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Introduction Polymer hydrogels are hydrophilic crosslinked macromolecular systems capable of retaining significant amounts of water, while retaining the properties inherent in solids (a certain shape, mechanical moduli that characterize the properties of a material under tensile and shear strains).
The appearance of new application field of polymer hydrogels puts forward certain requirements for their properties, the most important of which is biocompatibility.
However, they are poorly biodegradable and lack antibacterial properties.
The high interest of researchers in biopolymers is also due to economic factors: low cost of their production, environmental friendliness and a variety of rich raw materials.
The physical and chemical properties of chitosan depend on its molecular weight and the degree of deacetylation.

One of the most significant factors on quality of stamped components as well as its manufacturing process robustness is the friction between tool and sheet material.
Figure 1: Mechanical properties of different steel grades [2] It is very expensive to repair worn or defect tools [7].
- How is the surface enlargement affecting the restraining forces while deep drawing?
While restraining forces of DC04 were affected by the lubricants viscosity after stretching, DP1000 does not show sensitivity to this effect.

Sandbag sand barrier have impact on vegetation, the soil hardness at different depths is indirectly affected by the vegetation to be affected.
Soil hardness has an important impact on physicochemical properties of soil, such as Permeability of soil aeration, Nutrient existence form and conversion, plant growth, microbial activities and so on [3].
Soil hardness is one of the important physicochemical properties of soil.
Desert shrubs affect deeper scale, also play a role in a relatively depth, two synergistic effects of two kind of plant roots make the overall trend not unchanged.
Visibly, sand barrier affect vegetation restoration, and have impact on soil hardness through the special role of vegetation roots.

As concerns delamination phenomena, notice that for the examined case of Apulian tuff masonry arches the bond between masonry support and FRCM reinforcements is a critical aspect, and debonding phenomena may significantly affect the overall strength of the construction.
The obtained values of the main mechanical parameters are: average flexural strength fmf=2.73 MPa, average compressive strength fmc=7.40 MPa, average Young Modulus Em=8100 MPa.
For the other two accelerometers similar values and trends of the dynamic amplification factor have been observed.
It results that down to 4 Hz the dynamic amplification factor gradually decreases from about 1.18 to about 0.72; after 4 Hz a sudden increase is observed, with a peak of about 3.62 at 6 Hz; finally, a decrease of the dynamic amplification factor occurs, until the value 2.74 recorded at 8 Hz.
Moreover, in case of materials having poor mechanical properties like the tuff, also the influence on the dynamic behavior of the elastic deformability of the blocks and of the rounding of the edges of the block due to the impacts and to the low tensile strength of the material should be considered.

Blow molding evolved from the traditional blowing glass to plastic materials, as it can be engineered to provide bottles with a variety of dimensional and mechanical properties.
The idea of reheating a thermoplastic material, and then stretching it in order to enhance its properties, was first employed in extruded sheet in 1930s.
Although differences in mechanical properties of the two materials leads to different cutter material, the authors undertake the usage of the same cutters, in terms of dimensions, as well as the same toolpath strategies and similar machining parameter values for comparison reasons.
All these factors are affected by the design and mold material.
Moreover, their mechanical properties must be defined: maximum load, handling stability, barrier and stress cracking.

Introduction Abrasive water jet is a new technology which rapid rise in the 1880s, compared with the traditional processing technology, as a kind of cold processing[1], It has many advantages as follows: first, it does not change material basic mechanical, physical and chemical properties in the machining process ;second,it hasn’t processing residual stress;thirdly, the parts that has special requirements such as local cannot have the change of heat, the workpiece surface can't have processing knife grain ,can process by high pressure abrasive water jet.
At present general methods of blade polishing are: six coordinate abrasive belt grinding, peening[3] and vibration strengthening, etc.but these methods have some defects as follows:in one hand, when we polish workpiece using sand machine,it is easy to cause the workpiece heat distortion[4] beacause of friction between sand grain and workpiece getting hot; in the other hand,Three dimensional vibration strengthening and polishing can only for some small blade; Thirdly, when using six coordinates abrasive belt cuts blade[5], blade root and convex platform cannot be polished, and should often change sand belt, which seriously affects the processing efficiency and increases the processing cost[6].
Figure 3 200 Mpa, 90 °, 1000 mm/min pure water jet erosion surface morphology The experimental research shows that the impact action makes the material fracture and flake to remove when abrasive water jet angle of incidence is vertical 90 °. with the same process parameters of pure water jet under,when abrasive flow is 180 g/min, abrasive water jet removal is 99.3 mg/s, the removal rate of abrasive water jet is much higher than pure water jet. but the material surface will appear erosion pit formed by a lot of abrasive the impact action, which seriously affected the material surface quality.
Figure 4 120 Mpa, 30 °, 2000 mm/min abrasive water jet Conclusion (1) Based on the experimental research, the pressure of water jet is the main parameters which affects the removal rate.
(2) The incident angle is the main parameters which affects material processing surface morphology.

It has been reported many times that quaternary AlCrSiN coatings promote a higher level of properties than typical TiAlN or CrAlN coatings [1,2,3].
Every type of coated cemented carbide turning insert was tested three times in order to exclude the impact of other factors involved in the process.
Cavaleiro, “High-temperature tribological properties of CrAlN, CrAlSiN and AlCrSiN coatings,” Surf.
Lee, “Effect of cathode arc current and bias voltage on the mechanical properties of CrAlSiN thin films,” Surf.
Mitterer, “Influence of Al and Si content on structure and mechanical properties of arc evaporated Al–Cr–Si–N thin films,” Thin Solid Films, vol. 534, pp. 403–409, May 2013

Hydrogen negatively affects the plasticity of titanium and its alloys.
In this case, the δ value of the UFG alloy decreases by a factor of 1.3, while for the FG alloy, δ is almost 2 times less.
Zhu, Fundamentals of Superior Properties in Bulk NanoSPD Materials, Mater.
Miyazaki, Mechanical properties of a medical β-type titanium alloy with specific microstructural evolution through high-pressure torsion, Mater.
Wu, Thermo hydrogen treatment for microstructure refinement and mechanical properties improvement of Ti-6Al-4V alloy, Mater.

Nevertheless, the failure is still a hard parameter to determine and it depends on a larger number of factors like pre-existing crack size, propagation mode, velocity of crack propagation, etc.
It is a good option to solve fracture mechanical problems.
The coefficient Kr is a function of the material properties and the element length Li.
Rocha [4] modeled the random properties of the material defining the toughness Gf as a random field with a Type III Weibull extreme value distribution, given by Eq. 7.
Furthermore, the length of the elements is different where the ECR depends on the length, as the ECR is dependent on the length, it is also introduced variability in the properties of the resulting model.

The physicochemical properties of the plastics are summarized below: Table 1.
Its unique properties make it widely used in industrial and commercial technologies.
As globally, rapid urban waste growth and inadequate plastic waste management in Azerbaijan are significant factors affecting the environment and climate.
Perspectives on plastic pyrolysis for fuel oil production: Key factors and challenges.
Polymeric materials and properties.