Ultracondensed Matter by Dynamic Compression

McCune-Albright Syndrome (MAS) is characterized by endocrinopathies, café-au-lait spots, and fibrous dysplasia. Bisphosphonates are the most prescribed treatment for reducing the pain but their long-term use has been associated with atypical fractures of cortical bones like femur in patients. We present a 23-year-old girl diagnosed with MAS. She had an atypical mid-shaft left femoral fracture that happened during simple walking. She also had a history of long-term use of alendronate. Because of the narrow medullary canal, we used 14 holes hybrid locking plate for the lateral aspect of the thigh to fix the fracture and 5 holes dynamic compression plate (instead of the intramedullary nail) in the anterior surface to double fix it, reducing the probability of device failure. With double plate fixation and discontinuation of alendronate, the complete union was achieved five months after surgery

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A comparative study of functional outcome of dynamic compression plating versus interlocking nailing for fracture shaft to humerus at tertiary health care center

MedPulse International Journal of Orthopedics ◽

10.26611/10201132 ◽

2019 ◽

Vol 11 (3) ◽

pp. 70-72

Author(s):

Kale M S ◽

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Lamture D R ◽

Keyword(s):

Health Care ◽

Comparative Study ◽

Functional Outcome ◽

Dynamic Compression ◽

Care Center ◽

Health Care Center ◽

Interlocking Nailing ◽

Compression Plating ◽

Dynamic Compression Plating

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STRAIN CHARACTERISTICS OF SOIL AND METHODS OF THEIR DETERMINATION

Irrigatsiya va Melioratsiya ◽

10.35938/2018.1.12.10 ◽

2018 ◽

pp. 39-43

Author(s):

K.S. Sultanov ◽

P.V. Loginov ◽

Z.R. Salikhova

Keyword(s):

Dynamic Loading ◽

Dynamic Compression ◽

Loess Soil ◽

Seismic Loads ◽

Static Compression ◽

Plastic Model ◽

Laboratory Conditions ◽

Coefficient Of Viscosity ◽

Wave Problems

The method to define strain characteristics of soil under dynamic loading is proposed based on the results of experiments on dynamic compression of soils on the device for dynamic loading in laboratory conditions; the method allows solving wave problems with the statement similar to the statement of experiments. Using the proposed method, the modulus of dynamic and static compression, the modulus of unloading, the coefficient of viscosity of loess soil in the range of seismic loads are determined in accordance with elastic-visco-plastic model of soil developed by G.M.Lyakhov.

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Mechanical properties and microstructure of the Al0.3CoCrFeNiTi0.3 high entropy alloy under dynamic compression

Materials Science and Engineering A ◽

10.1016/j.msea.2021.141147 ◽

2021 ◽

Vol 812 ◽

pp. 141147

Author(s):

Xianzhe Zhong ◽

Qingming Zhang ◽

Jing Xie ◽

Mingze Wu ◽

Fuqing Jiang ◽

...

Keyword(s):

Mechanical Properties ◽

Dynamic Compression ◽

High Entropy Alloy ◽

High Entropy

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Pressure Equilibrium Time of a Cyclic-Olefin Copolymer

Polymers ◽

10.3390/polym13142309 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2309

Author(s):

Benedikt Roth ◽

Dietmar Drummer

Keyword(s):

Dynamic Compression ◽

Flow Behavior ◽

Superposition Principle ◽

Applied Pressure ◽

Thermal Shrinkage ◽

Compression Rate ◽

Rate Dependency ◽

Equilibrium Time ◽

Simulation Techniques ◽

Pressure Equilibrium

Integrative simulation techniques for predicting component properties, based on the conditions during processing, are becoming increasingly important. The calculation of orientations in injection molding, which, in addition to mechanical and optical properties, also affect the thermal shrinkage behavior, are modeled on the basis of measurements that cannot take into account the pressure driven flow processes, which cause the orientations during the holding pressure phase. Previous investigations with a high-pressure capillary rheometer (HPC) and closed counter pressure chamber (CPC) showed the significant effect of a dynamically applied pressure on the flow behavior, depending on the temperature and the underlying compression rate. At a constant compression rate, an effective pressure difference between the measuring chamber and the CPC was observed, which resulted in a stop of flow through the capillary referred to as dynamic compression induced solidification. In order to extend the material understanding to the moment after dynamic solidification, an equilibrium time, which is needed until the pressure signals equalize, was evaluated and investigated in terms of a pressure, temperature and a possible compression rate dependency in this study. The findings show an exponential increase of the determined equilibrium time as a function of the holding pressure level and a decrease of the equilibrium time with increasing temperature. In case of supercritical compression in the area of a dynamic solidification, a compression rate dependency of the determined equilibrium times is also found. The measurement results show a temperature-invariant behavior, which allows the derivation of a master curve, according to the superposition principle, to calculate the pressure equilibrium time as a function of the holding pressure and the temperature.

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Influence of artificial aging: mechanical and physicochemical properties of dental composites under static and dynamic compression

Clinical Oral Investigations ◽

10.1007/s00784-021-04122-0 ◽

2021 ◽

Author(s):

D. C. Gornig ◽

R. Maletz ◽

P. Ottl ◽

M. Warkentin

Keyword(s):

Mechanical Properties ◽

Water Sorption ◽

Artificial Aging ◽

Filler Content ◽

Dynamic Compression ◽

The Other ◽

Chemical Degradation ◽

Dental Composites ◽

Compression Tests ◽

Acid Ph

Abstract Objective The aim of the study was to evaluate the influence of filler content, degradation media and time on the mechanical properties of different dental composites after in vitro aging. Materials and Methods Specimens (1 mm3) of three commercially available composites (GrandioSO®, Arabesk Top®, Arabesk Flow®) with respect to their filler content were stored in artificial aging media: artificial saliva, ethanol (60%), lactic acid (pH 5) and citric acid (pH 5). Parameters (Vickers microhardness, compressive strength, elastic modulus, water sorption and solubility) were determined in their initial state (control group, n = 3 for microhardness, n = 5 for the other parameters) and after 14, 30, 90 and 180 days (n = 3 for microhardness, n = 5 for the other parameters for each composite group, time point and media). Specimens were also characterized with dynamic-mechanical-thermal analysis (compression tests, F = ± 7 N; f = 0.5 Hz, 1 Hz and 3.3 Hz; t = 0–170 °C). Results Incorporation of fillers with more than 80 w% leads to significantly better mechanical properties under static and dynamic compression tests and a better water sorption behavior, even after chemical degradation. The influence of degradation media and time is of subordinate importance for chemical degradation. Conclusion Although the investigated composites have a similar matrix, they showed different degradation behavior. Since dentine and enamel occur only in small layer thickness, a test specimen geometry with very small dimensions is recommended for direct comparison. Moreover, the use of compression tests to determine the mechanical parameters for the development of structure-compatible and functionally adapted composites makes sense as an additional standard. Clinical relevance Preferential use of highly filled composites for occlusal fillings is recommended.

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