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To efficiently play the function of FA as the beneficial admixture of concrete, the activity of FA should be considered as a key factor in the mix proportion design of concrete.
Introduction To make fresh concrete with good workability and hardened concrete with required mechanical properties and ideal durability, it is important to make reasonably design for the mix proportion of concrete.
As made from crushed stone by machines according to certain procedures of crushing and sieving, machine-made sand has many characteristics different from natural sand such as irregular polygon particle with pointed edges, rough and new surface, which always brings about different properties of concrete from that of ordinary concrete with natural sand both in fresh and hardened states, especially the decreased flowing and serious bleeding of fresh concrete.
On summarizing the former test data of the mix proportion of concrete with machine-made sand and FA, this paper analyses the influences of these different ways on the properties of concrete based on the mechanism of concrete affected by FA.
The results reflect that the activity of fly ash relies on many factors both the active combinations in fly ash and the mix proportion of concrete especially the cement content.

With the increase of mining depth, increasing stress, coupled with complex geological structures, faults development, and water inflow increase, particularly high-stress become key factors induced pressure bump.
The number of coal mines affected by pressure bump will be increasing [3,4].
Impact orientation theory believed that impact orientation in coal seams is the inherent properties of coal and rock media and the internal factors of pressure bump.
In addition, the main reasons of pressure bump are mining depth, the geological structure and other natural factors.
Mining technology, support method and even the frequency and intensity of coal-gun become important motivating factors.

Study on the reasonable sand ratio in this state, research the effect of different rate of sand on the workability of concrete, and test the strength and deformation properties of concrete.
Sand ratio is an important parameter for concrete mix designing, because many factors that affect sand ratio, it is not possible to use one method to determine an accurate and reasonable sand ratio.
Different from the soil in the river sand, powder in manufactured sand can improve the performance of the fresh concrete and hardened concrete properties [4-8].
Concrete workability is poor, it is not easy to form the ideal aggregate interlocking structure, so that the compactness of concrete after hardening decreases, and affect the strength development of concrete and high sand ratio destroy the mechanical bite force among coarse aggregate [10].
Experimental research on the properties of sand impact on the concrete workability.

Factors of liquid basic physical properties and their hydrodynamic regularities. 2.
Factors of Basic Liquid Physical Properties and Their Hydrodynamic Regularities The identification of liquid basic physical properties is based on basic properties and equations of hydrodynamic processes which are aptly described in [1,2].
The basic physical properties and hydrodynamic regularities of the liquids used at hydrodynamic processes and which are significant for jet technology hydrodynamic processes are [6,7]: a) Physical properties: 1.
a) Physical properties 1.
Table 2 Graphic Model of Hydroerosion Factors Complex – Model KMF1 FACTORS INFLUENCING HYDROEROSION SURFACE TOPOGRAPHY Factors of basic liquid physical properties and their hydrodynamic regularities Technical factors influencing hydroerosive production process.

It is known that GFRP has excellent mechanical properties such as high tensile strength, corrosion-resistance and is lightweight.
Due to the outstanding mechanical properties of GFRP, it is recognized and used in engineering applications and various industries such as the maritime, aviation and automotive industries, and also for audio and sports equipment.
Material and Methods Epoxy Resin is classified into the group of thermosetting polymers that have excellent mechanical properties, thermal properties and high corrosion resistance.
Epoxy resin mixed with fiber reinforcement improves material properties with high tensile strength, high chemical resistance and excellent insulating properties [22].
As seen in Fig. 6, the feed rate is another factor that can affect tool wear.

Therefore, the objective of this research is to clarify the machinability of iron-based thermal spray coating and the factors resulting in severe tool wear.
The thermophysical properties of the thermal spray coating are shown in Table 1.
This result suggests that the vibration factor affects rapid tool wear during the machining of thermal spray coating.
Conclusions This study has elucidated the machinability of iron-based thermal spray coating for sleeveless engine cylinder, including discussion of factors such as conditions, tool wear, and cutting force.
(4) Thus, the mechanical wear caused by hard particles, thermal shock and also the vibration factor is the primary factor caused wears on the machining of thermal spray coating.

These elements contribute to improve the technological properties of the new filler alloy: melting, flowing, wetting and solidification.
It depends on the sizes of the sheets and the parameters of the flame: flow rates of acetylene and oxygen, power, temperature, type of flame (reducing, neutral, oxidizing), length, height over the brazing zone, tilt, as well as other factors.
The work temperature of the base metal is also an influence factor of the brazing time.
The properties of the new experimental and ecological filler alloy, regarding melting, flowing, wetting and solidification, have also been verified during the experiments.
The ecological properties of the new brass are adequate, as it exhales no lead, cadmium or other hazardous substances.

Introduction Silicon carbide particle reinforced aluminum matrix (SiCp/Al) composites are attractive materials in the various areas of the industrial application because of their superior properties.
By this way, the wear properties of SiCp/Al composites can be substantially varied through the changes in the microstructure, morphology and volume fraction of the reinforcing particulates.
Despite of these many advantages in the mechanical properties, however, they have serious drawback for industrial applications such as the poor machinability [2,3].
A lot of studies have been conducted for machining of SiCp/Al composites, and it is found that the morphology, distribution and volume fraction of the reinforcement phase are all factors that affect the cutting process [4-7].
During experiments, only one of the parameters, such as the table speed was varied while the cutting depth was held constant to observe the effects of individual parameter on machining properties.

Introduction Copper nanowires (NWs) have attracted great attention within the nanotechnology community because of its intrinsic low-cost and extraordinary physical/chemical properties.
For example, solar cells, flexible/stretchable electrodes, nanosensors, lithium-ion batteries, and nanocapacitors have been demonstrated with NWs of Cu or related composites.[1] Mechanical properties of Cu NWs, including plasticity and failure, are of critical relevance to the design and reliability of these devices.
A conceptual framework of "dislocation starvation" was proposed to be responsible for this apparent size-dependent behavior.[2] The nanometer dimensionality, however, is not the only factor that may affect deformation mechanisms and ultimate mechanical performances of NWs.
Until recently, as five-fold twinning was frequently observed in metallic NWs (e.g. platinum, gold, silver, and copper), extensive molecular dynamics (MD) simulations and initial experimental demonstrations have shown that such NWs may offer great potential of preserving ductility along with high strength.[6] However, so far there has been no clear experimental demonstration/confirmation to clarify the correlation between fivefold twinned (FT) microstructure and mechanical properties in Cu NWs.
This further verifies that microstructure control is a particularly effective mean for optimizing mechanical properties in NWs.

Discrete Element Analysis of Friction Coefficient on Granular Accumulation Qinliang Li1,a, Bin Zhao2,b, Bo Wang1, Bangchun Wen1 1 School of Mechanical Engineering and Automation, Northeastern University, Shenyang, China 2 School of Mechanical & Electrical Engineering, Henan University of Technology, Zhengzhou, China aliqinliang@vip.qq.com, bzhaobin978@163.com Keywords: friction coefficient, granular accumulation, angle of repose, DEM Abstract.
For instance, angle of repose affects the upgrading angle of conveyor in the mine production system, which results in large arrangement area, big project and long structure.
This paper aims to reveal basic characteristics and laws of mechanical properties using discrete element method, providing a basis for the selection of friction coefficient in future simulation work.
The granular surface roughness directly affects macroscopic accumulation characteristic of the heap.
Angle of repose varying with friction coefficient between particles µs,pp and µr,pp are both important factors which influence angle of repose.