951 resultados para Parallel to grain


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The interactions of lanthanide ions and the Ln-DTPA (DTPA = diethylenetriaminepentaacetate) complex with di palmitoylphosphatidylcholine (DPPC) and dipalmitoylphosphatidylethanolamine (DPPE) bilayers are studied by 2D NOESY and FT-Raman spectroscopy. Proton NMR spectroscopic results show that lanthanide ions combine with phosphate groups in the polar region of the outer layer of DPPC liposomes, leading to the separation in chemical shift of the proton signal of N(CH3)(3) The conformational change of the O-C-C-N+ backbone from the gauche conformer to the trans one is not found; i.e., the orientation of the polar headgroup is still parallel to the surface of the bilayers. The Ln-DTPA complex at low concentration in a pH 7.4 solution localizes far away from bilayers and thereby has little effect on the structure of bilayers. The FT-Raman spectroscopic results indicate that lanthanide ions affect strongly the fluidity of acyl chains of DPPE bilayers while the Ln-DTPA complex affects it slightly.

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Epitaxial crystallization behavior of HDPE/iPP double layers under quenching and annealing conditions has been studied by means of transmission electron microscopy (TEM). The results obtained from bright field TEM observations indicate that in the as-quenched state the HDPE that is in direct contact with the surface of the oriented iPP substrate recrystallizes in the form of oriented crystallites dispersed on the iPP substrate. The electron diffraction results show that besides the two normally observed epitaxial orientations between HDPE and iPP, there is also a special orientation with [001](HDPE)parallel to[001](iPP). The HDPE which is in contact with the clean surface of a glass slide crystallizes in small lamellae with random orientation. In the boundary region, the epitaxially crystallized HDPE small lamellae stop right on the boundary of the oriented iPP film. If the quenched samples are annealed at 128 degrees C (below T-m of HDPE) for 2 h, the small HDPE crystals grow to thick lamellae in both areas. But only the epitaxial orientation of HDPE with [001](HDPE)parallel to[101](iPP) has been observed.

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The interactions of lanthanide ions with sphingomyelin bilayers have been studied by using 2D NOESY spectroscopy and FT-Raman spectroscopy methods. The results indicate that lanthanide ions, as well as divalent calcium, combine mainly to the phosphate group in the polar headgroup and do not change the conformation of O-C-C-N+ backbone in the choline group of sphingomyelin bilayers. The polar headgroup is still extending parallel to the bilayer surface and O-C-C-N+ group is still in its gauche conformer.

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SERRS of copper tetrakis(2,4-ditert-penthyl phenoxy) Phthalocyanine LB monolayer on Ag island film and RRS of the compound in solid state have been obtained. On comparison between the spectra, it is proposed that the macrocycle of the molecule on the Ag substrate is oriented parallel to the surface.

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Processing of a recently acquired seismic line in the northeastern South China Sea by Project 973 has been conducted to study the character and the distribution of gas hydrate Bottom-Simulating Reflectors (BSRs) in the Hengchun ridge. Analysis of different-type seismic profiles shows that the distribution of BSRs can be revealed to some extents by single-channel profile in this area, but seismic data processing plays an important role to resolve the full distribution of BSRs in this area. BSR' s in the northeastern South China Sea have the typical characteristics of BSRs on worldwide continental margins: they cross sediment bed reflections, they are generally parallel to the seafloor and the associated reflections have strong amplitude and a negative polarity. The characteristics of BSRs in this area are obvious and the BSRs indicate the occurrence of gas hydrate-bearing sediments in the northeastern South China Sea. The depth of the base of the gas-hydrate stability zone was calculated using the phase stability boundary curve of methane hydrate and gas hydrate with mixture gas composition and compared with the observed BSR depth. If a single gradient geothermal curve is used for the calculation, the base of the stability zone for methane hydrate or gas hydrate with a gas mixture composition does not correspond to the depth of the BSRs observed along the whole seismic profile. The geothermal gradient therefore changes significantly along the profile. The geothermal gradient and heat flow were estimated from the BSR data and the calculations show that the geothermal gradient and heat flow decrease from west to east, with the increase of the distance from the trench and the decrease of the distance to the island arc. The calculated 2 heat flow changes from 28 to 64 mW/m(2), which is basically consistent with the measured heat flow in southwestern offshore Taiwan.

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Magnetotactic bacteria (MTB) are ubiquitous in aquatic habitats. Because of their fastidious requirements for growth conditions, only very few axenic MTB cultures have been obtained worldwide. In this study, we report a novel marine magnetotactic spirillum axenic culture, designated as QH-2, isolated from the China Sea. It was able to grow in semi-solid or liquid chemically defined medium. The cells were amphitrichously flagellated and contained one single magnetosome chain with an average number of 16 magnetosomes per cell. Phosphate and lipid granules were also observed in the cells. Both rock magnetism and energy-dispersive X-ray spectroscopy characterizations indicated that the magnetosomes in QH-2 were single-domain magnetites (Fe3O4). QH-2 cells swam mostly in a straight line at a velocity of 20-50 mu m/s and occasionally changed to a helical motion. Unlike other magnetotactic spirilla. QH-2 cells responded to light illumination. As a consequence of illumination, the cells changed the direction in which they swam from parallel to the magnetic field to antiparallel. This response appears to be similar to the effect of an increase in [O-2]. Analysis of the QH-2 16S rRNA sequence showed that it had greater than 11% sequence divergence from freshwater magnetotactic spirilla. Thus, the marine QH-2 strain seems to be both phylogenetically and magnetotactically distinct from the freshwater Magnetospirillum spp. studied previously. (C) 2010 Elsevier Masson SAS. All rights reserved.

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In the title compound, [CdCl2(C13H12N2O)(2)], the Cd-II ion is situated on an inversion centre, coordinated by two 0 atoms [Cd-O=2.3878 (17) angstrom] and two N atoms [Cd-N = 2.3404 (15) angstrom] from two N-(2-pyridylmethyl)benzamide ligands, and two Cl atoms [Cd-Cl = 2.5566 (6) angstrom], in a distorted octahedral geometry. In the crystal structure, intermolecular N-H center dot center dot center dot Cl hydrogen bonds [N center dot center dot center dot Cl = 3.1705 (18) angstrom] and pi-pi interactions, with a distance of 3.868 (3) angstrom between the centroids of the phenyl and pyridyl rings of neighbouring molecules, lead to the formation of two-dimensional layers parallel to the bc plane.

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The title compound, [ CdCl2( C12H8N2)(2)]center dot 0.5H(2)O, crystallizes with two independent complex molecules and one water molecule in the asymmetric unit. The Cd atoms in both independent complexes display a distorted octahedral coordination geometry formed by four N atoms from two phenanthroline ligands and two Cl atoms. In the crystal structure, pi-pi stacking interactions link complexes in two symmetry- independent ladders parallel to the c axis. Intermolecular O-H center dot center dot center dot Cl hydrogen bonds stabilize the crystal packing.

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提出了一种新型的可重构蛇形机器人机构。该机构主要特点是单关节结构模块化 ,具有可适应地面形状变化的柔性连接环节和类似于蛇腹鳞摩擦特性的机构底部 ,手动可重构 ,当单自由度关节轴线互相平行连接时 ,该机构可实现多种平面运动形式 ,当单自由度关节轴线垂直依次连接时 ,形成的蛇形机器人具有两自由度的关节 ,可进行多种空间运动。试验结果证实 ,该蛇形机构重量轻、控制简单、运动灵活 ,能够很好地仿生蛇的多种运动形式

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In this dissertation, we investigated two types of traveling ionospheric disturbances (TIDs)/gravity waves (GWs) triggered separately by auroral energy input during super geomagnetic storms and solar terminator (ST) under quiet geomagnetic conditions (kp<3+) using TEC measurements from the global network of GPS receivers. Research into the generation and propagation of TIDs/GWs during storms greatly enhance our understandings on the evolution processes of energy transportation from the high-latitude’s magnetosphere to the low-latitude ionosphere and the conjugated effect of TIDs propagation between the northern and southern hemispheres. Our results revealed that the conjugacy of propagation direction between the northern and southern hemispheres was subject to the influence of Coriolis force. We also figure out the evolution processes of ionospheric disturbances at the global scale. These are important topics that had not been well addressed previously. In addition, we also obtained thee wave structures of medium scale TIDs excited by the solar terminator (ST) moving over the northern America and physical mechanisms involved. Our observations confirm that the ST is a stable and repetitive source of ionospheric wave disturbances and the evidence of solar terminator generated disturbances has been demonstrated experimentally via the GPS TEC measurement. The main researches and results of this dissertation are as follows. First, the global traveling ionospheric disturbances (TIDs) during the drastic magnetic storms of October 29–31, 2003 were analyzed using the Global Position System (GPS) total electron content (TEC) data observed in the Asian-Australian, European and North American sectors. We collected the most comprehensive set of the TEC data from more than 900 GPS stations on the International GNSS Services (IGS) website and introduce here a strategy that combines polynomial fitting and multi-channel maximum entropy spectral analysis to obtain TID parameters. Moreover, in collaboration with my thesis advisor, I have developed an imaging technique of 2-dimensional map of TIDs structures to obtain spatial and temporal maps of large scale traveling ionospheric disturbances (LSTIDs). The clear structures of TEC perturbations map during the passage of TIDs were displayed. The results of our study are summarized as follows: (1) Large-scale TIDs (LSTIDs) and medium-scale TIDs (MSTIDs) were detected in all three sectors after the sudden commencement (SC) of the magnetic storm, and their features showed longitudinal and latitudinal dependences. The duration of TIDs was longer at higher latitudes than at middle latitudes, with a maximum of about 16 h. The TEC variation amplitude of LSTIDs was larger in the North American sector than in the two other sectors. At the lower latitudes, the ionospheric perturbations were more complicated, and their duration and amplitude were relatively longer and larger. (2) The periods and phase speeds of TIDs were different in these three sectors. In Europe, the TIDs propagated southward; in North America and Asia, the TIDs propagated southwestward; in the near-equator region, the disturbances propagated with the azimuth (the angle of the propagation direction of the LSTIDs measured clockwise from due north with 0°) of 210° showing the influence of Coriolis force; in the Southern Hemisphere, the LSTIDs propagated conjugatedly northwestward. Both the southwestward and northeastward propagating LSTIDs are found in the equatorial region. These results mean that the Coriolis effect cannot be ignored for the wave propagation of LSTIDs and that the propagation direction is correlated with the polar magnetic activity. (3) The day (day of year: 301) before the SC (sudden commencement) of magnetic storm, we observed a sudden TEC skip disturbances (±10 TECU). It should be a response for the high flux of proton during the solar flare event, but not the magnetic storms. Next, the most comprehensive and dense GPS network’s data from North-America region were used in this paper to analyze the medium scale traveling ionospheric disturbances (MSTIDs) which were generated by the moving solar terminator during the quiet days in 2005. We applied the multi-channel maximum entropy spectral analysis to calculated TID parameters, and found that the occurrence of ST-MSTIDs depends on the seasonal variations. The results of our study are summarized as follows: (1) MSTIDs stimulated by the moving ST (ST-MSTIDs) are detected at mid-latitudes after the passage of the solar terminator with the life time of 2~3 hours and the variation amplitude of 0.2~0.8 TECU. Spectral analysis indicated that the horizontal wavelength, average period, horizontal phase velocity of the MSTIDs are around 300±150 km,150±80 m/s and 25±15 min, respectively. In addition, ST-MSTIDs have wave fronts elongating the moving ST direction and almost parallel to ST. (2) The statistical results demonstrate that the dusk MSTIDs stimulated by ST is more obvious than the dawn MSTIDs in summer. On the contrary, the more-pronounced dawn MSTIDs occurs in winter. (3) Further analysis indicates that the seasonal variations of ST-MSTIDs occurrence frequency are most probably related to the seasonal differences of the variations of EUV flux in the ionosphere region and recombination process during sunrise and sunset period at mid-latitudes. Statistical study of occurrence characteristics of TIDs using the GPS network in North-American and European during solar maximum, In conclusion, statistical studies of the propagation characteristics of TIDs, which excited by the two common origins including geomagnetic storms and moving solar terminator, were involved with global GPS TEC databasein this thesis. We employed the multichannel maximum entropy spectral analysis method to diagnose the characteristics of propagation and evolvement of ionospheric disturbances, also, the characteristics of their regional distribution and climatological variations were revealed by the statistic analysis. The results of these studies can improve our knowledge about the energy transfer in the solar-terrestrial system and the coupling process between upper and lower atmosphere (thermosphere-ionosphere-mesosphere). On the other hand, our results of the investigation on TIDs generated by particular linear origin such as ST are important for developing ionospheric irregularity physics and modeling the transionosphere radio wave propagation. Besides, the GPS TEC representation of the ST-generated ionospheric structure suggests a better possibility for investigating this phenomenon. Subsequently, there are scientific meaning of the result of this dissertation to deeply discuss the energy transfer and coupling in the ionosphere, as well as realistic value to space weather forecast in the ionosphere region.

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The Yaoyingtai Block is located within the northeastern Changling Depression of southern Songliao Basin, where the reservoir sandstones are petrophysically characterized by very low permeability, which results in the low success probability of artificial fracturing, and the low oil yield by water injection in the course of oil production. In order to improve the situations as stated above, this research aims to work out an integral fracturing technology and strategy applicable to the low permeable reservoirs in Yaoyingtai Block. Under the guidance of geological theory, reservoir engineering and technology, the subsurface occurrences of natural and hydraulic fractures in the reservoirs are expected to be delineated, and appropriate fracturing fluids and proppants are to be optimized, based on the data of drilling, well logging, laboratory and field experiments, and geological data. These approaches lay the basis of the integral fracturing technology suitable for the low permeable reservoir in the study area. Based on core sample test, in-situ stress analysis of well logging, and forward and inversion stress field modeling, as well as fluid dynamic analysis, the maximum in-situ stress field is unraveled to be extended nearly along the E-W direction (clustering along N85-135°E) as is demonstrated by the E-W trending tensional fractures. Hydraulic fractures are distributed approximately along the E-W direction as well. Faulting activities could have exerted obvious influences on the distribution of fractures, which were preferentially developed along fault zones. Based on reservoir sensitivity analysis, integrated with studies on rock mechanics, in-situ stress, natural fracture distribution and production in injection-production pilot area, the influences of primary fractures on fracturing operation are analyzed, and a diagnostic technology for primary fractures during depressurization is accordingly developed. An appropriate fracturing fluid (hydroxypropyl guar gum) and a proppant (Yixing ceramsite, with a moderate-density, 0.45-0.9mm in size) applicable to Qingshankou Formation reservoir are worked out through extensive optimization analysis. The fracturing fluid can decrease the damage to the oil reservoir, and the friction in fracturing operation, improving the effect of fracturing operation. Some problems, such as sand-out at early stage and low success rate of fracturing operations, have been effectively solved, through pre-fracturing formation evaluation, “suspension plug” fracturing, real-time monitoring and limited-flow fracturing. Through analysis of fracture-bearing tight reservoir with variable densities and dynamic analysis of influences of well patterns on fracturing by using numerical simulation, a fracturing operation scheme for the Qingshankou Formation reservoir is proposed here as being better to compress the short factures, rather than to compress the long fractures during hydraulic fracturing. It is suggested to adopt the 450m×150m inverted 9-spot well pattern in a diamond shape with wells placed parallel to fractures and a half fracture length of 60-75m.

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There has been a growing concern about the use of fossil fuels and its adverse effects on the atmospheric greenhouse and ecological environment. A reduction in the release rate of CO2 into the atmosphere poses a major challenge to the land ecology of China. The most promising way of achieving CO2 reduction is to dispose of CO2 in deep saline aquifers. Deep aquifers have a large potential for CO2 sequestration in geological medium in terms of volume and duration. Through the numerical simulation of multiphase flow in a porous media, the transformation and motion of CO2 in saline aquifers has been implemented under various temperature and hydrostatic pressure conditions, which plays an important role to the assessment of the reliability and safety of CO2 geological storage. As expected, the calculated results can provide meaningful and scientific information for management purposes. The key problem to the numerical simulation of multiphase flow in a porous media is to accurately capture the mass interface and to deal with the geological heterogeneity. In this study, the updated CE/SE (Space and time conservation element and solution element) method has been proposed, and the Hybrid Particle Level Set method (HPLS) has extended for multiphase flows in porous medium, which can accurately trace the transformation of the mass interface. The benchmark problems have been applied to evaluate and validate the proposed method. In this study, the reliability of CO2 storage in saline aquifers in Daqingzi oil field in Sunlong basin has been discussed. The simulation code developed in this study takes into account the state for CO2 covering the triple point temperature and pressure to the supercritical region. The geological heterogeneity has been implemented, using the well known geostatistical model (GSLIB) on the base of the hard data. The 2D and 3D model have been set up to simulate the CO2 multiphase flow in the porous saline aquifer, applying the CE/SE method and the HPLS method .The main contents and results are summarized as followings. (1) The 2D CE/SE method with first and second –order accuracy has been extended to simulate the multiphase flow in porous medium, which takes into account the contribution of source and sink in the momentum equation. The 3D CE/SE method with the first accuracy has been deduced. The accuracy and efficiency of the proposed CE/SE method have been investigated, using the benchmark problems. (2) The hybrid particle level set method has been made appropriate and extended for capturing the mass interface of multiphase flows in porous media, and the numerical method for level set function calculated has been formulated. (3) The closed equations for multiphase flow in porous medium has been developed, adept to both the Darcy flow and non-Darcy flow, getting over the limitation of Reynolds number to the calculation. It is found that Darcy number has a decisive influence on pressure as well as velocity given the Darcy number. (4) The new Euler scheme for numerical simulations of multiphase flows in porous medium has been proposed, which is efficient and can accurately capture the mass interface. The artificial compressibility method has been used to couple the velocities and pressure. It is found that the Darcy number has determinant effects on the numerical convergence and stability. In terms of the different Darcy numbers, the coefficient of artificial compressibility and the time step have been obtained. (5) The time scale of the critical instability for critical CO2 in the saline aquifer has been found, which is comparable with that of completely CO2 dissolved saline aquifer. (6) The concept model for CO2 multiphase flows in the saline aquifer has been configured, based on the temperature, pressure, porosity as well as permeability of the field site .Numerical simulation of CO2 hydrodynamic trapping in saline aquifers has been performed, applying the proposed CE/SE method. The state for CO2 has been employed to take into account realistic reservoir conditions for CO2 geological sequestration. The geological heterogeneity has been sufficiently treated , using the geostatistical model. (7) It is found that the Rayleigh-Taylor instability phenomenon, which is associated with the penetration of saline fluid into CO2 fluid in the direction of gravity, has been observed in CO2 multiphase flows in the saline aquifer. Development of a mushroom-type spike is a strong indication of the formation of Kelvin-Helmholtz instability due to the developed short wavelength perturbations present along the interface and parallel to the bulk flow. Additional key findings: the geological heterogeneity can distort the flow convection. The ascending of CO2 can induce the persistent flow cycling effects. The results show that boundary conditions of the field site have determinant effects on the transformation and motion of CO2 in saline aquifers. It is confirmed that the proposed method and numerical model has the reliability to simulate the process of the hydrodynamic trapping, which is the controlling mechanism for the initial period of CO2 storage at time scale of 100 years.

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As a marginal subject, dynamic responses of slopes is not only an important problem of engineering geology (Geotechnical problem), but also of other subjects such as seismology, geophysics, seismic engineering and engineering seismic and so on. Owning to the gulf between different subjects, it is arduous to study dynamic responses of slopes and the study is far from ripeness. Studying on the dynamic responses of slopes is very important in theories as well as practices. Supported by hundreds of bibliographies, this paper systemically details the development process of this subject, introduces main means to analyze this subject, and then gives brief remarks to each means respectively. Engineering geology qualitative analysis is the base of slopes dynamic responses study. Because of complexity of geological conditions, engineering geology qualitative analysis is very important in slopes stability study, especially to rock slopes with complex engineering geology conditions. Based on research fruits of forerunners, this paper summarizes factors influencing slopes dynamic stability into five aspects as geology background, stratums, rock mass structure, and topography as well as hydrogeology condition. Based on rock mass structure controlling theory, engineering geology model of the slope is grouped into two typical classes, one is model with obvious controlling discontinuities, which includes horizontal bedded slope, bedding slope, anti-dip slope, slide as well as slope with base rock and weathered crust; the other is model without obvious controlling discontinuities, which includes homogeneous soil slope, joint rock mass slope. Study on slope failure mechanism under dynamic force, the paper concludes that there are two effects will appear in slope during strong earthquake, one is earthquake inertia force, the other is ultra pore pressure buildup. The two effects lead to failure of the slope. To different types of slope failure, the intensity of two effects acting on the slope is different too. To plastic flow failure, pore pressure buildup is dominant; to falling rock failure and toppling failure, earthquake inertia force is dominant in general. This paper briefly introduces the principle of Lagrangian element method. Through a lot of numerical simulations with FLAC3D, the paper comprehensively studies dynamic responses of slopes, and finds that: if the slope is low, displacement, velocity and acceleration are linear enlarging with elevation increasing in vertical direction; if the slope is high enough, displacement, velocity and acceleration are not linear with elevation any more, on the other hand, they fluctuate with certain rhythm. At the same time, the rhythm appears in the horizontal direction in the certain area near surface of the slope. The distribution form of isoline of displacement, velocity and acceleration in the section of the slope is remarkably affected by the slope angle. In the certain area near the slope surface, isoline of displacement, velocity and acceleration is parallel to the surface of the slope, in the mean time, the strike direction of the extreraum area is parallel to the surface of the slope too. Beyond this area, the isoline direction and the strike direction of the extremum area turn to horizontal with invariable distance. But the rhythm appearing or not has nothing to with the slope angle. The paper defines the high slope effect and the low slope effect of slopes dynamic responses, discusses the threshold height H^t of the dynamic high slope effect, and finds that AW is proportional to square root of the dynamic elastic moduli El P , at the same time, it is proportional to period Tof the dynamic input. Thus, the discriminant of H^t is achieved. The discriminant can tell us that to a slope, if its height is larger than one fifth of the wavelength, its response regular will be the dynamic high slope effect; on the other hand, its response regular will be the dynamic low slope effect. Based on these, the discriminant of different slopes taking on same response under the same dynamic input is put forward in this paper. At the same time, the paper studies distribution law of the rhythm extremum point of displacement, velocity and acceleration, and finds that there exists relationship of N = int among the slope height H, the number of the rhythm extremum VHlhro) point N and ffthre- Furthermore, the paper points out that if N^l, the response of the slope will be dynamic high slope effect; \fNto //,/,",. At the same time, the paper finds that the distance of two adjacent extremum districts near the slope surface is H,hn too. In chaptet 5, based on residual pushing force model as well as pore pressure model of Martin-Finn-Seed, a method for estimating the permanent displacement of the slide is put forward in this paper, and then put it into dynamic analysis of the left abutment slope of Jinping hydropower station. The forecasting result is almost coincided with numerical simulation result. The Jinping hydropower station, located at the middle stream of Yalongjiang River and the west side of Jinpingdahewan, is the highest double-curvature arch dam planned in building in the world. However, deep fractures are well developed at the left abutment slope, so stability of the slope is a key engineering geological problem. The paper studies the dynamic stability of the slope. In the analysis, considering regional geology and regional seismology of the slope, combining with characteristics of the slope as well as the scale of the project, PGA(peak ground acceleration) of the site is decided (about 197.1cm/s2) by engineering seismology, and then the seismic input used in the slope dynamic analysis is determined. Comprehensive studies are carried out on the slope, especially to its deep fractures, and then the paper concludes that the deep fractures of slope are the result of the combination unloading effect of gravity and tectonic stress. At the same time, the failure model of the slope under dynamic input is attained. Based on these, the stability is comprehensively studied for section IV-IV with numerical simulation method as well as method putting forward in chapter 5. At last, the paper concludes that under dynamic input, the section will slide along fault f9, some deep fractures and fault/5 with certain permanent displacement, and this must be taken into consideration in the engineering.

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Anduo area is located in the Central Tibet, the middle segment of the Bangonghu-Nujiang suture. Anduo Block is the northern part of Lhasa terrane. The relationships among the different geological bodies were determined during the 1: 250000 regional geological surveying. Petrography, petrologic geochemistry, isotopic geochemistry and geochronology of igneous rocks from the suture and granitoids from Anduo Block were analyzed systematically as a whole for the first time. Then, their tectonic setting and history are discussed.Anduo ophiolitic melange consists of metamorphic peridotites, cumulates, plagiogranites, sheeted dykes swarm, pillow lava and radiolarian cherts. The concentration of Cr and Ni in the metamorphic peridotites is very high, with Mg# about 0.94 ~ 0.97, higher 87Sr/86Sr and Pb isotopic ratios, and lower 143Nd/i44Nd ratio. LREE is enriched relative to HREE and positive Eu anomaly is very clear. The REE distribution curve is U shape. Nb and Ta anomalies from cumulate gabbro and sheeted dyke swarm are not clear, while that are slightly negative from pillow lava. Plagiogranite belongs to strong calc-alkaline series with high Si, middle Al, low Fe, Mg and low K contents. Eu anomaly (~ 1.23) from plagiogranites is slightly positive. The character of all components of ophiolite is similar to that of the MORB, while to some extent the ophiolite was influenced by crustal material. Anduo ophiolite formed in a mature back-arc basin. Additionally, intermediate acidity volcanic rocks within Anduo phiolite melange are island arc calc-alkline rocks related to ocean subduction.The early-middle Jurassic plutonic rocks are tonalite, granodiorite bearing-phenocryst, magaporphyritic hornblende monzogranite, magaporphyritic monzogranite, monzogranite bearing-phenocryst and syenogranite in turn. They belong to calc-alkaline series which developed from middle K to high K series temporally. REE distribution curves of all plutonic rocks are similar and parallel to each other. SREE and negative Eu anomaly values decrease. In the multi-element spider diagram, the curves of different plutons are similar to each other, but troughs of Nb, Sr, P and Ti from young plutons become more evident. This suggests that thereare some closely petrogenetic affinities among plutonic rocks which make up amagma plutonism cycle of the early-middle Jurassic. Magma source is mainly crustal,but abundant mafic microgranular enclaves within granitoids indicate that crastalmagma should be mixed with mantle-derived magma and the mantle-derived magmadecreased subsequently. Tonalite has features of I-type granite, magaporphyriticmonzogranite is transition type, and monzogranite bearing-phenocryst is S-typegranite. The characteristic of granitoids from Anduo Block suggest that the formingtectonic setting is active continental margin.Reliable zircon U-Pb SHRIMP ages are obtained in the study area firstly. Plagiogranite from the Anduo ophiolite of the Bangonghu-Nujiang suture is 175.1 Ma, and granitoids from Anduo Block is 172.6-185.4 Ma. Additionally, plagioclase from the plagiogranite dates a 40Ar/39Ar age of 144 Ma, while biotite and hornblend from granitoids of Anduo Block give a 163-165 Ma.Similar cooling ages of plagiogranite from the Anduo ophiolitic melange and granitoids from Anduo Block and the spatial distribution of the ophiolitic rocks between Anduo, Naqu, and Shainzha area suggest that bilateral subduction of the Bangonghu-Nujiang oceanic basin took place in the early-middle Jurassic. During this subduction, Anduo ophiolitic rocks were related to north subduction of the Bangonghu-Nujiang oceanic basin and Anduo back-arc basin spreading, while granitoids from Anduo Block were related to south subduction.

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Six experiments tested how headings of objects in scenes influenced the construction for the intrinsic frame of reference under different structure and viewpoint amount conditions. In Experiment 1 and 2, participants stood at 0 degree and learned an asymmetrical scene and a symmetrical scene that were composed by balls with no apparent headings separately. In Experiment 3, 4, 5 and 6, toys with apparent headings were used and they all faced the 315 degree of the scene. In Experiment 3 and 4, participants stood at 0 degree and learned an asymmetrical scene and a symmetrical scene that were composed by toys separately. In Experiment 5 and 6, participants stood at 0 and 315 degree and learned an asymmetrical scene and a symmetrical scene that were composed by toys separately. After learning, participants needed to finish triplet recognition tasks in all the experiments. The dependent measures were response latency and accuracy. The correct response latencies to the targets were analyzed by ANOVA. Accuracy was used to filter data and analyzed in an ANOVA in some experiments as a reference. Results indicate that headings of objects in scenes influence the pattern for intrinsic frame of reference. The structure of scene affects the acting mechanism of heading, but the amount of viewpoints does not have this effect. If the objects in scenes have no apparent headings, there will be viewpoint dependent effect and the advantage of symmetry axis as intrinsic axis in triplet recognition tasks. If the objects in scenes have apparent headings, people’s spatial memory pattern will be affected by objects’ headings. If the heading of objects (315 degree) is not parallel to the viewpoint (0 degree) in an asymmetrical scene, people will be inclined to represent the scene from the heading of objects but not from the viewpoint. As a result, the viewpoint dependent effect will disappear, and there is significant advantage for the triplets presented from heading of objects. If the heading of objects is not parallel to the symmetry axis in a symmetrical scene, people will represent the scene not only according to the symmetry axis as intrinsic axis, but also according to the heading of objects. As a result, the significant advantage for symmetry axis as intrinsic axis in triplet recognition tasks will disappear but there will be still a tendency. By contrast, the effect for the headings of objects is more significant in asymmetrical scenes than that in symmetrical scenes.