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In this paper, the effect of heat treatment on the microstructure and mechanical properties of a deformed Co-Cr-Ni-W superalloy strip was investigated. The cold-rolled superalloy was annealed at different temperatures 500°C~1240°C for 10min. It was found that hardness increased in the range temperature 500°C~800°C, the annealing had aging strengthening effect, this was due to the fcc~hcp transformation. As the annealing temperature is higher than 800°C, the hardness decreased with the increase of the annealing temperature. There were four inflection points in the influence of annealing temperature on the hardness of the alloy, which were about 800°C,900°C,1050°Cand 1150°C. From 800°C to 900°C, the hardness of the alloy decreased rapidly, recovery and recrystallization was initial. From 900°C to 1050°C, the hardness of the alloy decreased slower, recrystallization was finished and grain growth slowly. The temperature reaches 1050°C to 1150°C, the hardness curve decreased rapidly, carbides dissolution and grain growth was considerable. Above 1150°C, the hardness tended to be stable, the grain growth of the alloy was obvious, and more annealing twins were also formed. As the annealing temperature increased, the tensile strength decreased and the elongation increased. Keywords Cobalt-base superalloy; Heat treatment; Microstructure; Mechanical Properties Yong-Ji Niu,Yue Zhang University of Science and Technology Beijing,Beijing 100083,china; e-mail: niuyongji@163.com Yong-Ji Niu, Zhi-Wei Zhang, Ning An, Yang Gao Beijing Beiye Functional Materials Corproration, Beijing 100192, China

Based on the Paris model of fatigue crack growth theory, the fatigue crack growth behaviour of Center Crack Tension (CCT) specimens of laser melting deposited 12CrNi2 alloy steel is studied by extended finite element method (XFEM). The crack growth rules and fatigue life are analyzed by experiment and finite element simulation. The experimental results are in good agreement with the finite element results, which verifies the accuracy of XFEM method to simulate the fatigue crack growth behaviour of laser melting deposited 12CrNi2 alloy steel components. Based on this, the effects of initial crack direction and load amplitude on fatigue crack growth behaviour are discussed. The results indicate that even if the initial crack direction is different, the crack will finally propagate in a direction perpendicular to the load. With the increase of the load amplitude, the fatigue life of the specimen with initial crack decreases exponentially.

Derrick and substructure is one of rig’s core equipment components, and it is also the most important weight component of rig. The working environment of derrick and substructure is very serious, whose material should has high strength, excellent plasticity, toughness and weldability property. In this paper, the chemical composition, micro-structure, tensile property, impact property, hardness and weldability of high strength pipeline steel with strength grades of X70 (485MPa)~ X100(690MPa) were systematically analyzed. The analysis and study of the service environment of rig derrick and substructure as well as the technical requirements of the material, showed that the performance of high strength pipeline steel was obviously better than that of the same grade high strength low alloy structural steel used in rig derrick and substructure at present, and it can fully meet the technical requirement of rig derrick and substructure. The application of high strength pipeline steel to rig derrick and substructure will improve the service property, optimize the design , and fully ensure the service safety of rig derrick and substructure.

Effect of various silicon sources, such as TEOS, MTES mixed with TEOS and 1,3,5-tris(triethoxymethyl) on SiO2 films was investigated. The synthesized solutions were used as silicon sources to prepare silica-like backbone films. The investigation showed that all precursors can able to produce the flat and uniform films. An FTIR spectrum confirmed the formation of SiO2 in film matrix. The results indicated that the internal microstructure of each film is different. The incorporation of less polar bonds such as F and C was carried out using various Si sources, while the introduction of these sources confirmed through FTIR spectra. Optical properties of the films were carried out by using ellipsometric porosometry (EP) measurement. The leakage current density for the films prepared by using TEOS, MTES and 135TTEB was observed to be 2.8 × 10-7 A/cm2, 2.9 × 10-8 A / cm2, and 4.1 × 10-6 A / cm2, respectively, at 1 MV/cm electric field strength by the IV curves obtained by semiconductor characterization after fabricating MIS devices. The calculated dielectric constants from RI of the deposited SiO2 films were 2.0, 1.9 and 2.5 respectively. When the microstructure of the precursor solution changed, the introduction of atomic morphology or terminal inerted group ratio changed the internal bridging mode of SiO2, and thereby significantly reduced the dielectric constant and improved insulation.

Rapid preparation of nanocrystalline γ-Fe2O3 powder with superparamagnetism was realized by cryomilling commercial Fe2O3 powder using liquid nitrogen. The effects of milling temperature and duration on the grain size, phase and microstructure of the nanocrystalline Fe2O3 powder were analyzed. Magnetic property of the nanocrystalline γ-Fe2O3 powder was also tested by magnetometer at room temperature. The results demonstrate that nanocrystalline γ-Fe2O3 powder with single phase can be prepared rapidly by cryomilling with liquid nitrogen. The mean particle size of γ-Fe2O3 powder can be reduced from 300 nm to 13 nm by cryomilling at −130 °C within 3 hours. The nanocrystalline γ-Fe2O3 powder shows superparamagnetism at room temperature.

Data collected from 24 marine monitoring stations in Luanhekou-Beidaihe ecological monitoring marine area from 1999 to 2014 reveal a substantial change in the nutrient of this region. The content of nitrogenous nutrients has increased, but phosphate and silicate have decreased. The average N:P ratios have increased from 4.951 in 1999 to 47.188 in 2014;while the Si:N ratios have decreased. The nutrient structure has substantially changed over a period of 16 years. Before 2004, phosphate was relative surplus but inorganic nitrogen was relative lack, while relative surplus of inorganic nitrogen and relative lack of phosphate after 2004. The water quality changed from low nitrogen and high phosphorus (before 2004) to high nitrogen and low phosphorus (after 2004).This finding shows that the nutrient structure may be related to anthropogenic influence.

With the development of electroluminescence application on display, the traditional structures are very classic and often monopolized by special companies in the world. Nowadays, technologies have developed very quickly so that lots of countries focus on the nanoink and substrate material. In fact, the process of producing various flexo screen display can be applied into the variable sized consumer packages by other conductive and phosphor printing material. In this paper, two different sequences of printing will be introduced to compare the advanced style on new structure design. This study also attempts to show the referable ways on materials to help optimize ways in electroluminescence application.

This paper proposes a two-step homogenization heat treatment to dissolve the eutectic structure and long period stacking ordered phase (LPSO) formed during solidification into the α-Mg matrix. The microstructure evolution and mechanical properties of Mg–7Gd–3Y–1Nd–2Zn–0.5Zr alloy during the two-step homogenization heat treatment have been investigated systemically. The results reveal that as-cast alloy is composed mainly of α-Mg, (Mg,Zn)3RE, eutectic phase, stacking fault, block-like LPSO phase and square-shaped compounds rich in RE. The HRTEM results suggest that the block-like long period stacking ordered phase in as-cast alloy is 14H-type rather than 18R structure, and the stacking sequences of the 14H-LPSO phase are ABABACBCBCBCAB. After the first step homogenization of 520°C for 48 h, the eutectic structure has dissolved into the matrix, whereas the 14H-LPSO phase remains in the alloy. To further dissolve the LPSO phase into matrix, the second step homogenization of 540°C for 24h was adopted. After the second-step of homogenization, the residual 14H-LPSO phase has dissolved into the matrix totally. The as-homogenized alloy is composed mainly of α-Mg and square-shaped compounds rich in RE. The tensile tests at room temperature (RT) exhibit that the ultimate tensile strength (UTS), yield strength (YS) and elongation of as-cast alloy are 172 MPa, 128MPa and 2.8%, whereas the UTS, YS and elongation of as-homogenized alloy are 253 MPa, 185 MPa and 8.4, respectively.

Pressurizer surge line is one of the key equipments of nuclear power plants. The thermal stratification due to the intersection of hot and cold fluids inside the pressurizer surge line may affect the safe operation of nuclear power plant. In order to investigate the stress distribution and fatigue characteristics of surge line subjected to long-term thermal stratified loadings, a mechanical model of the surge line was established. And then, according to different temperature distribution assumptions, thermal stress analysis and fatigue assessment were conducted. The results show that the maximum stress appears under the load condition with maximum temperature difference, and finer temperature distribution can obtain more accurate stress and displacement results. The maximum value of fatigue cumulative coefficient appears at the junction of straight pipe and elbow with large temperature difference.

Generally nano-SiC particles are difficult to be added into molten aluminum metals because of poor wettability. Nano-SiC particles reinforced A356 aluminum alloy composites were prepared by a new process, i.e., a molten-metal process combined with mechanical stirring at semi-solid state and ultrasonic vibration method. The nano particles were β-SiCp with an average diameter of 40 nm, and pre-oxidized at about 850°C to form an oxide layer with thickness of approximately 3.6 nm. The SEM analysis results show that nano-SiC particles are dispersed well in the matrix and no serious agglomeration is observed. The tensile strength and elongation of the 2wt.% nano-SiCp/A356 composite in as-cast state are 259 MPa and 5.3%, and they are improved by 20% and 15% respectively compared with those of the A356 alloy.

Gear steel is a ferritic steel. In the rolling process, the ideal structure is ferrite + pearlite, and bainite or martensite is not expected. However, due to the high alloy content, the hardenability is good, and the bainite or martensite structure is very likely to be generated upon cooling after rolling. In this paper, phase transformation rules during continuous cooling of 20CrMnTi with and without deformation were studied to guide the avoidance of the appearance of bainite or martensite in steel. A combined method of dilatometry and metallography was adopted in the experiments, and the dilatometer DIL805A and thermo-simulation Gleeble3500 were used. Both dynamic and static continuous cooling transformation (CCT) diagrams were drawn by using the software Origin. The causes of those changes in starting temperature, finishing temperature, starting time and transformation duration in ferrite-pearlite phase transformation were analyzed, and the change in Vickers hardness of samples with different cooling rate was discussed. The results indicate that with different cooling rate, there are three phase transformation zones: ferrite-pearlite, bainite and martensite. Deformation of austenite accelerates the occurrence of transformation obviously and moves CCT curve to left and up direction. When the cooling rate is lower than 1 °C/s, the phases in samples are mainly ferrite and pearlite, which is the ideal microstructure of experimental steel. As the cooling rate increases, starting temperature of ferrite transformation in steel decreases, starting time reduces, transformation duration gradually decreases, and the Vickers hardness of samples increases. Under the cooling rate of 0.5 °C/s, ferrite transformation in deformed sample starts at 751.67 °C, ferrite-pearlite phase transformation lasts 167.9 s, and Vickers hardness of sample is 183.4 HV.

The components of the flux are optimized and the environmental friendly flux withexcellent comprehensive performance is prepared. Then the composition of the solder paste isoptimized to prepare the SMT environmental protection and high efficient lead-free solder paste, andits performance is studied. The results show that the storage stability, printability, weldability andenvironmental protection of the SMT environmental protection and high efficient lead-free solderpaste are good, and the reliability is high. The related technical indexes have reached or superior tothe commercial solder paste, and have reached the commercial level initially.

The simplified model of biochar-bearing iron ore with binder was studied. It was considered a mixture of two types of core-shell particles, ‘iron ore – binder’ particles and ‘biochar – binder’ particles. The expressions to calculate complex effective permittivity and permeability was derived by effective medium approximation (EMA). The corresponding dependencies on volume fraction of iron ore in the mixture are provided.

A rattle-type diamine-functionalized mesoporous silica sphere (DA-RMSS) was fabricated stepwise using a self-templating method through cationic surfactant assisted selective etching strategy. The rattle-type morphology of the obtained DA-RMSS material was disclosed by transmission electron microscopy, while its chemical composition was characterized by CHN elemental analysis, Fourier transform infrared spectroscopy, and solid-state 29Si cross-polarization/magic-angle-spinning nuclear magnetic resonance spectroscopic measurement, which corroborates the successful formation of siloxane network and the incorporation of organic component. Moreover, nitrogen adsorption–desorption isotherm measurement was conducted to reveal that DA-RMSS possesses large Brunauer–Emmett–Teller (BET) specific surface area of 814 m2g–1, pore volume of 0.78 cm3g–1, and narrow pore size distribution centered at 3.0 nm. Furthermore, its uptake property on carbon dioxide was also investigated in this contribution.

This study aims to review variation pattern of moisture content ratio of grains in deep-bed drying process, guide the drying technology design, realize real-time tracking and regulation in drying process, improve the quality of drying process and reduce energy consumption. Based on the moisture diffusion model in thin layer drying process, the principle of mass conservation of deep drying process, state function and irreversible thermodynamics analytic method, we have established and solved basic equations of deep-bed drying of grains, obtained the moisture content ratio of grains and analysis formula of drying velocity distribution in processes of concurrent flow drying, counter flow drying, cross-flow drying and standing drying and resolved the sustained decreasing drying process of grains in the concurrent flow drying and extreme point of drying rate in the counter-flow drying. Under the same conditions of temperature, humidity and air output, the drying velocity in counter-flow drying significantly higher than that in the concurrent flow drying. It means the energy utilization effects in counter-flow drying is better than that in the concurrent flow drying. Drying characteristics of grains in cross-flow drying and standing flow drying are the same, while drying rates in inlet-air side and outlet-air side vary widely. It means that when the layer thickness is 0.5m and the moisture content is over 20%, the drying rate in outlet-air side is nearly zero and the drying uniformity is bad. Tests on 5HP-3.5 recirculation drier shows that maximum deviation between analytic value and measured value in deep drying process is 0.69% and the range scope is -0.27%-0.69%. From the drying characteristics of grains, deviations mainly come from instrument detection deviations. The analytic method has important significance for realizing real-time tracking and regulation in drying process, guiding drying technology design, reducing energy consumption, increasing drying rate and drying machine capacity.

Based on the finite element model of high frequency welded pipe welded of composite aluminum alloy, the stress-time variation curves of welded pipe in different welding parameters were obtained. The analysis shows that the residual tensile stress in the weld zone is largest. At the same time, the weld tensile test and hydrostatic burst test were conducted. When the residual tensile stress in the weld zone is high, the blasting pressure which the weld can withstand is small, and the cracking position is often in the welded seam zone. To a certain extent, the change of the thermal stress in the welding process and the residual stress in the cooling process can be accurately reflected by the finite element analysis method.

A low pass filter based on spoof surface plasma polaritons (SSPPs) was devised successfully, which possessed three-section structure, the microstrip wave guide as the first section, the conversion section as the second section, and the SSPPs as the third section. It should be noted that there is a new V-shaped groove structure in the third section, which were carried out by the simulation on characteristics of stop band rejection characteristic and bandwidth for low pass filter. These results indicated that the low pass filter had Pass-band between direct-current and 7.8592GHz, the pass-band insertion loss was better than -3dB, the pass-band reflection was less than -10dB. This new type of SSPPs low pass filter would be certain engineering value in the application of microstrip circuit, microwave base station and radar microwave communication system between L band and X band.

Copper matrix composites (CMCs) are widely used in electrical equipment and electrical contact materials due to their excellent electrical properties. Al2O3 powders are widely used as a reinforcing agent to enhance mechanical properties of MMCs. The xAl2O3/Cu (x =0, 0.2, 0.5, 0.7, and 1.0wt. %) composites were prepared via vacuum arc melting method. The mechanical and electrical properties were obtained by measuring the hardness and conductivity. The morphology of copper and Al2O3/Cu composites was characterized by optical microscopy (OM) and scanning electron microscopy (SEM). With the addition of Al2O3 from 0.2 wt. % to 1.0 wt. %, the relative densities of composites decreased from 98.5% to 97.0%. The hardness of the composites increased with increase in the Al2O3 powders content. The hardness of 1.0Al2O3/Cu composites was 57.9 HB, which was higher than that of pure Cu by 18.6%.. With the addition of Al2O3, the IACS% of Al2O3/Cu composites decreased from 88.97 to 86.16.

Effects of magnetic field intensity on carbon diffusion in pure iron in paramagnetic ferrite region above the Curie temperature were investigated using carburizing technology. It was found that the magnetic field intensity can significantly affect the carbon diffusion behavior in pure iron in paramagnetic ferrite region in the direction parallel to the magnetic field direction, both the carbon diffusion coefficient and the average carbon diffusion distance increase gradually with the increasing of the magnetic field intensity. Magnetic field annealing obviously promotes the carbon diffusion in pure iron in the direction parallel to the magnetic field in paramagnetic ferrite region above the Curie temperature, and promotion effect increases with the enhancement of the magnetic field intensity. The structure defects made by the magnetic field may cause the increasing of carbon diffusion flux.

In this paper, carbon nanotubes (CNTs) dispersion behavior in epoxy resin under synergistic effect of continuous stretching flow and ultrasound oscillation was studied. A small continuous stretching machine which could provide continuous stretching flow for polymer was designed and manufactured for studying the synergistic effect of continuous stretching flow and ultrasound oscillation on dispersive property. Firstly, the influence of different initial phase angle of dual rotor and mixing time on dispersive property were studied by preparing specimens of CNTs/epoxy resin composite under continuous stretching machine. Then, the synergistic effect of continuous stretching flow and ultrasound oscillation on dispersive property was studied with various ultrasonic power and synergistic time. In this study, the morphology of blends was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that initial phase angle of dual rotor and mixing time had great effect on the dispersion of CNTs in epoxy resin. The degree of CNTs dispersion was best when the initial phase angle of dual rotor was 0°, and increasing mixing time could improve the degree of CNTs dispersion. Increasing ultrasonic power and synergistic time were helpful to disperse CNTs in epoxy resin. It demonstrated that the synergistic effect of continuous stretching flow and ultrasound oscillation had obviously effect on the dispersion of CNTs.

Effect of magnetic field strength on carbide precipitation behavior in W6Mo5Cr4V3 highspeed steel during medium temperature tempering was investigated. The applied magnetic field promoted the precipitation and refinement of M6C and MC carbides at boundaries and in the grain interior, but maximum spheroidization occurred for those M6C carbides precipitated at boundaries, the stronger the magnetic field strength, the stronger the spheroidization effect. The high magnetic field hinders the precipitation of M2C type carbides, and the M2C type carbides basically disappear when applying the magnetic field.

An apparatus is developed in this paper, which surveys the motion law of the CAM follower. The apparatus is comprised of the frame body, motors, transmission system, execution system, control system and data acquisition system. The displacement curve, speed curve and acceleration curve of CAM are drawn by analyzing the signal from the dial indicators. This apparatus can provide technical data for the mechanical principle course as well as scientific research work.

Effect of remelting processes on the microstructure and mechanical properties of as-cast Nimonic 90 superalloy was investigated by OM (optical micrograph), SEM (scanning electron microscopy), EDS (energy-dispersive X-ray) and tensile tests. The results indicated that the microstructure of the as-cast alloy was mainly composed of γ, γ' and carbides which contain Ti and Cr elements. The average grain size of the alloy tends to increase with mould shell temperature ranging from 350°C to 950°C. The strength of the as-cast alloy decreased with the increasing of mold shell temperature, with constant elongation as the mold shell temperature changes.

Large quantities of VIDP400 vacuum furnace smelting DZ417G oriented superalloys smelting process has been researched, analysis of the main factors affecting the organizational uniformity and stability, as well as the impact of high temperature tensile and lasting properties has been studied. The results showed that: At pulling rate of 4.5~8.5mm•min-1, after 1220°C solid solution treatment and 980°C aging system, the DZ417G superalloy had uniform chemical constitution with oxygen and nitrogen content of the alloy in sharply reduced to 13ppm. It can be got available treatment uniform structure with proper γ'phase size, with high-temperature tensile strength up to 750MPa, elongation of 17% reduction of area 22%. The lasting high temperature performance can reach to more than 100 hours.

Tool wear is easy occurred in titanium alloy milling process which will affect the surface quality. Surface roughness and surface morphology as an important index to describe and evaluate the surface quality has a great influence on service performance. Therefore, the study on the effect of tool wear on surface qualities is important to improve the surface integrity of titanium alloy parts. Cutting radius of ball-end milling cutter is solved to analyze the effect of tool wear on the cutting radius. The tool wear and the surface qualities of TC4 are achieved through wear experiment. And then the influence law of tool wear on surface qualities and chip morphology are analyzed. The results show that surface roughness value decrease firstly and then increases and that chip morphology with flank wear increase from the unit chip to the serrated chip.

A method of fabricating convex plate-shaped micro electrode was proposed based on the electrochemical etching principle. The square sectional electrodes were prepared in advanced using wire-EDM, The micro cylindrical electrode was fabricated firstly by using the eletrochechemical etching method. Then the top end was insulated to protect it from etching. Then the convex plate-shaped micro electrode was obtained in subsequent etching. Comparative experiments in drilling micro-hole in stainless steel with the thickness of 1mm were done by using the cylindrical and convex plate-shaped micro electrode. Results shows that the better locality, smaller side-gap and hole taper could be obtain by using convex plate-shaped micro electrode.

Based on the difficulty to accurately control temperature for torch brazing, the study is concerned with developing low-melting-point solders for brazing pure aluminum. For this purpose, Ge and Zn have been chosen to be added to Al-Si-based alloy. The melting characteristic, wetting property of solders with Al and mechanical property of the brazed joints were investigated. The results show that the addition of 10 wt. % germanium into the traditional Al-12Si (wt. %) filler metal causes its liquidus temperature to decrease by about 23 °C. An addition of 30 % zinc into such Al-Si-Ge ternary alloy will cause its liquidus temperature to drop further to 525 °C. The solders have good wettability with Al. With the increase of Zn content in the alloys, the spreading areas of solders exhibit nonlinear decrease, and there exist a very large value at the zinc content of 15%. When Al-Si-10Ge-30Zn solder was used to braze the pure aluminum, an optimized bonding strength of 116 MPa was achieved.

Through the water compensation models, the article studies the effect of water resources compensation policy on the upstream and downstream areas under differential empowerment systems. Study finds that difference in water resources utilization efficiency is the precondition of water resources compensation policy implementation. With changes of water resources utilization efficiency, the compensation price changes in the same direction and the compensation amount changes in the opposite direction. Finally, water resources compensation policy will improve the welfare of both areas, which is highly consistent with Coase theorem.

A new structure magnetorheological brake with three effective areas was designed, two end surfaces and the cylindrical surface of the rotor work as effective areas, then the effective area was increased with the same volume of the rotor. Depending on the characteristics of the magnetorheological brake structure, the finite element model of the magnetorheological brake was built, the electromagnetic field analysis was performed, then magnetic field quantities of the brake model were got. With the results of the magnetic analysis and the relation between the yield stress and the magnetic field strength of the magnetorheological fluid, the performance simulation of the magnetorheological brake was realized. On these bases, the magnetorheological brake and the mechanical performance test system were developed, the mechanical performance of the brake was researched used the test system, the brake’s properties: torque vs. speed and yield torque vs. current were obtained.

As one of the most important parameters of Direct Current (DC) power supply, Load regulation determines the performance of whole system. In this paper, the internal structure as well as performance parameters of LM2577 boosting converter were deeply investigated and based on this investigation we proposed two new methods of improving its Load Regulation. One method (method 1) is to replace the resistor connected to the feedback pin of LM2577 with a programmable potentiometer and sample the variation of output voltage using an AD converter. The potentiometer is adjusted under the control of feedback algorithm to keep the output voltage stable, thus the load regulation enhanced. In the other method (method 2), the feedback pin of LM2577 is connected to an adder to stabilize the output voltage of DC power supply and increase the load regulation. A voltage divider made up of resistors divides the output voltage and provide the divided voltage to one input of the adder. The other adder input comes from DA converter controlled by microcontroller. To reduce the adjust time and increase the efficiency, PID algorithm is applied in the software part of the system. We use 12-bit AD (ADS1115), 12-bit DA (TLV 5638) and 10-bit programmable potentiometer (AD5293) to test the methods above under the condition of 5V input voltage and 600mA load current. When output is set to 7V, the load regulation is improved from 1.043%, the rate from application circuit in LM2577’s Datasheet, to 0.700% and 0.042% by applying the first and second method, respectively. When output voltage equals 12V, the improvement is from 0.658% to 0.008% and 0.008%. Meanwhile, the method 2 suppresses output voltage ripple to be less than 10mV.

In this paper, environmental friendly phenol formaldehyde modified with larch thanaka and urea was used to make 2-ply bamboo laminated lumber. Effects of two assemble patterns (inner to inner and outer to outer) on physical and mechanical properties of 2-ply bamboo laminated lumber from carbonized and bleached bamboo strips were investigated. The results showed that modulus of elasticity (MOE) and modulus of rupture (MOR) of carbonized bamboo laminated lumber were better than that of bleached bamboo laminate lumber. It illustrated that physical and mechanical properties of carbonized bamboo laminated lumber became better. The MOE and MOR of bamboo laminated lumber, bonding with inner (low density surface) to inner surface, were better than that of outer (high density surface) to outer surface. It meant that MOE and MOR of bamboo laminated lumber were increased by the bonding surface density decreased of bamboo unit. Thickness swelling of carbonized bamboo laminated lumber was lower than that of bleached bamboo, which meant its dimensional stability was better than that of bleached bamboo laminated lumber.

The article describes three usual manners and introduces about one Siemens S7-200PLC’s closed loop control system how to realize the PID , the principle of the PID digital controller, how to use the PID digital controller, an example about how to program with it, and how to convert the input-output variable.

Welding temperature is the main factor that influences welding quality in high frequency induction welding process of composite aluminum alloy thin-walled tube. The finite element analysis software ANSYS is used to simulate temperature field. One complete penetration of thin-walled tube and boundary conditions of thermal calculation are taken into account. Then a linear thermal model is used to load and calculate to draw temperature distribution and thermal cycle curves of welding process. Research results provide corresponding theoretical basis for further analysis of welding stress and strain.

Intelligent sensing system for distribution line condition monitoring is presented. It uses sensing terminals to detect load current, temperature, humidity and water pass state. It uses intelligent sensor to collect the distribution condition information. The information collected by the terminals transmits to intelligent sensing system. It is designed without the need for primary equipment reform, without the need of large-scale construction of communication channel, without the need for power blackout with small investment and big benefit. It greatly improves the power supply capacity, efficiency of the system accident treatment and the reliability of power supply.

With continuous improvement and update of embedded Linux kernel, embedded technology has been widely used in handheld devices and industrial control field. Therefore, a user-friendly graphical user interface (GUI) is essential for these applications. This paper firstly presents the design method for transplanting Qt on embedded platform of ARM9. Secondly it elaborates the device driver development and Qt interface development in Linux system with a Qt test program. All transplantation method of Qt and test program have been tested and verified on the ARM9 platform.

The design scheme for PV system connecting the grid is provided, considering the reactive power compensation, harmonic and lightning effects. Solar power generated connects into the nearby medium and low voltage distribution networks by the inverter. The capacity of solar power total is 1.15MWp. The electricity is generated for personal use; the remaining is connected to the grid system. The scheme is reasonable in design; the system is stable and reliable by the practical testing. It can be used in large range popularization and application.

Corrosion inhibition of N80 steel in 15% HCl was investigated in the absence and presence of different concentrations of some thiosemicarbazide derivatives (Mannich baseI, Mannich baseII) by weight loss, potentiodynamic polarization techniques. The adsorption of Mannich bases obeyed Langmuir adsorption isotherm. Both thermodynamic and activation parameters were calculated and discussed. The absorption process of Mannich base corrosion inhibitors on the surface of N80 steel is spontaneous, endothermic and entropy increase process. Polarization curves indicated that the inhibitor of Mannich bases are the mixed corrosion-controlling one which inhibited anodie corrosion. The results obtained from weight loss, Potentiodynamic polarization are in good agreement.

In order to improve the accuracy of diagnosis pumping, and accelerate the speed of diagnosis, a fault diagnosis model based on improved extreme learning machine (RWELM) was proposed. Firstly, it extracted the energy characteristic eigenvector of dynamometer cards of an oilfield in northern Shanxi by using wavelet packet decomposition method. Then through simulation of fault diagnosis, and compare with the extreme learning machine (ELM), RBF neural networks and support vector machine (SVM). The experimental results show that the accuracy and the speed of fault diagnosis based on the RWELM are better than the ELM, RBF neural network and SVM.