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This study aimed to evaluate antimicrobial property of vanillin-incorporated orthodontic retainer PMMA resin on the biofilm formation of cariogenic bacteria.
The use of this appliance may affect the quantitative and qualitative distribution of oral microbiota [13, 14].
In addition, the presence of orthodontic retainers in the oral cavity limits the mechanical self-cleansing process providing by saliva and musculature movement.
With the resultant effect of all these factors, pH value of biofilm drops in the presence of fermentable carbohydrates and promotes the deposition and maturation of cariogenic biofilm that leads to enamel decalcification and dental caries.
Further studies are required to investigate the flexural strength, which is an important mechanical property, and other physical properties of this vanillin-incorporated PMMA resin along with the clinical evaluations to verify these results as well as the biocompatibility of this material.

According to Kim et al [1] most synthetic polymers can be modulated with respect to molecular weight, degradation rate, and mechanical properties.
The increasing of the PCL weight through the scaffold samples caused the improvement of mechanical properties.
Mechanical properties also influence specific cell functions within the engineered tissues.
Also, the increasing of the PCL weight caused the improvement of the scaffolds mechanical properties.
Calcite: Formation, Properties and Applications.

Introduction Because broken medias - coal and rock are non-uniform, a distribution of hard parcels in a seam is uncertain, so a broken coal and rock process of a continuous miner is random, and a cutting drum, as a broken machinery of a continuous miner, is subjected to random loads of changed size and unknown direction, which affects directly reliability of picks, mechanical parts, life of hydraulic components and electrical elements on the machine.
In order to improve applicability and reliability of a continuous miner, the paper attempts to research process of a continuous miner cutting different types of coal and rock, master natures of loads by establishing random load models of a cutting drum, explore effects of various factors on random loads.
(6) Where,,,- superposition factor of three direction loads; - pick amount at cutting region; - position angle of the i pick.
Simulation program design of random loads In simulated drum cutting process, the following questions should be considered: (1) Simulating cutting pure coal and rock layers by corresponding mechanical model; (2) Determining location and number of rock sandwich according to geological data, simulated cutting rock sandwich by rock mechanics model; (3) Hard parcels are randomly distributed in the seam, but for a coal seam, its size, shape and location is determined [6].
It can be found from results that loads of the drum are changing regardless of how is cut object, and there is significant volatility, which is reason of different pick number at each time, construction characteristics and physical properties of coal and rock.

Kimb Discipline of Mechanical Engineering, School of Engineering Faculty of Engineering and Built Environment, The University of Newcastle Callaghan, NSW 2308, Australia aMd.M.Islam@studentmail.newcastle.edu.au, bho-sung.kim@newcastle.edu.au Keywords: Syntactic foam, Manufacturing, Starch, Hollow microsphere, Analytical modelling, Numerical analysis.
The d0, when de = 0, in Eq. 2 was calculated for each microsphere size group using the packing factor (= microsphere bulk density / microsphere particle density) of bulk microspheres for a given mean radius of microspheres.
Once microspheres are wetted with binder, inter-particle distance would be affected by various factors such as starch content and IBVMS.
Ishai, "Mechanical Performance of composite sandwich beams with syntactic foam cores", R.
Preparation, structure and properties", Journal of Cellular Plastics, July/August, (1980) p223 [11] S.

Very often, only a thin layer of material, with high functional properties (e.g. high anti-corrosive properties at higher temperatures), applied on a relatively inexpensive base construction material is enough to fulfill the assumed customer expectations.
The processes described above leads to important structural changes in the subsurface areas of the bonded plates, strongly affecting the macroscopically measured ‘parameters’ characterizing the properties of the clad.
The rate of the heat transfer, the severe plastic deformation and the high pressure are the most important factors which induce the melting of the material close to the weld interface, and more generally, control the reactions occurring at the boundary between the solid and the liquid phase.
The rate of the heat transfer, the severe plastic deformation and the high pressure are the most important factors which control the reactions occurring at the Fig. 1.
The described processes lead to important structural changes not only inside the intermetallic inclusions but also in the subsurface areas of the bonded plates (e.g. inside the microstructure of the bonded plates near the interface); these changes strongly affect the macroscopically measured parameters characterizing the properties of the clad.

Unfortunately, these two properties are in conflict with one another.
Based on this understanding, studies are required to better understand the factors influencing the shrinkage and cracking of glossy ink jet coatings containing nano particle metallic oxides.
The optical properties of the whole coated paper dominate the print density achievable.
Salmen: Cell wall properties and their effects on the mechanical properties of fibers.
Moss: Effect of calendaring and wetting on paper properties.

Particle reinforced metal matrix composites (PMMC) possess many outstanding properties and are increasingly applied in automobile, aerospace, electronics and medical industries.
Introduction Particle reinforced metal matrix composites (PMMC) possess many outstanding properties such as high specific stiffness, high wear resistance, low density, high thermal conductivity, low thermal expansion, low fabrication cost, easy shaping etc.
Ge et al. [21] studied the surface finish, surface generation and the influence factors when high speed milling SiCp/2009Al composites using PCD tools.
Reinforcement volume fraction, cutting speed, reinforcement particle size, cooling condition, tool material grain size, heat treatment of the matrix and tool wear were these significant factors which influenced the machined surface quality.
Among the factors which affected Ra, reinforcement volume fraction was the most significant factor and followed by cutting speed and feed rate.

Composite materials show many excellent properties that traditional materials cannot achieve.
It determines that the structure and principle of the acoustic metamaterial will be not to seek the anti-electromagnetic response of the medium, but the abnormal mechanical vibration of the mechanical properties.
Thermal Metamaterial Due to the prosperous development of the metamaterials, their ideas soon spread from the initial light wave to the sound wave, mechanical wave and fluid, reflecting a variety of strange properties and applications.
The thermal concentrator can gather the heat flow in a specific region, and make the temperature gradient in the middle region rise without affecting the temperature distribution in the outer field.
Depending on its singular properties, thermal metamaterials will be widely used in the future.

Experiments have shown that PE pipes provide better operational safety and longer life, with excellent mechanical properties.
The RFW process produces high-quality welds with superior mechanical properties compared to the joined materials.
The welding joint achieved remarkable mechanical properties that were on par with those of the butt welding joint.
The TC tool has been employed in previous research [4] to compare the mechanical properties of welding HDPE sheets using a bobbin tool.
The considered welding process of polyethylene reduces its mechanical properties, and this is clearly demonstrated in this study.

The implication is that the grain boundary phase can be another controllable factor against contact damage and strength degradation even though it is not critical relative to the effect of grain morphology.
A mechanical contact is one of the important characterizations to consider the lifetime of these components [3].
While Si3N4 ceramics exhibit excellent thermal and mechanical properties at both room temperature and high temperature, the critical drawback is low reliability due to inferior fracture toughness rather than a commercial metal.
Many studies demonstrated that the mechanical properties of Si3N4 are influenced by a heterogeneous microstructure with weak grain boundary phases [9,10].
It is apparent that changing of grain boundary composition greatly affects contact damage and crack initiation load.