Search results for: binary phase
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5014

Search results for: binary phase

3214 Design of an Innovative Geothermal Heat Pump with a PCM Thermal Storage

Authors: Emanuele Bonamente, Andrea Aquino

Abstract:

This study presents an innovative design for geothermal heat pumps with the goal of maximizing the system efficiency (COP - Coefficient of Performance), reducing the soil use (e.g. length/depth of geothermal boreholes) and initial investment costs. Based on experimental data obtained from a two-year monitoring of a working prototype implemented for a commercial building in the city of Perugia, Italy, an upgrade of the system is proposed and the performance is evaluated via CFD simulations. The prototype was designed to include a thermal heat storage (i.e. water), positioned between the boreholes and the heat pump, acting as a flywheel. Results from the monitoring campaign show that the system is still capable of providing the required heating and cooling energy with a reduced geothermal installation (approx. 30% of the standard length). In this paper, an optimization of the system is proposed, re-designing the heat storage to include phase change materials (PCMs). Two stacks of PCMs, characterized by melting temperatures equal to those needed to maximize the system COP for heating and cooling, are disposed within the storage. During the working cycle, the latent heat of the PCMs is used to heat (cool) the water used by the heat pump while the boreholes independently cool (heat) the storage. The new storage is approximately 10 times smaller and can be easily placed close to the heat pump in the technical room. First, a validation of the CFD simulation of the storage is performed against experimental data. The simulation is then used to test possible alternatives of the original design and it is finally exploited to evaluate the PCM-storage performance for two different configurations (i.e. single- and double-loop systems).

Keywords: geothermal heat pump, phase change materials (PCM), energy storage, renewable energies

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3213 Linking Disgust and Misophonia: The Role of Mental Contamination

Authors: Laurisa Peters, Usha Barahmand, Maria Stalias-Mantzikos, Naila Shamsina, Kerry Aguero

Abstract:

In the current study, the authors sought to examine whether the links between moral and sexual disgust and misophonia are mediated by mental contamination. An internationally diverse sample of 283 adults (193 females, 76 males, and 14 non-binary individuals) ranging in age from 18 to 60 years old was recruited from online social media platforms and survey recruitment sites. The sample completed an online battery of scales that consisted of the New York Misophonia Scale, State Mental Contamination Scale, and the Three-Domain Disgust Scale. The hypotheses were evaluated using a series of mediations performed using the PROCESS add-on in SPSS. Correlations were found between emotional and aggressive-avoidant reactions in misophonia, mental contamination, pathogen disgust, and sexual disgust. Moral disgust and non-aggressive reactions in misophonia failed to correlate significantly with any of the other constructs. Sexual disgust had direct and indirect effects, while pathogen disgust had only direct effects on aspects of misophonia. These findings partially support our hypothesis that mental contamination mediates the link between disgust propensity and misophonia while also confirming that pathogen-based disgust is not associated with mental contamination. Findings imply that misophonia is distinct from obsessive-compulsive disorder. Further research into the conceptualization of moral disgust is warranted.

Keywords: misophonia, moral disgust, pathogen disgust, sexual disgust, mental contamination

Procedia PDF Downloads 94
3212 Engineers 'Write' Job Description: Development of English for Specific Purposes (ESP)-Based Instructional Materials for Engineering Students

Authors: Marjorie Miguel

Abstract:

Globalization offers better career opportunities hence demands more competent professionals efficient for the job. With the transformation of the world industry from competition to collaboration coupled with the rapid development in the field of science and technology, engineers need not only to be technically proficient, but also multilingual-skilled: two characteristics that a global engineer possesses. English often serves as the global language between people from different cultures being the medium mostly used in international business. Ironically, most universities worldwide adapt engineering curriculum heavily built around the language of mathematics not realizing that the goal of an engineer is not only to create and design, but more importantly to promote his creations and designs to the general public through effective communication. This premise led to some developments in the teaching process of English subjects in the tertiary level which include the integration of the technical knowledge related to the area of specialization of the students in the English subjects that they are taking. This is also known as English for Specific Purposes. This study focused on the development of English for Specific Purposes-Based Instructional Materials for Engineering Students of Bulacan State University (BulSU). The materials were tailor-made in which the contents and structure were designed to meet the specific needs of the students as well as the industry. Based on the needs analysis, the needs of the students and the industry were determined to make the study descriptive in nature. The major respondents included fifty engineering students and ten professional engineers from selected institutions. The needs analysis was done and the results showed the common writing difficulties of the students and the writing skills needed among the engineers in the industry. The topics in the instructional materials were established after the needs analysis was conducted. Simple statistical treatment including frequency distribution, percentages, mean, standard deviation, and weighted mean were used. The findings showed that the greatest number of the respondents had an average proficiency rating in writing, and the much-needed skills that must be developed by the engineers are directly related to the preparation and presentation of technical reports about their projects, as well as to the different communications they transmit to their colleagues and superiors. The researcher undertook the following phases in the development of the instructional materials: a design phase, development phase, and evaluation phase. Evaluations are given by some college instructors about the instructional materials generally helped in its usefulness and significance making the study beneficial not only as a career enhancer for BulSU engineering students, but also creating the university one of the educational institutions ready for the new millennium.

Keywords: English for specific purposes, instructional materials, needs analysis, write (right) job description

Procedia PDF Downloads 237
3211 Multi-Criteria Optimal Management Strategy for in-situ Bioremediation of LNAPL Contaminated Aquifer Using Particle Swarm Optimization

Authors: Deepak Kumar, Jahangeer, Brijesh Kumar Yadav, Shashi Mathur

Abstract:

In-situ remediation is a technique which can remediate either surface or groundwater at the site of contamination. In the present study, simulation optimization approach has been used to develop management strategy for remediating LNAPL (Light Non-Aqueous Phase Liquid) contaminated aquifers. Benzene, toluene, ethyl benzene and xylene are the main component of LNAPL contaminant. Collectively, these contaminants are known as BTEX. In in-situ bioremediation process, a set of injection and extraction wells are installed. Injection wells supply oxygen and other nutrient which convert BTEX into carbon dioxide and water with the help of indigenous soil bacteria. On the other hand, extraction wells check the movement of plume along downstream. In this study, optimal design of the system has been done using PSO (Particle Swarm Optimization) algorithm. A comprehensive management strategy for pumping of injection and extraction wells has been done to attain a maximum allowable concentration of 5 ppm and 4.5 ppm. The management strategy comprises determination of pumping rates, the total pumping volume and the total running cost incurred for each potential injection and extraction well. The results indicate a high pumping rate for injection wells during the initial management period since it facilitates the availability of oxygen and other nutrients necessary for biodegradation, however it is low during the third year on account of sufficient oxygen availability. This is because the contaminant is assumed to have biodegraded by the end of the third year when the concentration drops to a permissible level.

Keywords: groundwater, in-situ bioremediation, light non-aqueous phase liquid, BTEX, particle swarm optimization

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3210 Challenging Barriers to the Evolution of the Saudi Animation Industry Life-Cycle

Authors: Ohud Alharbi, Emily Baines

Abstract:

The animation industry is one of the creative industries that have attracted recent historiographical attention. However, there has been very limited research on Saudi Arabian and wider Arabian animation industries, while there are a large number of studies that have covered this issue for North America, Europe and East Asia. The existing studies show that developed countries such as USA, Japan and the UK have reached the Maturity stage in their animation industry life-cycle. On the other hand, developing countries that are still in the Introduction phase of the industry life-cycle face challenges to improve their industry. Saudi Arabia is one of the countries whose animation industry is still in its infancy. Thus, the aim of this paper is to address the main barriers that hinder the evolution of the industry life-cycle for Saudi animation – challenges that are also relevant to many other early stage industries in developing countries. These barriers have been analysed using the early mobility barriers defined by Porter, to provide a conceptual structure for defining recommendations to enable the transition to a strong Growth phase industry. This study utilized qualitative methods to collect data, which involved in-depth interviews, document analysis and observations. It also undertook a comparative case study approach to investigate the animation industry life-cycle, with three selected case studies that have a more developed industry than Saudi animation. Case studies include: the United Kingdom, which represents a Mature animation industry; Egypt, which represents an established Growth stage industry; and the United Arab of Emirates, which is an early Growth stage industry. This study suggests adopting appropriate strategies that arise as findings from the comparative case studies, to overcome barriers and facilitate the growth of the Saudi animation industry.

Keywords: barriers, industry life-cycle, Saudi animation, industry

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3209 Generation of Charged Nanoparticles and Their Contribution to the Thin Film and Nanowire Growth during Chemical Vapour Deposition

Authors: Seung-Min Yang, Seong-Han Park, Sang-Hoon Lee, Seung-Wan Yoo, Chan-Soo Kim, Nong-Moon Hwang

Abstract:

The theory of charged nanoparticles suggested that in many Chemical Vapour Depositions (CVD) processes, Charged Nanoparticles (CNPs) are generated in the gas-phase and become a building block of thin films and nanowires. Recently, the nanoparticle-based crystallization has become a big issue since the growth of nanorods or crystals by the building block of nanoparticles was directly observed by transmission electron microscopy observations in the liquid cell. In an effort to confirm charged gas-phase nuclei, that might be generated under conventional processing conditions of thin films and nanowires during CVD, we performed an in-situ measurement using differential mobility analyser and particle beam mass spectrometer. The size distribution and number density of CNPs were affected by process parameters such as precursor flow rate and working temperature. It was shown that many films and nanostructures, which have been believed to grow by individual atoms or molecules, actually grow by the building blocks of such charged nuclei. The electrostatic interaction between CNPs and the growing surface induces the self-assembly into films and nanowires. In addition, the charge-enhanced atomic diffusion makes CNPs liquid-like quasi solid. As a result, CNPs tend to land epitaxial on the growing surface, which results in the growth of single crystalline nanowires with a smooth surface.

Keywords: chemical vapour deposition, charged nanoparticle, electrostatic force, nanostructure evolution, differential mobility analyser, particle beam mass spectrometer

Procedia PDF Downloads 448
3208 Stock Market Prediction Using Convolutional Neural Network That Learns from a Graph

Authors: Mo-Se Lee, Cheol-Hwi Ahn, Kee-Young Kwahk, Hyunchul Ahn

Abstract:

Over the past decade, deep learning has been in spotlight among various machine learning algorithms. In particular, CNN (Convolutional Neural Network), which is known as effective solution for recognizing and classifying images, has been popularly applied to classification and prediction problems in various fields. In this study, we try to apply CNN to stock market prediction, one of the most challenging tasks in the machine learning research. In specific, we propose to apply CNN as the binary classifier that predicts stock market direction (up or down) by using a graph as its input. That is, our proposal is to build a machine learning algorithm that mimics a person who looks at the graph and predicts whether the trend will go up or down. Our proposed model consists of four steps. In the first step, it divides the dataset into 5 days, 10 days, 15 days, and 20 days. And then, it creates graphs for each interval in step 2. In the next step, CNN classifiers are trained using the graphs generated in the previous step. In step 4, it optimizes the hyper parameters of the trained model by using the validation dataset. To validate our model, we will apply it to the prediction of KOSPI200 for 1,986 days in eight years (from 2009 to 2016). The experimental dataset will include 14 technical indicators such as CCI, Momentum, ROC and daily closing price of KOSPI200 of Korean stock market.

Keywords: convolutional neural network, deep learning, Korean stock market, stock market prediction

Procedia PDF Downloads 423
3207 Fuel Quality of Biodiesel from Chlorella protothecoides Microalgae Species

Authors: Mukesh Kumar, Mahendra Pal Sharma

Abstract:

Depleting fossil fuel resources coupled with serious environmental degradation has led to the search for alternative resources for biodiesel production as a substitute of Petro-diesel. Currently, edible, non-edible oils and microalgal plant species are cultivated for biodiesel production. Looking at the demerits of edible and non-edible oil resources, the focus is being given to grow microalgal species having high oil productivities, less maturity time and less land requirement. Out of various microalgal species, Chlorella protothecoides is considered as the most promising species for biodiesel production owing to high oil content (58 %), faster growth rate (24–48 h) and high biomass productivity (1214 mg/l/day). The present paper reports the results of optimization of reaction parameters of transesterification process as well as the kinetics of transesterification with 97% yield of biodiesel. The measurement of fuel quality of microalgal biodiesel shows that the biodiesel exhibit very good oxidation stability (O.S) of 7 hrs, more than ASTM D6751 (3 hrs) and EN 14112 (6 hrs) specifications. The CP and PP of 0 and -3 °C are finding as per ASTM D 2500-11 and ASTM D 97-12 standards. These results show that the microalgal biodiesel does not need any enhancement in O.S & CFP and hence can be recommended to be directly used as MB100 or its blends into diesel engine operation. Further, scope is available for the production of binary blends using poor quality biodiesel for engine operation.

Keywords: fuel quality, methyl ester yield, microalgae, transesterification

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3206 Modeling of a Pilot Installation for the Recovery of Residual Sludge from Olive Oil Extraction

Authors: Riad Benelmir, Muhammad Shoaib Ahmed Khan

Abstract:

The socio-economic importance of the olive oil production is significant in the Mediterranean region, both in terms of wealth and tradition. However, the extraction of olive oil generates huge quantities of wastes that may have a great impact on land and water environment because of their high phytotoxicity. Especially olive mill wastewater (OMWW) is one of the major environmental pollutants in olive oil industry. This work projects to design a smart and sustainable integrated thermochemical catalytic processes of residues from olive mills by hydrothermal carbonization (HTC) of olive mill wastewater (OMWW) and fast pyrolysis of olive mill wastewater sludge (OMWS). The byproducts resulting from OMWW-HTC treatment are a solid phase enriched in carbon, called biochar and a liquid phase (residual water with less dissolved organic and phenolic compounds). HTC biochar can be tested as a fuel in combustion systems and will also be utilized in high-value applications, such as soil bio-fertilizer and as catalyst or/and catalyst support. The HTC residual water is characterized, treated and used in soil irrigation since the organic and the toxic compounds will be reduced under the permitted limits. This project’s concept includes also the conversion of OMWS to a green diesel through a catalytic pyrolysis process. The green diesel is then used as biofuel in an internal combustion engine (IC-Engine) for automotive application to be used for clean transportation. In this work, a theoretical study is considered for the use of heat from the pyrolysis non-condensable gases in a sorption-refrigeration machine for pyrolysis gases cooling and condensation of bio-oil vapors.

Keywords: biomass, olive oil extraction, adsorption cooling, pyrolisis

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3205 Principal Component Analysis in Drug-Excipient Interactions

Authors: Farzad Khajavi

Abstract:

Studies about the interaction between active pharmaceutical ingredients (API) and excipients are so important in the pre-formulation stage of development of all dosage forms. Analytical techniques such as differential scanning calorimetry (DSC), Thermal gravimetry (TG), and Furrier transform infrared spectroscopy (FTIR) are commonly used tools for investigating regarding compatibility and incompatibility of APIs with excipients. Sometimes the interpretation of data obtained from these techniques is difficult because of severe overlapping of API spectrum with excipients in their mixtures. Principal component analysis (PCA) as a powerful factor analytical method is used in these situations to resolve data matrices acquired from these analytical techniques. Binary mixtures of API and interested excipients are considered and produced. Peaks of FTIR, DSC, or TG of pure API and excipient and their mixtures at different mole ratios will construct the rows of the data matrix. By applying PCA on the data matrix, the number of principal components (PCs) is determined so that it contains the total variance of the data matrix. By plotting PCs or factors obtained from the score of the matrix in two-dimensional spaces if the pure API and its mixture with the excipient at the high amount of API and the 1:1mixture form a separate cluster and the other cluster comprise of the pure excipient and its blend with the API at the high amount of excipient. This confirms the existence of compatibility between API and the interested excipient. Otherwise, the incompatibility will overcome a mixture of API and excipient.

Keywords: API, compatibility, DSC, TG, interactions

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3204 Effect of pH-Dependent Surface Charge on the Electroosmotic Flow through Nanochannel

Authors: Partha P. Gopmandal, Somnath Bhattacharyya, Naren Bag

Abstract:

In this article, we have studied the effect of pH-regulated surface charge on the electroosmotic flow (EOF) through nanochannel filled with binary symmetric electrolyte solution. The channel wall possesses either an acidic or a basic functional group. Going beyond the widely employed Debye-Huckel linearization, we develop a mathematical model based on Nernst-Planck equation for the charged species, Poisson equation for the induced potential, Stokes equation for fluid flow. A finite volume based numerical algorithm is adopted to study the effect of key parameters on the EOF. We have computed the coupled governing equations through the finite volume method and our results found to be in good agreement with the analytical solution obtained from the corresponding linear model based on low surface charge condition or strong electrolyte solution. The influence of the surface charge density, reaction constant of the functional groups, bulk pH, and concentration of the electrolyte solution on the overall flow rate is studied extensively. We find the effect of surface charge diminishes with the increase in electrolyte concentration. In addition for strong electrolyte, the surface charge becomes independent of pH due to complete dissociation of the functional groups.

Keywords: electroosmosis, finite volume method, functional group, surface charge

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3203 Hydrochemical Assessment and Quality Classification of Water in Torogh and Kardeh Dam Reservoirs, North-East Iran

Authors: Mojtaba Heydarizad

Abstract:

Khorasan Razavi is the second most important province in north-east of Iran, which faces a water shortage crisis due to recent droughts and huge water consummation. Kardeh and Torogh dam reservoirs in this province provide a notable part of Mashhad metropolitan (with more than 4.5 million inhabitants) potable water needs. Hydrochemical analyses on these dam reservoirs samples demonstrate that MgHCO3 in Kardeh and CaHCO3 and to lower extent MgHCO3 water types in Torogh dam reservoir are dominant. On the other hand, Gibbs binary diagram demonstrates that rock weathering is the main factor controlling water quality in dam reservoirs. Plotting dam reservoir samples on Mg2+/Na+ and HCO3-/Na+ vs. Ca2+/ Na+ diagrams demonstrate evaporative and carbonate mineral dissolution is the dominant rock weathering ion sources in these dam reservoirs. Cluster Analyses (CA) also demonstrate intense role of rock weathering mainly (carbonate and evaporative minerals dissolution) in water quality of these dam reservoirs. Studying water quality by the U.S. National Sanitation Foundation (NSF) WQI index NSF-WQI, Oregon Water Quality Index (OWQI) and Canadian Water Quality Index DWQI index show moderate and good quality.

Keywords: hydrochemistry, water quality classification, water quality indexes, Torogh and Kardeh dam reservoir

Procedia PDF Downloads 253
3202 Fast Aerodynamic Evaluation of Transport Aircraft in Early Phases

Authors: Xavier Bertrand, Alexandre Cayrel

Abstract:

The early phase of an aircraft development is instrumental as it really drives the potential of a new concept. Any weakness in the high-level design (wing planform, moveable surfaces layout etc.) will be extremely difficult and expensive to recover later in the aircraft development process. Aerodynamic evaluation in this very early development phase is driven by two main criteria: a short lead-time to allow quick iterations of the geometrical design, and a high quality of the calculations to get an accurate & reliable assessment of the current status. These two criteria are usually quite contradictory. Actually, short lead time of a couple of hours from end-to-end can be obtained with very simple tools (semi-empirical methods for instance) although their accuracy is limited, whereas higher quality calculations require heavier/more complex tools, which obviously need more complex inputs as well, and a significantly longer lead time. At this point, the choice has to be done between accuracy and lead-time. A brand new approach has been developed within Airbus, aiming at obtaining quickly high quality evaluations of the aerodynamic of an aircraft. This methodology is based on a joint use of Surrogate Modelling and a lifting line code. The Surrogate Modelling is used to get the wing sections characteristics (e.g. lift coefficient vs. angle of attack), whatever the airfoil geometry, the status of the moveable surfaces (aileron/spoilers) or the high-lift devices deployment. From these characteristics, the lifting line code is used to get the 3D effects on the wing whatever the flow conditions (low/high Mach numbers etc.). This methodology has been applied successfully to a concept of medium range aircraft.

Keywords: aerodynamics, lifting line, surrogate model, CFD

Procedia PDF Downloads 355
3201 The Effectiveness of Multiphase Flow in Well- Control Operations

Authors: Ahmed Borg, Elsa Aristodemou, Attia Attia

Abstract:

Well control involves managing the circulating drilling fluid within the wells and avoiding kicks and blowouts as these can lead to losses in human life and drilling facilities. Current practices for good control incorporate predictions of pressure losses through computational models. Developing a realistic hydraulic model for a good control problem is a very complicated process due to the existence of a complex multiphase region, which usually contains a non-Newtonian drilling fluid and the miscibility of formation gas in drilling fluid. The current approaches assume an inaccurate flow fluid model within the well, which leads to incorrect pressure loss calculations. To overcome this problem, researchers have been considering the more complex two-phase fluid flow models. However, even these more sophisticated two-phase models are unsuitable for applications where pressure dynamics are important, such as in managed pressure drilling. This study aims to develop and implement new fluid flow models that take into consideration the miscibility of fluids as well as their non-Newtonian properties for enabling realistic kick treatment. furthermore, a corresponding numerical solution method is built with an enriched data bank. The research work considers and implements models that take into consideration the effect of two phases in kick treatment for well control in conventional drilling. In this work, a corresponding numerical solution method is built with an enriched data bank. Software STARCCM+ for the computational studies to study the important parameters to describe wellbore multiphase flow, the mass flow rate, volumetric fraction, and velocity of each phase. Results showed that based on the analysis of these simulation studies, a coarser full-scale model of the wellbore, including chemical modeling established. The focus of the investigations was put on the near drill bit section. This inflow area shows certain characteristics that are dominated by the inflow conditions of the gas as well as by the configuration of the mud stream entering the annulus. Without considering the gas solubility effect, the bottom hole pressure could be underestimated by 4.2%, while the bottom hole temperature is overestimated by 3.2%. and without considering the heat transfer effect, the bottom hole pressure could be overestimated by 11.4% under steady flow conditions. Besides, larger reservoir pressure leads to a larger gas fraction in the wellbore. However, reservoir pressure has a minor effect on the steady wellbore temperature. Also as choke pressure increases, less gas will exist in the annulus in the form of free gas.

Keywords: multiphase flow, well- control, STARCCM+, petroleum engineering and gas technology, computational fluid dynamic

Procedia PDF Downloads 116
3200 Integration of Hybrid PV-Wind in Three Phase Grid System Using Fuzzy MPPT without Battery Storage for Remote Area

Authors: Thohaku Abdul Hadi, Hadyan Perdana Putra, Nugroho Wicaksono, Adhika Prajna Nandiwardhana, Onang Surya Nugroho, Heri Suryoatmojo, Soedibjo

Abstract:

Access to electricity is now a basic requirement of mankind. Unfortunately, there are still many places around the world which have no access to electricity, such as small islands, where there could potentially be a factory, a plantation, a residential area, or resorts. Many of these places might have substantial potential for energy generation such us Photovoltaic (PV) and Wind turbine (WT), which can be used to generate electricity independently for themselves. Solar energy and wind power are renewable energy sources which are mostly found in nature and also kinds of alternative energy that are still developing in a rapid speed to help and meet the demand of electricity. PV and Wind has a characteristic of power depend on solar irradiation and wind speed based on geographical these areas. This paper presented a control methodology of hybrid small scale PV/Wind energy system that use a fuzzy logic controller (FLC) to extract the maximum power point tracking (MPPT) in different solar irradiation and wind speed. This paper discusses simulation and analysis of the generation process of hybrid resources in MPP and power conditioning unit (PCU) of Photovoltaic (PV) and Wind Turbine (WT) that is connected to the three-phase low voltage electricity grid system (380V) without battery storage. The capacity of the sources used is 2.2 kWp PV and 2.5 kW PMSG (Permanent Magnet Synchronous Generator) -WT power rating. The Modeling of hybrid PV/Wind, as well as integrated power electronics components in grid connected system, are simulated using MATLAB/Simulink.

Keywords: fuzzy MPPT, grid connected inverter, photovoltaic (PV), PMSG wind turbine

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3199 Nanoscale Photo-Orientation of Azo-Dyes in Glassy Environments Using Polarized Optical Near-Field

Authors: S. S. Kharintsev, E. A. Chernykh, S. K. Saikin, A. I. Fishman, S. G. Kazarian

Abstract:

Recent advances in improving information storage performance are inseparably linked with circumvention of fundamental constraints such as the supermagnetic limit in heat assisted magnetic recording, charge loss tolerance in solid-state memory and the Abbe’s diffraction limit in optical storage. A substantial breakthrough in the development of nonvolatile storage devices with dimensional scaling has been achieved due to phase-change chalcogenide memory, which nowadays, meets the market needs to the greatest advantage. A further progress is aimed at the development of versatile nonvolatile high-speed memory combining potentials of random access memory and archive storage. The well-established properties of light at the nanoscale empower us to use them for recording optical information with ultrahigh density scaled down to a single molecule, which is the size of a pit. Indeed, diffraction-limited optics is able to record as much information as ~1 Gb/in2. Nonlinear optical effects, for example, two-photon fluorescence recording, allows one to decrease the extent of the pit even more, which results in the recording density up to ~100 Gb/in2. Going beyond the diffraction limit, due to the sub-wavelength confinement of light, pushes the pit size down to a single chromophore, which is, on average, of ~1 nm in length. Thus, the memory capacity can be increased up to the theoretical limit of 1 Pb/in2. Moreover, the field confinement provides faster recording and readout operations due to the enhanced light-matter interaction. This, in turn, leads to the miniaturization of optical devices and the decrease of energy supply down to ~1 μW/cm². Intrinsic features of light such as multimode, mixed polarization and angular momentum in addition to the underlying optical and holographic tools for writing/reading, enriches the storage and encryption of optical information. In particular, the finite extent of the near-field penetration, falling into a range of 50-100 nm, gives the possibility to perform 3D volume (layer-to-layer) recording/readout of optical information. In this study, we demonstrate a comprehensive evidence of isotropic-to-homeotropic phase transition of the azobenzene-functionalized polymer thin film exposed to light and dc electric field using near-field optical microscopy and scanning capacitance microscopy. We unravel a near-field Raman dichroism of a sub-10 nm thick epoxy-based side-chain azo-polymer films with polarization-controlled tip-enhanced Raman scattering. In our study, orientation of azo-chromophores is controlled with a bias voltage gold tip rather than light polarization. Isotropic in-plane and homeotropic out-of-plane arrangement of azo-chromophores in glassy environment can be distinguished with transverse and longitudinal optical near-fields. We demonstrate that both phases are unambiguously visualized by 2D mapping their local dielectric properties with scanning capacity microscopy. The stability of the polar homeotropic phase is strongly sensitive to the thickness of the thin film. We make an analysis of α-transition of the azo-polymer by detecting a temperature-dependent phase jump of an AFM cantilever when passing through the glass temperature. Overall, we anticipate further improvements in optical storage performance, which approaches to a single molecule level.

Keywords: optical memory, azo-dye, near-field, tip-enhanced Raman scattering

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3198 Adaptive Swarm Balancing Algorithms for Rare-Event Prediction in Imbalanced Healthcare Data

Authors: Jinyan Li, Simon Fong, Raymond Wong, Mohammed Sabah, Fiaidhi Jinan

Abstract:

Clinical data analysis and forecasting have make great contributions to disease control, prevention and detection. However, such data usually suffer from highly unbalanced samples in class distributions. In this paper, we target at the binary imbalanced dataset, where the positive samples take up only the minority. We investigate two different meta-heuristic algorithms, particle swarm optimization and bat-inspired algorithm, and combine both of them with the synthetic minority over-sampling technique (SMOTE) for processing the datasets. One approach is to process the full dataset as a whole. The other is to split up the dataset and adaptively process it one segment at a time. The experimental results reveal that while the performance improvements obtained by the former methods are not scalable to larger data scales, the later one, which we call Adaptive Swarm Balancing Algorithms, leads to significant efficiency and effectiveness improvements on large datasets. We also find it more consistent with the practice of the typical large imbalanced medical datasets. We further use the meta-heuristic algorithms to optimize two key parameters of SMOTE. Leading to more credible performances of the classifier, and shortening the running time compared with the brute-force method.

Keywords: Imbalanced dataset, meta-heuristic algorithm, SMOTE, big data

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3197 Advanced Phosphorus-Containing Polymer Materials towards Eco-Friendly Flame Retardant Epoxy Thermosets

Authors: Ionela-Daniela Carja, Diana Serbezeanu, Tachita Vlad-Bubulac, Corneliu Hamciuc

Abstract:

Nowadays, epoxy materials are extensively used in ever more areas and under ever more demanding environmental conditions due to their remarkable combination of properties, light weight and ease of processing. However, these materials greatly increase the fire risk due to their flammability and possible release of toxic by-products as a result of their chemical composition which consists mainly from carbon and hydrogen atoms. Therefore, improving the fire retardant behaviour to prevent the loss of life and property is of particular concern among government regulatory bodies, consumers and manufacturers alike. Modification of epoxy resins with organophosphorus compounds, as reactive flame retardants or additives, is the key to achieving non-flammable advanced epoxy materials. Herein, a detailed characterization of fire behaviour for a series of phosphorus-containing epoxy thermosets is reported. A carefully designed phosphorus flame retardant additive was simply blended with a bifunctional bisphenol-A based epoxy resin. Further thermal cross-linking in the presence of various aminic hardeners led to eco-friendly flame retardant epoxy resins. The type of hardener, concentration of flame retardant additive, compatibility between the components of the mixture, char formation and morphology, thermal stability, flame retardant mechanisms were investigated. It was found that even a very low content of phosphorus introduced into the epoxy matrix increased the limiting oxygen index value to about 30%. In addition, the peak of the heat release rate value decreased up to 45% as compared to the one of the neat epoxy system. The main flame retardant mechanism was the condensed-phase one as revealed by SEM and XPS measurements.

Keywords: condensed-phase mechanism, eco-friendly phosphorus flame retardant, epoxy resin, thermal stability

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3196 Separation of Oryzanol from Rice Bran Oil Using Silica: Equilibrium of Batch Adsorption

Authors: A. D. Susanti, W. B. Sediawan, S. K. Wirawan, Budhijanto, Ritmaleni

Abstract:

Rice bran oil contains significant amounts of oryzanol, a natural antioxidant that considered has higher antioxidant activity than vitamin E (tocopherol). Oryzanol reviewed has several health properties and interested in pharmacy, nutrition, and cosmetics. For practical usage, isolation and purification would be necessary due to the low concentration of oryzanol in crude rice bran oil (0.9-2.9%). Batch chromatography has proved as a promising process for the oryzanol recovery, but productivity was still low and scale-up processes of industrial interest have not yet been described. In order to improve productivity of batch chromatography, a continuous chromatography design namely Simulated Moving Bed (SMB) concept have been proposed. The SMB concept has interested for continuous commercial scale separation of binary system (oryzanol and rice bran oil), and rice bran oil still obtained as side product. Design of SMB chromatography for oryzanol separation requires quantification of its equilibrium. In this study, equilibrium of oryzanol separation conducted in batch adsorption using silica as the adsorbent and n-hexane/acetone (9:1) as the eluent. Three isotherm models, namely the Henry, Langmuir, and Freundlich equations, have been applied and modified for the experimental data to establish appropriate correlation for each sample. It turned out that the model quantitatively describe the equilibrium experimental data and will directed for design of SMB chromatography.

Keywords: adsorption, equilibrium, oryzanol, rice bran oil, simulated moving bed

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3195 3D Human Reconstruction over Cloud Based Image Data via AI and Machine Learning

Authors: Kaushik Sathupadi, Sandesh Achar

Abstract:

Human action recognition modeling is a critical task in machine learning. These systems require better techniques for recognizing body parts and selecting optimal features based on vision sensors to identify complex action patterns efficiently. Still, there is a considerable gap and challenges between images and videos, such as brightness, motion variation, and random clutters. This paper proposes a robust approach for classifying human actions over cloud-based image data. First, we apply pre-processing and detection, human and outer shape detection techniques. Next, we extract valuable information in terms of cues. We extract two distinct features: fuzzy local binary patterns and sequence representation. Then, we applied a greedy, randomized adaptive search procedure for data optimization and dimension reduction, and for classification, we used a random forest. We tested our model on two benchmark datasets, AAMAZ and the KTH Multi-view football datasets. Our HMR framework significantly outperforms the other state-of-the-art approaches and achieves a better recognition rate of 91% and 89.6% over the AAMAZ and KTH multi-view football datasets, respectively.

Keywords: computer vision, human motion analysis, random forest, machine learning

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3194 Visual Thinking Routines: A Mixed Methods Approach Applied to Student Teachers at the American University in Dubai

Authors: Alain Gholam

Abstract:

Visual thinking routines are principles based on several theories, approaches, and strategies. Such routines promote thinking skills, call for collaboration and sharing of ideas, and above all, make thinking and learning visible. Visual thinking routines were implemented in the teaching methodology graduate course at the American University in Dubai. The study used mixed methods. It was guided by the following two research questions: 1). To what extent do visual thinking inspire learning in the classroom, and make time for students’ questions, contributions, and thinking? 2). How do visual thinking routines inspire learning in the classroom and make time for students’ questions, contributions, and thinking? Eight student teachers enrolled in the teaching methodology course at the American University in Dubai (Spring 2017) participated in the following study. First, they completed a survey that measured to what degree they believed visual thinking routines inspired learning in the classroom and made time for students’ questions, contributions, and thinking. In order to build on the results from the quantitative phase, the student teachers were next involved in a qualitative data collection phase, where they had to answer the question: How do visual thinking routines inspire learning in the classroom and make time for students’ questions, contributions, and thinking? Results revealed that the implementation of visual thinking routines in the classroom strongly inspire learning in the classroom and make time for students’ questions, contributions, and thinking. In addition, student teachers explained how visual thinking routines allow for organization, variety, thinking, and documentation. As with all original, new, and unique resources, visual thinking routines are not free of challenges. To make the most of this useful and valued resource, educators, need to comprehend, model and spread an awareness of the effective ways of using such routines in the classroom. It is crucial that such routines become part of the curriculum to allow for and document students’ questions, contributions, and thinking.

Keywords: classroom display, student engagement, thinking classroom, visual thinking routines

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3193 Ilizarov's External Fixator. A Bone Regeneration Method Little Used in Africa. Our Experience of 20 Years in Cameroon.

Authors: Ibrahima Farikou, Kolontchang Gatchou Alberic Lionel, Tsiagadgui Jean Gustave, Ngo Yamben Marie-Ange, Handy Eone Daniel

Abstract:

Introduction: It was in 1956 that Ilizarov pioneered the concept of osteogenesis in distraction by the device that bears his name to help produce bone and soft tissue regeneration and bone consolidation. This technique is not widely used in Africa where, however, its applications are numerous (loss of bone substances, congenital or acquired malformations). Our goal is to bring the indications of Ilizarov's device back to our practice conditions. Methods: Our study was conducted in 2 hospitals over a period of 20 years. For the retrospective phase, this study included all complete usable records of patients operated on in the Ilizarov external fixator department, and for the prospective phase, all patients operated on in the departments with complete usable records. Our sample was consecutive and not exhaustive. Data were analyzed by SPSS software version 23.0. Results: A total of 52 patients were reviewed. The average age of our patients was 14.7 years. The sex ratio was 1.6 in favor of men. The lower limb was the most affected (49), with a predominance of the tibia (62.4%). The average elongation was 6.4 cm. Traumatic acquired pathologies (delayed union, malunion) represented 60.6%. The mean time to union was seven months. Correction of the limb length discrepancy or filling of loss of bone substance was obtained in 75% of cases. Functionally, 80.8% of the patients treated had regained autonomy at the end of treatment, but in 17.3% of the patients, pain and limping persisted. Conclusion: This technique should be popularized in Africa because the benefit that would accrue to patients is invaluable and would be an attractive alternative to many amputations sometimes carried out in Africa by despair.

Keywords: ilizarov, external fixator, limb lengthening, bone regeneration, africa

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3192 A Hybrid Expert System for Generating Stock Trading Signals

Authors: Hosein Hamisheh Bahar, Mohammad Hossein Fazel Zarandi, Akbar Esfahanipour

Abstract:

In this paper, a hybrid expert system is developed by using fuzzy genetic network programming with reinforcement learning (GNP-RL). In this system, the frame-based structure of the system uses the trading rules extracted by GNP. These rules are extracted by using technical indices of the stock prices in the training time period. For developing this system, we applied fuzzy node transition and decision making in both processing and judgment nodes of GNP-RL. Consequently, using these method not only did increase the accuracy of node transition and decision making in GNP's nodes, but also extended the GNP's binary signals to ternary trading signals. In the other words, in our proposed Fuzzy GNP-RL model, a No Trade signal is added to conventional Buy or Sell signals. Finally, the obtained rules are used in a frame-based system implemented in Kappa-PC software. This developed trading system has been used to generate trading signals for ten companies listed in Tehran Stock Exchange (TSE). The simulation results in the testing time period shows that the developed system has more favorable performance in comparison with the Buy and Hold strategy.

Keywords: fuzzy genetic network programming, hybrid expert system, technical trading signal, Tehran stock exchange

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3191 Linguistic Features for Sentence Difficulty Prediction in Aspect-Based Sentiment Analysis

Authors: Adrian-Gabriel Chifu, Sebastien Fournier

Abstract:

One of the challenges of natural language understanding is to deal with the subjectivity of sentences, which may express opinions and emotions that add layers of complexity and nuance. Sentiment analysis is a field that aims to extract and analyze these subjective elements from text, and it can be applied at different levels of granularity, such as document, paragraph, sentence, or aspect. Aspect-based sentiment analysis is a well-studied topic with many available data sets and models. However, there is no clear definition of what makes a sentence difficult for aspect-based sentiment analysis. In this paper, we explore this question by conducting an experiment with three data sets: ”Laptops”, ”Restaurants”, and ”MTSC” (Multi-Target-dependent Sentiment Classification), and a merged version of these three datasets. We study the impact of domain diversity and syntactic diversity on difficulty. We use a combination of classifiers to identify the most difficult sentences and analyze their characteristics. We employ two ways of defining sentence difficulty. The first one is binary and labels a sentence as difficult if the classifiers fail to correctly predict the sentiment polarity. The second one is a six-level scale based on how many of the top five best-performing classifiers can correctly predict the sentiment polarity. We also define 9 linguistic features that, combined, aim at estimating the difficulty at sentence level.

Keywords: sentiment analysis, difficulty, classification, machine learning

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3190 Application of Single Tuned Passive Filters in Distribution Networks at the Point of Common Coupling

Authors: M. Almutairi, S. Hadjiloucas

Abstract:

The harmonic distortion of voltage is important in relation to power quality due to the interaction between the large diffusion of non-linear and time-varying single-phase and three-phase loads with power supply systems. However, harmonic distortion levels can be reduced by improving the design of polluting loads or by applying arrangements and adding filters. The application of passive filters is an effective solution that can be used to achieve harmonic mitigation mainly because filters offer high efficiency, simplicity, and are economical. Additionally, possible different frequency response characteristics can work to achieve certain required harmonic filtering targets. With these ideas in mind, the objective of this paper is to determine what size single tuned passive filters work in distribution networks best, in order to economically limit violations caused at a given point of common coupling (PCC). This article suggests that a single tuned passive filter could be employed in typical industrial power systems. Furthermore, constrained optimization can be used to find the optimal sizing of the passive filter in order to reduce both harmonic voltage and harmonic currents in the power system to an acceptable level, and, thus, improve the load power factor. The optimization technique works to minimize voltage total harmonic distortions (VTHD) and current total harmonic distortions (ITHD), where maintaining a given power factor at a specified range is desired. According to the IEEE Standard 519, both indices are viewed as constraints for the optimal passive filter design problem. The performance of this technique will be discussed using numerical examples taken from previous publications.

Keywords: harmonics, passive filter, power factor, power quality

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3189 Cumulus-Oocyte Complexes and Follicular Fluid Proteins of Pig during Folliculogenesis

Authors: Panomporn Wisuthseriwong, Hatairuk Tungkasen, Siyaporn Namsongsan, Chanikarn Srinark, Mayuva Youngsabanant-Areekijseree

Abstract:

The objective of the present study was to evaluate the morphology of porcine cumulus-oocyte complexes (pCOCs) and follicular fluid during follicular development. The samples were obtained from local slaughterhouses in Nakorn Pathom Province, Thailand. Pigs were classified as either in the follicular phase or luteal phase. Porcine follicles (n = 3,510) were categorized as small (1-3 mm in diameters; n=2,910), medium (4-6 mm in diameters; n=530) and large (7-8 mm in diameters; n=70). Then pCOCs and follicular fluid were collected. Finally, we found that the oocytes can be categorized into intact cumulus cells layer oocyte, multi-cumulus cells layer oocyte, partial cumulus cells layer oocyte, completely denuded oocyte and degenerated oocyte. They showed high percentage of intact and multi-cumulus cells layer oocytes from small follicles (54.68%) medium follicles (69.06%) and large follicles (68.57%), which have high potential to develop into matured oocytes in vitro. Protein composition of the follicular fluid was separated by SDS-PAGE technique. The result shows that the protein molecular weight in the small and medium follicles are 23, 50, 66, 75, 92, 100, 132, 163, 225 and >225 kDa. Meanwhile, protein molecular weight in large follicles are 12, 16, 23, 50, 66, 75, 92, 100, 132, 163, 225 and >225 kDa. All proteins play an important role in promotion and regulation on development, maturation of oocytes and regulation of ovulation. We conclude that the results of discovery can be used porcine secretion proteins for supplement in IVM/IVF technology. Acknowledgements: The project was funded by a grant from Silpakorn University Research and Development Institute (SURDI) and Faculty of Science, Silpakorn University, Thailand.

Keywords: porcine follicles, porcine oocyte, follicular fluid, SDS-PAGE

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3188 Regional Analysis of Freight Movement by Vehicle Classification

Authors: Katerina Koliou, Scott Parr, Evangelos Kaisar

Abstract:

The surface transportation of freight is particularly vulnerable to storm and hurricane disasters, while at the same time, it is the primary transportation mode for delivering medical supplies, fuel, water, and other essential goods. To better plan for commercial vehicles during an evacuation, it is necessary to understand how these vehicles travel during an evacuation and determine if this travel is different from the general public. The research investigation used Florida's statewide continuous-count station traffic volumes, where then compared between years, to identify locations where traffic was moving differently during the evacuation. The data was then used to identify days on which traffic was significantly different between years. While the literature on auto-based evacuations is extensive, the consideration of freight travel is lacking. To better plan for commercial vehicles during an evacuation, it is necessary to understand how these vehicles travel during an evacuation and determine if this travel is different from the general public. The goal of this research was to investigate the movement of vehicles by classification, with an emphasis on freight during two major evacuation events: hurricanes Irma (2017) and Michael (2018). The methodology of the research was divided into three phases: data collection and management, spatial analysis, and temporal comparisons. Data collection and management obtained continuous-co station data from the state of Florida for both 2017 and 2018 by vehicle classification. The data was then processed into a manageable format. The second phase used geographic information systems (GIS) to display where and when traffic varied across the state. The third and final phase was a quantitative investigation into which vehicle classifications were statistically different and on which dates statewide. This phase used a two-sample, two-tailed t-test to compare sensor volume by classification on similar days between years. Overall, increases in freight movement between years prevented a more precise paired analysis. This research sought to identify where and when different classes of vehicles were traveling leading up to hurricane landfall and post-storm reentry. Of the more significant findings, the research results showed that commercial-use vehicles may have underutilized rest areas during the evacuation, or perhaps these rest areas were closed. This may suggest that truckers are driving longer distances and possibly longer hours before hurricanes. Another significant finding of this research was that changes in traffic patterns for commercial-use vehicles occurred earlier and lasted longer than changes for personal-use vehicles. This finding suggests that commercial vehicles are perhaps evacuating in a fashion different from personal use vehicles. This paper may serve as the foundation for future research into commercial travel during evacuations and explore additional factors that may influence freight movements during evacuations.

Keywords: evacuation, freight, travel time, evacuation

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3187 Simultaneous Saccharification and Fermentation for D-Lactic Acid Production from Dried Distillers Grains with Solubles

Authors: Nurul Aqilah Mohd Zaini, Afroditi Chatzifragkou, Dimitris Charalampopoulos

Abstract:

D-Lactic acid production is gaining increasing attention due to the thermostable properties of its polymer, Polylactic Acid (PLA). In this study, D-lactic acid was produced in microbial cultures using Lactobacillus coryniformis subsp. torquens as D-lactic acid producer and hydrolysates of Dried Distillers Grains with Solubles (DDGS) as fermentation substrate. Prior to fermentation, DDGS was first alkaline pretreated with 5% (w/v) NaOH, for 15 minutes (121oC/ ~16 psi). This led to the generation of DDGS solid residues, rich in carbohydrates and especially cellulose (~52%). The carbohydrate-rich solids were then subjected to enzymatic hydrolysis with Accellerase® 1500. For Separate Hydrolysis and Fermentation (SHF), enzymatic hydrolysis was carried out at 50oC for 24 hours, followed by fermentation of D-lactic acid at 37oC in controlled pH 6. The obtained hydrolysate contained 24 g/l glucose, 5.4 g/l xylose and 0.6 g/l arabinose. In the case of Simultaneous Saccharification and Fermentation (SSF), hydrolysis and fermentation were conducted in a single step process at 37oC in pH 5. The enzymatic hydrolysis of DGGS pretreated solids took place mostly during lag phase of L. coryniformis fermentation, with only a small amount of glucose consumed during the first 6 h. When exponential phase was started, glucose generation reduced as the microorganism started to consume glucose for D-lactic acid production. Higher concentrations of D-lactic acid were produced when SSF approach was applied, with 28 g/l D-lactic acid after 24 h of fermentation (84.5% yield). In contrast, 21.2 g/l D-lactic acid were produced when SHF was used. The optical pu rity of D-lactic acid produced from both experiments was 99.9%. Besides, approximately 2 g/l acetic acid was also generated due to lactic acid degradation after glucose depletion in SHF. SSF was proved an efficient towards DDGS ulilisation and D-lactic acid production, by reducing the overall processing time, yielding sufficient D-lactic acid concentrations without the generation of fermentation by-products.

Keywords: DDGS, alkaline pretreatment, SSF, D-lactic acid

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3186 Precipitation Kinetics of Al-7%Mg Alloy Studied by DSC and XRD

Authors: M. Fatmi, T. Chihi, M. A. Ghebouli, B. Ghebouli

Abstract:

This work presents the experimental results of the differential scanning calorimetry (DSC), hardness measurements (Hv) and XRD analysis, for order to investigate the kinetics of precipitation phenomena in Al-7%wt. Mg alloy. In the XRD and DSC curves indicates the formation of the intermediate precipitation of β-(Al3Mg2) phase respectively. The activation energies associated with the processes have been determined according to the three models proposed by Kissinger, Ozawa, and Boswell. Consequently, the nucleation mechanism of the precipitates can be explained. These phases are confirmed by XRD analysis.

Keywords: discontinuous precipitation, hardening, Al–Mg alloys, mechanical and mechatronics engineering

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3185 Attempts for the Synthesis of Indol-Ring Fluorinated Tryptophan Derivatives to Enhance the Activity of Antimicrobial Peptides

Authors: Anita K. Kovacs, Peter Hegyes, Zsolt Bozso, Gabor Toth

Abstract:

Fluorination has been used extensively by the pharmaceutical industry as a strategy to improve the pharmacokinetics of drugs due to its effectiveness in increasing the potency of antimicrobial peptides (AMPs). Multiple-fluorinated indole-ring-containing tryptophan derivatives have the potential of having better antimicrobial activity than the widely used mono-fluorinated indole-ring containing tryptophan derivatives, but they are not available commercially. Therefore, our goal is to synthesize multiple-fluorinated indole-ring containing tryptophan derivatives to incorporate them into AMPs to enhance their antimicrobial activity. During our work, we are trying several methods (classical organic synthesis, enzymic synthesis, and solid phase peptide synthesis) for the synthesis of the said compounds, with mixed results. With classical organic synthesis (four different routes), we did not get the desired results. The reaction of serin with substituted indole in the presence of acetic anhydride led to racemic tryptophane; with the reaction of protected serin with indole in the presence of nickel complex was unsuccessful; the reaction of serin containing protected dipeptide with disuccinimidyl carbonate we achieved a tryptophane containing dipeptide, its chiral purity is being examined; the reaction of alcohol with substituted indole in the presence of copper complex was successful, but it was only a test reaction, we could not reproduce the same result with serine. The undergoing tryptophan-synthase method has shown some potential, but our work has not been finished yet. The successful synthesis of the desired multiple-fluorinated indole-ring-containing tryptophan will be followed by solid phase peptide synthesis in order to incorporate it into AMPs to enhance their antimicrobial activity. The successful completion of these phases will mean the possibility of manufacturing new, effective AMPs.

Keywords: halogenation, fluorination, tryptophan, enhancement of antimicrobial activity

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