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Standard quartz sand with maximum grain size of 2.5 mm was used as aggregate in order to prepare mortars.
However, if we compare differential intruded volume which refers to the number of pores, it is obvious that most of the pores in alkali-activated slag is smaller than 10 nm whereas pores in cement matrix are split in two regions – one below 10 nm and the other between 20 and 300 nm of pore size (Fig. 1B).
Bernal et al. [19] used high-resolution X-ray fluorescence microscopy for the characterization of distinct particles embedded in blast furnace slag grains and proved the existence of metallic iron nanoparticles which do not take part in alkaline activation of slag.
AAS matrix also contains a large number of micropores containing pore solution of very soluble and mobile hydrated Na+ ions.

In any case, it is necessary to sensitively modify the method of selecting the place of taking samples from individual structural elements and their number with respect to the character of the evaluated structure.
A quite fundamental disadvantage of this cement is, however, the fact that the occurring hydration products are unstable under common atmospheric conditions and their “conversion” occurs (great attention is paid to this issue in a number of publications; therefore it is not described in detail here).
At the approximate temperature range 700°C to 820°C, a decomposition of the fine-grain calcium carbonate (i.e. vaterite and aragonite) occurs.
At the temperature interval of ca. 820°C to 940°C, a dissociation of the coarse-grain calcium carbonate (mainly calcite) occurs.

The hydration of magnesia grains is one important issue as it leads to local volume expansion, which induces internal stresses and crack inceptions [8].
For the digital image number i, comprising a series of Q4 elements (Fig. 3a), where each one is firstly assigned to a group.
Finally, the total crack network length c, the surface crack density χ (χ = c/SROI, where SROI is the ROI surface) and the average opening displacement ∆u are obtained by cumulation over the number of elements containing cracks.
As the hydration of MgO particles initiates at the grain boundaries of the polycrystalline material, it is limited to a fine surrounding layer.

A number of rapid prototyping techniques are available, which differ in a material to be used and a way to form an article.
SLM-based manufacturing of a high-quality article is associated with a number of complex and ambivalent physical phenomena despite advantages of additive technologies.
Materials and Methods A powdered copper material with flake-shaped particles was used in experiments; Table 1 gives its grain size distribution.
Table 1 – Grain size distribution, % dimensions of particles <100 [µm] 99.5-100 <71 [µm] 90-100 <45 [µm] 65-80 Non-contact optic microscope LEXT OLS 4100 (OLYMPUS) was employed to examine roughness of the surface layer in a 3D system of coordinates, Fig. 1.

Further, if these alloy are maintained at higher temperature also for short periods of time, precipitation of secondary phases (Mg2Si particles at grain boundary) occurs leading to improved mechanical properties (aging phenomenon); an excessive exposition to these level of temperature has the opposite effect since precipitates coalesce into larger particles, causing a reduction of the alloy properties (overaging) [8-9].
Such a behaviour is strictly related to the aging phenomenon, which is characterised by the precipitation of intermetallic phases (Mg2Si) at grain boundaries [8-9]; this means that the more slowly the test is performed, the longer the time exposition to high temperature is (and consequently the greater the aging effect).
In order to highlight the effects of the heating and cycle time, in Fig. 6-a the thickness distributions concerning HydroForming tests at the temperature of 200°C, characterised by different values of the heating time (the number which follows the letter H) and the cycle time (the number which follows letter R) have been reported.

Building materials based on magnesium binders, called magnolites, are characterised by a number of valuable properties that are essential for creating environmentally friendly materials [7]: – high compressive strength in the early curing stage, with flexural strength that is 3–5 times higher than that of traditional concrete; – fire safety – with sufficient structural thickness, magnolite structures can withstand a category 5 fire without material destruction or the release of carcinogenic substances; – low dielectric permittivity and electrical conductivity – magnolites are used to protect against electromagnetic radiation, their surfaces do not accumulate static charge, which eliminates the risk of sparks; – resistance to weather conditions, as well as to oils, petroleum products, and salts; – fungicidal and bactericidal properties, which prevent the growth of fungi and bacteria, while its bitter-salty taste deters insects and rodents; – aesthetic versatility – capable of imitating
Ochre consists of a small amount of very fine-crystalline anisotropic brownish mass and about 10 mass % quartz grains.
When ground, the rock disintegrates into smaller aggregates with grain sizes of less than one micron; – synthetic inorganic pigments produced in China: iron oxide yellow 420-1-68; iron oxide green 5605-1; iron oxide red 120-1. 2) Organic pigments developed at the Department of Organic Synthesis and Nanotechnologies of NTU "KhPI": – daylight fluorescent pigment based on polyester resin DDP-l (lemon color); – daylight fluorescent pigment based on melamine-toluenesulfonamide resin DDP-z (green color); – daylight fluorescent pigment based on melamine-toluenesulfonamide resin DDP-pch (orange-red color).
Results of physical and mechanical tests of coloured dolomite brick samples Pigment Pigment content, wt. % Water absorption, % Compressive strength (28 days), MPa Frost resistance number of cycles, not less than Without pigment – 11.57 28 25 Inorganic pigments Ochre 4 14.13 26.0 25 Yellow 2 13.01 27.0 25 Green 2 15.5 26.4 25 Red 2 15.11 27.4 25 Organic pigments DDP-л 4 10.52 26.4 25 DDP-z 4 9.4 26.0 25 DDP-pch 4 9.56 27.5 25 3 Conclusions Thus, the research demonstrated that it is possible to use natural bischofite brine from the Zaturynsky deposit, a side-stream of gas production in Poltava Oblast, as a mixing agent for the production of dolomite-based finishing binders.

The microstructure analysis showed that the low strengths of T6 A356 alloy should be at least attributed to the absence of the magnesium-based intermetallic phase, coarse grain structure and the presence of porosity, which resulted from the HPDC process, MIG welding and thermal treatment.
Therefore, the high vacuum (V-HPDC) process, advances the die casting process and makes it more competitive for mass production of structural automotive components with enhanced properties and significantly reduced number of defects [2-5].
Based on the optical microstructural analyses, the grain size and silicon particle in the fusion zone (ER4043) were finer than those base metal, which resulted in an increase in strengths of the fusion zone of the filler alloy ER 4043.

Countsum / Scovered: It’s the number of sensor nodes in unit area.
When the number of node is more than two at the set of the Sch, the node is a boundary point.
When the number of node is more than two at the set of Sch, the node is a boundary point.
The number of nodes deployed in every experiment is 10, 20, 40, 80 respectively.
[2] Elson J, Girod L, Estrin D: Fine-grained network time synchronization using reference broadcasts.

Use block molding, vibrating close-grained, after 24h bosses.
The main purpose of this study is to establish the surplus compressive strength and fatigue cyclic number relationship (except for special instructions,this article mentioned in the residual strength shall mean residual static load strength).
Table 3 Corrosion residual strength of concrete Numbers number specimens 2 specimens 3 specimens 1 AVG Not corrosion 7000 33．6 29．5 29．8 31．0 sodium 6000 29．0 30．9 25．9 28．6 Data processing Because by fatigue corrode the influencing factors of concrete is more, Formula should not too complicated, minimize parameters to ensure the accuracy of the calculation, So this article selects the residual strength model formula is [7]: (1) In the type, is fatigue times of concrete fatigue residual strength; is fatigue maximum stress;is fatigue life; is fatigue stress level for relevant constant.
According to the formula (2) to (3),We can be calculated when the number of different fatigue residual strength of concrete.
In practical engineering, Sulfuric acid root ion on concrete corrosion should not ignore, should consider the corresponding protective measures, to ensure the project can achieve the desired use fixed number of year.

Number: 1.0976.
Pure titanium powder with the ~70 µm grain size was blown into the melted substrate under the angle of 45° using argon as carrier gas.
(Increasing sequence numbers 4,6,8,10), the length of the scale bars are 2 mm Figure 4.
Light microscopy images of sample number 4b/3 with the hardness results Figure 5.
Three different structures can be distinguished in both pictures: a homogeneous solid-solution type marked with number 3, a dark fine globular or equiaxial dendrite with high Ti content marked with number 2, and a two phase structure most likely eutectic or eutectoid marked with number 1.