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Among these materials, hollow TiO2 nanotubes that have surface area-related properties can further improve photocatalytic properties because they demonstrate a superior electron transport. 2.
Definition of TiO2 nanotubes TiO2 nanotubes (TNTs) are tubular nanomaterials and exhibit unusual strength, unique optical properties and interesting semiconducting properties.
Among these factors, a high surface area can be one of the most important factors in certain photocatalytic reactions, as a large adsorption capacity of photocatalysts can promote the reaction rate [46-48].
Comparison of textural properties between various TNTs and Degussa P25.
In summary, knowledge of electrical properties is essential in the interpretation of photocatalytic properties of TiO2.

Amongst the various materials currently employed, the Ti–6Al–4V alloy has found extensive biomedical applications due to its good mechanical properties, excellent corrosion resistance and ability for osseointegration [1].
Each component introduces different cations and anions into the electrolyte solution which consequently influences the resultant coating characteristics and properties.
The electrolyte chemistry influences the nature of the pore (open or closed) and its size distribution in the coating, the phases present in the coating, and both these factors have a bearing on the corrosion performance of the PEO coating [3].
As the electrolyte composition and concentration strongly affect the properties of the PEO coatings [4], the present study is focused on establishing an optimized electrolyte system for the development of an oxide layer on Ti-6Al-4V implant material by PEO process, in order to improve its corrosion resistance under 4.5 pH osteoclast bioresorption and 7.4 pH simulated body fluid (SBF) physiological conditions.

Effect of Microstructure Ti-6Al-4V can be processed and heat-treated to produce a variety of microstructures having considerable differences in fatigue properties [73].
Dislocation slip mainly occurs in the primary α nodules along prismatic and basal planes with the largest Schmid factors [78].
Though different materials can certainly modify these fretting stresses because of the difference in material properties, friction, and wear behavior.
(1) Induce compressive residual stress in the surface layer via a mechanical treatment.
Mechanical Treatments - Compressive Residual Stress.

Solidification is one of the most critical processes in copper alloys, which will determine the formation of the bulk microstructure and then directly affect the mechanical and chemical properties of the alloys [75].
Precipitation particle size and its distribution have a decisive influence on the subsequent mechanical properties of high-strength and highly conductive precipitation hardened copper alloys.
In Fig. 13, the simulated cubic factors for the Cu-1.63wt.
Kister, Algebraic representation of thermodynamic properties and the classification of solutions, Ind.
Arai, Correlation entropy and its relation to properties of liquid iron, cobalt and nickel, J.

A large number of researchers have been trying Ti alloys in an attempt to combine most of their advantages, such as high specific yield strength, good corrosion resistance, excellent fatigue property, and biocompatibility [1-3].
In the early stage, the development of Ti alloys were mainly focused on the defense system technologies, thus their performance was a more crucial factor than the cost [4].
However, the cost problem cannot be overlooked any more, especially in the field of civil mechanical engineering.
Fig. 2 shows the results of EPMA mapping that not only the interstitial oxygen atoms but also the substitutional Al atoms dissolved from mold material affect the metal-mold reactions.

Introduction Several material properties strongly depend on the differences between ideal and real crystal structure.
The dislocation slip system (s.s.) considered is the primary s.s. of iron, <111>{110}, for which the average contrast factors for edge and screw dislocations were calculated using: c11=237; c12=141; c44=116 GPa.
In particular, the increased defect density seems to affect the solubility toward equilibrium conditions.
Once more, these results confirm the validity of adopting a lognormal distribution in mechanical grinding processes like high energy b.m..
Information on the primary slip system of cuprite (<100>{001}) was taken from the literature and further verified [20], in order to calculate an average contrast factor.

.% [7] and the highest properties are achieved near stoichiometry.
Long high-temperature heat treatments negatively affect the nanocrystalline structure of superconducting layers causing grain growth.
Specimens for TEM studies were prepared as thin foils of longitudinal sections of the wires by mechanical thinning and further chemical etching.
However, this composite demonstrates the lowest Ic (75 A), which testifies that the critical current is affected much more by the internal structure and morphology of superconducting layers than by their thickness.
Critical currents of the wires with ring Nb filaments annealed by various regimes versus average grain sizes of superconducting Nb3Sn phase Thus, the analysis of structure and morphology of superconducting Nb3Sn layers in composites with ring filaments, based on TEM and SEM data, has shown that the critical current of the superconductors is affected by a number of factors, such as the completeness of Nb filaments transformation into Nb3Sn (the residual Nb amount), morphology of superconducting layers (the presence or absence of columnar grains), average grain sizes of Nb3Sn and grain size scattering.

The chemical composition of the two materials and the mechanical characteristics are presented in Table 1.
Table 1 - Chemical composition and mechanical properties of materials [8] Chemical composition of materials C Mn Si P S Cr Mo Al 16Mo5 (W 1.5423) 0,12 – 0,20 0,50 – 0,80 0,15 – 0,30 Max. 0,0035 Max. 0,0035 - 0,45 – 0,65 0,010 – 0,030 X6CrAl13 (W 1.4002) Max. 0,080 Max. 1,0 Max. 1,0 Max. 0,040 Max. 0,015 12 – 14 - 0,10 – 0,30 Mechanical properties of materials Tensile strength [N/mm2] Drip limit, Rp0,2 [N/mm2] Elongation at tearing [%] Tearing energy at 20 oC [J] 16Mo5 (W 1.5423) 440 – 540 Min. 265 18 31 X6CrAl13 (W 1.4002) 400 – 600 Min. 210 Min. 17 Not specified For the estimation of the remaining life of the device under study, taking into account the particularities of the materials and constructional structure used in manufacturing, the provisions of the standards specific to the study materials were observed: SR EN 10028-2: 2009 Flat steel products for pressure vessels.
The following modules were used for research: - iRiS – Material: database with physical and mechanical properties of materials, including 16Mo5; - iRiS – Creep: for the creep evaluation of the long-term technical resistance; - iRiS – TRD: for the evaluation of creep depletion and the estimation of the remaining lifetime.
Conclusions The factors that influence the degree of creep strength of a metal equipment are diverse, and the phenomena that affect the good and safe operation are diverse.

By its properties, phosphogypsum is close to natural gypsum and can be considered as its potential substitute.
Phosphogypsum exhibits thixotropic properties, that is, it is capable of dissolving under mechanical influences (vibration, mixing, shaking).
Thus, in the initial stage, processes of dehydration and physicochemical sealing prevail, which leads to the formation of a denser sediment, which has cement bonding properties.
During interactions with water, phosphogypsum changes its state and properties, which affects the process of accumulation and migration of compounds, both in the dump itself and in the components of the natural environment.
The water-physical and agrochemical properties of phosphogypsum and soils were studied according to the generally accepted method.

Tensile tests on steel samples were performed to determine the mechanical properties of longitudinal/transverse steel reinforcement; the obtained mean values are listed in Table 1, where: fy and ft are the tensile strength at yielding and ultimate, respectively; ft/ fy is the hardening ratio, and et is the ultimate strain corresponding to ft.
Steel rebars’ properties.
STEEL TAPE Effective area of one cord “3x2” Acord = 0.538 mm2 Ultimate tensile strength* fsu > 2800 MPa Modulus of elasticity* Es > 190000 MPa Ultimate tensile strain esu > 1.50% *Properties related to the dry sheet (Data provided by supplier) Low density (LD) GEOSTEEL G600 Medium density (MD) GEOSTEEL G2000 High density (HD) GEOSTEEL G3300 N. cord/mm r = 0.157 N. cord/mm r = 0.472 N. cord/mm r = 0.709 Weigth, w = 0.67 kg/m2 Weigth, w = 2.00 kg/m2 Weigth, w = 3.30 kg/m2 Equiv. thickness teq = Atref· r=0.084 mm Equiv. thickness teq = Atref· r= 0.254 mm Equiv. thickness teq = Atref· r = 0.381 mm Fig. 2.
Typology and mechanical properties of the used strengthening materials [9].
However, it is worth noting that when using the epoxy resin to apply the steel tapes, the delamination clearly involved a rather significant portion of concrete substrate (Fig. 3c); when employing the inorganic matrix, instead, the collapse of the composite system only partially affected the concrete substrate and, conversely, it clearly involved the mortar layer, so that an interlaminar delamination in some portions of the beam took place (Fig. 3d).