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A number of nonlinear acoustic techniques based on harmonic generation [13-14], frequency mixing [15-17], acoustoelastic effect [18-19], dynamic resonance characteristics [20-21], crossmodulation technique, cascade modulation method, or cascade crossmodulation [22] have been developed to monitor damage and progressive damage in various materials such as concrete, metallic structures, composites [23-24].
(4) As the amplitude of the reference signal depends on a number of factors varying from sample to sample (e.g. the quality of acoustic contacts, the absorption of laser radiation by the sample surface), the normalization coefficient is introduced to the formula (4).
Vogel, “Neutron diffraction study of the contribution of grain contacts to nonlinear stress-strain behavior,” Geophys.
Schubnel, “Effects of pore collapse and grain crushing on ultrasonic velocities and V-p/V-s,” J.

Simulation model and method We use a coarse-grained model for the system consisting of two solid walls coated with polymer chains.
In two parallel (100) surfaces the spacing of bead is d=1.5874, and the adsorption density σg denotes the number of adsorbed chains per unit area.
The diblock copolymer chains are modelled using a widely utilized coarse-grained bead/spring model.
With the A-block length increase at fixed N=32, the total number of B-block is decreased.

Because of air pollution, the patients with lung cancer has increased 45.6% in China in the past 30 years, but the number of smokers has not significantly increased according to authoritative statistics.
The second particles of PM2.5 can be produced (gas →grain) by chemical multiphase reactions, such as tiny particles transformed by ordinary gaseous pollutants.
Coagulating Technology to Remove Ultra-fine Dusts The coagulation will agglutinate ultra-fine particles together to form larger grains so as to be captured by a dust-removal equipment.
(in 2004) carried out a research on the dust charged by corona between two plates and the coagulation in an alternating electric field (160 -500Hz) between two plates, and the results show that the number of particles less than 1μm decreased by 25- 29 % [5].

The range of chemical composition of Portland cement is shown in Table 1, which lists the minimum, average and maximum values for a large number of samples analysed [1].
Chemical analysis data [1] on major and minor constituents of Portland cements (wt%) Component Minimum Average Maximum Samples Average (100%) CaO 58.1 64.18 68.0 284 67.06 SiO2 18.4 21.02 24.5 284 21.96 Al2O3 3.1 5.04 7.6 284 5.27 Fe2O3 0.16 2.85 5.8 284 2.98 MgO 0.02 1.67 7.1 284 1.75 K2O 0.04 0.70 1.7 280 0.73 Na2O 0 0.24 0.8 263 0.25 SO3 0 2.58 5.35 280 - Free lime 0.03 1.24 3.68 132 - Total 99.52 100 The main composition studied was based on a maximum number of 7-components (i.e.
The C/S ratio of an interstitial glassy phase reported by [4] was reduced from 6.55 to 5.08, and microstructural investigations showed that C2S grains started to dissociate and leave a dendritic skeleton behind. 0 10 20 30 40 50 60 70 80800 1000 1200 1400 1600 1800 Temperature (οC) Mass (%) 7 Comp. 5 Comp 4 Comp b 0 10 20 30 40 50 60 70 80800 1000 1200 1400 1600 1800 Temperature (C) Mass (%) 7 Comp 5 Comp. 4 Comp a 0 10 20 30 40 50 60 70 80 1450 1350 1250 1150 1050 950 Temperature (°C) Mass (%) C3S Liq C2F KC23S12 C3AC2S is usually observed as the β-polymorph in Portland cement clinkers not as the γ-polymorph, typically containing 4-6% of other oxides [3].
K2O released deposits in the grain boundary or in the intra-crystal cracks within the αC2S, as documented by Chan et al. [5] who reported that the final K2O content could be a maximum of around 1.2% in α-C2S, which on further cooling converted to β-C2S stabilised by the presence of the K2O.

There exist a large number of hydrogen bonds within the CS molecules. 2920 cm-1 and 2873 cm-1 are two stretching vibration absorption peaks of C-H respectively.
Due to the formation of the coordinate bond, the electron cloud of the N electron in amino group has moved which results in the weakening of N-H and the power reduction in stretching vibration and flexural vibration, thus the N-H absorption peak moves to the low frequency direction along with the addition of inorganic grains. 1670 cm-1 emerged a new characteristic peak, and the deformation vibration absorption peak of the original amidogen at the position of 1601 cm-1 disappeared with red shift occurring, which indicates the two components have formed hydrogen bond complex.
From the figure 1, we can also find that the IR spectra of GP and CS/GP show little difference except a light one at high wave number section, which may be the result of the superposition of high-end hydroxyl group an alcoholic hydroxyl group after the composite of CS and GP.
As the gel is coated on the surface of Fe3O4 and the agglomeration of Fe3O4, it appears that grain diameter of Fe3O4 particles increase.

Due to the lapping pad 1 surface has a large amount of groove, its contact with the surface of the actual number of diamond abrasives is relatively small, lapping grain depth of cut into the work-piece surface is small, so in the initial stages of lapping, the work-piece material removal rate is relatively small.And with the lapping process, lapping fluid and broken chip can with groove to drain away in time, is beneficial to the work-piece surface of diamond grits, so the material removal rate increased.Lapping pad 2 with no grooves, chip block surface extremely easily, cause actual contact with the work-piece with larger area, single diamond abrasives share the grinding pressure is relatively small, go against the work-piece surface lapping grain, so the material removal rate decreases[14-16].
The influence of lapping parameters on the test results were analyzed by minimizing the number of experiments

A CCD camera determines on-line the number of pixels between the white and black transitions to the loading direction through a gap between the teeth of the die.
Then, the longitudinal strain was calculated on the basis of the number of pixels before and after deformation.
Namely, corresponds to the forest dislocations and dislocation cell walls formed by the prestrain and the internal stress developed by the heterogeneous deformation of microstructure: grains, hard phases such as martensite in dual phase steels, pile-ups of dislocations and dislocation cell walls.
Moreover, the pressure applied to the ferrite grains becomes higher in the 980 DP than in the IF steel.

The grinding process during surface preparation results the effect of cold working on the surface area, contain a large number of dislocations which assist diffusion [15].
The rapid outward diffusion of ion Mn will incorporate with Cr-rich oxide through grain and other short circuit area on the alloy system that enhance the protective barrier.
Acknoledgements The authors would like to acknowledge the support from the Ministry of Higher Education Malaysia form the Fundamental Research Grant Scheme (FRGS) under a grant number of FRGS/1/2020/TK0/UNIMAP/02/43.
Szpunar, Effects of grain sizes on the oxidation behavior of Ni-based alloy 230 and N, J.

Machining Science & Technology, 1997, 1(1):113-152. ].There are also demands to process a large number of holes for connection and assembly, but many problems such as delamination, burr, chipping, poor machining quality and tool wear in drilling of C/C composites exist due to inhomogeneous, anisotropic, wear resistance and varying thermal properties of the composites [[] Hojo M, Yatomi M, Tsuda H, et al.
Rotary ultrasonic machining (RUM), as a non-traditional machining method, has a large number of advantages in the aspect of hard brittle materials processing compared with conventional machining [[] Pei ZJ, Khanna N, Ferreira PM (1995) Rotary ultrasonic machining of structural ceramics-a review[C].
The trajectory of a single diamond grain can be described by the set of equations[17]: X=rcosωt Y=rsinωt Z=Asin2πft+vft (1) Where r is the radius of the tool, ω is the angular velocity of the spindle, A is the amplitude, vf is the feed rate, f is the vibration frequency and t is the time.
Figure 3 Experimental set-up Figure 4 Tool parameters Table 1 Tool parameters Parameter Value Parameter Value Outer diameter 12 mm Inner diameter 9.8 mm Grit size 80/100 Grain concentration 100 Bond type Brazing-bond Grits distribution 12 columns 3.2 Experimental conditions The C/C composites workpiece (Chaoma technology corp., Xi’an, China) was 2.5D acupunctured structure which consisted of 35% carbon fibers and 64% carbon matrix made up of resin carbon and pyrolytic carbon.

In order to keep hot bitumen on the surface of the mineral material grains during the storage and transportation of SMAM, the special stabilizing (structuring) additives that increase the thickness of the film binder are added to them.
We can assume that this is due to the presence on the crushed cardboard surface of the significant number of interwoven filaments, covered with bitumen membranes, which provide resistance to the binder stretching, and can compress like a spring.
CONCLUSION At the interaction of bitumen and fine-grained paper the light oily fractions of organic binder penetrate deep in the micropores.
Work performed as part of the competition in 2014 projects oriented basic research on interdisciplinary topics, conducted jointly by the Russian Foundation for Basic Research (RFBR) and the Government of the Belgorod region under contract number 14-41-08027 NC / 14, as well as the state task Ministry of Education and Science of the Russian Federation №1950.