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The catalytic performance was found to be strongly affected by thermal treatment of the prepared catalyst prior to the reaction.
The preparation of gold-based catalysts has been widely studied [2-6] and the most significant catalytic properties of gold supported catalysts have been achieved for CO oxidation reaction at ambient temperature [4-7].
The dimensions of gold particles, support material, synthesis method, parameters for the preparation and the catalyst activation procedures are major factors to augment the catalytic activity [7-11].
As-synthesized resulting Au/TiO2 catalysts were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman Spectroscopy for measuring various properties (phase, structure etc).
In either case, the Au is clearly highly dispersed though the titania matrix, which should maximize its effect on the surface properties of the support material.

Their results showed that the choice of tool coating was the main factor influencing tool life and the primary tool wear mechanism was adhesive wear, which affected the CrN coating to a greater extent [2].
The experimental results showed that significant flank wear was the predominant failure mode affecting the tool life and the tool flank wear propagation in the up milling operations was more rapid than that in the down milling operations [3].
It was strengthened by depositing and deformed at high temperature, which has high strength, high fatigue property, and fine plasticity.
The chemical composition of the Ni/Al superalloy used in this work was listed in Table 1 and the main properties were described in Table 2.
Table 1 Chemical composition of Ni/Al superalloy C Cr Al Ti Hf W Ni 0.06-0.20 7.40-8.20 7.60-8.50 0.60-1.20 0.300-0.900 1.50-2.50 Balanced Table 2 Physical properties of Ni/Al superalloy Heat conductivity coefficient [W/(m·K)] Linear expansion coefficient [10-6/K] Hardness [HRC] Specific heat capacity [J/(kg·K)] 9.64 12.39 29 469 Two types of cemented carbide milling tools were utilized in this paper, the specification of which is shown in Table 1.

Therefore, elastic modulus is not the only factor that affects retention rates, other factors also play a role.
The loss of marginal adaptation is one of the most important factors that show the failure of a restoration and the reason for replacement [27].
This result was related to the good physical and mechanical properties of materials used.
Sun, Calcium and Phosphate Ion Releasing Composite: Effect of pH on Release and Mechanical Properties, Dent Mater. 25 (2009) 535-42
Wang, Mechanical properties and microstructures of glass ionomer cements, Dent Mater. 16 (2000) 129-38

The main benefits arising from the use of PMLSM include high thrust density, low thermal losses and, most importantly, the high precision and accuracy achievable from the simplicity in mechanical structure [1].
However, due to the lack of a transmission unit, the tracking behavior of a linear motor feed drive is prone to be affected by external disturbances and model parameter variations [2].
In the past decade, the variable structure control strategy using the sliding mode has been the focus of many studies and research for the control of the ac servo drive system because the sliding model control can offer many good properties, such as insensitivity to parameter variations, external disturbance rejection, and fast dynamic response [3].
After some mathematical manipulations, the control law is found to be (18) where q is determined by all disturbance, and . m and k are the total mass and the whole amplification factor from the control signal to the generated force, respectively.
Disturbance Observer The merit of the disturbance observer (DOB) is that it can estimate a disturbance and reject it without affecting performance.

Study on the Accurate Measurement of Film Thickness Zhiqiang Xua and Kaiguo Qianb Department of Physics, Kunming University, Kunming, China 650214 a x13808736648@yahoo.cn, bqiankaiguo@qq.com Keywords: ultra-thin films; material; accurate measurement; technology; methods Abstract.The thin-film technology is the hotspot of today’s material science research.The thickness is an important physical parameter of the film thickness, so measurement naturally becomes the important work of research into material properties.
In the sub-micron level, the thickness of film has great relevance to mechanical, electrical, magnetic, optical and other properties.
The film material having special properties is different from the material, and thus has a wide application in the IC process.
If a group of single-layer thin film thickness is uneven, it will not only affect the thin film throughout the tensile srtenth, barrier properties, etc. but also subsequent processing of the film.
However, the use os x-ray diffraction methods to determine the monolayer thickness, there are some nagative factors:Firstly, this method has a selectivity of materials, this method cannot be used in some material; Secondly , since the monolayer film has only two interfaces, so its signal intensity of the x-ray diffraction is weaker than that of the multilayer film , and it’s not conductive to data processing; besides, there is no similar repetition period of the multilayer film structure, the diffraction peak is wider,.

A composition of agglomerated ZnO-Cu powder and respective produced coatings were evaluated for fouling properties via antimicrobial activity test.
Affected shipping vessels will have an increase of weight, subsequent potential speed reduction and loss of manoeuvrability thus will require a frequent dry dock cycle which is costly and time consuming.
Our earlier publications have demonstrated the successful deposition of an antibacterial/ antifouling properties of ZnO-Al coatings using cold spraying.
The binder powder had an irregular morphology and the mechanical alloying process uses a high energy ball miller (Simoloyer, ZoZ GmbH, Germany).
The colony forming units (CFU) was calculated by multiplying the number of colonies by dilution factor.

Table 2 outlines the mechanical properties of the materials used for the plate.
Additional solver properties, including initial conditions, analysis settings, fixed support, and outputs, were specified.
[2] A Guide to the Grades, Properties and Uses of Military Steel (2018) https://www.azom.com/ article.aspx?
Romijarso, Effects of austenitizing and forging on mechanical properties of MIL A-12560/AISI 4340 steel, IOP Conference Series: Materials Science and Engineering 202 (2017) 1-5
Bergmann, Ballistic ceramics and analysis of their mechanical properties for armour applications: a review, Ceramics International 47(7) (2021) 8743–8761

The shearing force is the basis to calculate mechanical parameters of the disc cutter and slitting machine, therefore, it is very important to obtain the accurate shearing force.
All of them reference the analysis method of the cutting machine with beveled shear blade and choose some coefficient to modify the results [2], this affects the calculation accuracy of shearing force.
Fig. 1 Principle of the disc slitting process Fig. 2 Acting forces of the disc cutter Fig. 3 3D modeling of the disc slitting Table 1 The FEM parameters Parameters value[mm] Thinkness of sheet 1.6 Thinkness of cutter 8 Radius of cutter 135 Blade radius of cutter 0.03 Clearance 0.06 Overlap 0.32 Table 2 Mechanical properties of galvanized sheet Yield limit σs[MPa] Ultimate strength σb [MPa] Elasticity modulus E0[GPa] Elongation δ5[%] Hardening exponent n 280 488 206 47.37 0.196 Finite element simulation of the disc slitting process Finite element modeling.
The mechanical parameters of galvanized sheet (see Table 2) were obtained by the tensile test.
Zeng, Criteria of metal ductile fracture and numerical simulation for metal forming, Chinese Journal of Mechanical Engineering, 38(2002)21-25

Danoyan and Piliposian [5] investigated the propagation properties of Love waves in a piezoelectric substrate carrying a hard dielectric layer.
Our objective is to reveal how dispersion characteristics are affected by material anisotropy.
For the above problem, the mechanical displacement w and the stresses (szx, szy) in the layer satisfy the following equations: (1) (2) where c44, c45 and c55 are the elastic constants; ρ is the mass density; an index after the comma denotes partial differentiation with respect to corresponding coordinates x and y; a superimposed dot denotes differentiation with respect to the time t.
(9) Solving the above equation, one obtains , (10) where is a dimensionless factor that reflects the layer anisotropiy and ; , where is the velocity of shear bulk wave in piezoelectric materials.
Their properties are: , and as well as , , and .

Introduction The control of the morphology and size of Si phase in Al-Si casting alloy has become the most important factor for deciding the characteristics of the alloy.
In this research, an electromagnetic vibration was applied to a solidifying Al-Si-Mg alloy and then the morphology and size of eutectic Si phase were observed and mechanical properties were measured.
A tensile test was carried out to evaluate the mechanical properties of the specimen at room temperature by using the specimen of ASTM E8M standard size.
As the results of tensile test in Fig. 4, the UTS and elongation was enhanced to around 47% from 126.5MPa to 186.9MPa and to 8.5 times from 1% to 8.5%, respectively, as increasing the frequency. 7.743 6.385 2.949 1.763 0.973 0.853 0.837 7.743 5.712 2.469 0.985 0.894 0.822 0.798 0 1 2 3 4 5 6 7 8 9 As-cast 60 200 300 500 700 1000 Frequency(Hz) Diameter( � �� � ) 4.2E5A/ � 1.05E6A/ � Fig. 3 Mean size of the eutectic Si phase with a different frequency and current density 126.51 134.89 136.92 171.85 173.08 180.93 186.93 1.00 2.00 2.56 4.81 5.50 8.05 8.50 0 20 40 60 80 100 120 140 160 180 200 Ascast 60 200 300 500 700 1000 Frequency(Hz) UTS(MPa) 0 1 2 3 4 5 6 7 8 9 10 Elongation(%) UTS Elongation Fig. 4 Variation of the mechanical properties as a function of the frequency It has been well known that the transformation of unmodified flake to modified fibrous structure arises from a very different type
The mechanical properties of electromagnetically vibrated alloy were increased as increasing the frequency due to the fine size and modification of eutectic Si phase.