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D. Wilk-Kołodziejczyk, A.S. Kluska-Nawarecka, K. Regulski, W. Adrian and K. Jaśkowiec

Abstract

The aim of this work was to propose a methodology supporting the task of collecting the comparative data on studies of the mechanical properties of ADI. Collecting of research data is an important step in the process of finding the optimum design solutions for newly made products - experimental data allow us properly calibrate the manufacturing process of ADI to let the final product achieve the required properties. Parameters of the ADI production process, i.e. the time and temperature of austenitising and austempering, as well as the alloying elements added to ductile iron affect the ADI properties. The design process can use research data collected, among others, from the Web. As stated in the article, the process of data acquisition can be supported by semantic technologies, including ontologies which are descriptive logic formalism.

Open access

B. Pawłowski, P. Bała and R. Dziurka

Abstract

Dilatometry is the most commonly method of producing CCT diagrams and analyzing phase transformations during cooling (as well as transformations during heating) and it permits the real-time monitoring of the extent of reaction in terms of dimensional changes due to phase transformation. All modern dilatometers are fitted with computerised systems which collect dimensional change signals versus temperature to plot a dilatometric curve and also to calculate and plot the derivative of the relative dimensional change with respect to temperature. Unfortunately, elaborated by dilatometers manufacturers software, in many cases could lead to wrong interpretation of phase transformations during cooling.

Open access

R. Kaczmarek and R. Krawczyk

Abstract

Basic factors which have an influence on conducting manual ultrasonic testing of joints in the welded constructions are presented in the following article. These factors are specified on the base of the guidelines referring to conditions and methods of carrying out examinations which are currently in force in the following standards PN-EN ISO 17640 and PN-EN ISO 22825. Due to the vastness of subject of ultrasonic testing the main aim of the following article is to collect all important information which relates to design and manufacture of constructions and has a key influence on the following examinations.

Open access

Xuebang Wu and Changsong Liu

Abstract

The general trend in soft matter is to study systems of increasing complexity covering a wide range in time and frequency. Mechanical spectroscopy is a powerful tool for understanding the structure and relaxation dynamics of these materials over a large temperature range and frequency scale. In this work, we collect a few recent applications using low-frequency mechanical spectroscopy for elucidating the structural changes and relaxation dynamics in soft matter, largely based on the author’s group. We illustrate the potential of mechanical spectroscopy with three kinds of soft materials: colloids, polymers and granular systems. Examples include structural changes in colloids, segmental relaxations in amorphous polymers, and resonant dissipation of grain chains in three-dimensional media. The present work shows that mechanical spectroscopy has been applied as a necessary and complementary tool to study the dynamics of such complex systems.

Open access

Mojtaba Maghrebi, Claude Sammut and Travis S. Waller

methodology for collecting, classifying, and analyzing Canadian construction court cases”, Canadian Journal of Civil Engineering 34, 177-188. [10] Chen, J. H. and Hsu, S. C. (2007), “Hybrid ANN-CBR model for disputed change orders in construction projects”, Automation in Construction 17, 56-64. [11] Cheng, M. Y., Tsai, H. C. and Liu, C. L. (2009) “Artificial intelligence approaches to achieve strategic control over project cash flows”, Automation in Construction 18, 386-393. [12] Cheng, T. M. and Yan, R. Z. (2009

Open access

R. Kowalik

, K. Mech, P.R. Żabiński, Electrochemical deposition of CdS thin films from acid solutions. Rudyi Metale Nieżelazne 57 (9), 586-591 (2012). [25] M.S. Kazacos, B. Miller, Studies in selenious acid reduction and CdSe film deposition. Journal of The Electrochemical Society 127 (4), 869-873 (1980). [26] G. Pezzatini, F. Loglio, M. Innocenti, M.L. Foresti, Selenium(IV) electrochemistry on silver: A combined electrochemical quartz-crystal microbalance and cyclic voltammetric investigation. Collect Czech Chem C 68 (9), 1579-1595 (2003). [27] R. Kowalik, K

Open access

Chunfei Li, Virgil Solomon, Marjan Moro, Chad Welsh, Tyler McCauley, Michael Bauer and Joseph Cupo

Abstract

In an effort to synthesize doped ZnO nanowires, SiOx nanowires were obtained accidently. In the experiment, mixed powders containing chemicals such as ZnO, graphite, Ga2O3, and In2O3 were placed in the center of a tube furnace, where the temperature was set to 1200 °C and the vacuum was approximately 27 Pa. Silicon wafers were placed around the vicinity of the furnace exit to collect the expected nanomaterials. After prolonged heating, grey layers were found on top of one wafer located inside the furnace. The layer showed no adhesion to the substrate. Characterization by using Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), and Energy Dispersive X-ray Spectroscopy (EDS) revealed that this layer consisted of SiOx nanowires. Formation of Si-containing liquid drop and the subsequent growth of SiOx nanowires out of it are suggested as the growth mechanism.

Open access

K. Ravindranadh and M.C. Rao

Abstract

During recent decades, magnetic and semiconductor nanoparticles have attracted significant attention of scientists in various fields of engineering, physics, chemistry, biology and medicine. Fe3+ doped PVA capped CdTe nanoparticles were prepared by co-precipitation method and characterized by powder X-ray diffraction, SEM, TEM, FT-IR, optical, EPR and PL techniques to collect the information about the crystal structure, coordination/local site symmetry of doped Fe3+ ions in the host lattice and the luminescent properties of prepared sample. Powder XRD data revealed that the crystal structure belongs to a cubic system and its lattice cell parameters were evaluated. The average crystallite size was estimated to be 8 nm. The morphology of prepared samples was analyzed by using SEM and TEM investigations. Functional groups of the prepared sample were observed in FT-IR spectra. Optical absorption and EPR studies have shown that on doping, Fe3+ ions enter the host lattice in octahedral site symmetry. PL studies of Fe3+ doped PVA capped CdTe nanoparticles revealed UV and blue emission bands. CIE chromaticity coordinates were also calculated from the emission spectrum of Fe3+ doped PVA capped CdTe nanoparticles.

Open access

Zbigniew Muszyński and Jarosław Rybak

Abstract

In many cases of monitoring or load testing of hydrotechnical structures, the measurement results obtained from dial gauges may be affected by random or systematic errors resulting from the instability of the reference beam. For example, the measurement of wall displacement or pile settlement may be increased (or decreased) by displacements of the reference beam due to ground movement. The application of surveying methods such as high-precision levelling, motorized tacheometry or even terrestrial laser scanning makes it possible to provide an independent reference measurement free from systematic errors. It is very important in the case of walls and piles embedded in the rivers, where the construction of reference structure is even more difficult than usually. Construction of an independent reference system is also complicated when horizontal testing of sheet piles or diaphragm walls are considered. In this case, any underestimation of the horizontal displacement of an anchored or strutted construction leads to an understated value of the strut’s load. These measurements are even more important during modernization works and repairs of the hydrotechnical structures.

The purpose of this paper is to discuss the possibilities of using modern measurement methods for monitoring of horizontal displacements of an excavation wall. The methods under scrutiny (motorized tacheometry and terrestrial laser scanning) have been compared to classical techniques and described in the context of their practical use on the example hydrotechnical structure. This structure was a temporary cofferdam made from sheet pile wall. The research continuously conducted at Wroclaw University of Science and Technology made it possible to collect and summarize measurement results and practical experience. This paper identifies advantages and disadvantages of both analysed methods and presents a comparison of obtained measurement results of horizontal displacements. In conclusion, some recommendations have been formulated, which are relevant from the point of view of engineering practice.

Open access

Mieczysław Chalfen, Beata Głuchowska and Leszek Pływaczyk

Abstract

Groundwater table levels in a river valley depend, among other factors, on meteorological and hydrogeological conditions, land use and water levels in watercourses. The primary role of a watercourse is to collect surface and groundwater, and it becomes an infiltrating watercourse at high water levels. Changes in groundwater levels and the range of these changes depend chiefly on the shape, height and duration of the flood wave in the river channel.

The assessment of flood wave impact on groundwater was based on long-term measurements of groundwater levels in the Odra valley and observations of water levels in the river channel. Simulations were performed with the use of in-house software FIZ (Filtracja i Zanieczyszczenia; Filtration and Contamination), designed for modelling unsteady water flows within a fully saturated zone. A two-dimensional model with two spatial variables was employed. The process of groundwater flow through a porous medium, non-homogeneous in terms of water permeability, was described with Boussinesq equation. The equation was solved with the use of finite element method. The model was applied to assess groundwater level fluctuations in the Odra valley in the context of actual flood waves on the river.

Variations in groundwater table in the valley were analysed in relation to selected actual flood water levels in the Odra in 2001-2003 and 2010. The period from 2001 to 2003 was used to verify the model. A satisfactory agreement between the calculated and the measured values was obtained. Based on simulation calculations, it was proved that flood waves observed in 2010 caused a rise in groundwater table levels in a belt of approximately 1000 metres from the watercourses. It was calculated that at the end of hydrological year 2009/2010, the highest growths, of up to 0.80 m, were observed on piezometers located close to the Odra river channel. The passage of several flood waves on the Odra caused an increase of subsurface retention by 3.0% compared to the initial state.