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This method provides the greatest number of information when testing the stents' surface and it is well applicable for the analysis of surface alterations caused by different specific tests, e.g. fatigue test.
The recoil values of the Guidant MultiLink Zeta, the Cordis Sonic and the Boston Scientific LP stents at the proximal (P), the medial (M) and the distal (D) cross-sections After having expanded the balloon the number of surface failures is increased, in strut bends when the material has had bigger use, the grains slip, and slip lines and grain boundaries occur.
The most frequent surface failures of the coronary stents after the expansion: a) slip lines, slip bands and grain boundaries, b, c) rough surface Conclusions Two kinds of raw materials are used for coronary stents: austenitic corrosion resistance steels (316L, 316LVM - 85%) and cobalt-chromium alloys (L605, MP35N - 15%).
Small holes, smaller or bigger inclusions and scratches, moreover slip lines, grain boundaries and rough surface caused by pliable metamorphosis are the most frequent failures on the surface of the stents.

It can be estimated that the number of applications containing optics or optical systems will further increase within the next years.
Beside its low binder content, the material also features a very fine grained structure with grains of less than 0.2 µm in diameter.
Within the vitrified bond, diamonds grains with an average diameter of 15-20 µm are carried.
Second, an entire wafer mould featuring about 150 single cavities was machined to prove the capabilities of the kinematics over a larger number of cavities.
Heinzel, Dressing of coarse-grained diamond wheels for ductile machining of brittle materials, Towards Synthesis of Micro-/Nanosystems B7 (2007) 305-307

Black areas on the grain boundaries are () phase.
Some needles can be seen inside the grains.
The black areas on the grain boundaries are secondary phase ().
This is because the cast alloys contain a large number of phase which has high hardness and very fragile, which may cause wear behaviors becoming more deterioration to surfaces of the alloys by torning.
On the other hand, during sliding of metallic materials, a number of thermal and thermo mechanical processes occurred at the contacting surfaces [13–14].

The reduction of arable land, shortage of water resources, climate change and other factors has brought increasingly prominent effect on grain production.
（4） In the formula, n was sample number.
Sample number n was 9.
An analysis on the influential factors of grain production per hm2 and grain loss evaluation in shanxi province.
Estimation of cropped area and grain yield of rice using remote sensing data.

Calcium silicate body can be characterized as non-cement based fine grained concrete, however, with considerably higher water absorbing capacity compared to standard concrete: ca 12-14% (fine aggregate bonded by hydration products of lime).
Rebound numbers are higher on concrete saturated with water than those measured on dried concrete.
Test results: Table 2 gives results of the tests (rebound number) for observation influence of moisture and temperature and difference in per-cent for the rebound numbers DRW and DRT.
Difference of rebound numbers with various moisture content DRW is related to the rebound numbers measured on dried specimens and the difference of rebound numbers at various temperature and moisture content (W=2% by mass and specimens saturated with water) DRT is related to rebound numbers measured with specimens at the temperature of +20°C.
Figure 1 Influence of moisture content of calcium silicate body on rebound number Figure 2.

The temperature conditions of superplastic deformation of TiAl are largely determined by the grain size [20].
In all cases, the bond-line microstructures consisted mainly of fine (10-20 µm) twin related grains.
A bonding time of 10 h was too long leading to an excessive grain growth at the bond interface.
After PBHT a coarse-grained microstructure was obtained.
Multilayer nanostructured thin films with nanometric period due to the high number of interfaces have increased diffusivity (self-propagation exothermic formation reactions of Ti with Al, where Ti-Ti and Al-Al bonds change to Ti-Al [46]).

It leads to a number of negative consequences in the subsequent forming: distortion and dimensions alteration of parts, limitation of formability, metal losses due to overestimation of thickness and dimensions of blanks, weight increase of the construction.
The exception is a sample from V-1461 alloy with thickness 39.7 mm, which is recrystallized with extra large and strongly elongated grains.
Summary The main characteristic inherent to both the first-generation aluminum-lithium alloys and the subsequent ones is a pronounced anisotropy of the properties, which can lead to a number of negative consequences: distortion and dimensions alteration of parts, limitation of formability, metal losses due to overestimation of thickness and dimensions of blanks, weight increase of the construction.
The formation of a homogeneous structure in plates and sheets with an equiprobable grain distribution over crystallographic orientations (weakening or lack of texture) is one of the solutions for this problem which leads to reduction of anisotropy.

To prepare the GMC materials, the �spodumene and a soda-lime commercial glass were grounded to grain sizes smaller than 1µm and 1.7µm, respectively, followed by planetary milling within isopropanol.
If the number of dispersed particles is larger than the number of glass matrix particles, aggregates of the former cannot be avoided.
An equal number of glass matrix particles, of average diameter Dm, and �-spodumene particles, with average diameter Dp, is reached when the particle volume fraction is �p=1/[1+(Dm/Dp)3 ].
To avoid aggregation in the 25 wt.% GMC materials a different diameter ratio should be used (Dm/Dp ~ 1.44). 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0.0 0.2 0.4 0.6 0.8 1.0 Particles Volume Fraction Grain Diameter Ratio: Dm/Dp 0.01 0.1 0.01 0.1 1 10 100 1000 V700H0.5 C10700H0.5 C25700H0.5 Intensity (cm-1 ) Q (Å -1 ) Fig. 2.
Volume fraction of dispersed phase particle, for the case of equal number of matrix grains, of average diameter Dm, and dispersed particles, with average diameter Dp, as a function of Dm/Dp.

The application TioCem or TioCem White photoactive cements using proprietary TX Active technology created by the company Italcementi (nowadays part of the HeidelbergCement Group) is the only example of its use, at a reduced, pilot application scope on a smaller number of test buildings.
It is clear that the photocatalyst is not covering every grain or even the whole surface of the sand grains, however they are sufficiently covered to enable the self-cleaning photocatalytic effect, as has been shown through repeated measurements of the reduction in NOx carried out by the Institute of Inorganic chemistry of the Czech Academy of Sciences (see section 3.2 above).
Fig. 5, top left, then demonstrates that during the plaster preparation process most of the photocatalyst remained attached to the quartz sand grains, but can also partially be found outside of these.
Fig. 6 The number of colonies of Bacillus subtilis (CFUs) In our case we quantified the antibacterial photocatalytic activity based on colony creation of the microorganism Bacillus subtilis.
The graph depicts the number of Bacillus subtilis colonies which grew on the samples: 1) without photocatalytic function, exposed to UV radiation for a period of 4 hours, 2) with photocatalytic function, but without coming into contact with UV light and 3) with photocatalytic function, exposed to a UV source for a period of 4 hours.

Number Type Size Initial packing density [g/cm3] Related porosity Source A Flakes Several mm 1.31 41% Source B Powder 0.1 – 1 mm 1.44 45% Source C Powder 0.1 – 2 mm 1.50 47% FAU ref.
Number Power (exp) [kW] Tcrucible (exp) [°C] Tcrucible (sim) [°C] Tseed (sim) [°C] Tgradient (sim) [°C/cm] Source A 10.25 2030 2035 2114 7.4 Source B 11 2095 2085 2166 6.3 Source C 10.5 2040 2048 2126 6.5 FAU ref. 10.25 2026 2101 6.4 Table 3.
Number Power (exp) [kW] Tcrucible (exp) [°C] Tcrucible (sim) [°C] Tseed (sim) [°C] Tgradient (sim) [°C/cm] Source A 10.25 2030 2035 2114 7.4 Source B 10.25 2026 2101 6.4 Source C 10.25 2028 2104 6.6 FAU ref. 10.25 2026 2101 6.4 Altogether, the chosen hot zone design is quite insensitive to the applied SiC source material (type of powder or coarse grain flakes).
Number Power [kW] Tcrucible (sim) [°C] Tcrystal (sim) [°C] Tgradient (sim) [°C/cm] Source A 10.25 1998 2106 5.7 Source B 11 2047 2171 5.9 Source C 10.5 2019 2127 4.9 Mass Transport Calculation.
Conclusions Although all three SiC source materials led to almost similar thermal boundary conditions in the initial growth stage, the axial temperature gradient inside the gas room is higher in case of the coarse grain source A compared to the sources B and C.