Search results for: photoelectron spectroscopy

Authors: Yi-Hao Pai, Wen-Feng Chen

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The planting area of Pomelo in Hualien, Taiwan amounts to thousands of hectares. Especially in the blooming season of Pomelo, it is an important producing area for Pomelo honey, and it is also a good test field for promoting the "Under-forest Economy". However, in the current Pomelo garden planting and management operations, the large amount of agricultural waste generated by the pruning of the branches causes environmental sanitation concerns, which can lead to the hiding of pests or the infection of the Pomelo tree, and indirectly increase the health risks of bees. Therefore, how to deal with the pruning of the branches and avoid open burning is a topic of social concern in recent years. In this research, afeasibility study evaluating energy conversion efficiency through agricultural waste gasification from the Pomelo garden, Taiwan, is demonstrated. we used a high-temperature gasifier to convert the pruning of the branches into syngas and biochar. In terms of syngas composition and calorific value assessment, we use the biogas monitoring system for analysis. Then, we used Raman spectroscopy and electron microscopy (EM) to diagnose the microstructure and surface morphology of biochar. The results indicate that the 1 ton of pruning of the branches can produce 1797.03m3 of syngas, corresponding to a calorific value of 9.1MJ/m3. The main components of the gas include CH4, H2, CO, and CO2, and the corresponding gas composition ratio is 16.8%, 7.1%, 13.7%, and 24.5%. Through the biomass syngas generator with a conversion efficiency of 30% for power generation, a total of 1,358kWh can be obtained per ton of pruning of the branches. In the research of biochar, its main characteristics in Raman spectroscopy are G bands and D bands. The first-order G and D bands are at 1580 and 1350 cm⁻¹, respectively. The G bands originates from the in-plane tangential stretching of the C−C bonds in the graphitic structure, and theD band corresponds to scattering from local defects or disorders present in carbon. The area ratio of D and G peaks (D/G) increases with the decrease of reaction temperature. The larger the D/G, the higher the defect concentration and the higher the porosity. This result is consistent with the microstructure displayed by SEM. The study is expected to be able to reuse agricultural waste and promote the development of agricultural and green energy circular economy.

Keywords: agricultural waste, gasification, energy conversion, pomelo garden

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Authors: Fakhreldin O. Suliman, Alia H. Al-Battashi

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This work explored the interaction of three different imidazoline drugs, naphazoline nitrate (NPH), oxymetazoline hydrochloride (OXY) and xylometazoline hydrochloride (XYL) with two different synthesized cucurbit[n]urils CB[n], cucurbit[7]uril (CB[7]) and cucuribit[8]uril (CB[8]). Three binary inclusion complexes have been investigated in solution and in the solid state. The solid complexes were obtained by lyophilization, whereas the physical mixtures of guests and hosts at a stoichiometric ratio of 1:1 were obtained for each drug. 1HNMR, electrospray ionization mass spectrometry (ESI-MS), and matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry was used to study the complexes prepared in aqueous media. The lyophilized solid complexes were characterized by Fourier transform-infrared spectroscopy (FT-IR), powder X-ray diffractometry (PXRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). MS, FT-IR and PXRD experimental results established in this work reveal that NPH, OXY and XYL molecules form stable inclusion complexes with the two hosts. The TGA and DSC confirmed the enhancement of the thermal stability of each drug and the production of a thermally stable solid complex. The 1HNMR has shown that the protons of the guests faced shifting in ppm and broadening of their peaks upon the formation of inclusion complexes with the selected CB[n]. The aromatic protons of the guest exhibited the highest changes in the chemical shifts and shape of the NMR peaks, suggesting their inclusion into the cavity of the CB[n]. The diffusion coefficients (D), developed from the diffusion-controlled NMR Spectroscopy (DOSY) measurements, for the complexation of the selected imidazoline drugs with CB[7] and CB[8], were decreased in the presence of hosts compared to the free guests indicating the formation of the guest-host adduct. Furthermore, we conducted molecular dynamic simulations and quantum mechanics calculations on these complexes. The results of the theoretical study corroborate the experimental findings and have also shed light on the mechanism of inclusion of the guests into the two hosts. This study generates initial data for potential drug delivery or drug formulation systems for these three selected imidazoline drug compounds based on their inclusion into the CB[n] cavities.

Keywords: cucurbit[n]urils, imidazoline, inclusion complexes, molecular dynamics, DFT calculations, mass spectrometry

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Authors: Soufiene Ilahi

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We have used Photothermal deflection spectroscopy PTD to investigate the impact of doping on electronics properties of bulk. Then, the extraction of these parameters is performed by fitting the theoretical curves to the experimental PTD ones. We have remarked that electron mobility in p type C-doped GaAs is about 300 cm2/V·s. Accordinagly, the diffusion length of minority carrier lifetime is equal to 5 (± 7%), 5 (± 4,4%) and 1.42 µm (± 7,2 %) for the Cr, C and Si doped GaAs respectively. Surface recombination velocity varies randomly that can be found around of 7942 m/s, 100 m/s and 153 m/s GaAs doped Si, Cr, C, respectively.

Keywords: nonradiative lifetime, mobility of minority carrier, diffusion length, surface and interface recombination in GaAs

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Authors: Gülşah Çelik Gül, Figen Kurtuluş

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Cesium molybdates with general formula CsMIII(MoO4)2, where MIII = Bi, Dy, Pr, Er, exhibit rich polymorphism, and crystallize in a layered structure. These properties cause intensive studies on cesium molybdates. CsBi(MoO4)2 was synthesized by microwave method by using cerium sulphate, bismuth oxide and molybdenum (VI) oxide in an appropriate molar ratio. Characterizations were done by x-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy/energy dispersive analyze (SEM/EDS), thermo gravimetric/differantial thermal analysis (TG/DTA).

Keywords: cesium bismuth dimolybdate, microwave synthesis, powder x-ray diffraction, rare earth dimolybdates

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Authors: Fatima Zohra Belghait, Nawal Cheikh, Oscar Palacios, Ramon Barnadas, Pau Bayon

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Metalloporphyrin and its derivatives play an important role in different scientific areas due to its tetradentate vacant site in the center that is suitable for metal coordination. Metalosomes (MTS) are supramolecular aggregates (similar to liposomes) generated by the self-assembly of compounds similar to phospholipids (with a polar and a hydrophobic part), but incorporating, as part of their membrane, molecules that contain bound metals. The aim of our work is to synthesise metalosomes containing catioinc amphiphilic porphyrin and their complexes with Fe and Cu to study their therapeutical applications. All synthesized compounds were confirmed with Dynamic Light Scattering; elemental analysis, Ultraviolet–visible spectroscopy

Keywords: metalloporphyrin, amphiphilique porphyrin, metalosomes, supramolecular

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Authors: Vikas Kumar

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Portable batteries are reliable source of mobile energy to power smart wearable electronics, medical devices, communications, and others internet of thing (IoT) devices. There is a continuous increase in demand for thinner, more flexible battery with high energy density and reliability to meet the requirement. For a flexible battery, factors that affect these properties are the stability of current collectors, electrode materials and their interfaces with the corrosive electrolytes. State-of-the-art conventional and flexible batteries utilise carbon as an electrode and current collectors which cause high internal resistance (~100 ohms) and limit the peak current to ~1mA. This makes them unsuitable for a wide range of applications. Replacing the carbon parts with metallic components would reduce the internal resistance (and hence reduce parasitic loss), but significantly increases the risk of corrosion due to galvanic interactions within the battery. To overcome these challenges, low cost electroplated nickel (Ni) on copper (Cu) was studied as a potential anode current collector for a zinc-manganese oxide primary battery with different concentration of NH4Cl/ZnCl2 electrolyte. Using electrical impedance spectroscopy (EIS), we monitored the open circuit potential (OCP) of electroplated nickel (different thicknesses) in different concentration of electrolytes to optimise the thickness of Ni coating. Our results show that electroless Ni coating suffer excessive corrosion in these electrolytes. Corrosion rates of Ni coatings for different concentrations of electrolytes have been calculated with Tafel analysis. These results suggest that for electroplated Ni, channelling and/or open porosity is a major issue, which was confirmed by morphological analysis. These channels are an easy pathway for electrolyte to penetrate thorough Ni to corrode the Ni/Cu interface completely. We further investigated the incorporation of a special printed graphene layer on Ni to provide corrosion protection in this corrosive electrolyte medium. We find that the incorporation of printed graphene layer provides the corrosion protection to the Ni and enhances the chemical bonding between the active materials and current collector and also decreases the overall internal resistance of the battery system.

Keywords: corrosion, electrical impedance spectroscopy, flexible battery, graphene, metal current collector

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Authors: Massimo Morichi

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Over the last five years, starting in 2019, several nuclear measurement systems have been conceived and realized for specific nuclear safeguards applications, as well as for nuclear security, implementing some innovative technologies and methods for attended and unattended nuclear measurements. Some of those technologies imply the integration of combined gamma and neutron detection systems both for counting and spectroscopic applications that allow the SNM (Special Nuclear Material) verification and quantification through specific simultaneous measurements (gamma and neutron) from standard to high count rate due to high flux irradiation. IAEA has implemented some of these technologies in key international safeguards inspections worldwide, like a Fast Neutron Collar Monitor for fresh fuel verification of U235 mass (used during inspections for material declaration verification) or for unattended measuring systems with a distinct shift register installed in an anti-tampering sealed housing in unattended mode (remote inspection and continuous monitoring) together with an Unattended Multichannel Analyzer for spectroscopy analysis of SNM like canisters. Such developments, realized with integrated mid-resolution scintillators (FWHM: <3,5%) together with organic scintillators such as Stilbene detectors or Liquid sealed scintillators like EJ-309 with great pulse shape discrimination managed by a fast DAQ and with a high level of system integration, are offering in the near term the possibility to enhance further their implementation, reducing the form factor in order to facilitate their implementation in many critical parts of the Nuclear Fuel Operations as well as of the Next generation of Nuclear Reactors. This will facilitate embedding these advanced technical solutions in the next generation of nuclear installations, assuring the implementation of the Safeguards by Design requested by IAEA for all future/novel nuclear installations. This work presents the most recent designs/systems and provides some clear examples of ongoing applications on the Fuel Cycle-Fuel Fabrication as well as for the SMR/AMR and microreactors. Detailed technology testing and validation in different configuration if provided together with some case-studies and operational implications.

Keywords: nuclear safeguard, gamma and neutron detection systems, spectroscopy analysis, nuclear fuel cycle, nuclear power reactors, decommissioning dismantling, nuclear security

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Authors: Wanida Wonsawat

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Bioreduction of silver nanoparticles (AgNPs) from silver ions (Ag+) using water extract of Thai basil leaf was successfully carried out. The basil leaf extract provided a reducing agent and stabilizing agent for a synthesis of metal nanoparticles. Silver nanoparticles received from cut and uncut basil leaf was compared. The resulting silver nanoparticles are characterized by UV-Vis spectroscopy. The maximum intensities of silver nanoparticle from cut and uncut basil leaf were 410 and 420, respectively. The techniques involved are simple, eco-friendly and rapid.

Keywords: basil leaves, silver nanoparticles, green synthesis, plant extract

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Authors: V. Viliene, V. Sasyte, A. Raceviciute-Stupeliene, R. Gruzauskas

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In horse nutrition, the most suitable cereal for their rations composition could be defined as oats and barley. Oats have high nutritive value because it provides more protein, fiber, iron and zinc than other whole grains, has good taste, and an activity of stimulating metabolic changes in the body. Another cereal – barley is very similar to oats as a feed except for some characteristics that affect how it is used; however, barley is lower in fiber than oats and is classified as a "heavy" feed. The value of oats and barley grain, first of all is dependent on its composition. Near-infrared spectroscopy (NIRS) has long been considered and used as a significant method in component and quality analysis and as an emerging technology for authenticity applications for cereal quality control. This paper presents the chemical and amino acid composition of different varieties of barley and oats, also digestible energy of different cereals for horses. Ten different spring barley (n = 5) and oats (n = 5) varieties, grown in one location in Lithuania, were assayed for their chemical composition (dry matter, crude protein, crude fat, crude ash, crude fiber, starch) and amino acids content, digestible amino acids and amino acids digestibility. Also, the grains digestible energy for horses was calculated. The oats and barley samples reflectance spectra were measured by means of NIRS using Foss-Tecator DS2500 equipment. The chemical components: fat, crude protein, starch and fiber differed statistically (P<0.05) between the oats and barley varieties. The highest total amino acid content between oats was determined in variety Flamingsprofi (4.56 g/kg) and the lowest – variety Circle (3.57 g/kg), and between barley - respectively in varieties Publican (3.50 g/kg) and Sebastian (3.11 g/kg). The different varieties of oats digestible amino acid content varied from 3.11 g/kg to 4.07 g/kg; barley different varieties varied from 2.59 g/kg to 2.94 g/kg. The average amino acids digestibility of oats varied from 74.4% (Liz) to 95.6% (Fen) and in barley - from 75.8 % (Tre) to 89.6% (Fen). The amount of digestible energy in the analyzed varieties of oats and barley was an average compound 13.74 MJ/kg DM and 14.85 MJ/kg DM, respectively. An analysis of the results showed that different varieties of oats compared with barley are preferable for horse nutrition according to the crude fat, crude fiber, ash and separate amino acids content, but the analyzed barley varieties dominated the higher amounts of crude protein, the digestible Liz amount and higher DE content, and thus, could be recommended for making feed formulation for horses combining oats and barley, taking into account the chemical composition of using cereal varieties.

Keywords: barley, digestive energy, horses, nutritional value, oats

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Authors: Elham Moniri, Parvane Bozorgniya, Hamidreza Shahbazi

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In this research, poly urea-formaldehyde was prepared. The poly urea-formaldehyde was characterized by fourier transform infra-red spectroscopy. Then the effects of various parameters on Pb(II) sorption such as pH, contact time were studied. The optimum pH value for sorption of Pb(II) was 5. The sorption capacity of poly urea-formaldehyde for Pb(II) were 40 mg g−1. A Pb(II) removal of 90% was obtained. The profile of Pb(II) uptake on this sorbent reflects good accessibility of the chelating sites in the poly urea-formaldehyde. The developed method was utilized for determination of Pb(II) in environmental water samples by flame atomic absorption spectrometry with satisfactory results.

Keywords: poly urea-formaldehyde, lead Ion, environmental sample, determination

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Authors: P. Suchismita Behera, V. G. Sathe, A. K. Nigam, P. A. Bhobe

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Co-existence of long-range ferromagnetism and semi-conductivity with correlated behavior of structural, magnetic, optical and electrical properties in various sites doping at CdCr2Se4 makes it a most promising candidate for spin-based electronic applications and magnetic devices. It orders ferromagnetically below TC = 130 K with a direct band gap of ~ 1.5 eV. The magnetic ordering is believed to result from strong competition between the direct antiferromagnetic Cr-Cr spin couplings and the ferromagnetic Cr-Se-Cr exchange interactions. With an aim of understanding the influence of crystal structure on its magnetic properties without disturbing the magnetic site, we investigated four compositions with 3%, 5%, 7% and 10% of Sn-substitution at Cd-site. Partial substitution of Cd2+ (0.78Å) by small sized nonmagnetic ion, Sn4+ (0.55Å), is expected to bring about local lattice distortion as well as a change in electronic charge distribution. The structural disorder would affect the Cd/Sn – Se bonds thus affecting the Cr-Cr and Cr-Se-Cr bonds. Whereas, the charge imbalance created due to Sn4+ substitution at Cd2+ leads to the possibility of Cr mixed valence state. Our investigation of the local crystal structure using the EXAFS, Raman spectroscopy and magnetic properties using SQUID magnetometry of the Cd1-xSnxCr2Se4 series reflects this premise. All compositions maintain the Fd3m cubic symmetry with tetrahedral distribution of Sn at Cd-site, as confirmed by XRD analysis. Lattice parameters were determined from the Rietveld refinement technique of the XRD data and further confirmed from the EXAFS spectra recorded at Cr K-edge. Presence of five Raman-active phonon vibrational modes viz. (T2g (1), T2g (2), T2g (3), Eg, A1g) in the Raman spectra further confirms the crystal symmetry. Temperature dependence of the Raman data provides interesting insight to the spin– phonon coupling, known to dominate the magneto-capacitive properties in the parent compound. Below the magnetic ordering temperature, the longitudinal damping of Eg mode associated with Se-Cd/Sn-Se bending and T2g (2) mode associated to Cr-Se-Cr interaction, show interesting deviations with respect to increase in Sn substitution. Besides providing the estimate of TC, the magnetic measurements recorded as a function of field provide the values of total magnetic moment for all the studied compositions indicative of formation of multiple Cr valences.

Keywords: exchange interactions, EXAFS, ferromagnetism, Raman spectroscopy, spinel chalcogenides

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Authors: M. Vijaya Bhaskar Reddy

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The air-dried and powdered methanol solvent extraction of the rhizomes of Alpinia galangal is subjected to bio-assay guided fractionation and isolation yielded a known compound namely, 1'-S-1'-Acetoxychavicol acetate (1). The isolated known compound has been identified based on the physical, spectral data (IR, ¹H, ¹³C, NMR and mass spectroscopy) and comparison with an authentic sample. Finally isolated 1'-S-1'-Acetoxychavicol acetate (1) was confirmed by synthesis. The crude methanol extract and identified known compound (1) were tested for antidandruff property against Malassezia furfur showed with MIC 1000 µg/mL and 7.81 µg/mL, respectively.

Keywords: Alpinia galanga, isolation, 1'-S-1'-Acetoxychavicol acetate, antidandruff activity, Malassezia furfur

Procedia PDF Downloads 172

Authors: Pham-Thi Huong, Byeong-Kyu Lee, Chi-Hyeon Lee, JiTae Kim

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This study analyzed the removal of p-nitrophenol from wastewater using Fe-nano zeolite synthesized. The basic physical-chemical properties of Fe-nano zeolite was determined by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy. We focus on finding out the optimum conditions in adsorption and desorption processes for removal of p-nitrophenol by using Fe-nano zeolite in wastewater. The optimum pH for p-nitrophenol removal in wastewater was 5.0. Adsorption isotherms were better fitted with the Langmuir isotherm than with the Freundlich with 165.58 mg/g adsorption capacity of p-nitrophenol. These findings support potential of Fe-nano zeolite as an effective adsorbent for p-nitrophenol removal from wastewater.

Keywords: Fe-nano zeolite, adsorption, wastewater, regeneration

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Authors: V. Sai Geethika, Sai Snehitha Yadavalli, Swati Ghosh Acharyya

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This study involves a single element and simultaneous electrochemical detection of heavy metal ions through square wave anodic stripping voltammetry. A glassy carbon electrode was used to detect and quantify heavy metals such as As(III), Hg(II), Cr(VI) ions in water. Under optimized conditions, peak separation was obtained by varying concentrations, scan rates, and temperatures. As (III), Hg (II), Cr (III) were simultaneously detected with GCE. Several analytical methods, such as inductively coupled plasma mass spectroscopy (ICP-MS), atomic absorption spectroscopy (AAS), were used previously to detect heavy metal ions, which are authentic but are not good enough for online monitoring due to the bulkiness of the equipment. The study provides a good alternative that is simple, more efficient, and low-cost, involving a portable potentiostat. Heavy metals having different oxidation states can be detected by anodic stripping voltammetry. This method can be easily integrated with electronics. Square wave Anodic stripping voltammetry is used with a potential range of -2.5 V – 2.5 V for single ion detection by a three-electrode cell consisting of silver/silver chloride(Ag/AgCl) as reference and platinum (Pt) counter and glassy carbon (GCE) working electrodes. All three ions are optimized by varying the parameters like concentration, scan rate, pH, temperature, and all these optimized parameters were used for studying the effects of simultaneous detection. The procedure involves preparing an electrolyte using deionized water, cleaning the surface of GCE, depositing the ions by applying the redox potentials obtained from cyclic voltammetry (CV), and then detecting by applying oxidizing potential, i.e., stripping voltage. So this includes ASV techniques such as open-circuit voltage (OCV), chronoamperometry (CA), and square wave voltammetry (SWV). Firstly, the concentration of the ions varied from 50 ppb to 5000 ppb, and an optimum concentration was determined where the three ions were detected. A concentration of 400 ppb was used while varying the temperatures in the range of 25°C – 45°C. Optimum peak intensity was obtained at a temperature of 30°C with a low scan rate of 0.005 V-s⁻¹. All the parameters were optimized, and several effects have been noticed while three ions As(II), Cr(III), Hg(II) were detected alone and simultaneously.

Keywords: Arsenic(III), Chromium(III), glassy carbon electrode, Mercury (II), square wave anodic stripping voltammetry

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Authors: Mecabih Zohra

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Water is such an important element of many manufacturing processes which that use a big amount of chemical substances, It is likely to cause it contamination of water returning to rivers by industrial discharged. These contaminants can be a high in suspended solid and chemical oxygen demand. In this study, urban wastewater of sidi bel abbes city (Algeria) was treated by adsorption using modified bentonite from Magnia (Algeria) by conducting batch experiments to investigate its equilibrium characteristics and kinetics. Purified bentonite is characterized by; CEC, XRF, BET, FITR, XRD, SEM and 27Al spectroscopy. The results showed the removal of suspended solids exceeds 98.47% and COD up to 99.52%, and regarding of sorption efficiencies (qm), the maximum COD sorption efficiencies (qm) calculated using the Langmuir model is 156.23, 64.47 and 17.19 mg/g respectively, for a pH range of 4 to 9.

Keywords: adsorption, bentonite, COD, wastewater

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Authors: Aisha Ganash

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Poly(o-phenylendiamine) and poly(ophenylendiamine)/ZnO(PoPd/ZnO) nanocomposites coating were prepared on type-304 austenitic stainless steel (SS) using H2SO4 acid as electrolyte by potentiostatic methods. Fourier transforms infrared spectroscopy and scanning electron microscopy techniques were used to characterize the composition and structure of PoPd/ZnO nanocomposites. The corrosion protection of polymer coatings ability was studied by Eocp-time measurement, anodic and cathodic potentiodynamic polarization and Impedance techniques in 3.5% NaCl as a corrosive solution. It was found that ZnO nanoparticles improve the barrier and electrochemical anticorrosive properties of poly(o-phenylendiamine).

Keywords: anticorrosion, conducting polymers, electrochemistry, nanocomposites

Procedia PDF Downloads 293

Authors: Mecabih Zohra

Abstract:

Water is such an important element of many manufacturing processes which that use a big amount of chemical substances, It is likely to cause it contamination of water returning to rivers by industrial discharged. These contaminants can be a high in suspended solid and chemical oxygen demand. In this study, urban wastewater of sidi bel abbes city (Algeria) was treated by adsorption using modified bentonite from Magnia (Algeria) by conducting batch experiments to investigate its equilibrium characteristics and kinetics. Purified bentonite is characterized by; CEC, XRF, BET, FITR, XRD, SEM and 27Al spectroscopy. The results showed the removal of suspended solids exceeds 98.47% and COD up to 99.52%, and regarding of sorption efficiencies (qm), the maximum COD sorption efficiencies (qm) calculated using the Langmuir model is 156.23, 64.47 and 17.19 mg/g respectively, for a pH range of 4 to 9.

Keywords: adsorption, bentonite, COD, wastewater

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Authors: Mohamed Abdelmounim Bakkali, Mustapha El Mataouy, Abellatif Aaliti, Mouhamed Khaddor

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In the paper, we study the effects of introducing hafnium oxide on Raman spectra of silica glass planar waveguide activated by 0.3 mol% Er3+ ions. This work compares Raman spectra measured for three thin films deposited on silicon substrate. The films were prepared with different molar ratio of Si/Hf using sol-gel method and deposited by dip coating technique. The effect of hafnium oxide incorporation on the waveguides shows the evolution of the structure of this material. This structural information is useful to understand the luminescence intensity by means of ion–ion interaction mechanisms.

Keywords: optical amplifiers, non-bridging oxygen, erbium, sol-gel, waveguide, silica-hafnia

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Authors: Ahmed A. Farag, M. A. Hgazy

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The influence of three Schiff bases (SB-I, SB-II, and SB-III) on the corrosion of carbon steel in 0.5 M H2SO4 solution was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The inhibition efficiency increases with the concentration of the Schiff bases and follow the trend: SB-III > SB-II > SB-I. Tafel polarization measurements revealed that the three tested inhibitors function as anodic inhibitors. The thermodynamic parameters Kads and ΔGºads are calculated and discussed. The Langmuir isotherm equation was found to provide an accurate description of the adsorption behaviour of the investigated Schiff bases. Depending on the results, the inhibitive mechanism was proposed.

Keywords: Schiff bases, corrosion inhibitors, EIS, adsorption

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Authors: Maria V. Morozova, Yulia V. Emelyanova, Anastasia A. Levina, Elena S. Buyanova, Zoya A. Mikhaylovskaya, Sofia A. Petrova

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The solid solutions of lanthanum niobates substituted by yttrium, bismuth and tungsten were synthesized. The structure of the solid solutions is either LaNbO4-based monoclinic or BiNbO4-based triclinic. The series where niobium is substituted by tungsten on B site reveals phase-modulated structure. The values of cell parameters decrease with increasing the dopant concentration for all samples except the tungsten series although the latter show higher total conductivity.

Keywords: impedance spectroscopy, LaNbO4, lanthanum ortho-niobates, solid electrolyte

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Authors: Abbas Teimouri, Leila Ghorbanian, Iren Dabirian

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This work focused on preparation and characterizations of silk fibroin (SF)/nanodiopside nanoceramic via electrospinning process. Nanofibrous scaffolds were characterized by combined techniques of scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD). The results confirmed that fabricated SF/diopside scaffolds improved cell attachment and proliferation. The results indicated that the electrospun of SF/nanodiopside nanofibrous scaffolds could be considered as ideal candidates for tissue engineering.

Keywords: electrospinning, nanofibers, silk fibroin, diopside, composite scaffold

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Authors: Ruby Priya, Om Parkash Pandey

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Eu doped Gd₂O₃ phosphors are synthesized via co-precipitation method using ammonia as a precipitating agent. The concentration of the Eu was set as 4 mol% for all the samples. The effect of the surfactants (CTAB, PEG, and SDS) on the structural, morphological and luminescent properties has been studied in details. The as-synthesized phosphors were characterized by X-ray diffraction technique, Field emission scanning electron microscopy, Fourier transformed infrared spectroscopy and photoluminescence technique. It was observed that the surfactants have not changed the crystal structure, but influenced the morphology of as-synthesized phosphors to a great extent. The as-synthesized phosphors are expected to be promising candidates for optoelectronic devices, biosensors, MRI contrast agents and various biomedical applications.

Keywords: co-precipitation, Europium, photoluminescence, surfactants

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Authors: Paul R Armstrong

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Doubled haploids (DHs) have become an important breeding tool for creating maize inbred lines, although several bottlenecks in the DH production process limit wider development, application, and adoption of the technique. DH kernels are typically sorted manually and represent about 10% of the seeds in a much larger pool where the remaining 90% are hybrid siblings. This introduces time constraints on DH production and manual sorting is often not accurate. Automated sorting based on the chemical composition of the kernel can be effective, but devices, namely NMR, have not achieved the sorting speed to be a cost-effective replacement to manual sorting. This study evaluated a single kernel near-infrared reflectance spectroscopy (skNIR) platform to accurately identify DH kernels based on oil content. The skNIR platform is a higher-throughput device, approximately 3 seeds/s, that uses spectra to predict oil content of each kernel from maize crosses intentionally developed to create larger than normal oil differences, 1.5%-2%, between DH and hybrid kernels. Spectra from the skNIR were used to construct a partial least squares regression (PLS) model for oil and for a categorical reference model of 1 (DH kernel) or 2 (hybrid kernel) and then used to sort several crosses to evaluate performance. Two approaches were used for sorting. The first used a general PLS model developed from all crosses to predict oil content and then used for sorting each induction cross, the second was the development of a specific model from a single induction cross where approximately fifty DH and one hundred hybrid kernels used. This second approach used a categorical reference value of 1 and 2, instead of oil content, for the PLS model and kernels selected for the calibration set were manually referenced based on traditional commercial methods using coloration of the tip cap and germ areas. The generalized PLS oil model statistics were R2 = 0.94 and RMSE = .93% for kernels spanning an oil content of 2.7% to 19.3%. Sorting by this model resulted in extracting 55% to 85% of haploid kernels from the four induction crosses. Using the second method of generating a model for each cross yielded model statistics ranging from R2s = 0.96 to 0.98 and RMSEs from 0.08 to 0.10. Sorting in this case resulted in 100% correct classification but required models that were cross. In summary, the first generalized model oil method could be used to sort a significant number of kernels from a kernel pool but was not close to the accuracy of developing a sorting model from a single cross. The penalty for the second method is that a PLS model would need to be developed for each individual cross. In conclusion both methods could find useful application in the sorting of DH from hybrid kernels.

Keywords: NIR, haploids, maize, sorting

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Authors: E. Changizi, E. Ghasemi, B. Ramezanzadeh, M. Mahdavian

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In this study, the graphene oxide was functionalized with polyisocyanate (piGO). The functionalization was carried out at 45⁰C for 24 hrs under nitrogen atmosphere. The X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR) and thermal gravimetric analysis (TGA) were utilized in order to evaluate the GO functionalization. The GO and piGO stability were then investigated in polar and nonpolar solvents. Results obtained showed that polyisocyanate was successfully grafted on the surface of graphen oxide sheets through covalent bonds formation. The surface nature of the graphen oxide was changed into the hydrophobic after functionalization. Moreover, the graphen oxide sheets interlayer distance increased after modification.

Keywords: graphen oxide, functionalization, polyisocyanate, XRD, TGA, FTIR

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Authors: Homayon Ahmad Panahi, Amir Hesam Hassani, Akram Torki, Elham Moniri

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A new sorbent was synthesized through chemical modification of clinoptilolite zeolite using 2-naphtol, and characterized with fourier transform infrared spectroscopy and elemental analysis methods and applied for the removal and elimination of trace naphthalene from water samples. The optimum pH value for sorption of the naphthalene by modified zeolite was in acidic pH. The sorption capacity of modified zeolite was 142 mg. g−1. Isotherm models, Langmuir, Frendlich and Temkin were employed to analyze the adsorption capacity of modified zeolite, which revealed that naphthalene adsorption by this zeolite follows Langmuir model.

Keywords: zeolite, clinoptilolite, modification, naphthalene

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Authors: M. Dekmouche, M. Hadjada, Z. Rahmani, M. Saidi

Abstract:

The effect of iodide ions on the corrosion inhibition of mild steel in 20% sulfuric acid in the presence of 3-méthylthio-5-p-méthoxyphényl-1,2-dithiolylium against anion (I-) A1 synthesized in our laboratory,was studied by different electrochemical techniques such as electrochemical impedance spectroscopy, potentiodynamic polarization. The obtained results showed that A1 effectively reduces the corrosion rate of steel. The adsorption of 3-méthylthio-5-p-méthoxyphényl-1,2-dithiolylium against anion (I-) followed Langmuir and temkin adsorption isotherm.

Keywords: steel XC52, corrosion, inhibition, 3-méthylthio-5-p-méthoxyphényl-1, 2-dithiolylium against anion (I-) , sulfuric acid

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Authors: Maryam Sabbaghan, Pegah Sofalgar

Abstract:

Over the past few decades, a significant amount of research activities in the chemical community has been directed towards green synthesis. This area of chemistry has received extensive attention because of environmentally benign processes as well as economically viable. In this article, the MgO nanoparticles were prepared by different methods in the present of ionic liquids. A wide range of Magnesium oxide particle sizes within the nanometer scale is obtained by these methods. The structure of these MgO particles was studied by using X-ray diffraction (XRD), Infrared spectroscopy (IR), and scanning electron microscopy (SEM). It was found that the formation of nanoparticle could involve the role of performed 'nucleus' and used template to control the growth rate of nucleuses. The crystallite size of the MgO products was in a range from 31 to 77 nm.

Keywords: MgO, ionic liquid, nanoparticles, green chemistry

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Authors: Smita Jauhari, Bhupendra Mistry

Abstract:

Schiff base (E)-2-methyl-N-(tetrazolo[1,5-a]quinolin-4-ylmethylene)aniline (QMA) was synthesized, and its inhibitive effect for mild steel in 1M HCl solution was investigated by weight loss measurement and electrochemical tests.From the weight loss measurements and electrochemical tests, it was observed that the inhibition efficiency increases with the increase in the Schiff base concentration and reaches a maximum at the optimum concentration. This is further confirmed by the decrease in corrosion rate. It is found that the system follows Langmuir adsorption isotherm.

Keywords: Schiff base, acid corrosion, electrochemical impedance spectroscopy, polarization

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Authors: Rakesh Dogra, Arun Kumar, Arvind Kumar Sharma

Abstract:

This paper reports the thermoluminescence as well as optical properties of rare earth doped lithium fluoride (LiF) nanophosphor, synthesized via chemical route. The rare earth impurities (Yb and Sm) have been observed to increase the deep trap center capacity, which, in turn, enhance the radiation resistance of the LiF. This suggests the viability of these materials to be used as high dose thermoluminescent detectors at high temperature. Further, optical absorption measurements revealed the formation of radiation induced stable color centers in LiF at room temperature, which are independent of the rare earth dopant.

Keywords: lithium flouride, thermoluminescence, UV-VIS spectroscopy, Gamma radiations

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Authors: S. R. Kumar, Shashikant Rajpal

Abstract:

A nanocrystalline thin film of ZnSe was successfully electrodeposited on copper substrate using a non-aqueous solution and subsequently annealed in air at 400°C. XRD analysis indicates the polycrystalline deposit of (111) plane in both the cases. The sharpness of the peak increases due to annealing of the film and average grain size increases to 20 nm to 27nm. SEM photograph indicate that grains are uniform and densely distributed over the surface. Due to annealing the average grain size increased by 20%. The EDS spectroscopy shows the ratio of Zn & Se is 1.1 in case of annealed film. AFM analysis indicates the average roughness of the film reduces from 181nm to 165nm due to annealing of the film. The bandgap also decreases from 2.71eV to 2.62eV.

Keywords: electrodeposition, non-aqueous medium, SEM, XRD

Procedia PDF Downloads 487