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The rheological properties of special self-compacting concrete paste played a major role on its performance.
Therefore, under certain conditions, it can be simplified to the study of rheological properties of cement paste.
In this paper, by using R/S-SST rheometer produced by American Brookfield company continuous online detection of ultra low speed, with the yield stress changes over time to characterize the development and change of cement paste structure after mixing water, and the rheological properties model of cement paste through time was established, combined with the hydration heat curve test, discussed the control factors of rheological properties of loss with time.
Cement initial rheological properties is associate with cement hydration heat characteristics, structure formation and development, physical and mechanical properties.
Marsh, Properties and treatment of rotary mud, petroleum development and technology, Transactions of the AIME, (1931) 234–251

Experimental study on the impact of admixture for concrete heat of hydration and early-age contractile properties SUN Jian-cheng1,a, WANG Bo-jun2,b, ZHAO wen-zhong3,c 1College of Civil Engineering , Hebei University of Technology,Tianjin 300401, China 2College of Civil Engineering , Hebei University of Technology, Tianjin 300401, China 3 Highway Administration in Hebei Province,Shijiazhuang 050000,China aSunjancheng2000@126.com, b465391032@qq.com.
Key word: early-age Shrinkage, hydration heat, mineral admixtures, water reducer, contractile property Abstract : During the technology development of modem concrete, concrete structure crack (especially early-age crack) becomes more and more serious and has been one of main research directions of civil engineering.
The best program are obtained that double mix with 20% fly ash and 1.5% water reducing agent .Design mortar’s early anti-crack experiment, and study crack-resistance and other mechanical properties based on different ages & different mix proportion.
Experiment methods Mixing proportion optimization test for reducing the hydration heat In order to study the factors that affect the cement hydration heat, we have developed the following experimental scheme to analyze
Experiment methods Experiment mainly explore the composition of the fly ash, slag, water reducer, conservation of different raw materials affect on such as concrete early-age work performance, early-age crack resistance.

Titanium alloys have good mechanical properties and organizational stability.
However, due to the larger viscousity of titanium, a reasonable choice of the characteristic parameters of oilstone will directly affect the quality and efficiency of honing processing.
However, due to the larger viscousity of titanium, a reasonable choice of the characteristic parameters of oilstone will directly affect the quality and efficiency of honing processing.
Wang: China Mechanical Engineering Magazine Office Vol.14(2003) No.6, p. 1268-1271
Luo : The Neural Network Method of Mechanical Engineering (2003) No. 7, p.153 - 162

The article deals with the assessment of lubricants properties, monitoring of behaviour and consequences of the lubricant degradation process during its work in the machine lubrication system of aircraft engine by using tribotechnical diagnosis.
By used of ferrographic analysis was studied morphology of wear particles and physic-chemical properties of oil were determined with Fourier transform infrared spectrometry (FTIR).
The essence of a tribotechnical analysis is to evaluate presence of worn off particles in an oil system, to determine their concentration, number, geometric parameters and physical and chemical properties of the lubricant.
These factors cause troubles with functionally quality of oils and materials of mechanical components of lubrication system.
Bičejová, Factors influencing hydroerosion surface topography, In: Nonconventional Technologies Review.

Status and development trend about the fatigue properties of welded joints of magnesium alloy were reviewed.
Fatigue properties of welded joints of magnesium alloy can only reach about 60%~70% of base the metal [5].
The initiation, propagation and combining of micro fatigue crack might form one or more macro-cracks, which result in a decline in mechanical properties of magnesium alloy, and final fracture occurred by cyclic softening.
Secondly, Fatigue test is complicated because the fatigue of magnesium alloy is affected by environmental factor such as corrosive media, elevated temperature, and so on.
Trend of study on fatigue properties of welded joints of magnesium alloy There are a lot of factors influencing fatigue strength of welded structures, the main factors are including stress concentration, tensile residual stress, microstructure in the joint, weld defects and so on.

Then by using the tools of phase trajectory map, Poincare section and bifurcation diagram respectively, structure of the proposed model is identified, meanwhile, the properties of bifurcation and chaos are judged.
In other words, a nonlinear dynamics model must be employed to analyze the dynamic properties of the system.
In addition, the dynamics properties of the feed system are revealed as the stiffness is low or the support at both ends in varied.
And the dynamical behavior, processing quality and efficiency of the machine tools will be directly affected by this performance.
The feed system will become single degree of freedom system by means of identify factors of rotatable parts with moving parts of workbench.

Thus, the properties of concrete with plastic wastes are different, as they are affected by the previous treatment of those wastes, and the bonding strength between cement paste and plastic aggregates is also affected by treatment [5].
The properties of the concrete produced are also affected by the properties of that waste, which are the shape, surface roughness, and low fire resistance [5].
Adesina, Overview of the mechanical properties of concrete incorporating waste from the concrete industry as aggregate, (2018)
Nikbin,On the mechanical properties of concrete containing waste PET particles, Construction and Building Materials 47 (2013) 1302-1308
Prince, Physical and mechanical properties of mortars containing PET and PC waste aggregates, Waste management 30.11 (2010) 2312-2320

The degrees of three fillers affecting the wear of composites were CF>FG>SG, and that affecting the friction coefficient were SG>CF>FG.
Yang [3] et al. found that carbon fiber can reduce the friction and wear of PTFE based composites, while the mechanical properties of composites decreased with more graphite filler.
Each factor chooses four levels: 5, 10, 15 and 20 wt.%, and the interactions among the three factors are not considered.
The factors with larger R are more important than that with smaller R.
The degrees of three fillers affecting the wear of composites were CF>FG>SG.

All the results indicate that shape of shield materials affects the MSE properties much and the MSE properties of shield with square and circular shape with 3mm in depth are 39.3 and 53.5 dB, respectively.
In this paper, the Maxwell 2D software is introduced to study the magnetic shielding effectiveness (MSE) of iron plate, meanwhile, factors that influencing the MSE of iron plate is also investigated in order to provide another reference for magnetic shielding simulation.
Fig.1 Model of Maxwell 2D on magnetic shielding (left) and the uniform magnetic field where materials located (right) Results and discussion The simulated magnetic shielding effectiveness of shield with square and circular shape with 3mm depth is listed in Table 1. it shows that shape of shield materials affects the MSE properties much and the MSE properties of shield with square and circular shape with 3mm in depth are 39.3 and 53.5 dB, respectively.
That is, the increase of side length of magnetic shield will lead to the decrease of MSE properties of iron plate.
Lu:Journal of Mechanical strength.

There are multiple factors which have an effect on springback, such as mechanical properties of the material, friction conditions, and process parameters and so on.
Material Properties Simulation of the forming processes based on finite element method using Dynaform 5.8.1 software requires as input data the mechanical properties of the used materials.
Determination accuracy of the mechanical properties has an important influence on simulation results.
The results from the tensile test for FEPO steel are shown in figure 1 and the mechanical properties are presented in table 1.
By varying the values of all factors simultaneously, a statistically validated estimate of the results for every possible combination of the factors is possible.