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Ligustrum vulgare is an evergreen tree. The leaves are opposite, glossy dark green, 6–17 centimetres (2.4–6.7 in) long and 3–8 centimetres (1.2–3.1 in) broad. The ligustrum vulgare leaves contain two main components, one of which is oleanolic acid and the other is p-hydroxyphenylethanol which indicates its extracts suitable to be used as an effective corrosion inhibitor. Extracts of ligustrum vulgare leaves (PE) were modified with hydroxymethylation reaction (PM1) and Mannich reaction (PM2) to produce the relative stable green acidic corrosion inhibitors. The extracts of ligustrum vulgare leaves have been investigated on the corrosion inhibition of A3 steel with weight loss. The results show that these inhibitors have good corrosion inhibition effect on A3 steel. The PM2 are the most effective for corrosion inhibition, and the inhibition efficiency can reach 75.95%. When the temperature is 60°C, the corrosion inhibition rate of PE, PM1, PM2 is only 24.46%, 42.35% and 39.35% respectively which can not effectively prevent the corrosion of the metal. And the extracts inhibit corrosion mainly by adsorption mechanism. This adsorption accords with Langmuir adsorption isotherm.

Phosphorus scale inhibitor is a kind of agent which can disperse insoluble inorganic salts in water, prevent or interfere with the precipitation and scaling of insoluble inorganic salts on metal surface, and maintain better heat transfer effect of metal equipment. Sodium triethylenetetramine hexamethylphosphonate (TETHMPS) and tetraethylenepentamine heptagon methylene phosphonic (TEPHMPS) were prepared by one-step synthesis method. The effects of temperature, concentration and mixing ratio on scale inhibition were investigated. The results showed that as the concentration of TETHMPS and TEPHMPS increases, the scale inhibition rate increases. At the same temperature, compared with TETHMPS, TEPHMPS has better scale inhibition performance, and the maximum scale inhibition rate can reach 93.59%. The scale inhibition rate of the synthesized scale inhibitor at 80 °C is better than that at 60 °C. The scale inhibition performance of the compound scale inhibitor is better than that of the single scale inhibitor, showing an ideal synergistic effect. When the concentration is 60 mg/L, the scale inhibition rate of TETHMPS is 94.26%, TEPHMPS is 94.55%, and the scale inhibition rate is above 91%.

The assembly of different types of materials like metals and ceramics forms a structure called sandwich structure, which need advanced techniques to joint it together like the thermo compression. However, the rise of residual stress caused by the discontinuity of nature of this type of sandwich material, like incompatibility of the characteristics, which creates a risk of rupture of the structure and limited the using range of these types of materials. In this paper, we study the bonding of ceramic and metal and we will focus on the role played by the ceramic element in the stress state of ceramic/ metal interface and the stresses evaluation by Finite Element when the structure is subjected to thermo-Mechanical loading.

Compound air pollution is becoming one of three major problems of urban ecological security in China which is experiencing a rapid growth. This paper examined how to establish the "10 Portions Force" model so as to build up the promoting mechanism of government environmental regulation behaviors’ ability, which based on the time and spatial effects of China's haze pollution.

This work is part of an ambitious project aiming to manufacture epoxy-glass leaf spring by microwave processing. Physical properties of final products to be manufactured, in particular the mechanical properties, are directly dependent on uniform repartition of microwave source heating during the treatment. The major problem in microwave processing, however, is attenuation of microwave source. We propose Dielectric Effect of Attenuation Inversion of the Electromagnetic Waves (DEAI) as a new way for uniform treatment of epoxy glassmicrowave energy. This solution utilizes dielectric properties of the mold to control the microwave heat source attenuation into the composite to be treated. Electromagnetic modelling of microwave process was carried out and validated by experimental results. The results show that microwave source heating attenuation can be controlled and inversed. We demonstrated uniform treatment on epoxy-glass parts ca. 100 cm long by means of compensation of microwave source attenuation.

In order to solve fish classification problems based on acoustic scattering data, temporal centroid (TC) features and discrete cosine transform (DCT) coefficients features used to analyze acoustic scattering characteristics of fish from different aspects are extracted. The extracted features of fish are reduced in dimension and fused, and support vector machine (SVM) classifier is used to classify and identify the fishes. Three kinds of different fishes are selected as research objects in this paper, the correct identification rates are given based on temporal centroid features and discrete cosine transform coefficients features and fused features. The processing results of actual experimental data show that multi-feature fusion method can improve the identification rate at about 5% effectively.

In all process based in powder and in particular in the rotational moulding process, the major physical phenomenon during the flow of the powders is the sintering and grains growth. The sintering is the formation of only one particle starting from two or many particles under the effect of the temperature and the forces of surface tension. We interest in this study in particular at the mechanism of Polyvinylidene fluoride (PVDF) sintering. The results of this study can enable us to maximize our knowledge about sintering mechanism and enable us to determine parameters such as the speed of sintering for the optimization of the process.

The technology of NC machining simulation is a reflection in virtual environment. Machining simulation may effectively reduce the invalid feeding and probability of interference or collision between cutter and fixture due to unreasonable machining parameters. Researches on machining simulation of multi-axis NC machining are complex and representativeness. This paper took a process of surface under NX CAM environment on a non-orthogonal five axis machine tool—DMU50eVolution as the object for machining simulation, by inputting the proper engagement for the cutter, using the method of coordinate transformation to create a post processor with UG post-builder and integrated into the library of post-processing. The NC codes created have been verified in the simulation system with VERICUT. And it has been shown that the preparation time of NC machining has been reduced, the efficiency of NC machining improved and the phenomenon of collision and interference effectively prevented.

The process of the single particle through screening is researched theoretically with Mogensen screening principle. The screened particles are divided into "particle easy to screen" and "particle difficult to screen" according to the relative size and shape. Systematically analyze the factors that affect the efficiency of cylinder screening machine—the characteristics of materials’ dimension, shape features, the movement of sieve, and sieve surface obliquity, in order to realize the nuts and kinds of nuts to be graded effectively according to the size and shape. PLC intelligent control is adopted into cylinder screening machine, through the real-time detection of the speed of the cylinder at all levels and the chain transfer between the cylinders, to logically estimate the possible faults in the screening process, improving the degree of automation and reliability and safety of the equipment operation.

Proposed a concept, “cutting degree” as one of the parameters indicating the surface characteristics of the machined layer integrity. According to material nonlinearity, geometric nonlinearity, thermal coupling theory, established models of the vibratory cutting simulation, constitutive J-C model, shear model, boundary conditions, made finite element simulation of low-frequency vibration cutting by using software. Accessing to a visualization process, which is the change of material stress state in local area of the workpiece in cutting process. Analyzed the change of material stress states in local area of the workpiece, between low-frequency vibration cutting and non-vibration cutting machining process, other cutting parameters being equal. It is found that the values of cutting degree were apparently different in vibration cutting from those in non-vibration cutting. Contrasting experiments were done and SEM was observed of the machined surfaces. Findings of the experiment supported the simulation and to some extent validated the feasibility of the vision of 'cutting degree' as a term for expression of vibration cutting feature.

It’s an NP problem for distributing tools for job-shop tasks when the schedules were formulated, and it belongs to multiple-constrained and multiple-objective problem. Based on adaptive weight approach, the restriction and multiple objective problems were solved. The optimization dynamic distribution model for this problem was established. Then heuristic and self-adaptive genetic algorithm was presented. In order to express the dynamic of the distribution result, Two-dimensional coding technology was adopted, a new coding rule combining dispatching rule was designed. The results show that hybrid self-adaptive genetic algorithm based on adaptive weight approach forms well for multiple-constrained and multiple-objective job-shop tool dynamic distribution.

The extensional rheological properties of the PAN/DMSO spinning solution using ultrahigh molecular weight (UHMW) PAN as additive were studied. The effects of the additive content on the extensional rheological curve, the extensional viscosity, as well as the spinnability of the PAN/DMSO spinning solution were investigated. The results revealed that the spinnability was related to such factors as solution concentration, additive content, temperature, apparent extensional viscosity and extensional strain rate. The effect of additive on the spinnability of the spinning solution turned out to be small when additive contents were set at a very low level. The spinnability of the spinning solution was optimized when the additive content was 0.5%wt, while the spinning solution adding 1%wt additive had a good spinnability only at a relatively higher temperature.

In this paper, we present an algorithm for voice speed changing and pitch shifting based on TD-PSOLA. MATLAB simulation results indicate this algorithm can effectively improve the precision of pitch detection and convert speech into desired one. After the algorithm being realized and optimized, a real-time system is implemented on DSP, which can produce desired fundamental frequency and duration.

A concept, coupling screening, has been put forward and the method of the coupling screening is proposed based on the analysis of solo particle kinematics on flat vibrating screening and rotary screening. The kinematics model of coupling screening about solo particle has been constructed. The structure design of coupling screening machine has been done too. Eventually, with analysis of influence factors on relative geometric feature of material is carried out.

The paper made unary linear regression and structure deviation degree analyses with the data of Shanxi province in China from 1992 to 2010. The results show that when the coal output increases by 1% , the employment will increase by 1.202%. And the structure deviation degree in the coal industry fell from-0.11 to-0.56 between 1992 and 2001, then it aggrandized to - 0.15 in 2010. Which presented a note of discord surfaced during industrial structure and employment structure adjusting in Shanxi province. This suggests that there are the disguised unemployment within the coal industry. So this paper emphasizes that the government should implement the coal property right reform policy, and simultaneously develop effective measures to guide the workers to flow from the coal industry to the other secondary industries or the third industry.

The measure of the significance of the attribute and attribute reduction is one of the core content of rough set theory. The classical rough set model based on equivalence relation, suitable for dealing with discrete-valued attributes. Fuzzy-rough set theory, integrating fuzzy set and rough set theory together, extending equivalence relation to fuzzy relation, can deal with fuzzy-valued attributes. By analyzing three problems of FRAR which is a fuzzy decision table attribute reduction algorithm having extensive use, this paper proposes a new reduction algorithm which has better overcome the problem, can handle larger fuzzy decision table. Experimental results show that our reduction algorithm is much quicker than the FRAR algorithm.

Electrostatic spinning is now recognized as a versatile and easily feasible method for the preparation of micro and nanofibrous materials. Because of their high specific surface area and highly porous structure electrospun materials can find application as wound dressings that provide good draining and good air permeability [. By adding various types of material or chemical modification in electrospun materials, we can prepare a polymer with excellent antibacterial properties of nanomaterials. Copper, an inorganic antibacterial agent, is also called the second silver. The antibacterial research of copper series attracted great concern in recent years. First, the paper introduced the progress and mechanism of electrostatic spinning of native cellulose and Cu (II) ion antimicrobial fibres, and then did a brief presentation of copper ion antibacterial fibers on the bases of electrostatic spinning of native cellulose.

The paper made a regression analysis with the panel data of 29 provinces and cities in China from 1996 to 2010 based on Cobb-Douglas production function introducing the tax variable. The results show that the growth of per unit resource tax may extend the economic growth1.0325, 1.0243, and 1.0661 times in eastern, middle and western areas respectively. Meanwhile, when the ratio of the resource tax among the general fiscal income increase by 1%, the output elasticity of capital may increase by10.21%, 15.59% and 14% in tune, the output elasticity of labor may decrease by 22.02%, 17.47% and 13.95%. This suggests that from the perspective of perfecting the resource tax to study environmental tax levy can better rationalize resource price mechanism, and environmental tax is a very important economic method to carry out the stratagem of regional sustainable development, but there is unbalanced effect on different areas.

The main objective was to develop a technique by high performance liquid chromatography to study migration of contamination from packaging material of three samples of paper cups with different properties. Dibutyl phthalate (DBP) and benzophenone (BP), which are the most commonly used in paper packaging material, are regarded as stimulant of contamination, alcohol is selected as food stimulant.The obtained data indicated that migration has a relationship with the type of contamination,concentration of food stimulant.Analysed by1stOptsoftware with experimental result, the rule of migration of DBP and BP can be studied.

Pepper and Salt" phenomenon and misclassification phenomenon are serious and the accuracy is low based on pixel classification, when only use a single remote sensing image. In this article, joint LiDAR data and high resolution image together based on feature per-parcel classification,and in the image segmentation stage, texture feature is introduced, these can full use of spectral informationtexture feature and elevation information in classification, to solve same object with different spectra and same spectrum with different objects. Compared with the classification based on pixel, only use a single remote sensing image, the method based on feature per-parcel with spectrumtexture and elevation information achieved a high accuracy,96.94%, improved the classification result.

Following the test work is difficult and complex in the modern radar maintenance support, the automatic testing of radar is necessary for the radar maintenance man. Radar transmitter test device is designed to test the work state and performance parameter of radar transmitter off-line or on-line, and means while it has expert default diagnosis system to analyze the key signals and locate typical faults. The test device is accordingly seen as a good means to middle radar maintenance support. The design of radar transmitter test device is given, its hardware solution and software solution is explained. And finally the reliability and expansibility of the device is discussed at last.

The objective of this work is the study of the mechanical stress influence on the structural evolution. In particular, we studied the initiation and the plasticity mechanisms propagation of a semicrystalline polymer at small scales. The material is polylactic acid (PLA) film with average molar mass of 199 kg/mole and a thickness of 200 μm. The lamellate morphology of this material is very heterogeneous: in given area and packages of different orientation plates, they are spherulites α and β which have a different mechanical behaviour on a lamellate scale.

The boracic poly-aluminum-ferric-silicate (B-PSAF) coagulant was prepared by water solution co-polymerization method, which was synthesized from sodium silicate, aluminum sulfate, ferric chloride and sodium borate. In addition, the best molar ratio of boron and silicon was determined by single factor process. The micro-morphology and structure of B-PSAF were studied by scanning electronic microscope (SEM) and Fourier transform infrared spectrum (FT-IR). It has been studied the operation of B-PSAF as the flocculating agent, the dosage and its effects on the flocculability. Experiments show that B-PSAF is a good effective flocculant, which can be used to treat alkaline dyeing wastewater and it has the features of less consumption, rapid coagulation and high removal rate of CODCr.

Impregnation quality is vital to the whole composite. To improve it a new approach-infusion from both inside and outside at same time is supposed. Some comparison simulation studies, based on PAM-RTM software, are performed in this paper about the new composite forming method and traditional infusion method including flow behavior and filling time. Filling time via the two methods are compared, and the following results are obtained-It takes less time to fill the mold with infusion from both inside and outside at same time than traditional one; higher fiber volume fraction is, more favorable the new forming method is. The new infusion method is proved to be an effective and novel forming method about parts with high-thickness or high fiber content in composite forming area. The results will contribute to researches on the whole composite forming and bring prospect to provide more usages of three dimensional composites in high rank field.

Potential benefits of advanced composite materials, such as 3D composites, include reduced weight, superior stiffness, and good design flexibility [. 3D composites is weaved the fibers into preform firstly and then impregnated to a part. The impregnation quality is a key factor to the part performance; some imperfections resulting from it affect the integration, which limit its usages in aerospace, national defense and other areas. The infusion from both inside and outside at same time (IIOS) is suggested to improve the quality and increase the filling efficiency.

As a unique combination of science and art, digital art is impacting on the traditional art form. Digital art is actively connected with popular culture and consuming culture by the use of television, computer, Internet and other means. Digital art also has a strong influence on public culture which is successfully avoided the defects such as personal privacy and narrow sense. Digital art is an art form which is built on some certain technology conditions. However, the artistic rules of digital art works should not be less than the technical rules. After all, artists should avoid changing and covering the shallow performance of the art concept by using the digital form of technology.

As the core component of hydrodynamic variable speed transmission system of wind turbine, there exist some problems in domestic adjustable torque converter, such as simple products and poor performances. A three-dimensional flow simulation method is employed to design the adjustable torque converter. Circulatory circle is determined after the structure optimization of the torque converter. The blades are designed by the conformal projection law, and then the adjustable device’s structure is determined. The performance of torque converter with the variation guide vanes is analyzed by using numerical simulation. The calculated results show that the new torque converter could meet the needs of the wind turbine transmission system.

Take for example the BRIC economies: Brazil, Russia, India and China. We investigated the time series data on the relationship between carbon dioxide emission and economic growth in these fast-growing developing countries by both comparative statics and comparative dynamics. The results show that there is the monotonic relationship between total carbon dioxide emissions, carbon dioxide emissions per capita and per capita GDP in any one of the BRIC countries. And there is decreasing relationship between the carbon dioxide emissions per unit GDP and per capita GDP.

The transformation is implemented from short message to feature vector in this paper based on the ICTCLAS system. Then we use the kNN method to come to carry on the classified recognition to the message content, thus realizing to filter bad message effectually. The method has been testified effective in experiment.

A brand new organic cationic monomer glycidyl allyl dimethyl ammonium chloride(GADAC) was synthesized with dimethylamine, allyl chlorine and epichlorohydrin to protect the oil and gas reservoirs from damage. The effect of temperature, pH, time and the mole ratio of reactants on cationic degree of GADAC was investigated by the orthogonal design experiments and then the effect of cation concentration on the cationic degree of GADAC was also studied. The optimal condition for synthesis was gained and the product was characterized by FIRS, and the results showed that the target-product had a very good performance of anti-expansion with a very high cationic degree of more than 97%.

The crane reel is generally manufactured by section welding method when the diameter is over 380mm. With the cumulative fatigue damage principle which is based on stress S-N curve, the fatigue damage of one crane reel is analyzed by finite element method, the reel weld fatigue strength and fatigue life are calculated, and the simulation results are proved to be reliable. This method provides an efficient reference for crane reel design and residual life estimation.

Pure ZnO and SnO2-ZnO nanofibers were synthesized by electrospinning method and characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The structure and methanol sensing properties of these fibers were investigated. The results indicate that the 20 wt% SnO2-ZnO sensor exhibits considerable sensitivity, rapid response, and good selectivity against methanol at 200 °C due to the special 1D fibers properties and the promoting effect of SnO2/ZnO heterojunction structure. The methanol sensing mechanism of SnO2 -ZnO nanofibers were also discussed.

Following the test work is difficult and complex in the modern radar maintenance support, the automatic testing of radar board is necessary for the radar maintenance man. A automatic test system of radar board based on virtual instrument technology is discussed. The system used PXI bus technology and Labview program language. The design of automatic testing system is given, its hardware solution and software solution is designed. And finally the reliability and expansibility of system design is discussed at last.

Technology of pyrolysis rotary furnace for oil sludge was conducted in this paper, which feature with natural gas as fuel, multi-combuster for heating controlling and novel dynamic-static sealing structure at both ends of the rotary furnace. A complete set of technical process was designed and operated with processing scale of 10 tons/day of oil sludge (The sludge moisture content is 80%). The result indicates that the system meets the standard of safe running. Recovery rate of the oil in sludge is more than 80%, while the oil content of pyrolytic residues is less than 0.3%. The main components of non-condensable gas include methane and hydrogen, occupying 35% and 40% respectively. There are high content of lightweight fractions in pyrolysis oil, such as gasoline, kerosene and diesel oil, in which the C10-C15 is near to 50%-60% and aromatics can be up to 60％. Finally, due to the high contents of carbon and aluminum salt in residue, it is much worth for the carbon and aluminum salt recovery.

Reasonable determination of indoor ventilation rates are the main content of residential ventilation designs, and can save consumption by air conditioners. Firstly, the energy saving potential of ventilation cooling technology in Guangzhou is analyzed in this paper. The cooling load of a residential building in Guangzhou with different air exchange rates is simulated by the DeST-h after indoor heating quantity of different rooms is set. The energy saving rate is analyzed, the functional relation between energy saving rate of ventilation and air exchange rate is obtained using the linear-regression analysis method. After a comprehensive consideration of various factors, including variation of energy efficiency, room volume, air outlet size, and that the maximum air exchange rates of different rooms are fixed.

A natural mineral, palygorskite clay, was used to synthesize pure zeolite X via a two-stage method. The synthetic parameters, such as calcination, crystallization time, and SiO2/Al2O3molar ratio, were investigated. The results indicated that calcination enhanced the extraction of silica from palygorskite clay and was beneficial for the formation of zeolite X. Micro-sized pure zeolite X with the particle size of 1-4 μm was obtained in the gel with the SiO2/Al2O3molar ratio range of 1.93 to 3 after hydrothermal treatment at 80 °C for 5 h. The synthetic zeolite X showed high specific surface area (487 m2/g) and low Si/Al ratio (1.17).

A facile electrochemical approach was developed for controllable synthesis of ytterbium hexacyanoferrate(II) (YbHCF(II)) carambolalike microparticles. The prepared samples were characterized by XRD, EDS and SEM techniques. The composition of YbHCF(II) sample could be assigned to be KYb[Fe(CN)6]∙xH2O. By controlling the synthetic conditions, such as applied potential and deposition time, the size and surface morphology of the synthesized materials could be well controlled. The modified Au electrode by YbHCF(II) carambolalike microparticles possesses prominent electrocatalytic activity toward the reduction of hydrogen peroxide.

In order to improve hybrid electric vehicle’s energy efficiency, this paper did a research on the regenerative braking system of HEV. In this paper we proposed a new parallel regenerative braking control strategy for HEV and analyzed its characteristics in details. Based on theoretical analysis, we developed a parallel regenerative braking controller for a certain HEV, and built hardware-in-the-loop simulation system to test the controller’s performance. We chose the UDDS driving condition for simulation, and the result shows that the regenerative braking controller we developed is effective and reliable. The controller fulfills the parallel regenerative braking control strategy and distributes the braking force accurately. The energy recovery efficiency reaches 16.7%, which significantly improves the vehicle’s energy efficiency.

On the basis of the ball-end milling feature during high-speed machining impeller, the relationship between cutting force and chips is analyzed in this paper. The model of ball-end milling cutter cutting force is founded through differential method. And the coefficients solution of cutting force model is expounded. Besides, the coefficients solution and the cutting force model simulation are implemented by the software Matlab.

At present, in the overall quality of university education in our country, the mechanical engineering training is an important part. The actual operation of lathe is a key element in this process, and the first and foremost problem in lathe operating is security. In order to increase the personal safety of students and equipment safety, local technical transformation on CA6140 lathe was carried, including the security guards power chuck, chuck and other anti-collision travel limit. The practical application shows that after transformation, there had none of collision accidents due to unload lathe chuck wrench.