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DFT method was used to calculate the equilibrium geometries, electron structures and first-hyperpolarizabilities of grafted SWCNT (4,4) by organic chromophore stilbene at B3LYP/6-31G* level. ZINDO method was also used to calculate first-and second-hyperpolarizabilities. The calculated results show that stilbene graftings make the energy gap a little reduced and the maximum absorption wavelength red shifted, however grafting of stilbene breaks the symmetry of pure nanotube and lets hyperpolarizability increase obviously. We also found that grafting on tube mouth results in better nonlinear for their better conjugation and amide bond-linking shows bigger hyperpolarizabilities relative to direct bond-linking.

This paper discusses Radio Frequency Identification (RFID) technology and its potential applications in the asphalt pavement construction industry. RFID technology offers wireless communication between RFID tags and readers. These fundamental properties eliminate manual data entry and introduce the potential for automated processes to increase project productivity, construction safety, and project cost efficiency. Construction contractors, owners, and material suppliers that believe technology can further develop methods and processes in construction should feel obligated to participate in RFID studies for the advancement of the construction industry as a whole.

Based on the safety and durability in the complex environment, the experiments on unconfined compression strength about the cemented soil after eroding in sodium sulfate solution have been carried out and the influential laws of different concentration of sodium sulfate solution and eroding time on the cemented soil unconfined compression strength have been obtained. The test results show that the different concentration of sodium sulfate solution and eroding time may have influences on erosion effect of unconfined compression strength of cemented soil at different levels. If the ionic concentration of sodium sulfate solution is small, the solution has little erosion effect on the unconfined compression strength of cemented soil. But the unconfined compression strength will decrease with the increase of eroding time, and the erosion effect of unconfined compression strength will increase with the increase of eroding time. The study result is significant and valuable to the safety and the durability of cemented soil engineering.

During the progress of information technology and digital signal, digital signal processor has been an important discipline. The technical application in digital signal processor has already covered almost all scientific and technological fields. Because its advantages are small size, low energy consumption, high accuracy, reliable, flexible, integrated and multidimensional-using, digital signal processor take the place of analog signal system. Conception of digital signal processor is introduced, and its feature and application are summarized, also information technology has been presented. We have made solutions in information technology of digital signal processor by using DFT(Discrete Fourier Transformation), FFT(Fast Fourier Transformation) and digital filter. Actual case have been analysed. Finally we have made the conclusion.

Aiming at the shortcomings of HS Algorithm and LK Algorithm which the algotithm are too completed and the computing quliquanties are large; this paper brings forward Fast-speed Dirrerential Light-flow method, and verifies the feasibility of this mathod by Matlab Software.

The comprehensive evalution of the different plant communities diversity and degradation of Prairie Meadows. The result showed that, with the increase of grassland degradation degree, the composition of communities species was single, quantity gradually decreased, the change of species important value was obvious, the communities coverage, the communities height, ground production value was obvious decreasing trend; Plant communities a:diversity index, Margalef abundance, Simpson:advantage index Shanon-wiener:diversity index and Pielou:a verage index all have obvious decreasing, communities of similarity index has increasing trend. At the basis of indicator System fuzzy comprehensive evaluation review that the rang of indicating degree respectively:vegetation communities fence:1～0.7370,light grazing areas:0.7370～0.8117,moderate grazing areas:0.8117～0.4890,heavy grazing area:0.4890～0.

The impinging streams mixer is a new type micromixer. The cavitation phenomenon occurring in the mixers with T-shaped impinging streams (TS), conical impinging streams (CIS), vortex streams(VS) were investigated, respectively. The distribution of flow field in the mixer was simulated and calculated by commercial software Fluent 6.2.1. The results showed that under the same working conditions, a more obvious hydrodynamic cavitation may occur in the CIS type impinging stream than that in the CIS type or the VS type, and the vortex flow lead to an extension of the material residence time in the mixer. The distribution of turbulent kinetic energy and gas holdup were obtained by numerical simulating hydrodynamic cavitation under different entrance pressure conditions. It is showed that when the outlet pressure keeps a constant value, hydrodynamic cavitation can be enhanced by increasing the entrance pressure. The above research can be contributed to the producing of biodiesel and the solving of the key technical problem of oil and alcohol heterogeneous mixing.

Nanometer Al2O3 particles reinforced 7055Al composites were processed by high magnetic field with 2T,3T and 4T magnetic induced intensity (B) with constant 30 pulses. Transmission Electronic Microscopy (TEM) and X ray diffraction (XRD) were mainly used to analyze some characteristic of the treated samples. The results show that with the increase of B the dislocation density was enhanced apparently. It is deduced that plastic deformation was the main reason of high density dislocation. The magnetoplasticity effect was the source of plastic deformation.

In the TC4 titanium alloy subject to high pulsed magnetic field, the phase transformation from α to β occurs. When the magnetic induced intensity increased from 2T, 3T to 4T with constant 30 pulses, the percent of α phase adds up gradually. When the magnetic induced intensity is 4T the volume fraction of α phase amounts up to 59%. It is ascertained that magnetic field has taken a positive influence on the phase transformation because of the variation of inner energy induced by magnetic field.

Nanometer Al2O3 particles reinforced Al-Zn-Mg-Cu composites were processed by cryogenic treatment with different cycle index of 1,2 and 3. Transmission Electronic Microscopy (TEM) was utilized to analyze the microstructural evolution of the treated samples. The results show that with the increase of cycle index the precipitate amount and dislocation density have been increased. The precipitates orientation exhibits some preferred orientation. The high amount of precipitates and dislocation density and preferred orientation of precipitates will benefit to increase the mechanical properties of composites.

Al3Ti and Al3Zr particles reinforced 7055Al composites were processed by cryogenic treatment with different cooling speed at 1°C/min, 3°C/min and 5°C/min. Transmission Electronic Microscopy (TEM) was mainly used to analyze the microstructural evolution of the treated samples. The results show that with the increase of cooling speed the precipitate amount and dislocation density have been increased. The precipitates orientation exhibits some preferred orientation. The mechanical properties test demonstrates that for the samples treated at 5°C/min the tensile strength and elongation has arrived at the utmost.

The original fly ash samples fetched from the power plant and the treated fly ash samples after screening, magnetic separation and mixing were used in the experiment of photocatalytic removal on mercury in flue gas. The fly ash samples and the absorption solution after experiment were tested for mercury content. The results showed that different sizes of the original fly ash had different characteristics of photocatalytic removal of mercury. The adsorption of mercury by fly ash was an important condition for the occurrence of photocatalytic effect. When the mercury adsorption capacity of fly ash was stronger, the capacity of photocatalytic removal mercury was also greater. The presence of iron oxide on the fly ash surface can promote the capability of photocatalytic removal of mercury by fly ash. The presence of ultraviolet light can significantly promote Hg0 oxidize to Hg2+ by fly ash. Thus the oxidized mercury in the flue gas can be easily absorbed by the solution.

Three-dimensional structure model on Winkler foundation considering inter layer contact status was established. The effect that base modulus, thickness and inter layer contact status between slab and base to maximum stress of slab bottom and base bottom, shear stress between slab and base, warping of slab was calculated. The results showed that: interlayer contact status had great influence on slab stress and warping. Maximum stress of slab bottom dropped while bonding status decreased and slab warping increased obviously while bonding status weakened. Base modulus was the primary factor for base stress. Maximum stress of base bottom increased while modulus increased, and decreased while bonding status weakened. Interlayer shear stress occurred mainly at slab edge, and decreased while the bonding status weakened, almost had no correlation to base modulus and thickness.

Two methods are used to estimate the concrete strength based upon the maturity concept. The conclusion is that the apparent activation energy E value is key factor in the equivalent age method, larger value of E indicated that the age conversion factor versus temperature function is more nonlinear, and an increase in temperature results in a disproportionate increase in the age conversion factor. It is also shown that there is a unique relationship between maturity and relative strength (ratio of strength to limiting strength), and the relative strength method method-can be used in the prediction for the concrete strength.

In the rolling process, reasonable way of grading and rolling can improve the compactness and anti-permeability of roller compacted concrete (RCC), as well can make its strength meet the design requirements. Vibration liquefaction is the key step for RCC in the rolling process. Therefore, this paper first puts forward the more suitable method, Modified Vebe Vibration Liquefaction Test, to account for the characteristics of vibration liquefaction in RCC, and then, studies the coarse aggregate gradation scope using aggregate gradually filling theory. Though Modified Vebe Vibration Liquefaction Test, the research show that the aggregate VCA and the characteristics of vibration liquefaction of RCC have a good correlation. Finally, by studying the sand ratio and fineness modulus of sand how to affect the performance of liquefied RCC, the optimum value range of sand ratio and fineness modulus of sand was determined.

Concrete pavement slabs experience volume change due to the variation of temperature and moisture level. The frictional drag acting on the bottom of slab due to the base friction is in the opposite direction of horizontal slab displacement, and resist against the horizontal slab movements. The magnitude of frictional force and horizontal slab displacement has interdependent relationship. In the present study, the interface friction of typical concrete pavements was evaluated by performing a number of push-off tests. In this paper, reviews of classical friction theory and friction characteristics at the interface of concrete slabs and the underlying subbases are presented.

An exhaustive study should be carried on impermeability of crumb rubber concrete in this paper. The orthogonal experimental design method was used in mixture proportion design and considered three factors and four levels respectively. Tests were carried out to investigate the behavior of different concretes with water to cement ratio, rubber content and sand to coarse aggregate ratio (Sp). The research shows that appropriate proportional fine aggregate replaced by rubber powder can improve impermeability of concrete. Rubber content played most important role among them and water to cement ratio took second place. Sp had a little effect on permeability of rubber concrete.

AHTS is generally known as anchor handling towing supply vessels.This essay is going to discuss different styles of AHTSs modeling design with the images it conveys through the analysis of product identifications merits and drawbacks of different parts and the analysis of corrosion-resistant materials in seawater based on several types of AHTS,which aims to present a modified modeling design through a series of research. Keywords: AHTS;different parts;corrosion-resistant materials in seawater;product identification;style;imagery ;design

As an advanced machining technology, virtual manufacturing has been regarded as an useful tool to carry out analysis and research work with digital model instead of practical manufacture. For the virtual manufacturing process, it is a mapping of the practical machining in computer virtual environment, no real production is created and without material or power wasting. Several typical definition of virtual manufacturing dominate in this fields were listed out, based on which expressed an explicit interpretation. Main features and three type of virtual manufacturing, such as design-centered, machine-centered and control centered virtual manufacturing were analysed respectively. The virtual manufacturing system, supported by cutter tool magazine, pallet storage, production database, material storage and NC storage, have been demonstrated in an architecture figure. Finally, the author concluded the important role of virtual manufacturing and illustrated an example of applying virtual manufacturing in five-axis machining process.

In this paper, an experimental investigation was conducted using Vehicle Emission Testing System to study on-road gaseous emissions (CO, THC, NOX, CO2) characteristics based on diesel oxidation catalyst (DOC) and catalyzed diesel particulate filter (CDPF) technology. The results show that after the implementation of DOC + CDPF device, CO, THC emissions are significantly reduced, while the NOX, CO2 emissions remain almost the same. Under steady conditions, the reduction percentages of CO, THC, NOX, CO2 emission factors are 56.0%, 66.0%, 18.3%, 17.5%, respectively. Under transient operation conditions, the reduction percentages of CO, THC, NOX, CO2 emission factors are found to be 43.2%, 65.9%, 13.7%, 10.9%, respectively. Addition to the THC emission factor, the emission factors of CO, NOX and CO2 in transient operation conditions are higher than steady conditions.

From the RCM analysis demand of equipment, the function and constitution of the computer aided RCM analysis system are discussed in this paper. The function and composition of the database system are expounded. Meanwhile, the basic train of thought RCM analysis database system is put forward.

Directed to the problems of the military concept model in the digital battlefield, such as the indeeded definitions,the unfull contents and the non-system process.this paper defines the intension and extension of the military concept model in the war action,makes the standard contents,and definitudes the principle.at last, using the engineering science,it advances the exploiting process of models,and gives us a primary basic theories of the military concept models in the digital battlefield war action.

About the key problems of the binocular vision system design which was used to video log examining, and according to the binocular parallax theory and triangle measuring theory, the paper researched the basic principle of camera imaging, proposed the camera parameters calibration method that could determine the best placed baseline distance of two cameras and the camera focal length together, inferred the relationship of the best baseline distance and the camera focal length by analyzing to many groups calibration results. The simulation experiment results show that this method is simple, practical, and has a high precision, provides a theoretical basis for design of tow cameras positions in the binocular vision system.

A simple and practical hydraulic deep drawing test tooling is developed to investigate metal sheets formability. It is composed of two parts including the forming die and hydraulic control system. Experiments with varied material and dimensional sheets of hydraulic deep drawing and mechanical deep drawing can be fulfilled by the tooling on a Single-Action Press without complicate external hydraulic system, blank holder system and oriented system for punch, respectively. The tooling is testified to be simply, facile and reliable, which can perfectly perform the sheets forming in hydraulic deep drawing, and the formability of sheets was improved effectively with hydraulic deep drawing.

Reliability problem for gravity retaining wall constructed by new engineering materials is researched by using Monte Carlo probability theory, and the reliability program diagram of retaining wall is designed. Reliability calculation is programmed base on the anti-skid and anti-overturning safety failure mode of retaining wall. On the basis of known the probabilistic characteristics of the random parameters such as wall dimensions, material parameters, external load, and so on, and the program can automatically calculate the anti-sliding and anti-overturning failure probability and reliability indices. The research content and compiled program provide convenient reliability calculation method for the design of actual retaining walls constructed by new engineering materials.

A novel polymerizable perylene diimide electron acceptor 1,7-bis(N,N-bis(4-methoxy phenyl)aniline)-N-(3-(2-ethylhexoxy)propylamide)-N-hexyl-perylene diimide acrylate (PDA) have been synthesized, and the chemical structures are confirmed by 1H NMR and FT-IR. The PDA shows broad absorption bands in 400–850 nm, and the optical bandgap is calculated to be 1.45 eV. Cyclic voltammetry results confirm that PDA display a couple of reversible redox peaks, the LUMO and HOMO levels of PDA were calculated as -3.82 eV and -5.16 eV, respectively.

To reduce mercury emission in the flue gas at coal-fired power plant, it is very important and meaningful to research the mercury content and the existing status of other elements in coal. In this paper, mercury and sulfur content including their relevant relations of existing speciations from five coal samples were studied. Experimental method was based on U.S. EPA Method 7471 and experimental apparatus was automatic mercury analysis system Hydra AA. The results showed that in these 5 coal samples, the range of mercury content was from 0.284μg/g to 0.663μg/g and the average content was 0.401μg/g. The range of sulfur content was from 0.688% to 5.546% and the average content was 2.30% . The existing status of mercury and sulfur in coal was very complex. Under normal circumstances, when there was high sulfur content in coal, there was also high mercury content. However, the low sulfur coal may be of high mercury content.

The purpose of this paper is to obtain a start-up of short-cut nitrification systems to treat wastewater with high concentration of nitrogen and phosphorus under laboratory conditions. By starting the nitrification system at room temperature we can achieve the effective accumulation of nitrifying bacteria. Then by increasing experimental temperature and pH, and increasing the concentration of nitrogen and phosphorus in influent, to inhibit the growth of NOB in the systems and promote the accumulation of AOB. So we can make the effluent have a higher concentration of NO2--N. In the stable operation stage we can constantly improve ammonia concentration in the influent, to observe the stability of the each indicators of effluent. This experiment showed that the wastewater with high concentration of nitrogen and phosphorus can better promote the accumulation of AOB, to achieve the effect of short-range nitrification.

Electrical contractor affects reliability and working life of switches and electrical equipment directly, which is the key component of high-voltage and low-voltage apparatus. Nowadays, all fields of mid-voltage and above are occupied by vacuum switch. The invention of contactor material CuCr promotes the development of electrical contractor material and vacuum switch though the weakness can not be ignored. This paper makes a study and analysis about the performance of traditional electrical contractor material WCu. Its believed that alloy WCu has the high conductivity and high thermal conductivity of W, and the ability to improve applying condition and reduce electrical corrosion of Cu. So the experiment is made to test electrical characteristics of material WCu which is doping with different element. The performance of a new electrical contractor material, named Ti3SiC2, which is better than alloy WCu is put forward. This material meets the requirement, including high voltage, huge capacity, small scale, for switching equipment to develop grid, as the new material has advantage of low density, high modulus, high melting point, and antioxidant and so on. The successful application improves its superiority in the field of electrical contractor material.

This study compared the differential absorbance spectroscopy of the raw water oxidized with chlorine and chlorine dioxide to explore the reactions between oxidants and natural organic matter in disinfection by-products (DBPs) formation. The correlations between the differential absorbance at 272 nm (ΔA272) and 254 nm (ΔA254) and DBPs formation in chlorinated water were also examined, respectively. The intensity of the differential absorbance increased with increasing doses for both chlorine and chlorine dioxide. The sites in natural organic matter oxidized with chlorine and chlorine dioxidate are different. Unlike the well defined band at 272 nm and 254 nm in differential spectra of water oxidized with chlorine, a well defined band at 220 nm was found in water oxidized with chlorine dioxide. The behavior of -ΔA272 during chlorination process was determined to be strongly correlated with DBPs concentrations quantified by linear equations with R2 values > 0.95. A weak correlation (R2 value 254, indicating the formation of DBPs independent of destruction in UV-absorbing sites.

In this full-scale study, water treatment processes with preozonation were carried out. This work estimated the performence of preozonation of two typical kinds of surface waters in North China, Luan River and Yellow River. UV254, algae, chlorophyll a, Trihalomethanes Formation Potential(THMFP) and Haloacetic Acids Formation Potential(HAAFP) were investigated. In addition, formaldehyde and bromate, which are the main ozonation by-products, were also measured. Results showed that preozonation played an important role in reducing algae, chlorophyll a and UV254. About 33% of THMFP and HAAFP were removed by preozonation. Moreover, the processes applied in this study with preozonation were applicable to different raw water, and the water quality of the effluent was greatly improved. In the final effluent, half of the THMFP and HAAFP were removed. Formaldehyde and bromate were both below the limits(900 μg/L and 10 μg/L, separately).

Building space cooling load affected by lots of factors,was transient, multi-dimensional and highly interactive. A model of online least squares support vector machine (LS-SVM) was established to forecast the space cooling load of building, and correlation analysis was used to find out the main influencing factors, such as, dry-bulb temperature, solar irradiance, and so on. As an example, the hourly space cooling load of an office building in shanghai was investigated. The hourly space cooling load was firstly calculated by the simulation software of DEST, and then, an online LS-SVM model was presented to forecast the load. The simulation results showed that the online LS-SVM model was effective for space cooling load prediction.

Porous asphalt pavement (PAC) is constructed with an open-graded porous mixture with 15–25% designed air void and 4–5 cm surface thickness. This paper presents paving material selection and requirements of porous asphalt concrete in the cold regions. Through a series of laboratory tests, optimum gradation of the aggregates and bitumen content (BC) were selected, which met all aspects of performance indexes. Uniform experiment design methods, including Marshall test, immersion Marshall test and Freezing–thaw indirect tensile test, were applied to analyze road performance of PAC, such as temperature stability, water stability, resistance to Freezing and thawing and so on. The results confirmed that PAC studied is an effective pavement surfacing materials in cold climate regions.

Against the background of shenyang subway shield tunnel construction, the method of numerical simulation methods are used to analyze the factors of surface subsidence caused by shield construction comprehensively, and the universal finite element program ABAQUS is used to establish mechanical model depended on comprehensive consideration the influence factors of soil warehouses pressure, seepage and groundwater. A dynamic finite element simulation of shield advance process and conclude the surface deformation rule of soil are studied.

The fracture process of concrete structures is a very complex process, which includes the crack initiation, cracking, expansion and unstable failure. Based on the analysis of existing fracture criterion theories and some experimental data, this paper proposed the strain-energy criterion of I so-line for mixed mode crack in concrete. This formula is easy to be deduced, clear in physical concept; besides, it predicts the crack initiation angleθ0and determines propagation of the crack. The guidelines of the theoretical predictions are consistent with the measured results, which show that the guidelines can be applied to analysis crack problems of concrete I-II mixed mode fracture.

The energy efficiency reformation of existing buildings is a very complicated system which is controlled by lots of factors. It is very important content of the energy efficiency reformation work. The evaluation system for energy efficiency reformation of existing buildings is established. The value assignment method is proposed and the rating standard is established. Based on matter-element theory and dependent function, the extension theory is applied to evaluate the effect of energy efficiency reformation of existing buildings, and the extension method for the effect evaluation is proposed. Taking a real project of energy efficiency reformation for example, based on the reasonable selection of evaluation factor, an extension model for evaluation is built. As a result, it is practical and feasible to apply the extension method to solve this kind of problems.

In order to study the bearing capacity conditions of the reinforced concrete structure in service in the phase of using,test the mechanical properties of the bending members of reinforced concrete structures under loading and not loading conditions,and compare and analyze the relationship of load and deflection, crack, steel strain,concrete face strain under the two conditions,has got the conclusion that the bearing capacity decreased almost 12% under holding load, and analyze the effect of the bearing capacity and deformation under holding load; use ABAQUS finite element to simulate bending members of reinforced concrete structures under holding loading,and the simulation values are very close to the experimental results; indicate that finite element simulation can be carried out in prediction the service life of reinforced concrete structure in practical engineering.

Increasing requirement of MCMnFe & MCCrFe in steel enterprises, the applying of the shaking ladle process is also adapted by more and more ferroalloy enterprises. Changing the speed of rotation, the phenomenon of the oil/-water interface motion is investigated by simulation test under the different eccentric distance, volume ration of oil to water, and speed of rotation. The results show that with the same ladle diameter and eccentric distance, and the increase of the speed of rotation, the state of Oil/Water interface motion is changed from oscillatory motion to lotus-leaf state motion, and finally the emulsifying state motion. Among the three states, the emulsification state is the required movement with the full agitation and fast mass transfer speed. The more the eccentric distance and the less Voil/Vwater, the less the critical speed of rotation is, and vice versa.

In this paper, electrolysis and hypochlorite oxidation methods are adopted for the preparation of potassium ferrate, focusing on increasing the production yield and product’s purity. The oxidation of benzopyrene by potassium ferrate was investigated. The yield of potassium ferrate prepared with hypochlorite at optimized conditions is 21% higher than that of using electrolysis method. With the presence of hypochlorite, various conditions of oxidation reaction were determined as following: reaction temperature 25°C, re-crystallization temperature of -5 °Cand reaction time 40 minutes, which all contribute a yield of 80%. Spectrophotometric was used to analyze the purity of the product, which was measured up to 97%. XRD and IR were used to characterize the final product. The aqueous stability of potassium ferrate at various pH values was investigated. It was found that potassium ferrate solution had a maximum stability at pH 9-10.5. With three-dimensional excitation emission matrix fluorescence spectrosopy technique, the reaction of ferrate and benzopyrene (BaP) in aqueous phase which is a representative polycyclic aromatic hydrocarbon, was also investigated. The maximum degradation (49.5%) of BaP was gained at conditions of pH 9.5, Fe(VI): BaP molar ratio of 1:5, reaction time of 3 hours.