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Effect of the mixing-melt and superheating on the primary Si phase of hypereutectic Al-20%Si alloy WANG Liandeng1, 2, ZHU Dingyi1, WEI Zheliang2, CHEN Yonglu1, HU ANG Liguang2, LI Qiuju2, WANG Yousheng1 1College of Materials Science and Engineering, Fuzhou University; 2College of Mechanical Engineering, Fuzhou University, Fuzhou 350108, China Liandeng@fzu.edu.cn; Liandeng@yahoo.cn Keywords: hypereutectic Al-Si alloy; pre-crystallized characteristic; melt-mixing; melt-superheating; refinement; modification.
Hence the modification of the Silicon to reduce the impairment of the aluminum is an effective and practical means to improve the properties of the Al-Si alloy [2].
Discussions The thermodynamic factor of different ingredient melts mixing with high- and low- temperature on the of primary Si of Al-20%Si The mechanism of refining solidified microstructure of the melt mixing process for present was mostly explained by the theory of the atom aggregation and structure of liquid metals [12-15], which did not consider fully the change of the thermodynamics caused by the melt blending process.
The temperature of mixed melt could be decreased remarkably by the melt blending process and the degree of undercooling of melt be increased before solidifying, thereby changing the pre-crystallized state of the melt and affecting the subsequent solidified structure.
/J·g-1 /J·g-1·K-1 / J·g-1·K-1 398 0.9 0.71 Table 1　Partial physical properties of Al-Si alloy Fig.6 Phase diagram of Al-Si binary alloy Besides, the quick melt-blending could cause the recombination of chemical bond in Al-Si alloy for the different composition between the high-temperature melt and low-temperature melt.

Introduction Earthquakes are one of the most destructive natural hazards that cause huge amount of loss of life and property.
Short column strength is governed by properties of the material strength and section.
Slender column strength is governed by many factors and requires special measures such as more reinforcement and bracing element to improve performance.
When working with reinforced concrete, a mechanical vibrator is to be considered as it is more suitable in providing efficient and high quality results.
The shrinking capacity during the curing period is not affected by the density of reinforcement.

Copper losses into slags have been the topic of long consideration [1-4] and there is consensus they depend on chemical dissolution of copper [5-7] and mechanical entrainment [8, 9], although there is disagreement as to the extent of each.
For similar feed rate, chemical composition, coexisting matte grade and process temperature differences of copper contents in slags can be explained by the smelting technologies, i.e. turbulence of the bath increases mechanical suspension of partly reacted concentrate and/or matte particles.
These conditions affect negatively the separation of matte and slag which takes place in the same vessel.
Since in highly oxidised high copper slags a large fraction of the iron is present as primary magnetite, a species showing strong magnetic properties, its separation from metallic and sulfidic copper, both nonmagnetics species, is possible via electromagnetic methods.
Association and dissemination of copper species in slags are key factors for copper recovery and it is relevant, to select the best operational conditions, they are determined beforehand.

Substitution of IIB elements with Mn and Fe in II-VI compounds will introduce magnetic properties and forms the so-called dilute magnetic semiconductors [1].
The heat exchange between the crucible and the furnace is mainly through radiation at the high temperature, but affected by the convection of the air in the gap.
The micro-scale interface morphology is another factor related to the heat transfer during the growth process, which has great influences on the crystal qualities of II-VI compounds.
Kenworthy: Journal of Electronic Materials Vol. 15 (1986), p. 361 [12] Zhou Yaohe, Hu Zhuangqi, and Jie Wanqi: Solidification Technologies (Mechanical Industry Publication, China 1997) (in Chinese) [13] Liu Juncheng, Jie Wanqi and Zhou Yaohe: Progress in Natural Science Vol. 7 (1997), p. 215 [14] Xiaohua Liu, Wanqi Jie, Yaohe Zhou: Journal of Crystal Growth Vol. 209 (2000), p. 751 [15] A.

Though the high density of ether group, PEO was suffered the disadvantages of high crystallinity and poor mechanical properties as well.
When the PEAm concentration is higher than 1.2 wt%, the increase of IP layer thickness may become the dominant factor for gas permeation, which lead to obvious decrease of CO2 permeance.
However for the membrane developed in this work, the CO2 permeance and CO2/N2 selectivity is also affected by the EO group content in membrane.

In the past, many researchers have attempted to modify the electronic properties of another photocatalyst TiO2 in order to extend its optical absorption edge into the visible light region and to improve the photocatalytic activity.
During high energy milling, SrTiO3 powders were subjected to severe mechanical deformation by the collisions with milling balls and pot.
Specific surface area of the sample is another important factor which affects the photocatalytic activity.

The size of the Si particles was characterized by average area, average perimeter and equivalent diameter, the shape of the Si particles was characterized by the aspect ratio and circuit factor.
This phenomena leads to an increase of an amount of crystal nucleus what affects on the size of grains and secondary dendrite arm spacing.
Allison: The effect of solidification time on the mechanical properties in a cast A356-T6 aluminum alloy, Society of Automotive Engineers, Inc., 1997

A prediction of the microstructure consisting of proeutectoid ferrite (α), pearlite (P), and bainite (B) has long been a desired technology, which would be the basis for balancing mechanical properties and good machinability of final products.
The α/P/B fraction after forging is mainly affected by both carbon and manganese content, austenite (γ) grain size (AGS), and cooling schedules.
Thus in our model, the critical enrichment factor C has been introduced in the new thermodynamic condition.

Simulation of temperature fields in the transport container Natália Jasminská1a*, Tomáš Brestovič1b, Marián Lázár1c, Mária Čarnogurská1d and Juraj Václav1e 1 Faculty of Mechanical Engineering, TU Košice, Department of Power Engineering, Vysokoškolská 4, 042 00 Košice, the Slovak Republic anatalia.jasminska@tuke.sk, btomas.brestovic@tuke.sk, cmarian.lazar@tuke.sk, dmaria.carnogurska@tuke.sk, eJuraj.Vaclav@ujd.gov.sk Keywords: transport container, temperature field, numerical simulation, ansys CFX.
C-30 transport container Due to the physical properties of spent nuclear fuel (SNF) the key factor for its removal from the reactor core is the storage pool in the immediate vicinity of the reactor.
For the calculation some structural elements were omitted, as their absence does not affect the velocity and rate heat dissipation (screws and connection points for measuring devices, provided the layer of radioactive shielding was added to the material thickness).

Figure 8 shows the dynamic viscoelastic properties (storage and loss modulus) of four of the same types of samples that were measured by SS curves.
The amount of cross-linking agent added to the elastomer also affects its characteristics, but if it is too small, the strength of the membrane deteriorates and is not recommended [28].
Kojima, 1992, Mechanical Properties of Shape Memory Polymer of Polyurethane Series, in JSME International J., Series 1, 35 (1992) 3
Ohyama, Examination of factors to improve the elongation and output of dielectric elastomers, In Proc.
Pei, Factors Influencing the Performance of Dielectric Elastomer Energy Harvesters.