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Although the number of valence electrons of a P atom is less than that of a Fe atom, the charge densities of the Fe-P bonds (Fe1-P, Fe6-P and Fe7-P) at 0% in the P-seg1GB model were higher than those of the Fe-Fe bonds (Fe1-Fe3, Fe6-Fe3 and Fe7-Fe3) at 0% in the clean GB model.
Olson, Nature of phosphorus embrittlement of the FeΣ3[10](111) grain boundary Phys.
Yamamoto, Theoretical tensile strength of an Al grain boundary, Phys.
Mabuchi, Bond mobility mechanism in grain boundary embrittlement: First-principles tensile tests of Fe with a P-segregated Σ3 grain boundary, Phys.
Heine, Effect of impurity bonding on grain-boundary embrittlement, Phys.

Introduction Intergranular fracture is mainly induced by phosphorus (P) grain boundary segregation and loss of grain boundary cohesion [1-4].
Ohtani and McMahon [5] reported intergranular cracking occurs along prior austenite grain boundaries due to the continuity of prior austenite grain boundaries.
The samples showed fine and elongated grain structure along the RD and the prior austenite grain boundaries can no longer be recognized.
The 0.001 and 0.053 %P samples showed remarkable data scattering in absorbed energy at -100 and -150 ºC due to the increase in the number of delamination [13], where the cracks branch parallel to the longitudinal direction (//RD) of the impact test bars.
(b) The crystallographic orientations and (001) pole figures of numbered grains across the crack.

A specific single crystalline XRD method is applied on these two non-cubic phases to determine the local residual stresses in two grains on each side of a grain boundary.
Introduction Previous works over the last decade showed that a number of cast microstructure features inherently relate to the solidification path of TiAl-based (γ) alloys [1].
This new method is available for any crystalline symmetry and is applied, in this paper, to two coarse lamellar grains and adjacent lamellar grains to obtain stresses tensor in each phase and in both grains.
Optical microscopy reveals a microstructure composed of two phase γ+α2 lamellar grains with serrated grain boundaries (Fig. 1).
We can see in Figure 5 a number of spots coming from the grains in the nearby, and from γ lamellae of the grain with one of the 5 other orientations of the same grain.

Even if the number fraction of larger grains in the nanostructure is low, their volume fraction can be sufficiently high to contribute to dislocationbased plasticity in the material [1].
As already demonstrated in many metals produced by ECAP, the grain size reduction can be roughly described by the "fragmentation" of the initial grains and the creation of sub-grains having an increased amount of misorientation with increasing strain; thus leading to ultrafine grains separated by high misorientation boundaries (Fig. 1a to 1c).
Figure 1 Evolution of the microstructure with increasing number of passes (route Bc) of ECAP: (a) 1 pass, (b) 2 passes, (c) 8 passes and (d) 12 passes.
Figure 2 shows some tensile engineering stress-strain curves recorded on the ECAP-Cu samples deformed at different number of passes.
It is clear from Fig. 2a that the strength of the material increases gradually with the number of passes from 1 to 8.

The sample surface to be treated was impacted by a large number of flying balls over a short period of time.
However, the surface became stronger and harder after HESP for a great number of dislocations and micro-strain were introduced into the surface layer, so the surface layer and matrix fracture were in different deforming mode. 2.2 X-ray diffraction (XRD) analysis Results of X-ray diffraction (XRD) for both two kinds of magnesium alloy before and after HESP were demonstrated in Fig.3.
The grain sizes for different crystallographic planes of α-Mg phase in the treated surface were slightly different but all of them were smaller than 100nm, and the average grain size of α-Mg phase for magnesium alloy AZ31B and AZ91D were about 49.46nm and 52.26nm respectively, which means surface nanocrystallization was realized by HESP.
It could be observed that lots of nanometer grains resembled into a big particle and the grain size for nanocrystalline by SEM was a little larger than that obtained by XRD, which maybe caused by the limit of the max resolution ability of SEM, the results of which were in accord with those of the literature[4].
Compared to original coarse grain, the nanocrystalline or super fine grain had much higher surface activation energy and percentage of grain boundary, which meant nanocrytalline were much more apt to be corroded.

Each process was sampled five holes to determine the number of effective ear, rate of seed setting, empty and immature grain and 1000-grain weight in mature stage, and each process was also sampled 2 m2 for yield determination.
Total grain number increased with the increase of nitrogen fertilizer, and the treatment Ⅴ was the most, which had no significant differences with treatment Ⅰ (CK), Ⅳ, Ⅴ and Ⅵ, which indicated that the improvement of nitrogen application could increase the total number of solid grain but the increasing extent was not obvious after excessive nitrogen fertilization application.
Among the groups, the differences of spike weight, rate of total empty and flat grain and 1000-grain weight were not significant, which indicated that straw returning and nitrogen application amount had no significant influence on spike weight, rate of total empty and flat grain and 1000-grain weight.
With the increase of nitrogen application, Tianjing Zhao [12] thought total grain number per panicle, seed setting rate and 1000-grain weight declined gradually, while the effective panicles increased in general; Yuan cai Huang think [13] the panicles per unit area increased, but also results in a decrease in grain number per panicle, granulating rate and thousand seed weight.
This study thought the more and less amount of nitrogen both reduced effective panicles and the number of spikelets per square meters and had no impact on 1000-grain weight under the condition of straw returning while some scholars pointed that straw returning significantly reduced 1000-grain weight [8, 9], but this study found that the straw returning had no effect on 1000-grain weight. .For the studies on effects of straw returning on yield and yield components were also not the same, which may be due to the different returning way, soil, fertilization way, which need more research.

Computer simulation of the interaction of junction disclinations in nanomaterials with grain boundary vacancies A.
Atomic structure of Σ = 5 (310) tilt grain boundary in Ni viewed along the tilt axis [001].
Denote N the number of structural units belonging to a GB section of length r with the left edge on the disclination core and enumerate these units by i.
Assume that the grain size is equal to d=135 nm, then the GB length is L ≈ d/2 ≈ 67 nm.
At least two orders of magnitude increase of the effective grain boundary diffusion coefficient can be expected in both special tilt and general tilt and twist GBs in bulk nanostructured materials with the grain size d ≈ 100 - 200 nm due to disclinations with the strength about ≈ω 5°.

Acid Hydrolysis and Utilization of Distillers' Grains Yan Chen1, 2, a, Rongrong Su1, 2, b, Xiaoyan Lin1, 2, c 1School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, China 2Engineering Research Center for Biomass Materials, Ministry of Education, China a copte@163.com, b supaipai@126.com, c lxy20100205@163.com Keywords: distillers' grains, hydrolysis, reducing sugar, sulfuric acid Abstract.
Distillers' grains (DG) has high cellulose contents and is suitable for conversion to reducing sugar under dilute acid conditions.
Among the many renewable energies, biomass which distillers' grains (DG) is one kind of, is the only one which could transform directly into liquid fuel, and this kind of resource is more and more important.
The FT-IR spectrum of DG powders before and after hydrolysis display a number of absorption peaks (Fig. 6).

The slip bands have a complex internal structure formed by a number of short slip lines which become coarser after the subsequent cyclic tests.
If the slip bands are parallel to laths, the lengths of the slip bands reach the dimensions of some grains.
The bends mostly are parallel to the boundary of the former austenite grain (Fig.3).
The same was observed in the case of the steel 13X11H2B2MФ, however, plastic deformation in this steel is mainly localized on the boundaries of the former austenite grains rather than on the packets inside the grains (Fig. 2-3).
Atthe individual sites (joints of grains and packets) the localized slip bands are formed. 2.

The use of metal materials with a gradient structure [11-16], where the grain size from the coarse-grained state in the central part of the workpiece decreases to the ultra-fine-grained state on the surface, is an effective way to solve the problem of increasing the plasticity of metal products in general.
From the edge to the depth of 0.75 radius (figure 1a,b), an ultra-fine-grained structure with equiaxial grains of 200-700 nm in size prevails.
At the same time, the special state of the borders with a large number of grain boundary dislocations, necessary for the formation of special properties of the UFG structure, will be preserved.
If the set of reflexes from the polycrystalline region is uniformly distributed over the corresponding circles as in figure 1f, then the crystal lattice in the grains is oriented randomly in each grain.
Song, A good combination of strength and ductility of ultra-coarse-grained Cu-Al alloy with coarse-grained surface layer via pre-torsional treatment, Micron, 129 (2020) 102783