Search results

Applying different parameters ablative laser micromachining (power density, repetition rate, number of pulses in the same area, the overlap area microchannels), a very interesting stereometry of the surface layer steel 41Cr4 and bearing alloy was obtained.
However, alloying elements for improving mechanical properties and refining the shafts material are being added mainly due to the more uniform and fine-grained microstructure after heat treatment.

It was observed through these two tests that, increase in ball milling time after 6 hours resulted in grain size reduction.
Initially premix or hand mixed [29] where the quantity of soil was divided into ten portions and each portion was spread in a square pan (50×50 cm) then the required amount of nanomaterial was sprayed using sieve number 200 as shown in Figure 6.
However, as shown in Figure 16, the intensities of peak corresponding to reflection vary after ball-milling and become broader, indicating the decrease of grain size of kaolinite particles due to the micro strain induced peak broadening.
After 1, 2 and 6 hrs. of milling, the sample still contained the three forms of elemental powders, but with further milling (24 hrs.), peaks were reduced, showing that increasing ball mill time after 6 hrs. led to grain size reduction.

Here bioleaching of copper slag material with a copper content of about 1 % (grain size < 63 µm) and fayalite (Fe2SiO4) and magnetite (Fe3O4) as main mineral phases was tested in aerobic shake flask experiments with a mixed culture of Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Acidiphilium spp..
Additionally the number of acidophilic sulfur- and iron(II)-oxidizing bacteria was determined by MPN-cultivation [5].

Due to their unique properties these materials can be used in a large number of applications.
Estrella, Hydrogen Reduction Route towards the Production of Nano-Grained Alloys - Synthesis and Characterization of Fe2Mo Powder, PhD thesis, Sweden: Department of Material Science and Engineering, Division of Metallurgy of Royal Institute of Technology (2002) [2] M.S.

Introduction Large numbers of researches and engineering applications show that carboxylic-vinyl copolymer (PC) has not only excellent dispersibility and holding dispersibility, but also little alkali, chloride ion and good mechanical properties.
HC is advantage to disperse cement particles and increase the number of active hydrating points in initial several minutes.
From fig. b, the CH, which is hexagonal flake, is well crystallized, and the structure of cement paste is close-grained.

While most relate this improvement to electronic effects, it has been pointed out that the addition of Ag can modify the grain sizes of the TiO2, so increasing the surface area and hence also the photoactivity [2].
In the non-photocatalysis pipe system (Table 1), the bacterial count on glass fiber (the number of 4, 5, 6 and 7 shown in Fig. 1) was much smaller than that on filters (the number of 8 and 9 shown in Fig. 1).

Introduction The titanium dioxide (TiO2) has been considered as a promising material recently which has a large number of applications such as the photocatalyst [1] and diluted magnetic semiconductor (DMS) devices [2-4] in spintronics.
The mean grain sizes of the samples were evaluated by Scherrer’s formula with the A (101) reflection and the results are summarized in Figure 2.
This makes us interpret the decrease of Hc when the temperature falls: The free carriers and defects are produced by heat exciting to a large degree, and the number of them increases exponentially with temperature (N ∝ e-D / kB).

Since then, this effect has been studied many times in different materials, and it is generally recognized that the difference, between the forward and the reverse mechanical responses, can be attributed to the interaction of the dislocations with the microstructure, mainly precipitates, grain boundaries or elastic second phase particles such as those found in metal matrix composites or intermetallics [2, 3].
will increase the number of stored dislocation and thus the internal stress.
Moreover, in the case of the peak aged material, it has been shown that the precipitates are still shearable by the dislocations [5] and thus the number of dislocation loops formed around the precipitates is very low.

Introduction Ionic Soil Stabilizer(referred to as ISS) is a strong ion by a combination of several water-soluble chemical substance, applied to clay content in the grain group of more than 25% of all soil types.
Table 1 Basic properties of the red clay natural water content ω[%] Natural density γ[g·cm-3] proportion △s liquid limit WL[%] plastic limit WP[%] plastic index IP[%] free swelling ratio Fs[%] 24.81 1.92 2.76 57.86 24.27 33.59 60 Curing materials Ionic Soil Stabilizer (referred to as ISS) is a kind of mixed liquid that contains a number of strong ionic compounds, and it is brown-black water-soluble liquid.
In the dynamic triaxial tests, when the confining pressure increases, due to closer contact between soil particles, pore reduction, so wave energy loss in the dissemination process will be reduced, the corresponding number of parameters characterize the energy loss is also damping ratio reduced accordingly.

Experimental The concrete was mixed by 42.5 ordinary Portland cement, continuous grading crushed stone with grain size 5-20 mm, natural river sand with fineness modulus 3.3, water reducer, steel fiber and polypropylene fiber.
With the increase of freeze-thaw number, the hybrid fiber concrete test specimen of the flexural strength decreases.
Fig. 2 Changes of flexural strength of FHPC with mass content of polypropylene fiber and fraction of steel fiber by volume On the basis of the steel fiber volume rate is 1%, with the increase of content of the polypropylene, the specimens can achieve the freeze-thaw number are on the rise.