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In research of foreign scholars on micro-hardness and microstructure of grinding layer, Since the 1990s years BROCKHOFF had carried through research on the grinding hardening experiment of GCr15 and 40CrMnMo, And some achievements had been made[1];ZARUDI et al had researched texture of grinding hardness layer, and simulated texture change[2],but did not consider that temperature field distribution affected on austenite grain sizes of different layers depth.
The influence factors and the change rule are going to be analyzed. 1 Grinding experimental conditions 1.1 Experimental material and machining processes Here 20CrMnTi of spiral bevel gears was commonly selected in automobile gear material.
Moreover, the distance from thicker martensite structure of hardening area to grinding surface increased as augmenting grinding depth a, and the distance was slightly influenced by grinding wheel speed vs or gear feeding speed vw. 4 Experimental analysis of micro-hardness and structure of grinding burns and cracks Fig.4 Central microstructure of normal grinding small gear(1000×) Gray-white lath martensite Bainite White ferrolites 4.1 Influence of grinding temperature on burns Grinding temperature would affect change of metallographic structure, and grinding burns and discoloration would happen when fatally.
This showed that burns were affected by temperature, the temperature of this area was higher than one of gear tempering temperature(150℃).
[2] ZARUDI I,ZHANG L C.Mechanical Property Improvement of Quenchable Steel by Grinding[J].Journal of Materials Science, 2002, 37(18):3935-3943

The Geotechnical Engineering Chemistry is one of the main methods to change the loess sites engineering properties [9].
As for grouting to stake, the thick liquid interact with the foundation loess by chemical reaction, can increase its Physical characters by mechanical loadings.
The loess has loose grains accumulation in microstructure, so need to rebuild and modify its weak mechanical properties[10,11].The adhesive force of the cement materials mainly from CaO, CaCO3 and CaSiO3, Fe2O3.2H2O, and other week alkaline salt fragments, their cementation is weaker with low water-resistance ability.
SEM analysis Further study loess microstructure changed and its mechanical properties before and after modification, the original loess is show as in fig.2.
The acid modified meanings is test to be greatly changed the loess nature mechanism of easily to deformation and reduced the residual deformation coefficients under loading. 3 Because of the added chemical materials have no toxicity to cause environmental pollution and have no affect to continue farmed.

Instability is the factor that causes the most significant technical problem in the drilling operation and it is also a major source of lost time and high cost [1].
Thus, the stability of oil wells has been studied considering the chemical and mechanical aspects of the rock, mainly with respect to shale-fluid interactions [4].
The stability of shales rich in clay are deeply affected by its complex physical and chemical interactions with drilling fluids [6].
The CEC is a property that derives from the structural characteristics of a clay mineral, and the estimation of this parameter is essential for a more accurate evaluation of reactive formations, as each clay mineral has a range of specific values.

The shot-noise-limited sensitivity of a magnetic field measurement is given by [10] (1) where g is the ground-state Landé factor, μB is the Bohr magneton, is Planck’s constant, N is the number of atoms involved in the measurement, t and τ represent measurement time and atomic coherence time respectively.
This material has excellent temperature and aging resistance, great mechanical strength to process easily.
The cell is placed in the center of the oven and sealed with heat-resistant adhesive to maximize the heat preservation property.
However, the residual magnetic field from the platinum resistance was of the order of few dozens nanotesla, which affected the experiment condition seriously.

Furthermore, a smaller grain size can also improve mechanical properties, in particular to elongation.
Especially, avoiding or at least reducing the so-called Si poisoning is of extremely importance to achieve a well-control of the solidification microstructure and a significant improvement of mechanical properties in Al-Si-Mg based alloys.
The presence of the Ta-rich layer at the TiB2 interface indicates that heterogenous nucleation, together with the growth restriction, is another important factor affecting the grain refinement.

Up to now, it has not commonly used for hydraulic structures (especially high arch dams) due to the complexity in material properties and construction conditions [14,15,16,17,18].
Then base on the assumption that normal stress and shear stress at arch-cantilever sections contributed linearly from upstream to downstream, using the Material Strength method to calculate again stress components by which affects of concentrated stresses reduced significantly.
In taking the effect of contraction joints into consideration, most complicated problems are that how to model the contact area as well as to determine mechanical parameters corresponding to the selected model.
Although taking earthquake into account to lead the maximum Y-component of tensile stress is relatively large, but in the Chinese Hydropower Industry Standard DL 5073-2000 [23] defines, of which material properties of a dam working in dynamic state, values of specified compressive strength is assigned 30% greater than this is in static state; and a value of specified tensile strength is equal 10% of specified compressive strength.
J, Mechanical Model for Hydraulic Structure Contact Problem and Its Applications in the Three Gorges Project, Ph.

The selection of marine engineering floating pier structure Considering the needs of marine engineering floating pier structure and the characteristics of grid structure, the design concept of grid structure was applied to design marine engineering floating pier structure, the new marine structure should have sufficient strength and stiffness, be easily manufactured and constructed, and reducing the affect of waves and ocean currents is crucial.
Material properties Table 1 Material properties of steel Model Density [kg/m3] Modulus of elasticity [GPa] Poisson's ratio Yield stress [MPa] 7850 210 0.3 235 The selection of unit.
(the zoom factor of deformation is 5) Fig. 10 1st orde vibration mode Fig. 11 2nd order vibration mode Fig. 12 3rd order vibration mode Fig. 13 4th order vibration mode Fig. 14 6th order vibration mode Fig. 15 8th order vibration mode Fig. 16 10th order vibration mode The analysis of random response under wave force.
The mechanical property analysis of Deep-sea drilling riser[J].

It comes to the conclusion that the main factor which has an influence on the pipe flow is jet and the mainstream velocity ratio.
Zhang etc [16] researched influence factors and mechanism of the active control of helicopter rotor airfoil flow field on zero quality jet technology.
It analyzed that the difference with jet or without jet and the value of interference factors between numerical calculation and experimental results.
Fomin etc [40] researched on counter-flow jet with cold and hot gas in the supersonic flow field by experiments and analyzed the influence factors of the flow field.
Properties of aspect-ratio-4.0 rectangular jets in a subsonic cross-flow.

Introduction Metallic multilayered composites have attracted much attention due to great potential of such layer-to-layer structure to practical application in mechanical and physical aspects.
Substantial enhancement of mechanical properties, such as hardness, wear resistance, fatigue endurance limit etc.
Both Berkvoich nanoindenter (tip radius ～50 nm) and Vickers microindenter were employed to examine mechanical response of the Cu/Au and Cu/Cr multilayers at room temperature.
These were usually thought to be a pseudo behavior masking the inherent mechanical properties.
While at the submicron scale or more, deformation and fracture are mainly affected by grain orientation because dislocation slip becomes more dominated.

When too much learning material is exposed in a classroom, learners’ retention will be negatively affected.
‘Time-to-competency’ is a major factor of determining competitiveness of all companies.
Georgia Institute of Technology Digital Signal Processing, Mechanical Engineering University of Illinois Online, Urbana Expert Systems, Microelectronic Processing, etc.
In e-Learning, knowledge which is an intellectual property is placed on the Internet and can be accessed by individual learners.