Search results for: aluminium oxide nanoparticles
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2795

Search results for: aluminium oxide nanoparticles

1835 Comparison of Different in vitro Models of the Blood-Brain Barrier for Study of Toxic Effects of Engineered Nanoparticles

Authors: Samir Dekali, David Crouzier

Abstract:

Due to their new physico-chemical properties engineered nanoparticles (ENPs) are increasingly employed in numerous industrial sectors (such as electronics, textile, aerospace, cosmetics, pharmaceuticals, food industry, etc). These new physico-chemical properties can also represent a threat for the human health. Consumers can notably be exposed involuntarily by different routes such as inhalation, ingestion or through the skin. Several studies recently reported a possible biodistribution of these ENPs on the blood-brain barrier (BBB). Consequently, there is a great need for developing BBB in vitro models representative of the in vivo situation and capable of rapidly and accurately assessing ENPs toxic effects and their potential translocation through this barrier. In this study, several in vitro models established with micro-endothelial brain cell lines of different origins (bEnd.3 mouse cell line or a new human cell line) co-cultivated or not with astrocytic cells (C6 rat or C8-B4 mouse cell lines) on Transwells® were compared using different endpoints: trans-endothelial resistance, permeability of the Lucifer yellow and protein junction labeling. Impact of NIST diesel exhaust particles on BBB cell viability is also discussed.

Keywords: nanoparticles, blood-brain barrier, diesel exhaust particles, toxicology

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1834 Electrochemical Studies of Nickel Nanoparticles Decorated the Surface of Some Conducting Polymers for Glucose Oxidation in Biofuel Cells

Authors: Z. Khalifa, K. M. Hassan, M. Abdel Azzem

Abstract:

Potential strategies for deriving useful forms of renewable high density energy from abundant energy stored in carbohydrates is direct conversion of glucose (GLU) to electrical power. A three novel versatile modified electrodes, synthesized by electrochemical polymerization of organic monomers on glassy carbon electrodes (GC), have been developed for biofuel cells results in stable and long-term power production. Electrocatalytic oxidation of glucose in alkaline solution on conducting polymers electrodes modified by incorporation of Ni nanoparticles (NiNPs) onto poly(1,5-aminonaphthalene) (1,5-PDAN), poly(1,8-diaminonaphthalene) (1,8-PDAN) and poly(1-amino-2-methyl-9,10-anthraquinone) (PAMAQ) was investigated. The electrocatalytic oxidation of glucose at NiNPs-modified 1,5-PDAN/GC, 1,8-PDAN/GC and PAMAQ/GC electrodes has been studied using voltammetry technique. The PDAN electrodes show a slight activity in the potential of interest. The prepared NiNPs/PAMAQ/GC catalyst showed a very interesting catalytic activity that was nicely comparable to the NiNPs/1,5-PDAN/GC, NiNPs/1,8-PDAN/GC modified electrodes. In advance, both shows a significant more catalytic activity compared to the reported data for electrodes for glucose electrocatalytic oxidation.

Keywords: biofuel cells, glucose oxidation, electrocatalysis, nanoparticles and modified electrodes

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1833 Corrosion Analysis and Interfacial Characterization of Al – Steel Metal Inert Gas Weld - Braze Dissimilar Joints by Micro Area X-Ray Diffraction Technique

Authors: S. S. Sravanthi, Swati Ghosh Acharyya

Abstract:

Automotive light weighting is of major prominence in the current times due to its contribution in improved fuel economy and reduced environmental pollution. Various arc welding technologies are being employed in the production of automobile components with reduced weight. The present study is of practical importance since it involves preferential substitution of Zinc coated mild steel with a light weight alloy such as 6061 Aluminium by means of Gas Metal Arc Welding (GMAW) – Brazing technique at different processing parameters. However, the fabricated joints have shown the generation of Al – Fe layer at the interfacial regions which was confirmed by the Scanning Electron Microscope and Energy Dispersion Spectroscopy. These Al-Fe compounds not only affect the mechanical strength, but also predominantly deteriorate the corrosion resistance of the joints. Hence, it is essential to understand the phases formed in this layer and their crystal structure. Micro area X - ray diffraction technique has been exclusively used for this study. Moreover, the crevice corrosion analysis at the joint interfaces was done by exposing the joints to 5 wt.% FeCl3 solution at regular time intervals as per ASTM G 48-03. The joints have shown a decreased crevice corrosion resistance with increased heat intensity. Inner surfaces of welds have shown severe oxide cracking and a remarkable weight loss when exposed to concentrated FeCl3. The weight loss was enhanced with decreased filler wire feed rate and increased heat intensity. 

Keywords: automobiles, welding, corrosion, lap joints, Micro XRD

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1832 Study of the Formation Mechanism of Dipalmitoylphosphatidylcholine Liposomes and Calcium Ion Complexes

Authors: T. Mdzinarashvili, M. Khvedelidze, E. Shekiladze, S. Chinchaladze, M. Mdzinarashvili

Abstract:

The study of the possible interaction between calcium ions and lipids is of great importance for the studies of complexes of calcium drug-carrying nanoparticles. We prepared calcium-containing complex liposomes from Dipalmitoylphosphatidylcholine (DPPC) lipids and studied their thermodynamic properties. In calorimetric studies, we determined that the phase transition temperature of these complexes is close to 420 C. It was shown that both hydrophobic and hydrophilic connections take part in the formation of calcium nanoparticles. We were interested in hydrophilic bonds represented by hydrogen bonds. We have shown that these hydrogen bonds are formed between the phospholipid heads, and the main contributor is the oxygen atoms in the phosphoric acid residues. In addition, based on the amount of heat absorbed during the breaking of hydrogen bonds formed between calcium-containing nanoparticle complexes, it can be concluded that the hydrogen atoms in the head of DPPC lipids form hydrogen bonds between P=O and P-O groups of phosphate. The energy of heat absorption measured by the calorimeter is of the order obtained by breaking the hydrogen bonds we have specified. Thus, we conclude that our approach to the model of liposome formation from lipids is correct. As for calcium atoms - due to the fact that it is present in the form of positive ions in the liposome, they will connect only with negatively charged phosphorus ions.

Keywords: DPPC, liposomes, calcium, complex nanoparticles

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1831 An Alternative Nano Design Strategy by Neutralized AMPS and Soy Bean Lecithin to Form Nanoparticles

Authors: Esra Cansever Mutlu, Muge Sennaroglu Bostan, Fatemeh Bahadori, Ebru Toksoy Oner, Mehmet S. Eroglu

Abstract:

Paclitaxel is used in treatment of different cancer types mainly breast, ovarian, lung and Kaposi’s sarcoma. It is poorly soluble in water; therefore, currently used formulations tremendously show side-effects and high toxicity. Encapsulation of the drug in a nano drug carrier which causes both reducing side effects and increasing drug activity is a desired new approach for the nano-medicine to target the site of cancer. In this study, synthesis of a novel nano paclitaxel formulation made of a new amphiphilic monomer was followed by the investigation of its pharmacological properties. UV radical polymerization was carried out by using the monomer Lecithin-2-Acrylamido-2-methylpropane (L-AMPS) and the drug-spacer, to obtain sterically high stabilized, biocompatible and biodegradable phospholipid nanoparticles, in which the drug paclitaxel (Pxl) was encapsulated (NanoPxl). Particles showed high drug loading capacity (68%) and also hydrodynamic size less than 200 nm with slight negative surface charge. The drug release profile was obtained and in vitro cytotoxicity test was performed on MCF-7 cell line. Consequently, these data indicated that paclitaxel loaded Lecithin-AMPS/PCL-MAC nanoparticles can be considered as a new, safe and effective nanocarrier for the treatment of breast cancer.

Keywords: paclitaxel, nanoparticle, drug delivery, L-AMPS

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1830 WO₃-SnO₂ Sensors for Selective Detection of Volatile Organic Compounds for Breath Analysis

Authors: Arpan Kumar Nayak, Debabrata Pradhan

Abstract:

A simple, single-step and one-pot hydrothermal method was employed to synthesize WO₃-SnO₂ mixed nanostructured metal oxides at 200°C in 12h. The SnO₂ nanoparticles were found to be uniformly decorated on the WO₃ nanoplates. Though it is widely known that noble metals such as Pt, Pd doping or decoration on metal oxides improve the sensing response and sensitivity, we varied the SnO₂ concentration in the WO₃-SnO₂ mixed oxide and demonstrated their performance in ammonia, ethanol and acetone sensing. The sensing performance of WO₃-(x)SnO₂ [x = 0.27, 0.54, 1.08] mixed nanostructured oxides was found to be not only superior to that of pristine oxides but also higher/better than that of reported noble metal-based sensors. The sensing properties (selectivity, limit of detection, response and recovery times) are measured as a function of operating temperature (150-350°C). In particular, the gas selectivity is found to be highly temperature-dependent with optimum performance obtained at 200°C, 300°C and 350°C for ammonia, ethanol, and acetone, respectively. The present results on cost effective WO₃-SnO₂ sensors can find potential application in human breath analysis by noninvasive detection.

Keywords: gas sensing, mixed oxides, nanoplates, ammonia, ethanol, acetone

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1829 Surface Enhanced Raman Substrate Detection on the Structure of γ-Aminobutyric Acid(GABA) Connected with Modified Gold-Chitosan Nanoparticles by Mercaptopropionic Acid (MPA)

Authors: Bingjie Wang, Su-Yeon Kwon, Ik-Joong Kang

Abstract:

A Surface-enhanced Raman Scattering (SERS) as the principle for enhancing Raman scattering by molecules adsorbed on rough metal surfaces or by nanostructures is used to detect the concentration change of γ-Aminobutyric Acid (GABA). As for the gold-chitosan nanoshell, it is made by using chitosan nanoparticles crosslinking with sodium tripolyphosphate(TPP) for the first step to form the chitosan nanoparticles, which would be covered with the gold sequentially. The size of the fabricated product was around 100nm. Based on the method that the sulfur end of the MPA linked to gold can form the very strong S–Au bond, and the carboxyl group, the other end of the MPA, can easily absorb the GABA. GABA is the mainly inhibitory neurotransmitter in the mammalian central nervous system in the human body. It plays such significant role in reducing neuronal excitability throughout the nervous system. When the system formed, it generated SERS, which made a clear difference in the intensity of Raman scattering within the range of GABA concentration. So it is obtained from the experiment that the calibration curve according to the GABA concentration relevant with the SERS scattering. In this study, DLS, SEM, FT-IR, UV, SERS were used to analyze the products to obtain the conclusion.

Keywords: chitosan-gold nanoshell, mercaptopropionic acid, γ-aminobutyric acid, surface-enhanced Raman scattering

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1828 Effect of Forging Pressure on Mechanical Properties and Microstructure of Similar and Dissimilar Friction Welded Joints (Aluminium, Copper, Steel)

Authors: Sagar Pandit

Abstract:

The present work focuses on the effect of various process parameters on the mechanical properties and microstructure of joints produced by continuous drive friction welding and linear friction welding. An attempt is made to investigate the feasibility of obtaining an acceptable weld joint between similar as well as dissimilar components and the microstructural changes have also been assessed once the good weld joints were considered (using Optical Microscopy and Scanning Electron Microscopy techniques). The impact of forging pressure in the microstructure of the weld joint has been studied and the variation in joint strength with varying forge pressure is analyzed. The weld joints were obtained two pair of dissimilar materials and one pair of similar materials, which are listed respectively as: Al-AA5083 & Cu-C101 (dissimilar), Aluminium alloy-3000 series & Mild Steel (dissimilar) and High Nitrogen Austenitic Stainless Steel pair (similar). Intermetallic phase formation was observed at the weld joints in the Al-Cu joint, which consequently harmed the properties of the joint (less tensile strength). It was also concluded that the increase in forging pressure led to both increment and decrement in the tensile strength of the joint depending on the similarity or dissimilarity of the components. The hardness was also observed to possess maximum as well as minimum values at the weld joint depending on the similarity or dissimilarity of workpieces. It was also suggested that a higher forging pressure is needed to obtain complete joining for the formation of the weld joint.

Keywords: forging pressure, friction welding, mechanical properties, microstructure

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1827 An Anode Based on Modified Silicon Nanostructured for Lithium – Ion Battery Application

Authors: C. Yaddaden, M. Berouaken, L. Talbi, K. Ayouz, M. Ayat, A. Cheriet, F. Boudeffar, A. Manseri, N. Gabouze

Abstract:

Lithium-ion batteries (LIBs) are widely used in various electronic devices due to their high energy density. However, the performance of the anode material in LIBs is crucial for enhancing the battery's overall efficiency. This research focuses on developing a new anode material by modifying silicon nanostructures, specifically porous silicon nanowires (PSiNWs) and porous silicon nanoparticles (NPSiP), with silver nanoparticles (Ag) to improve the performance of LIBs. The aim of this research is to investigate the potential application of PSiNWs/Ag and NPSiP/Ag as anodes in LIBs and evaluate their performance in terms of specific capacity and Coulombic efficiency. The research methodology involves the preparation of PSiNWs and NPSiP using metal-assisted chemical etching and electrochemical etching techniques, respectively. The Ag nanoparticles are introduced onto the nanostructures through electrodissolution of the porous film and ultrasonic treatment. Galvanostatic charge/discharge measurements are conducted between 1 and 0.01 V to evaluate the specific capacity and Coulombic efficiency of both PSiNWs/Ag and NPSiP/Ag electrodes. The specific capacity of the PSiNWs/Ag electrode is approximately 1800 mA h g-1, with a Coulombic efficiency of 98.8% at the first charge/discharge cycle. On the other hand, the NPSiP/Ag electrode exhibits a specific capacity of 2600 mAh g-1. Both electrodes show a slight increase in capacity retention after 80 cycles, attributed to the high porosity and surface area of the nanostructures and the stabilization of the solid electrolyte interphase (SEI). This research highlights the potential of using modified silicon nanostructures as anodes for LIBs, which can pave the way for the development of more efficient lithium-ion batteries.

Keywords: porous silicon nanowires, silicon nanoparticles, lithium-ion batteries, galvanostatic charge/discharge

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1826 Evaluation of Nanoparticle Application to Control Formation Damage in Porous Media: Laboratory and Mathematical Modelling

Authors: Gabriel Malgaresi, Sara Borazjani, Hadi Madani, Pavel Bedrikovetsky

Abstract:

Suspension-Colloidal flow in porous media occurs in numerous engineering fields, such as industrial water treatment, the disposal of industrial wastes into aquifers with the propagation of contaminants and low salinity water injection into petroleum reservoirs. The main effects are particle mobilization and captured by the porous rock, which can cause pore plugging and permeability reduction which is known as formation damage. Various factors such as fluid salinity, pH, temperature, and rock properties affect particle detachment. Formation damage is unfavorable specifically near injection and production wells. One way to control formation damage is pre-treatment of the rock with nanoparticles. Adsorption of nanoparticles on fines and rock surfaces alters zeta-potential of the surfaces and enhances the attachment force between the rock and fine particles. The main objective of this study is to develop a two-stage mathematical model for (1) flow and adsorption of nanoparticles on the rock in the pre-treatment stage and (2) fines migration and permeability reduction during the water production after the pre-treatment. The model accounts for adsorption and desorption of nanoparticles, fines migration, and kinetics of particle capture. The system of equations allows for the exact solution. The non-self-similar wave-interaction problem was solved by the Method of Characteristics. The analytical model is new in two ways: First, it accounts for the specific boundary and initial condition describing the injection of nanoparticle and production from the pre-treated porous media; second, it contains the effect of nanoparticle sorption hysteresis. The derived analytical model contains explicit formulae for the concentration fronts along with pressure drop. The solution is used to determine the optimal injection concentration of nanoparticle to avoid formation damage. The mathematical model was validated via an innovative laboratory program. The laboratory study includes two sets of core-flood experiments: (1) production of water without nanoparticle pre-treatment; (2) pre-treatment of a similar core with nanoparticles followed by water production. Positively-charged Alumina nanoparticles with the average particle size of 100 nm were used for the rock pre-treatment. The core was saturated with the nanoparticles and then flushed with low salinity water; pressure drop across the core and the outlet fine concentration was monitored and used for model validation. The results of the analytical modeling showed a significant reduction in the fine outlet concentration and formation damage. This observation was in great agreement with the results of core-flood data. The exact solution accurately describes fines particle breakthroughs and evaluates the positive effect of nanoparticles in formation damage. We show that the adsorbed concentration of nanoparticle highly affects the permeability of the porous media. For the laboratory case presented, the reduction of permeability after 1 PVI production in the pre-treated scenario is 50% lower than the reference case. The main outcome of this study is to provide a validated mathematical model to evaluate the effect of nanoparticles on formation damage.

Keywords: nano-particles, formation damage, permeability, fines migration

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1825 Silymarin Loaded Mesoporous Silica Nanoparticles: Preparation, Optimization, Pharmacodynamic and Oral Multi-Dose Safety Assessment

Authors: Sarah Nasr, Maha M. A. Nasra, Ossama Y. Abdallah

Abstract:

The present work aimed to prepare Silymarin loaded MCM-41 type mesoporous silica nanoparticles (MSNs) and to assess the system’s solubility enhancement ability on the pharmacodynamic performance of Silymarin as a hepatoprotective agent. MSNs prepared by soft-templating technique, were loaded with Silymarin, characterized for particle size, zeta potential, surface properties, DSC and XRPD. DSC and specific surface area data confirmed deposition of Silymarin in an amorphous state in MSNs’ pores. In-vitro drug dissolution testing displayed enhanced dissolution rate of Silymarin upon loading on MSNs. High dose Acetaminophen was then used to inflict hepatic injury upon albino male Wistar rats simultaneously receiving either free Silymarin, Silymarin loaded MSNs or blank MSNs. Plasma AST, ALT, albumin and total protein and liver homogenate content of TBARs or LDH as measures of antioxidant drug action were assessed for all animal groups. Results showed a significant superiority of Silymarin loaded MSNs to free drug in almost all parameters. Meanwhile prolonged administration of blank MSNs had no evident toxicity on rats.

Keywords: mesoporous silica nanoparticles, safety, solubility enhancement, silymarin

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1824 Preparation and Conductivity Measurements of LSM/YSZ Composite Solid Oxide Electrolysis Cell Anode Materials

Authors: Christian C. Vaso, Rinlee Butch M. Cervera

Abstract:

One of the most promising anode materials for solid oxide electrolysis cell (SOEC) application is the Sr-doped LaMnO3 (LSM) which is known to have a high electronic conductivity but low ionic conductivity. To increase the ionic conductivity or diffusion of ions through the anode, Yttria-stabilized Zirconia (YSZ), which has good ionic conductivity, is proposed to be combined with LSM to create a composite electrode and to obtain a high mixed ionic and electronic conducting anode. In this study, composite of lanthanum strontium manganite and YSZ oxide, La0.8Sr0.2MnO3/Zr0.92Y0.08O2 (LSM/YSZ), with different wt.% compositions of LSM and YSZ were synthesized using solid-state reaction. The obtained prepared composite samples of 60, 50, and 40 wt.% LSM with remaining wt.% of 40, 50, and 60, respectively for YSZ were fully characterized for its microstructure by using powder X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Fourier transform infrared (FTIR), and Scanning electron microscope/Energy dispersive spectroscopy (SEM/EDS) analyses. Surface morphology of the samples via SEM analysis revealed a well-sintered and densified pure LSM, while a more porous composite sample of LSM/YSZ was obtained. Electrochemical impedance measurements at intermediate temperature range (500-700 °C) of the synthesized samples were also performed which revealed that the 50 wt.% LSM with 50 wt.% YSZ (L50Y50) sample showed the highest total conductivity of 8.27x10-1 S/cm at 600 oC with 0.22 eV activation energy.

Keywords: ceramics, microstructure, fuel cells, electrochemical impedance spectroscopy

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1823 Influence of HbA1c on Nitric Oxide Level in Patients with Type 2 Diabetes Mellitus

Authors: Dara Kutsyk, Olga Bondarenko, Mariya Sorochka

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In 21-century type 2 diabetes (T2D) has become a global health and social problem in the whole world. The goal of treatment for patients with T2D is to prevent complications of diabetes - macrovascular diseases (heart disease, stroke, and peripheral vascular disease) and microvascular diseases (retinopathy, neuropathy and nephropathy). Nitric oxide (NO) plays an important role in maintaining vascular homeostasis. Loss of NO function is one of the earliest indicators of disease and its progression especially in patients with T2D. Aim: To compare NO level between patients with well and bad controlled glycemia in T2D. Methods: The study included 32 patients with T2D. The diagnosis of T2D was confirmed due to International Diabetes Federation (IDF) criteria 2015. Patients were divided into two groups: with well controlled glycaemia (HbA1c < 7%) and bad controlled glycaemia (HbA1c > 7%). The control group consists of 15 healthy subjects. Results: NO level in patients with T2D is significantly higher (27,2 ±3,1 µmol), compared to controls (18,86±0,9 µmol; p < 0,001). A significant difference in NO level was found between patients with bad controlled glycaemia (25,9±2,2 µmol) and well controlled glycaemia (28,7 ± 3,0 µmol; p<0,01). The study showed a moderate negative correlation between NO level and HbA1c (-0,399; р< 0,05). Conclusions: Production of NO is impaired in patients with T2D, especially with badly controlled glycaemia. With the increase in HbAc serum NO decreases. This can be the main target for prevention vascular complication in T2D.

Keywords: type 2 diabetes, glycated hemoglobin, nitric oxide, Diabetes mellitus

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1822 Effect of Substrate Temperature on Some Physical Properties of Doubly doped Tin Oxide Thin Films

Authors: Ahmet Battal, Demet Tatar, Bahattin Düzgün

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Various transparent conducting oxides (TCOs) are mostly used much applications due to many properties such as cheap, high transmittance/electrical conductivity etc. One of the clearest among TCOs, indium tin oxide (ITO), is the most widely used in many areas. However, as ITO is expensive and very low regarding reserve, other materials with suitable properties (especially SnO2 thin films) are be using instead of it. In this report, tin oxide thin films doubly doped with antimony and fluorine (AFTO) were deposited by spray at different substrate temperatures on glass substrate. It was investigated their structural, optical, electrical and luminescence properties. The substrate temperature was varied from 320 to 480 ˚C at the interval of 40 (±5) ºC. X-ray results were shown that the films are polycrystalline with tetragonal structure and oriented preferentially along (101), (200) and (210) directions. It was observed that the preferential orientations of crystal growth are not dependent on substrate temperature, but the intensity of preferential orientation was increased with increasing substrate temperature until 400 ºC. After this substrate temperature, they decreased. So, substrate temperature impact structure of these thin films. It was known from SEM analysis, the thin films have rough and homogenous and the surface of the films was affected by the substrate temperature i.e. grain size are increasing with increasing substrate temperature until 400 ºC. Also, SEM and AFM studies revealed the surface of AFTO thin films to be made of nanocrystalline particles. The average transmittance of the films in the visible range is 70-85%. Eg values of the films were investigated using the absorption spectra and found to be in the range 3,20-3,93 eV. The electrical resistivity decreases with increasing substrate temperature, then the electrical resistivity increases. PL spectra were found as a function of substrate temperature. With increasing substrate temperature, emission spectra shift a little bit to a UV region. Finally, tin oxide thin films were successfully prepared by this method and a spectroscopic characterization of the obtained films was performed. It was found that the films have very good physical properties. It was concluded that substrate temperature impacts thin film structure.

Keywords: thin films, spray pyrolysis, SnO2, doubly doped

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1821 Effect of Different Parameters in the Preparation of Antidiabetic Microparticules by Coacervation

Authors: Nawel Ouennoughi, Kamel Daoud

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During recent years, new pharmaceutical dosage forms were developed in the research laboratories and which consists of encapsulating one or more active molecules in a polymeric envelope. Several techniques of encapsulation allow obtaining the microparticles or the nanoparticles containing one or several polymers. In the industry, microencapsulation is implemented to fill the following objectives: to ensure protection, the compatibility and the stabilization of an active matter in a formulation, to carry out an adapted working, to improve the presentation of a product, to mask a taste or an odor, to modify and control the profile of release of an active matter to obtain, for example, prolonged or started effect. To this end, we focus ourselves on the encapsulation of the antidiabetic. It is an oral hypoglycemic agent belonging to the second generation of sulfonylurea’s commonly employed in the treatment of type II non-insulin-dependent diabetes in order to improve profile them dissolution. Our choice was made on the technique of encapsulation by complex coacervation with two types of polymers (gelatin and the gum Arabic) which is a physicochemical process. Several parameters were studied at the time of the formulation of the microparticles and the nanoparticles: temperature, pH, ratio of polymers etc. The microparticles and the nanoparticles obtained were characterized by microscopy, laser granulometry, FTIR and UV-visible spectrophotometry. The profile of dissolution obtained for the microparticles showed an improvement of the kinetics of dissolution compared to that obtained for the active ingredient.

Keywords: coacervation, gum Arabic, microencapsulation, gelatin

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1820 LAMOS - Layered Amorphous Metal Oxide Gas Sensors: New Interfaces for Gas Sensing Applications

Authors: Valentina Paolucci, Jessica De Santis, Vittorio Ricci, Giacomo Giorgi, Carlo Cantalini

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Despite their potential in gas sensing applications, the major drawback of 2D exfoliated metal dichalcogenides (MDs) is that they suffer from spontaneous oxidation in air, showing poor chemical stability under dry/wet conditions even at room temperature, limiting their practical exploitation. The aim of this work is to validate a synthesis strategy allowing microstructural and electrical stabilization of the oxides that inevitably form on the surface of 2D dichalcogenides. Taking advantage of spontaneous oxidation of MDs in air, we report on liquid phase exfoliated 2D-SnSe2 flakes annealed in static air at a temperature below the crystallization temperature of the native a-SnO2 oxide. This process yields a new class of 2D Layered Amorphous Metal Oxides Sensors (LAMOS), specifically few-layered amorphous a-SnO2, showing excellent gas sensing properties. Sensing tests were carried out at low operating temperature (i.e. 100°C) by exposing a-SnO2 to both oxidizing and reducing gases (i.e. NO2, H2S and H2) and different relative humidities ranging from 40% to 80% RH. The formation of stable nanosheets of amorphous a-SnO2 guarantees excellent reproducibility and stability of the response over one year. These results pave the way to new interesting research perspectives out considering the opportunity to synthesize homogeneous amorphous textures with no grain boundaries, no grains, no crystalline planes with different orientations, etc., following gas sensing mechanisms that likely differ from that of traditional crystalline metal oxide sensors. Moreover, the controlled annealing process could likely be extended to a large variety of Transition Metal Dichalcogenides (TMDs) and Metal Chalcogenides (MCs), where sulfur, selenium, or tellurium atoms can be easily displaced by O2 atoms (ΔG < 0), enabling the synthesis of a new family of amorphous interfaces.

Keywords: layered 2D materials, exfoliation, lamos, amorphous metal oxide sensors

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1819 Rare-Earth Ions Doped Zirconium Oxide Layers for Optical and Photovoltaic Applications

Authors: Sylwia Gieraltowska, Lukasz Wachnicki, Bartlomiej S. Witkowski, Marek Godlewski

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Oxide layers doped with rare-earth (RE) ions in optimized way can absorb short (ultraviolet light), which will be converted to visible light by so-called down-conversion. Down-conversion mechanisms are usually exploited to modify the incident solar spectrum. In down conversion, multiple low-energy photons are generated to exploit the energy of one incident high-energy photon. These RE-doped oxide materials have attracted a great deal of attention from researchers because of their potential for optical manipulation in optical devices (detectors, temperature sensors, and compact solid-state lasers, light-emitting diodes), bio-analysis, medical therapy, display technologies, and light harvesting (such as in photovoltaic cells). The zirconium dioxide (ZrO2) doped RE ions (Eu, Tb, Ce) multilayer structures were tested as active layers, which can convert short wave emission to light in the visible range (the down-conversion mechanism). For these applications original approach of deposition ZrO2 layers using the Atomic Layer Deposition (ALD) method and doping these layers with RE ions using the spin-coating technique was used. ALD films are deposited at relatively low temperature (well below 250°C). This can be an effective method to achieve the white-light emission and to improve on this way light conversion efficiency, by an extension of absorbed spectral range by a solar cell material. Photoluminescence (PL), X-ray diffraction (XRD), scanning electron microscope (SEM) and atomic force microscope (AFM) measurement are analyzed. The research was financially supported by the National Science Centre (decision No. DEC-2012/06/A/ST7/00398 and DEC- 2013/09/N/ST5/00901).

Keywords: ALD, oxide layers, photovoltaics, thin films

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1818 Developing Biocompatible Iridium Oxide Electrodes for Bone-Guided Extra-Cochlear Implant

Authors: Yung-Shan Lu, Chia-Fone Lee, Shang-Hsuan Li, Chien-Hao Liu

Abstract:

Recently, various bioelectronic devices have been developed for neurologic disease treatments via electro-stimulations such as cochlear implants and retinal prosthesis. Since the electric signal needs electrodes to be transmitted to an organism, electrodes play an important role of stimulations. The materials of stimulation electrodes affect the efficiency of the delivered currents. The higher the efficiency of the electrodes, the lower the threshold current can be used to stimulate the organism which minimizes the potential damages to the adjacent tissues. In this study, we proposed a biocompatible composite electrode composed of high-charge-capacity iridium oxide (IrOₓ) film for a bone-guide extra-cochlear implant. IrOₓ was exploited to decrease the threshold current due to its high capacitance and low impedance. The IrOₓ electrode was fabricated via microelectromechanical systems (MEMS) photolithography and examined with in-vivo tests with guinea pigs. Based on the measured responses of brain waves to sound, the results demonstrated that IrOₓ electrodes have a lower threshold current compared with the Platinum (Pt) electrodes. The research results are expected to be beneficial for implantable and biocompatible electrodes for electrical stimulations.

Keywords: cochlear implants, electrode, electrical stimulation, iridium oxide

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1817 Effect of Transition Metal (Fe, Mn) Ion Doping on TiO2 Nano Particles

Authors: Kirit Siddhapara, Dimple Shah

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In this research, we have studied the doping behaviors of two transition metal ion dopants on the crystal phase, particle sizes, XRD patterns, EDAX spectra, and photoreactivity of TiO2 nanoparticles. The crystalline size of TiO2 is close to 4 nm Calculated from (1 0 1) peak by using FWHM method in Scherrer’s equation. Test metal ion concentrations ranged from 1% to 4 at.%, we report the growth of [Fe, Mn]xTiO2 nanocrystals prepared by Sol-Gel technique, followed by freeze-drying treatment at -30°C temperature for 12hrs. The obtained Gel was thermally treated at different temperature like 200°C, 400°C, 600°C, 800°C. Thermal gravimetric analysis (TGA) shows that dopant concentration affects thermal decomposition. The photoreactivities of transition metal ion-doped TiO2 nanoparticles under UV irradiation were quantified by the degradation of formaldehyde.

Keywords: growth from solution, sol-gel method, nanomaterials, oxides, magnetic materials, titanium compounds

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1816 Development of Sulfite Biosensor Based on Sulfite Oxidase Immobilized on 3-Aminoproplytriethoxysilane Modified Indium Tin Oxide Electrode

Authors: Pawasuth Saengdee, Chamras Promptmas, Ting Zeng, Silke Leimkühler, Ulla Wollenberger

Abstract:

Sulfite has been used as a versatile preservative to limit the microbial growth and to control the taste in some food and beverage. However, it has been reported to cause a wide spectrum of severe adverse reactions. Therefore, it is important to determine the amount of sulfite in food and beverage to ensure consumer safety. An efficient electrocatalytic biosensor for sulfite detection was developed by immobilizing of human sulfite oxidase (hSO) on 3-aminoproplytriethoxysilane (APTES) modified indium tin oxide (ITO) electrode. Cyclic voltammetry was employed to investigate the electrochemical characteristics of the hSO modified ITO electrode for various pretreatment and binding conditions. Amperometry was also utilized to demonstrate the current responses of the sulfite sensor toward sodium sulfite in an aqueous solution at a potential of 0 V (vs. Ag/AgCl 1 M KCl). The proposed sulfite sensor has a linear range between 0.5 to 2 mM with a correlation coefficient 0.972. Then, the additional polymer layer of PVA was introduced to extend the linear range of sulfite sensor and protect the enzyme. The linear range of sulfite sensor with 5% coverage increases from 2.8 to 20 mM at a correlation coefficient of 0.983. In addition, the stability of sulfite sensor with 5% PVA coverage increases until 14 days when kept in 0.5 mM Tris-buffer, pH 7.0 at 4 8C. Therefore, this sensor could be applied for the detection of sulfite in the real sample, especially in food and beverage.

Keywords: sulfite oxidase, bioelectrocatalytsis, indium tin oxide, direct electrochemistry, sulfite sensor

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1815 Experimental Investigation with Different Inclination Angles on Copper Oscillating Heat Pipes Performance Using Fe2O3 / Kerosene under Magnetic Field

Authors: H. R. Goshayeshi, M. Mansori, M. Ahmady, M. Zhaloyi

Abstract:

This paper presents the result of an experimental investigation regarding the use of Fe2O3 nanoparticles added to Kerosene as a working fluid, under magnetic field for Copper Oscillating Heat pipe with inclination angle of 0°(horizontal), 15°, 30°, 45°, 60°, 75°, and 90° (vertical). The following were examined; measure the temperature distribution and heat transfer rate on Oscillating Heat Pipe (OHP), with magnetic field under different angles. Results showed that the addition of Fe2O3 nanoparticles under magnetic field improved thermal performance of OHP especially in 75°.

Keywords: copper oscillating heat pipe, Fe2O3, magnetic field, inclination angles

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1814 Synthesis, Characterization and Gas Sensing Applications of Perovskite CaZrO3 Nanoparticles

Authors: B. M. Patil

Abstract:

Calcium Zirconate (CaZrO3) has high protonic conductivities at elevated temperature in water or hydrogen atmosphere. Undoped calcium zirconate acts as a p-type semiconductor in air. In this paper, we reported synthesis of CaZrO3 nanoparticles via modified molecular precursor method. The precursor calcium zirconium oxalate (CZO) was synthesized by exchange reaction between freshly generated aqueous solution of sodium zirconyl oxalate and calcium acetate at room temperature. The controlled pyrolysis of CZO in air at 700°C for one hour resulted in the formation nanocrystalline CaZrO3 powder. CaZrO3 obtained by the present method was characterized by Simultaneous thermogravimetry and differential thermogravimetry (TG-DTA), X-ray diffraction (XRD), infra-red spectroscopy and transmission electron microscopy (TEM). The pellets of synthesized CaZrO3 fabricated, sintered at 1000°C for 5 hr and tested as sensors for NO2 and NH3 gases.

Keywords: CaZrO3, CZO, NO2, NH3

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1813 A Hybrid Film: NiFe₂O₄ Nanoparticles in Poly-3-Hydroxybutyrate as an Antibacterial Agent

Authors: Karen L. Rincon-Granados, América R. Vázquez-Olmos, Adriana-Patricia Rodríguez-Hernández, Gina Prado-Prone, Margarita Rivera, Roberto Y. Sato-Berrú

Abstract:

In this work, a hybrid film based on poly-3-hydroxybutyrate (P3HB) and nickel ferrite (NiFe₂O₄) nanoparticles (NPs) was obtained by a simple and reproducible methodology in order to study its antibacterial and cytotoxic properties. The motivation for this research is the current antimicrobial resistance (RAM). This is a threat to human health and development worldwide. RAM is caused by the emergence of bacterial strains resistant to traditional antibiotics that were used as treatment. Due to this, the need to investigate new alternatives for preventing and treating bacterial infections emerges. In this sense, metal oxide NPs have aroused great interest due to their unique physicochemical properties. However, their use is limited by the nanostructured nature, commonly obtained by chemical and physical synthesis methods, as powders or colloidal dispersions. Therefore, the incorporation of nanostructured materials in polymer matrices to obtain hybrid materials that allow disinfecting and preventing the spread of bacteria on various surfaces. Accordingly, this work presents the synthesis and study of the antibacterial properties of the P3HB@NiFe₂O₄ hybrid film as a potential material to inhibit bacterial growth. The NiFe₂O₄ NPs were previously synthesized by a mechanochemical method. The P3HB and P3HB@NiFe₂O₄ films were obtained by the solvent casting method. The films were characterized by X-ray diffraction (XRD), Raman scattering, and scanning electron microscopy (SEM). The XRD pattern showed that the NiFe₂O₄ NPs were incorporated into the P3HB polymer matrix and retained their nanometric sizes. By energy dispersive X-ray spectroscopy (EDS), it was observed that the NPs are homogeneously distributed in the film. The bactericidal effect of the films obtained was evaluated in vitro using the broth surface method against two opportunistic and nosocomial pathogens, Staphylococcus aureus and Pseudomonas aeruginosa. The bacterial growth results showed that the P3HB@NiFe₂O₄ hybrid film was inhibited by 97% and 96% for S. aureus and P. aeruginosa, respectively. Surprisingly, the P3HB film inhibited both bacterial strains by around 90%. The cytotoxicity of the NiFe₂O₄ NPs, P3HB@NiFe₂O₄ hybrid film, and the P3HB film was evaluated using human skin cells, keratinocytes, and fibroblasts, finding that the NPs are biocompatible. The P3HB film and hybrids are cytotoxic, which demonstrated that although P3HB is known and reported as a biocompatible polymer, under our work conditions, P3HB was cytotoxic. Its bactericidal effect could be related to this activity. Its films are bactericidal and cytotoxic to keratinocytes and fibroblasts, the first barrier of human skin. Despite this, the hybrid film of P3HB@NiFe₂O₄ presents synergy with the bactericidal effect between P3HB and NPs, increasing bacterial inhibition. In addition, NPs decrease the cytotoxicity of P3HB to keratinocytes. The methodology used in this work was successful in producing hybrid films with antibacterial activity. However, future challenges are generated to find relationships between NPs and P3HB that allow taking advantage of their bactericidal properties and do not compromise biocompatibility.

Keywords: poly-3-hydroxybutyrate, nanoparticles, hybrid film, antibacterial

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1812 Curcumin Derivatives as Potent Inhibitors of Inducible Nitric Oxide Synthase in Osteoarthritis: A Molecular Docking Study

Authors: F. Ambreen, A.Naheed

Abstract:

Osteoarthritis (OA) is a degenerative disorder affecting millions of people worldwide. Nitric oxide (NO) was found to play a catabolic role in the development of osteoarthritis. It is a toxic free radical gas generated during the metabolism of L-arginine by the enzyme Nitric oxide synthase (NOS). Inducible Nitric Oxide Synthase (iNOS) is one of the isoform of NOS, and its overexpression leads to the excessive formation of NO that results in pathophysiological joint conditions. Several synthetic anti-inflammatory drugs and inhibitors are present to date, but all showed side effects and complications. Therefore, the pursuit of natural disease-modifying drugs remains a top priority. Curcumin is an active component of turmeric, and the past few decades have witnessed intense research devoted to the antioxidant and anti-inflammatory properties of curcumin. The present study focused on curcumin and its derivatives in the search for new iNOS inhibitors for the treatment of osteoarthritis. We conducted a molecular docking study on curcumin and its four derivatives; cyclocurcumin, tetrahydrocurcumin, demethoxycurcumin and curcumin monoglucoside with iNOS using CLC Drug discovery work bench 3.02. We selected two co-crystallized ligands for this study; tetrahydrobiopterin and N-omega-propyl-L-arginine present in complex with the enzyme iNOS. Results showed the best binding affinity of N-omega-propyl-L-arginine with cyclocurcumin and curcumin monoglucoside that exhibit binding energies of -65.2 kcal/mol and -68 kcal/mol respectively. Whereas with tetrahydrobiopterin, best binding scores of -64.7 kcal/mol and -62.2 kcal/mol were found with tetrahydrocurcumin and demethoxycurcumin respectively. This information could open doors of research for the designing of novel drugs using herbs such as curcumin for the treatment of inflammatory joint diseases.

Keywords: curcumin, iNOS, molecular docking, osteoarthritis

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1811 Electrochemical Study of Prepared Cubic Fluorite Structured Titanium Doped Lanthanum Gallium Cerate Electrolyte for Low Temperature Solid Oxide Fuel Cell

Authors: Rida Batool, Faizah Altaf, Saba Nadeem, Afifa Aslam, Faisal Alamgir, Ghazanfar Abbas

Abstract:

Today, the need of the hour is to find out alternative renewable energy resources in order to reduce the burden on fossil fuels and prevent alarming environmental degradation. Solid oxide fuel cell (SOFC) is considered a good alternative energy conversion device because it is environmentally benign and supplies energy on demand. The only drawback associated with SOFC is its high operating temperature. In order to reduce operating temperature, different types of composite material are prepared. In this work, titanium doped lanthanum gallium cerate (LGCT) composite is prepared through the co-precipitation method as electrolyte and examined for low temperature SOFCs (LTSOFCs). The structural properties are analyzed by X-Ray Diffractometry (XRD) and Fourier Transform Infrared (FTIR) Spectrometry. The surface properties are investigated by Scanning Electron Microscopy (SEM). The electrolyte LGCT has the formula LGCTO₃ because it showed two phases La.GaO and Ti.CeO₂. The average particle size is found to be (32 ± 0.9311) nm. The ionic conductivity is achieved to be 0.073S/cm at 650°C. Arrhenius plots are drawn to calculate activation energy and found 2.96 eV. The maximum power density and current density are achieved at 68.25mW/cm² and 357mA/cm², respectively, at 650°C with hydrogen. The prepared material shows excellent ionic conductivity at comparatively low temperature, that makes it a potentially good candidate for LTSOFCs.

Keywords: solid oxide fuel cell, LGCTO₃, cerium composite oxide, ionic conductivity, low temperature electrolyte

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1810 La0.80Ag0.15MnO3 Magnetic Nanoparticles for Self-Controlled Magnetic Fluid Hyperthermia

Authors: Marian Mihalik, Kornel Csach, Martin Kovalik, Matúš Mihalik, Martina Kubovčíková, Maria Zentková, Martin Vavra, Vladimír Girman, Jaroslav Briančin, Marija Perovic, Marija Boškovic, Magdalena Fitta, Robert Pelka

Abstract:

Current nanomaterials for use in biomedicine are based mainly on iron oxides and on present knowledge on magnetic nanostructures. Manganites can represent another material which can be used optionally. Manganites and their unique electronic properties have been extensively studied in the last decades not only due to fundamental interest but to possible applications of colossal magnetoresistance, magnetocaloric effect, and ferroelectric properties. It was found that the oxygen-reduction reaction on perovskite oxide is intimately connected with metal ion e.g., orbital occupation. The effect of oxygen deviation from the stoichiometric composition on crystal structure was studied very carefully by many authors on LaMnO₃. Depending on oxygen content, the crystal structure changes from orthorhombic one to rhombohedric for oxygen content 3.1. In the case of hole-doped manganites, the change from the orthorhombic crystal structure, which is typical for La1-xCaxMnO3 based manganites, to the rhombohedric crystal structure (La1-xMxMnO₃ where M = K, Ag, and Sr based materials) results in an enormous increase of the Curie temperature. In our paper, we study the effect of oxygen content on crystal structure, thermal, and magnetic properties (including magnetocaloric effect) of La1-xAgxMnO₃nano particle system. The content of oxygen in samples was tuned by heat treatment in different thermal regimes and in various environment (air, oxygen, argon). Water nanosuspensions based on La0.80Ag0.15MnO₃ magnetic particles with the Curie temperature of about 43oC were prepared by two different approaches. First, by using a laboratory circulation mill for milling of powder in the presence of sodium dodecyl sulphate (SDS) and subsequent centrifugation. Second nanosuspension was prepared using an agate bowl, etching in citric acid and HNO3, ultrasound homogeniser, centrifugation, and dextran 40 kDA or 15 kDA as surfactant. Electrostatic stabilisation obtained by the first approach did not offer long term kinetic and aggregation colloidal stability and was unable to compensate for attractive forces between particles under a magnetic field. By the second approach, we prepared suspension oversaturated by dextran 40 kDA for steric stabilisation, with evidence of the presence of superparamagnetic behaviour. Low concentration of nanoparticles and not ideal coverage of nanoparticles impacting the stability of ferrofluids was the disadvantage of this approach. Strong steric stabilisation was observable at alcaic conditions under pH = ~10. Application of dextran 15 kDA leads to relatively stable ferrofluid with pH around physiological conditions, but desegregation of powder by HNO₃ was not effective enough, and the average size of fragments was to large of about 150 nm, and we did not see any signature of superparamagnetic behaviour. The prepared ferrofluids were characterised by scanning and transition microscope method, thermogravimetry, magnetization, and AC susceptibility measurements. Specific Absorption Rate measurements were undertaken on powder as well on ferrofluids in order to estimate the potential application of La₀.₈₀Ag₀.₁₅MnO₃ magnetic particles based ferrofluid for hyperthermia. Our complex study contains an investigation of biocompatibility and potential biohazard of this material.

Keywords: manganites, magnetic nanoparticles, oxygen content, magnetic phase transition, magnetocaloric effect, ferrofluid, hyperthermia

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1809 Technique for Online Condition Monitoring of Surge Arresters

Authors: Anil S. Khopkar, Kartik S. Pandya

Abstract:

Overvoltage in power systems is a phenomenon that cannot be avoided. However, it can be controlled to a certain extent. Power system equipment is to be protected against overvoltage to avoid system failure. Metal Oxide Surge Arresters (MOSA) are connected to the system for the protection of the power system against overvoltages. The MOSA will behave as an insulator under normal working conditions, where it offers a conductive path under voltage conditions. MOSA consists of zinc oxide elements (ZnO Blocks), which have non-linear V-I characteristics. ZnO blocks are connected in series and fitted in ceramic or polymer housing. This degrades due to the aging effect under continuous operation. Degradation of zinc oxide elements increases the leakage current flowing from the surge arresters. This Increased leakage current results in the increased temperature of the surge arrester, which further decreases the resistance of zinc oxide elements. As a result, leakage current increases, which again increases the temperature of a MOSA. This creates thermal runaway conditions for MOSA. Once it reaches the thermal runaway condition, it cannot return to normal working conditions. This condition is a primary cause of premature failure of surge arresters, as MOSA constitutes a core protective device for electrical power systems against transients. It contributes significantly to the reliable operation of the power system network. Hence, the condition monitoring of surge arresters should be done at periodic intervals. Online and Offline condition monitoring techniques are available for surge arresters. Offline condition monitoring techniques are not very popular as they require removing surge arresters from the system, which requires system shutdown. Hence, online condition monitoring techniques are very popular. This paper presents the evaluation technique for the surge arrester condition based on the leakage current analysis. Maximum amplitude of total leakage current (IT), Maximum amplitude of fundamental resistive leakage current (IR) and maximum amplitude of third harmonic resistive leakage current (I3rd) have been analyzed as indicators for surge arrester condition monitoring.

Keywords: metal oxide surge arrester (MOSA), over voltage, total leakage current, resistive leakage current

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1808 Production of Metal Matrix Composites with Diamond for Abrasive Cutting Resistance by Gas Infiltration Casting

Authors: Haydar S. Al Shabbani, M. Marshall, R. Goodall

Abstract:

Metal matrix composites (MMCs) have been explored for many applications for many decades. Recently, this includes investigations for thermal applications associated with electronics, such as in heat sinks. Here, to promote thermal conductivity, composites of a metal matrix with diamond particles are used. However, this class of composites has not yet been extensively examined for mechanical and tribological behavior, especially for applications that require extreme mechanical and tribological strength, such as the resistance to abrasive cutting. Therefore, this research seeks to develop a composite material with metal matrix and diamond particles which resist abrasive and cutting forces. The development progresses through a series of steps, exploring methods to process the material, understanding the mechanics of abrasive behavior and optimizing the composite structure to resist abrasive cutting. In processing, infiltration casting under gas pressure has been applied to molten aluminum to obtain a significant penetration of the metal into a preform of diamond particles. Different diamond particle sizes were used with different surface modifications (coated/uncoated), and to compare resulting composites with the same particle sizes. Al-1 wt.% Mg as a matrix alloy was utilised to investigate the possible effect of Mg on bonding phases during the infiltration process. The mechanical behavior and microstructure of the materials produced have been characterised. These tests showed that the surface modification of the diamond particles with a reactive material (Ti-coating) has an important role for enhancing the bonding between the aluminium matrix and diamond reinforcement as apparent under SEM observation. The effect of this improved bond is seen in the cutting resistance of the material.

Keywords: aluminium, composites, diamond, Ti-coated, tribology

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1807 Moringa olifera Curate The Toxic Potential of CuO Nanoparticles in Oreochromis mossambicus

Authors: Farhat Jabeen, Muhammad Asad

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The study assessed the curative potential of Moringa olifera seeds against copper oxide nanoparticles induced toxicity in Oreochromis mossambicus. In order to investigate the curative potential of M. olifera seeds, firstly we examine its chemical composition, secondary metabolites, and bioactive compounds including hydroxyl-cinnamic acids, flavanols and hydroxybenzoic acids through standard methods and high performance liquid chromatography. In current study, the potential sub-lethal toxic dose of CuO-NPs (0.12 mg/l) was investigated through pilot experiment and three non-lethal doses (low=32, medium=48 and high=96 mg/l) of M. olifera were selected on the basis of its LC50 value for O. mossambicus. The experimental fish, O. mossambicus (n=100 of approximately 20 g each) were procured from Manawan Fisheries Complex, Lahore, and acclimatized for two weeks in glass aquaria. Experiment was conducted in accordance with the guidelines of Institutional Animal Ethics Committee, Government College University Faisalabad, Pakistan. During acclimatization and experimental period, fish received the commercial fish feed at 2.5% body weight daily. In order to assess the curative effect of M. olifera against CuO NPs induced toxicity, O. mossambicus were randomly divided into five groups and were designated as control (C) without any treatment, positive control (G*) exposed to potential toxic dose of CuO-NPs at 0.12 mg/l, and three treated groups namely G1, G2, and G3 co-treated with 0.12 mg/l of CuO-NPs plus different doses of M. olifera seed extract at 32, 48, and 96 mg/l, respectively for 56 days. Fish were exposed to waterborne CuO NPs and M. olifera seed extract. CuO-NPs treatment was ceased after 28 days but the doses of M. olifera were continued for 56 days. Blood was taken after 28 and 56 days through caudal venipuncture. Liver and intestine were taken for oxidative stress and histological studies after 56 days. In M. olifera seeds, moisture contents, crude protein, lipids, carbohydrates and ash were recorded as 3.8, 37.83, 32.52, 46.12, and 7.75%, respectively on dry weight basis. Total energy was recorded as 627.36 kcal/100g. Qualitative analysis of M. olifera seeds showed the presence of terpenoids, saponins, flavonoids, alkaloids and phenolics, while its quantitative analysis showed the considerable amount of total phenolics, flavonoids, saponins, and alkaloids as 134.75, 170.15, 1.57, and 0.4 µg/mg, respectively. Analysis of bioactive compounds in M. olifera seeds showed the presence of hydroxy-cinnamic acids (6.07 µg/ml), flavanols (71.72 µg/ml), and hydroxyl benzoic acids (97.82 µg/ml). The results showed that M. oliefera seed extract at 48 and 56 mg/l was able to cure against the toxic effects of CuO-NPs. The significant changes were observed in G* and G1 for sero-hepatic enzymes, anti-oxidants and histological profile. The investigations of this study showed that M. olifera is a good curative agent against potential induced toxicity of CuO-NPs in O. mossambicus. The curative effect of M. olifera is attributed to the presence of higher amount of secondary metabolites and bioactive compounds. This study suggested the use of M. olifera to curate different ailments in fish and other organisms.

Keywords: CuO nanoparticles, curative, Moringa olifera, Oreochromis mossambicus

Procedia PDF Downloads 143
1806 Identification of Rice Quality Using Gas Sensors and Neural Networks

Authors: Moh Hanif Mubarok, Muhammad Rivai

Abstract:

The public's response to quality rice is very high. So it is necessary to set minimum standards in checking the quality of rice. Most rice quality measurements still use manual methods, which are prone to errors due to limited human vision and the subjectivity of testers. So, a gas detection system can be a solution that has high effectiveness and subjectivity for solving current problems. The use of gas sensors in testing rice quality must pay attention to several parameters. The parameters measured in this research are the percentage of rice water content, gas concentration, output voltage, and measurement time. Therefore, this research was carried out to identify carbon dioxide (CO₂), nitrous oxide (N₂O) and methane (CH₄) gases in rice quality using a series of gas sensors using the Neural Network method.

Keywords: carbon dioxide, dinitrogen oxide, methane, semiconductor gas sensor, neural network

Procedia PDF Downloads 45