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In the optimization of preconcentration parameters, the optimal adsorption, desorption, and enrichment factors were obtained at pH 4, the adsorbent mass of 90 mg, adsorption time of 95 min, Cu(II) concentrations of 7 mgL-1, and Na2EDTA 1 M.
However, chitosan is unstable in acidic media, with low thermal stability and mechanical strength.
Therefore, modifications are required to increase the adsorption capacity and mechanical properties [11,12].
Meanwhile, at a pH higher than the optimum pH, the value of adsorption, desorption, and enrichment factors decreased due to the competition between OH– ions with –NH and –OH groups in CS-DCMC to bind with Cu(II) ions.
The concentration of Na2EDTA significantly affects the percentage of desorption.

The calculation of the zeros of Eq. 12 can be carried out numerically for given values of material properties.
Fig. 4(a) shows the variation of the order of the singularity with the real time for the material properties given by Eq. 7.
The stress singularity factor is normalized by the quantity h λ−1 , giving it stress unit, as follows: );,( lim 0 1 0 tr h r K ij r ij θσ θ λ = − →       = (15) Fig. 4(b) shows the variation of the stress singularity factors.
It is shown that the stress singularity factors are relaxed with time, while the order of the singularity increase with time.
(a) Variation of the order of the singularity ; (b) Variation of the stress singularity factors.

So all the factors(such as matrix, particles, temperature and etc) that can affect the mico-plastic relaxations may have effects on the dimensional stability.
For this, some studies have been reported that the relationship between matrix, particles and properties of the composites[6-9], for example, the studies investigated that by the method of changing the component in the matrix alloy, such as adding Mg and Si to the aluminum matrix, it is beneficial to enhance the wettability and promote the spontaneous infiltration process and the mechanical properties[8-9].
All the factors that can affect the micro-plastic relaxations may have effects on the dimensional stability.
On the other hand, the formation of solid solution between alloy elements and Al has a certain effect on the lattice parameter, which will affect the macro size change of composite.

The properties of the produced nanoparticles indicate their high potential of in biophotonics.
In this paper we study structural properties of laser-ablated Si-NPs produced from silicon nanowires (Si-NWs) arrays targets fabricated by metal-assisted chemical etching (MACE) [10].
Analysis of Structural Properties.
Structural properties of Si-NWs were studied using a Carl Zeiss Supra 40 scanning electron microscope (SEM) and a ND-MDT SolverPRO scanning probe microscope.
We assume that several factors may affect this difference: (i) a lower thermal conductivity of Si-NW matrix as compared to bulk silicon, (ii) partial destruction of Si – Si bonds in the crystal lattice as a result of MACE, (iii) dependence on the buffer medium for ablation, (iv) difference between LD Si-NWs and HD Si-NWs.

The extent of electro-chemical corrosion depends on the electrical conductivity of the liquid, which affects the protective influence of the zinc layer over greater or smaller areas.
· Alkaline salts compound crystallizes in concrete expands. [2,3] Concrete Corrosion Under the Action of Ground Waters For the concrete buildings exposed to groundwater, the combined effects of corrosion factor occur. [4,5] Aggressive properties of water become more important when surface water has free access to a building or a permanent wash.
Reactions occurring between water and the concrete compounds are affected in addition to the chemical reaction and the conditions of movement of substances and products of reaction.
Aggression depends not only on chemical composition of water and cement but also other physical and biological factors. [12] For corrosion of concrete under the action of flowing ground water, dense concrete made with Portland cement with blast furnace slag or trass is essential.
Porosity is the main factor controlling the initiation of corrosion in concrete.

Structure and Properties of Ultrafine-Grained Cu-Cr Alloys after High Pressure Torsion D.V.
Introduction Severe plastic deformation (SPD) is well known now as a method to obtain ultrafine-grained materials with principally new physics-mechanical properties [1,2].
In a number of studies [3-8], the SPD method applied to widely used low-alloy chromium and zirconium bronzes was shown to improve their mechanical properties and thermal stability.
However, the size of the chromium phase in the cast material is large, about 10 microns, and this reduces the plasticity and strength properties of the alloy.
This leads to the heterogeneity of properties.

Hydrogen promoted degradation is one of the limiting factors to the structural integrity of the pipelines in long term service.
Therefore, it is essential to assess the hydrogen diffusion rate in the pipeline steels to predict their mechanical properties in service life.
The diffusion of hydrogen in steels is also affected by the microstructure of the steel.
The effect of different microstructures on the efficiency of hydrogen trapping in X65 pipeline steel was investigated by Park et al. [13] and reported that microstructures affecting both hydrogen trapping and hydrogen diffusion behavior and the trapping efficiency increases from pearlite to bainite followed by acicular ferrite.
The permeation current provides significant factors of hydrogen diffusion and trapping, viz.

Based on these results, the residual stress distribution on the affected machined layers can be controlled by optimizing the cutting sequence.
The chemical composition, mechanical properties and thermo-physical properties were presented in earlier investigations [4, 5].
As far as friction modelling is concerned, a simple model based on the constant shear hypothesis was implemented with the shear factor equal to 0.8.
Jawahir: International Journal of Mechanical Sciences Vol. 47 (2005), p. 1611-1628
Guo: International Journal of Mechanical Sciences Vol. 42 (2000), p. 10691086

In this investigation, it was found that the inhomogeneity of stress distribution in Cu interconnects is an important factor necessary for understanding textural transformation during annealing.
However, such relationships for the Cu interconnects haven't been firmly established and the driving force which can affect the textural transformation of Cu damascene interconnects during annealing were not clearly identified until now [6, 7].
This can be explained by the fact that the constraints generated by the sidewall increase at layers closer to the trench bottom and may affect the texture development of copper in the trench.
It was also assumed that the copper interconnect has isotropic mechanical properties.
From these results, it can be concluded that the stress distribution across the line depth and width is inhomogeneous in each Cu interconnects line, therefore, the stress state can be a important factor affecting textural evolution of Cu interconnects during annealing.

The ground grid of the substation are general network, which can be divided into long holes on the ground network and the square hole grid, such as the ground network of the same size, the hole in mesh network than the long hole in the steel to be used more, but the square hole in net pressure due to both properties, impact properties are superior to long-hole ground network.
However, in the absence of galvanized steel corrosion resistance when the discharge current can still be affected, but to network with discharge currents (including stray current) electrolytic corrosion, the corrosion resistance increased very little compared with ordinary carbon steel, not significant improvement in network anti-corrosion properties.
When the copper and other metals (steel, water pipes, pipe, cable sheathing, etc.) co-exist underground, the copper as the cathode is not affected by corrosion, corrosion of the latter.
Is a layer of steel corrosion, galvanized layer have some degree of corrosion resistance, but in the discharge current and welding two kinds of factors, the corrosion performance of galvanized steel is not ideal, a lot of excavation findings also confirmed that .
Mechanical connection Chemical exothermic welding Figure 1 Exothermic welding and mechanical coupling of chemical comparison Application in engineering examples 110Kv jinshan substation is outdoor substation setting switchgears building and 110Kv outdoor switchgears, set type I road within station.