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The longer the reaction time, the more complete the grain, the more uniform the morphology.
Adjuvants have an important effect on the growth of SnO2 grains, which can promote the growth of SnO2 grains with preferential orientation, that is to promote the growth of SnO2 grains in a certain direction and inhibit the growth of tin oxide grains in other directions.
And ammonia and urea due to the reaction is not enough to get the grain size is small, so the reunion and uneven appearance is shown.
It can be seen from Fig.3 that when the molar ratio of salt to alkali is 1: 4, the grain size obtained is larger and more uniform.
From the whole, the concentration of SnCl4 0.05 mol/L, NaOH as auxiliaries, salt and alkali molar ratio of 1: 4,200 ℃ insulation 4 days of the environment, the characteristic peaks have been quite obvious, a large number of crystal phase has been formed, and crystal phase is very complete.

In representative regions, average grain diameters of 600-1000 individual grains were measured to determine average grain size (results equivalent to intercept method, ASTM E112-113).
The composite μ-map indicates presence of both fine grains and heavily elongated grains in the specimens deformed in the region A.
(a) (b) Fig. 2: a) Composite µ-map : Numbers- average grain size (µm), white lines – heavily elongated grains, loops (A), (B), (C) – unstable domains ; b) Flow instability in Region A (b) (c) (a) Fig. 3: a) Q2 composite µ-map; abnormal growth in instability regions b) (B); and c) (C) Qualitative examination of microstructure obtained from regions (B) and (C) shows no signature of instability/ To address this, the individual components of microstructure have been studied in isolation.
The resulting microstructure contains some large grains and several small grains (Fig. 3(b)).
Since grains of Q3 and Q4 groups are larger in size than those of Q2 group, it is expected that the Q3 and Q4 grains (of specimens from the region C), are a result of abnormal grain growth.

The deformation texture was simulated with the grain cluster texture model GIA ('Grain Inter-Action'), which is a Taylor type texture model that takes grain interaction into account.
After discretization of the starting texture into 4000 single grain orientations assuming triclinic sample symmetry these grains were randomly grouped into clusters of 8 grains each.
Besides the deformation texture, the number of different slip systems NGLS activated during the complete deformation in each grain, the relaxed deformation tensor history ( ()trelaxedijε& ) of each grain, and the total amount of shear relaxation in each grain ( relaxshear vM − ε ) were important output quantities of the GIA model for downstream simulations [6,11].
Finally, a high number of different active slip systems NGLS in grains was connected to faster ODR kinetics, essential to form viable GB-nuclei [6,11].
The relative contributions (Frand, FGB and FTB) of the three distinguished nucleation mechanisms to the total nucleation texture were based on the frequency of the related sub-structural features, i.e. the number of grains with shear bands nrand, with fast recovery kinetics nGB, and with TBs nTB, respectively.

In the abnormal working stage of a blade, however, the working surface of the blade is displayed mainly with pulled out diamond, flatted diamond, macro-fractured diamond grains.
A layer of diamond abrasive grains with Ni- base bond was electroplated at the inner edge of the stainless steel substrate.
When the fracture along the diamond grain happened, the diamond grit was pulled out of the bond before completing its effective working life.
In the abnormal working stage of a blade, the working surface of the blade is displayed mainly with pulled out diamond, flatted diamond, macro-fractured diamond grains (See Fig.2), the number of effective cutting edge on the working surface decreases.
In the abnormal working stage of a blade, the working surface of the blade is displayed mainly with pulled out diamond, flatted diamond, macro-fractured diamond grains, the number of effective cutting edge on the working surface decreases.

Although the surface topography limited the number of pixels yielding high-quality diffraction patterns, orientation imaging revealed that the surface granules predominantly exhibit single-crystalline domain structures.
Although the number of pixels yielding high-quality EBSPs was limited due to surface roughness, orientation imaging revealed that the granules predominantly consist of single-crystal domains.
Prouteau, Low angle grain boundary transport in YBa2Cu3O7-δ coated conductors, Appl.
Murakami, Transmission EBSD (t-EBSD) to determine grain and grain boundary properties on nanostructured superconductor samples, J.
Xiong, The effects of grain boundaries on the current transport properties in YBCO-coated conductors, Nanoscale Res.

Even given the large number of computations, however, the LMBP algorithm appears to be the fastest neural network training algorithm for moderate numbers of network parameters [8].
Therefore only the number of hidden layers and the number of neurons in each layer need to be designed before training the ANN model.
As a measure of the cutting severity at individual grains, hm can be written as [9]: 4 1 2 1 2 1 )()() tan 3 ( s p s w m d a v v C h q =
(1) where C is the active grain density and θ is the semi-included angle of the active grain point which is assumed to be triangular.
In spite of the big difference in material removal rate, the maximum grain depth of cut for the maximum wear performance is comparable.

Fe- and Mg-based alloys, along with a number of advantages, also have certain disadvantages.
In addition, there are a number of works indicating that zinc oxide has antitumor cytotoxic activity [15, 16].
The grain size of α-Zn is 40 ± 4 µm and 32 ± 3 µm for Zn-1%Mg and Zn-1%Mg-0.1%Ca alloys, respectively.
It was shown that the grain boundary interlayer consists of a mixture of Mg2Zn11 and MgZn2 phases [21].
The elongated grains with 20 – 30 µm in width and ~100 µm in length are formed in both alloys after RS.

At the junction of weld and heat affected zone, the hardness begins to increase greatly, and the highest point of hardness is greater than that of base metal, which is caused by the inhomogeneous microstructure and a large number of dislocations in the fusion zone.
In (a) figure, the larger grain size in the lower part is ferrite, and the upper part is acicular ferrite.
The coarse grain zone can greatly improve the toughness of the material, and the strength decreases slightly (b) the coarse grain zone of 50-90 backing welding is composed of fine acicular ferrite distributed in the original austenite grains.
Acicular ferrite is relatively small, with large angle grain boundary, and has strong anti crack propagation ability.
Among them, the acicular ferrite zone has the highest strength, followed by the fine-grained zone, and the coarse-grained zone has the lowest strength.

TG-DTA, XRD and TEM analyses showed that the reaction temperature was 800℃, the calcining time was three hours, and the product was pure ANNT in well-dispersed grain structure (45nm in average).
Under wet chemical method condition, the substrate could be mixed homogeneously, and the product was of small and uniform grain.
Experimental Procedure Ta2O5(analytical grade)and Nb2O5(analytical grade) were mixed homogeneously in tetrafluoroethylene cup according to the stoichiometry of ANNT and dissolved completely by addition of hydrofluoric acid and nitric acid (about 1:2, number volume ) in water bath.
And the grain morphology and size distribution were observed by a transmission electron microscope (TEM) (Model: JEDL 100CXⅡ).
Fig.1 TG-DTA curve of precursor of Ag0.9Na0.1(Nb0.7Ta0.3)O3 Tab.1 The comparison of interplanar spacing of ANNT product （1） （2） （3） （4） interplanar spacing 2.7760 2.7760 2.7760 2.7760 1.9641 1.9640 1.9639 1.9640 1.6020 1.6009 1.6012 1.6015 1.3886 1.3881 1.3883 1.3884 1.2420 1.2418 1.2420 1.2419 （1）Ag0.9Na0.1(Nb0.5Ta0.5)O3 （2） Ag0.9Na0.1(Nb0.6Ta0.4)O3 （3）Ag0.9Na0.1(Nb0.7Ta0.3)O3 （4） Ag0.9Na0.1(Nb0.8Ta0.2)O3 Fig.3 TEM picture of Ag0.9Na0.1(Nb0.7Ta0.3)O3 Fig.2 XRD spectra of Ag0.9Na0.1(NbyTa1-y)O3 Fig.3 indicate that the product synthesized by the citric acid chelation method was composed of well-dispersed grain (45nm, averagely), having a relatively narrow grains size distribution and light reunition.

The high fracture toughness contributed from not only mechanism of crack deflection, crack-bridging and pull-out by a large number of fine TiB2 platelets, but also the ductile toughening result from plastic deformation of Cr-Ti-Al metallic phases.
Super high sintering temperature results in the abnormal growth of TiC-TiB2 grains, so the fracture toughness of TiC-TiB2 composites is still at a low level [1].
FESEM images and EDS results showed that a large number of randomly-orientated, fine TiB2 platelets were uniformly embedded in the irregular TiC1-x grains, and Cr metallic phases were located between TiC1-x and TiB2 crystals, whereas a few of α-Al2O3 inclusions were also observed, as shown in Fig. 2.
Fine TiC grain has certain resistance to crack propagation due to the increase of fracture surface energy and presents a classic cleavage fracture behavior, so TiC grains should be controlled in size as finely as possible.
Tailoring of phase assemblage and grain morphology of (Nd, Dy)-containing SiAlON powders prepared by combustion synthesis, Mater.