Search results

Hierarchy of dislocations (dislocation, dislocation pile-ups, polygonal walls, small-angle grain boundaries, etc.); 2.4.
This effect is related to violation of polarisation coordination of separate grains when particle size is below some critical value.
Thus, as shown above, development of advanced materials meets a number of unresolved problems at each structural level.
For the past 20 years this theory found a number of major successful applications in thermal physics and fluid mechanics of porous materials (existence of some porosity is inevitable for the majority of heterogeneous solids), therefore this theoretical approach can serve as a basis for the analysis of physical phenomena in other physical systems.

In the experiment, a number of ablation laser pulses to deposit the Al layer and the Fe layer were 300 and 1,000, respectively.
A mean grain size of the Fe particle on the substrate is (a) 10.1 nm and (b) 14.5 nm.
Fig.3 Properties of CNTs gas sensor prepared at C2H4:Ar:H2=1:1:1, a number of laser pulses of 1,000 at 10Hz.
The AFM images show that Fe fine grains were produced on the Al buffer layer by PLD.

Introduction Since the first synthesis of an amorphouse alloy in 1960 a great number of amorphous alloys have been produced during the last two decades.
Inoue defined three empirical rules for the bulk amorphous alloys systems [4]: (a) negative heat of mixing between each pair of alloying elements, (b) atomic mismatch at a minimum rate 12 %, and c) the minimal number of alloying elements is three.
The Ag crystals identified by XRD have appeared in two forms: among the dendrites (Fig. 5) and as primary crystallized grains (Fig. 6).
SEM images of the cross section of the Cu37,5Zr37,5Ag22,5 wedgeshaped sample Primary crystallized Ag grains have been identified in the Cu40Zr35Ag25 and the Cu37,5Zr37,5Ag25 samples, so based on this fact the ternary eutectic point [2] is located in the territory with less Zr content.

In the certain amount of vanadium content, grain and precipitate size and performance met the requirements of HRB400E and had nothing to do with the type of vanadium-containing products at the same dimension size, vanadium alloys in Table 1 were the intermediate products with different cost, so it is feasible to take the intermediate product as vanadium alloy in producing vanadium-containing seismic resistant rebar.
Table 1 Properties of HRB400E with different vanadium-containing alloy size [mm] vanadium alloying V [%] grain size precipitate size [nm] performance Rel [MPa] Rel/R0 Rm/Rel Φ16 FeV 0.032 9.0 12.6 460 1.13 1.31 V2O5 0.033 8.6 14.2 452 1.15 1.31 V-ball 0.034 8.9 13.7 458 1.15 1.32 V-slag 0.032 8.7 15.5 451 1.13 1.31 V-iron 0.033 8.9 13.9 455 1.14 1.31 According to new vanadium alloy and combined with the current steel-making equipment, three distinctive low-cost steel-making processes chains were established for producing vanadium-containing seismic resistant rebar.
Vanadium content is more, vanadium slag alloying would be faced with a large number of bulk vanadium slag floating on the molten steel surface and effect vanadium absorption rate, therefore, we considered vanadium slag was pressed into vanadium ball and developed vanadium ball alloying.
Affect factors on performance decreased were large number of impurity elements in vanadium-containing molten iron.

Currently, for high performance applications in automotive industry, a large number of metal matrix composites (MMCs) have been developed.
This technique is an efficient method to reduce casting defects because of refinement of grains and reinforcement phase.
Furthermore it can be observed that with increasing the extrusion ratio the fragmentation of Gd intermetallic compounds (IMCs) are more considerable in grain boundaries of the composite compared to lower extrusion ratio.
The fracture surface of the extruded and heat treated composite shows high levels of fine dimples and reduced number of decohered particles.

Furthermore, a large number of grains cut the workpiece surface many times, which improves the surface quality of the workpiece and reduces the surface roughness.
As shown in Fig. 5, the surface roughness of the workpiece is higher and the surface quality is worse due to a large number of graining trajectories of different depths on the CG surface, while the surface roughness of the workpiece machined by UAG is smoother and the surface roughness is lower.

For example, Bi2WO6 microsphere[6] prepared by hydrothermal method has a large number of pores which increase the photocatalytic performance, nested Bi2WO6 synthesized by microwave hydrothermal method also increase photocatalytic performance by the same way, preparing Bi2WO6 nanomaterials with different morphology by altering external conditions[7,8], the influence of calcination temperature on photocatalytic performance[9], changing optical properties of Bi2WO6 by doping N[10], F [11] and Er3+[12], extending visible light response range or restraining the recombination of optical electron-hole pair by compositing Bi2WO6 with Co3O4[13], TiO2[14] and graphene[15].
There are a large number of optical electronics when increasing the amount of catalyst to some extent, that’s why catalytic performance gets improved.
Carbon microspheres are micrometer grain and belong to the orthorhombic system.
After calcination, Bi2WO6 grain has high crystallinity, perfect crystal form and small size of 200-300 nm.

Introduction Carbide and boride of zirconium show a number of excellent properties such as high melting temperature, high strength, high thermal and electrical conductivity, and chemical stability.
These results indicate the size reduction and the increase in the lattice strain of Zr metal particles, and the disappearance of the stacking order of the graphite layers and the formation of disordered carbon with finely divided grains.
During mechanical activation by grinding, the breaking down of graphite grains into nanocrystallites was often observed and the introduction of lattice defects, such as shearing and turbostratic stackings of 002 planes into the crystallites, can be sufficiently expected.

Quartz sand had a relatively broad worldwide absorption peak in the wave number 3100～3700cm-1.
The results showed that HF could dissolve these newly formed inclusions and lead to internal water in quartz grain being released.
Meanwhile, HF could dissolve these newly formed inclusions and led to internal water in quartz grains being released.

Shale mudstone Fully weathered, earthy, texture and structure were damaged, bedding and schistosity can still be identified, contain a little quartz grains, and can crush with hand and mine easily.
Sandstone Fully weathered, contain much more quartz grains and sandstone fragments, and can crush with hand Shale mudstone Fully weathered, texture and structure has been most of the destruction, Rock crushing, the integrity is poor, and easy to break by hand, water-weakening.
The tamping number of each point is determined by the trial ramming of the site, the Criterion of Stopping Tamping is the average settlement of the last two tamping is less than 200mm.