Search results

In a bright-field image mode, we could observe both the grain boundary and loop-shaped dislocations.
In the case of the apatite fibres heated at 1200˚C for 1 h, a large number of angular voids were present in the fibres, together with some strains and grain boundaries.
We confirm that this contour arise due to grain boundary in the fibres by tilting experiments.
GB: grain boundary showed the HOLZ of apatite crystals (Fig. 6 (e)).
(a, b, c) grain boundary, (d, e) voids; (a, d) bright-, (b) dark-field images, (c, e) SAED pattern.

The compilation process of bidding price control The bill of quantities of coarse grain type asphalt concrete in a highway pavement engineering is listed in table 1.We will illustrate the necessary steps which the preparation of the bidding price control has, under the bill of quantities valuation mode through the compilation process of coarse grain type asphalt concrete’s comprehensive unit price.
Table 1 Road engineering bill of quantities Contract period number: bid highway 01 Monetary unit: (CNY) Item no Item name  Unit of measurement Quantity Unit price Total price 309-3 Coarse grain type asphalt concrete (80 mm thick) m2 180000 Compilation of the bidding price control, on the basis of the quantity of the budget according to the requirement of specific site conditions and time limit for a project, feasible construction scheme, and considering the necessary special engineering measures, according to the project and the amount of the bill of quantities, calculate the cost of the bill of quantities (mainly building installation project cost).
Asphalt concrete mixing plant is located in the middle of the pile number, near distance proposed road of 0.8 km; 15 t dump truck used to transport for mixture is equipped with a number of vehicles
Table 2 Detailed list including quotas and quota adjustment status Item no Item name Project quota Project quota name Quoa unit Quota engineerig quantity Quota adjustment 309-3 Coarse grain type asphalt concrete (80mmthick) 2-2-11-6 Mix asphalt concrete mixture(320t/h) 1000m³ 14.4 2-2-13-21 Within 15 t dump trucks transport the first 1 km 1000m³ 14.4 +22×3 2-2-14-27 Within 320 t/h mechanical paving asphalt 1000m³ 14.4 2-2-15-6 Asphalt mixture mixing plant, Installation and removal (320 t/h) 1 0.42 Calculation shows: (1)The fixed quantity of asphalt mixture mixing plant(320 t/h) was calculated by the coarse grain type asphalt mixture proportion of the total number of asphalt mixture, (2)Fixed quantity of asphalt concrete mixing, transportation, paving is calculated by formula 180000 ×0.08/1000 = 14.4.
Table 3 Bill of quantities bidding price control Contract period number: Bid highway 01 Monetary unit:( CNY ) Bill Chapter 300 Pavement Specific item no Specific item name Unit of measurement Quantity Unit price Total price 309-3 Coarse grain type asphalt concrete -a 80 mm thick m2 180000.000 56.02 10083600 Calculate total amount of the bidding price control.

Carbon and boron were mainly considered to strengthen grain boundaries formed during single crystal casting of complex shaped components.
However, it is susceptible to grain defects during single crystal casting because of their geometrical complexity [2].
Grain boundary strengthening by addition of minor elements, such as C, B, Hf, and Zr, has been a considerable research subject to overcome the grain problem in the air-cooled single crystal turbine blades and vanes [3].
Carbon and boron were mainly considered to strengthen grain boundaries formed during single crystal casting.
Also, number of dendritic interface increased with increasing B addition.

The effect might change the grinding mode of the diamond grain micro-blade in the grinding process, thus to affect the grinding efficiency and the machining quality.
Testing conditions:RFS100 Raman Spectrophotometer manufactured by BRUKER; wave number range: 50~3500cm -1; resolution: 2 cm -1, scanning times: 500; laser power: 300mW.
It was showed by the comparison between the above four diagrams that there was a waving peak in the wave number range about 900cm -1 after polishing or applying alcohol-oleyl to the ceramic grinding surface.
It can be concluded from the above testing that as for the alcohol grinding fluid, some reaction led to increased resistance to grinding grains in the grinding process, hence to cause increase grinding efficiency when grinding silicon nitride ceramics.
Wave peak changes could be showed by the changes of resistance to the grinding grain in the grinding process.

In many cases, natural sintering is unsuitable due to the difficulty in controlling grain growth in the temperature regimes needed for full densification.
A reverse-strike co-precipitation was used in one case, since it is able to assure a highly-homogeneous, fine-grained product [12,13].
XRD pattern of powder R treated at 1290°C for 1, 5,15 minutes soaking time (Y=YAG, α=α-Al2O3) (a) (b) Figure 2: Dilatometric (a) and derivative (b) curves of un-treated powder R sintered at 1600°C for 3 h (solid line) and of milled powder R (dotted line) sintered at 1420°C for 2h The lowering of the above characteristic temperatures was not imputable to pollution due to extensive milling, as it was demonstrated by a statistic observation of a large number of grain boundaries of sintered materials performed by High-Resolution Transmission Electron Microscope (HR-TEM, Jeol 2010FEG, Figure 3): in fact, no relevant impurities nor silica-based glass were observed at the interfaces.
The microstructure was highly homogeneous with a mean size of both α-alumina and YAG grains of about 300 nm. 2.
The powder pre-treated at 1100°C, which contains a higher amount of α-Al2O3, yielded a homogenous and very fine microstructure made of grains in the range 200-400 nm in contrast with the 1000°C pre-treated powder in which a more relevant αalumina grain growth was observed.

Two groups of experimental scheme were carried on by using fine grain cast iron diamond wheel and nozzle-type ELID grinding apparatus.
In this work, experimental investigations on nozzle-type ELID grinding of cemented carbides were conducted by using fine grain cast iron diamond wheel and nozzle-type ELID grinding apparatus.
By using this method, it avoids installing the electrodes on the machining region, saves the occupation space of the electrodes and realizes weak electrolysis and continuous dressing of fine grain metal-bonded wheels.
It is mainly because the speed of electrolysis reaction and oxide film generation become faster and the thickness of oxide film increase at a higher pulse frequency, which decreases protrusion height of the abrasives and the grain number involving in the grinding, and results in the increase of the grinding force.
Acknowledgements This research is sponsored by the NSFC (Grant No. 50975084 and No. 50811120105) and the National Key Technology R&D Program in the 11th Five Year Plan of China (Project number 2007BAF29B03).

It can be seen that the surface structure of the thin films are notably different, the grain size and the grain shape vary significantly between the samples.
The AFM images show that a decrease in number of grains is found on the thin film surface along the deposition power increasing, which indicate that the grain size becomes progressively bigger.
When the film is deposited at 900W, a large number of cauliflower-like grains are observed, the size nearly 300nm and the surface roughness is ~7nm.
The AFM images showed the grain size and voids of the films increase with deposition power increasing.
The grain size of thin film deposited at 100W and 900W are about 100nm and 300nm, respectively.

This forms nodules that grow into the original parent grains.
• The continuous size distribution of the particles is divided into a large number of size classes
• The number of new particles in each time step is calculated using classical nucleation theory.
The Tu and Turnbull model predicts that the discontinuous nucleation rate is given by the grain boundary nucleation rate multiplied by a probability factor that a grain boundary precipitate will develop into a discontinuous nodule.
(a) Continuous precipitation only, particle length and number density for AZ91 aged at 200�C (data from [1]).

However, the grains remain relatively small, with irregular shapes and intergranular spaces still visible, suggesting limited grain growth at this temperature as revealed in Fig. 1b.
The porosity decreases as the particles density, and grains appear to expand.
At elevated temperatures, smaller particles merge to form larger grains, which reduces the overall surface area due to a decrease in the number of fine particles.
As the sintering temperature increases, improved crystallinity and grain growth reduce the number of defect states and lattice distortions, resulting in a widening of the bandgap [50-53].
The grains were also less than 100 microns as per the SEM (Fig. 1d).

It can be seen that the grain size and its distribution were greatly influenced by the synthesis time duration where the grain size increased when the time duration increased.
Grain size and its distribution greatly affected the surface area and grain boundaries of the nanostructured FTO thin film.
As lesser grain boundaries can cause larger conductivity and higher electron density, the lowest grain boundaries can be obtained by having the largest grain distribution.
However, there were numbers of irregular grains, compact structures and different shapes at three different time duration.
In addition, the transmittance mainly depended on the film thickness, grain size, grain distribution and morphological structure.