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The utilisation of nano silica, nano alumina, titanium oxide and others are proven to enhance properties of concrete.
The advantage of nano materials in concrete is to pack the internal structure of cement paste and as result enhance the mechanical and durability properties of concrete.
Aqel Effect of Nano-clay on Mechanical Properties and Microstructures of Ordinary Portland Cement Mortar.
[6] Arikan, M., et al., Properties of blended cements with thermally activated kaolin.
[10] Rafat Siddique, J.K., Influence of metakaolin on the properties of mortar and concrete: A review.

Introduction Metal cutting is a severe plastic deformation process with high temperature, high pressure, high strain rate, and is also affected by thermal stress and phase transformation [1], and there will be residual stresses induced by machining in the surface layers.
Titanium and its alloys are widely used in aerospace field because of their light density, high strength, good resistance to corrosion and high temperature [2], but the residual stresses will seriously affect the dimensional accuracy and service performance of the workpieces [3].
The formation of the residual stresses’ final state will go through two steps: 1, the formation of the surface residual stresses induced by many factors during the process of machining; 2, the residual stresses will be redistributed to get a self-balanced state.
The size and shape of the workpiece will seriously affect the self-balanced result.
(a) The unmachined workpiece (b) the machined workpiece Fig.3 The workpiece before and after machining 3.2 Chemical Milling Here hydrofluoric acid was chosen as the corrosive as it can accelerated corrosion, and nitric acid was chosen as oxidant as it can inhibit the production of hydrogen to improve the property of the milled surface [11]. 704 silicone was used to protect the surfaces that don’t need to be corroded.

Introduction Since the microstructure of engineering materials determines a wide variety of mechanical properties, the study of microstructure-property relationship has been of great interest to the scientists and engineers.
Of all the microstructural parameters which influence the mechanical properties of polycrystalline metals and alloys, the grain size has been proved to be the most important.
The strong influence of grain size on the mechanical properties of materials, a subject of continuous investigation since the early work of Hall [1] and Petch [2], has been observed with historical roots going back many decades.
In recent years the availability of nanocrystalline (NC) materials paves the way for the potential discovery of new phenomena observable only in the NC regime, igniting a renewed interest in the influence of grain size on the mechanical properties of materials.
Local examination of the interaction between dislocations and grain boundaries A nanoindenter combined with an AFM (NI-AFM) has been used to study the effects of grain size on the mechanical properties of Ni at a local scale [21, 22].

They were conducted in a certain environment, constrained by economic, technological, political, and cultural factors outside the enterprise.
External Environment Factors Have Important Influence on Low-carbon Technology Innovation Activities of Petroleum Enterprises.
Internal factors determine success or failure of technological innovation of petroleum enterprises.
Through the above analysis, integrated low-carbon technology innovation process, external environment factors, internal factors , we can draw the low-carbon technology innovation system structure diagram, as shown in figure 1.
To optimize low-carbon technology innovation system for oil companies also mainly revolves some key internal factors, e.g., building research and development organizations, inputting innovation resource factors, and optimizing technical innovation security mechanism and operational mechanism, tec.

Arola and Ramulu [5] studied the impact of material properties on a superficial level honesty and surface that outcomes from grating waterjet (AWJ) machining of distributes.
Sekulic and Mandic [15] conducted experimental study to identify the affect of machining factors on surface integrity.
Manoj, et al., [20]studied the affect of machining factors in machining of Inconel 718 using AWJM.
The most important aspect affecting surface polish is the abrasive grain size.
This may be used to machine any delicate material without affecting the quality or qualities of the surface.

For the selected metal type, the main effect factors of mechanical and physical properties and its functional durability of the coating fiber is not only the integrity of metal film, but also the metal deposition thickness of the fiber surface, that is the surface metallization of the metal content of the fiber [2].
Thus, fiber volume ratio of surface area will be some changes (fiber weight loss), the results reliability are affected, and therefore this method not practical in the actual production value.
Put the fiber into the cylinder; be sure to catch the bubble out, so as not to affect the test results.

Mechanical anisotropy of aquifer also affects the well tide.
In this paper, a case study using data observed in the Chuan06 well was presented to analysis, so as to study the influence of the tidal drainage effect on well tide and explore the relation between the tidal hydraulic response and its influencing factors.
So, M2 and O1 tidal constituents was chosen to analyze to avoid the affect of barometric tide, and highlighting the response of water level to the earth tide.
Hsieh (1991), The estimation of fluid flow properties from the response of water levels in wells to the combined atmospheric and Earth tide forces, Water Resour.

The Characteristics of DR Materials and Production Process Generally speaking, Mechanical Properties of DR material depends on many factors including steel making, hot rolling and cold rolling process and so on, especially the annealing and rolling schedule is very important for cold rolling strip.
At same time, the strip surface defects such as water marks thus affect significantly the surface quality of strip products.
During the process of double cold reduction rolling, the roller surface temperature increase gradually to form a certain amount of roll crown due to the metal deformation[2], and it would produce a certain thermal profile, which would affect the strip flatness in a certain degree, so the roll must be cool down effectively.

CSc Department of Machining Technology, Faculty o Mechanical Engineering, UWB in Pilsen, Univerzitní 8, 306 14, Plzeň, ČR, jandecka@kto.zcu.cz Keywords: grinding, surface shape, CAD / CAM software Cimatron, technological module, postprocessor, the NC program Abstract.
The most dynamic development took place during the First Republic, which affected a number of affiliates in Europe and worldwide.
Solutions of the dependence of the undercutting of helical (screw) grooves based on the grinding wheel diameter, its thickness and depth of cut: Grinding shaped grooves on these instruments is affected by both the geometry and the properties of the helix, and the dimensional parameters of the instrument.
We are currently working to adjust the numerical model, respectively, its specification and the inclusion of other factors.

Temperature change affects not only the accuracy of measuring instruments, but also the size of the gear profile.
After defining the element types and material properties, we mesh the gear model, and add displacement constraints on it.
Therefore, the equation of gear profile can be modified based on standard involute equation, and we calculate the modifying factor by curve fitting.
Conclusion The thermal deformation of gear will affect the accuracy of gear measurement.
Chinese Journal of Mechanical Engineering, 2004(08), Vol.40 No.8:24–29