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On-line Measurement of Rheological Properties of LDPE, HDPE and LDPE/MICA Systems in Single-Screw Extrusion Hong He1, 2 a, Jianguo Zhou1, b 1College of Mechanical and Electrical Engineering, Beijing University of Chemical and Technology, Beijing, China 2Engineering Research Center of the Ministry of Education for Polymer Processing Equipment, Beijing, China aemail: hehong@mail.buct.edu.cn, bzhoujiangua@gmail.com Keywords: on-line measurement; rheological properties; single screw extrusion; thermoplastics.
The quality of extrudate is closely related to its rheological properties during extrusion.
Therefore, on-line measurement of rheological properties of polymer is important in extrusion process.
Introduction Rheological properties of polymer are essential during polymer processing.
Many factors such as temperature and screw configuration can affect the on-line viscosity.

But the problem is that the damage factor is subjective.
So how to determine the damage factor scientifically is a problem to be solved.
When the situation of the three former change less, the porosity and fracture are the main factors for resistivity of rock, different resistivity values mean different damage state.
The Relationship between Resistivity and Mechanical Parameters in the Uniaxial Compression Test In order to establish the relationship between mechanical property and electrical property in the process of rock damage, some marble specimens are selected to test in the uniaxial compression test.
Because resistivity is affected by moisture, temperature, the model established in this paper can only be used in the unchanged mechanical environment.

Microstructure and Mechanical Properties of Hot Rolled TRIP Steel Based on Dynamic Transformation of Undercooled Austenite Yunyang Yin a, Fang Fang b and Zhijin Fan c Research and Development Center of Wuhan Iron and Steel (Group) Corp, Wuhan 430080, China aemail:yinyyyang@sina.com , bemail:honeyfreda@163.com, cemail: fanzhijin@wisco.com.cn Keywords: Hot rolled TRIP-aided steel; dynamic transformation of undercooled austenite; Microstructure; Mechanical Properties.
As the unique properties of TRIP steels are obtained by the multiphase microstructure, the potential for optimizing the mechanical properties of TRIP-aided steel by the conventional rolled strategy is limited.
The volume fraction of retained austenite of the two steels is approximately identical, the different mechanical properties may be owned to the different fraction of bainite.
Table.1 Tensile properties and volume fraction of retained austenite of the investigated specimens isothermed time (min) Yield stress （MPa） Tensile strength（MPa） Uniform elongation (%) Total elongation (%) Yield ratio Vol.% of retained austenite 3 480 760 25 34 0.63 9.4 5 500 790 22 32 0.63 8.9 It is well known that the mechanical properties of TRIP-aided steel are dependent on several factors such as the size and morphology of the bainite packets, the volume fraction and distribution of retained austenite and martensite, the volume fraction and morphology of ferrite.
The grain size of ferrite does contribute to the strength, but there are other factors affecting the strength, as ferrite is only one component of the multiphase microstructure.

Scamans et al concluded that the distribution, composition, shape, density and corrosion potential of the precipitates were important factors affecting the corrosion behavior of alloys [18].
Frankel, Pitting of metals: A review of the critical factors, J.
Zhai, Influence of cerium on the microstructure, mechanical properties and corrosion resistance of magnesium alloy, Mate.
Weng, Effect of complex alloying of Sc, Zr and Ti on the microstructure and mechanical properties of Al-5Mg alloys, Mater.
Wang, Microstructures and mechanical properties of as-cast Mg-5Al-0.4Mn-xNd (x=0, 1, 2, 4) alloys, Mater.

The stress is laid on chemical factors having impact on carbonization and corrosion of main bars in reinforced concrete structural systems of balconies.
Introduction: Deterioration of main bars in reinforced structural systems of balconies is caused by both external factors characterizing the medium the construction is set in and interior factors representing the effects of concrete component properties, its treatment and cure.
Individual factors act paralelly and the result of their behavior is dependant on the character, extension and the sequence of behavior of each of them.
During chemical and physical processes concrete deteriorates in the course of simultaneous minimizing principal physical-mechanical properties of concrete which is called the corrosion of concrete.
The principal factors representing this group are sulphates.

The different levels of these factors are shown in Table 1.
The-higher-the-better performance for one factor may affect the performance because another factor may demand the-lower-the-better characteristics.
Sasaki, “Wear and mechanical properties of sintered copper–tin composites containing graphite or molybdenum disulfide,” Wear, vol. 255, no. 1–6, pp. 573–578, Aug. 2003
Kaczmar, “Production and wear properties of copper based MMC strengthened with δ-alumina fibres,” Arch.
ZHU, “Thermal expansion and mechanical properties of high reinforcement content SiC p / Cu composites fabricated by squeeze casting technology,” Trans.

Metallocene linear low-density polyethylene (m-LLDPE) has superior physical and mechanical properties.
Mechanical properties showed that tensile properties of all kinds of films blowing from ERE is better than the one from SSE.
This polyethylene has superior physical mechanical properties.
Measurement of Mechanical Properties.
Moreover, the mechanical properties of the end product made from ERE is higher than its counterpart.

The mechanical properties will change dramatically with the microstructure evolution under different cooling procedures [7].
The corresponding mechanical properties of diverse microstructures were investigated to reveal the effect of these influence factors.
The relationship of microstructure and mechanical properties.
Ghosh, Evolution of phases and mechanical properties of thermomechanically processed ultra high strength steels, Trans.
Wang, Effect of cooling procedure on microstructures and mechanical properties of hot rolled Nb-Ti bainitic high strength steel, Mater.

And thus the destruction is interaction results of material nonlinearity and geometric nonlinearity[1].As the non-linear changes of the mechanical properties of steel with the temperature increase, the compete path analysis of steel structure in fire is difficult, coupled with material nonlinearity and geometric nonlinearity.The simulation accuracy, which influenced by the mechanical properties and deformation path of the steel structure, directly affects the structural damage assessment and reinforcement scheme.According to research the dual nonlinearity problem of material and geometric, this paper established one finite element model of WILLIAMS structure under fire conditions, compared with the relevant experiment results, to verify the simulation method is accurate and effective.
The material properties of steel in high temperature The physical properties of steel in high temperature.
Compared to the usual, there is slightly different in physical properties of steel in high temperature.
High temperature has a significantly affect on steel properties,especially mechanics properties of steel.
:Modeling steel frame behavior under fire conditions, Engineering structures, vol.4(1991),p371-382 [4] Li,W.W., Analysis and research on the influence of essential factors in space grid structure on fire response.

The effects of Y2O3, La2O3 and Nd2O3 on the sintering, microstructure and mechanical properties of magnesia refractories were investigated.
However, they suffer from several drawbacks including low mechanical strength at high temperatures and poor spalling resistance, which negatively affects their performance and limits their applications.
Despite this, the behaviour of ReO in refractories systems, especially their effects on the sintering, microstructures and properties of magnesia based refractories have not been fully understood.
These results were attributed to two main factors.
Conclusions a) Additions of rare earth oxides improved sinterability and thermomechanical properties of magnesia refractories.