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In this acid treatment reaction, the effects of acid/fiber ratio (ml/g) on physical properties of obtained cellulose nanofibers were investigated.
Cellulose nanofibers can be obtained by mechanical and chemical paths.
The overall efficiency of the acid hydrolysis treatment and physical properties of obtained cellulose nanofibers are affected by several factors such as acid type, acid concentration, hydrolysis temperature, hydrolysis time, and acid/fiber ratio.
The main objective is to produce cellulose nanofibers from cassava pulp via acid hydrolysis method as well as study on the effects of acid/fiber ratio on physical properties of obtained cellulose nanofibers.
All reactions were carried out at 60 oC under mechanical stirring.

A study on machinability performance of silicon carbide paticulate reinforced metal matrix composite R.Ganesh , R.Satyaprakash, M.Prakash and K.Chandrasekaran Department of Mechanical Engineering, R.M.K Engineering College, Kavaraipettai, Tamilnadu, India 601 206.
Introduction The important factor that prevents the manufacturers from using MMCs is the difficulty in machining these materials [1, 2].
However, MMCs have outstanding properties such as high specific strength, high specific modulus, low ductility, high wear resistance, high thermal conductivity and low thermal expansion, because of the existence of hard ceramic reinforcement in their structure, they are difficult to machine [3].
The testing conditions, material properties and sintering temperature influences the surface roughness of the hole in a significant manner.
Reilly, Factors affecting the machinability of an Al/SiC metal matrix composite.

Influence of Modifiers on the Structure and Properties of Composite Coatings system Ti-B-Fe N.K.
The paper studies how microalloying with amorphous boron (Bam) and zirconia (ZrO2) influences the structure and properties of boride coatings.
Two factors are found to strongly affect the structure and phase formation in composite coatings produced by electron beam surfacing, especially when using thermoreactive powders: (i) high reactive diffusion between the composite and substrate components, which causes the coating structure degradation, and (ii) slight deviations from phase concentrations and equilibrium crystallization, which give rise to such nonequilibrium phases in the coating structure under the electron beam as ferroboron, ferrotitanium and binary eutectics.
Introduction As it is known from metallurgical practice, the melt properties can significantly change after complex microalloying and modification.
Such treatment neutralizes the negative effect of some detrimental impurities and can entirely change the structure and properties of the as-cast material.

The way in which it rains is an important factor, affecting the infiltration process in the landfill final cover.
The lateral flow was constantly overestimated, whatever hydraulic properties entered, but have not noted any correlation between predicted and measured values of the percolation.
These findings suggest that the forecasts made by the HELP algorithm should utilize hydraulic properties valuesthat reflect as closely as the operating conditions of the soil layers.
Among the studied factors were included precipitation intensity, duration, the model and engineering properties of the landfill being performed about 100 different combinations of these parameters.
Conclusions The design of final coating of an urban landfill requires knowledge about both the slope geometry and hydraulic properties of the materials used in its construction, considering vertical hydraulic conductivity of each layer, and transmissivity along the slope.

These iron oxide scale not only directly affected the steel plate surface quality and yield, but accelerated the roll wear.
Therefore, clearing oxide scale in time before rolling and in the rolling process had become an important process affecting the surface quality of steel plates.
The final rolling temperature directly affected the internal physical structure and mechanical properties of steel plate.
Wei Sheng-nan[10] considered that the jet water flow was a major factor influencing convective heat transfer coefficient, and deduced the corresponding formula.
In summary, the above authors studied mainly the relationship between high pressure water convective heat transfer coefficient and the steel plate surface temperature ,water density or water flow, water pressure, and considered one or two factors to calculate the convection heat transfer coefficient.

Ciela K [10,11] for radiation processing of starch physicochemical properties, crystal structure were studied.
(4) Biomass biodegradable material content of each component, molding process parameters and the use of such factors as the mechanical properties also needs more research.
Temperatures and ethanol effects on the properties of extruded modified starch[J].
Effect of Gamma Irradiation on Molecular Structure and Physicochemical Properties of Corn Starch[J].
Effect of natural additives on the rheological properties of cellulose fiber disperse systems[J].

Through mechanical particle size separation of ash and its physicochemical characterization, it was possible to prove that the chemical and mineralogical composition of the raw material is favorable for use in alkaline synthesis Furthermore, the ash particle size large achieved the best results of properties optical and microstructural, favoring its application to obtain films to be applied to selective surface.
Thus, the search for materials with interesting mechanical properties, involving small amounts of energy in its constructive process, that generate less polluting and waste or materials that could be easily degraded in nature.
Besides these factors, the need to use renewable energy sources, especially solar energy, given the reduction in the availability of fossil resources [1,14], linked the existence of many limitations on solar thermal conversion process, mainly linked to the materials involved in this process [15,16].
The optical properties were obtained from tests in the UV/Visible Spectrophotometer, Shimadzu UV -2550 model with accessory for reflectance.
Therefore, only stainless steel and copper substrates Were evaluated concerning their optical properties.

In this paper, the situation about the blade machining with the finite element analysis is introduced, and the factors about the blade machining deformation is also summarized.
The most important is the mechanical and physical properties can be obtained from the finite element simulation results.
The deformations of the tool, work-piece and machine tools and other factors were considered in this model, but the coupling effect between the tool deformation and work-piece deformation were not considered.
Therefore, the factors of the milling force, deformation and radial cutting depth will affect each other.
Chinese Journal of Mechanical Engineering, 2001, 37(1): 6-10.

In the same year, the first paper on the influence of hydrostatic pressures on the mechanical properties of substances was published.
The mechanical force that fills in the missing pressure affects the nature of the stress state of the metal and changes the friction condition on die contact.
The data [5] were used to determine the mechanical properties of the composite components.
The material of the deformable billet has rigid-plastic properties specified by the material model (Eq. 1).
Variable factors Quality criteria Draw-forming λ Die angle, deg.

However, the micro-crack nucleation and the propagation of “dominant” crack are strongly effected by stress state, microstructure of material and environmental factors.
The characteristic mechanical properties obtained from standardized experiments of tensile specimens are given in Table1.
Table.1 Mechanical properties of low carbon steel Mechanical properties At 20 degrees Celsius At 400 degrees Celsius Yield strength (Mpa) Tensile strength (Mpa) Elongation (%) Elastic Modulus (Mpa) Poisson’s ratio 335.5 471.98 32 2.28×105 0.303 330.5 421.58 25.4 2.05×105 0.296 Fig.1 The metallographic micrograph of low carbon steel Fig. 2 Geometry of the notched specimen Testing techniques and optical observation.
With the reducing of notched radius or the increasing of nominal strain amplitude, crack growth rate increased relatively, which meant geometry and loading conditions were the factors of the crack propagation.
The geometry and load conditions affect the damage rate, which means the smaller the notched radius, the greater the slope of surface damage variable curves is, also the larger nominal strain amplitude, the greater the slope of surface damage variable curves is.