岩石变形中三种方式的外力

外力是由外部施加于物体上的作用力,由点向外不断发出的力组成一束力,称为线状力;由一束束线状力集中成面状作用力,称为面状力;再由一个个面状力集中成较大规模的力,称为体状力。在中深变质岩区线状力形成L构造岩,面状力形成S构造岩,体状力形成大型的杆状构造和窗棱构造等。力是通过波的方式进行传导的,波分纵波和横波。纵波传播时,岩石的密度会加密和变疏,体积的大小发生变化,这样就有空间利于矿物生长和滑移。

0D-1D coupling model and 3D fluid-structure interaction model based on coronary CT angiography for displaying hemodynamic characteristics of coronary artery stenosis

Objective To observe value of 0D-1D coupling model and 3D fluid-structure interaction(FSI)model based on coronary CT angiography(CCTA)for displaying hemodynamic characteristics of coronary artery stenosis.Methods Based on CCTA data of the stenosed left anterior descending branch(LAD)in a patient with coronary heart disease,an 0D-1D coupling model and 3D FSI model were built,respectively.Then hemodynamic characteristic indexes,including the pressure,flow velocity and wall shear stress(WSS)were obtained in every 0.01 s during 1 s at 5 sampling points(i.e.sampling point 1—5)using these 2 models,respectively,and the consistencies of the results between models were evaluated with Spearman correlation coefficient r s.Results The time consuming for construction of 0D-1D coupling model and 3D FSI model was 0.033 min and 704 min,respectively.Both models showed basically distribution of the pressure,flow velocity and WSS of the stenosed LAD.For more details,the pressure at the stenosed segment of LAD and the proximal segment of stenosis were both higher,which gradually decreased at the distal segment of stenosis,and the flow velocity at the proximal segment of stenosis was in a relatively slow and uniform condition,with significantly increased flow velocity and WSS at the stenosed segment.Compared with 3D FSI model,0D-1D vascular coupling model was relatively unrefined and lack of distal flow lines when displaying blood flow velocity.For sampling point 2 at the stenosed segment of LAD,no significant consistency for pressure between 2 models was found(P=0.118),but strong consistency for the flow velocity and WSS(r s=0.730,0.807,both P<0.05).The consistencies of pressure,flow velocity and WSS between 2 models at the proximal and distal segment of stenosis,i.e.1,3—5 sampling points were week to moderate(r s=0.237—0.669,all P<0.05).Conclusion 0D-1D coupling model exhibited outstanding computational efficiency and might provide relatively reasonable results,while 3D FSI model showed higher accuracy for details and streamline when simulating LAD stenosis.

First-principles thermodynamics of metal-oxide surfaces andinterfaces:A case study review

An important step for achieving the knowledge-based design freedom on nano-and interfacial materials is attained by elucidating the related surface and interface thermodynamics from the first principles so as to allow engineering the microstructures for desired properties through smartly designing fabrication processing parameters.This is demonstrated for SnO2 nano-particle surfaces and also a technologically important Ag-SnO2 interface fabricated by in-situ internal oxidation.Based on defect thermodynamics,we first modeled and calculated the equilibrium surface and interface structures,and as well corresponding properties,as a function of the ambient temperature and oxygen partial pressure.A series of first principles energetics calculations were then performed to construct the equilibrium surface and interface phase diagrams,to describe the environment dependence of the microstructures and properties of the surfaces and interfaces during fabrication and service conditions.The use and potential application of these phase diagrams as a process design tool were suggested and discussed.

Genetic Analysis on Agronomic Traits of Doubled Haploid Population in Tobacco

[Objective] This study aimed to conduct genetic analysis on agronomic traits of doubled haploid population in tobacco. [Method] Main agronomic traits of DH population in tobacco were investigated, including plant height, effective number of leaves, lumbar leaf length, lumbar leaf width, intermodal distance and pericaulome length. Based on the estimation of skewness coefficient and kurtosis coefficient of Hongda x Hicks Broad Leaf populations, the number of gene pairs was calculated. [Result] The number of gene pairs controlling plant height （topping plant height and natural plant height） is 10.20 and 10.80, respectively; the number of gene pairs con- trolling leaf number （effective number of leaves and natural number of leaves） is 6.21 and 6.25, respectively; the number of gene pairs controlling pericaulome length, intermodal distance, lumbar leaf length and lumbar leaf width is 8.51, 15.30, 20.36 and 17.45, respectively. [Conclusion] This study revealed the characteristics of genetic variation of tobacco traits, which provided theoretical basis for the breeding of new varieties.

Influence of bluff body shape on wall pressure distribution in vortex flowmeter

To investigate the influence of bluff body shape on wall pressure distribution in a vortex flowmeter,experiments were conducted on a specially designed test section in a closed water rig at Reynolds numbers of 6.2×10 4-9.3×10 4.The cross sections of the bluff bodies were semicircular,square,and triangular shaped,and there were totally 21 pressure tappings along the conduit to acquire the wall pressures.It is found that the variation trends of wall pressures are basically identical regardless of the bluff body shapes.The wall pressures begin to diverge from 0.3D(D is the inner diameter of the vortex flowmeter) in front of the bluff body due to the diversity in shape,and all reach the minimum values at 0.3D behind the bluff body.A discrepancy between the triangular or square cylinder and the semicircular cylinder in wall pressure change is observed at 0-0.1D behind the bluff body.It is also found that the wall pressures and irrecoverable pressure loss coefficients increase with flow rates,and the triangular cylinder causes the smallest irrecoverable pressure loss at a fixed flow rate.

Study on law of raw coal seepage during loading process at different gas pressures

In order to reveal the law of raw coal seepage at different gas pressures, the gravity constant load seepage experimental system was developed and used. The law of raw coal seepage at different gas pressures with He, N2 and CO2 was investigated. The results show that, in a given state of stress during the experiment, with the increase of gas pressure, the permeability of raw coal sample prone to outburst exhibits a significantly decrease, and then exhibits an increasing trend when reaching the extreme point. The law of Klingberg coefficient related to the stress state and the gas adsorption properties was also obtained. Under the same experimental conditions, the Klingberg coefficient of He is greater than that of N2; and the Klingberg coefficient of CO2 has minimum value; so the stronger the gas adsorption is, the smaller the Klingberg coefficient of gas goes. Klinkenberg coefficient decreases with the increase of effective stress. Under the same conditions, the permeability of He is greater than that of N2; the permeability of CO2 has minimum value; so the stronger the gas adsorption is, the lower the permeability of the coal sample goes. The results have important significance in revealing the mechanism of gas seenage. Dredicting coal mine gas disaster, and gas drainage and safety nroduction.

Mesoscopic analysis of the utilization of hardening model for a description of softening behavior based on disturbed state concept theory

Mesoscopic characteristics of a clayey soil specimen subjected to macroscopic loading are examined using a medi- cal-use computerized tomography (CT) instrument. Disturbed state concept (DSC) theory is based on the utilization of the hard- ening model. DSC indirectly describes material behavior by claiming that the actual response of the material is expressed in terms of the relative intact (RI) response and the fully adjusted (FA) response. The occurrence of mesoscopic structural changes of material has similarities with the occurrence of a macroscopic response of the material under loadings. In general, the relative changing value of a softening material is three to five times more than that of a hardening material. Whether special zones exist or not in a specimen cross section does not affect the following conclusion: hardening material and softening material show me- chanical differences with CT statistical indices values prominently changing, and the change is related to the superposing of a disturbance factor. A new disturbance factor evolution function is proposed. Thus, mesoscopic statistical indices are introduced to describe macroscopic behavior through the new evolution function. An application of the new evolution function proves the effectiveness of the amalgamation of a macroscopic and a mesoscopic experimental phenomenon measurement methods.

Blade Shape Optimization of Liquid Turbine Flow Sensor

Based on the characteristic curve analysis, the method using D(K^2) square difference of meter factor at different flow rates was developed to evaluate the performance of turbine flow sensor in this study. Then according to the distribution of entrance velocity, it was supposed that reducing the blade area near the tip could decrease the linearity error of a sensor. Therefore, the influence of different blade shape parameters on the performance of the sensor was investigated by combining computational fluid dynamics(CFD)simulation with experimental test. The experimental results showed that, for the liquid turbine flow sensor with a diameter of 10 mm, the linearity error was smallest, and the performance of sensor was optimal when blade shape parameter equaled 0.25.

Probabilistic analysis of geomembrane puncture from granular material under liquid pressure

A simplified probabilistic analysis of geomembrane punctures from granular material was presented when subjected to liquid pressure.The probability distribution of contact force between geomembrane and granular material was obtained based on the principle of equal probability and assumptions that grains are spheres with constant size.A particle flow code PFC3Dwas employed to simulate the contact process which indicates a good agreement with the theoretical probabilistic analysis.The odds of geomembrane puncture from grains of constant size were obtained by evaluating the puncture force which should not exceed the puncture resistance of geomembrane.The effects of grain radius,grain rigidity and liquid pressure were studied in more detail and displayed in graphs.Both high-level of liquid pressure and large grain can result in high risk of geomembrane puncture.The influence of grain rigidity on the geomembrane puncture odds is significant.For granular material with a grain size distribution,the geomembrane puncture odds can be estimated by the grain size distribution,served as weight function and it is a cautious design if the largest grain is chosen as the design grain size.

Kinematic analysis of shallow tunnel in layered strata considering joined effects of settlement and seepage

The purpose of this work is to predict the state of collapse in shallow tunnel in layered strata by using a new curved failure mechanism within the framework of upper bound theorem.Particular emphasis is first given to consider the effects of seepage forces and surface settlement.Furthermore,the Hoek-Brown nonlinear failure criterion is adopted to analyze the influence of different factors on the collapsing shape.Two different curve functions which describe two different rock layers are obtained by virtual work equations under the variational principle.According to the numerical results,the parameter B in Hoek-Brown failure criterion and the unit weights in different rock layers have a positive relationship with the size of collapsing block while pore pressure coefficient and the parameter A in Hoek-Brown failure criterion present a reverse tend.

Tubular electrocatalytic membrane reactor for alcohol oxidation：CFD simulation and experiment

A functional electrocatalytic membrane reactor(ECMR) was performed for the electrocatalytic oxidation of2,2,3,3-tetrafluoro-l-propanol(TFP) into high value-added sodium 2,2,3,3-tetrafluoropropionate(STFP),A computational fluid dynamics(CFD) technique was applied to simulate the hydrodynamic distributions along a tubular ECMR so as to provide guidance for the design and optimization of ECMR Two-dimensional simulation with porous media model was employed to predict the properties of fluid dynamics in ECMR.The experimental investigation was carried to confirm the CFD simulation.Results showed that a uniform distribution of permeate velocity along the tubular reactor with short length and large diameter could be obtained.TFP conversion of97.7%,the selectivity to STFP of 99.9%and current efficiency of 40.1%were achieved from the ECMR with a length of 40 mm and an inside diameter of 53 mm.The simulations were in good agreement with the experimental results.

Microstructure, martensitic transformation and mechanical properties of Ni-Mn-Sn alloys by substituting Fe for Ni

The effects of partial substitution of Fe element for Ni element on the structure,martensitic transformation and mechanicalproperties of Ni50-xFexMn38Sn12(x=0and3%,molar fraction)ferromagnetic shape memory alloys were investigated.Experimentalresults indicate that by substitution of Fe for Ni,the microstructure and crystal structure of the alloys change at room temperature.Compared with Ni50Mn38Sn12alloy,the martensitic transformation starting temperature of Ni47Fe3Mn38Sn12alloy is decreased by32.5K.It is also found that martensitic transformation occurs over a broad temperature window from288.9to352.2K.It is found that themechanical properties of Ni-Mn-Sn alloy can be significantly improved by Fe addition.The Ni47Fe3Mn38Sn12alloy achieves amaximum compressive strength of855MPa with a fracture strain of11%.Moreover,the mechanism of the mechanical propertyimprovement is clarified.Fe doping changes the fracture type from intergranular fracture of Ni50Mn38Sn12alloy to transgranularcleavage fracture of Ni47Fe3Mn38Sn12alloys.

Statistical mechanics and artificial intelligence to model the thermodynamic properties of pure and mixture of ionic liquids

In this paper, the volumetric properties of pure and mixture of ionic liquids are predicted using the developed statistical mechanical equation of state in different temperatures, pressures and mole fractions. The temperature dependent parameters of the equation of state have been calculated using corresponding state correlation based on only the density at 298.15 K as scaling constants. The obtained mean of deviations of modified equation of state for density of all pure ionic liquids for 1662 data points was 0.25%. In addition, the performance of the artificial neural network(ANN) with principle component analysis(PCA) based on back propagation training with28 neurons in hidden layer for predicting of behavior of binary mixtures of ionic liquids was investigated. The AADs of a collection of 568 data points for all binary systems using the EOS and the ANN at various temperatures and mole fractions are 1.03% and 0.68%, respectively. Moreover, the excess molar volume of all binary mixtures is predicted using obtained densities of EOS and ANN, and the results show that these properties have good agreement with literature.

Improvement Methods for Genetic Evaluation of Hanwoo Cows

A total of 1,101 heads were used to improve the selection of superior cows in Gangwon regional Hanwoo. Characteristics of each cow were analyzed using ultrasound evaluation and trace of reproductive potential. A comparison of live carcass traits classified by parity was analyzed in all characteristics. The results of the comparison showed all characteristic increased rapidly after the 2nd parity, and decreased after the 4th parity （P 〈 0.01）. The result of comparison classified by the group showed a tendency, whereas Back Fat Thickness Ultrasound （BFTU） and P8 Fat Thickness Ultrasound （P8-FTU） were significant （P 〈 0.01） thinnest in Pedigree group and using a lot of reproduction in advanced group. Also, we made comparisons of the cow＇s calves on the carcass traits among the group. High quality calves of the pedigree group showed 30.77%. These are the highest carcass traits in meat quality grade above 1＋ and yield grade above A. Frequency of fertilization failure per rump fat thickness showed a significantly （P 〈 0.0｜） higher difference. The average frequency of fertilization failure demonstrated 1.11 times of experimental Hanwoo cows. In the analysis, frequency of fertilization failure appeared 0.9 times at rump fat thickness below 5 mm. However, it is higher than average above 5 mm. The result of the study will be used to improve cows, select optimum semen, as well as contribute to the improvement of farms income.

Role of thermal martensite in shape memory effect of CoAl and CoNi alloys

To address the role of the HCP martensite in CoAl and CoNi shape memory alloys, the relationship between the shape memory effect （SME） and the content of the thermal and stress-induced HCP martensite was investigated in the solution-treated CoAl and CoNi alloys. In-situ optical observations were employed to investigate the contents of thermal HCP martensite before and after deep cooling and its influence on the stress-induced HCP martensite transformation and SME. The results show that the SME in both the CoAl and the CoNi alloys results from the stress-induced HCP martensite. The role of the thermal HCP martensite in both of them is the strengthening of the matrix. The much higher yield strength in the solution-treated CoAl alloy due to solution strengthening of Al is responsible for its better SME compared with the CoNi alloy.

Comparing potentials for gas outburst in a Chinese anthracite and an Australian bituminous coal mine

Gas outbursts in underground mining occur under conditions of high gas desorption rate and gas content,combined with high stress regime, low coal strength and high Young's modulus. This combination of gas and stress factors occurs more often in deep mining. Hence, as the depth of mining increases, the potential for outburst increases. This study proposes a conceptual model to evaluate outburst potential in terms of an outburst indicator. The model was used to evaluate the potential for gas outburst in two mines, by comparing numerical simulations of gas flow behavior under typical stress regimes in an Australian gassy mine extracting a medium-volatile bituminous coal, and a Chinese gassy coal mine in Qinshui Basin(Shanxi province) extracting anthracite coal. We coupled the stress simulation program(FLAC3D) with the gas simulation program(SIMED II) to compute the stress and gas pressure and gas content distribution following development of a roadway into the targeted coal seams. The data from gas content and stress distribution were then used to quantify the intensity of energy release in the event of an outburst.

Characterizing and Analyzing the Airflow Field inside the Nozzle Block of Murata Vortex Spinning

A three-dimensional computational fluid dynamics model is developed by software Fluent 6.2, to simulate the flow field inside the nozzle block of the Murata vortex spinning. The flowing state and the distribution law of static pressure and velocity are characterized and analyzed. The relationship between the flowing state and the structure of the vortex spun yarn is also discussed. The research results can enhance the understanding of the yarn formation principle from viewpoint of the airflow field law inside the nozzle block of Murata vortex spinning.

Phase Transitions of an Epidemic Spreading Model in Small-World Networks

We propose a modified susceptible-infected-refractory-susceptible （SIRS） model to investigate the global oscillations of the epidemic spreading in Watts-Strogatz （WS） small-world networks. It is found that when an individual immunity does not change or decays slowly in an immune period, the system can exhibit complex transition from an infecting stationary state to a large amplitude sustained oscillation or an absorbing state with no infection. When the immunity decays rapidly in the immune period, the transition to the global oscillation disappears and there is no oscillation. Furthermore, based on the spatico-temporal evolution patterns and the phase diagram, it is disclosed that a long immunity period takes an important role in the emergence of the global oscillation in small-world networks.

Density matrix of two interacting particles with kinetic coupling derived in bipartite entangled state representation

A density matrix is usually obtained by solving the Bloch equation, however only a few Hamiltonians＇ density matrices can be analytically derived. The density matrix for two interacting particles with kinetic coupling is hard to derive by the usual method due to this coupling; this paper solves this problem by using the bipartite entangled state representation.

Number Concentration of Cylindrical Particles in a Fluidized Bed

In this study, a three-dimensional model based on RANS, slender-body theory and Newton-Euler dynamics is established to study the number concentration, one of the most important fluidization characteristics of cylindrical particles. Also, the effects of interaction between cylindrical particles are taken into account by introducing the rigid collision dynamics. To validate the model, the fluidization experiments of cylindrical particles in a cold-state fluidized bed are carried out. The number concentration characteristics of cylindrical particles are obtained from computational fluid dynamics (CFD) simulation. It is found that cylindrical particles arriving at the exit of the riser the earliest come from the near-wall regions, the horizontal transfer of so many cylindrical particles from the radial centre regions to the near-wall regions is evident. Meanwhile, there is no distinct relationship between the number concentration and inlet wind velocity.