Search results for: self-flux grown synthesis
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3113

Search results for: self-flux grown synthesis

1283 Hydrothermally Fabricated 3-D Nanostructure Metal Oxide Sensors

Authors: Mohammad Alenezi

Abstract:

Hierarchical nanostructures with higher dimensionality, consisting of nanostructure building blocks such as nanowires, nanotubes, or nanosheets are very attractive. They hold great properties like the high surface-to-volume ratio and well-ordered porous structures, which can be very challenging to attain for other mono-morphological nanostructures. Well-ordered hierarchical nanostructures with high surface-to-volume ratios facilitate gas diffusion into their surfaces as well as scattering of light. Therefore, hierarchical nanostructures are expected to perform highly as gas sensors. A multistage controlled hydrothermal synthesis method to fabricate high-performance single ZnO brushlike hierarchical nanostructure gas sensor from initial nanowires is reported. The performance of the sensor based on brush-like hierarchical nanostructure is analyzed and compared to that of a nanowire gas sensor. The hierarchical gas sensor demonstrated high sensitivity toward low concentration of acetone at high speed of response. The enhancement in the hierarchical sensor performance is attributed to the increased surface to volume ratio, reduction in dimensionality of the nanowire building blocks, formation of junctions between the initial nanowire and the secondary nanowires, and enhanced gas diffusion into the surfaces of the hierarchical nanostructures.

Keywords: metal oxide, nanostructure, hydrothermal, sensor

Procedia PDF Downloads 272
1282 Synthesis, Characterization, and Biological Evaluation of 1,3,4-Mercaptooxadiazole Ether Derivatives Analogs as Antioxidant, Cytotoxic, and Molecular Docking Studies

Authors: Desta Gebretekle Shiferaw, Balakrishna Kalluraya

Abstract:

Oxadiazoles and their derivatives with thioether functionalities represent a new and exciting class of physiologically active heterocyclic compounds. Several molecules with these moieties play a vital role in pharmaceuticals because of their diverse biological activities. This paper describes a new class of 1,3,4- oxadiazole-2-thioethers with acetophenone, coumarin, and N-phenyl acetamide residues (S-alkylation), with the hope that the addition of various biologically active molecules will have a synergistic effect on anticancer activity. The structure of the synthesized title compounds was determined by the combined methods of IR, proton-NMR, carbon-13-NMR, and mass spectrometry. Further, all the newly prepared molecules were assessed against their antioxidant activity. Furthermore, four compounds were assessed for their molecular docking interactions and cytotoxicity activity. The synthesized derivatives have shown moderate antioxidant activity compared to the standard BHA. The IC50 of the tilted molecules (11b, 11c, 13b, and 14b) observed for in vitro anti-cancer activities were 11.20, 15.73, 59.61, and 27.66 g/ml at 72-hour treatment time against the A549 cell lines, respectively. The tested compounds' biological evaluation showed that 11b is the most effective molecule in the series.

Keywords: antioxidant activity, cytotoxicity activity, molecular docking, 1, 3, 4-Oxadiazole-2 thioether derivatives

Procedia PDF Downloads 89
1281 Automatic Assignment of Geminate and Epenthetic Vowel for Amharic Text-to-Speech System

Authors: Tadesse Anberbir, Felix Bankole, Tomio Takara, Girma Mamo

Abstract:

In the development of a text-to-speech synthesizer, automatic derivation of correct pronunciation from the grapheme form of a text is a central problem. Particularly deriving phonological features which are not shown in orthography is challenging. In the Amharic language, geminates and epenthetic vowels are very crucial for proper pronunciation but neither is shown in orthography. In this paper, we proposed and integrated a morphological analyzer into an Amharic Text-to-Speech system, mainly to predict geminates and epenthetic vowel positions, and prepared a duration modeling method. Amharic Text-to-Speech system (AmhTTS) is a parametric and rule-based system that adopts a cepstral method and uses a source filter model for speech production and a Log Magnitude Approximation (LMA) filter as the vocal tract filter. The naturalness of the system after employing the duration modeling was evaluated by sentence listening test and we achieved an average Mean Opinion Score (MOS) 3.4 (68%) which is moderate. By modeling the duration of geminates and controlling the locations of epenthetic vowel, we are able to synthesize good quality speech. Our system is mainly suitable to be customized for other Ethiopian languages with limited resources.

Keywords: Amharic, gemination, speech synthesis, morphology, epenthesis

Procedia PDF Downloads 87
1280 The Antibacterial Efficacy of Gold Nanoparticles Derived from Gomphrena celosioides and Prunus amygdalus (Almond) Leaves on Selected Bacterial Pathogens

Authors: M. E. Abalaka, S. Y. Daniyan, S. O. Adeyemo, D. Damisa

Abstract:

Gold nanoparticles (AuNPs) have gained increasing interest in recent times. This is greatly due to their special features, which include unusual optical and electronic properties, high stability and biological compatibility, controllable morphology and size dispersion, and easy surface functionalization. In typical synthesis, AuNPs were produced by reduction of gold salt AuCl4 in an appropriate solvent. A stabilizing agent was added to prevent the particles from aggregating. The antibacterial activity of different sizes of gold nanoparticles was investigated against Staphylococcus aureus, Salmonella typhi and Pseudomonas pneumonia using the disk diffusion method in a Müeller–Hinton Agar. The Au-NPs were effective against all bacteria tested. That the Au-NPs were successfully synthesized in suspension and were used to study the antibacterial activity of the two medicinal plants against some bacterial pathogens suggests that Au-NPs can be employed as an effective bacteria inhibitor and may be an effective tool in medical field. The study clearly showed that the Au-NPs exhibiting inhibition towards the tested pathogenic bacteria in vitro could have the same effects in vivo and thus may be useful in the medical field if well researched into.

Keywords: gold nanoparticles, Gomphrena celesioides, Prunus amygdalus, pathogens

Procedia PDF Downloads 311
1279 Construction of Microbial Fuel Cells from Local Benthic Zones

Authors: Maria Luiza D. Ramiento, Maria Lissette D. Lucas

Abstract:

Electricity is said to serve as the backbone of modern technology. Considering this, electricity consumption has dynamically grown due to the continuous demand. An alternative producer of energy concerning electricity must therefore be given focus. Microbial fuel cell wholly characterizes a new method of renewable energy recovery: the direct conversion of organic matter to electricity using bacteria. Electricity is produced as fuel or new food is given to the bacteria. The study concentrated in determining the feasibility of electricity production from local benthic zones. Microbial fuel cells were constructed to harvest the possible electricity and to test the presence of electricity producing microorganisms. Soil samples were gathered from Calumpang River, Palawan Mangrove Forest, Rosario River and Batangas Port. Eleven modules were constructed for the different trials of the soil samples. These modules were made of cathode and anode chambers connected by a salt bridge. For 85 days, the harvested voltage was measured daily. No parameter is added for the first 24 days. For the next 61 days, acetic acid was included in the first and second trials of the modules. Each of the trials of the soil samples gave a positive result in electricity production.There were electricity producing microbes in local benthic zones. It is observed that the higher the organic content of the soil sample, the higher the electricity harvested from it. It is recommended to identify the specific species of the electricity-producing microorganism present in the local benthic zone. Complement experiments are encouraged like determining the kind of soil particles to test its effect on the amount electricity that can be harvested. To pursue the development of microbial fuel cells by building a closed circuit in it is also suggested.

Keywords: microbial fuel cell, benthic zone, electricity, reduction-oxidation reaction, bacteria

Procedia PDF Downloads 400
1278 Characterization of Electrical Transport across Ultra-Thin SrTiO₃ and BaTiO₃ Barriers in Tunnel Junctions

Authors: Henry Navarro, Martin Sirena, Nestor Haberkorn

Abstract:

We report the electrical transport through voltage-current curves (I-V) in tunnels junction GdBa₂Cu₃O₇-d/ insulator/ GdBa₂Cu₃O₇-d, and Nb/insulator/ GdBa₂Cu₃O₇-d is analyzed using a conducting atomic force microscope (CAFM) at room temperature. The measurements were obtained on tunnel junctions with different areas (900 μm², 400 μm² and 100 μm²). Trilayers with GdBa₂Cu₃O₇-d (GBCO) as the bottom electrode, SrTiO₃ (STO) or BaTiO₃ (BTO) as the insulator barrier (thicknesses between 1.6 nm and 4 nm), and GBCO or Nb as the top electrode were grown by DC sputtering on (100) SrTiO₃ substrates. For STO and BTO barriers, asymmetric IV curves at positive and negative polarization can be obtained using electrodes with different work function. The main difference is that the BTO is a ferroelectric material, while in the STO the ferroelectricity can be produced by stress or deformation at the interfaces. In addition, hysteretic IV curves are obtained for BTO barriers, which can be ascribed to a combined effect of the FE reversal switching polarization and an oxygen vacancy migration. For GBCO/ BTO/ GBCO heterostructures, the IV curves correspond to that expected for asymmetric interfaces, which indicates that the disorder affects differently the properties at the bottom and top interfaces. Our results show the role of the interface disorder on the electrical transport of conducting/ insulator/ conduction heterostructures, which is relevant for different applications, going from resistive switching memories (at room temperature) to Josephson junctions (at low temperatures). The superconducting transition of the GBCO electrode was characterized by electrical transport using the 4-prong configuration with low density of topological defects and with Tc over liquid N₂ can be obtained for thicknesses of 16 nm, our results demonstrate that GBCO films with an average root-mean-square (RMS) smaller than 1 nm and areas (up 100 um²) free of 3-D topological defects can be obtained.

Keywords: thin film, sputtering, conductive atomic force microscopy, tunnel junctions

Procedia PDF Downloads 155
1277 Manufacturing Anomaly Detection Using a Combination of Gated Recurrent Unit Network and Random Forest Algorithm

Authors: Atinkut Atinafu Yilma, Eyob Messele Sefene

Abstract:

Anomaly detection is one of the essential mechanisms to control and reduce production loss, especially in today's smart manufacturing. Quick anomaly detection aids in reducing the cost of production by minimizing the possibility of producing defective products. However, developing an anomaly detection model that can rapidly detect a production change is challenging. This paper proposes Gated Recurrent Unit (GRU) combined with Random Forest (RF) to detect anomalies in the production process in real-time quickly. The GRU is used as a feature detector, and RF as a classifier using the input features from GRU. The model was tested using various synthesis and real-world datasets against benchmark methods. The results show that the proposed GRU-RF outperforms the benchmark methods with the shortest time taken to detect anomalies in the production process. Based on the investigation from the study, this proposed model can eliminate or reduce unnecessary production costs and bring a competitive advantage to manufacturing industries.

Keywords: anomaly detection, multivariate time series data, smart manufacturing, gated recurrent unit network, random forest

Procedia PDF Downloads 118
1276 Biodiversity Interactions Between C3 and C4 Plants under Agroforestry Cropping System

Authors: Ezzat Abd El Lateef

Abstract:

Agroforestry means combining the management of trees with productive agricultural activities, especially in semiarid regions where crop yield increases are limited in agroforestry systems due to the fertility and microclimate improvements and the large competitive effect of trees with crops for water and nutrients, in order to assess the effect of agroforestry of some field crops with citrus trees as an approach to establish biodiversity in fruit tree plantations. Three field crops, i.e., maize, soybean and sunflower, were inter-planted with seedless orange trees (4*4 m) or were planted as solid plantings. The results for the trees indicated a larger fruit yield was obtained when soybean and sunflowers were interplant with citrus. Statistically significant effects (P<0.05) were found for maize grain and biological yields, with increased yields when grown as solid planting. There were no differences in the yields of soya bean and sunflower, where the yields were very similar between the two cropping systems. It is evident from the trials that agroforestry is an efficient concept to increase biodiversity through the interaction of trees with the interplant field crop species. Maize, unlike the other crops, was more sensitive to shade conditions under agroforestry practice and not preferred in the biodiversity system. The potential of agroforestry to improve or increase biodiversity is efficient as the understorey crops are usually C4 species, and the overstorey trees are invariably C3 species in agroforestry. Improvement in interplant species is most likely if the understorey crop is a C3 species, which are usually light saturated in the open, and partial shade may have little effect on assimilation or by a concurrent reduction in transpiration. It could be concluded that agroforestry is an efficient concept to increase biodiversity through the interaction of trees with the interplant field crop species. Some field crops could be employed successfully, like soybean or sunflowers, while others like maize are sensitive to incorporate in agroforestry system.

Keywords: agroforestry, field crops, C3 and C4 plants, yield

Procedia PDF Downloads 182
1275 Acetic Acid Assisted Phytoextraction of Chromium (Cr) by Energy Crop (Arundo donax L.) in Cr Contaminated Soils

Authors: Muhammad Iqbal, Hafiz Muhammad Tauqeer, Hamza Rafaqat, Muhammad Naveed, Muhammad Awais Irshad

Abstract:

Soil pollution with chromium (Cr) has become one of the most important concerns due to its toxicity for humans. To date, various remediation approaches have been employed for the remediation and management of Cr contaminated soils. Phytoextraction is an eco-friendly and emerging remediation approach which has gained attention due to several advantages over conventional remediation approach. The use of energy crops for phytoremediation is an emerging trend worldwide. These energy crops have high tolerance against various environmental stresses, the potential to grow in diverse ecosystems and high biomass production make them a suitable candidate for phytoremediation of contaminated soils. The removal efficiency of plants in phytoextraction depends upon several soil and plant factors including solubility, bioavailability and metal speciation in soils. A pot scale experiment was conducted to evaluate the phytoextraction potential of Arundo donax L. with the application of acetic acid (A.A) in Cr contaminated soils. Plants were grown in pots filled with 5 kg soils for 90 days. After 30 days plants acclimatization in pot conditions, plants were treated with various levels of Cr (2.5 mM, 5 mM, 7.5 mM, 10 mM) and A.A (Cr 2.5 mM + A.A 2.5 mM, Cr 5 mM + A.A 2.5 mM, Cr 7.5 mM + A.A 2.5 mM, Cr 10 mM + A.A 2.5 mM). The application of A.A significantly increased metal uptake and in roots and shoots of A. donax. This increase was observed at Cr 7.5 mM + A.A 2.5 mM but at high concentrations, visual symptoms of Cr toxicity were observed on leaves. Similarly, A.A applications also affect the activities of key enzymes including catalase (CAT), superoxidase dismutase (SOD), and ascorbate peroxidase (APX) in leaves of A. donax. Based on results it is concluded that the applications of A.A acid for phytoextraction is an alternative approach for the management of Cr affected soils and synthetic chelators should be replaced with organic acids.

Keywords: acetic acid, A. donax, chromium, energy crop, phytoextraction

Procedia PDF Downloads 388
1274 Synthesis and Thermoluminescence Study of Nanocrystalline Radiation Dosimeter CaSO₄:Ce/Sm/Dy

Authors: Anant Pandey, Kanika Sharma, Vibha Chopra, Shaila Bahl, Pratik Kumar, S. P. Lochab, Birendra Singh

Abstract:

This paper reports the thermoluminescence (TL) properties of nanocrystalline CaSO₄ activated by Ce, Sm, and Dy. TL properties are investigated by chiefly changing the dopant element and also by varying the concentration of the dopant elements (from 0.05 mol % to 0.5 mol %) so as to establish the optimized dopant concentration for each of the activators. The method of salt preparation used is the typical chemical co-precipitation method and the technique used for characterization of the prepared samples is the X-Ray Diffraction (XRD) technique. Further, the phosphors are irradiated with gamma radiation from Co-60 (1.25 MeV) source (dose range- 30 Gy to 500 Gy). The optimized concentration (vis-a-vis TL peak intensity) of activator for CaSO₄:Ce is found to be 0.2 mol %, for CaSO₄:Sm it is 0.1 mol % and for CaSO₄:Dy it is 0.2 mol %. Further, the primary study of the TL response curves for all the three phosphors confirms linearity in the studied dose range (i.e., 30 Gy to 500 Gy). Finally, CaSO₄:Dy was also studied for its energy dependence property which plays an important role in defining the utility of a phosphor for dosimetric applications. The range of doses used for the energy dependence study was from 30 Gy to 500 Gy from Cs-137 (0.662 MeV). The nano-phosphors showed potential to be used as radiation dosimeter in the studied range of gamma radiation and thus must be studied for a wider range of doses.

Keywords: gamma radiation, nanocrystalline, radiation dosimetry, thermoluminescence

Procedia PDF Downloads 175
1273 Metabolic Manipulation as a Strategy for Optimization of Biomass Productivity and Oil Content in the Microalgae Desmodesmus Sp.

Authors: Ivan A. Sandoval Salazar, Silvia F. Valderrama

Abstract:

The microalgae oil emerges as a promising source of raw material for many industrial applications. Thus, this study had as a main focus on the cultivation of the microalgae species Desmodesmus sp. in laboratory scale with a view to maximizing biomass production and triglyceride content in the lipid fraction. Initially, culture conditions were selected to optimize biomass production, which was subsequently subjected to nutritional stress by varying nitrate and phosphate concentrations in order to increase the content and productivity of fatty acids. The culture medium BOLD 3N, nitrate and phosphate, light intensity 250,500 and 1000 μmol photons.m².s⁻¹, photoperiod of 12:12 were evaluated. Under the best conditions of the tests, a maximum cell division of 1.13 div.dia⁻¹ was obtained on the sixth day of culture, beginning of the exponential phase, and a maximum concentration of 8.42x107 cell.mL⁻¹ and dry biomass of 3.49 gL⁻¹ on the 20th day, in the stationary phase. The lipid content in the first stage of culture was approximately 8% after 12 days and at the end of the culture in the stationary phase ranged from 12% to 16% (20 days). In the microalgae grown at 250 μmol fotons.m2.s-1 the fatty acid profile was mostly polyunsaturated (52%). The total of unsaturated fatty acids, identified in this species of microalga, reached values between 70 and 75%, being qualified for use in the food and pharmaceutical industry. In addition, this study showed that the cultivation conditions influenced mainly the production of polyunsaturated fatty acids, with the predominance of γ-linolenic acid. However, in the cultures submitted to the highest the intensity of light (1000 μmol photons.m².s⁻¹) and low concentrations of nitrate and phosphate, saturated and monounsaturated fatty acids, which present greater oxidative stability, were identified mainly (60 to 70 %) being qualified for the production of biodiesel and for oleochemistry.

Keywords: microalgae, Desmodesmus sp, fatty acids, biodiesel

Procedia PDF Downloads 148
1272 System Identification and Quantitative Feedback Theory Design of a Lathe Spindle

Authors: M. Khairudin

Abstract:

This paper investigates the system identification and design quantitative feedback theory (QFT) for the robust control of a lathe spindle. The dynamic of the lathe spindle is uncertain and time variation due to the deepness variation on cutting process. System identification was used to obtain the dynamics model of the lathe spindle. In this work, real time system identification is used to construct a linear model of the system from the nonlinear system. These linear models and its uncertainty bound can then be used for controller synthesis. The real time nonlinear system identification process to obtain a set of linear models of the lathe spindle that represents the operating ranges of the dynamic system. With a selected input signal, the data of output and response is acquired and nonlinear system identification is performed using Matlab to obtain a linear model of the system. Practical design steps are presented in which the QFT-based conditions are formulated to obtain a compensator and pre-filter to control the lathe spindle. The performances of the proposed controller are evaluated in terms of velocity responses of the the lathe machine spindle in corporating deepness on cutting process.

Keywords: lathe spindle, QFT, robust control, system identification

Procedia PDF Downloads 543
1271 Schiff Bases of Isatin and Admantane-1-Carbohydrazide: Synthesis, Characterization, and Anticonvulsant Activity

Authors: Hind O. Osman, Tilal Elsaman, Bashir A. Yousef, Esraa Elhadi, Aimun A. E. Ahmed, Eyman Mohamed Eltayib, Malik Suliman Mohamed, Magdi Awadalla Mohamed

Abstract:

Epilepsy is the most common neurological condition and cause of substantial morbidity and mortality. In the present study, the molecular hybridization tool was adopted to obtain six Schiff bases of isatin and adamantane-1-carbohydrazide (18–23). Then, their anticonvulsant activity was evaluated using a pentylenetetrazole- (PTZ-) induced seizure model using phenobarbitone as a positive control. Our findings showed that compounds 18–23 provided significant protection against PTZ-induced seizure, and maximum activities were associated with compound 23. Moreover, all investigated compounds increased the latency of induced convulsion and reduced the duration of epilepsy, with compound 23 being the best. Interestingly, most of the synthesized molecules showed a reduction in neurological symptoms and severity of the seizure. Molecular docking studies suggest GABA-A receptor as a potential target, and in silico ADME screening revealed that the pharmaceutical properties of compound 23 are within the specified limit. Thus, compound 23 was identified as a promising candidate that warrants further drug discovery processes.

Keywords: isatin and adamantane, anticonvulsant activity, PTZ-induced seizure, molecular docking

Procedia PDF Downloads 207
1270 An Antibacterial Dental Restorative Containing 3,4-Dichlorocrotonolactone: Synthesis, Formulation and Evaluation

Authors: Dong Xie, Leah Howard, Yiming Weng

Abstract:

The objective of this study was to synthesize and characterize 5-acryloyloxy-3,4-dichlorocrotonolactone (a furanone derivative), use this derivative to modify a dental restorative, and study the effect of the derivative on the antibacterial activity and compressive strength of the formed restorative. In this study, a furanone derivative was synthesized, characterized, and used to formulate a dental restorative. Compressive strength (CS) and S. mutans viability were used to evaluate the mechanical strength and antibacterial activity of the formed restorative. The fabricated restorative specimens were photocured and conditioned in distilled water at 37oC for 24 h, followed by direct testing for CS or/and incubating with S. mutans for 48 h for antibacterial testing. The results show that the modified dental restorative showed a significant antibacterial activity without substantially decreasing the mechanical strengths. With addition of the antibacterial derivative up to 30%, the restorative kept its original CS nearly unchanged but showed a significant antibacterial activity with 68% reduction in the S. mutans viability. Furthermore, the antibacterial function of the modified restorative was not affected by human saliva. The aging study also indicates that the modified restorative may have a long-lasting antibacterial function. It is concluded that this experimental antibacterial restorative may potentially be developed into a clinically attractive dental filling restorative due to its high mechanical strength and antibacterial function.

Keywords: antibacterial, dental restorative, compressive strength, S. mutans viability

Procedia PDF Downloads 326
1269 Electrocatalytic Amino Acid Synthesis from Biomass-Derivable Keto Acids over Ball-Milled Carbon Nanotubes

Authors: Yiying Xiao, Chia Wei Lim, Jinquan Chang, Qixin Yuan, Lei Wang, Ning Yan

Abstract:

Electrocatalytic reductive amination (ERA) offers an attractive way to make organonitrogen chemicals from renewable feedstock. Here, we report carbon nanotube (CNT) as an effective catalyst for the ERA of biomass-derivable α-keto acids into amino acids using NH₃ as the nitrogen source. Through a facile ball milling (BM) treatment, the intrinsic defects in the CNTs were increased while the electrocatalytic activity of CNTs converting 2-ketoglutaric acid into glutamic acid was enhanced by approximately seven times. A high Faradaic efficiency (FE) of ~90% with a corresponding glutamic acid formation rate up to 180.9 mmol•g⁻¹𝒸ₐₜt•h⁻¹ was achieved, and ~60% molar yield of glutamic acid was obtained after 8 h of electrolysis. Electrokinetic analyses indicate that the BM-CNTs catalysed ERA exhibits first-order dependences on the substrate and NH₃, with a rate-determining step (RDS) involving the first electron transfer. Following this protocol, a number of amino acids were prepared with moderate to high FEs and formation rates. Significantly, we synthesised long carbon chain amino acids, which typically face lower yields using the existing methods.

Keywords: amino acids, carbon nanotubes, electrocatalysis, reductive amination, α-keto acids

Procedia PDF Downloads 83
1268 A Time and Frequency Dependent Study of Low Intensity Microwave Radiation Induced Endoplasmic Reticulum Stress and Alteration of Autophagy in Rat Brain

Authors: Ranjeet Kumar, Pravin Suryakantrao Deshmukh, Sonal Sharma, Basudev Banerjee

Abstract:

With the tremendous increase in exposure to radiofrequency microwaves emitted by mobile phones, globally public awareness has grown with regard to the potential health hazards of microwaves on the nervous system in the brain. India alone has more than one billion mobile users out of 4.3 billion globally. Our studies have suggested that radio frequency able to affect neuronal alterations in the brain, and hence, affecting cognitive behaviour. However, adverse effect of low-intensity microwave exposure with endoplasmic reticulum stress and autophagy has not been evaluated yet. In this study, we explore whether low-intensity microwave induces endoplasmic reticulum stress and autophagy with varying frequency and time duration in Wistar rat. Ninety-six male Wistar rat were divided into 12 groups of 8 rats each. We studied at 900 MHz, 1800 MHz, and 2450 MHz frequency with reference to sham-exposed group. At the end of the exposure, the rats were sacrificed to collect brain tissue and expression of CHOP, ATF-4, XBP-1, Bcl-2, Bax, LC3 and Atg-4 gene was analysed by real-time PCR. Significant fold change (p < 0.05) of gene expression was found in all groups of 1800 MHz and 2450 MHz exposure group in comparison to sham exposure group. In conclusion, the microwave exposure able to induce ER stress and modulate autophagy. ER (endoplasmic reticulum) stress and autophagy vary with increasing frequency as well as the duration of exposure. Our results suggested that microwave exposure is harmful to neuronal health as it induces ER stress and hampers autophagy in neuron cells and thereby increasing the neuron degeneration which impairs cognitive behaviour of experimental animals.

Keywords: autophagy, ER stress, microwave, nervous system, rat

Procedia PDF Downloads 131
1267 An Efficient FPGA Realization of Fir Filter Using Distributed Arithmetic

Authors: M. Iruleswari, A. Jeyapaul Murugan

Abstract:

Most fundamental part used in many Digital Signal Processing (DSP) application is a Finite Impulse Response (FIR) filter because of its linear phase, stability and regular structure. Designing a high-speed and hardware efficient FIR filter is a very challenging task as the complexity increases with the filter order. In most applications the higher order filters are required but the memory usage of the filter increases exponentially with the order of the filter. Using multipliers occupy a large chip area and need high computation time. Multiplier-less memory-based techniques have gained popularity over past two decades due to their high throughput processing capability and reduced dynamic power consumption. This paper describes the design and implementation of highly efficient Look-Up Table (LUT) based circuit for the implementation of FIR filter using Distributed arithmetic algorithm. It is a multiplier less FIR filter. The LUT can be subdivided into a number of LUT to reduce the memory usage of the LUT for higher order filter. Analysis on the performance of various filter orders with different address length is done using Xilinx 14.5 synthesis tool. The proposed design provides less latency, less memory usage and high throughput.

Keywords: finite impulse response, distributed arithmetic, field programmable gate array, look-up table

Procedia PDF Downloads 457
1266 A Suggestive Framework for Measuring the Effectiveness of Social Media: An Irish Tourism Study

Authors: Colm Barcoe, Garvan Whelan

Abstract:

Over the past five years, visitations of American holidaymakers to Ireland have grown exponentially owing to the online strategies of Tourism Ireland, a Destination Marketer (DMO) with a meagre budget which is extended by their understanding of best practices to maximise their monetary allowance. This suggested framework incorporates a range of Key Performance Indicators (KPI’s) such as financial, marketing, and operational that offer a scale of measurement from which the Irish DMO can monitor the success of each promotional campaign when targeting the US and Canada. These are presented not as final solutions but rather as suggestions based on empirical evidence obtained from both primary and secondary sources. This research combines the wisdom extracted through qualitative methodologies with the objective of understanding the processes that drive both emergent and agile strategies. The Study extends the work relative to performance and examines the role of social media in the context of promoting Ireland to North America. There are two main themes that are identified and analysed in this investigation, these are the approach of the DMO when advocating Ireland as a brand and the benefits of digital platforms set against a proposed scale of KPIs, such as destination marketing, brand positioning, and identity development. The key narrative of this analysis is to focus on the power of social media when capitalising upon marketing opportunities, operating on a relatively small budget. This will always be a relevant theme of discussion due to the responsibility of an organisation like Tourism Ireland operating under the restraints imposed by government funding. The overall conclusions of this research may help inform those concerned with the implementing of social media strategies develop clearer models of measurement when promoting a destination to North America. The suggestions of this study will benefit small and medium enterprises particularly.

Keywords: destination marketing, framework, measure, performance

Procedia PDF Downloads 154
1265 A Review of Emerging Technologies in Antennas and Phased Arrays for Avionics Systems

Authors: Muhammad Safi, Abdul Manan

Abstract:

In recent years, research in aircraft avionics systems (i.e., radars and antennas) has grown revolutionary. Aircraft technology is experiencing an increasing inclination from all mechanical to all electrical aircraft, with the introduction of inhabitant air vehicles and drone taxis over the last few years. This develops an overriding need to summarize the history, latest trends, and future development in aircraft avionics research for a better understanding and development of new technologies in the domain of avionics systems. This paper focuses on the future trends in antennas and phased arrays for avionics systems. Along with the general overview of the future avionics trend, this work describes the review of around 50 high-quality research papers on aircraft communication systems. Electric-powered aircraft have been a hot topic in the modern aircraft world. Electric aircraft have supremacy over their conventional counterparts. Due to increased drone taxi and urban air mobility, fast and reliable communication is very important, so concepts of Broadband Integrated Digital Avionics Information Exchange Networks (B-IDAIENs) and Modular Avionics are being researched for better communication of future aircraft. A Ku-band phased array antenna based on a modular design can be used in a modular avionics system. Furthermore, integrated avionics is also emerging research in future avionics. The main focus of work in future avionics will be using integrated modular avionics and infra-red phased array antennas, which are discussed in detail in this paper. Other work such as reconfigurable antennas and optical communication, are also discussed in this paper. The future of modern aircraft avionics would be based on integrated modulated avionics and small artificial intelligence-based antennas. Optical and infrared communication will also replace microwave frequencies.

Keywords: AI, avionics systems, communication, electric aircrafts, infra-red, integrated avionics, modular avionics, phased array, reconfigurable antenna, UAVs

Procedia PDF Downloads 81
1264 Adjustments of Mechanical and Hydraulic Properties of Wood Formed under Environmental Stresses

Authors: B. Niez, B. Moulia, J. Dlouha, E. Badel

Abstract:

Trees adjust their development to the environmental conditions they experience. Storms events of last decades showed that acclimation of trees to mechanical stresses due to wind is a very important process that allows the trees to sustain for long years. In the future, trees will experience new wind patterns, namely, more often strong winds and fewer daily moderate winds. Moreover, these patterns will go along with drought periods that may interact with the capacity of trees to adjust their growth to mechanical stresses due to wind. It is necessary to understand the mechanisms of wood functional acclimations to environmental conditions in order to predict their behaviour and in order to give foresters and breeders the relevant tools to adapt their forest management. This work aims to study how trees adjust the mechanical and hydraulic functions of their wood to environmental stresses and how this acclimation may be beneficial for the tree to resist to future stresses. In this work, young poplars were grown under controlled climatic conditions that include permanent environmental stress (daily mechanical stress of the stem by bending and/or hydric stress). Then, the properties of wood formed under these stressed conditions were characterized. First, hydraulic conductivity and sensibility to cavitation were measured at the tissue level in order to evaluate the changes in water transport capacity. Secondly, bending tests and Charpy impact tests were carried out at the millimetric scale to locally measure mechanical parameters such as elastic modulus, elastic limit or rupture energy. These experimental data allow evaluating the impacts of mechanical and water stress on the wood material. At the stem level, they will be merged in an integrative model in order to evaluate the beneficial aspect of wood acclimation for trees.

Keywords: acclimation, environmental stresses, hydraulics, mechanics, wood

Procedia PDF Downloads 204
1263 A Supramolecular Cocrystal of 2-Amino-4-Chloro-6-Methylpyrimidine with 4-Methylbenzoic Acid: Synthesis, Structural Determinations and Quantum Chemical Investigations

Authors: Nuridayanti Che Khalib, Kaliyaperumal Thanigaimani, Suhana Arshad, Ibrahim Abdul Razak

Abstract:

The 1:1 co-crystal of 2-amino-4-chloro-6-methylpyrimidine (2A4C6MP) with 4-methylbenzoic acid (4MBA) (I) has been prepared by slow evaporation method in methanol, which was crystallized in monoclinic C2/c space group, Z = 8, a = 28.431 (2) Å, b = 7.3098 (5) Å, c = 14.2622 (10) Å, and β = 109.618 (3)°. The presence of unionized –COOH functional group in co-crystal I was identified both by spectral methods (1H and 13C NMR, FTIR) and X-ray diffraction structural analysis. The 2A4C6MP molecule interact with the carboxylic group of the respective 4MBA molecule through N—H⋯O and O—H⋯N hydrogen bonds, forming a cyclic hydrogen –bonded motif R22(8). The crystal structure was stabilized by Npyrimidine-H⋯O=C and C=O-H⋯Npyrimidine types hydrogen bonding interactions. Theoretical investigations have been computed by HF and density function (B3LYP) method with 6-311+G(d,p) basis set. The vibrational frequencies together with 1H and 13C NMR chemical shifts have been calculated on the fully optimized geometry of co-crystal I. Theoretical calculations are in good agreement with the experimental results. Solvent-free formation of this co-crystal I is confirmed by powder X-ray diffraction analysis.

Keywords: supramolecular co-crystal, 2-amino-4-chloro-6-methylpyrimidine, Harthree-Fock and DFT studies, spectroscopic analysis

Procedia PDF Downloads 309
1262 Contentious Issues Concerning the Methodology of Using the Lexical Approach in Teaching ESP

Authors: Elena Krutskikh, Elena Khvatova

Abstract:

In tertiary settings expanding students’ vocabulary and teaching discursive competence is seen as one of the chief goals of a professional development course. However, such a focus often is detrimental to students’ cognitive competences, such as analysis, synthesis, and creative processing of information, and deprives students of motivation for self-improvement and self-development of language skills. The presentation is going to argue that in an ESP course special attention should be paid to reading/listening which can promote understanding and using the language as a tool for solving significant real world problems, including professional ones. It is claimed that in the learning process it is necessary to maintain a balance between the content and the linguistic aspect of the educational process as language acquisition is inextricably linked with mental activity and the need to express oneself is a primary stimulus for using a language. A study conducted among undergraduates indicates that they place a premium on quality materials that motivate them and stimulate their further linguistic and professional development. Thus, more demands are placed on study materials that should contain new information for students and serve not only as a source of new vocabulary but also prepare them for real tasks related to professional activities.

Keywords: critical reading, english for professional development, english for specific purposes, high order thinking skills, lexical approach, vocabulary acquisition

Procedia PDF Downloads 167
1261 Nutritional Advantages of Millet (Panucum Miliaceum L) and Opportunities for Its Processing as Value Added Foods

Authors: Fatima Majeed Almonajim

Abstract:

Panucum miliaceum L is a plant from the genus Gramineae, In the world, millets are regarded as a significant grain, however, they are very little exploited. Millet grain is abundant in nutrients and health-beneficial phenolic compounds, making it suitable as food and feed. The plant has received considerable attention for its high content of phenolic compounds, low glycemic index, the presence of unsaturated fats and lack of gluten which are beneficial to human health, and thus, have made the plant being effective in treating celiac disease, diabetes, lowering blood lipids (cholesterol) and preventing tumors. Moreover, the plant requires little water to grow, a property that is worth considering. This study provides an overview of the nutritional and health benefits provided by millet types grown in 2 areas Iraq and Iran, aiming to compare the effect of climate on the components of millet. In this research, millet samples collected from the both Babylon (Iraqi) and Isfahan (Iranian) types were extracted and after HPTLC, the resulted pattern of the two samples were compared. As a result, the Iranian millet showed more terpenoid compounds than Iraqi millet, and therefore, Iranian millet has a higher priority than Iraqi millet in increasing the human body's immunity. On the other hand, in view of the number of essential amino acids, the Iraqi millet contains more nutritional value compared to the Iranian millet. Also, due to the higher amount of histidine in the Iranian millet, compiled to the lack of gluten found from previous studies, we came to the conclusion that the addition of millet in the diet of children, more specifically those children with irritable bowel syndrome, can be considered beneficial. Therefore, as a component of dairy products, millet can be used in preparing food for children such as dry milk.

Keywords: HPTLC, phytochemicals, specialty foods, Panucum miliaceum L, nutrition

Procedia PDF Downloads 95
1260 Substitution of Formaldehyde in Phenolic Resins with Innovative and Bio-Based Vanillin Derived Compounds

Authors: Sylvain Caillol, Ghislain David

Abstract:

Phenolic resins are industrially used in a wide range of applications from commodity and construction materials to high-technology aerospace industry. They are mainly produced from the reaction between phenolic compounds and formaldehyde. Nevertheless, formaldehyde is a highly volatile and hazardous compound, classified as a Carcinogenic, Mutagenic and Reprotoxic chemical (CMR). Vanillin is a bio-based and non-toxic aromatic aldehyde compound obtained from the abundant lignin resources. Also, its aromaticity is very interesting for the synthesis of phenolic resins with high thermal stability. However, because of the relatively low reactivity of its aldehyde function toward phenolic compounds, it has never been used to synthesize phenolic resins. We developed innovative functionalization reactions and designed new bio-based aromatic aldehyde compounds from vanillin. Those innovative compounds present improved reactivity toward phenolic compounds compared to vanillin. Moreover, they have target structures to synthesize highly cross-linked phenolic resins with high aromatic densities. We have obtained phenolic resins from substituted vanillin, thus without the use of any aldehyde compound classified as CMR. The analytical tests of the cured resins confirmed that those bio-based resins exhibit high levels of performance with high thermal stability and high rigidity properties

Keywords: phenolic resins, formaldehyde-free, vanillin, bio-based, non-toxic

Procedia PDF Downloads 272
1259 Ripening Conditions Suitable for Marketing of Winter Squash ‘Bochang’

Authors: Do Su Park, Sang Jun Park, Cheon Soon Jeong

Abstract:

This study was performed in order to investigate the optimum ripening conditions for the marketing of Squash. Research sample 'Bochang' was grown at Hongcheonin in Gangwon province in August 2014. Ripening the samples were stored under the conditions of 25℃, 30℃, and 35℃ with the humidity RH70 ± 5%. They were checked every 3 days for 21 days. The respiration rate, water loss, hardness, coloration, the contents of soluble solids, starch, total sugar were evaluated after storage. Respiration rate was reduced in all treatments with longer storage period. Water loss was increased in the higher temperature. The 13% water loss was found at 35℃ on 21st storage day. The store initially 25℃ and 30℃ Hardness 47N and the ripening 21 days decreased slightly. On the other hand, in the case of 35℃ showed a large reduction than 25℃ and 30℃. Soluble solid contents were increased with longer ripening period. 30℃ and 35℃ was highest ripening 15 days. In the case of 25℃, it was highest on 21th day. The higher the temperature, the higher the soluble solids content are. 25℃ and 30℃ Coloration was increased rapidly until the ripening 12 days. In case of 35℃, continued increase up to 21 days. 25℃ and 30℃ showed no differences. Meanwhile, in case of 35℃, appearance quality was reduced in Occurrence of yellowing phenomenon of pericarp occurs from after ripening for 9 days. The coloration of fruit flesh is increase until after ripening for 9 days and decrease from after ripening for 9 days. There was no significant difference depending on the conditions of temperature. The higher the temperature, the lower the content of the starch. In case of 30℃ and 35℃, was reduced with longer storage period. 25℃ was minimal content change. Total sugar was increased in all treatments with longer storage period. The higher the temperature, the higher the amount of total sugar content is. Therefore, at 25℃ for 18-21 days and at 30℃ for 12-15 days is suitable for ripening.

Keywords: marketing, ripening, temperature, winter squash

Procedia PDF Downloads 598
1258 The Dynamic of Nₘᵢₙ in Clay Loam Cambisol in Alternative Farming

Authors: Danute Jablonskyte-Rasce, Laura Masilionyte

Abstract:

The field experiments of different farming systems were conducted at Joniškėlis Experimental Station of the Lithuanian Research Centre for Agriculture and Forestry in 2006–2016. The soil of the experimental site was Endocalcari-Endohypogleyic Cambisol (CMg-n-w-can). The research was designed to identify the effects of dry matter and nitrogen accumulated in the above-ground biomass of various catch crops grown after winter wheat on soil mineral nitrogen variation during the autumn and spring period in the presence of intensive leaching complex. Research was done in the soil differing in humus status in the organic and sustainable cropping systems by growing various plant mixtures as catch crops: narrow-leafed lupine (Lupinus angustifolius L.) and oil radish (Raphanus sativus var. Oleifera L.), white mustard (Sinapis alba L.) and buckwheat (Fagopyrum exculentum Moench.) and white mustard as a sole crop. All crop and soil management practices have shown optimal efficiency in late autumn – stubble breaking, catch crops and straw used during the post-harvest period of the main crops, reduced Nmin migration into deeper (40–80 cm) soil layer. The greatest Nmin reduction in the 0–40 cm soil layer during the period from late autumn to early spring was identified in the sustainable cropping system having applied N30 for the promotion of straw mineralization and with no catch crops cultivation. The sustainable cropping system, having applied N30 for straw mineralization and growing white mustard in combination with buckwheat as catch crops, Nmin difference in the spring compared with its status in the autumn in the soil low and moderate in humus was lower by 70.1% and 34.2%, respectively.

Keywords: soil nitrogen, catch crops, ecological and sustainable farming systems, Cambisol

Procedia PDF Downloads 259
1257 Spectroscopy Investigation of Ni0.5Zn0.5Fe2O4 Nano Ferrite Prepared by Soft Mechanochemical Synthesis

Authors: Z. Ž. Lazarević, Č. Jovalekić, V. N. Ivanovski, N. Ž. Romčević

Abstract:

Nickel-zinc ferrite, Ni0.5Zn0.5Fe2O4 was prepared by mechanochemical route in a planetary ball mill starting from mixture of the appropriate quantities of the Ni(OH)2, Zn(OH)2 and Fe(OH)3 hydroxide powders. In order to monitor the progress of chemical reaction and confirm phase formation, powder samples obtained after 5 h and 10 h of milling were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), IR, Raman and Mössbauer spectroscopy. It is shown that the soft mechanochemical method, i.e. mechanochemical activation of hydroxides, produces high quality single phase Ni0.5Zn0.5Fe2O4 samples in much more efficient way. From the IR spectroscopy of single phase samples it is obvious that energy of modes depends on the ratio of cations. It is obvious that all samples have more than 5 Raman active modes predicted by group theory in the normal spinel structure. Deconvolution of measured spectra allows one to conclude that all complex bands in the spectra are made of individual peaks with the intensities that vary from spectrum to spectrum. The deconvolution of Raman spectra alows to separate contributions of different cations to a particular type of vibration and to estimate the degree of inversion.

Keywords: ferrite, X-ray diffraction, infrared spectroscopy, Raman spectroscopy, Mössbauer spectroscopy

Procedia PDF Downloads 505
1256 Synthesis of 3,4-Dihydro-1H-Quinoxalin-2-Ones and 1H‑Quinolin-2-Ones and Evaluation of Their Anti-Bacterial Activity

Authors: Ali Amiri, Arash Esfandiari, Elham Zarenezhad

Abstract:

We report here an efficient and rapid method for the preparation of 3,4-dihydro-1H-quinoxalin-2-ones and 1H‑quinolin-2-ones that involves grinding of o-, m-, or p‑phenylenediamine and three dialkyl acetylenedicarboxylates using a pestle and mortar. This solvent-free approach requires only a few minutes of reaction time. This type of reaction is expected to be the most economical method since neither catalyst nor solvent is used. Finally, all synthesised compounds were screened for antimicrobial activity against two Gram-positive bacteria (Pseudomonas aeruginosa PTCC 1077, Escherichia coli PTCC1330) and two Gram-negative bacteria (Staphylococcus aureus PTCC 1133, Bacillus cereus PTCC 1015) and their activity. Compared with gentamycin and ampicillin as reference drugs for Gram-negative and Gram-positive bacteria, respectively. The minimum inhibitory concentration (MIC) of the synthesised compounds and reference drugs were determined by the microdilution method. Good antibacterial activity was observed for 3,4-dihydro-1H-quinoxalin-2-ones against all species of Gram-positive and Gram-negative bacteria, and1H‑quinolin-2-ones showed good antibacterial activity against two Gram-positive bacteria.

Keywords: quinolin, quinoxalin, anti-bacterial activity, minimum inhibitory concentration (MIC)

Procedia PDF Downloads 334
1255 Study of Self-Assembled Photocatalyst by Metal-Terpyridine Interactions in Polymer Network

Authors: Dong-Cheol Jeong, Jookyung Lee, Yu Hyeon Ro, Changsik Song

Abstract:

The design and synthesis of photo-active polymeric systems are important in regard to solar energy harvesting and utilization. In this study, we synthesized photo-active polymer, thin films, and polymer gel via iterative self-assembly using reversible metal-terpyridine (M-tpy) interactions. The photocurrent generated in the polymeric thin films with Zn(II) was much higher than those of other films. Apparent diffusion rate constant (kapp) was measured for the electron hopping process via potential-step chronoamperometry. As a result, the kapp for the polymeric thin films with Zn(II) was almost two times larger than those with other metal ions. We found that the anodic photocurrents increased with the inclusion of the multi-walled carbon nanotube (MWNT) layer. Inclusion of MWNTs can provide efficient electron transfer pathways. In addition, polymer gel based on interactions between terpyridine and metal ions was shown the photocatalytic activity. Interestingly, in the Mg-terpyridine gel, the reaction rate of benzylamine to imine photo-oxidative coupling was faster than Fe-terpyridine gel because the Mg-terpyridine gel has two steps electron transfer pathway but Fe-terpyridine gel has three steps electron transfer pathway.

Keywords: terpyridine, photocatalyst, self-assebly, metal-ligand

Procedia PDF Downloads 308
1254 The Clarification of Palm Oil Wastewater Treatment by Coagulant Composite from Palm Oil Ash

Authors: Rewadee Anuwattana, Narumol Soparatana, Pattamaphorn Phuangngamphan, Worapong Pattayawan, Atiporn Jinprayoon, Saroj Klangkongsap, Supinya Sutthima

Abstract:

In this work focus on clarification in palm oil wastewater treatment by using coagulant composite from palm oil ash. The design of this study was carried out by two steps; first, synthesis of new coagulant composite from palm oil ash which was fused by using Al source combined with Fe source and form to the crystal by the hydrothermal crystallization process. The characterization of coagulant composite from palm oil ash was analyzed by advanced instruments, and The pattern was analyzed by X-ray Diffraction (XRD), chemical composition by X-Ray Fluorescence (XRFS) and morphology characterized by SEM. The second step, the clarification wastewater treatment efficiency of synthetic coagulant composite, was evaluated by coagulation/flocculation process based on the COD, turbidity, phosphate and color removal of wastewater from palm oil factory by varying the coagulant dosage (1-8 %w/v) with no adjusted pH and commercial coagulants (Alum, Ferric Chloride and poly aluminum chloride) which adjusted the pH (6). The results found that the maximum removal of 6% w/v of synthetic coagulant from palm oil ash can remove COD, turbidity, phosphate and color was 88.44%, 93.32%, 93.32% and 93.32%, respectively. The experiments were compared using 6% w/v of commercial coagulants (Alum, Ferric Chloride and Polyaluminum Chloride) can remove COD of 74.29%, 71.43% and 57.14%, respectively.

Keywords: coagulation, coagulant, wastewater treatment, waste utilization, palm oil ash

Procedia PDF Downloads 191