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1

Metal-organic frameworks for efficient drug adsorption and delivery

Hyjek Kornelia, Jodłowski Przemysław

Scientiae Radices

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2023

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Vol. 2, Iss. 2

115-189

EN

In recent years, the number of materials used as drug delivery systems (DDS) has increased dramatically. The widespread use of DDSs has improved both the safety and efficacy of therapy. The systems currently in use pose numerous drawbacks and require proper improvements. Although many modern materials are being developed, metal-organic frameworks (MOFs) deserve special attention. Thermal and chemical stability, high specific surface area, low toxicity, high biocompatibility, and great potential for modification are the main features enabling MOFs to be used as DDS. In this review, we describe MOFs, their structure, synthesis, and characterization, as well as drug loading, drug release kinetics, and bioassays. A critical approach is to outline the disadvantages as well as the limitations of MOFs and to identify areas that need to be studied more thoroughly. Nonetheless, the prospective nature of MOFs as DDS and potential adsorbents in overdose or poisoning is presented and highlighted.

2

Investigation of the effect of cyanidation after microwave roasting treatment on refractory gold/silver ores by characterization studies

Yoğurtcuoğlu Emine

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 1

art. no. 157487

EN

In this article, the efficiency of microwave pretreatment, which is an environmentally friendly, low-energy consuming method for recovery from refractory gold-silver ores, was investigated. The ore sample belonged to the oxidized Bolkardağ deposit, which contains carbonate (calcite, dolomite, smithsonite, hydrozincite), silicate (quartz, hemimorphite), sulfate (beudantite, plumbo-jarosite), and iron oxy/oxyhydroxide (hematite, limonite) minerals. Sulfur/sulfate-bearing silver and gold minerals are found either together with gangue minerals or in inclusions. Approximately 90% gold and 48% silver recovery efficiencies were achieved with the cyanide process after microwave preroasting from the ore. Additionally, the ore, heat treatment product, and waste samples were investigated by characterization studies. In these studies, bond structures, mineral content, sample mass losses, element percentage content differences, and mineral percentage content differences in the samples were determined. As a result, the microwave pretreatment application in cyanidation was presented as a new research topic in terms of its application in the valuable refractory content of this type of oxide.

3

Expectation properties of generalized order statistics based on the Gompertz-G family of distributions

Alharbi Yousef F., Fawzy Mohamad A., Athar Haseeb

Operations Research and Decisions

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2023

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Vol. 33, No. 4

1--14

EN

Gompertz-G family of distributions has been considered. The moment properties of generalized order statistics were studied and characterization results have been presented. Further, several examples and special cases were discussed. The results can be applied to many known distributions included in this family.

4

Improving optical and morphological properties of Mn-dopedZnO via Ar ion sputtering followed by high-temperature UHV annealing

Zehar Elhachemi, Ouerdane Abdallah, Chetti Boualem, Coruh Ali

Materials Science Poland

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2023

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Vol. 41, No. 2

325--338

EN

Using the ultrasonic spray pyrolysis technique, pure (ZnO) and manganese (4at%)-doped zinc oxide (ZnMnO) thin films were synthesized and treated with Ar+ sputtering in the UHV (ultra-high vacuum) system. In this regard, XRD (X-ray diffraction), XPS (X-ray photoelectron spectroscopy), PL (photoluminescence), and AFM (atomic force microscopy) techniques were applied to investigate the electronic and photonic properties of ZnO. XRD and XPS allowed us to identify the successful incorporation of Mn as a substitute for Zn, while PL and AFM images reveal a high tendency for crystalline grains on theZnMnO surface to aggregate to form small grains. However, bandgap narrowing, a redshift with considerable fluctuations in excitonic emission, and a perfect quenching of visible emission (400–640 nm) were observed. Investigations into defect-related emission in ZnMnO and ZnO compounds were conducted. The PL spectra of the prepared samples were measured and analyzed using Gaussian fitting. The PL of undoped ZnOexhibited an intense broad band with a peak at 550 nm. Two effects were shown to occur as a result of Mn doping: (i) a sharp quenching of self-activated PL with a progressive red-shift of the quenching’s spectral boundary; (ii) the appearance of a new emission band with a peak at 1.64 eV (756 nm), which dominates the PL spectrum and is noted in a band diagram; as well as a slight shift in the main line of ZnO, which is located at energy 3.275 eV (378.57nm).

5

Aerospace 3D textile preform analysis: experimental and mesomodeling

Saboktakin Abbasali, Izmir Hossein Safaei

Composites Theory and Practice

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2023

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R. 23, nr 3

118--122

EN

For the purpose of predicting how textile preforms affect the quality of the composite material and its performance, the stitched textile preform must be characterized. Experimental compaction analysis and finite element analysis of textile preforms are the main subjects of this paper. The formability parameters of a preform can be changed by the stitching process, according to research on the mechanical properties of preforms conducted during compression testing. The loaddeformation response, which is depicted in detail, had the greatest influence on preform deformation. Less fiber bundle undulation in the plane direction and more stitching thread undulation in the thickness direction were observed during compression of the stitched preform, whereas the stitching thread improved the resistance of the preform to compression loading.

6

Immobilization with Ca–Alg@gelatin hydrogel beads enhances the activity and stability of recombinant thermoalkalophilic lipase

Yildiz Dalginli Kezban, Atakisi Onur

Chemical and Process Engineering : New Frontiers

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2023

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Vol. 44, nr 1

art. no. e2

EN

This study aims at the immobilization and characterization of thermoalkalophilic lipases produced recombinantly from Bacillus thermocatenulatus BTL2 and Bacillus pumilus MBB03. For this purpose, immobilization of the produced enzymes in calcium-alginate@gelatin (Ca–Alg@gelatin) hydrogel beads, immobilization optimization and characterization measurements of the immobilized-enzyme hydrogels were conducted. Optimum temperature and pH values were determined for B. thermocatenulatus and B. pumilus MBB03 immobilized-enzyme hydrogels (60–70 °C, 55 °C and pH 9.5, pH 8.5). Thermal stability was determined between 65 °C and 60 °C of B. thermocatenulatus and B. pumilus MBB03 immobilized enzymes, respectively. The pH stability was determined between pH 7.0–11.0 at +4°C and pH 8.0–10.0 at +4 °C, respectively. In conclusion, the entrapment technique provided controlled production of small diameter hydrogel beads (~ 0:19 and ~ 0:29) with negligible loss of enzyme. These beads retained high lipase activity at high pH and temperature. The activity of Ca–Alg@gelatin-immobilized lipase remained relatively stable for up to three cycles and then markedly decreased. With this enzyme immobilization, it may have a potential for use in esterification and transesterification reactions carried out in organic solvent environments. We can conclude that it is one of the most promising techniques for highly efficient and economically competent biotechnological processes in the field of biotransformation, diagnostics, pharmaceutical, food and detergent industries.

7

Coupled electrical circuit method calculation with 3MA eddy current application for metal investigation

Ahmed Katia Sidi, Maouche Bachir, Gabi Yasmine, Wolter Bernd, Straß Benjamin

Przegląd Elektrotechniczny

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2022

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R. 98, nr 3

64--68

EN

This paper highlights the robustness of the semi analytical computation so-called ‘coupled circuit’ method for the simulation of the eddy current method integrated in the commercial non-destructive testing, 3MA equipment. For this purpose, semi-analytical development are carried out for calculation of voltage around eddy current- receiver coil, taking into account the skin depth of the sample. The challenge in the following is to reproduce the eddy current 3MA measuring quantities on conductive and ferromagnetic materials under several inspection situation. Furthermore, eddy current parameters will be underlined in impedance diagram varying the frequency and lift-off.

PL

W artykule podkreślono niezawodność półanalitycznych obliczeń, tak zwanej metody „obwodów sprzężonych”, do symulacji metody prądów wirowych zintegrowanej z komercyjnymi badaniami nieniszczącymi, sprzęt 3MA. W tym celu przeprowadza się półanalityczne opracowanie obliczania napięcia wokół cewki odbiorczej prądu wirowego z uwzględnieniem głębokości naskórka próbki. Wyzwaniem w dalszej części jest odtworzenie wielkości pomiarowych prądów wirowych 3MA na materiałach przewodzących i ferromagnetycznych w kilku sytuacjach kontrolnych. Ponadto parametry prądów wirowych zostaną podkreślone na wykresie impedancji, zmieniając częstotliwość i oderwanie.

8

Characterization of perlite powders from Izmir, Türkiye region

Aksoy Özay, Alyamaç Elif, Mocan Merve, Sütçü Mücahit, Özveren-Uçar Nihan, Özgür Seydibeyoğlu, M.

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 155277

EN

Perlite is an amorphous volcanic glass-type rock which is collected in open mines in various parts of the world. In this study, eight different perlite samples, supplied from the mines located in the Bergama, Izmir region, were used. The perlite samples were structurally, morphologically, and mineralogically characterized via a wide range of analytical techniques such as Thermogravimetric Analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) Surface Area Analysis, Optical Microscopy, Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), X-ray Fluorescence (XRF), and a liquid pycnometer. Platelet shaped-like structures were observed in the SEM analysis of the expanded perlites in contrast to the images of spongy or cracked expanded perlites reported in literature. The O-H bending and Si-O-Si vibrations (both asymmetric and symmetric stretching) of perlite structures were confirmed by FTIR. Highly amorphous phases with a rather low percentage of crystalline phases were observed by XRD. In the BET surface area analysis, expanded perlite materials exhibited higher surface area compared to unexpanded ones. A detailed characterization of perlite structures is essential as there is a significant potential to use these minerals in various biocomposite applications and it is useful to explain structure-property relationships in this class of materials.

9

Production of pumice-containing nanofibers by electrospinning technique

Kılıçer Ali

Materials Science Poland

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2022

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Vol. 40, No. 2

206--213

EN

The scope of the study involves identifying the optimal means to effectively use the electrospinning technique to obtain pumice-containing nanofibers. Nanofiber containing pumice in a solution was electrospun to obtain smooth, cylindrical, bead-free, and ultrafine nanomaterials. The study also analyzed the molecular [Fourier transform infrared spectroscopy (FTIR)], thermal [differential scanning calorimetry (DSC)], zeta potential, size, polydispersity index [dynamic light scattering (DLS)], and surface [scanning electron microscope (SEM)] parameters of the pumice-containing nanofibers having JP6 (applied voltage: 6 kV) and JP12 (12 kV) properties. While the distance (10 cm), flow rate (0.8 mL/h), and other parameters of the electrospinning process were fixed, two different voltages were applied to obtain the pumice-containing nanofiber. The average diameter of the nanoencapsulated pumice produced at 6 kV was defined as 98.6 nm in gelatin nanomats with 31.8 nm. The average diameter of the nanocapsule pumice produced under a 12 kV voltage was found to be 85.8 nm, and the average diameter of the nanomats (non–nanoencapsulated) was 35.2 nm. The average zeta potential values of the pumice-containing nanofiber were also determined in the nanosize range. The JP6 and JP12 PDI values were determined as 0.165 and 0.566, respectively. Peaks characteristic of pumices as defined in the literature were observed in the FTIR results, while DSC analysis results revealed strong endo- and exothermic peaks. As a result of this study, it has been proved that pumice can be reduced to nanosize with the electrospinning technique and it is nanoencapsulated in nanofiber. When the obtained pumice-containing nanofiber was examined, it was determined that the surface area of the nanofiber was large and resistant to thermal heat.

10

The Ability of Rhizopus stolonifer MR11 to Biosynthesize Silver Nanoparticles in Response to Various Culture Media Components and Optimization of Process Parameters Required at Each Stage of Biosynthesis

Khleifat Khaled, Alqaraleh Moath, Al-limoun Muhamad, Alfarrayeh Ibrahim, Khatib Rasha, Qaralleh Haitham, Alsarayreh Ahmad, Al Qaisi Yaseen, Hajleh Maha Abu

Journal of Ecological Engineering

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2022

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Vol. 23, nr 8

89--100

EN

One of the most important roles for nanotechnology concerns is the development of optimizable experimental protocols for nanomaterials synthesis. The formation of silver nanoparticles (AgNPs) was supported by Rhizopus stolonifer MR11, which was isolated from olive oil mill soil samples. The ability of R. stolonifer MR11 to biosynthesize silver nanoparticles in response to various components of different culture media was tested. Furthermore, the conditions under which the reducing biomass filtrate was obtained, as well as the conditions of the bio-reduction reaction of AgNO3 into AgNPs, were investigated. The fungal biomass filtrate of the strain Rhizopus stolonifer MR11 was capable of converting silver nitrate into AgNPs, as evidenced by the color change of the fungal filtrates. UV-Vis spectrophotometer, TEM, Zeta potential, Zeta sizer, FT-IR, and XRD analyses were used to characterize the AgNPs. TEM analysis revealed that the silver nanoparticles were 1–35 nm in size. R. stolonifer MR11 produced the maximum AgNPs when grown for 18 hours at 36 °C in media with starch and yeast extract as the sole carbon and nitrogen sources, respectively. The reducing biomass filtrate was obtained by incubating 5 g mycelial biomass in deionized water with a pH of 6 for 48 hours at 30 °C. The optimal reduction conditions of the biosynthesis reaction were determined by adding 1.0 mM AgNO3 to a pH 5 buffered mycelial filtrate and incubating it for 72 hours at 33 °C. The current study’s findings highlighted the importance of process parameters at each stage for optimal AgNPs biosynthesis.

11

Physico-Chemical Characterization of Leachate from the Moulay Abdallah Technical Landfill Center (Morocco)

Rhoualem Faïza, El Hadiri Hassane, Oukour Nabil, Taouil Hamid, Arouyaa Khalid, Ahmed Said Ibn

Journal of Ecological Engineering

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2022

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Vol. 23, nr 8

241--248

EN

The physico-chemical characterization of the leachate from the Technical Landfill Center (TLC) of Moulay Abdallah (MA) which is intended for the treatment of Household Waste (HW) and Waste Assimilated to Household Waste (HWA) as well as the elaboration of the results of the study that was carried out on the leachate from the Oum Azza (OA) Technical Landfill allowed comparing the leachate from two TLCs located in two different regions and exploited in two different ways. The parameters studied are Organic Matter (OM), Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD5), Total Kjeldahl Nitrogen (TKN) concentration, NH4+ ion concentration, conductivity, Suspended Solids (SS), Total Phosphorus (TP) and pH. The choice of these parameters comes down to their usefulness for the sizing of the leachate purification processes (PP) of the leachates of Moroccan typology, produced by the population of a coastal city. The results of the analyses show that the leachates from the two TLCs have almost the same physico-chemical characteristics. Depending on the method of management of the leachate (storage or direct discharge to the wastewater treatment plant (WWTP)), the evolution over time of these characteristics differed from one TLC to the other and all of the main leachate parameters from the TLC MA have all tended to increase over the time of operation. This is in contrast to the leachate parameters from the OA TLC, which all tended to decrease.

12

Extraction and Characterization of Silicon Dioxide from Volcanic Ash of Mount Sinabung, Indonesia: A Preliminary Study

Hasanah Moraida, Sembiring Timbangen, Sitorus Zuriah, Humaidi Syahrul, Zebua Fynnisa, Rahmadsyah

Journal of Ecological Engineering

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2022

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Vol. 23, nr 3

130--136

EN

The study was conducted on the extraction of volcanic ash from Mount Sinabung through the co-precipitation method to recover silicon dioxide (SiO2). The X-ray fluorescence (XRF) analysis showed that the SiO2 content in volcanic ash was 48.5%, and after extraction, it was 99.1%. The morphology shown by scanning electron microscope (SEM) indicated that SiO2 looks cleaner and tends to be the same size compared to the volcanic ash sample. The average particle size of volcanic ash and extracted SiO2 were 32.28571 ± 2.51259 and 12.97521 ± 0.60657 μm, respectively. The X-ray diffractometer (XRD) analysis showed that the crystal structure of the volcanic ash sample was quartz, maghemite, and cristobalite. Besides, the extracted SiO2 had an amorphous quartz crystal structure. The test conducted using Fourier transform infrared (FTIR) resulted in the absorption of 1095.57 cm-1 and 798.53 cm-1 for the Si‒O‒Si and Si‒OH groups which were the groups of siloxanes and silanols, respectively.

13

Structure and Dielectric Properties of V and Y Disorder Doped SrBi2Nb2O9 Ceramics

Afqir Mohamed, Elaatmani Mohamed, Zegzouti Abdelouahad, Tahiri Nabiha, Daoud Mohamed

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 4

1455--1458

EN

Y and V codoped SrBi2Nb2O9 ceramics, which have been characterized by XRD, FTIR and SEM techniques, were prepared through molten salt using NaCl-KCl medium. Through X-ray diffraction analysis, all prepared samples were matched by undoped SrBi2Nb2O9. The lattice parameters do not depend on the amount of dopants. Under the optimized experimental conditions, the compounds are composed of small crystallites of varying size and orientation, resulting in many micros train defects. FTIR spectra revealed that the dopant promotes a slight decrease in the 612 cm-1 band. A plate-like morphology was revealed by scanning electron microscopy, while Nyquist plots indicate non-Debye relaxation for all compounds. V and Y were incorporated into SrBi2Nb2O9 lattice in order to reduce dielectric loss tangent. Thus, the codoping increases the of SrB1.9Y0.1Nb1.95V0.05O9 (Y0.1V0.05) ceramic whereas, they were significantly decreased in the case of SrB1.8Y0.2Nb2O9 (Y0.2) ceramic. Y0.1V0.05 sample makes up the highest efficient charge transfer, followed by Y0.2 sample representing the lowest.

14

Simple steps for the detection and classification of different lamprophyric rocks: a case study from Greece

Kamvisis Ioanis-Nektarios G., Vasyukova Elena A.

Mineralogia

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2021

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Vol. 52, iss. 1

1--9

EN

This study aims to help non-expert geologists in locacating, classifying and analyzing lamprophyres, the exotic and complex rocks. The process includes three basic steps, a macroscopic study of the formation, petrographic microscopy and lastly whole-rock and trace element analyses of the samples. Fourteen Greek lamprophyric rocks with distinct characteristics were used. Conventional lamprophyres were considered along with rarer alkali minettes, meta-lamprophyres, lamproschists, appinites and para-lamproites.

15

Characterization of a static expansion standard for calibrating medium and high vacuum pressure gauges

Duarte Franco Jonathan Javier, Villamizar Mora Carlos Mauricio, García Sánchez Carlos Eduardo

Metrology and Measurement Systems

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2021

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Vol. 28, nr 3

593--604

EN

The Centro de Desarrollo Tecnológico del Gas developed a static expansion system to enable the calibration of medium and high vacuum pressure gauges in Colombia. The system can generate pressures between 0.1 Pa and 100 kPa. The characterization tests included the evaluation of pressure stability and desorption rate, a trueness test, and the analysis of the uncertainty budget of the calibration result. The pressure stability test was successfully completed and showed the positive effect of baking on the final pressure in the system. The trueness test allowed concluding that the calibration results with the system are comparable with those obtained with a reference meter traceable to a national metrology institute. The uncertainty budget analysis indicated the dominance of the pressure of the unit under calibration and of the initial pressure in the small tank in different pressure ranges on the uncertainty of the result. A comparison with a Monte Carlo simulation led to the conclusion that in this situation, the GUM (Guide to the Expression of Uncertainty in Measurement) method is not ideal for estimating the uncertainty of the results.

16

Characterization study of polyAMPS@BMA core-shell particles using two types of RAFT agents

Shah Nasrullah, Khan Zubair Ullah, Hussain Manzoor, Rehan Touseef, Khan Abbas

Materials Science Poland

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2021

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Vol. 39, No. 2

200--208

EN

The study and application of reversible addition-fragmentation chain transfer (RAFT) polymerization have been widely reported in the literature because of its high compatibility with numerous monomers, reaction conditions, and low polydispersity index. The effect of RAFT agents on the characteristics of the final product is greatly needed to be explored. Our present study aimed to compare the influence of two different types of RAFT agents on the characteristics of the water-soluble polymer (2-acrylamido-2-methylpropane sulfonic acid) (polyAMPS) and their polyAMPS@butyl methacrylate (BMA) core-shell particles. Different analytical techniques including scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were used to ascertain the final morphological, structural, and thermal properties of the resultant products. It was found that RAFT agents have shown a clear influence on the final properties of the resultant polyAMPS and their core-shell particles such as particle size, shape, size distribution, and thermal behavior. This study confirms that RAFT agents can control the final properties of the polymers and their core-shell particles.

17

Characterization of Physical, Chemical and Mechanical Properties of Sri Lankan Coir Fibers

Dharmaratne Prasad Dhammika, Galabada Harsha, Jayasinghe Randika, Nilmini Renuka, Halwatura Rangika Umesh

Journal of Ecological Engineering

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2021

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Vol. 22, nr 6

55--65

EN

This study was carried out to determine the characterization of brown coir fiber which is used as a potential reinforcement in polymer composites. The fiber is extracted from the husk of the coconut seeds which are collected in Sri Lanka. Anyhow the above-mentioned characterization can hardly be seen when it comes to the Sri Lankan context. Since the evaluation of their physical, mechanical, and chemical properties are significant before commencing the material development process and applications for this fiber. Several testing were carried out to evaluate the above-mentioned properties. There, the functional groups of coir fiber were obtained by Fourier Transform Infrared analysis and Crystallinity Index and Crystallite size were determined by X-ray diffraction analysis. The surface morphology and cross-sectional features were investigated through Scanning Electron Microscopy. The thermo-gravimetric method was adopted to study the thermal stability of coir fiber. The density and diameter of coir fiber were measured utilizing pychometric method and optical microscope respectively. Tensile strength was measured using an electronic tensometer and then find out the tensile strength, modulus of elasticity, and elongation at breaking point. The average density of brown coir fibers was 1.018 g/cm3 and average diameters were 0.30 mm. The Crystallinity Index and the crystal-line size were 37.28% and 0.4331 nm respectively. Ultimate tensile strength, Young’s modulus, and Elongation of the coir fiber were ranging from 94–159 MPa, 1.2–1.8 GPa, and 21–67%, respectively.

18

Analysis of Optimum Temperature and Calcination Time in the Production of CaO Using Seashells Waste as CaCO3 Source

Dampang Sarah, Purwanti Endah, Destyorini Fredina, Kurniawan Setyo Budi, Abdullah Siti Rozaimah Sheikh, Imron Muhammad Fauzul

Journal of Ecological Engineering

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2021

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Vol. 22, nr 5

221--228

EN

Seashells waste is abundant in coastal area, especially in the locations where fisheries are a major occupation. This abundant resource of seashells opens a new opportunity further utilization. Seashells waste is a source of CaCO3, which may be converted into CaO via the calcination process. This study analyzed the characteristics of the CaO produced via calcination process at different temperature and calcination time. The calcination process was carried out at a temperature of 800°C, 900°C, and 1000°C with variation of 2, 3, and 4 hours in time. The Fourier transform infrared spectroscopy (FTIR) result showed that the spectrum of 2513 cm-1 as an indication of the C-H group containing CaO appearing after calcination. The FTIR results suggest that the calcination time did not gave major alteration to the functional groups. The results of X-ray diffraction (XRD) analysis showed that CaO laid at the angle of 58.1° and 64.6°. Scanning Electron Microscopy–Energy Dispersive X-Ray Spectroscopy (SEM-EDS) results showed that the most significant compositional outcome after the calcination process was Ca and O at all temperatures and calcination times. All calcined seashells showed rough surface and irregular shape particles. The result of a Thermogravimetric analysis (TGA) suggested that the highest mass alteration occurred at a temperature of 800°C with 78 mins of calcination time.

19

Preparation and evaluation of conductive polymeric composite from metals alloys and graphene to be future flexible antenna device

Abdelrahman Ameen, Erchiqui Fouad, Nedil Mourad

Advances in Materials Science

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2021

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Vol. 21, nr 4(70)

34--52

EN

Every year hundreds of serious accidents and catastrophic are accompanied by mining sector services as disaster, flooding, and demolition. To reduce the severity of the results such as high death numbers, lost communication inner and out mining, we have to find an easy way to improve communication means during that problems. In this paper, we reach out to fabricate durable, flexible, and wearable chaps, in addition to an easier carrier with highly efficient receiving and sending a signal at 2.4 GHz broad wide band. By doping a bunch of unique conductive metals (silver, copper, and gallium indium alloy) assembled on Graphene, its integration inside Polydimethylsiloxane to be future applicable antenna. Furthermore, we studied the physical and electric properties of a composite including Electrochemical Impedance properties (EIS), cyclic voltammetry (CV), and its thermal stability chip (DSC), as well as, using Transmission electron microscopy (TEM), and, scanning electron microscopy (SEM) techniques to clarify the surface morphology of fabricated materials. In addition to various measurements had been carried out such as Ultraviolet-visible, inductively coupled plasma (ICP) spectroscopy, and Energy-dispersive X-ray spectroscopy (EDX) to reinforce and elucidate the solid-state of ions inside fabricated Antenna. On the other hand, throughout stress-strain for the stretchability of fabricated is expanded to 30% of its original length, in addition to thermal stability reached to 485°C compared to pure PDMS substrate, with enhancing electric conductivity of composite ship.

20

Environmental protection against acid mine drainage (AMD) testing of sulphide mining waste enrichment of the Chaabet-El-Hamra mine (Algeria)

Benabbes Lamia, Bounouala Mohamed

Mining Science

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2020

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Vol. 27

323--335

EN

The mining waste from the Chaabet-El-Hamra mine contains sulfides such as pyrite (FeS2), galena (PbS) and chalcopyrite (CuFeS2) Which pose a threat to the environment. Sulphide minerals under the effect of oxygen and in the presence of water cause a phenomenon of acid mine drainage. Samples taken at the site of the sulphide mine waste at the Chaabet El Hamra mine and subsequently subjected to chemical analyzes offered an average sulfur content of 9%. X-ray diffractometer analyzes confirm the presence of a considerable inclusion of pyrite containing secondary minerals of sphalerite, and galena. To do this, the tests were directed to an environmental desulphurization process by flotation of the pyriterich fraction with depression of the low sulfur mineralogical matrix containing heavy metals of zinc and lead.