M-SiO2) was prepared by sol-gel method and characterized by XRD, FTIR spectra and TG/DTG analysis. The most probable kinetic mechanism function, apparent activation energy and pre-exponential factor of the thermal decomposition for Pd/M-SiO2 material were calculated using the combined Coast-Redfern intergral and Αchar differential methods. Pd element in noncalcined Pd/M-SiO2 materials exists in PdCl2 form. FTIR spectroscopy confirmed the existence of hydrophobic Si−CH3 groups. The thermal decomposition process of Pd/M-SiO2 materials can be divided into four stages, with different mechanism functions. The activation energies are 76.37, 146.85, 208.90 and 413.89 kJ·mol−1 for the four stages, respectively, and the pre-exponential factors are 5.04×1012, 7.14×1013, 2.93×1012 and 6.56×1019 s−1, respectively. There is no obvious influence of the existence of metallic Pd0 on the thermal decomposition of methyl.

Superfine alumina has various excellent performance, superfine aluminum often used in metallurgy, aerospace, microelectronics and medicine, so the study of alumina has become a hot research at home and abroad, superfine alumina powder the body needs are also increasing. In this paper, superfine alumina powder were prepared by hydrothermal method, and to study the preparation process. The results show that the fibrous alumina particles gradually becomes granular with the increase of pH of the reaction, pH value of 9 to get a uniform particle size distribution and an average size of small powder particles. As the increasing calcination temperature, the alumina particles gradually grow, the homogeneous superfine particulate alumina powders is obtained under calcination temperature at 950¡æ. The better preferred process is that alkali molar ratio of 1:3, a concentration of 0.3mol/L, the reaction temperature at 200°C, calcination temperature of 950°C.

Alumina ceramics with good mechanical and corrosion resistance, is one of the most widely used engineering ceramics. The aluminum has a high strength, high conductivity, high plasticity, etc. than aluminum ceramics used in more and more industries. In this paper, aluminum and alumina powder as raw material, mixing, forming, sintering and a series of processes for preparing the alumina/aluminum metallic ceramic materials, through performance testing and analysis can be found in the ratio of raw materials 50wt% Al, 50wt % Al2O3 relatively good moldability. After sintering, after measuring the density contrast is found better density in the pressing process pressure of 20MPa and holding pressure time for 20min. By comparing the sintering process, after the interface structure by scanning electron microscopy and found help improve density through the secondary sintering metallic ceramic materials.

Pd/Ag/SiO2 sols and powder materials were prepared by adding AgNO3 and Pd (NO3)2·2H2O into a methyl-modified silica sol. Tetraethylorthosilicate and methyltriethoxysilane were used as the silica precursor for the sol-gel reaction. The obtained SiO2 sols and powder materials were characterized by sol particle size distribution, zeta potential analysis, UV-Vis spectra, Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) measurement. It was found that most of the particle sizes of the prepared Pd/Ag/SiO2 sols are about 2~10 nm with narrow size distribution. The zeta potential of Pd/Ag/SiO2 sol with Pd/Ag molar ratio of 7.5/2.5 presents the highest value. The FTIR analysis substantiates that the Si-CH3 groups exist in the silica network and the formed Pd/Ag/SiO2 sol particles possess linear structure. XRD characterization indicates that the Pd2+ and Ag+ in the Pd/Ag/SiO2 materials had be reduced to Pd0 and Ag0, respectively, after annealed in a nitrogen atmosphere at 350°C.

Cermet while maintaining the excellent properties of ceramic materials, but also have the advantages of a metal material, is an important new engineering materials. In this paper, prepared by calcination of alumina - aluminum metal-ceramic composite material powder, and its characterization as a basis to provide raw materials for preparing high performance metal ceramic material. According to the research, with the calcination temperature is increased, the rate of change gradually increase the weight of aluminum. Calcined at a temperature of 600¡æ, the oxidation of aluminum surface the best. With the firing time increases, the rate of change in the weight of aluminum powder showed an increasing trend. When 8h, oxidation of aluminum surface better. Through this experiment, process optimization can be found in the calcination temperature was 600¡æ, calcination time is 8h, the best coating effect aluminum surface, coating evenly, clean interface, the reaction layer thickness of about 700nm, the prepared package type composite powders the best results.

Metal ceramics are a important new engineering materials with the advantages of ceramics and metal materials. The Al-Al2O3 metal ceramics were prepared via the powder metallurgy methods and characterized in this paper, which lay the base for preparing the high performance cermet materials. Through the results and analysis, the conclusions are shown that the relative density is increased with a increasing forming pressure, the electrical resistivity is decreased with a increasing forming pressure. The relative density is increased with a increasing sintering temperature under 700°C, the relative density decreases with a increasing sintering temperature above 700°C, the electrical resistivity is shown the opposite tendency. Through the optimizing the technological parameter, such as the sintering temperature at 700°C, the forming pressure under 20MPa, the Al content for 75wt%, Al-Al2O3 metal ceramics are successfully prepared with the high relative density and the low electrical resistivity, the relative density is 97.52%, and the electrical resistivity is 101.34Ω·m

To reveal the anti-penetration mechanism of titanium alloys armor quantitively, the volumes of the front crater region, the ductile hole-enlargement region, as well as the back caving region of Ti-6Al-4V alloy and β20C alloy were measured via 3D Optical scanning technology. The experimental results show that β20C alloy, of which the volume fraction of ductile hole-enlargement region is 51%, 10% larger than that of Ti-6Al-4V alloy, presents a better ballistic performance. It is found that the ballistic performance is closely related to the volume of ductile hole-enlargement region and a relatively larger ductile hole is beneficial to improve the ballistic performance. However, the ballistic performance shows no improvement with increasing the volume of front crater region.

MAT224 is a tabulated version of the Johnson-Cook model in LS-DYNA. Compared with the original Johnson-Cook material, MAT224 was developed to simulate the dynamic response of a material by just defining the effective stress as a function of effective plastic strain at different strain rates and temperatures, thus avoiding the tedious parameter fitting procedures in the traditional Johnson-Cook model. However, the stability and precision of solution is strongly dependent on the effective stress versus effective strain curves in MAT224, and unreasonable curve data will lead to warnings or errors in the process of solution. In the current study, a two-dimensional axisymmetric finite element model for the Ti-6Al-4V titanium alloy under dynamic compression was built, and MAT224 was employed. By investigating the effects of the curve numbers, strain ranges, data points, as well as changing tendencies, on the simulation results, the stability and the reliability for MAT224 are systematically studied.

As a new material, the microstructure of β20C titanium alloy can match well with property by forging process. However, the microstructure of billet is inhomogeneous in actual forging. For ensuring microstructures homogenization, two forging processes are designed. Process 1 is large deformation above the phase transition (T=1050°C, 70% deformation) and small deformation in two-phase region (T=860°C~890°C, ≤40% deformation). Process 2 is small deformation above the phase transition (T=1050°C, 40% deformation) and large deformation in two-phase region (T=860°C~890°C, 50%~60% deformation). Then microstructures are observed and dynamic compressive strength and the critical fracture strain of samples are test after solid-solution treatment. It turns out that the homogeneity of microstructure of process 2 is improved by heat treatment. The microstructure is lamellar microstructure with 1650MPa dynamic strength and 15% critical fracture strain through “Process 1 + 840°C 1h/FC” while the microstructure is equiaxed microstructure with 1650MPa dynamic strength and 20% critical fracture strain through “Process 2 + 840°C 1h/FC”. In conclusion, the microstructure of large deformation in two-phase region can accumulate more deformation energy which is beneficial for dynamic recrystallization.

In terms of good optical properties and high thermal stability, Mo/Si3N4/Mo/Si3N4/SiO2 coatings based on metal/dielectric multilayer structure were adapted to the solar selective coating at high operating temperatures. The coatings exhibited high solar absorptance in the range of 0.924 ~ 0.936 and low thermal emittance of 0.114 ~ 0.118. The coatings deposited on quartz substrates were thermally stable up to 625 °C in air for 2 h, while they were degraded at 650 °C from the characterization of the absorptance and emittance. The degradation of the coatings was mainly due to the oxidation of molybdenum in air, which was confirmed by Raman spectroscopy. Compared with the thermal stability in air, the coatings were much more stable in vacuum under high temperature. The remarkable thermal stability of the Mo/Si3N4/Mo/Si3N4/SiO2 coatings in air and in vacuum makes them suitable to be applied at high temperature applications.

In this work, six asymmetric compound parabolic concentrators (ACPC) were designed for concentrating radiation on all-glass evacuated solar tubes (EST). The ACPCs are required to be horizontally oriented in the east-west direction and to collect direct sunlight for at least 6 hrs in any day of a year. The angular dependence of optical efficiency of six ACPCs, identical in the height of both reflectors after the higher reflector being truncated, was investigated by ray-tracing method, and the annual radiation on EST concentrated by ACPCs was estimated based on solar geometry and monthly horizontally radiation. Results shows that the ACPC designed based on “hat shaped” virtual absorber with a V-groove at the bottom of reflectors is the best in terms of the optical efficiency averaged over the acceptance angle, followed by the one designed based on “hat-shaped” absorber without a V-groove at the bottom, and the one designed based on the cover tube of EST is the worst. However, from the point of annual radiation on EST, the ACPC designed based on the cover tube is the best solution, followed by the one designed based on “ice-cream shaped” absorber and the one designed based on “hat shaped” absorber is the worst due to the smallest geometric concentration factor.

In this paper, Orthogonal test is used in combination with numerical simulation to get a comprehensive consideration of the effectors of die radius, blank holding force (PHF) and punching velocity on dust shield forming performance. Optimum forming parameters is obtained to optimize die structure. These results will give reference to drawing process.

Magnesium, as a kind of lightweight engineering material whose reserves is considerable abundant in the earth, is green environment-friendly materials for the 21st century. Magnesium alloys with its proportion of smaller than the advantages of high strength, good thermal conductivity and easy machining, is becoming a hot spot of attention and research. In this paper, the effects of magnesium alloys thermal conductivity and heat diffusivity were analyzed by consulting documents. Researches showed that all effects of the electron or phonon movement had affected thermal conductivity and thermal diffusivity of alloys. Furthermore, the thermal conductivity and thermal diffusivity of rare earth magnesium alloy were summarized by literature data, Researches showed that Add moderate amount of rare earth elements can improve the thermal conductivity and heat diffusivity of magnesium alloys.

Air source heat pump hot water system is a kind of high efficient energy saving technology model, and it has no pollution to the environment. In this paper, a bathroom of one college in Panzhihua area is researched as a project example, and the working principle of air source heat pump hot water system is introduced, furthermore, the system benefit is analyzed. The result proves the air source heat pump hot water system has good economic benefits, energy saving and environmental protection benefits, and it has a broad development space and application prospect in building energy saving.

In this paper, a novel three phase radial driving meshing motor was introduced. The proposed motor translates the electrical energy into the mechanical energy to drive one rotor. Under the driving of electromagnetic force and restricting of the oldham coupling mechanism, the rotor was constrained to move by circle translation and drives the cycloid machine to output big torque. The control method was found, and the flux linkage characteristic was calculated through finite element method; additionally, the static torque was calculated utilizing the magnetic coenergy principle. The theory analysis is identical with the results obtained from the prototype experiments results. The prototype experiment and analysis testify the designed motor.

Laser aided activating TIG welding was called LA-TIG. At first, the surface of weld was melted by the mini power laser protected by oxygen, and then the conventional TIG was used to cover the weld, which achieved the target of the weld with deeper penetration and narrower width. In this article, the weld bead morphology, arc images, microstructures and mechanical properties of laser aided activating TIG welding joint were analyzed. The results shows that the penetration increased significantly, excellent weld appearance and finger shape penetration were gained by laser aided activating TIG welding. It was found that the arc images of the LA-TIG was only the enlarged form compared with which observed in the conventional TIG and the arc constriction was also observed. LA-TIG weld exhibits better mechanical properties than the conventional TIG welding. Thus laser aided activating TIG welding was developed as a novel active welding method.

The generalized model experiments were designed and conducted in the pressure pipeline to investigate the characteristic of sediment incipient motion. There were some differences between the measured sediment critical velocity and the predictive one which was calculated by traditional formulas. In this paper, the analyses of velocity distribution and its corresponding effect on the sediment incipient motion in the pressure pipeline are done. Then, a simple but available formula which is suitable for the prediction of sediment critical velocity in the pressure pipeline is proposed. Finally, this formula is verified by experimental data and good agreements are observed between the recorded data and predictions.

Architecture design is an important part of the top-level system design, which is related to the development efficiency and quality. Description framework is how to describe the ideas and methods of architecture framework, which help relevant system research personnel understand the architecture. This paper analyzes and summarizes the model of the architectural framework home and abroad, combined with the current development of information technology and information system building needs, which uses the ability to guide the construction, and uses the demand to tract the function. Studying process of building the "new three mutual" (NTM) architecture description framework, this paper designed and completed a six-view architecture framework work, which is more responsive to the current needs of information systems development.

According to the characteristics of underwater production facilities manufacturing workshop, controlling the production information platform data stream based on bar code management. Firstly, the business model of workshop is analyzed and the data stream of production process is extracted. Secondly, the product information structure tree is designed to control data flow of production information platform. In this way, the data of production information platform can be guaranteed constraints, integrity and uniqueness. Finally, according to the information related products information structure tree, the bar code rules are makes, ensure the data acquisition of process to be more efficiently and accurately. The production process can be monitored and managed in real-time, the production efficiency is improved.

While the development of automobile has provided convenience to people's daily life and economic activities, vehicle exhaust has also brought serious environmental pollution. The harmful gas produced by cars contains hydrocarbons and hydronitrogens. Among them, acetylene gas which belongs to atmospheric trace gases, cannot be affected by environmental factors. With the theory of tunable diode laser absorption spectroscopy (TDLAS) technique, wavelength modulation and harmonic detecting technique, this system uses the intelligent data acquisition and processing system based on MSP430 to detect acetylene gas in real-time and display the vehicle exhaust. The system has a good stability, high measuring accuracy and long service life. It is cheap and easy to maintain. It realized low power design.

With the boom of modern science and technology, computer and Internet have melted into human’s daily lives; also it has been affecting the traditional teaching modes. By means of computer and multi-media, the traditional English teaching instructions have altered dramatically. This paper mainly introduces what CAE is, the application of CAE in one of approaches to English writing instruction---process writing approach and its function on students’ writing abilities. A quasi-experimental research is designed in the quantitative part of the study including 12 weeks’ intervention. The procedures are pretest, writing instruction, posttest and data analysis. The result from this research indicates that the process approach by means of CAE in writing instruction is an effective approach to improve students’ writing interests and abilities.

Doubly-fed wind power generator takes the largest share of wind energy. However, as the most important part, the speed-up gearbox is easy to be damaged. The existing researches about gearbox faults are mainly about gear fault, the study of bearing fault is relatively less compared with gear fault, expecially for the bearing fault of planet gear. This article presents a typical case of bearing fault about planet gear, which contains the cause of vibration behaviour and the analysis of fault.

The effects of painting ink’s color on UV absorptivity and UV-light wavelength on curing depth in the process of rotating curing are analysed. Aiming at radial uneven curing, the scheme is proposed that using the UV LED with wavelengths of 365nm and 395nm to form a fan-shaped array on cylindrical surface. The curing system can achieve UV irradiance be enhanced gradually along the radial, and the technique problem of uneven curing is solved. The simulation result shows that the curing system meets design requirements on Tracepro.

The strain recovery character and transformation behavior of a TiNi alloy are investigated by means of mechanical testing and DSC measurement before and after vibration. The DSC results show that the second reverse transformation peak temperature of TiNi alloys after vibration under constraint increases slightly during the subsequent heating, and the transformation heat decreases, while the transformation heat of the first reverse transformation increases. After constrained vibration, the first decline of the two-stage recovery strain obtained during the second heating process is obviously smaller than the one without vibration, and the total recoverable strain also decreases. For the prestrained martensitic TiNi fiber after a heating-cooling cycle, the two-way memory strain increases about 1.2% after vibration. All these phenomena are considered to be closely related to the vibratory stress relief during vibration.

Analysis on the energy-saving demand tendency of the current villa consumer groups to the air-conditioning system, propose one plan of VRV air-conditioning and cross-wind system, for a villa in Chongqing as an example, propose concrete implementation in the energy-saving, comfortable aspect, also expound the feasibility of the cross-wind system.

This paper designed a greenhouse environment monitoring platform with characteristic of video surveillance by making full advantages of embedded Linux system and ARM11 chip. Based on embedded Linux and Qt/Embedded, an on-site greenhouse environment monitoring software was developed. It provided a friendly human-machine interface, combined with a variety of network communication technology, analysed the collected data intelligently and finally created optimal environment for crop growth by running Multiple factor coordinated control algorithm automatically. Leveraging the camera and the built-in multi-format codec, a video surveillance system was developed to monitor the crop environment and growth in greenhouse. Thereby, our platform integrated an environment monitoring system and a video surveillance system. The experimental results show that the platform runs stably in parallel, data transmission is highly reliable, the digitalization and visualization of greenhouse is achieved efficiently. The platform has wide application value.