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Impact of g-Load Shift on Temporal Expression Pattern of Apoptosis-linked Proteins in the Rat Mammary Gland

of proapoptotic proteins during the pregnancy-to-lactation transition in a mammary gland of an experimental animal model. Therefore, in the present investigation, we extended our preceding study to quantify the temporal distribution of apoptosis-related proteins, namely Cleaved Caspase-3 (CC-3), Tumor Protein p53 (p53), and vitamin D receptor (VDR) in the mammary tissue harvested from rats exposed to HG during the periparturient period employing quantitative immunohistochemistry. Methods Animals and Treatment Condition The research approval, experimental

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Damage detection in composite laminates aeronautics structures through accelerometers network

Damage detection in composite laminates aeronautics structures through accelerometers network

Over the past twenty years, the increase of use of structural materials in Aerospace is due to many reasons. While the properties of metallic materials are mastered, the risk behavior of composite materials requires monitoring of the structure. That's why many methods of non-destructive testing (NDT) have been implemented and applied for the evaluation of defects in composites.

The purpose of our research is the development of a new NDT tool for detecting delamination damages in aircraft's structures. The principle diagnostic is based on the application of a reproducible impact wave on a composite panel and its propagation trough an accelerometer sensor network. The presence of defects will be identified by the temporal and frequency response change compared to calibrated reference recorded before the damage.

Therefore, in this paper an experimental study of impact behavior of a composite laminate structure will be presented. The panel is made from a guarded composite long carbon fiber laminate. In the study, the shock propagation wave induced in the materials will take into account the fiber orientation (0°, 45°, 90°, -45°) and plies arrangement (plies stacking sequence of tilt-up). First results of this new NDT for detecting damages of an aircraft structure composite demonstrate the wide possibilities of this technique.

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Musculoskeletal Outcomes from Chronic High-Speed High-Impact Resistive Exercise

Introduction Musculoskeletal changes to chronic exercise offer a temporal framework for which to anticipate strength improvements and/or attenuation of in-flight losses from exercise hardware and/or protocols. Temporal changes refer to the rate and magnitude of adaptations over time, which help formulate training strategies to limit in-flight strength losses and thereby optimize long-term musculoskeletal health for long-term exposure to microgravity ( Fleck and Kraemer, 2014 ). Two 60-day bed rest studies assessed temporal adaptations to concurrent exercise

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Improvement of bio-compatible AZ61 magnesium alloy corrosion resistance by fluoride conversion coating

, H. Microstructures and Corrosion Properties on Fluoride Treated Magnesium Alloys. Materials transactions 2008 , 49, 1042-1047. 15. Avedesian, M. M., Baker, H. ASM Specialty Handbook: Magnesium and Magnesium Alloys 1999 , 314. 16. Yokel, R. The toxicology of aluminum in the brain: a review, Neurotoxicology 2000 , 21, 813-28. 17. Costantino, D. G., et al. Assessment of in vitro temporal corrosion and cytotoxicity of AZ91D alloy, Journal of Materials Science: Materials in Medicine 2012 , 23, 2553-2562. 18. Zhang, S. Biological and

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ANALYSIS OF OPERATION OF ARCH FRICTIONAL JOINT LOADED WITH THE IMPACT OF FREELY FALLING MASS

Abstract

Yielding support, commonly applied to secure dog headings, is made of carrying elements in the form of steel frames and friction props. Yielding capacity of this support is realized in frictional joints, which due to their geometry can be divided to straight and arch joints. Occurring in steel frames arch frictional joints are characterized with more complex loading state than straight joints used in friction props. In the article, there is presented an analysis of the state of stress and deformation of the arch frictional joint, which was carried out on the model of these joints using finite element method. The scope of the analysis included two methods of loading of arch frictional joint, namely its axial compression and bending. In both cases, joints were loaded dynamically with the impact of freely falling mass. Arch joints with and without passive pressure were submitted to an axial compression. Physical model of the frictional joint was developed on the basis of a system applied during the stand tests. To solve mathematical model an explicit integration method was used. As a result of analyses carried out, temporal courses of force transmitted through the frictional joint, and displacements of section sliding down were determined. On the basis of the temporal courses, dependences between maximum value of force transmitted through the frictional joint and the height from which the impact mass falls down were determined. Distributions of reduced stresses in elements of frictional joint were also determined and the state of deformation was described. In order to emphasize the difference between straight and arch frictional joints, also an analysis of internal forces in arch frictional joint depending on its geometrical parameters without and with passive pressure was presented.

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The Use of a Unipore Diffusion Model to Describe the Kinetics of Methane Release from Coal Spoil in the Longwall Environment

Abstract

The unipore methane diffusion model based on the solution of the second Fick’s law describes effectively the kinetics of methane release from coal grains. The knowledge of the model describing the kinetics of methane release from coal, the coalbed methane content, the sorption isotherm, the effective diffusion coefficient and the coal particle size distribution, enables the calculation of the volume of methane which is released from the coal spoil as a function of time. These assumptions became the basis for building the software that enables the analysis of methane emissions from coal during the longwall mining. Simulations were performed to determine the temporal and spatial methane inflow to the longwall. The share of methane emission from coal grains (taking into account both the emission kinetics and mass participation) of various classes has been analyzed. The results of the analysis showed that the methane from the small grains, in particular less than 0.1 mm in size, prevails. The mass fraction of these grains in the total weight does not exceed 5%. For the typical parameters determining the mining, geological and technological conditions of methane emissions at different moments of time and position of the longwall were determined.

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Geostatistical analysis of space variation in underground water various quality parameters in Kłodzko water intake area (SW part of Poland)

: Geostatistics for spatio-temporal analysis of hydrological events and environmental problems (13.04.2015). Geophysical Research Abstracts, Vol. 17, EGU2015-15693-2, 2015 EGU General Assembly 2015. [12] NAMYSŁOWSKA-WILCZYŃSKA B., Geostatistical studies of space-temporal variation in selected quality parameters in Kłodzko water supply system (SW part of Poland), Journal of Geological Resource and Engineering, 2015, Vol. 3, No. 2, USA, 57-81. [13] NAMYSŁOWSKA-WILCZYŃSKA B., Space-Temporal Variation in Underground Water Some Quality Parameters in

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Geostatistical modeling of porosity data in ‘oba’ field, onshore Niger Delta

. World Appl Sci J 18(1), pp.135–141. [4] Karatas, B.S., Camoglu G., Olgen M. (2013): Spatio-temporal analysis of the depth and salinity of the groundwater using geostatistics integrated with GIS, the Menemen Irrigation System, Western Turkey. Int J Environ (Ekoloji) 22(86), pp.36-47. [5] Doust, H., Omatsola, M. (1990): Petroleum geology of the Niger delta. Geological Society, London, Special Publications , 50, pp.365–365. [6] Whiteman, A (1982): Nigeria: its Petroleum Geology, Resources and Potential. Graham and Trotman, London. [7] Stacher

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On the Dynamic Response Prediction at the Full-Scale Test of Aircraft Component

Sensors . Amsterdam & Boston: Elsevier Academic Press, 2008. [17] G. C. Goodwin and R. L. Payne, Dynamic System Identification: Experiment Design and Data Analysis . Academic Press, 1977 [18] S. A. Billings, Nonlinear System Identification: NARMAX Methods in the Time, Frequency, and Spatio-Temporal Domains . Wiley, 2013. https://doi.org/10.1002/9781118535561 [19] T. P. Gialamas, D. A. Manolas, and D. T. Tsahalis, “Predicting the Dynamic Behaviour of a Coupled Structure Using Frequency-Response Functions,” Journal of Aircraft , vol. 39, issue 1, pp

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Analysis of urbanization impact on changes in river discharge – a case study of the Biała river catchment

, New York 2007. [18] NASA Landsat Program, 1972-2011: ETM+, TM, MSS scenes, USGS, Sioux Falls. [19] NASH J., SUTCLIFFE J., River flow forecasting through conceptual models , Part 1. A discussion of principles , J. Hydrol., 1970, 10, 282-290. [20] OLANG L.O., FÜRST J., Effects of land cover change on flood peak discharges and runoff volumes: model estimates for the Nyando River Basin , Kenya, Hydrol. Process, 2010, 25, 80-89. [21] OLANG L., KUNDU P., BAUER T., FÜRST J., Analysis of spatio-temporal

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