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The uniaxial and multiaxial non-proportional cyclic experiments of 16Mn steel under strain-control were carried out using MTS809 machine and Teststar control system. Cyclic softening was observed for 16Mn steel under strain-control cyclic loading. The restraining effects of mean strain, strain amplitude, non-proportional loading path and their histories to subsequent cyclic softening were revealed, and some useful conclusions for establishing constitutive model of non-proportional cyclic were obtained.

Visual stimulator is one of the key factors that affect the steady-state visual evoked potential (SSVEP). Research and development of brain-computer interface (BCI) system based on SSVEP have priority to consider the design and implementation of visual stimulation. Compare with visual stimulators for particular applications, this paper presents a visual stimulator that is portable and easy to modify apparatus, which is suitable for expanding the application of SSVEP based BCI system. This article induces a visual stimulator based on ARM microcontroller for BCI. The stimulator uses a common USB interface, achieving multiple selective stimulus methods. The system features include visual stimulation, parameter setting and display, the experimental results feedback display. Experimental data prove that this stimulator can be used for almost all types of brain-computer interface based on visual stimulation experiments, and have a portable operating mode, flexible parameter settings , and easy operation.

In this paper, the W-Al2O3 solar energy selective absorbing coating was prepared by magnetron sputtering. The selective absorption coating layers were obtained by setting different tungsten target sputtering power and sputtering time. The process parameters of magnetron sputtering were presented by comparing the selective absorption coating layers absorptivity and reflectivity.

The solar selective absorbing coating is the key component of solar energy collector which determines the heat conversion efficiency. The coating materials mentioned in this paper were prepared by Al as substrate, Al2O3-Pt as absorbing layer and metal Ag as infrared reflector. We got three kinds of coatings by adjusting the magnetron sputtering process. Respectively testing and analyzing the performance and microstructure showed that element content of Al, N, O in the coating are of important influence on its performance, meanwhile, the better the crystallization of coatings surface, the more helpful to improve the performance of its corrosion resistance and its moisture and heat resistance.

Coffee carbon fiber is a kind of functional polyester fiber. Waste coffee grounds is milled into nanometer powder and then added to the polyester spinning fluid. Coffee carbon filament yarns have the functions of antibacterial deodorant, sending anion, and thermal insulation. In this paper, the morphology and properties of coffee carbon filament yarns were tested, such as scanning electron microscopy, tensile, moisture regain and cohesion. Polyethylene terephthalate filament yarns were selected for comparison with coffee carbon yarns. The results show that coffee carbon powder is distributed both on the surface and inside of filament yarns; the moisture regain of coffee carbon filament yarns is higher than that of PET yarns; the strength and elongation of coffee carbon filament yarns and of PET filament yarns is close; the boiling water shrinkage of coffee carbon filament yarns is lower than that of PET filament yarns; the addition of carbon powder can not reduce the cohesion of coffee carbon filament yarns.

Porous hollow hydroxyapatite (HA) microspheres were synthesized by Chemical Precipitation process using Ca (NO3)2·4H2O and (NH4)3PO4·3H2O as reagents and the CAPB as organic template. With increasing the amount of CAPB, the morphology of HA varies from irregular floccule to the rod form the spherical prototype and then grow into porous hollow microspheres. Furthermore, the possible formation mechanism of morphology change is also discussed.

The design and measurement of Verdet constant of magneto optical fiber is reported. An optical beam was found that it linearly polarized at the fiber input changes to elliptically polarized after propagating down the fiber and an elliptical fitting method was studied and reported. Traditional method is based on circle polarized principle, rotation angle is obtained through manually adjust the polarizer which is rather inaccurate especially for small rotations. Through the development of elliptical fitting equations and the test of intensity on major and minor points, fiber Verdet constant can be measured more precisely. The measured data of TZN (TeO2- ZnO-Na2CO3) fiber was verified and it provides improved accuracy compared with existing methods.

The effect of tartaric acid on the electrochemical behavior of K3[Fe(CN)6] was investigated on bare ITO electrodes, electrodes coated with multi-walled carbon nanotubes possessing carboxyl groups (MWNT-COOHs), and electrodes coated with cyclodextrin modified multi-walled carbon nanotubes (MWNT-CDs), respectively. It is found that the molecular chirality of tartaric acid can hardly influence the electrochemical behavior of K3[Fe(CN)6] on bare ITO electrodes. When the electrodes coated with MWNT-COOHs are used, the effect of the molecular chirality becomes distinguish. In the case of the electrodes coated with MWNT-CDs, the enhanced chiral discrimination between D-tartaric acid (D-TA) and L-tartaric acid (L-TA) can be observed. The control step in the electrochemical reaction of K3[Fe(CN)6] on the electrodes coated with MWNT-CDs is deduced to be different when D-TA or L-TA is introduced into the solution, respectively. Therefore, the enhanced chiral discrimination on the electrodes coated with MWNT-CDs is probably due to the change of the control step in the electrochemical reaction of K3[Fe(CN)6] caused by the chiral recognition of cyclodextrin moieties to D-TA and L-TA.

This article establishes analysis model based on Multiple Nonlinear Regression and analyses the model using SPSS. Then eight indexes such as storage of Material sources are selected as independent variable, and make an empirical analysis by survey data of 40 debris flow valleys. Finally, the test results show that both the importance analysis of the impact factors of debris flow and the rank deviation of risk assessment are right. Moreover, using multiple nonlinear Regression model and SPSS to assess the risk of debris flow is proved feasible.

The Three-dimensional engineering geology data warehouse is constructed by Power Desinger16.1, with the theme as the rock and mass availability in urban underground space, and with the source data as the borehole data of engineering Investigation. Use the Model-driven Architecture method, reverse engineer the Access data base, extract existed data model, combine research theme to construct the Star data structure model. And check the SQL script in SQL Server2005, to ensure normal operation. 0 Forewords The traditional transaction-oriented designed engineering geology data base has the function to storage original data from work, to draw of geological section and to provide simple check and analysis, but without the decision support function in view of a subject. The purpose of construction a 3D engineering geological data warehouse is to build a decision support system in view of availability of rock and soil mass in urban underground space. Based on the data extraction, data integration, data cleaning and data transformation, the 3D engineering geological data warehouse could achieve the integrated management of massive geological data and to provide reliable data source for the rock and soil mass utilization system in urban underground space. The main feature of 3D engineering geological data base is subject-oriented, integrated, time-varying, relatively stable, and is magnanimous collection of engineering geological spatial data and attribute data. According to the design pattern of traditional data base, the construction of 3D engineering geological data warehouse can be divided into three stages: concept design model, logic design model and physical design model. But the 3D engineering geological data warehouse exist iterative in the construction process. Currently, there are many CASE tools to help developers quickly achieving the data base design, such as Rational Rose by Rational company, Erwin and Bpwin by CA company, Power Designer by Sybase company, Office Visio by Microsoft company, and Oracle Designer by Oracle company. The paper uses the Powerdesigner16.1 to achieve the logical data model (LDM) and physical data model (PDM).

Based on the remaining research results of database and its development software, this article develops the database system of geotechnical engineering exploration for a city using the database management system SQL Server 2005 and vb6.0, and establishes the database tables at all levels, and then advances the more reasonable System Structure, which make the system realize data edition function, information inquiry function, database management function, graph drawing function, data output function and so on. Moreover, the system interface is friendly and the system is easy to operate so that it is convenient for users to study and use, and it achieves good results.

Flower-cluster-like hydroxyapatite (HA) microspheres were synthesized through biomimetic method using Ca(NO3)2∙4H2O and (NH4)3PO4∙3H2O as reagents and N-Dodecyl-N, N-dimethyl-3-ammonio-1-propanesulfonate(DDAPS) as template. With increasing the amount of DDAPS, the morphology of HA varies from irregular floccule-like to long-rod-like, then growth into flower cluster microspheres. The possible formation mechanism of morphology change is also discussed.

Two key products were isolated and purified from liquid mixture composition of wheat straw, by means of a combination of organic solvent extraction and column chromatography. Their structures were identified on basis of nuclear magnetic resonance (1H-NMR, 13C-NMR, DEPT), mass spectrometry (MS), and infrared (IR). The mechanism of liquefaction of straw was inferred from the structures of products and changes of hydroxyl value and liquefaction residue, which make up the lack of mechanistic studies of overall utilization of plant fibers.

An optical-electronic system for Faraday rotation measurement is designed and constructed to evaluate the verdet constant of magnetic -optical glasses. The works include the optical bench setup and development of software. PbO-Bi2O3-B2O3 glasses systems were fabricated and characterized by using the self-constructed optical bench and the obtained Verdet constants @632.8nm for glass PBB1 was verified by using a commercial powermeter (as detector). The developed measurement system showed characteristics of low cost, small size and accurate.

As the performance of the wireless sensor networks is sensitive to the environment of the application, the analysis of wireless channel is carried out in the workshop of the chemical water treatment in power plant. With the power of noise and received signals sampled, the path-loss exponent γ is derived to establish the model of the wireless channel. To meet the requirement of the performance of wireless communication, such as a given bit error rate (BER), the upper bound of the distance between transmitter and receiver is also presented. At last, the conclusion is given.

The title compound (C7H9ClN2, Mr = 156.61), an imidazolium ionic liquid with alkynyl, was synthesized by an improved method in high yield. FT-IR,1H NMR,13C NMR and elemental analysis were performed to characterize the molecule of the ionic liquid, and its crystal structure was determined by single-crystal X-ray structure analysis. The results indicate that the improved procedure is very feasible and 96% yield. The crystal structure analysis will be conducive to clarify the relationship of structure and function for ionic liquid with alkynyl the compound.

Comparson research as to the relationship between building residues solidified by cement and those solidified by soil stabilizer are made , and the unconfined compressive strength of them increased over time are analyzed in the paper. When the soil stabilizer is mixed with the building residues, the acicular ettringites acting as inlay or infilling are formed in the solidified body. This is the reason why their unconfined compressive strength are increased. Some relevances show that the more the acicular ettringite was formed, the higher the confined compressive strength of the solidified bodies would be, and vice versa.

Forest management is the core task of the forestry development which urgently needs the support of Geography Information System (GIS) technology in the new century. With the development of GIS major, it is necessary to introduce GIS in the forest management discipline. We drew up the training objectives and main contents on GIS, based on the characteristics in the forest management discipline. In the end, we trained many students in the GIS major for the better development of forestry.

A general analysis method of curved bridge, pure twist theory, which is based on the bar structure mechanical, has been introduced in this paper, by analyzing the basic assumptions of the theory, the limitations of application of the theory is indicated, while the ratio between the width and span of the curved bridge is out of the rang prescribed in the theory. The prestress effect is studied by the method of numerical simulation based on the finite element software ANSYS . According to the result, it can be indicated that, under the prestress, a horizontal and vertical displacement of the curved beam have occurred. The whole beam appears the tendency of turning outside, and there has been wavy distortion in the outer cantilever slab of the box girder along the span. The analysis result shows that, the method of the force analysis of spatial entities should be adopted when the ratio of width/span is small, and the difference between the inner vertical resistant reaction and the outer one caused by the prestressing force should not be ignored.

Bio-degradable polyurethane foams were prepared from the liquefied wheat straw alcohol by a reaction with isocyanate in the presence of stannous octoate, triethylene diamine and silicone oil. The influences of the catalyst, water, silicone oil, isocyanate index(IN) on the performance of the properties of the foams obtained were investigated. Furthermore, the chemical structures, thermal performance and degradation performance of the products were analyzed.

This paper presents the test of ultrasonic impact for reducing the welding residual stress. Three full-scale specimens according to the anchor connection plate of main girder with cable of the Jiangjin Yangtze River Bridge are made and the ultrasonic impact test are taken in laboratory to study the effectiveness of reducing welding residual stress. The comparison of welding residual stress before ultrasonic impact with the stress after ultrasonic impact is conducted and the results from test show that the welding residual stress can significantly be reduced over 50% by ultrasonic impact method and even some stress in weld could be changed form tensile stress into compressive stress after ultrasonic impact.

Fe3O4 nanoparticles doped magnetic-optical PbO-Bi2O3-B2O3 glasses were prepared and studied and the effects of Fe3O4 nanoparticle on the properties of magnetic-optical glass were analyzed. It is found that the doping of Fe3O4 nanoparticles into glasses increased the Verdet constant of magneto optical glass without evident degradation in glass transmittance. The formation of Fe3O4 nanoparticles was obtained through coprecipitation of Fe(II) and Fe(III) in alkaline media. The structure and properties of doped glasses were studied by X-ray diffraction (XRD), scanning electric microscope (SEM), UV-VIS spectray analysis and Faraday rotation test etc.

The unearthed textile is an important material for human existence. This paper describes the design processing of database system of unearthed textiles. The database is built under the Microsoft Office Access, which mainly contains the age of unearthed textiles, category, excavated site, collection information, character description of textiles, picture, and literature sources. The function of this database includes data input, data maintenance, data query, data mining and data application.