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Influences of polypropylene (PP) fiber and hydroxyethyl methyl cellulose (M) on the shrinkage rate of cement mortar and its potential mechanism were investigated. Results show that both the addition of trilobal PP fiber and M would reduce the shrinkage rate of cement mortar if well applied. With the increasing of PP content, the shrinkage rate firstly decreases and then increases, and reaches the lowest shrinkage degree with fiber content of 0.20% (volume fraction). While for cement mortar with M, the greater the dosage, the less drying shrinkage rate. An addition of 0.6% M contributes to a decrease of 23.8% for the 180-days drying shrinkage than the control. Additionally, a combination of both PP fibers and M can significantly reduce the drying shrinkage of mortar, resulting in a decrease of 40% for the shrinkage rate.

To study the process conditions for preparing sultamicillin tosilate β-cyclodextrin inclusion.Method: Choose the usage ration of sultamicillin tosilate with β-cyclodextrin, the inclusion temperature and the time of reaction as the main factors, and use the inclusion yield as evaluated indicators and the process condition to conduct the L9 (34) orthogonal experiment Optimization Pack sultamicillin tosilate.Outcome: The optimum inclusion process condition: molar ratio of the sultamicillin tosilate with β-cyclodextrin is 1:8, inclusion temperature is 47°C, inclusion time is 40 minutes.Conclusion: The process condition of using β-cyclodextrin inclusion to inconcluse sultamicillin tosilate is feasible, effective, and of applicative value.

Sodium chloride (NaCl) is often used for warm mist elimination because of its easy deliquescence performance. In this paper, how dosages of NaCl with two sizes affect warm fog was investigated. The changes of light transmittance (T) and fog drops inside the fog chamber were monitored. Results indicate that NaCl particles smaller than 40μm work better than that of 40-100μm, shortening time of the light transmittance recovering to 60%(t60%) by 83.3% with 25g. Reasons for this are they can decrease the percentages of small droplets, increase that of large droplets and the average sizes of fog drops, which are results from the condensation growth and coalescence growth.

In order to solve the problems of uneven mixing and aerating in municipal solid waste composting, we present a structural design of mechanical agitation biological reactor. The biological reactor system is composed of cylinder tank, agitator, motivation and drive device. The agitator shaft of reactor is hollow and has 24 holes under agitator blade. The article not only introduces the structural design and check of main body, and rack of reactor, but also the selection of type of arranger. The design of agitator gives consideration to both agitation and aeration, which makes air and materials mixed sufficiently during agitation and the fermentation is more fully.

Emissions of air pollutants from coal-fired power plants pose a threat to healthy living environment. Developing renewable energy and changing electricity generation structure dominated by coal-fired power has become a vital national strategy. In this paper, taking a rapidly urbanizing coastal area in southern Laizhou Bay of China as the study area, a scenario planning concerning substitution of wind power for coal-fired power in enterprise-owned power plants was conducted. Coupled with the electricity generation prediction by a grey prediction model GM (1, 1) and the calculation of pollutant emission intensity, we obtained three scenario schemes: no substitution (Scenario 1), low substitution (Scenario 2) and high substitution (Scenario 3). The results showed that Scenario 1 is not acceptable; Scenario2 is acceptable, but not ideal; Scenario 3 is optimal. The electricity generation structure under Scenario 3 has been radically converted from the type dominated by fossil fuel to one dominated by renewable energy, becoming an environment-friendly power generation framework with fairly low pollutant emission densities. This study can contribute to local managers to seek more concrete measures in mitigating the conflict between electricity demand and environmental health.

Effect of the solid-solution treatment on the casting structures and properties of the die-casting Mg alloy was explored through the way of adding mixed rare earths Y, Gd and Nd into the commercial Re-AZ91 Mg alloy . The results show that the solid-solution treatment could improve effectively the microstructures of the alloy, and Mg17Al12 phrase on the grain boundaries could transform from network struture into dotlike or granular one. At the same time, the compounds on the grain boundaries were less than those before the solid-solution treatment, the compounds were dispersed inside the grain . Both the microstructures and the mechanics properties of the alloy could be improved remarkably, and also, the tensile strength σb could reach over 280MPa, the elongation ratio δ over 9% when the temperature of the solid-solution treatment was between 270°C and 410°C. When the temperature of the solid-solution treatment exceeded 420°C, coarse Al-RE compounds would be formed inside the alloy, which could reduce the mechanics properties of AZ91 Mg Alloy.

The calculation of the projectilepenetration into target has always been a hot and difficult issue in thescholastic circles. In recent years, a new numerical method, XFEM, has been emerged basedon the conventional finite element method (CFEM), so that the crack propagationproblem has been developed by leaps and bounds. Based on XFEM, the researchfocuses on the crack propagation problem in the process of projectilepenetration into target. In addition, the crack propagation mechanism and itsinfluence of material mechanical properties in the process of projectilepenetration into target are analyzed.

Using methods of spatial autocorrelation analysis and trend analysis, the paper studies the spatial distribution pattern of NDVI based on the GIMMS NDVI dataset (1998-2008), in Western Jilin. The maximum value for 15d is got through the method of MAX processing. Results show that: the NDVI in growing season shows a rising trend in western Jilin in 1998-2008. In the study area, the NDVI in Western Jilin shows positive spatial autocorrelation in the whole region, but the partial NDVI is apt to scattered distribution, which means the vegetation cover of Western Jilin is generally fragmental.

In this paper we take advantage of the phosphate film which has a porous structure, by phosphate process on the surface of nickel plated copper conductor so as to improve the bonding force of wire and ceramic layer; Through the study of resistance voltage breakdown after phosphate , phosphate liquid was determined Manganese dihydrogen phosphate for 3g100-1ml, Zinc Nitrate was 8g100-1ml, Sodium Fluoride was 0.45g100-1ml; Optimum temperature was 60°C and the appropriate time was 15min at the temperature of 60°C.

Plate-like Sr3Ti2O7powders with anisotropy were prepared by KCl molten salt synthesis (MSS) method, the effect of different SrCO3/TiO2ratio and calcination condition on the phase transition, particle size and morphology of powders were investigated. The results show that SrTiO3phase coexist with Sr3Ti2O7phase and SrTiO3is the main phase as the SrCO3/TiO2ratio is 1.15~1.25:1. Pure Sr3Ti2O7phase can be obtained as the SrCO3/TiO2ratio is 1.55~1.65:1. The aspect ratio of plate-like particles increases firstly and then decreases as the SrCO3/TiO2ratio increases. The sealed and unsealed condition has no influence on the phase structure of the powders. But the aspect ratio of unsealed particles is smaller than that of sealed particle. Finally, the formation mechanism for Sr3Ti2O7particles was discussed.

Sodium polyacrylate as a kind of high absorbent resin, has an excellent water absorption performance, is low in price and isn’t corrosive. Compounds of different particle sizes and components were prepared using sodium polyacrylate and sodium chloride. They were used in the fog chamber to disperse warm fog respectively then. Experiments were carried out to investigate how particle size and composition affect the warm fog dissipation. Results as follows are obtained: the time light transmittance recovers to 60% (t60%) is 85min when the fog dissipates naturally; 30g sodium polyacrylate whose average size is 30μm has a good effect on warm fog dissipation, t60% being 14min; when the sodium polyacrylate and sodium chloride are mixed by 1:2 in mass ratio, the fog elimination effect is the best, with t60% 6min. The reasons are analyzed at the same time.

Sr3Ti2O7ceramics with pure Ruddlesden-Popper phase (RP) were synthesized by conventional solid state method. The influences of the Bi2O3addition, the calcination temperature, and the sintering temperature on the phase transition were studied. The results showed that for the samples without doping Bi2O3, the main phase of calcined powders is Sr3Ti2O7, but pure Sr3Ti2O7phase cannot be obtained in the sintered ceramics because of the Sr3Ti2O7decomposition. For the samples doping with Bi2O3, although the main phase of the calcined powder is SrTiO3, the single RP phase Sr3Ti2O7can be obtained after sintering, which should be attributed to the formation of Sr3Bi2O6phase during calcination stage. Bi2O3addition is beneficial to the formation of the Sr3Ti2O7RP phase.

The hot deformation behavior of Ti-6Al-4V alloy with transitional microstructure over temperature 800°C~950°C and strain rate ranges of 0.001~10s-1 has been studied by Gleeble-3500 hot working simulation testing machine. The flow softening of stress-strain curves is resulted from the spheroidization of transitional microstructure, dynamic recrystallization and superplasticity. Both temperature and strain rate are important factors affecting the deformation behavior. Flow instability induced by adiabatic shear bands occurs at 800-880°Cand 0.32-10 s-1. With the increasing of strain rate and decreasing of temperature, the degree of strain localization increases. The optimum working region of Ti-6Al-4V alloy with a transitional microstructure is at 820-910°C and 0.001-0.1 s-1.

Two ashless triazine derivatives, 2,4-bi-amido-6-(O,O′-di-i-octhyl dithiophosphate)- 1,3,5 - triazine were synthesized. Their tribological properties as lubricating oil additives compared with ZDDP in hydrogenated oil were evaluated using a four-ball tester. The results show that these triazine derivatives possess extreme pressure capacity, and they can improve antiwear and friction-reducing performance of base stock than that of ZDDP. Their tribological performance is corresponding to the amide. The elements chemical states of the worn surface were estimated through X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). The results show that a protective film containing sulphide, phosphate and some organic nitrogen compounds was formed on the worn surface during the lubrication process, and the film possesses extreme pressure and antiwear properties.

Coal tar soft pitch (CTSP) used as raw material of preparing needle coke was heat-treated at 460, 480 and 500 °C for different holding time under the pressure of 0 MPa and 0.25 MPa. The changes of group compositions such as toluene solubles (TS), toluene insolubles-quinoline solubles (TI-QS) and quinoline insolubles (QI) were mainly studies during the thermal conversion of the CTSP. The microstructure morphologies of some calcined cokes were characterized by scanning electron microscope (SEM). The results showed that the thermal conversion of the CTSP had the features of consecutive reaction, and the pressure could accelerate the conversion rate of TS and TI-QS and the formation rate of QI. The calcined coke derived from the semi-coke obtained at atmospheric pressure exhibited better and longer streamlined fiber structures than that of the semi-coke obtained at elevated pressure, while the latter possessed more compact carbon structures than the former.

With the increasing of the amount of composite insulators in power network, the transmission accidents caused by the fault of composite insulators are increased and the aging of composite insulators should be paying more attention. In the paper, fourier transform infrared spectroscopy (FTIR) is used to analysis the molecular structure of silicone rubber material of composite insulators. The results indicated that the higher the electric field of the insulator shed, the lower the peak of FTIR spectra. The heavier pollution the sample run, the lower the peak of FTIR spectra. So more attention should be pay to the samples which run in heavier pollution region or the high field part of the insulator.

The effect of cryogenic treatment on the mechanical and magnetic properties of WC–6% Co Ultrafine cemented carbides has been investigated in this paper. The results show that after the cryogenic treatment, the hardness slightly increases from 1750 to 1830, however, the transverse rupture strength decreases from 2510 MPa to 2480MPa. ,the magnetization decreased from 5.82% to 5.72%, decreasing 1.71%for 24 h, but the coercive force slightly increases and reaches the maximum of 24 kA/m for 2h.

Hydroforming has many advantages over other processes, especially when runs are small and shapes are complex. The hydroforming process of automobile front transom was simulated by FEM, which is based on elastic-plastic finite element method and BT shell element theory. The effect of forming process parameters such as internal pressure loading path and initial tube size were simulated and discussed. The simulation results indicated that suitable initial tube size and loading path can observably improve the distribution of the thickness and forming limit of the tube. And for the front transom, tube size Ø55mm and bilinear loading path are the best process parameters.

Industrial AM60 magnesium alloy, to which mixed rare earth containing Y, Gd and Nd elements is added, was used to study the effects of rare earth (RE) on their casting microstructures and properties. The experimental results showed that RE could effectively improve grain refinement and the internal organization, which transferred the Mg17Al12 phase from the network structure into grainy one. The microscopic analysis indicated that by adding the mixed RE, the amount of Mg17Al12 compounds was less than that without mixed RE on the grain boundaries, and it was replaced by Al-RE compounds. In addition, the mechanical properties of the alloy with mixed RE had been significantly improved and the maximum tensile strength was up to about 260MPa and the elongation rate could reach more than 10%. When the mixed RE content was more than 2%, coarse Al-RE compounds were formed in the alloy, which degraded the mechanical properties.

Halftone is the key technique for low-resolution equipment like fax machines and printers to reconstruct grayscale images with black and white binary data. Images produced by classic error diffusion algorithm have more abundant color than those made by ordered dithering method. But the problems still exits that there can distortions and false contour phenomenon and fuzzy edges. This paper puts forward an advanced error diffusion algorithm based on bidirectional feedback and improves its feedback type through adding correction factors. The simulation results show that the bidirectional feedback error diffusion algorithm with correction factors better inhibited the phenomenon of distortions and false contour. Directional texture is also improved greatly.

Geomagnetic matching (GM) is a new developmental technology in recent years. For resolving the cumulate errors of position, velocity, attitude in an inertial navigation system (INS), utilizing artificial fish swarm algorithm (AFSA) to carry on GM is proposed, and then the attained matching position regarded as measurement of filter to achieve the emendation of INS. Firstly, affine transformation model between inertial and real trajectories is displayed and the principle of INS/GM is explained. Secondly, the state of artificial fish (AF), distance and food consistence are defined afresh, and then the flow chart based on AFSA is given. Lastly, simulation analysis is performed in actual geomagnetic reference map (GRM). The results show that the algorithm actualizes the GM when the inertial system exist position, velocity and attitude error, that is the algorithm got the optimized global solution, with that, the data fusing is finished with the results that not only reduce error evidently but also verify the validity and feasible of the algorithm.

Because of the characteristics of both one dimensional nanostructure and excellent physical and chemical properties, the kinds of novel nanomaterials-tungsten carbide nanowires, have important academic significance and practical meaning. The research development of one-dimensional nanostructured tungsten carbide is reviewed. The production methods of one-dimensional nanostructured tungsten carbide, such as nanotubes, nanorods, nanowires and nanoneedles by thermal decomposition technique, vapour deposition technique, magnetron sputtering technique, Eruptive heating technique and template technique respectively are systematically introduced. This paper summarizes the growth mechanisms and the problems involved in the existing synthesis methods. The research tendency is also forecasted.

In this study, the well logging response of CBM reservoir have been analyzed, and discussing the factors that affect the gas content of coal seam. The well logging technology has been employed in connection with log data and gas content. Take one oilfield’s well logging data for example, statistical analysis method and Langmuir equation method are selected to calculate the gas content of one coal seam, the two calculated results are basically the same, the highest value are about 26 cm3/g, is a high-yield coal seam.

Cloud computing is considered to be the next generation of IT service model, and the virtualization technology is the key technology of it.The paper focuses on the design and implementation of an intelligent cross-platform IaaS platform which is called ICIaaS. It is based on the existing open source platform technology, while its deploying and scheduling strategy for virtual machines (VMs) is self-owned. The ICIaaS is compatible with the current mainstream commercial VM, and has applied in the current research project. It is concluded that it has achieved heterogeneous virtualized computing platform integration and intelligent VM management strategy.

In view of the defects of the electric car driver motor technology, considering actual needs of the car running, relaxing the electrical power density and the limitation of the moment of inertia etc, focusing on the reliability, speed range and high efficient operation area of the motor, based on the analysis of permanent magnet brushless dc motor operation principle, this paper designed a low cost, high intelligent electric car permanent magnet brushless dc motor controller. Through the analysis, simulation, experiment and comparison, the results show that the control system has good dynamic response and steady state properties.

Night-soil pollution is a serious environmental and public health problem in highly populated and developing countries. Static and dynamic experiments were carried out to study the chroma and COD removal effect of night-soil sewage by ozone oxidation technique. The results show that, both the chroma and COD of night-soil sewage decrease with the growth of ozone dosage, and the chroma removal rate can be up to 90%, while the COD removal rate is less than 50%. The utilization efficiency of ozone decreases with the chroma reduction or the reactor diameter increasing. The appropriate diameter of ozonization reactor used in eco-friendly toilets is 150mm, and the optimal ozone dosage is 400mg/L.

A new structure of 6-RSPS simulator platform which can be rotated infinitely is presented. The solution of direct kinematics problem of parallel structure is the fundamental problem. For the solution of this problem, according to the links vector diagram, the relationship of the position and orientation of the platform between the length of links and the rotate angle of the under-hinge is derived. BP network is applied, then using the previous data obtained by inverse kinematics as the training data and testing data of BP network, the direct kinematics solution is obtained. Simulation results verified that the solution of direct kinematics applied the BP network can be meet the requirements completely and the error percentages are within the acceptable range.

Belt conveyor has the strong adapt ability and it uses widely in convey machinery. Roller is one of the key components in the belt conveyor; it plays an important role in the normal operation of belt conveyor. In order to study the influence factors of roller service life, this paper analyzed the movement of the roller and used Solid edge ST4 and ADAMS software to establish the virtual prototype model of roller and kinematics simulation of the model. This paper concludes the main factors affect the life are the sealing effect, poor alignment of the roller and the alignment of the bearing. Through the analysis of roller can reduce the design errors, improve the processing and installation accuracy mostly at the same time in the production process, it also can reduce the design and process time significantly and lower manufacturing cost and prolong the service life of roller.

Forest reconstruction was regarded as a measure of carbon sequestration and climate change mitigation. The carbon stocks in living biomass were compared between artificial measures promoting regeneration ofCastanopsis carlesii(ARC) and two adjacent plantations ofCunninghamia lanceolata(CFP) andPinus massoniana(PMP) and natural primary forest (NPF). The mean carbon stocks were about 150.1 Mg ha-1in ARC and 90.6 Mg ha-1in CFP and 83.9 Mg ha-1in PMP. The results primarily showed that the carbon stock in artificial measures promoting regeneration were higher than that two plantations. Carbon stocks in the all reconstruction of forests were all significantly lower than those of NPF (186.9 Mg ha-1), which also implies they still have a carbon sink increment potential.

Rare earth Y、Gd、Nd were added to improve the tensile strength, elongation, hardness and microstructure of AZ91D magnesium alloy in this study. The investigation had been undertaken by 8 GWU type resistance furnace, RGM - 50 electronic machine , Vickers ,etc. Results show that a moderate amount of composite adding rare earth can effectively improve the tensile strength of AZ91D alloy, elongation, hardness and the organizational structure, as a rare earth content increased after the first performance decline. When rare earth content is 1.8%, the highest tensile strength up to 276.58mpa, 8.3% elongation. When rare earth content is 2.4%, the hardness is up to 99.36 HV1.96.

Large topography can affect the global climate change significantly. Many studies have revealed that the altitude of the Tibetan Plateau (TP) is related to the Asian regional climate. In order to find how the global-scale atmospheric circulation changes in response to the TP uplift in summer, a fully coupled model, Community Earth System Model (CESM), was used in this paper. Four experiments were run with the altitude of TP set to 25%, 50%, 75%, and 100% of the modern height, respectively (referred to as TP25, TP50, TP75, TP100 experiments). The results show that the uplift of the TP causes the change of the subtropical circulation over the northern hemisphere as well as the southern hemisphere. In the TP25 experiment, the South Asian High (SAH) at the 150mb is comparatively weak, and with the elevated surface heating, the vertical motion in the middle troposphere strengthens greatly. The ascending air over the TP leads to the forming and sustaining of the SAH, a dominate subsystem of the upper troposphere. The perturbation of the SAH propagates in the upper troposphere and stimulates stronger planetary waves on the globe and it also affects the circulation in the low level atmosphere. The subtropical highs over seal level strengthen over the Southern Ocean as well as the North Pacific and Atlantic Oceans. Furthermore, the westerlies around the Antarctica become stronger with the increasing altitude of the TP. This is meaningful that the stronger westerlies may be a forcing to accelerate the Cenozoic global cooling during the geological history.

Annual mean NDVI of different Vegetation types during growing season are extracted from MODIS 8-day composite 500m reflectivity data in Inner Mongolia from 2000 to 2011 to analyze vegetation dynamic change and its spatial variation trends. It is shown that annual mean NDVI of different vegetation types has a slight upward trend during the past 12 years and the overall vegetation cover increases slightly. Area of improved vegetation is larger than degradated area and one third area basically no vegetation change, spatial pattern of vegetation cover change shows evident differences between regions.

A commercial vehicle was taken as the study object to establish vehicle rigid-body dynamics model which included seventeen-degree-of-freedom. This model consisted of three rigid bodies which were power-train, frame and body and there were flex connections among the rigid bodies. The model was used to carry out simulating calculation and analysis of vehicle ride comfort. By comparing simulation results with test results, some improvement measures for vehicle ride comfort at idle speed were presented in this paper.

This paper designed a range of 0.1 ~ 250 kHz sine wave sweeping constant current source, which sine wave generator based on FPGA chip and DDS technology, the desired sine wave frequency was obtained by controlling the frequency control words. Low-pass filter circuit was realized by using the LTC1560-1, conversion circuit from the voltage to the current was consisted of a Howland current pump. The constant current source shows a good spectral impedance purity and amplitude.

This paper investigates the dynamic causal relationship between energy consumption and economic growth in Beijing over the period 1980-2012. The Johansen co-integration test, Granger causality test and the vector error correction model (VECM) are used to calculate the causal relationship between energy consumption and economic growth. The conclusion is that there exists a co-integration relationship between energy consumption and economic growth, and this relationship is a one way relationship from economic growth to energy consumption. Further, using VECM, the long-term and short-term elasticity from economy to energy consumption are 0.43 and 0.14 separately. Statistical analysis shows that, from 1980 to 2011, every 1% growth in GDP annually would drive energy consumption increasing rate by 0.43% correspondently.

The present work investigated the effect of laser surface melting (LSM) process on micro arc oxidation (MAO) coating prepared in silicate electrolytes (Si-MAO) and aluminate electrolytes (Al-MAO). Plasma intensity of laser spots, element content and phase constituents of coatings were analyzed. During LSM remelting process, the formation of heat sources and micro molten pools on the surface of MAO coating were discussed. The results showed that the moderate plasma was formed more easily on the Si-MAO than Al-MAO coating, owing to the temperature threshold of melting oxide layer was decreased for silicon-containing MAO coating during LSM treatment. Besides, the Si-MAO coating of laser-treated had low porosity and smooth surface.

Power semiconductor device and its control circuit of photovoltaic grid-connected inverter is the weakest part in the photovoltaic generation system. Fault feature extraction is the key to the inverter fault diagnosis. Output voltage of inverter is the most sensitive characteristic quantity which can reflect its working status directly. The single transistor open fault diagnosis of photovoltaic grid-connected inverter can be achieved by extracting the output voltage frequency spectrum with the help of windowed STFT. The simulation results demonstrate the effectiveness of the method.

In this paper, a Pipeline ADC applied in medical image sensor was designed, and the analog / digital operating voltage was 3.3/1.2V respectively, the area was 0.326mm2. Because the gain bootstrap op-amp structure has been improved and the dynamic comparator was used, which reduced the overall power consumption of the ADC. The simulation results showed that in the normal working mode, the total current of ADC was about 6.5 mA; when the sampling rate was lower than 17.5 MHz, the working mode was switched to the LP (low power) mode, and the total current was 4.5 mA. In addition, the tapeout test results showed that the other performance parameters of ADC were good, the sampling rate was 35 M/s, and SNR was 58dB.

Malfunction such as target non-reach ability, local minimum pole and oscillation happens when traditional APF is applied to route planning. This paper proposes an improved APF model, considering the relative distance between the UAV and the target, the relative distance between the lead craft and the wing craft and the safety. We ensure the point of target to be the global minimum point in the entire potential fieldtarget non-reach ability caused by the threat and target point being too close are solved by adopting the modified repulsive potential function; planning failure in which UAVs falling into local minimum point is solved by adopting random fluctuation method; considering the oscillation of traditional potential field, the obstacle link method is proposed. The results of the simulation indicate the single UAV simulation route after obstacles overall planning, track route of UAV formation and formation route with obstacles with turning angle constraints. Requirements of Formation control and formation obstacle avoidance have been well satisfied.

Along with the rapid development of correlative technology in the 21st century comes the upsurge of research and exploitation for stratospheric airship around the world. In this paper, on the basis of the unique strengths of stratospheric airship, we analysed its prospects of application in the fields of communication and earth observation. Besides, we explored the status quo of development and key techniques concerning the stratospheric airship, which lead a significant role in the reference and guidance for future development of advanced information technology and building of national defence.

In order to solve the problems about picked film and tore film and kind of holes with seedlings dislocation which to be caused by the traditional film seeding machine, also to meet the requirements of planting techniques of dry-land corn whole plastic-film mulching on double ridges in northwest China. A direct insert corn precision hill-seeder with whole plastic-film mulching on double ridges was designed. By using ADAMS software to simulation research of sow trajectory about prototype hole-former, obtained the displacement curve that relative to the ground in theX,Ydirection and simulated the vertical insert of trajectory curve in the process of planting. With evaluating the working performance of direct insert precision hill-seeder with corn whole plastic-film mulching on double ridges, which to meet the requirements of agronomic techniques of dry-land corn furrow seeder with whole plastic-film mulching on double ridges.

The water environment is a system with many uncertainties and requires doing research by the method of uncertainty. Based on the dynamics of river hydrology and water quality, the uncertainty and incompleteness characteristics of monitoring information and frequency, each parameter in the model of Dillion is managed by using the theory of Unascertained Mathematics and unascertained expected value. This paper probes into the study of the permissible input of total phosphorus of Poyang Lake in Jiangxi and the credible level calculation. With this method, not only can the unascertained expected value of the permissible input of total phosphorus be calculated, its subjective reliability can also be obtained on the basis of the rules of four fundamental operations of unascertained.

The Apocynum venetum L. of Apocynaceae plant is a traditional Chinese herbal medicine. In this paper, we analyzed qualitatively the active compounds in the aqueous extract from the leaves of Apocynum venetum L. by HPLCMS and HPLCDAD. The aqueous extracts method of the mainly active compounds from dried leaves of Apocynum venetum L. was based on HPLC/DAD coupled to an electrospray ionization (ESI) interface. Overall, 8 constituents were separated and identified, which belong to flavonoids.

Boron nitride (BN) powder was modified by silane coupling agent, and a series of cyanate ester resin composites containing the modified BN were prepared. The effect of volume fraction of BN on the thermal conductivity, electrical insulation properties of these composites was investigated. Results show that addition of a little of BN powder can improve thermal conductivity of the composites effectively, while the composites still retain the relatively good electrical insulation and low dielectric constant. When the volume fraction of BN was 23.6%, the thermal conductivity of composite increased to 1.33 W/(m·K), which is 4.6 times that of pure resin.

The analytical solution to a cylindrical inclusion with an eccentric crack impacted incident SH waves was studied by using the methods of Green function and conjunction. Firstly, Green function was constructed, which was an essentical solution of displacement field for an elastic half space containing a half cylindrical inclusion while bearing out-of-plane harmonic line source force at any point of its horizontal boundary. Secondly, the whole space was divided into two parts via conjunction technology, a series of unknown forces were loaded at the linking sections to satisfy continuity conditions.Thirdly, the Fredholm integral equations of the first kind were set up through the continuity conditions and the Green function. Finally, a example for dynamic stress intensity factor for mode III at the crack tip was given. Numerical results show that the dynamic stress intensity factors is influenced by wave numbers and media parameters.

Through analyzing and comparing the treatment of fracturing fluid flowback at home and abroad, it can be found that fluid derived organic waste water can be handled by micro electrolysis economically and efficiently. But there are also some shortages of traditional micro electrolysis. So this paper discusses a new micro-electrolysis technology, namely cavitation-impinging stream electrolysis technology which has several advantages in high concentration organic wastewater treatment. The technology can not only solve the problems that the passivation of process and the plugged equipment in the treatment of fracturing fluid flowback fluid by traditional micro electrolysis, but also can better promote the reaction from the reaction kinetics with the help of Coupling application about cavitation and impinging stream technology, so as to realize the purpose of improving the reaction rate and efficiency.

This machine was for membrane covering the whole of the double furrow sowing technology and designed. They were designed to meet membrane covering the whole of the double furrow sowing technology agronomic requirements of the premise, but also to meet planting can improve efficiency, stable, reliable and cost requirements. For the above requirements, the machine used double Dibble wheel structure; field test results show that the aircraft meet the design requirements and agronomic requirements.

s: In this study, to understand the efficiency of lignin deconstruction by fungus-growing termite Macrotermes barneyi which feed on softwood only contained guaiacyl lignin, the wood metabolites in the hindgut of M.barneyi were analyzed using direct pyrolysis-gas chromatography-mass spectrometry. Significant cleavage level of propyl side-chain of phenylpropane in the hindgut was detected, and ring hydroxylation was also observed by the detection of syringal lignin. Compared with the reduction of furfural content, a pyrolysis product of pentose polymers in hemicellulose, reduction of the content of guaiacyl lignin which contained one-carbon side chain was huger in the hindgut, indicating the degradation of depolymered lignin is greater than that of hemicellulose. The analysis of lignin structure in the gut is contributed to understand the mechanism of lignin degradation by fungus-growing termite.

This paper proposes a novel fractional-order gradient operator for medical image structure feature extraction. The proposed operator can be seen as generalization of the first-order Sobel operator. The goal is to utilize the frequency characteristic of the fractional derivative for extracting more structure feature details. A thresholding is set based on the average fractional-order gradient for marking the edge points, and then the image structure can be extracted. Experiments show that the proposed fractional-order operator yields good visual effects.

Today, silicon material plays an irreplaceable role in microelectronic of the information industry, however it don`t have a good emission characteristics. In order to explore the emission character, we calculated the electrons structure, absorbance of silicon doped with C, Si, Ge, Sn and Pb by the first-principles methods.