Search results

However, due to the brittle performance of ceramics, porcelain fracture and spalling fracture were often occurred and the use of all-ceramic restorations was greatly affected.
In 1886 Land CH reported the first case of all-ceramic crown restorations[1], which is valued for the good aesthetic characteristics, but the strength and toughness of ceramics is not enough and can not meet clinical practice needs. 1962, Weinstein et al [2] invented the porcelain with frit metal technology, which combines the strength of the metal basement structure and the aesthetics properties of the porcelain, to manufacture the metal-ceramic crown restorations which has certain aesthetic effect, this technology now is mature and has been widely used in the oral rehabilitation fabrication.
Meanwhile, the metal ions of the ceramic alloy not only make the porcelain prosthesis occurred fade, and some patients have metal allergies [3], the existence of these factors impels the development of the all-ceramic systems without metal basement structure.
However, the brittleness of the ceramic restoration is still the Achilles heel of restricting its application, greatly influence the reliability and stability of the material properties, also limit its features to play and practical application.
The main mechanical properties of all ceramic crown and crack germination, extension, penetrating and failure process was simulated in this paper and the results has important guiding significance for the clinical use of all-ceramic crown restoration.

Environmental pollution accelerates mutation and leads to the emergence of new biological forms possessing increased resistance, adaptability, and sometimes other properties dangerous for humans.
The composition and physical properties of the spent and contaminated oil may vary depending on the source.
An important unifying factor is that any oil sludge contains both water and solid impurities.
We need to find an approach that will allow the problem to be solved by not only conventional destructive methods, but also by techniques that enhance consumer properties.
Tyumen developers learned how to produce stable dry water that is not affected by negative factors.

The coiling temperature substantially affects the internal microstructure and magnetite phase.
Introduction Metallic oxide (scale) formed on the strip surface is a significant disturbance factor during hot rolling.
Correspondingly, the microstructure of the oxide scale is also affected by processing parameters, such as finishing and coiling temperatures, cooling rate, and cooling conditions under which the coils are stored.
Test coiling temperature was varied in the range of 540, 550, 560 and 570°C in a real hot rolling line to obtain different types of tertiary scales in terms of properties of the testing material [12].
They may affect the growth and distribution of magnetite and hematite layers, even the ions diffusion mechanism through the corresponding layers.

Strontium nitrate, barium nitrate and aluminum nitrate were all analytical reagents and added as additives to affect the crystal morphology of xonotlite.
During hydrothermal reaction the mass ratio of water and solid reactants (W/S) posed a great impact on the properties of products.
The concentrated pellets were apter to be broken by the action of mechanical agitation while the scattered pellets were easily reserved intactly.The increase of the yield of intact pellets would slightly decrease apparent density of the products.
Namely added ions would affect xonotlite fiber morphology and the fiber morphology could affect the apparent density and heat insulation capability of products.
Many factors could affect microstructure of xonotlite particles, such as raw material type and particle size, Si/Ca, W/S, temperature, reaction time, stirring speed and additives.

Benediktus Heat Transfer Laboratory, Department of Mechanical Engineering, University of Indonesia Kampus UI, Depok, 16424, Indonesia.
Thermoelectric refrigerator without heat pipes The experiment was conducted by varying several factors, including the input power, ambient temperature, and cooling load.
Figure 7 shows that the ambient temperature affects the obtained cabin temperature.
Figure 8 shows that the cooling load is one of the factors affecting the degree to which the thermoelectric system can reduce the cabin temperature.
The properties of water that being used in the calculation are density and heat capacity which value are 1.000 kg/m3 and 4.18 kJ/kg respectively.

The physical contradiction means a same parameter with two opposite properties, such as light and heavy.
Accordingly, the operator has to revise the size of the force for percussion immediately. 2.2 Measure 2: Problem of the value of the tapping frequency affecting the percussion effect and solutions thereof When a user subjects the patients to percussion via the intelligent percussion device, the stability of every tapping frequency must be noted, as the loosening of sputum from the deep part of a patient’s lungs can be affected by a tapping speed which is too fast or too slow.
This principle is not adapted to this measure; and (4) NO.28 (mechanical interaction substitution): Conduct the interaction between the object and an electric field, a magnetic field, as well as an electromagnetic field.
After turning on the intelligent percussion device, the nursing staff selects the data at the left bottom side of the display device, such as gender, age, weight, factor, division, language and wave.
Cucchiara: A Comparison of Manual to Mechanical Chest Percussion for Clearance of Alveolar Material in Patients With Pulmonary Alveolar Proteinosis (Phospholipidosis).

Smart surfaces and materials can play a significant role in intelligent, adaptive and responsive envelopes because of these intrinsic properties.
Today, reflection on operational strategies regarding the environmental question, energy efficiency and sustainability is one of the decisive factors for a change in the way of thinking in architecture.
Two main factors emerge that allow us to consider the so-called bio-inspired design approach in a new perspective.
Materials with self-healing properties.
At first, it was thought to add sugar to the mixture, which would have compromised the mechanical properties of the structure.

Experimental procedure and objects of research Specially designed test structures were used for the measurements of electrical properties of polysilicon layers (Fig.1).
Let us discuss how the magnetic field affects the conductivity of disordered systems.
Depending on the average grain size, the doping level and some other factors, different mechanisms of the charge carrier transport become dominant (from over-barrier mechanism to percolation of electrons via the states of grain boundary traps).
Efros: Electronic properties of doped semiconductors (Nauka, Moskow, 1979) (in Russian) [12] V.G.
Konopleva: Galvanomagnetic properties of disordered semiconductors (Preprint LIJF, Leningrad 1980) (in Russian) [16] N.C.

Introduction The temperature of induction motor windings is known to affect the operating modes of the electric drive, particularly static mechanical characteristics and it also violates the settings of optimal control systems on any indicator of quality.
In [1] the effect of temperature on static mechanical properties of the traction electric drive with induction motor ED-900 is investigated.
So the question of studying thermal properties of asynchronous traction motor as the first object of temperature control arises in this connection.
Mechanical model of the traction drive is also a part of power unit.
Thus, the mismatch of signals from shaft revolution detectors (the scaling factors should be taken into account) will make it possible to define the modes of stalled connection and its elimination by introducing a corrective signal to the control system.

The validity of the present method for the microscopic sliding and stick-slip instability is examined under various dynamic characteristics of the system, such as contact load, elastic stiffness, driving velocity and frictional properties.
Especially, wear is accelerated, and acoustic characteristic and machine life are also adversely affected by stick-slip vibration.
For the mechanical meanings and/or determination of parameters, refer to Hashiguchi and Ozaki [4].
Above-mentioned results demonstrate that the fundamental properties of the frictional sliding, including the rate- and state-dependency, could be described pertinently by the present finite element method.
The validity of the present method for the microscopic sliding and stick-slip instability is examined under various dynamic characteristics of the system, such as contact load, elastic stiffness, forced velocity and frictional properties.