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Compared with the sample without (PS-b-PAA) (Fig.4 a), the particles in the ZnFe2O4/TiO2 film are ordered arrangement, more dense, and every particle surface contained a large number of micropores which is close to the sample prepared by hydrothermal synthesis [10], which the template agent is playing self-assembly role as well.
In ZnFe2O4/TiO2 grains forming process, Except for nucleating and growing into grains in the space of PS-b-PAA structures, ZnFe2O4/TiO2 produces orientative whiskers on primary grain matrixes in other small frame structures, and fluffy ZnFe2O4/TiO2 particles are obtained with greater specific surface area after sintering.
An amount of template (PS-b-PAA) can form a great number of micropores on particles surfaces, and arrange orderly the particles in the films.

TEM image of a single V2O5 fibre (Fig. 1b) shows that after calcinations, the fibre has a loose and porous structure and a coarse surface, with its grain size of ~150 nm, which is believed to be due to the rapid decomposition of PVP.
These sharp peaks suggest a high degree of crystallinity and relatively large grain size.
The molar ratio of V4+ to V5+ can be directly calculated by equation: (2) where N and S represent the number of certain ions per unit volume and peak area, respectively [18].
Furthermore, according to the TEM results, the obtained fibres show a loose structure with submicron pores, where the V2O5 grains contact with each other at an area narrower than the fibre’s cross-section.
In a number of studies, the small-polaron theory has been successfully applied to account for the electrical properties of V2O5 film and nanowires [11,12], and the motion of the carriers is supposed to be a thermally activated hopping process.

The hardening response of the as-cast sheet (homogenised at 345°C for 4 hrs) and the rolled strip, upon artificial ageing at 177°C in oil, was determined by measuring the Vickers hardness number (VHN) at a load of 49 N.
It is clear from the table that the strength of the age-hardened Mg-4Zn alloy is still lower than AZ31B and the reason for this is self-evident when the grain size of the HR&A alloys are compared (Figure 3).
The grain size of Mg-4Zn strip is about 3 times bigger than that of the AZ31B strip.
Work is in progress to achieve a grain size comparable with that of AZ31B in the Mg-4Zn alloy by thermomechanical processing.
Some advantages of this alloy over AZ31B were the lower time for homogenisation, less number of roll passes to achieve the same thickness (5 passes instead of 6) at lower rolling temperature and significantly lower flow stress during deep drawing.

Introduction The electric fatigue of ferroelectric and antiferroelectric materials under high a. c. field, namely decay of the switched polarization and the consequent field induced strain with cycle number, has been the major hindrance for their applications as non-volatile memory devices and actuators [1].
Table 1 Compositions and properties of the antiferroelectric ceramics Material Composition Grain size [µm ] ρrelative [%] EAFE-FE [kV/mm] SAFE-FE [×10-3 ] PAFE-FE [C/m2 ] C1 Pb0.97La0.02(Zr0.77Sn0.14Ti0.09)O3 ~6.5 >98 3.9 2.7 0.39 C2 Pb0.88Ba0.10La0.02(Zr0.55Sn0.35Ti0.10)O3 ~2.0 >99 1.6 0.8 0.24 C3 Pb0.97La0.02(Zr0.55Sn0.33Ti0.12)O3 ~3.1 >98 2.5 2.4 0.33 An inductive strain gauge was employed to measure the field induced longitudinal strain of the disc samples before and after cycling.
Numerous etch grooves can be found within grains (Fig. 4(b)).
SEM micrographs of the polished-etched surfaces of the fatigued samples show severe damaged structure with a large amount of grains peeled off from the surface as a result of the attack of the acid solution.
The former is based on the idea that microcracks reduce the local effective field or yield conductive corrosion pathways in the material, thus decreasing the number of domains that switch in the proximity of such cracks.

The reduction of carbon content leads to decrease in the fraction of relatively large M23C6-type carbides, while a number of finely dispersed MX-type precipitates increases [7-9].
The arrangement of high-angle grain boundaries (HABs) having misorientation above 15° suggests that the hot working resulted in the development of somewhat elongated austenite grains along the direction of metal flow.
The prior austenite grains are split by various boundaries into finer structural elements, i.e. martensite packets, blocks, and laths.
It is clearly seen in Fig. 2b that the TMLS in the studied material contains a number of fine plate-shaped particles, which are oriented along {2 0 0} plane of ferrite matrix.

The ratio of hardness and bending strength 1 - ultrafine-grained hard alloys; 2 - WC-Co group; 3 - (W-Ti-Ta) C-Co) group; 4 - (W-Ti) C-Co group In this article, we are interested in hard alloys of the WC-Co (single-carbide) and (W-Ti) C-Co (two-carbide) groups, as they are largely used in the machining of various metals.
In case the carbide content and the size of carbide grains decrease, the thermal conductivity increases.
The consequence of this is the weakening of the bonds that hold the carbide grains or groups of carbides in the hard alloy, digging and carrying them away by the boundary volumes of the material being processed.
In addition, there are a number of techniques for machining work surfaces, which provide them with additional hardening; the most effective technique is the method of applying the special coatings of solid compounds onto the surface of the cutting tool.
After cutting with advanced plastic deformation, the surface roughness decreases dramatically (in many cases by 2-4 times), thus reducing the number of technological transitions, and also improving the surface micro profile (in particular, the length of the reference line increases).

When the pattern-less sand mould is processed, the tool scrapes the sand mould, and cracks occur between the sand grains on the sand surface after scraping.
The sand grain shape of the pearl sand is round, the bonding bridge of the sand mould is more relatively uniform, the mould surface is not easy to crack, so its surface wear resistance is better.
The sand grain shape of silicon sand is somewhat in between, and the surface wear resistance is also between the two.
Under the action of extrusion pressure, the space between sand particles is tighter, which increases the number of sand bonded bridges and the contact area of the bonded bridge.
This is due to the coating thickness of the sand increases as the resin content increases, so that the bonding bridge of the sand increases, the sand mould strength increases, and the number of cracks generated by the sand cutting is reduced, so the surface wear resistance of the sand mould improved.

It is important to note that the XRD patterns of Y2O3, NiO and MnO2 were reported with JCPDS card numbers for both the bulk Y2NiMnO6 and Y2NiMnO6 ceramics.
Consequently, in the case of space charge (interfacial) polarization occurs when mobile charge carriers are impeded by a physical barrier (i.e. grain boundary) that inhibits charge migration.
Interestingly, the charges then pile up at the barrier, producing a localized polarization within grains.
However, the effect of large grain size is associated with peak’s height; it can clearly be observed that sintering time of 12 hours has yielded a high peak for various temperatures.
However, the sample at 1400℃ with sintering time of 12 hours has the lowest number of tanδ about 0.0142 at the highest frequency of 108Hz, while the sample at 1400℃ and sintered for 24 hours has the highest value of tanδ.

For instance, it has been found on a number of recent sites in France that HPC could be sticky and difficult to pump, while it had a high fluidity [2].
It was believed that numerous small spherical particles of SF were distributed within the spaces between cement particles, eliminating the interlocking of cement grains and making the grain ''mobile.''
A number of points still need to be further explored, e.g., the nature and granular distribution of the fines in aggregate.
The combination of the ultrafine cement with Portland cement leads to a bimodal grain size distribution.
Conclusions Comb-type copolymers may be less sensitive to this effect because of the PEO side chains and reduced number of ionic groups.

In this method, the total number of design points is F+2k+n0, where, F is full/fraction of 2k; n0 is number of center points.
The total number of designed points is 52.
Size-Ratio The depth of cut, and consequently, finished surface quality depend much on the abrasive grain size.
Application of fine grains is effective obtaining smoother surfaces.
Therefore, the most variation in surface roughness happened using particles with mesh number of 325-400 and the most material removal by particles with mesh numbers of 100-140.