Advanced Materials Research Vols. 455-456

Abstract: Shilu iron mine is an important iron mine in China, with deposits of 314 million tons and average ore grade of 51.15%, and is the biggest iron-rich deposit in Asia. Beiyi iron open-pit is the biggest open-pit of Shilu iron mine. The height of west wall of Beiyi open-pit is 400m, and the height will be 492m in 2013. Due to the effects of tectonic movements, the rock mass is fractured seriously, and more discontinuities paralleling the slope are unfavorable to slope stability. Since 1998, the deformation of slope is obvious, with horizontal displacement of about 2.9m and vertical displacement of about 1.5m. On the basis of in situ investigation and monitoring data, deformation mechanism of west wall of Beiyi open-pit is analyzed in detail. The results of this research are useful to the slope safety assessment and the following treatment design.

Abstract: In the Danchi mineralization belt of Guangxi province, south China, the Dachang tin-polymetallic ore deposit is one of the largest Sn ore deposits in this world. But about the genesis and the ore source, there have been some disputes. In terms of the Dafulou deposit, the mineralization model and deposit mechanism is rather illegibility. By analysing and comparing the lead isotope of three ore deposit (the Changpo, the Lamo and the Dafulou), it show that the correlations of 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb of sulfide minerals demonstrate obvious excellent linear relation. So, it is also suggested that the eastern mineralization belt, the middle mineralization belt and the western mineralization belt shared the same ore source. And, according to the features of no.22 ore body, the Dafulou deposit is characterized with the characteristics of the Sedimentary Exhalative Deposit (SEDEX).

Abstract: The safety study of transgenic plants has an actual significance for creating new species and commercializing transgenic plants. Based on PCR and Southern blotting tests of transgene, the genetic stability of ipt gene in an advanced-generation of transgenic rice plants was studied. Use a plate colony counting technique, the influence of ipt rice plants on bacteria number of rhizospheric soil was investigated. Molecular detection showed foreign ipt gene was stable genetic in the genome of T8 transgenic rice with a single copy. The amounts of bacteria from the root soil of transgenic lines were distinct from non-transgenic controls during the tillering stage, heading stage and filling stage. Nevertheless, this variability was not significant during the growing season described above (P>0.05). These results reveal that T8-ipt rice cannot affect the soil bacteria biomass during plants field-growth.

Abstract: In order to study the migration characters of organophosphorus in clay, experiment was designed to simulate the process of organophosphor leakage permeating the aquitard, searching the migration characters of organophosphorus in clay with different pH. It is shown that the ability of migration of organophosphor leakage permeating the cohesive soil fall with increase of pH between7.5 and 9.5, and the extent of mineralization for organophosphor in clay rise with increase of pH.

Abstract: Electromagnetic waves will be attenuation when through plasma because of absorption and refraction efferts. Active application of plasma attenuation effect has good application prospect, such as aircraft stealth. But at the same time, the attenuation effect oneself will also bring some problems. For exzample, as the power system of the spacecraft, electric thruster plasma jet is possiblly to cause some problem on the communication between spacecraft and ground stations [1] .

Abstract: Early age strength of ceramisite concrete gains quickly in strength,the 7d strength can be over 80% of the 28d strength.The thesis researched on relationship between age and strength with a great lot of experiments,and predicted the 28d strength by early age strength,that satisfied the project need.

Abstract: The paper analyzes the stress relaxation damage mechanisms of high temperature (HT) bolts of ultra-supercritical steam turbine units. Based on creep damage mechanisms and relaxation characteristics, the paper proposes a life prediction model, and by which to predict relaxation damage life of HT bolting material 1Cr10NiMoW2VNbN. Validation results indicate that the developed model has led to better consistent results with experimental data and thus can be recommended in relaxation life evaluation of HT materials.

Abstract: Stress relaxation constitutive equations based on Continuum Damage Mechanics, Kachanov-Robatnov creep model, and stress relaxation equation has been developed by analyzing stress relaxation damage mechanisms and considering the relationship that stress relaxation is creep at various stresses. And, the constitutive differential equations were integrated to predict stress relaxation performance by using numerical analysis technique. In order to validate the approach, the predicted results are compared to the experimental results of uni-axial isothermal stress relaxation tests conducted on 1Cr10NiMoW2VNbN steel with the same temperature of creep tests. Good agreement between results of relaxation tests and the predicted results indicates that the developed constitutive models can be used in the relaxation behavior evaluation of high temperature materials.

Abstract: Based on principle of vehicle-track-bridge dynamic interaction, a dynamic simulation model of a high-speed electric multiple units (EMUs) passing over turnout on bridge was established. The calculation focused on 200km/h No.12 improved ballasted turnout (60kg/m rail) being laid on 3×32.0m simply supported beam, it analyze dynamic characteristics of a freight train with 25t axle load passing at speed of 120km/h and those of CRH1 EMUs passing at speed of 200km/h. Results show that: when the freight train passes the turnout through the main line, the vertical stiffness of the simply supported beams is not sufficient due to the relatively high speed and large axle load; when the EMUs passes the turnout on bridge, the dynamic deflection change rates of girders at the switch and frog are great and the turnout is not appropriately set on the bridge, so the frog crosses over the beam gap, which results in the increasing of track irregularity and finally causes derailment coefficient of vehicle to overrun to reduce the running safety; when a train passes the turnout zone on bridge, interaction between the vehicle and turnout is significant because of load fluctuation of the wheel caused by inevitable structural irregularity at the switch and nose rail, and this requires strengthening measurement and running within speed limit.

Abstract: This paper is involved in triangulating surface of the hollow cylinder. The strategy is proposed for generating surface triangulation elements for the hollow cylinder at first. The strategy of adjusting the surface triangulation elements which are adjacent to the crossing cures in the hollow cylinder, is discussed. The computer implementation on the strategy proposed in this paper is given and the numerical example is performed. The example of the hollow cylinder verifies the correctness of the strategy proposed in this paper.