Dredged Dam Raw Sediments Geotechnical Characterization for Beneficial Use in Road Construction

2021 ◽  
Vol 57 ◽  
pp. 81-98
Author(s):  
Abdelkader Larouci ◽  
Yassine Senhadji ◽  
Laid Laoufi ◽  
Amar Benazzouk
Keyword(s):  
Research Work ◽  
Chemical Properties ◽  
Road Construction ◽  
Mineralogical Composition ◽  
Organic Content ◽  
Experimental Program ◽  
Dredged Sediments ◽  
Standard Methods ◽  
X Ray ◽  
Alternative Material

The present research work aims to evaluate the feasibility of reusing raw dredged sediments from the Dam of Fergoug (northwestern Algeria) as an alternative material for road construction. These sediments were added to volcanic tuff from the quarry located near the village of Sidi Ali Cherif, in the town of Sig (northwestern Algeria), with contents of 5, 10, 15, 20 and 25% by total weight of tuff. To achieve this goal, sediments were extracted from Fergoug dam and an experimental program was carried out to study the possibility of valorizing these sediments to be used in road construction. The soils were subjected to a series of physical and chemical tests. Their physical properties, including the Atterberg limits, specific gravity, grain size distribution, and organic content were determined according to standard methods. Then, their chemical properties, including pH, elementary chemical composition using the X-ray fluorescence spectrometry and mineralogical composition identified by X-ray diffraction, were obtained by means of standard methods. The first experimental results from the tested formulations demonstrated the feasibility of reusing the valorized dredged sediments in road construction. Afterwards, the modified Proctor and ICBR tests were carried out, and the results obtained turned out to be quite satisfactory.

scholarly journals PHYSICAL AND CHEMICAL STUDIES OF OVERROOF ROCKS OF CLAY SHALES OF THE DZHERDANAK DEPOSIT

2021 ◽  
pp. 16-21
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Chemical Properties ◽  
Mineralogical Composition ◽  
Physical And Chemical Properties ◽  
X Ray ◽  
Clay Shales ◽  
Chemical Studies ◽  
Physical And Chemical ◽  
And Chemical Properties

The purpose of this study is study of the physical and chemical properties of the overburden of the Dzherdanak deposit. The chemical and mineralogical composition of the overburden of the Djerdanak deposit has been studied by the methods of X-ray and thermography, electron microscopy and infrared spectroscopy. The main phases are quartz, kaolinite and muscovite. The study of the fine structure of the rock under an electron microscope showed the homogeneity of the rock with pronounced uniform inclusions, which is preserved even after firing. Changes in the rock after firing at 1050 °C have been determined. The formation of mullite at this temperature has been established.

Immobilization of radioactive isotopes in fluorapatite matrices

2009 ◽  
Vol 1193 ◽  
Author(s):  
Elena Macerata ◽  
Piergiuseppe Innocente ◽  
Mario Mariani ◽  
Michele Galletta
Keyword(s):  
Nuclear Waste ◽  
Research Work ◽  
Chemical Properties ◽  
Radioactive Isotopes ◽  
Potential Candidate ◽  
Fluoride Salt ◽  
X Ray Diffraction ◽  
X Ray ◽  
Physical Chemical ◽  
Trivalent Cations

AbstractFluorapatite (Fap), Ca10(PO4)6F2, could be a potential candidate for the immobilization of radioactive isotopes thanks both to its physical-chemical properties and to the capability to incorporate mono-, di- and trivalent cations in its crystal structure. In this research work different preparation procedures able to incorporate in a fluorapatite matrix strontium in the form of nitrate or fluoride salt were considered. The experiments were performed by means of stable isotopes, as representative of the radionuclides contained in the nuclear fuel. Subsequently, the Sr-substituted fluorapatites (SrxFap), Ca10-xSrx(PO4)6F2, were characterized by X-ray diffraction, Raman spectroscopy, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The results suggest that the considered synthetic procedures could be reasonably applied to the confinement of the radionuclides contained in some types of nuclear waste. In order to avoid the presence of unreacted reagents in the products or the formation of undesired phases, an optimization of the synthetic procedures may be considered.

scholarly journals Mineralogical and Physico-Chemical Characterization of the Oraşu-Nou (Romania) Bentonite Resources

Minerals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 938
Author(s):  
Gheorghe Damian ◽  
Floarea Damian ◽  
Zsolt Szakács ◽  
Gheorghe Iepure ◽  
Dan Aştefanei
Keyword(s):  
Fine Fraction ◽  
Chemical Properties ◽  
Chemical Characterization ◽  
Colloidal Suspensions ◽  
Mineralogical Composition ◽  
Exchange Capacity ◽  
Absorption Capacity ◽  
Chemical Compositions ◽  
X Ray ◽  
Average Mass

The objective of this study is to describe the mineralogical composition and chemical properties of the Oraşu Nou bentonite, from northwestern Romania. For mineralogical determinations, the following were used: X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FR-IR), thermogravimetric analysis, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX). The chemical compositions and physical properties of the bentonites and bentonitized rocks were also determined. Calcium type montmorillonite is the predominant mineral in this deposit. Its average mass fraction is between 35% and 75%, reaching up to 95%. A small amount of halloysite and very fine cristobalite were also identified in the fine fraction. Quartz, feldspar, and kaolinite were identified as impurities. The average pH of natural bentonite is 6.2. Its cation exchange capacity (CEC) is in the lower-middle range for smectites at 45.89 cmol/kg, absorption capacity 43.58 mL/g, swelling degree 9.41%. Because of the high amounts and purity of montmorillonite, the valuable component mineral, the way is open to an easy refinement of this important resource. This way very high-quality colloidal suspensions can be obtained which can be used in the most modern applications of micro- and nanostructured materials.

scholarly journals The Antimicrobial Properties of Modified Pharmaceutical Bentonite with Zinc and Copper

Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1190
Author(s):  
Fotini Martsouka ◽  
Konstantinos Papagiannopoulos ◽  
Sophia Hatziantoniou ◽  
Martin Barlog ◽  
Giorgos Lagiopoulos ◽  
...  
Keyword(s):  
Antimicrobial Properties ◽  
Chemical Properties ◽  
Mineralogical Composition ◽  
X Ray Diffraction ◽  
Modified Bentonite ◽  
X Ray ◽  
Before And After ◽  
Antimicrobial Protection ◽  
Main Component ◽  
Phosphate Buffered Saline

Pharmaceutical grade bentonite, containing a high amount of montmorillonite, enriched with zinc (Zn) or copper (Cu) (ZnBent and CuBent, respectively) was used as the main component for the creation of formulations for cutaneous use and tested for their antimicrobial capacity. Bentonite (Bent) with added phenoxyethanol (PH) as a preservative and unmodified bentonite were used as control groups. The mineralogical composition, structural state, and physical or chemical properties, before and after the modification of the samples, were characterized utilizing X-ray Diffraction Analysis (XRD), Fourier-Transform Infrared Spectroscopy (FTIR) and X-ray Fluorescence (XRF) techniques, and Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM, SEM-EDS) analyses. In addition, the profile of zinc and copper concentration from two types of surfaces ZnBent and CuBent, and into Phosphate-Buffered Saline (PBS) are discussed. Finally, the formulations in the form of basic pastes were challenged against bacteria, molds, and yeasts, and their performance was evaluated based on the European Pharmacopeia criteria. The Cu-modified bentonite performed excellently against bacteria and yeasts, while the Zn-modified bentonite only showed great results against yeasts. Therefore, Cu-modified bentonite formulations could offer antimicrobial protection without the use of preservatives.

Characterization and Analyzation of Chitosan from Anadara granosa Shell

2016 ◽  
Vol 675-676 ◽  
pp. 463-466 ◽  
Author(s):  
Kanyakorn Teanchai ◽  
Nirun Witit-Anun ◽  
Surasing Chaikhun
Keyword(s):  
Crystalline Structure ◽  
Research Work ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Physical And Chemical ◽  
Anadara Granosa ◽  
And Chemical Properties ◽  
Chitosan Powder

This research work aims at characterize and analysis the physical and chemical properties of chitosan which derived from the Anadara granosa Shell. The physical and chemical properties have been also discussed in detail with X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR) Spectroscopy and Energy Dispersive X-Ray Fluorescence (EDXRF). The result showed that the XRD pattern indicated the Anadara granosa shell have crystalline structure of CaCO3 in Aragonite phase, while chitosan powder which extract from Anadara granosa shell has amorphous-crystalline structure. Another that, FTIR results confirmed the deeply formation of intermolecular bonding between the functional groups of the sample which the spectrum of FTIR indicate that the characteristic feature of Aragonite phase with the band of FTIR at ~1083 while the band at ~1653 were agree with chitosan polysaccharide. In addition, the EDXRF result were indicated that the concentrations of organic compounds in chitosan which extract from Anadara granosa shell have concentration is 33.581Wt% while the Anadara granosa shell have 0.033 Wt%. For Calcium (Ca) element the chitosan powder have concentration is 66.157 Wt% while the Anadara granosa shell have 99.850 Wt%.

3-D reconstruction of molecular shape from microcrystal thin sections

1983 ◽  
Vol 41 ◽  
pp. 748-749
Author(s):  
S. Cusack ◽  
J.-C. Jésior
Keyword(s):  
Three Dimensional ◽  
Molecular Shape ◽  
Biological Molecules ◽  
Fourier Space ◽  
Single Particles ◽  
Thin Sections ◽  
Standard Methods ◽  
X Ray ◽  
X Ray Crystallography ◽  
Dimensional Reconstruction

Three-dimensional reconstruction techniques using electron microscopy have been principally developed for application to 2-D arrays (i.e. monolayers) of biological molecules and symmetrical single particles (e.g. helical viruses). However many biological molecules that crystallise form multilayered microcrystals which are unsuitable for study by either the standard methods of 3-D reconstruction or, because of their size, by X-ray crystallography. The grid sectioning technique enables a number of different projections of such microcrystals to be obtained in well defined directions (e.g. parallel to crystal axes) and poses the problem of how best these projections can be used to reconstruct the packing and shape of the molecules forming the microcrystal.Given sufficient projections there may be enough information to do a crystallographic reconstruction in Fourier space. We however have considered the situation where only a limited number of projections are available, as for example in the case of catalase platelets where three orthogonal and two diagonal projections have been obtained (Fig. 1).

Cu Doped TiO2: Visible Light Assisted Photocatalytic Antimicrobial Activity and High Temperature Anatase Stability

2018 ◽  
Author(s):  
Snehamol Mathew ◽  
Priyanka Ganguly ◽  
Stephen Rhatigan ◽  
Vignesh Kumaravel ◽  
Ciara Byrne ◽  
...  
Keyword(s):  
Visible Light ◽  
Visible Light Irradiation ◽  
Density Functional ◽  
Anatase Phase ◽  
Sol Gel ◽  
Chemical Properties ◽  
Light Irradiation ◽  
Health Concern ◽  
Bacterial Inactivation ◽  
X Ray

Indoor surface contamination by microbes is a major public health concern. A damp environment is one potential sources for microbe proliferation. Smart photocatalytic coatings on building surfaces using semiconductors like titania (TiO<sub>2</sub>) can effectively curb this growing threat.<b> </b>Metal-doped titania in anatase phase has been proved as a promising candidate for energy and environmental applications. In this present work, the antimicrobial efficacy of copper (Cu) doped TiO<sub>2 </sub>(Cu-TiO<sub>2</sub>) was evaluated against <i>Escherichia coli</i> (Gram-negative) and <i>Staphylococcus aureus</i> (Gram-positive) under visible light irradiation. Doping of a minute fraction of Cu (0.5 mol %) in TiO<sub>2 </sub>was carried out <i>via</i> sol-gel technique. Cu-TiO<sub>2</sub> further calcined at various temperatures (in the range of 500 °C – 700 °C) to evaluate the thermal stability of TiO<sub>2</sub> anatase phase. The physico-chemical properties of the samples were characterised through X-ray diffraction (XRD), Raman spectroscopy, X-ray photo-electron spectroscopy (XPS) and UV-visible spectroscopy techniques. XRD results revealed that the anatase phase of TiO<sub>2</sub> was maintained well, up to 650 °C, by the Cu dopant. UV-DRS results suggested that the visible light absorption property of Cu-TiO<sub>2 </sub>was enhanced and the band gap is reduced to 2.8 eV. Density functional theory (DFT) studies emphasises the introduction of Cu<sup>+</sup> and Cu<sup>2+</sup> ions by replacing Ti<sup>4+</sup> ions in the TiO<sub>2</sub> lattice, creating oxygen vacancies. These further promoted the photocatalytic efficiency. A significantly high bacterial inactivation (99.9%) was attained in 30 mins of visible light irradiation by Cu-TiO<sub>2</sub>.

The Effect of Crosslinking Agents on the Properties of Type II Collagen Biomaterials

2021 ◽  
Vol 57 (4) ◽  
pp. 166-180
Author(s):  
Maria-Minodora Marin ◽  
Madalina Georgiana Albu Kaya ◽  
George Mihail Vlasceanu ◽  
Jana Ghitman ◽  
Ionut Cristian Radu ◽  
...  
Keyword(s):  
Research Work ◽  
Cartilage Tissue Engineering ◽  
Chemical Properties ◽  
Cartilage Regeneration ◽  
Type Ii Collagen ◽  
Biomechanical Properties ◽  
Cartilage Tissue ◽  
Cross Linking ◽  
Type Ii ◽  
Crosslinking Agents

Type II collagen has been perceived as the indispensable element and plays a crucial role in cartilage tissue engineering. Thus, materials based on type II collagen have drawn farther attention in both academic and research for developing new systems for the cartilage regeneration. The disadvantage of using type II collagen as a biomaterial for tissue repairing is its reduced biomechanical properties. This can be solved by physical, enzymatic or chemical cross-linking processes, which provide biomaterials with the required mechanical properties for medical applications. To enhance type II collagen properties, crosslinked collagen scaffolds with different cross-linking agents were prepared by freeze-drying technique. The present research work studied the synthesis of type II collagen biomaterials with and without crosslinking agents. Scaffolds morphology was observed by MicroCT, showing in all cases an appropriate microstructure for biological applications, and the mechanical studies were performed using compressive tests. DSC showed an increase in denaturation temperature with an increase in cross-linking agent concentration. FTIR suggested that the secondary structure of collagen is not affected after the cross-linking; supplementary, to confirm the characteristic triple-helix conformation of collagen, the CD investigation was performed. The results showed that the physical-chemical properties of type II collagen were improved by cross-linking treatments.

A Facile Synthesis of Cu2O and CuO Nanoparticles Via Sonochemical Assisted Method

2018 ◽  
Vol 15 (2) ◽  
pp. 209-213 ◽  
Author(s):  
Sathish Mohan Botsa ◽  
Ramadevi Dharmasoth ◽  
Keloth Basavaiah
Keyword(s):  
Diffuse Reflectance Spectroscopy ◽  
Cupric Oxide ◽  
Copper Acetate ◽  
Chemical Properties ◽  
Copper Oxide Nanoparticles ◽  
Reducing Agents ◽  
Sonochemical Method ◽  
Phase Purity ◽  
X Ray ◽  
Cuo Nps

Background: During past two decades, functional nanomaterials have received great attention for many technological applications such as catalysis, energy, environment, medical and sensor due to their unique properties at nanoscale. However, copper oxide nanoparticles (NPs) such as CuO and Cu2O have most widely investigated for many potential applications due to their wide bandgap, high TC, high optical absorption and non-toxic in nature. The physical and chemical properties of CuO and Cu2O NPs are critically depending on their size, morphology and phase purity. Therefore, lots of efforts have been done to prepare phase CuO and Cu2O NPs with different morphology and size. Method: The synthesis of cupric oxide (CuO) and cuprous oxide (Cu2O) NPs using copper acetate as a precursor by varying the reducing agents such as hydrazine sulphate and hydrazine hydrate via sonochemical method. The phase, morphology and crystalline structure of a prepared CuO and Cu2O NPs were investigated by X-ray diffraction (XRD), Fourier transform infrared (FTIR), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray (EDS) and UV-Visible Diffuse reflectance spectroscopy (DRS). Results: The phase of NPs was tuned as a function of reducing agents.XRD patterns confirmed the formation of pure phase crystalline CuO and Cu2O NPs. FTIR peak at 621 cm-1 confirmed Cu(I)-O vibrations, while CuO vibrations confirmed by the presence of two peaks at 536 and 586 cm-1. Further investigation was done by Raman, which clearly indicates the presence of peaks at 290, 336, 302 cm-1 and 173, 241 cm-1 for CuO and Cu2O NPs, respectively. The FESEM images revealed rod-like morphology of the CuO NPs while octahedral like shape for Cu2O NPs. The presence of elemental Cu and O in stoichiometric ratios in EDS spectra confirms the formation of both CuO and Cu2O NPs. In summary, CuO and Cu2O NPs were successfully synthesized by a sonochemical method using copper acetate as a precursor at different reducing agents. The bandgap of CuO and Cu2O NPs was 2.38 and 1.82, respectively. Furthermore, the phase purity critically depends on reducing agents.

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