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In all polymeric materials, water is required as a mobile phase to facilitate the transport of protons, but the water uptake also affects the mechanical properties of the membrane, acting as a plasticizer, reducing the Tg value and membrane elastic modulus.
Films based on cellulose acetate are known due to their very good mechanical properties: high tensile and impact strength, resistance to alkali, oil and solvent action alongside bio-inertia, bio-compatibility, bio-degradability and non-toxic character.
The absence of structural selectivity as well as reactive functionality confers these materials versatility of constructiveness, being able to modify mechanical, chemical and ionic transport properties by compounding with other polymers and / or quaternary ammonium salts.
If theirs mechanical and thermal properties can be improved by structural/ structuring modification, the conductivity can be increased by in-situ doping [21-23].
Because the structure / composition ratio is one of the factors that determine the conductivity value, structural characterization has been performed through X-ray diffraction spectroscopy.

Materials and Methods The influence of calcium stearate on the technological properties of the cement-sand mixture, on the strength characteristics, capillary water absorption, and water absorption kinetics was investigated.
Results The technological properties of the concrete mixture were investigated: density, air entrainment, mobility. 3.1.
Conclusion The main goal of this work was to compare the effects of powdered CS and CS in the form of a suspension on the technological properties of the concrete mixture and the physical and mechanical properties of fine-grained concrete.
[6] Maryoto A., Gan B.S., Hermanto N.I.S., Setijadi R: Effect of Calcium Stearate in the Mechanical and Physical Properties of Concrete with PCC and Fly Ash as Binders.
Influence of freeze-thaw cycles on properties of Integral Water Repellent Concrete.

When these substances get into the soil, they migrate into groundwater, which causes them to enter the food chain, technogenically affecting all living things [1, 2, 3].
They are able to adapt to various environmental conditions and can survive in conditions of increased metal content due to their adaptive properties [4, 5, 6].
However, there are more significant factors that instantly create conditions for exceeding the concentration of heavy metals in the soil, which accordingly affects the biometric parameters of plants - these are military actions.
It is known that nickel, due to its structure and ability to accumulate and assimilate, is toxic for most types of plants, affecting the activity of amylase, protease and ribonuclease enzymes, thereby slowing down the germination of seeds and the growth of many crops [10, 11].
The choice of statistical analysis methods and software depends on a number of factors, including the type of data, the purpose of the study, and available resources.

However, because of carbon fiber composite materials its unique physical structure and chemical properties, some phenomena liking delamination, fuzzing, thermal degradation, spalling and fiber pull-out are happened in the cutting process [3,4].
Therefore, it is necessary to study cutting parameters which affect surface roughness of CFRP, summarizing the influence law of each factor and then determining the mechanical processing scheme.
Fig. 1 Experimental set-up for milling The regression analysis for four factors at three levels was used for the elaboration of the plan of experiments.
Table 1 indicates the factors studied and the assignment of the corresponding levels.
Table 1 Assignment of the levels to the factors Level factors Level -1 0 1 [m/min] 157.0796 201.0619 245.0442 [mm] 0.2 0.6 1 [mm] 1 3 5 [mm/min] 100 200 300 Results and Discussion The surface roughness (Ra) was evaluated with the surface roughness measuring instrument, according to ISO 4287/1.

The crystal plasticity (CP) model is widely used in many applications to link microstructure and mechanical properties.
It is well known that the mechanical properties of metal materials are determined by the microstructure.
Therefore, learning about the quantitative relationship between the microstructure and mechanical properties is very important [2].
While the focused mechanical properties can be various from microscopic level strain partition, macroscopic flow behavior, to fracture and fatigue properties, etc.
This model includes more microstructure information compared with the phenomenological one and it has more parameters affecting different properties of the material, such as grain size and dislocation density.

The contact conditions between ball, retainer and race affect the durability of the bearings.
Table 2 presents their mechanical properties.
Mechanical properties of the specimen (a) Bearing steel, SUJ2 Young’s Modulus (Gpa) Poisson’s ratio 207 0.29 (b) Silicon nitreide ball, TSN-03 Bulk density (g/cm3) Bending strength (Mpa) Fracture toughness KIC(MPam1/2) * Young’s modulus (Gpa) Poisson’s ratio 3.23 1011 6.6 294 0.27 * The value was measured by the IF method.
Acta Polytechnica, Mechanical Engineering Series, 1 (1947)
Acta Polytechnica, Mechanical Engineering Series, 2 (1952)

In the studied conditions it was observed that hydroxyapatite layer has influence on corrosion resistance properties.
Kroll in 1946, demonstrating their excellent biocompatibility, corrosion resistance and high mechanical strength, making them the most used biomaterials.
Moreover, different techniques are currently being used to obtain coatings of biotolerable materials with mechanical strength and with a bioactive layer [9-12].
However, the alterations introduced in this layer during the coating process can affect corrosion resistance, which is one of the main factors that renders titanium an excellent biomaterial [1,5,6].
Thus, physical properties of the coating, such as size, morphology, present phases, crystallinity, and thickness, must be evaluated.

For that reason the knowledge of the mechanical properties of these deformation layers are of vital importance.
For that reason the microstructure and furthermore the mechanical properties of such deformation layers are of interest.
In the last decades a variety of studies have shown that severe plastic deformation (SPD) is capable of producing materials with remarkable physical and mechanical properties due to a strong grain refinement [3,4].
It should exclusively affect the absolute value of torque.
Badeshia: Bainite in Steels, Transformations, Microstructure and Properties (IOM Communications LTD, England 2001) [8] F.

Impact of corona treated hemp fibres onto mechanical properties of polypropylene composites made thereof.
Plasma modification of sisal and high-density polyethylene composites: effect on mechanical properties.
Thermo mechanical properties of the silanized-kenaf/polystyrene composites. eXPRESS Polymer Letters 2009;3:657–64
The role of interfacial interactions on the mechanical properties of banana fibre reinforced phenol formaldehyde composites.
Improving softwood mechanical pulp properties with Ophiostoma piliferum.

Synthesized CHA mimic for composition, structure, nano dimension and morphology bone apatite crystals and their chemical-physical properties resemble closely those exhibited by enamel natural apatite.
The experimental results point out the possibility to use materials alternative to fluoride compounds which is commonly utilized to contrast the mechanical abrasions and acid attacks.
Poorly crystalline HA nanocrystals have excellent biological properties, lack of toxicity and inflammatory and immunologic responses.
In addition they show bioreabsorption properties under physiological conditions.
Dental erosion in Icelandic teenagers in relation to dietary and lifestyle factors.