Search results

To investigate mechanical behavior of ice under confined conditions, the triaxial testing was done by a number of scholars.
The influences of other factors such as specimen homogeneity, grain-size, density, temperature and the state of stress on mechanical properties of ice are also observed under this test (Assur, 1980).
Afterward, the sieved grained ice was put in a cylindrical mold to make cylindrical specimens with a height of 125.0mm and a diameter of 61.8mm.
The pressure crushing and melting decrease the ice bonding force between solid grains.

Ferrite Martensite a) b) Fig. 3 – Cut-edge micrography (150X). a) milled edge; b) AWJ cut-edge In both cases, there is no microstructural changes, HAZ or plastic deformation of the grain close to the cut-edges.
The martensite seems to have an important role in the ferritic grain deformation.
The equation of the milling 1st serie, milling 2nd serie and the AWJ cutting fatigue design curve is, respectively, Eq. 1, Eq. 2 and Eq. 3: [MPa] (1) [MPa] (2) [MPa] (3) where sa is the applied alternating stress and Nr is the number of cycles to failure.
Conclusions The metallographic analysis did not reveal microstructural changes or plastic deformation of the grain in the cut-edge.

In the crystallization process, it can form the crisscross lap, grain symbiotic phenomenon, the structure is relatively close-grained, the add of retarder can reduce the slurry of saturation in degree, reduce or delay the nucleation precipitation, which provide a space for the development.
At the same time retarder will increase gypsum slurry over the duration of the saturation, the last time to grow more, grain will have enough hydration products continue to grow up.
But the lower nucleation number may reduce sclerosis density in some degree, reduce sclerosis intensity.

Consoli et al. [4, 5] made a large number of tests about cement cemented sand in 2007, they defined void/cement ratio as the key parameters of unconfined compressive strength, in 2011, they introduced the curing time to optimized the function of unconfined compressive strength.
The grain-size distribution of quartz sand is shown in Fig.1 and Table.1.
Grain sizes (mm) Cu Cc d95 d60 d50 d30 d10 1.375 0.414 0.379 0.318 0.266 1.55 0.92 Table.1.
Grain size distribution 0f tested sand Sample preparations.

It is found that the as-sintered products are mainly composed of Ti2AlC matrix and Al2O3 reinforcement, and the in situ formed fine Al2O3 particles tend to disperse on the matrix grain boundaries.
The greater enhancement in values observed in these composites in comparison to monolithic aluminum is due to grain refinement, small particle size and good distribution of alumina particles, and low degree of porosity which leads to the effective transfer of applied tensile load to uniformly distributed strong alumina particulates.
The high wear rate was also attributed to the large number of reinforcement particles or fibers being fractured or de-bonded, and which subsequently participated in the abrasive wearing of the composites.
The greater enhancement of tensile stress observed is due to small particle size and good distribution of alumina nano powder, effective transfer of applied tensile load to the alumina nano particles and grain refinement of aluminum alloy matrix.

Therefore, a large number of coal under buildings, railways and water bodies (under three for short) are mined by using backfill mining technology[1-3].
The mechanical parameters of each stratum Surrounding rock (from above down) Bulk density γ/g.cm-3 Uniaxial compressive strength R/MPa Uniaxial tensile strength Rt/MPa Cohesion C/MPa Angle of internal friction Φ/° Elastic modulus E/GPa Poisson ratio μ 1 Ground soil layer 2.2 2.1 0.03 0.1 25 1.26 0.42 2 Sandy mudstone 2.32 14 1.12 0.52 30 4.38 0.32 3 Medium grained sandstone 2.64 40 1.80 4.25 37 11.65 0.21 4 Sandy mudstone 2.32 14 1.12 0.52 30 4.38 0.32 5 Medium grained sandstone 2.64 40 1.80 4.25 35 11.65 0.21 6 Sandy mudstone 2.32 14 1.12 0.52 30 4.38 0.32 7 Sandstone 2.5 18 1.81 2.70 36 11.05 0.22 8 Medium grained sandstone 2.64 40 1.80 4.25 37 11.65 0.21 9 1 coal 1.6 12 1.43 1.50 18 0.45 0.42 10 Sandy mudstone 2.32 14 1.12 0.52 30 4.38 0.32 11 Fine sandstone 2.5 38 1.81 2.70 34 11.05 0.22 12 Sandy mudstone 2.32 14 1.12 0.52 30 4.38 0.32 13 2 coal 1.6 12 1.43 1.50 18 0.45 0.42 14 Sandy mudstone 2.32 14 1.12 0.52 30 4.38 0.32 15 3 coal 1.6 12 1.43 1.50 18 0.45 0.42 16 Sandy

Murayama’s reagent attackes WC grains and roughens the substrate surface, thus, favoring the adhesion of the diamond coating by mechanical interlocking; the choice of the Caro's acid is made due to its well-known strong reactive etching affinity towards cobalt element, Caro’s acid oxidizes the binder to soluble Co2+ compounds, thus reducing the cobalt concentration[6].
Table 1 Deposition parameters Acetone concentration 1%-3% Pressure 2000-3000 [Pa] Filament temperature 1500-2000 [oC] Substrate temperature 800-900 [oC] Bias current 0.02 [A] Deposition time 5-6 [h] For the characterization, the scanning electron microscopy (SEM) is adopted to characterize the surface morphology, microstructure and grain size.
The slight shift from 1332cm-1 in wave number is considered to be due to the residual compressive stress.
The SEM study shows a dense, continous layer of diamond films, with the grain size of 2-4 μm and thickness of ~8 μm, is uniformly deposited on the substrate surface.

The reason for this behavior is presumably related to that the Al2O3 layer is gradually crystallizing during annealing at 900°C, containing grain boundaries promoting leaking current, while during annealing at 400°C the Al2O3 layer remains amorphous.
Gate bias voltage 0.5V, probing frequency 10 6 Hz; #1, #2 and #3 denote serial numbers of exposure. 0 10 20 30 40 50 50 60 70 80 90 100 110 120 25% O2 25% O2 25% O2 25% O2 0.5% H2 0.5% H2 0.5% H2 0.5% H2 annealed at 900°C measured at 400°C Ctotal [pF] Time [min] gate bias 1V gate bias 5V depicted in Fig. 5 (two R-CPE parallel connections in series).
According to basic theory of IS [2], the two sets of parameter values (R1, C1, n1) and (R2, C2, n2) extracted from the IS spectra suggest the existence of a nonuniform gate dielectric, i.e. one consisting of grains and grain boundaries.

It can be seen that the CVD diamond film (Fig.1a) exhibits a rugged surface covered by well-faceted diamond crystallites with grain size of 2~3 µm, most of which had sharp octahedral shape and exhibit <111> or <100> crystallographic orientations.
Comparatively, the DLC film is mainly consisted of amorphous carbon phase, thus the surface of DLC coated milling tool is smoother and no discernable diamond grains can be observed (Fig.1b).
The slight shift from the 1332 cm-1 in wave number was owing to either a compressive residual stress and/or a convolution of the microcrystalline domain size.
Another peak at around 1250 cm−1 is also visible, which is generally attributed to the amorphous carbon with high concentration of sp 3 bonds, which existed on the grain boundary of the diamond crystals.

The problem space is partitioned by identifying very coarse grained components, and then the components and the cooperation rule are aggregated into a logical architecture, and the logical architecture is validated.
In turn, the coarse grained component is partitioned into fine-grained components, and so on iteratively until the desired granularity is achieved.
For each Business Object (BO) in the whole system, EBOMF designates a unique integer code named “Object ID” as the global index number.