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In addition, the porosity and tortuosity are the two most significant factors affecting the chloride ions penetration for alkali-activated fly ash concrete.
Mechanical and microstructural properties of alkali-activated fly ash geopolymers.
Effects of Dosage and Modulus Ratio of Alkali-Activated Solution on the Properties of Slag Mortars.
Setting and mechanical properties of alkali-activated fly ash/slag concrete manufactured at room temperature.
Strength and shrinkage properties of alkali-activated slag concrete containing porous coarse aggregate.

Building's being used water is the biggest factor affecting the surrounding natural world, building size transformation model .This transformation to reduce the adverse effects of construction on the environment has an important significance.
Adding to poor insulation design, existing heating system under poor adjustment and other factors, so it cause indoor climate to be vulnerable to outside influence, the summer heat and winter cold, is not conducive to building energy efficiency, and daily use difficult.
In a certain light at the same time with considerable thermal insulation properties besides certain light transmittance.
Use mechanical devices to blast air into cental air , take away heat by the flowing air to enhance the ability of roof insulation.

Further more, cracks will cause housing leakage and affect the aesthetics of buildings.
Causes of crack formation is complex, crack damage degree is not only relative to crack size but also relative to crack property and structure function requirement.
As a result, we should ascertain exact reason of cracking, treat with factors that causing crack, and take different proper measure to different kinds of building crack.
Row Material and Environment Factor.
For those cracks that are not load crack, though the crack will not affect structure safe, but must be take into account also because house are all-important personal estate and crack may affect beauty and function of building.

The results allow to optimize preparation conditions for nanocrystallizing Al-based alloys with enhanced mechanical properties.
Introduction The fcc Al nanocrystals precipitated in amorphous Al-based alloys cause the enhancement of mechanical properties [1].
This interaction is not affected by the inner side 4f states which are screened by 5s and 5p electrons.
Summary The detailed analysis of electron transport properties of numerous alloys from the Al-Y-Ni, Al-Y-Cu families shows that the strong Al-TM and Al-Y bonds are formed by filling the 3d and 4d states of TM and Y atoms by the 3s and 3p electrons from Al.
The above experimentally established interplay between the chemical composition and nanocrystallization of Al base alloys allows to taylor alloys with requested superior mechanical properties.

Introduction Duplex stainless steels (DSSs) consisting of a dual structure of austenite (g) + ferrite (a) possess the superior mechanical and corrosion properties, and have been applied to various industrial fields such as petrochemical, power and seawater desalination plants.
On the other hand, during fusion welding, DSSs undergo the complex microstructural change and phase transformation affecting the a/g phase balance due to the weld thermal cycle [3,4].
Comparing the hardening behaviour in each region of weld (WM, HAZ and BM), the major factor affecting the progression of 475˚C embrittlement was clarified and the mechanism of 475˚C embrittlement in DSS weld was discussed coupled with the thermodynamical consideration.
(a) Base metal (b) Weld metal (c) Heat affected zone Fig.8.
Mcpherson, Y.Li and T.N.Baker: “Microstructure and Properties of As Welded Duplex Stainless Steel”, Sci. & Technol.

Introduction Wrought aluminium alloys have a number of desirable properties such as low density, high specific strength and excellent formability that make them particularly attractive in various applications such as aviation and automotive [1].
In this article, the effect of combined electromagnetic and ultrasonic fields on the grain refinement of molten AA7449 has been investigated and the resulting mechanical properties evaluated and compared with AA5754 [13].
The mechanical properties resulting from each technique were evaluated and compared.
The mechanical properties (i.e.
Mondolfo, Aluminium alloys: structure and properties, Boston: Butter- worth, 1976

Introduction Practically on every object in our surroundings is affected by number of negative factors, which are for example impacts of snow, wind or freeze.
In the past was wetness in masonry manually decreased by mechanical methods.
For testing of properties of injection gels were chosen following laboratory exams.
Addition of injection gels improved all of tested properties in all tested materials.
[4] ČSN 73 1357: Determination of capillary properties of aerated concrete

Parameter K defines the slope of a sudden drop on load vs. diameter reduction diagram and it is often denoted as “accelerating factor”.
Table 1 Chemical composition of tested steel (in weight %) C Si Mn P S Cr Mo Ni Cu Al 0.22 0.21 0.86 0.018 0.011 0.42 0.83 0.92 0.05 0.015 Static mechanical properties of steel determined by tension on a smooth specimen 
5 mm at 0°C are as follows: Rp0.2 = 476 MPa, Rm = 620 MPa.
CONCLUSION It has been found that the microstructural aspect significantly affects ductile fracture initiation.
Stable crack growth cannot be exactly predicted without modification of the existing FE mesh, which is a limiting factor of this procedure for the time being.
Brocks, "Numerical Round Robin on Micro-mechanical Models - Results", ESIS TC8, GKSS Research Center, Geesthacht, (2000)

School of Mechanical Engineering, Harbin Institute of Technology Shenzhen Graduate School, 518000, China 2.
Introduction When developing new dental restorative materials, manufacturers must be able to predict the properties of new materials and their performance in the oral environment.
A number of uncertain factors are involved, each of which has the potential to introduce inaccuracies [2], for example, operator’s skill, prosthetic material, or cast shrinkage [22].
Accurate duplication of the movements of the teeth and condyles during function within a real oral environment are influenced by many soft tissue factors, such as the ligaments of the TMJ and masticatory muscles.
Pameijer, J., Periodontal and Occlusal Factors in Crown and Bridge Procedures, Chapter 7. 1985: Dental Center for Postgraduate Courses, Holland

（a）stress versus strain curve at 760℃ （b）stress versus strain curve at 790℃ （c）stress versus strain curve at 820℃ （d）stress versus strain curve at 850℃ （e）stress versus strain curve at 885℃ （f）stress versus strain curve at 910℃ （g）stress versus strain curve at 935℃ （h）stress versus strain curve at 960℃ Fig.2 Stress versus strain curves in 760~960℃ temperature interval at different strain rates It is found from Fig.2 that deformation temperature and strain rate are the most intensive factors to affect flow stress.
According to creep model, under low stress condition, relationship of flow stress and strain rate can be expressed as: (1) While under high stress condition, relationship of flow stress and strain rate can be expressed as: (2) Combining equality (1) and (2), relationship of deformation temperature, strain rate and deformation stress can be expressed by Jonas hyperbolic function as: (3) Where is strain rate; is structure factor; is stress level; is peak stress or steady state flow stress or flow stress corresponding some appointed strain capacity; is stress index; is deformation activation energy, which is an important parameter to attribute heat deformation; is gas constant; is thermodynamics temperature.
Temperature and strain rate are the most intensive factors to affect flow stress.
Stroshkov, et al., Structure and mechanical properties of VT22 (a+b) High strength titanium alloy semi-products, A.
[8] M.Brun, G.Shachanova, Principles of titanium alloys structure control with the purpose of increasing their mechnanical properties.