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In this paper, from the standpoint of Raman spectrum research aspect in material science, Raman spectrum analysis of graphite and diamond microcrystal retained by gallium phosphide nanoparticles is introduced. We found that molecular configuration of basic fuchsin adsorbed on gallium phosphide nanoparticles through experiments. Based on these, Raman scattering is used for analyzing basic fuchsin adsorbed on surface of gallium phosphide nanoparticles. Moreover, we discuss the corresponding meanings of agglomeration phenomenon from the perspective of material.

(2-one-1,3-dioxolan-4-yl) methyl 3-mercaptopropanoate(DMMP), which can be used for Michael addition reaction, was synthesized through two simple routs. First, glycerol carbonate was synthesized under mild conditions without any solvent, using glycerol and dimethyl carbonate as raw materials by green chemistry way. Then DMMP was obtained by simple esterification reaction of glycerol carbonate and 3-mercaptopropionic acid. The structure of them was characterized by 1H NMR and FTIR.

PbS quantum dots/ Boron and Nitrogen co-doped TiO2 photocatalyst emulsions were synthesized by a complexation-controlled hydrolysis method at room temperature. Boron compounds and Nitrogen compounds were added to TiO2 precursor solution, and PbS quantum dots were attached to TiO2 particles surfaces by using chemical reaction. The hybird composite photocatalysts were characterized by nanoparticle size analyzer. Their photocatalytic properties were evaluated through the degradation of acid red 3R dye. The results indicate that when TiO2 emulsion added to Boron ions, Nitrogen ions, and PbS quantum dots, the reflux time is 15 min, the photocatalytic performance of the emulsion is the best.

A numerical study was conducted to examine the flow field around and heat transfer from an elliptical cylinder of AR=0.5 in two types of the annular boundary and rectangular one. The fluid near the surface separates from the cylinder surface and forms a steady recirculation bubble at the rear end of the cylinder at the first critical Reynolds (Rec1). The vortices begins the alternating separation at the second critical Reynolds (Rec2). Rec1 and Rec2 for the fluid in two boundary types are studied. The Nusselt numbers are compared at Rec1 and Rec2 respectively.

These paper investigated the relationship between economics development and energy demands based on Energy Kuznets Curve (EFC) in China. The results show that, the prospects of economics and energy demand in China in further will undergo three important stages to 2050.The peak of energy demand maybe around 2035 and the corresponding total energy demand maybe amount 5.7 billion tce. In 2035, the GDP per capital maybe about 17000 (2005 US$) and the urbanization will reach a relative high level. It is urgent for China to take actions to curb the increasing total energy consumption.

Linkage can realize complex motion law, butunder the condition of running at high speed, institutions, thedynamic elastic response of not only make the institutions of trajectorydeviation, also can cause fatigue failure. In this paper, we study the basiccharacteristic of the four-bar linkage, affect the motion law of severalparameters was analyzed.

The irradiation degradation of selected estrogens quinestrol (QS) , norethindrone (NET) and dienestrol (DS) were evaluated by electron beam . Processes using electron beam can efficiently degradate QS, NETand DS, usually at reaction dosage lower than 6KGy. Especially remarkable is the high degradation efficiency shown by oxygen saturation which is extremely favored by acidic environment. The order of the degradation rate: DS > NET> QS by different analysis methods such as HPLC. Among electron beam irradiation carried out, higher removal of 90% from solution was observed. In addition, the estrogenic activity of QS, NET and DS was carried out by rotifer test.

Charge density wave theory is used to investigate the dependence of dielectric loss of relaxor ferroelectrics on temperature, frequency and concentration of impurities. The dielectric loss originates from the local pinning. The competition between the local and collective pinning leads to a peak in the curve of dielectric loss v.s. temperature as well as the curve of dielectric constant v.s. temperature. The peak temperature of dielectric constant TL, increases with increasing frequency and with decreasing concentration of impurities. The maximum dielectric loss is in proportion to TL and in inverse proportion to the barrier height. Our theoretical results agree qualitatively with the experimental results.

The new kind of bio-based nylon 56 fiber has been synthesized by adipic acid and 1,5-pentanediamine, which was prepared by fermenting a variety of starch in straw. The resistance of the nylon 56 fiber to acid need to be studied because the problem of nylon fabrics often encounter reactions of chemical reagents in their processing, finishing and dressing. The factors of acid concentration, temperature and time affect the mechnical behavior of the fibers of nylon 56 ,nylon6 and nylon 66. Strength of all three nylon fibers have obvious decrease if treated in acetic acid concentration of 10 g/L, while have a straight line down if treated in acetic acid concentration of 100 g/L as time increases until to a half falling down at 120 minutes. Bio-based nylon 56 fibers treated in acetic acid concentration of 100 g/L for 30 minutes have a sharp reduction and almost lost its function at 50 minutes.

Effects of the distance between guided needle and cone body on properties of MVS yarns were investigated by numerical simulation. 5 groups of the distance are designed (0.5mm, 1mm, 1.5mm, 2mm and 2.5mm). The 3D computational fluid dynamics models are established to conduct the numerical simulation of the airflow in the nozzle. Through analysis of the characteristics of air flow inside the different nozzles, such as pressure distribution and velocity vectors, the motion of drafted fibers and performances of yarns are discussed. Simulation results show that when the distance is 1.5mm, the airflow state within the nozzle is beneficial to form more open-ends and twist, and the yarn quality would be better.

Remote fault diagnosis in order to realize the mining enterprise equipment requirement, reduce the cost of fault diagnosis system based on VPN remote fault diagnosis system scheme is put forward. VPN technology to establish the enterprise network system, it is reasonable to implement remote connections between corporate headquarters to the mines. It can always track the running status of equipment working in the field of improving customer service response speed. Users can use it to avoid safe hidden trouble, as far as possible to shorten downtime, increase productivity. Field operation shows that our designed system can quickly diagnose the cause of the problem in time to provide a good reference.

The flesh firmness of AC andrinmutant tomato fruits picked freshly were the largest. Respiration rate and ethylene production were very low at this time. With ethylene production increase, fruit firmness began to decline. 100μL/L ethephon significantly increased AC tomato fruit ethylene release, respiration rate, ACS activity and ACO activity, and decreased flesh firmness. However, there were no significant differences inrinmutant between control and ethephon treatment. It was shown RIN transcription factor regulated ethylene biosynthesis by ACC synthase and ACC oxidase.

The influences of 1-MCP on AC tomato fruit softening were investigated. Ethylene production, flesh firmness, protopectin content, soluble pectin content and polygalacturonase (PG) activity were used to evaluate the quality of tomato fruit. It was shown that 1.0 and 1.5 μL/L 1-MCP treatment significantly decreased the levels of ethylene production, and inhibited flesh firmness and protopectin content decline and polygalacturonase activity increase. At last, it was concluded 1.0 μL/L 1-MCP treatment on AC tomato fruit was the best determining economy.

Aiming at the file transmission problem between electronic controller for an engine and the portable test equipment based on AT91SAM9263 and Linux, the Interlnk/Intersvr software and their communicating protocol are analyzed and studied which used by electronic controller. The message format and communicating process are made clear by putting up protocol analysis environment at laboratory and source code analysis, FAT file system structure and its access methods are studied, and the file transmission function of test equipment has been fulfilled. The results of test indicate that the desired goals have been reached.

In order to improve the spinnability of flax fiber during alkali treatment and save reagent, the effects on the properties of flax fiber are studied under the condition that both ultrasonic and NaOH reagent. It was observed that in the process of alkali treatment to flax fiber, it was better than use ultrasonic when it comes to the length, splitting degree and short fiber content. During the process of alkali treatment, the processing effects were good when the temperature was 50°C, time 30min, frequency 28kHz, concentration of NaOH 10%. Not only the spinnability of the flax fiber is improved with the use of ultrasonic, but also the problems high consumption of time, and pollution are solved.

The combined blowing process of metallurgical multiphase reactor was simulated by water modeling. The effects of operation conditions on dispersed phase size distribution were studied and an empirical formula was obtained. Based on the law of additive codimensions, the interface areas under different operation conditions were calculated by means of box counting and projection relationship. The results show that the frequency of dispersed phase with certain granularity level are in a certain proportion to its size level, and the dispersed phase areas are influenced by the top and bottom combined blowing.

The new kind of bio-based nylon 56 fiber has been synthesized by adipic acid and 1,5-pentanediamine, which was prepared by fermenting a variety of starch in straw. The resistance of the nylon 56 fiber to acid need to be evaluated because the problem of nylon fabrics often encounter reactions of chemical reagents in their processing, finishing and dressing. Temperature and concentration play the main role on the alkali resistance among the factors that influence alkali resistant of nylon fibers: temperature, time, and concentration of alkali. Strength lose of bio-based nylon 56 and nylon 6 are slightly larger than that of nylon 66 when treated in caustic soda of 100 g/L at 98°C for 120 minutes, which means that nylon 56 fiber have good alkali resistant.

Seismic inversion methods include constrained sparse pulse inversion and band limit inversion, etc. Although resolution of the seismic inversion results is higher than seismic data, it does not identify thin interbedding sand body and confirm the development of reservoirs. In this paper, in A block of Indonesia adopted geostatistical inversion in reservoir prediction, which is a method of seismic inversion combining geological statistics simulation and seismic inversion. This inversion method can establish various 3D geological model with the same probability of rock properties and lithology and it obey all seismic, logging and geological data. Using statistical regularity and seismic inversion technique we can obtain more fine reservoir model and finally reach the purpose of identification of single thin sand layer.

The typical characteristic of stoning band coal seams is of multi-layers and low permeability, so fractured vertical well is usually used in the CBM development of this kind of coal seams. As far as the reservoir simulation of vertical fractured CBM wells is concerned, the fracture characterization technique is of great importance. Taking the vertical fractured pilots in F coal measures of Bowen Basin in Australia as an example, this paper will illustrate the application of fracture characterization technique in reservoir simulation. Its highlight is to scientifically characterize the shape of hydraulic fractures and quantitatively describe the reservoir permeability improvement after fracturing through “MULTX” of grid conductivity with Tartan grid model, thereby determining key parameters for the reservoir simulation of fractured vertical wells and providing a scientific basis for establishing CBM development plan and forecasting ultimate recoverable reserves.

SIS well is a successful technology for coalbed methane development. In this paper, the drilling and completion technology were introduced systematically on the aspects of optimization design of well profile, drilling equipment, drilling and completion technology of vertical well and horizontal well, and intersection technique of these two wells. Two new well patterns, i.e., commingled well and boat-shape well were also proposed. When application this technology to other areas, some improvement may should be made according to special geological data.

Coal bed methane (CBM) is a kind of natural gas that generated from coal and disseminated organic matters during the stage of diagenesis and coalification, which mainly composed of methane and hosted in coal seam by free, adsorbed, and dissolved forms. Genetic, reservoir type and occurrence condition in CBM are different from traditional reservoir. And the high-produced development wells in CBM aiming to drill more coal seams with high quality therefore needs to be analyzed in the methods that are different from traditional reservoir. 3 important factors including the study on correlation and elevation depth of coal seam roof and floor in section and areal by using well-seismic ties, outcrop boundary based on coal mine data and distributions of CBM reservoir properties in 3D model are needed for high-produced development well analyze in CBM. Application in Australia CBM project shows this methodology is very successful for the development well design with high production.

Based on the analysis of coring, logging and experimental data, fine evaluation on Fort Copper Coal Measures (FCCM) of Early Permian Blackwater Group in north Bowen Basin of Australia has been done. FCCM is a potential coal measure. Eight coal seams exist in FCCM. Laterally, they develop steadily. Seams of FCCM characterize interbedding with partings, high ash content, high gas content and mediate-low permeability. The content of partings, which are groups of siltstone, mudstone and tuff, ranges from 15% to 55%. The cumulative thickness of pure coal ranges from 40 to 60 m. The ash content ranges from 20% to 70%, averaging 45%. Coal seams gas content is as high as 7% to 15%, benefitting from the dense rock block effect on the top and bottom, as well as the interplayers. The permeability ranges from 0.1 to 10 mD laterally. Parameters above show FCCM has good developing potential. Western slope of Nebo syncline is suggested as the favorable area, considering its good developing factors such as shallow buried depth of coal seams, relatively high permeability and effective gas preserve environment. Meanwhile, gas in partings can be considered in collaborative development strategy. Developing gas along with ash will be the focus of future development evaluation.

This is a report on the performance of 4 types of cool roof system through field tests. Cool roof means solar protection on roof surface [1]. The tested systems were solar cells as a shading device, several types of thermal insulation paint as heat reflectors, a rooftop garden as an outside thermal insulator on a roof and a water pond on a roof as a coolant with sensible heat and evaporation. The test results indicated obvious temperature difference between the cool roof and the ordinary surface. The heat flux was calculated from the results to estimate the cooling load saving. Finally, these results were examined from the viewpoint of cost performance.

A self-study harmony search (SSHS) algorithm for solving unconstrained optimization problems has presented in this paper . SSHS employs a novel self-study strategy to generate new solution vectors which can enhance accuracy and convergence rate of harmony search (HS) algorithm. SSHS algorithm as proposed, the harmony memory consideration rate (HMCR) is dynamically adapted to the changing of objective function value in the current harmony memory. a large number of experiments improved that SSHS has demonstrated stronger convergence and stability than original harmony search (HS) algorithm and its two improved algorithms (IHS and NGHS)

Aiming at the characteristic of medical images, this paper presents the improved genetic simulated annealing algorithm with K-means clustering analysis and applies in medical CT image segmentation. This improved genetic simulated annealing algorithm can be used to globally optimize k-means image segmentation functions to solve the locality and the sensitiveness of the initial condition. It can automatically adjust the parameters of genetic algorithm according to the fitness values of individuals and the decentralizing degree of individuals of the population and keep the variety of population for rapidly converging, and it can effectively avoid appearing precocity and plunging into local optimum. The example shows that the method is feasible, and better segmentation results have got to satisfy the request for 3D reconstruction, compared with k-means image segmentation and genetic algorithm based image segmentation.

The NURBS curve interpolation algorithm based on parabolic interpolation error and the first-order Taylor expansion interpolation algorithm is proposed to improve part surface quality and chord error of NURBS curve interpolation algorithm. The part surface quality is improved effectively by the parabolic interpolation algorithm in the conduction that the previous point, the current point and the next point which was computed by the first order Taylor expansion interpolation algorithm were known. The effectiveness of this algorithm is proved by the NURBS curve interpolation simulation.

According to system dynamics and in-tree structure, we choose National Transport & Logistics Public Information Platform (LOGINK) as a research object. Then, considering new service concept, new customer interface and new delivery system, its dynamic mechanism of service innovation is studied. Finally, we establish the corresponding dynamic relationship model and deduce dynamic relationship equation.

Vanadium/iron co-doped nanoTiO2 transparent hydrosol with an average particle size of 3.8 nm was synthesized by a novel complexation-controlled hydrolysis method at room temperature and atmospheric pressure by using TiCl4, ferric nitrate, ammonium metavanadate, etc. as raw materials. The composition, phase structure, particle size, absorbance spectrum, and photocatalytic performance of samples were characterized by XRD, EDS, nanolaser particle size analyzer, and UV-Vis spectrophotometer. The photocatalytic properties of V/Fe doped TiO2 were studied through degrading acid 3R dye, and the results show that when the content of V/Fe was 0.5%, the degradation rate reached more than 96% under irridation for 60 min.

Pluronic F87/Poly (lactic acid) block copolymer (PLA-F87-PLA) was synthesized by bulk polymerization. Paclitaxel-loaded PLA-F87-PLA nanoparcticles were prepared by a dialysis method. The loading efficiency was determined by UV. The results showed that the loading efficiency of paclitaxel for PLA-F87-PLA nanoparticles was 69%. In vitro release behavior of paclitaxel-loaded PLA-F87-PLA nanoparticles was studied by HPLC. In vitro release behavior showed an initial rapid release followed by a slow release. The biocompatibility of nanoparticles was measured by MTT. The viability of paclitaxel-loaded PLA-F87-PLA nanoparticles was less than that of free paclitaxel. The results indicated that PLA-F87-PLA copolymer has good biocompatibility.

For coping with modern thermal infrared reconnaissance, thermal infrared camouflage is becoming the hotspot of camouflage pattern research. Concerning the traditional methods on evaluating ground thermal infrared camouflage can’t solve the “dynamic” problem and the pure technical as well as pure scale efficiency. This article established new models to figure it out. The new measure introduced time parameter to construct dynamic model, then it set up pure technical dynamic DEA model which supposed it had variable returns to scale. Through the relationship among technical, pure technical and pure scale DEA model, we can get the pure scale dynamic DEA model. Finally, an example was calculated which shows the application of the new models.

The effect of carboxyl density (the ratio of acrylic acid and polyoxyethylene ether) upon the performance, molecular weight, and monomer conversion rate of polycarboxylate (PCE) were investigated by slump test, Gel Permeation Chromatography (GPC) and High Performance Liquid Chromatography (HPLC), respectively. The results showed that with carboxyl density increased from 2:1 to 7:1, molecular weight of PCE increased from 7968.5 to 13930.1 and the molecular weight distribution coefficient increased from 1.5 to 2. The HPLC date indicated carboxyl density does not affect the rate of monomer conversion. Test of the fluidity of cement pastes displayed that as carboxyl density was 4.0:1, PCE show the optimal dispersion and dispersion-retaining ability.

In this letter, an optimal power allocation in the two-way relay channel of four transmission nodes employing the physical-layer network coding (PNC) protocol is proposed to improve the network sum-rate of the two-way relay system. The optimal power allocation is obtained by maximizing the network sum-rate of the PNC protocol under a sum-power constraint in a Rayleigh fading channel environment. Analytical and simulation results show that the proposed power allocation can improve the network sum-rate. Furthermore, compared with the equal power allocation scheme, the proposed power allocation scheme can achieve much higher network sum-rate performance.

A combined process of coagulation with Fenton oxidation was introduced to the advanced treatment of the secondary effluent of a pharmaceutical wastewater treatment process in northern China. Major factors affecting the treatment were investigated by lab-scale tests. The results showed that FeCl3 was the best among the tested 4 coagulants, and its optimal dose and the initial pH for reaction were 175 mg/L and 7, respectively, at ambient temperature. After the coagulation, the wastewater was treated by Fenton oxidation. An excellent treatment efficiency was obtained with H2O2/Fe2+ (M/M) of 7.5 and H2O2 dosage of 10 mM/L at 20°C reacting for 60 min. For the influent with a COD of 170~200 mg/L and a TP of 6~9 mg/L, a COD removal and TP removal as high as 71.5% and 99.5%, respectively, could be reached after treated by the coagulation combined with the Fenton oxidation under the optimized condition. The final effluent could meet the requirement of Discharge Standards of Water Pollutants for Pharmaceutical Industry Fermentation Products Category (GB21903-2008).

In the article the flow field in the twin-tangential annular flow gas distributor was simulated based on the standard k-ε turbulent model with FLUENT software according to various distance L between sleeve and column wall and differing numbers of baffles, after comprehensively analyzing, got the best technological parameters with misdistribution factor and pressure drop. Based on the analysis of the flow field discipline of the twin-tangential annular flow gas distributor and the two-line vane gas distributor, and the systematic comparison of the performance of these two kinds of gas distributors in the flue gas CO2 absorption column, the research will provide the important theoretical foundation for the choosing and designing of the distributor of the flue gas CO2 absorber.

Panorama image can provide 360 degrees view in one hotspot, which could solve the traditional three-dimensional expression of inadequate authenticity, difficult data acquisition as well as laborious and time-consuming modeling. However, we need other geographic information. So we propose a kind of integrated model based on GML, which contains a set of data structures to obtain panorama, terrain and 3D Data rapidly from the GML file, after analyzing GML files structure and parsing by the Document Object Model (DOM). The experiment shows that integrated model is very validated in web application using PTViewer, Java 3D and Web-related technologies.

Design and analysis of computer experiments (DACE) can solve the optimization design problem for stationary platen effectively. In this paper the method of uniform design is applied to obtain the design of computer experiments which is employed in the optimization design of the stationary platen. 3 factors (11 levels for each factor) are selected. The approximate Kriging model is built on the basis of the FEA results. 10 design points are selected randomly to verify the prediction ability of the Kriging model. The results show that the maximum of the relative error is 2.53% and the minimum is 0.63%. The approximate model built in this paper is practical in the optimization design of the stationary platen. The steps proposed in this paper are also suitable for the optimization design problems with complicated geometry or finite element model.

Quality of soil reconstruction is directly related to the vegetation recovery of opencast coal mine in loess area, therefore, research on soil properties of land reclamation has a very important role in mine ecological recovery. Based on an reclamation open coal mine dump loess area as the research area, semi-variance function as the basic tools, combined with traditional statistics and geo-statistics method, with statistical module of arcgis10.0, was applied to study the spatial variability of 0 ~ 40cm soil granules in early stage of reclamation, and using ordinary kriging method to draw the spatial distribution map of different particle size of soil granules. Results show that: (1) in early stage of reclamation, between 0 ~ 20 cm and 20 ~ 40 cm the component characteristic of different size of soil granules was similar, the average of silt content was all highest in the whole research region .(2) through the semi-variance function fitting, the theory model of semi-variogram of clay accord with spherical model, the semi-variance function of silt content in 0 ~ 20 cm level in line with the spherical model, in the 20 ~ 40 cm accord with the exponential model, the semi-variance model of sand in 0 ~ 20 cm fit with the spherical model, in the 20 ~ 40 cm semi-variance function in line with the exponential model, different size of soil granules content has spatial auto-correlation in a certain range, showing that has a medium spatial correlation. (3) the map can reveals the spatial distribution of soil granules in different levels, in 0 ~ 20 cm, on the horizontal direction of silt content in the high value area in the study area corresponds to the sand content is low in the area, both of them have good complementary, and in the vertical direction different soil granules content in the spatial distribution has no obvious regularity. This study can provide certain reference for loess area land reclamation of soil profile reconstruction and soil fertilization and amelioration.

In this paper, the model of low temperature fractionation CO2 capturing process is established with HYSYS to carry out the simulation of the process. According to the simulation results, it is concluded that as the CO2 content in the feed gas raises, the CO2 product purity increases and the cooling energy cost of the system decreases. As the CO2 product purity rises, the cooling energy cost increases more and more rapidly. According to the 91.0% CO2 content feed gas, the optimized fractionation pressure is 3.1MPa and the corresponding liquefaction temperature and condensing temperature is-20°C and-24°C respectively.

Laser direct-part marking is finding increasing use in the tracking of products as they pass through a manufacturing process. But too high heat input of the laser may cause deformation of the product beyond the limit of the drawing. In order to investigate the effect of laser marked Data Matrix symbol on titanium alloy, a Q-switched lamp pumped Nd:YAG laser was used in this research. Two Data Matrix symbols using 16A and 28A of electric current were marked respectively in the center of two titanium alloy sheets with 50mm length and 50mm width and 2mm thickness. To analyze the quality of the laser marking, environmental scanning electron microscope (ESEM) and X-ray diffractometer (XRD) were used. Experimental results showed the HAN’S Q-switched lamp pumped Nd:YAG laser marking system did not cause damage to the titanium alloy.

The future development of tourism marketing should focus on marketing model for the Chinese market through the use of reasonable technical, find a more accurate, more effective way of marketing to product higher profit margins, but also provide more personalized of the product for consumers, and ultimately achieve long-term growth of tourism economy.This paper discuss the innovation of e-commerce tourism in following four aspects: the innovation of marketing model based on travel agency characteristics, the application of marketing method based on media characteristics, The evaluation innovation of travel agency based on marketing mix model and the innovation of marketing model of travel agency.

In this paper, we employ iterative analysis method of applied-information technology to obtain both the existence and the stability of first order functional differential equations with impulses for periodic boundary value problem. Some new results are obtained.

The magnetic properties of Co-P films with different structure depended on the temperature were investigated. The Co-P films happen to the transition from the weak ferromagnetic to the strong ferromagnetic at lower temperature. At higher temperature, the Co phase transformation from HCP to FCC crystal structure results in a sudden change of the magnetization of the nanocrystalline Co-P films. For the amorphous Co-P films, the occurrence of the crystallization at 610 K leads to a magnetization transition. The first-principles calculations shows that the intense exchange coupling of Co-Co and Co-P atoms from the Co and the Co2P phase contributes to the magnetic property.

In this paper, the concept of (G) fuzzy integral on a fuzzy set is given and the basic properties of it are discussed. Monotone Convergence Theorem and Fatou Lemma are proved. Finally, A necessary and sufficient condition on which (G) fuzzy integrals of two fuzzy measurable functions on fuzzy sets are always equal is given.

To identify critical laser marking parameters which have a statistically significant effect on the contrasts of laser marked Data Matrix symbols on titanium alloy substrates, a Q-switched Nd:YAG laser was used in the laser marking process. The influence of six laser marking parameters (i.e. electric current, effective vector step, delay between the effective vector step, Q-switch frequency, Q release time, and laser line spacing) on the contrasts of laser marked Data Matrix symbols were studied. Single-factor analysis of variance(ANOVA) tests with a 95% confidence level were employed to determine whether a laser parameter had a statistically significant impact on the contrasts of laser marked Data Matrix symbols. Experimental results showed that four laser marking parameters (i.e. electric current, effective vector step, Q-switch frequency, and laser line spacing) have a statistically significant effect on the contrasts of laser marked Data Matrix symbols.

To determine the impact of laser parameters on the contrasts of laser direct marked Data Matrix symbols on titanium alloys, a Q-switched Nd:YAG laser was used in the marking process. For this purpose, four laser marking parameters (i.e. electric current, effective vector step, Q-switch frequency, and laser line spacing) were correlated with the symbol contrast (SC). The L25 orthogonal array based on the Taguchi experimental method was adopted to determine the optimal combination levels of laser parameters for the SC, and the experimental data were statistically analyzed by multi-factor analysis of variance (ANOVA). Experimental results showed that the electric current, effectie vector step, laser line spacing have a statistically significant impact on the contrasts of laser marked Data Matrix symbols. Q-switch frequency is statistically insignificant at a 5% level. The optimal combination levels of laser parameters for the SC is where the electric current is at 26A, the effective vector step is at 0.001mm, the laser line spacing is at 0.01mm, and Q-switch frequency is at 5kHz.

This paper focused on the influences of different coal macrolithotypes on the coal reservoir properties, using a variety of testing methods studied the connection between macro-lithotype of coal and properties. When coal lithotypes changing from dull coal, bright coal, semibright coal to semidull coal, the adsorption pores change from enclosed types to open, adsorption capacities improved in turn, which is favorable to adsorption, desorption and diffusion of coalbed methane. Seepage pores of bright coal are the most developed, semidull coal and semibright coal less, dull coal the least. The permeability of coal has a positive correlation between microfissure density and large pore content. Different macrolithotype of the same coal seam changes with the permeability could be divided into three stages, including fractures decrease rapidly stage, fractures decrease slowly stage and fractures tend to be closed stage.

A three-dimensional crystal plasticity (CP) finite element model is developed to reproduce the grain level stress concentration and deformation of polycrystalline aluminium alloy 7075 (AA7075) during fatigue experiments. The grains contained in the model possess the same size and crystallographic orientations obtained from electron back-scatter diffraction experiments. A modified CP constitutive model, which considers the backstress evolution, is employed to describe the mechanical behaviour of AA7075 under cyclic loading. A round-notched specimen from a fatigue test is simulated using the proposed CP model. Convergence studies in terms of mesh density and plastic deformation zone size are carried out to determine the appropriate conditions for the simulation. The simulation results are compared with those obtained using the elasto-plastic model and the CP model without grain morphology. The comparison indicates that with the embedded grain morphology, the proposed model can capture very well the local response induced by the microstructure features, which is vital to the accurate fatigue life prediction of aluminium alloys.

Iron oxide particles with spherical, date-pit like, or polyhedron morphology were obtained by hydrothermal method. The morphology, thermal analysis, crystal structure of the products was characterized by FESEM, thermogravimetry (TG), X-ray diffraction (XRD), respectively. The measured results reveal that the product of three different shapes is hematite (α-Fe2O3).

The recent dramatic progress in the printed electronics and flexible electronics, due to the universality of the substrates including the foldable and stretchable substrates, has opened a new prospect in the field of future electronics. In this paper, silver nanospheres in large-scale are synthesized, the nanosilver ink with 63.88% silver content are prepared and a new type of highly conductive and far identify distance RFID tags are manufactured. Especially there are no resin and other additives containing in our conductive ink which satisfy the rheological characteristics and process of screen printing. The tags exhibit the best radiation performance own to there is no high temperature sintering in need. The surface resistance of the tags could be 80 mΩ/, and the identify distance reach to 6.0m. Keywords:silver nanoparticles, conductive ink, RFID tags

The fact that it is difficult to establish the mathematical model of metal materials by theoretical study method means that can be done by statistical methods. Happens to, the logistic model is more suitable for this work. This paper tries to establish the model of steel hardenability curve by transforming logistic model without a large number of specimens.