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As a result, we have achieved a higher VOC of 0.725 V, confirming that the sintering behavior (grain growth and/or necking of grains) influenced largely the characteristics of DSSCs.
It also indicates the promotion of grain growth.
As to the photocurrent, the grain growth is not always favorable for the cells because the amount of adsorbed dye is largely decreased.
In the films heated at the higher temperature, the grain growth proceeded with the necked particles approximately 100 nm in size.
In contrast, VOC increased with the heating temperature probably because of the smaller number of recombination sites on the surface or at the grain boundaries.

If the numbers of grain boundaries are too much, the corrosion of the alloys is severe.
Nd showed a significant grain refinement function on the alloys.
With the increment of Nd content, the fraction of the second phases became higher, the number of the grain boundary is increased. 2.
The result was directly related to the microstructure of alloys, which was attributed to the combined contributions of the better uniform microstructure, the lower fraction of second phases and the less number of grain boundary. 3.
Compared with the MZC2.0Nd alloy, the increases of both the fraction of second phases and the number of grain boundary were observed in the MZC3.0Nd alloy.

A number of efforts have been made by researchers in order to understand the nature of the giant dielectric response in CCTO [1-4,6-7].
IBLC model suggests that the desirable results for high dielectric constant and low dielectric loss could be achieved for CCTO with larger grains and highly resistive grain boundaries. [6] Therefore, focusing the research on microstructure and electrical properties of the grain and grain boundary has become an important method in exploring dielectric properties of CCTO.
Sample sintered at T=1050oC consisted few large grains embedded in small grain of CCTO, indicating the beginning of the grain growth process during sintering [12].
Biggest grain size was observed when the samples were sintered at 1100oC.
The values of grain boundary resistivity, ρgb and grain conductivity, σg are tabulated in Table 2.

A JMAK based model was applied to describe the nucleation grain growth process.
(a) Recrystallized fraction and (b) average grain size versus annealing time at 700°C.
After nucleation, each grain grows freely until it meets another growing core [8,13].
Grain growth rate (G) as a function of the annealing time (t).
Acknowledgements The authors acknowledge FAPEMIG (TEC process number APQ-3318-5.07/07) and CNPq (process number 476377/2007-2) for the financial support for this research and the contribution of Usiminas for this publication.

Band-like features, with a thickness in the order of a micrometer, across the grain were identified in Fig. 3(a).
Although, the number of reports on polycrystals is limited, to clarify the dependence of deformation twinning on grain orientation in polycrystalline Fe–Si alloys, the crystal orientations with deformation twins were analyzed.
Grain orientation did not play an important role in determining the occurrence of deformation twinning
Acknowledgements This study was financially supported by JSPS KAKENHI Grant Number 23760700 and 22nd Research Promotion Grant from The Iron and Steel Institute of Japan.
Hull, Effect of grain size and temperature on slip, twinning and fracture in 3% silicon iron, Acta Metall. 9 (1961) 191–204

Al3Zr particles which are coherent with the matrix would inhibit the movement of dislocation induced by stress and also the migration of sub-grain boundary and grain boundary induced by thermal activation.
In these conditions, unshearable Al3Zr particles contribute to the piled-up dislocations at the grain boundary of the occurrence of the strain induced grain boundary migration during recrystallization.
The results show that a large number of Al3Zr particles had been precipitated in the alloy (Fig. 1 a and c).
After the D treatment, a large number of small size and dispersed Al3Zr particles were precipitated.
A greater number of subgrains cause the alloy grain size to decrease.

Electrochemical Characterization of Supercapacitor Electrodes Prepared by Activation of Green Monoliths Consist of Self-Adhesive Carbon Grains and Lignin Roslinda Zulkifli1,2,a*, Mohamad Deraman2,b, Rusli Daik1,c, Maria Muhammad Ishak2,d, Najah Syahirah Mohd Nor2,e, Mohamad Redwani Mohd Jasni2,f, Sepideh Soltaninejad1,2,g and Mohd Suleman2,h 1School of Chemical Science and Food Technology/2School of Applied Physics, Faculty of Science and Technology, University Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia *Corresponding Author: alindatyco@yahoo.com bmadra@ukm.edu.my/bmderaman113@gmail.com, crusli@ukm.edu.my, dmaria.ishak86@gmail.com, enajahsyahirah@siswa.ukm.edu.my, fmohamadredwani@gmail.com, gsepidehsoltaninejad2012@gmail.com, hmdslmn@gmail.com Keywords: Self-adhesive carbon grains, Activated carbon monoliths, Lignin, Supercapacitor electrode.
Abstract: Self-adhesive carbon grains (SACGs) and lignin were produced from fibres of oil palm empty fruit bunches by a low carbonization temperature and chemical treatment methods, respectively.
This report demonstrates the effect of lignin addition to green monoliths (GMs) of self-adhesive carbon grains (SACGs) on the performance of supercapacitor cells fabricated using the electrodes prepared from the GMs.
It can be noticed that of all the electrodes, the ACM05 electrodes based cell offers maximum charge and discharge times which can be accounted for the higher number of electrons and electrolyte ions participating in the charge and discharge processes.
Ismail, Young modulus of carbon from self- adhesive carbon grain of oil palm bunches, J.

By severe plastic deformation of metals, an ultra fine grain size can be obtained.
The specimens after ECAP showed a very fine grain size, a decrease of <100> // ND, and an increase of <111> // ND textures.
The as-deformed metals retained high dislocation densities, a large number of low angle sub-grain boundaries, and showed being in non-equilibrium configurations [7].
The grain of initial Al sheet exhibited an equi-axial, uniform, and coarse structure.
The grains were elongated, having an angle of 15 - 30 degrees to the ECAPed out direction.

The deformed grains either contain homogeneously distributed subgrains of similar size, or heterogeneously distributed small subgrains at grain boundaries (mantle subgrains) and relatively large subgrains in the core of grains (core subgrains).
Substructured and Subgrain Free Grain Fraction.
To avoid confusion, we will use the terms subgrain free and substructured grains rather than recrystallised and deformed grains.
Still, the AMG of a subgrain free grain will be typically smaller than ~1° and therefore the cut off AMG to distinguish a subgrain free grain from a substructured grain is chosen to be 1°.
The number of domains on which the average is based is given between brackets. (*) size without distinction between core and mantle.

The grain size decreased with increasing strain rates at 750k. 1.
The microstructure consists of elongated grains with serrations developed in the grain boundaries and newly formed equiaxed grains of different sizes, indicating dynamic recrystallizatioin (DRC) occurred during hot compression deformation at strain rate of 0.01s-1 (Fig3(a)).
The coarsening of precipitation phases at grain boundary could pin the grain boundary, and prevent it from fast migration, so both the newly formed recrystallized grain and old grain would not grow very fast.
That is why the grain size decreased with increasing temperature at 750k.
Acknowledgement It is a project supported by natural science foundation of shanxi province China (project number: 2009011028-1; 2011011021-1).