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The utilization of the stone material in Chinese official buildings in early Ming Dynasty was mature, and the characteristics performed at the tremendous volume in scale, the flowing lines and the plain style in decoration. This paper took the stone material used in the official buildings in the three capitals (Fengyang, Nanjing and Beijing) as the research object, analyzing the stone’s characteristics, categories and related the transport ability in early Ming Dynasty.

Aiming at the problem that the tracking frequency range of ultrasonic power is fixed, and the accuracy of tacking frequency is low, the tactics of digital phase-locked loop frequency tracking technology combined with changing step searching circuit peak is proposed. The frequency tracking is achieved by combining the advantages of digital phase-locked loop frequency tracking technology with changing step searching circuit peak, building the digital phase detector circuit and current effective value converter circuit, taking the feedback of sampling the phase and circuit peak as basic of frequency tracking. Build the simulating model in Multisim. The experiment results show that composite frequency tracking strategy can effectively achieve frequency tracking and dynamically lock transducer multi-modal resonance.

The ingot of Sm-Fe alloy was prepared by vacuum melting. After a process of coarse crushing, it was made into Sm-Fe ribbons by melt-spinning. By analysis of XRD and SEM, it was confirmed that the ribbons composed of fine Sm2Fe17columnar grains with almost the same orientation can be obtained under the condition of 5~7m/s surface rotating velocity of Cu wheel, suitable nozzle size, injection pressure, temperature and composition of the Sm-Fe melt to regulate cooling rate and crystallization. The achievement of the ribbons lays a foundation for preparing anisotropic Sm2Fe17Nxmagnetic powders by rapid quenching.

This paper presents a new modeling method, based on the physical structure of the IGBT module, considering the distribution parameters of high frequency.This method is simple and the wideband model has physical meaning, by choosing suitable model initial parameters as well as the objective function which use the iterative optimization algorithm to solve the model parameters.Comparing the wideband model with the measured results ,the wideband model maintain high accuracy in the range of 100KHz ~ 20MHz.

The density distribution characteristics of non-equilibrium carrier from spontaneous emission ahead of the tip of the current filaments in high gain semi-insulating GaAs photoconductive semiconductor switches are analyzed. The results show that the ratio of volume to area of the current filament and the average carrier density in the current filaments are two key factors that affect the photoionization effects of the current filaments. The reabsorption of wavelengths λ ≤ 876 nm radiations plays a dominant role in producing the maximum carrier density. The maximum density of photo-generated carrier is approximately 1~3 orders of magnitude lower than the average density of excess carrier inside the current filaments.

Based on a large number of actual production data, the paper researches the hydraulic characteristics of high water cut crude oil pipeline in Sabei Oilfield and summarizes change rules of Hydraulic friction coefficient and Reynolds number of high water cut crude oil pipeline under different flow states. After making correction model of Hydraulic friction coefficient at different flow states and using the optimization technique to determine the coefficient in the model, based on C++ builder programming platform developed the software of pipeline hydraulic friction coefficient of correction. The results calculated from the software show that the correction model can significantly reduce the pipeline hydraulic calculation errors which are declined from more than 20% to less than 5%.

Through a practical project - the remediation of the landscape and the environment in Jingmai Village ,which analyzes the problem of the application of old and new material in the remediation and design of traditional village. Under the social background of tourism promoting economy, transform the incongruous elements in traditional villages and intend to restore the landscape and the environment of traditional Dai national folk houses, so as to achieve the dual purposes of protection and development.

This article overviews the general condition of roads and cement concrete in Hengshui City; Summarizes the characteristics of cement concrete pavement; Analyses the causes of current route status. Take the cement concrete pavement of Hengde Highway Jingzhou Connecting Line as an example, the article introduces the cement concrete pavement construction technology, construction quality control measures and effects, and the changes of construction quality two years after opening to traffic.

Based on empirical microwave data on the second Ring Road in Beijing, spatial and temporal characteristics of traffic congestion were analyzed. Three specific indexs for the congestion have been analyzed, i.e., congestion duration, time percentage of traffic congestion and key congestion sections. The hazard-based traffic congestion duration model was established through survival method. Temporal-spatial distribution of traffic congestion was studied using non-parametric method. The discrepancies of traffic congestion on different time and different links were considered. Results show that there has a big difference on congestion duration and congestion number between different links. Hazard rate will be less than 10% when congestion lasting more than 20 minutes. Three characteristics of the key congested points are confirmed. The judgment for key congestion sections show that key congestion segments have original affect to other sections.

China's commercial magazine faces of increasingly fierce competition in the customer, so it must improve its management and marketing method to enhance competitiveness. It is the key point to strengthening customer relationship management. The study in this paper uses data mining techniques to enhance the management of the customer to explore new customers, maintain overall customers and accelerate the development of the magazine. Through the establishment of large database and data mining, we find useful data and the relevance to support decision-making and better improve the competitiveness of the magazine.

Current transformer (CT) is an important transmission equipment in power systems. DC bias and remnant flux can change the working point of CT in the core magnetization curve and has a direct impact on the accuracy of electric energy metering and measurement. The simulation circuit model is built by using the simulation software PSCAD and the change of ratio error, phase displacement and exciting current with DC bias and remnant flux are analyzed. The results show that DC bias and remnant flux will both increase the ratio error and phase displacement in opposite directions and the error size will be far more than the limit value when DC bias and remnant flux exist in same direction at the same time. Furthermore, the existence of DC bias and remnant flux will also cause the raise of exciting current size, asymmetry of exciting current waveform and appearance of even harmonics. This will seriously affect the transmission accuracy of measuring CT.

Passive housing is a combination of technological products which base on building energy saving concept, and it makes full use of solar energy, geothermal energy and other renewable energy to reduce the consumption of primary energy used in heating to 15 kw/h·m2·y, however, the energy consumption in low-energy house, which has equipped with various kinds of energy saving technologies, is about 30-75 kw/h·m2·y, thus, passive house has a better performance in energy saving than low-energy house. Energy saving technologies suitable for passive house and low-energy house in hot summer and cold winter area are proposed in this paper through introducing the contribution Germany has made and development of technology in passive housing, using its advanced technologies and practical experience ins passive house as reference and taking Chinese unique climate condition, building types and residents living habits into account.

In order to ensure the reliability of the operational of circuit breaker, we used intelligent monitoring unit to realize the high-speed acquisition of the electrical, mechanical and insulated signal in the operation of the high voltage circuit breaker and actuator. Combined with signal processing and fault analysis theory, we estimate the operating status based on the accurate acquisition of the various operating parameters in breaker actuator. We also developed a system of remote online monitoring of circuit breaker status and fault diagnosis. The system ensures reliable operation of the circuit breaker. It also provides fast and accurate information for operation scheduling and maintenance personnel and accumulates large amounts of raw data for the state overhaul of the circuit breaker.

In order to study the effect of several factors on the shrinkage performance of lime-fly ash stabilized crushed stone, temperature shrinkage coefficients and dry shrinkage coefficients of mixtures with different gradations, lime and fly content and age were measured. Results indicate that mixture with a stone-on-stone contact has better shrinkage-resistance performance; For the same gradation, both dry shrinkage coefficient and temperature coefficient become improved with lime-fly content increasing; when the lime-fly content is the same, temperature shrinkage coefficient increases with longer age; Results of analysis of variance show that to the temperature shrinkage coefficient, the effect of age and lime and fly content are important, and the latter is greater. To the dry shrinkage coefficient, gradation and lime and fly content are important factors, and the former is greater.

The transfer characteristics of current transformers (CT) change due to DC bias, which directly impacts the accuracy of measurement and power metering. Based on equivalent circuit models and core magnetizing characteristic, qualitatively analysis current transformer saturation increase errors of CT. Transfer errors under DC bias and remnant flux are also obtained based on J-A model of CT in PSCAD/EMTDC and full-wave Fourier algorithm to show that the ratio error and phase displacement increase with the DC bias. Based on FFT spectrum analysis to identify remnant flux and DC bias provides scientific basis for error compensation of CT.

Chitosan has unique properties among biopolymers, especially due to the presence of several reactive groups, such as OH and NH2, which can react with many compounds. Chitosan and its derivatives are able to chelate metal ions, eliminate free radicals and resist oxidation. The development of chitosan and its derivatives used as metal ions chelating agent and free radical scavenger was overviewed. In addition, the application of chitosan and its derivatives and their potentiality in paper industry was prospected.

The aim of this investigation was to evaluate solid digestate as a growing substrate for plug seedlings. Four mediums prepared from solid digestate, vermiculite, perlite and activated carbon were used to determine optimum growing substrate for tomato seedlings (Zhongshu six). The substrate used in this study mixed as solid digestate: vermiculite: perlite: activated carbon were (m:m): 4:13:2:1, 8:9:2:1, 12:5:2:1 and 16:1:2:1, respectively. Besides, peat: vermiculite of 2:1 (v:v) was used as the control. Various seedling indices were measured to assess the quality of the substrates. Tomato seedlings grown in solid digestate: vermiculite: perlite: activated carbon of 16:1:2:1 (m:m) displayed the best quality compared with all the other treatments, due to a correct balance between the digestate nutrient supply and the physical properties provided by vermiculite, perlite and activated carbon. Solid digestate could be a potential alternative for plug seedlings.

The possible exploitation of two-phase anaerobic digestion for swine manure was investigated in this study. One-phase and two-phase anaerobic digestion process were investigated in continuous stirred-tank reactor with hydraulic retention times 15 days (hydrolysis and acidification for 3 days and methanogenic12 days in two-phase). When the organic loading rates were equal to or less than 4 g VS/L day, the biogas yield and volumetric production of two processes were no significant difference. However, in the case of organic loading rates being equal to or higher than 5.0 g VS/L day, two-phase biogas yield and volumetric biogas production averaged 0.294 L CH4/g VS added and 2.218 L/L day, compared with one-phase averaged 0.255L CH4/g VS added and 2.168 L/L day, respectively. Significant advantages in saving cost of biogas project were indicated by the comparison of biogas production and COD degradation in the one-phase and two-phase processes.

According to the multivariable coupling、 large time delay, non-linearity and time-varying and other difficulties of circulating fluidized bed boiler combustion system, a kind of control technology based on neural network to circulating fluidized bed boiler combustion system was presented. Actual parameter data of a paper mill in Kunming and neural network control principle were used in the establishment of a circulating fluidized bed boiler combustion system mathematical model and modified BP neural network algorithm training. Results of MATLAB simulation show that boiler combustion system control precision was effectively improved and good effects in production and application were got.

A novel copolymer based on bromobenzene and 3,4-ethylenedioxythiophene (EDOT) was electrochemically prepared in boron trifluoride diethyl etherate (BFEE) via direct anodic oxidation of the monomer mixtures on indium-tin oxide working electrodes. The corresponding polymer was characterized by cyclic voltammetry and UV-vis spectroscopy. The copolymer had a very well-defined and reversible redox process. The band gap of the copolymer was calculated as 1.42 eV, respectively from the onset of π-π* transition of conjugated backbone. Furthermore, the copolymer exhibited multicolor electrochromism, high redox stability and reasonable response time.

The objective of the study is separating the gold (I) and its coexistence base metals from cyanide leaching solution by homemade weak and strong alkaline anion exchange fiber inseries, by using their selectivity and the adsorption capacity, respectively. The optimal conditions of the adsorption/elution are as follows: for WAAEF, the suitable flow rate of the adsorption is 61.4 BV/h, and the loading density is 0.262 g/cm3; for SAAEF, the suitable flow rate of the adsorption is 872.2 BV/h, and the loading density is 0.202 g/cm3. A mixture of 2.5 mol/L NH4SCN with 0.1 mol/L NaOH is chosen as the gold (I) eluent, and the eluention flow rate is 96.9 BV/h. The conclusion is that the homemade fibers could be used inseries to extract the gold (I) from cyanide leaching solution.

The adsorption of trichloroethylene (TCE) and Cd2+ combined contamination in the groundwater by attapulgite were studied, and the effects of pH, dosage of attapulgite and adsorption time on adsorption were investigated, equilibrium of the adsorptions processes were further conducted. Results showed that the adsorption rate of TCE affected little by the pH; TCE adsorption equilibrium reached after 3d, the removal rate was 71.34%; when attapulgite dosage was 0.03g, the adsorption rate was up to more than 51.08%. Freundlich isotherm was best fitted the adsorption process of TCE. Compound contamination of TCE and Cd2+ decreased the removal rate of TCE; but was in line with Freundlich adsorption isotherm.

To recycle waste heat from circulating water, the model of the power plant heat pump regenerative thermal system is put forward, and the indexes of the system are analyzed. It is indicated in the specific case that the absorption heat pump has an advantage over the compression heat pump. Using the extraction steam of the low pressure cylinder as its driving heat source, economize on coal can be realized in the condition that the coefficient of performance(COP) of the heat pump is above the critical COP. For the case of the compression heat pump, the fuel efficiency is improved a little, but on the other hand, as the station service power is increased, the power supply coal consumption is increased too.

We sampled total of 74 polluted soil samples in the polluted field by means of setting 37 plane sample points and digged sampling caves according to the original producing layout and pollution situation of Suzhou chemical plant. The total quantity and the concentration of active form of heavy metal elements in the soil samples were analyzed by atomic absorption spectra; and the volatility organics in the soil are measured using jointed gas chromatography-mass spectrograph measurement. The results show that the polluted area is over 30%. The main pollutants are carbon tetrachloride, methylene chloride, aromatic compounds in the north part of the field, and toluene, P-dichlorobenzene, and petroleum hydrocarbons in the south part. The main pollutants underground 2-3 m are petroleum-derived hydrocarbons, volatile halogenated hydrocarbons, and aromatic compounds.

Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) is the most important and widely used technology which is mainly used to analyze the protein molecular weight. Fibrin zymography based on the SDS-PAGE is the best method for qualitative analysis of unknown plasminogen activators (PAs), especially for the analysis of molecular weight. In electrophoresis technique, molecular weight marker is the most important factor. However, it is difficult to detect protein molecular weight markers in fibrin zymography. In this study, some important factors, such as concentrations of fibrinogen and plasminogen, are discussed. Our results provide an efficient and convenient method which can clearly exhibit the dark blue bands of protein molecular weight (MW) markers and the transparent bands of PAs against the light blue background on one gel at the same time, and show high sensitivity.

Feathers, as a waste, are produced in large quantities from poultry processing industry every year. In this paper, feathers were biodegraded by Stenotrophomonas maltophilia DHHJ which was isolated from soil samples. The results show that the optimal conditions for the feather degradation and the keratinase production are 2.5% feather as substrate, the initial pH of 7.8 and cultivation at 40 °C for 5 days. Salts, KCl and NaCl, can increase feather degradation slightly. The proper concentration of Tween 80 can enhance keratinase production significantly. EDTA, as a metalloprotease inhibitor, greatly inhibits keratinolytic activity.

In ouder to prepare the waterborne UV-curable polyurethane acrylate coatings, the anionic polyurethane acrylate emulsifier and bisphenol-S eopxy acrylate were synthesized. The curing process, kinetics and properties of waterborone UV-curable epoxy acrylate/polyurethanes acrylate coating were investigated by FTIR, DSC and DMA. The results show that the static initial curing temperature Ti is 52.36 oC, peak temperature Tp is 71.58 oC, the finished temperature Tf is 89.15 oC. The curing reaction can be described by two-parameter autocatalytic Šesták-Berggren (S-B) model.This coating has a better UV-curing property. The dynamic mechanical analysis showed that the glass transition temperature Tg of coating film is 52.70 oC.

Office Automation (OA) means office and management automated. OA is a comprehensive technique. It contains the computer technology, communication technique, the system science, behavior science, and so on. It can deal with massive, indefinite tasks which traditional data processing technology may do difficultly. By each enterprises and institutions, all branches of government have different business and functions, so the market demands of OAS are also differences. The general structure of the OA and the system has been designed by analyzing the workflow model in COAS. It enables dynamic tracking business process.

In order to prepare the innocuity polyvinyl chloride (PVC) products, the calcium/zinc stearate was used as the thermal stabilizer of PVC and the polyols were used as co-stabilizer of Ca/Zn stabilizer. The influence of polyols on the stabilization efficiency of Ca/Zn stabilizer to PVC was investigated by Congo red methods. The rheological behaviors and dynamic mechanical properties of PVC were also investigated by rotational rheometer and dynamic mechanical analyzer (DMA). The results showed that different polyols have different influences on the stability, but the pentaerythritol has a good synergy effect with Ca/Zn stabilizer for PVC and pentaerythritol and dipentaerythritol have a lower melt viscosity and good product color.

In order to prepare the innocuity polyvinyl chloride (PVC) products, the calcium/zinc stearate was used as the thermal stabilizer of PVC and the polyols were used as co-stabilizer of Ca/Zn stabilizer. The influence of polyols on the stabilization efficiency of Ca/Zn stabilizer to PVC was investigated by Congo red methods. The rheological behaviors and dynamic mechanical properties of PVC were also investigated by rotational rheometer and dynamic mechanical analyzer (DMA). The results showed that different polyols have different influences on the stability, but the pentaerythritol has a good synergy effect with Ca/Zn stabilizer for PVC and pentaerythritol and dipentaerythritol have a lower melt viscosity and good product color.

A sensitive electrochemical sensor for the detection of parathion based on molecularly imprinted polymer of organic-inorganic hybrid sol-gel from PTMOS and chitosan onto glass electrode was constructed. The sensor exhibited good selectivity and sensitivity to parahtion．The procedure of forming recognition cavity and sensitivity to parathion on the imprinted electrode were demonstrated. A highly linear response to parathion in the concentration range of 3×10-7～1×10-4 mol/L was observed, with a detection limit of 1×10-7 mol/L (S/N=3). ParathSuperscript textion imprinted and nonimprinted polymer films were exposed to a series of closely related compounds and the sensor exhibited good selectivity and sensitivity to parathion.

Since the adverse factors such as deficient penetration and long reaction time have restricted the complete microwave-used drying of municipal sludge, the microwave-induced drying was considered which has advantages in such aspects. The investigation of the microwave-induced drying to uncover the mechanism has great meaning for its development and usage. The experiments indicated that temperature was the decisive factor affecting the drying rate. The microwave-induced sludge reached the highest drying rate at the moisture rate of 40%, with a 20% grade promotion compared with that of the original one. The molecular fracture caused by microwave radiation had obviously accelerated the drying process and the drying rate was rising in proportion to the microwave radiation dose. The diffusion coefficient of microwave-induced sludge was obviously enlarged more than 2 times grade. In this research, model Weibull proved to fit the experiment of thin-layer drying for municipal sludge best compared with the other ones.

Combined with practical operation of a biomass direct-fired power pant in South China, the whole life cycle of the process, including biomass growing, transportation, pretreatment, combustion power generation and power plant manufacturing are analyzed by means of LCA. The energy consumption and the impact on environment in each stage are also collected and calculated. The results show that 2182.32 MJ fossil energy is consumed to generate 104 kWh power. The total loading of the impact on environment is 13.45 PET2000and the mainly impact on environment is soot and ashes. Compared with coal-fired power, biomass direct-fired power plant can reduce 5282.87 kg CO2emissions during the process of generating 104 kWh power, which plays a positive part in mitigating greenhouse gases.

The four main effect production factors, doping rate, calcination temperature, soaking time and heating rate, are chose to design experiments based on the orthogonal table L9(34) to prepare urea-modified titanium ore (UTO) sorbents. And the decoloration efficiency of methyl orange is examined by using UTO as sorbents under dark-state absorption. Based on the orthogonal experiments, we obtained the optimal operating parameters: urea 8.0wt%, soaking time 3h, calcination temperature 300°C and heating rate 10°C/min. As the preparation condition was run at the optimal conditions, the decoloration efficiency of methyl orange reached 98.1%, which was significantly better than the undoped samples. Thus, it is feasible to treat dye wastewater by these UTO sorbents.

Using calcined sulfate-modified titanium-bearing blast furnace slag (STBBFS) as photocatalyst, decolorization efficiency of methyl orange (MO) in the presence of Cr(VI) were studied. The effect of solution pH on the decolorization efficiency of MO and reduction efficiency of Cr(VI) have been investigated. The results indicate that the acidic solutions are favorable for the photocatalytic oxidation of MO in the presence of Cr(VI), and the optimum pH for oxidation of MO is 1.5. The increasing of photocatalytic activities in the compound system can be attributed to five main reasons: (1) the redox reaction between Cr(VI) and MO; (2) adsorption of Cr(VI) species and dye molecule onto STBBFS surface; (3) the visible light irradiation; (4) Cr(VI) species reduced to Cr(III) by Mn2+ in STBBFS photocatalyst; (5) Moreover, the addition of Cr(VI) species able to act as electron scavengers to catalyst surface promotes the effective separation of electron-hole, and hence promote the increase of decolorization efficiency of MO and reduction efficiency of Cr(VI) in Cr(VI)-MO system under visible irradiation. UV-vis spectral analysis indicated that MO was completely mineralized in the presence of Cr(VI) after 240 min. FTIR spectral analysis showed that all these characteristic peaks of Cr(VI) and MO disappear after photoreaction, indicating the degradation of Cr(VI) and MO.

Pure magnesium hydroxide (Mg(OH)2) nanoparticles were synthesized successfully from dolomite-talc ore via chemical precipitation. Carbonate minerals in dolomite-talc ore were dissolved with hydrochloric acid, and Fe2+ was oxidized to Fe3+, then Fe3+ and Al3+ were removed by adding ammonia to adjust pH to reach 6. Magnesium hydroxide (Mg(OH)2) nanoparticles with about 20nm thickness and lamella shape were obtained successfully when pH>10 in the presence of a nonionic surfactant polyethyleneglycol (PEG) with 3wt %, which reached by adding more ammonia. The XRD results show that the amorphous precipitate with 87% Fe2O3 generates at pH=6. However, CaMg2Cl6 (H2O)12 generates when pH = 7, then disappears with the increasing of pH. Mg(OH)2 appears at pH= 9 and pure Mg(OH)2 particle is obtained at pH > 10. Meanwhile, PEG plays an important role in the growth of Mg(OH)2 nanoparticles.

In view of the traditional color of historic buildings in old Nantong city is gradually lost and the buildings lack of color planning in the process of large-scale expansion of the city, the color characteristics of Nantong historic buildings are analyzed from the perspectives of the geographical tradition and characteristic time. Meanwhile, the color design method of Nantong historic buildings in architectural renewal are proposed.

In this paper the influence of mineral admixtures on early shrinkage of ordinary concrete with the same water-binder ratio is studied by self-made equipment and CABR-NES deformation instrument developed by China Academy of Building Research Institute. All concrete specimens are cured with one surface exposed to air and others are covered with plastic film. The replacement ratio of mineral admixtures is 10%, 20% and 30%, respectively, and a mixture of a combination of both fly ash and slag is also studied. The results indicate fly ash reducing the early shrinkage of ordinary concrete, and the shrinkage decreases with the increasing of replacement ratio, but the effect is not so significant when the replacement ratio is above 20%. Slag also reduces the early shrinkage of ordinary concrete, and the shrinkage decreases with the increasing of replacement ratio, but the effect is not so significant when the replacement ratio is below 20%. Mixture with a combination of both fly ash and slag has lower shrinkage than mixture with fly ash.

In the existing technology of cold asphalt pavement recycling, it is only the aggregate that is used again after the crushing and screening of the Reclaimed Asphalt Pavement (RAP), but the asphalt is discarded. So a lot of asphalt resource is wasted. The technology of emulsification and recycling of RAP in room temperature reuses the aged asphalt in the RAP thereby effectively reducing the quantity of newly added asphalt and also improving the performance of the mixture. The application of this technology will save a lot of valuable resources, reduce material costs and save project investments. The technology also contributes to the practice of “resource-saving and environmental-friendliness” in road construction.

A simplified mechanical model in view of concrete component stability problem on fire was established. Assuming the temperature of fire and load as control variables, and material strain (or intensity) as state variables, destabilization mechanism of concrete component under high temperatures was carried out with the application of cusp catastrophic model. And the nonlinear mutation characteristics and failure mechanism of concrete component on fire were investigated. The results indicate that system's catastrophe characteristic is determined by fire duration, temperature, load capacity and load characteristics. When K=-F'(u)/km>1, component destructs in the form of ductility failure, and when K

In this paper, three-dimensional numerical simulation is conducted on the flow and heat transfer process for elliptical tube heat exchanger with rectangular vortex generators and triangular vortex generator by Fluent software, respectively, and the performance for elliptical tube heat exchanger with plate fin is compared. The results show that the Nusselt number increases with the increase in Reynolds number for the inlet velocity range from 1 to 5m/s, friction coefficient decreases with the increase in Reynolds number; at the same Reynolds number, Nusselt number for fin with Vortex Generators and friction coefficient are higher than that of elliptical tube with plate fin ; the vortex generator shape and angle of attack have a great impact on the comprehensive performance within a simulated attack angle and the velocity, at the same pump power, the comprehensive performance for heat exchanger with the rectangular vortex generator increase up to 10%.

The influence of ultrasonic oscillation process on the performance of oxidized graphene (OG) /epoxy resin (EP) composite is studied. The results show that the oscillation process can greatly improve the tensile strength, shear strength and hardness of EP, as well as it’s morphology, for the compatibility of EP with OG is greatly improved after oscillation. OG can improve the dielectric constants of EP to some extent, while increase the tensile strength at low content, decrease with adding more OG. The tensile strength of EP is 19.32MPa and the dielectric constants 1.73 with 3/1000 content of OG. The morphology of the EP shows that the fracture surface of the composite is layer shape while the surface of EP is smooth, indicating OG change the structure of EP after cross-linking reaction.

By introducing ultrasonic field during the solidification process of aluminum alloy melt, the effects of ultrasonic treatment (UST) on macroscopic and microscopic segregation were investigated. The results show that under 170W of UST, the macrosegregation degree of Zn is diminished to the minimum, the segregation index reaches 0.0583. At a higher ultrasonic intensity, the UST greatly contributes to the positive centerline segregation in the ingot. Compared with conventional casting (without UST), the solid solubility of Zn, Cu and Mg inside crystals of ultrasonic casting can be strengthened so that the microsegregation tends to be minimized. Overall, the ultrasonic cavitation and acoustic stream promote the redistribution of solute elements in the ingots, and a reasonable ultrasonic power is beneficial to weaken the segregation.

In order to improve the dynamical respond of the weighing system and to meet the demand of rapid weighing, a new method based on radial basis function neural network (RBFNN) is introduced in this paper. The dynamic system is described as a network and the output values of steady state are predicted by an on-line modeling before the platform has settled to the steady state. The sample weight is calculated according to weighted moving average. The experimental results proved that the neural network method in this paper can be used to effectively reduce the weighing time and to increase the accuracy simultaneously.

In this work, some combustion experiments on PVC, rice hull, and their mixture were carried out in a fixed-bed reactor to obtain the influence of temperature, oxygen concentrations on the emission of NO. The NO emission during the co-combustion of PVC and rice hull had the same tendency as the rice hull combustion had, and it increased slowly along with the rising of temperature and oxygen concentration. The experiment results also indicate the co-combustion leaded to lower NO concentration, and it was considered that some reducing substances existed in co-combustion process leaded to a certain reduction in NO emission. The FactSage and Chemkin simulation results have a good agreement with the experiment data, and reveal that the main production reactions are: NO2+ONO+O2, NO2+HNO+OH. In addition, large amounts of volatile released by PVC in co-combustion process formed strong reducing atmospheres, which acted the major roles in the NO reduction.

We optimized the gallium nitride(GaN)photocathode’s structure in three aspects for higher quantum efficiency. AlN is used to replace GaN as the buffer layer, which can act as potential barrier to reflect electrons back to surface. The optimal thickness of emission layer is calculated as 162.5nm, and considering the graded doping profile, we optimized the thickness as 180nm. Three built-in electric fields are introduced by Mg graded doping, and the intensities of the high fields are calculated to give the quantitive results of their influence on quantum efficiency. After surface cleaning and activation, quantum efficiency of the optimized sample was greatly increased and the highest value of 56% was achieved at 5.20eV. More quantum efficiency enchancement is possible by further optimizing the photocathode structure.

Obtaining a uniform thickness of the final product using thermoforming is difficult, and the thickness distribution depends strongly on the distribution of the sheet temperature. In this paper, the time-dependent temperature distribution of the total sheets in the storing process was studied because the temperature after the storing process is the initial temperature of the preheating process. An analysis code for simulating the storing process was developed under the condition that the thermal conductivity caused by contact resistance between sheets was assumed as a large value. In this study, the number of sheets in the storing room was adjusted for finding out the effect of it. The analysis results show that maximum temperature difference between sheets was significantly different when adjusting the number of sheets in the storing room. The temperature distribution of the total sheets and the method for analysis in this study will be used to optimize the storing process for higher quality of final products.

Thermoforming is one of the most versatile and economical processes available for shaping polymer products. To improve the quality of final products, the temperature difference between surface and center of sheet should be continuously minimized. But, the temperature difference between surface and center of sheet can not be freely reduced because of low thermal conductivity of sheet materials. In this paper, an analysis model was developed under the condition that the inputted heat flux was expressed by an exponential function form. In the following step, an optimal design was carried out using a 3rd order polynomial. The optimal results show that the developed method can be used to reduce the temperature difference between surface and center of sheet by adjusting the parameter of time-dependent heat flux.

The hydration heat of aluminate cement containing magnesium aluminate spinel (MA-spinel) and Commercial Lafarge cement are studied. The results show that five stages exist in the hydration processes of both cements, e.g. pre-induction, induction, acceleration, deceleration and stabilization stage. TheNvalues of the two cements are both lower than 1 in acceleration stage, on the contary higher than 1 in stabilization stage. As a result, the hydration is mainly controlled by nucleation reaction and diffusion process in acceleration stage and stabilization stage respectively. The hydration heat of aluminate cement containing MA-spinel is lower than Lafarge cement. Accordingly, the hydration rate of aluminate cement containing MA-spinel is slower than that of Lafarge cement.

Al-matrix self-lubricating which added MoS2 as solid lubricant was prepared by casting under variation in content of Si、Fe、Mn、MoS2、Cr3C2. Friction and wear behavior were investigated on MPX-2000 friction and abrasion machine. The microscopic structure and phases were analyzed by metallographic microscopic and XRD. The results show that the main factor influencing friction coefficient is Si, it can reduce the wear rate. Addition of MoS2 can reduce friction coefficient, Fe is used to improve the mechanical properties. Cr3C2 enhances the wear resistance.