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1

Tetracycline removal from water by adsorption on geomaterial, activated carbon and clay adsorbents

Ait-Hamoudi Souhila, Hamdi Boualem, Brendlé Jocelyne

Ecological Chemistry and Engineering. S

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2021

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Vol. 28, nr 3

303--328

EN

The use of antibiotics for breeding and for humans increased considerably in recent years, as a dietary supplement to enhance animal growth. This frequent use leads to the detection of residues in water and wastewater. Thus, the emergence of new strains of bacteria resistant to these antibiotics and, can lead to incurable diseases of livestock, and can lead to a possible transmission of these strains to humans. The purpose of this work is to develop new materials based on treated Maghnia clay, activated carbon, cement, and PVA polymer, named geomaterials. These materials were intended for the containment of hazardous wastes in landfills. The removal of tetracycline from aqueous solution was tested by adsorption onto synthesised geomaterials and their mineral constituents. Adsorption kinetics revealed that tetracycline was rapidly retained by GM and ATMa. This was confirmed by the relatively short equilibrium time of 30 min. The pseudo-second-order and intraparticle models well fitted the adsorption kinetic of the TC-adsorbent studied systems. It was noticed that the adsorption kinetic passes through several mechanisms, was demonstrated by the multi-linearity on the plot of qt against the square root of t. The adsorption capacity (Qa) of TC onto GM is pH-dependent. Indeed, Qa reaches a maximum value (Qa = 12.58 mg · g–1 at a very acidic pH of 2, then the adsorbed amount decreases to reach a minimum value at pH of 8, and for basic pHsQa increases up to 10 mg · g–1.

2

Investigation of the Physical, Mechanical and Aesthetic Characteristics of Terrazo Tiles Obtained from Different Rock Aggregates

Çoşkun Canberk, Rızaoğlu Tamer

Multidisciplinary Aspects of Production Engineering

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2020

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Vol. 3, Iss. 1

477--490

EN

Throughout history, people have covered the floors of the buildings with materials such as carpet, rock pieces, wood, mosaic, ceramic and tile according to the conditions of the day due to their desire to protect them from moisture, make them hygienic environment easy to clean and give an aesthetic appearance. The merging of mechanization with cement based materials with the industrial revolution in the 19th century has brought along the development of diversity and different production methods in these floor covering materials. One of these coating materials is terrazo tiles that form the subject of the current paper. Terrazo tiles are materials obtained by pressing the mortar obtained by mixing water, cement, marble powder and aggregate in certain proportions. Within the scope of this research, it was aimed to provide alternative raw materials to the tile body and to transform the rock pieces, which are found in waste form in natural stone workshops, into the economy. For this purpose, geomaterials collected from magmatic, metamorphic and sedimentary rocks cropped in the Kahramanmaraş-Antakya-Elazığ regions and natural stone workshops operating in Kahramanmaraş city, were classified according to their geological origins and aggregates of 4.75-12 mm were obtained with the help of jaw crushers and sieves. Tiles have been produced in accordance with the method of tile production from sized aggregates. The produced tiles were kept in the water pool for 28 days and surface controls were made. According to the physical and mechanical test results applied to the tile samples, water absorption by weight is 5.31-13.25%, bending strength 4.95-8.89 MPa, Böhme abrasion resistance 1.09-3.43 cm3 /50 cm2 , mass loss after freeze-thaw is observed to be in the range of 0.97-1.59%. On the other hand, the surface roughness of the tiles prepared with coarse rock aggregates was found to be relatively lower than the tile samples obtained with fine grained rock aggregates. The obtained results indicate that the geomaterials subject to the research can be used as an alternative raw material source in tile production and these raw materials will provide new benefits to the construction field.

3

Thermo-physical characteristics of acrylic-based building external isolation panels produced from different geological materials

Karataş M. Z., Rizaoğlu T.

Production Engineering Archives

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2018

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Vol. 21

12--19

EN

Here we describe a new type of environmentally sensitive insulation panels which can be used on exterior wall surfaces to minimize all the negative aspects of existing coating materials by taking advantage of natural rock properties. We investigate the decorative characteristics and insulation performance of this new product, obtained by applying materials from different lithologies to Expanded Polystyrene Surfaces (EPS). First, a mortar with 25% acrylic and 75% sand was applied to the EPS by a stripping method using sand size materials from various lithologies (granite, micaschist, basalt, quartzite, and pumice). To determine the optimum thickness, insulation panels containing plaster of 2, 4, 6, and 8 mm thickness were prepared for each lithology. Their thermal conductivity coefficient, bending and compressive strength were tested. Predictably, thermal conductivity coefficient yielded lowest values in 2 mm panels and highest in 8 mm panels for all lithologies. The bending strength also increased proportionaly with thickness. In the compressive strength tests, the highest values were measured for the 2 mm panels while relatively low values were obtained for the 4, 6 and 8 mm panels, except for the micaschist and basalt-based panels. As a result, basalt and pumice offer superior features in the three measured parameters, so, it is expected that different combinations of these two lithologies would offer positive features. In this context, considering its high fire resistance and low thermal conductivity coefficient perpendicular to the planar surface of muscovites, micaschist is the third lithology that can be utilized with the two materials mentioned above. Compared with previous materials, the products investigated in this study are cost effective because they reduce paint costs, application time and total building load. The geomaterials also have aesthetic appeal.

4

Description of hydraulic and strength properties of anisotropic geomaterials

Pietruszczak S., Pande G. N.

Studia Geotechnica et Mechanica

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2012

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Vol. 34, nr 3

3--16

EN

In this paper, a simple generalization of Darcy’s law is proposed for the description of hydraulic properties of anisotropic porous materials. The coefficient of permeability is defined as a scalar valued function of orientation. The principal directions of permeability are determined from a fabric descriptor specifying the distribution of average pore size. An example is provided for identification of material parameters, which is based on an idealized “pipe network model”. A procedure for defining the anisotropy in strength properties, which incorporates a conceptually similar approach, is also reviewed and an illustrative example is provided.

5

Warunki stanu granicznego dla ośrodków rozdrobnionych

Dołżyk K.

Budownictwo i Inżynieria Środowiska

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2011

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Vol. 2, no. 2

123-128

PL

W latach 60-tych ubiegłego wieku zaproponowano wiele warunkow stanu granicznego dla ośrodkow rozdrobnionych. Większość warunków uwzględnia wpływ pośredniego naprężenia głównego na wytrzymałość i przyjmuje liniową zależność wytrzymałości od wartości średniego ciśnienia. Przyjmując że wytrzymałość ośrodka rozdrobnionego nie zależy od pośredniego naprężenia głównego, wytrzymałość ośrodka rozdrobnionego może być określona warunkiem Coulomba-Mohra o dwoch parametrach: kohezji c i kącie tarcia wewnętrznego. Ze względu na swoją prostotę warunek Coulomba-Mohra jest najczęściej wykorzystywany w praktyce inżynierskiej.

EN

Many failure criteria were proposed for geomaterials in the sixties of the 20th century. In most of them the influence of middle main stress is neglected and linear influence of hydrostatic pressure on failure is assumed. The most popular and simplest is the Mohr-Coulomb criterion of failure with two material failure parameters: angle of friction and cohesion c. The Mohr-Coulomb criterion is most often used in engineering practice.

6

Sprężysto-plastyczny model materiałów geologicznych

Majewski S., Krzywoń R., Szojda L., Wandzik G.

Zeszyty Naukowe. Budownictwo / Politechnika Śląska

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2007

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z. 111

305-314

PL

Opisano prosty sprężysto-plastyczny model materiałowy, wzorowany na wcześniejszych modelach dla betonu opracowanych przez Willama i Warnke (1974) oraz Chena (1991). W artykule przedstawiono autorskie uogólnienie modelu na inne materiały określane ogólną nazwą materiałów geologicznych lub krótko geomateriałów. Zaproponowany matematyczny opis zachowania materiału należy zakwalifikować do modeli uproszczonych, które umożliwiają jednak bardziej realistyczny opis zachowania konstrukcji w trójwymiarowej przestrzeni, w porównaniu z wynikami otrzymywanymi w analizach wykorzystujących modele sprężyste.

EN

A simple, elasto-plastic material model for geological media is presented further on. It is based on the model, which was proposed for concrete by Willam and Warnke (1974), Chen (1991). In this paper, its' generalization for other geological materials is presented. Thus it is not enhanced model in the area of material modelling, but just an engineering proposal, which makes possible a little more realistic analysis of complex 3-D structural systems than the simplified, linearly elastic models do.