Search results for: soft particle

Authors: Emily J. Morey, Kevin Galvin, Thomas Riley, R. Eddie Wilson

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The key challenges faced by integrating autonomous rail operations into the existing mainline railway environment have been identified through the understanding and framing of the problem space and stakeholder analysis. This was achieved through the completion of the first four steps of Soft Systems Methodology, where the problem space has been expressed via conceptual models. Having identified these challenges, we investigated one of them, namely capacity, via the use of models and simulation. This paper examines the approach used to move from the conceptual models to a simulation which can determine whether the integration of autonomous trains can plausibly increase capacity. Within this approach, we developed an architecture and converted logical models into physical resource models and associated design features which were used to build a simulator. From this simulator, we are able to analyse mixtures of legacy-autonomous operations and produce fundamental diagrams and trajectory plots to describe the dynamic behaviour of mixed mainline railway operations.

Keywords: autonomy, executable architecture, modelling and simulation, railway capacity

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Authors: Prakash Chand, Anurag Gaur, Ashavani Kumar

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In the present study, we have synthesized Cr and Fe doped zinc oxide (ZnO) nano-structures (Zn1-δCraFebO; where δ= a + b=20%, a = 5, 6, 8 & 10% and b=15, 14, 12 & 10%) via sol-gel method at different doping concentrations. The synthesized samples were characterized for structural properties by X-ray diffractometer and field emission scanning electron microscope and the optical properties were carried out through photoluminescence and UV-visible spectroscopy. The particle size calculated through field emission scanning electron microscope varies from 41 to 96 nm for the samples synthesized at different doping concentrations. The optical band gaps calculated through UV-visible spectroscopy are found to be decreasing from 3.27 to 3.02 eV as the doping concentration of Cr increases and Fe decreases.

Keywords: nano-structures, optical properties, sol-gel method, zinc oxide

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Authors: Margarita S. Tikhonova, Alireza Baniasad, Anton G. Kalmykov, Georgy A. Kalmykov, Ralf Littke

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There is a high complexity in the pore structure of organic-rich rocks caused by the combination of inter-particle porosity from inorganic mineral matter and ultrafine intra-particle porosity from both organic matter and clay minerals. Fluids are retained in that pore space, but there are major uncertainties in how and where the fluids are stored and to what extent they are accessible or trapped in 'closed' pores. A large degree of tortuosity may lead to fractionation of organic matter so that the lighter and flexible compounds would diffuse to the reservoir whereas more complicated compounds may be locked in place. Additionally, parts of hydrocarbons could be bound to solid organic matter –kerogen– and mineral matrix during expulsion and migration. Larger compounds can occupy thin channels so that clogging or oil and gas entrapment will occur. Sequential extraction of applying different solvents is a powerful tool to provide more information about the characteristics of trapped organic matter distribution. The Upper Jurassic – Lower Cretaceous Bazhenov shale is one of the most petroliferous source rock extended in West Siberia, Russia. Concerning the variable mineral composition, pore space distribution and thermal maturation, there are high uncertainties in distribution and composition of organic matter in this formation. In order to address this issue geological and geochemical properties of 30 samples including mineral composition (XRD and XRF), structure and texture (thin-section microscopy), organic matter contents, type and thermal maturity (Rock-Eval) as well as molecular composition (GC-FID and GC-MS) of different extracted materials during sequential extraction were considered. Sequential extraction was performed by a Soxhlet apparatus using different solvents, i.e., n-hexane, chloroform and ethanol-benzene (1:1 v:v) first on core plugs and later on pulverized materials. The results indicate that the studied samples are mainly composed of type II kerogen with TOC contents varied from 5 to 25%. The thermal maturity ranged from immature to late oil window. Whereas clay contents decreased with increasing maturity, the amount of silica increased in the studied samples. According to molecular geochemistry, stored hydrocarbons in open and closed pore space reveal different geochemical fingerprints. The results improve our understanding of hydrocarbon expulsion and migration in the organic-rich Bazhenov shale and therefore better estimation of hydrocarbon potential for this formation.

Keywords: Bazhenov formation, bitumen, molecular geochemistry, sequential extraction

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Authors: Eung Ryeol Seo, Hee Tae Lim, Eunsuk Bang, Soon Cheol Kweon, Jeoung-Kyo Jeoung, Ji-Hoon Choic

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The object of this study is to investigate the effect of pulsator on washing performance quantitatively for front-loading washer. The front-loading washer with pulsator shows washing performance improvement of 18% and the particle-based body simulation technique has been applied to figure out the relation between washing performance and mechanical forces exerted on textile during washing process. As a result, the mechanical forces, such as collision force and strain force, acting on the textile have turned out to be about twice numerically. The washing performance improvement due to additional pulsate system has been utilized for customers to save 50% of washing time.

Keywords: front-loading washer, mechanical force, fabric movement, pulsator, time-saving

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Authors: Yashvi Italiya

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Dysthymia (DD) is a much-overlooked soft mood disorder and mostly confused with other forms of chronic depression. This research paper gives a spotlight to the DD prevailing in men and women. It also focuses on one of the comorbidities of Dysthymia, i.e., Anxiety. The comorbidities, hurdles in diagnosis, the ubiquity of the disorder, and the relation of Anxiety and DD are briefly described. Gender was the main focus here because the researcher of this paper found it as a research gap while doing the literature review. The study was done through secondary data obtained primarily from a questionnaire having Alpha 0.891 reliability. T-test method of data analysis was used to test the hypotheses. The result shows that the researcher failed to accept alternative hypothesis 1 (M1 > M2), while the alternative hypothesis 2 (M1 > M2) was accepted. The ratio of DD in women (M1) is not higher than that of men (M2) (hypothesis 1). But, women are more anxious than men (hypothesis 2). It was found that comorbid Anxiety is more widespread in one gender. It further plays a significant role in mixing up the symptoms. It was concluded that the dividing line between Dysthymia and MDD is still unclear for an accurate diagnosis. There is an essential need for spreading knowledge concerning the differences between the symptoms of DD and MDD so that the actual disorder can be identified, and proper help can be received from/provided by professionals.

Keywords: anxiety, comorbidity, dysthymia, gender, MDD

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Authors: M. B. Tavakoli, R. Reiazi, M. M. Mohammadi, K. Jabbari

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From 2003, AD4/ACE experiment in CERN tried to investigate different aspects of antiproton as a new modality in particle therapy. Because of lack of reliable absolute dose measurements attempts to find out the radiobiological characteristics of antiproton have not reached to a reasonable result yet. From the other side, application of Geant4 in medical approaches is increased followed by Geant4-DNA project which focuses on using this code to predict radiation effects in the cellular scale. This way we can exploit Geant4-DNA results for antiproton. Unfortunately, previous studies showed there are serious problem in simulating an antiproton beam using Geant4. Since most of the problem was in the Bragg peak region which antiproton annihilates there, in this work we tried to understand if the problem came from the way in which Geant4 handles annihilation products especially pion particles. This way, we can predict the source of the dose discrepancies between Geant4 simulations and dose measurements done in CERN.

Keywords: Geant4, antiproton, annihilation, pion plus, pion minus

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Authors: Li Hung-Hui, Chen Chi-Chieh, Yang Zon-Yee

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This study aims to explore the impact energy absorption in the fragmented processes of rock samples during the split-Hopkinson-pressure-bar tests. Three kinds of rock samples including granite, marble and sandstone were tested. The impact energy absorptions were calculated according to the incident, reflected and transmitted strain wave histories measured by a oscilloscope. The degree of fragment rocks after tests was quantified by the box dimension of the fractal theory. The box dimension of rock fragments was obtained from the particle size distribution curve by the sieve analysis. The results can be concluded that: (1) the degree of rock fragments after tests can be well described by the value of box dimension; (2) with the impact energy absorption increasing, the degrees of rock fragments are varied from the very large fragments to very small fragments, and the corresponding box dimension varies from 2.9 to 1.2.

Keywords: SHPB test, energy absorption, rock fragments, impact loading, box dimension

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Authors: Sudhir Kumar, V. R. Sinha

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Background: The topical and systemic toxicity associated with present nonmelanoma skin cancer (NMSC) treatment therapy using 5-Fluorouracil (5-FU) make it necessary to develop a novel delivery system having lesser toxicity and better control over drug release. Solid lipid nanoparticles offer many advantages like: controlled and localized release of entrapped actives, nontoxicity, and better tolerance. Aim:-To investigate safety and efficacy of 5-FU loaded solid lipid nanoparticles as a topical delivery system for the treatment of nonmelanoma skin cancer. Method: Topical solid lipid nanoparticles of 5-FU were prepared using Compritol 888 ATO (Glyceryl behenate) as lipid component and pluronic F68 (Poloxamer 188), Tween 80 (Polysorbate 80), Tyloxapol (4-(1,1,3,3-Tetramethylbutyl) phenol polymer with formaldehyde and oxirane) as surfactants. The SLNs were prepared with emulsification method. Different formulation parameters viz. type and ratio of surfactant, ratio of lipid and ratio of surfactant:lipid were investigated on particle size and drug entrapment efficiency. Results: Characterization of SLNs like–Transmission Electron Microscopy (TEM), Differential Scannig calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), Particle size determination, Polydispersity index, Entrapment efficiency, Drug loading, ex vivo skin permeation and skin retention studies, skin irritation and histopathology studies were performed. TEM results showed that shape of SLNs was spherical with size range 200-500nm. Higher encapsulation efficiency was obtained for batches having higher concentration of surfactant and lipid. It was found maximum 64.3% for SLN-6 batch with size of 400.1±9.22 nm and PDI 0.221±0.031. Optimized SLN batches and marketed 5-FU cream were compared for flux across rat skin and skin drug retention. The lesser flux and higher skin retention was obtained for SLN formulation in comparison to topical 5-FU cream, which ensures less systemic toxicity and better control of drug release across skin. Chronic skin irritation studies lacks serious erythema or inflammation and histopathology studies showed no significant change in physiology of epidermal layers of rat skin. So, these studies suggest that the optimized SLN formulation is efficient then marketed cream and safer for long term NMSC treatment regimens. Conclusion: Topical and systemic toxicity associated with long-term use of 5-FU, in the treatment of NMSC, can be minimized with its controlled release with significant drug retention with minimal flux across skin. The study may provide a better alternate for effective NMSC treatment.

Keywords: 5-FU, topical formulation, solid lipid nanoparticles, non melanoma skin cancer

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Authors: Y. J. Song, Q. S. Xu, X. C. Wang, H. Wang, C. Q. Li

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The catalyst of copper oxide loaded on HZSM-5 was developed for nitrous oxide (N₂O) direct decomposition. The kinetic of nitrous oxide decomposition was studied for CuO/HZSM-5 catalyst prepared by incipient wetness impregnation method. The external and internal diffusion of catalytic reaction were considered in the investigation. Experiment results indicated that the external diffusion was basically eliminated when the reaction gas mixture gas hourly space velocity (GHSV) was higher than 9000h⁻¹ and the influence of the internal diffusion was negligible when the particle size of the catalyst CuO/HZSM-5 was small than 40-60 mesh. The experiment results showed that the kinetic of catalytic decomposition of N₂O was a first-order reaction and the activation energy and the pre-factor of the kinetic equation were 115.15kJ/mol and of 1.6×109, respectively.

Keywords: catalytic decomposition, CuO/HZSM-5, kinetic, nitrous oxide

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Authors: Idrees Khan, Zhang Baoliang

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Kaolin clay (KC) supported Zinc oxide (ZnO/KC) and ZnO nanoparticles (NPs) were prepared by a chemical reduction process and used for the photodegradation of methyl red (MR) as photocatalysts. Due to the interlayered porous structure of KC, we achieved a perfect association between ZnO NPs and KC. SEM image showed the irregular morphology of ZnO NPs, while ZnO/KC NCs were predominately round-shaped. Moreover, in both cases, NPs were present in dispersed and agglomerated forms with an average particle size way below 100 nm. The results acquired from photodegradation analyses showed that ZnO NPs and ZnO/KC NCs degraded about 82% and 99% of MR under UV light in a short irradiation time within 10 min. The recovered and re-recovered ZnO NPs and ZnO/KC NCs were also considerably photodegraded MR in an aqueous medium. The same NPs also exhibit promising bioactivities against two pathogenic bacteria, i.e., Citrobacter and Providencia. ZnO/KC NCs' antioxidant activity reached a reasonable 70% compared to the 88% activity of the standard ascorbic acid.

Keywords: nanoparticles, photocatalyst, photodegradation, zinc oxide, methyl red

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Authors: A. M. Nasr, W. R. Azzam, K. E. Ebeed

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For bored piles, careful cleaning must be used to reduce the amount of material trapped in the drilled hole; otherwise, the debris' presence might cause the soft toe effect, which would affect the axial resistance. There isn't much comprehensive research on bored piles with debris. In order to investigate the behavior of a single pile, a pile composite foundation, a two pile group, a three pile group and a four pile group investigation conducts, forty-eight numerical tests in which the debris is simulated using foam rubber.1m pile diameter and 10m length with spacing 3D and depth of foundation 1m used in this study. It is found that the existence of debris causes a reduction of bearing capacity by 64.58% and 33.23% for single pile and pile composite foundation, respectively, 23.27% and 24.24% for the number of defective piles / total number of pile =1/2 and 1 respectively for two group pile, 10.23%, 19.42% and 28.47% for the number of defective piles / total number of pile =1/3,2/3 and 1 respectively for three group pile and, this reduction increase with the increase in a number of defective piles / a total number of piles and 7.1%, 13.32%,19.02% and 26.36 for the number of defective piles / total number of pile =1/4,2/4,3/4 and 1 respectively for four group pile and decreases with an increase of number of pile duo to interaction effect.

Keywords: debris, Foundation, defective, interaction, board pile

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Authors: Tan G. K. Y., Chew M. S. J., Sajeev S., Vellasamy A.

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Injuries of the extensor hallucis longus (EHL) tendon are a rare phenomenon, with most occurring due to lacerations or penetrating injuries. Closed traumatic ruptures of the EHL are described as “Mallet injuries of the toe”. These can be classified as bony or soft mallet injuries depending on the presence or absence of a fracture at the insertion site of the EHL tendon in the distal phalanx. We present a case of a 33-year-old woman who presented with a hyperflexion injury to the left big toe with an inability to extend the big toe. Ultrasound showed a complete rupture of the EHL tendon with retraction proximal to the hallucal interphalangeal joint of the big toe. The patient was treated through transarticular pinning and repair using the Arthrex Mini Bio-Suture Tak with a 2-0 fibre wire. Six months postoperatively, the patient had symmetrical EHL power and full range of motion of the toe. The lessons to be drawn from this case report are that isolated hallux mallet injuries are rare and can be easily missed in the absence of penetrating wounds. Patients who have such injuries should be investigated early with the appropriate imaging techniques, such as ultrasound or MRI, and treated surgically.

Keywords: hallux mallet, extensor hallucis longus tendon, extensor hallucis longus

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Authors: Sherry Robinson, Hans Anton Stubberud

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Entrepreneurship can take many forms. Traditional entrepreneurs seek profits and growth for the businesses they start themselves. Intrapreneurs act entrepreneurially within a business they do not own. Social entrepreneurs have goals other than (but not excluding) profit and growth as they seek to solve social problems or protect the environment. This type of entrepreneur often focuses on the triple bottom line, which includes a concern for people and the planet as well as profit. Ecopreneurs in particular are driven by their desire to create and promote environmentally sustainable products and processes. All of these entrepreneurs need an entrepreneurial orientation in order to survive and thrive. The three most common elements of an entrepreneurial orientation are (1) creativity and innovation, (2) the willingness to take risks and (3) the proactiveness to put ideas into action. This study describes an interdisciplinary entrepreneurship course integrating topics regarding the triple bottom line with those relevant to an entrepreneurial orientation. The results show that students significantly increased their skill levels in many areas, including soft skills such as communicating and working in teams, as well as designing innovative products and taking calculated risk.

Keywords: creativity, entrepreneurship education, sustainability, triple bottom line

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Authors: S. A. Kondratyev, O. I. Ibragimova

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The authors discuss the collecting abilities of desorbable species (DS) of saturated fatty acids. The DS species of the reagent are understood as species capable of moving from the surface of the mineral particle to the bubble at the moment of the rupture of the interlayer of liquid separating these objects of interaction. DS species of carboxylic acids (molecules and ionic-molecular complexes) have the ability to spread over the surface of the bubble. The rate of their spreading at pH 7 and 10 over the water surface is determined. The collectibility criterion of saturated fatty acids is proposed. The values of forces exerted by the spreading DS species of reagents on liquid in the interlayer and the liquid flow rate from the interlayer are determined.

Keywords: criterion of action of physically adsorbed reagent, flotation, saturated fatty acids, surface pressure

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Authors: Shawnrece Campbell

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Emotional intelligence as an essential job skill is growing in popularity among human resource professionals and hiring managers. Companies value those who have high emotional intelligence because of their personal competences (self-awareness, self-regulation, motivation) and social competences (empathy, social skills). In implementing any training system to teach emotional intelligence, the best methodologies for acquiring and/or improving these competences should be taken into consideration. This study focuses on how students perceived the art of writing as a tool for self-improvement. During this session, participants will engage in a brief activity designed to help students develop emotional intelligence. As a part of the discussion, participants will learn the results of a junior-level literary seminar conducted to better understand students’ thoughts and views about the effectiveness of writing as a tool for emotional healing. An analysis of qualitative textual data is presented. The outcomes indicated that students found using writing as a tool for emotional intelligence development as highly effective. The findings also revealed that students have positive perceptions of using writing as a self-healing art that leads to increased emotional intelligence and believe that writing courses of this nature enhance students’ appreciation of the value of the liberal arts.

Keywords: emotional intelligence quotient, healing, soft skills, writing

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Authors: Robert Prucek, Aleš Panáček, Jan Filip, Libor Kvítek, Radek Zbořil

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The preparation of Cu nanoparticles (NPs) through the reduction of copper ions by sodium borohydride in the presence of sodium polyacrylate with a molecular weight of 1200 is reported. Cu NPs were synthesized at a concentration of copper salt equal to 2.5, 5, and 10 mM, and at a molar ratio of copper ions and monomeric unit of polyacrylate equal to 1:2. The as-prepared Cu NPs have diameters of about 2.5–3 nm for copper concentrations of 2.5 and 5 mM, and 6 nm for copper concentration of 10 mM. Depending on the copper salt concentration and concentration of additionally added polyacrylate to Cu particle dispersion, primarily formed NPs grow through the process of aggregation and/or coalescence into clusters and/or particles with a diameter between 20–100 nm. The amount of additionally added sodium polyacrylate influences the stability of Cu particles against air oxidation. The catalytic efficiency of the prepared Cu particles for the reduction of 4-nitrophenol is discussed.

Keywords: copper, nanoparticles, sodium polyacrylate, catalyst, 4-nitrophenol

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Authors: T. M. Ismail, M. A. El-Salam

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A mathematical model study was carried out to investigate gasification of biomass fuels using high-temperature air and steam as a gasifying agent using high-temperature air up to 1000°C. In this study, a 2D computational fluid dynamics model was developed to study the gasification process in an updraft gasifier, considering drying, pyrolysis, combustion, and gasification reactions. The gas and solid phases were resolved using a Euler−Euler multiphase approach, with exchange terms for the momentum, mass, and energy. The standard k−ε turbulence model was used in the gas phase, and the particle phase was modeled using the kinetic theory of granular flow. The results show that the present model giving a promising way in its capability and sensitivity for the parameter effects that influence the gasification process.

Keywords: computational fluid dynamics, gasification, biomass fuel, fixed bed gasifier

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Authors: Ghada Hasabo, Mahmoud Saber Elbasiouny, Mervat Abdelsalam, Sherin Ghaleb, Niveen Eldessouky

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In the near future, nanotechnology is envisaged for large scale use. Hence health and safety issues of nanoparticles should be promptly addressed. In the present study the acute hepatoxicity assessment due to high single oral dose of nano iron and micro iron particles were studied. The normal daily activities, biochemical alterations, blood coagulation, histopathological changes in Wister rats were the aspect of the toxicological assessment.This work found that significant alterations in biochemical enzymes (serum iron level, liver enzymes, albumin, and bilirubin levels), blood coagulation (PT, PC, INR), and histopathological changes occurred more prominently in the nano iron particle treated group.

Keywords: nanobiotechnology, nanosystems, nanomaterials, nanotechnology

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Authors: A. Mohammadi, S. Asghari, M. Aien, M. Rashidinejad

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After emergent of alternative current networks and their popularity, asynchronous motors became more widespread than other kinds of industrial motors. In order to control and run these motors efficiently, an accurate estimation of motor parameters is needed. There are different methods to obtain these parameters such as rotor locked test, no load test, DC test, analytical methods, and so on. The most common drawback of these methods is their inaccuracy in estimation of some motor parameters. In order to remove this concern, a novel method for parameter estimation of induction motors using particle swarm optimization (PSO) algorithm is proposed. In the proposed method, transient state of motor is used for parameter estimation. Comparison of the simulation results purtuined to the PSO algorithm with other available methods justifies the effectiveness of the proposed method.

Keywords: induction motor, motor parameter estimation, PSO algorithm, analytical method

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Authors: Qimin Shi, Yi Sun, Constantinus Politis, Shoufeng Yang

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In-situ preparation of particle-reinforced aluminium matrix composites (PRAMCs) by laser powder bed fusion (LPBF) additive manufacturing is a promising strategy to strengthen traditional Al-based alloys. The laser-driven thermite reaction can be a practical mechanism to in-situ synthesize PRAMCs. However, introducing oxygen elements through adding Fe₂O₃ makes the powder mixture highly sensitive to form porosity and Al₂O₃ film during LPBF, bringing challenges to producing dense Al-based materials. Therefore, this work develops a processing strategy combined with consecutive high-energy laser melting scanning and low-energy laser remelting scanning to prepare PRAMCs from a Fe₂O₃/AlSi12 powder mixture. The powder mixture consists of 5 wt% Fe₂O₃ and the remainder AlSi12 powder. The addition of 5 wt% Fe₂O₃ aims to achieve balanced strength and ductility. A high relative density (98.2 ± 0.55 %) was successfully obtained by optimizing laser melting (Emelting) and laser remelting surface energy density (Eremelting) to Emelting = 35 J/mm² and Eremelting = 5 J/mm². Results further reveal the necessity of increasing Emelting, to improve metal liquid’s spreading/wetting by breaking up the Al₂O₃ films surrounding the molten pools; however, the high-energy laser melting produced much porosity, including H₂₋, O₂₋ and keyhole-induced pores. The subsequent low-energy laser remelting could close the resulting internal pores, backfill open gaps and smoothen solidified surfaces. As a result, the material was densified by repeating laser melting and laser remelting layer by layer. Although with two-times laser scanning, the microstructure still shows fine cellular Si networks with Al grains inside (grain size of about 370 nm) and in-situ nano-precipitates (Al₂O₃, Si, and Al-Fe(-Si) intermetallics). Finally, the fine microstructure, nano-structured dispersion strengthening, and high-level densification strengthened the in-situ PRAMCs, reaching yield strength of 426 ± 4 MPa and tensile strength of 473 ± 6 MPa. Furthermore, the results can expect to provide valuable information to process other powder mixtures with severe porosity/oxide-film formation potential, considering the evidenced contribution of laser melting/remelting strategy to densify material and obtain good mechanical properties during LPBF.

Keywords: densification, laser powder bed fusion, metal matrix composites, microstructures, mechanical properties

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Authors: K. R. Phaneesh, Anirudh Bhat, G. Mukherjee, K. T. Kashyap

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Extensive Monte Carlo Potts model simulations were performed on 2D square lattice to investigate the effects of simulated higher temperatures effects on grain growth kinetics. A range of simulation temperatures (KTs) were applied on a matrix of size 10002 with Q-state 64, dispersed with a wide range of second phase particles, ranging from 0.001 to 0.1, and then run to 100,000 Monte Carlo steps. The average grain size, the largest grain size and the grain growth exponent were evaluated for all particle fractions and simulated temperatures. After evaluating several growth parameters, the critical temperature for a square lattice, with eight nearest neighbors, was found to be KTs = 0.4.

Keywords: average grain size, critical temperature, grain growth exponent, Monte Carlo steps

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Authors: Yaseen Elhebshi, Abdulkareem Hamid, Nureddin Bin Issa, Xiaonong Chen

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A convenient method of preparing ultrafine polystyrene latex nano-particles with amino groups on the surface is developed. Polystyrene latexes in the size range 50–400 nm were prepared via emulsion polymerization, using sodium dodecyl sulfate (SDS) as surfactant. Polystyrene with amino groups on the surface will be fine to use as organic filler to modify rubber. Transmission electron microscopy (TEM) was used to observe the morphology of silicon dioxide and functionalized polystyrene nano-particles. The nature of bonding between the polymer and the reactive groups on the filler surfaces was analyzed using Fourier transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) was employed to examine the filler surface.

Keywords: reactive filler, emulsion polymerization, particle size, polystyrene nanoparticles

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Authors: Vinti Davar

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Introduction: Childhood overweight increases the risk for certain medical and psychological conditions. Millions of school-age children worldwide are affected by serious yet easily treatable and preventable illnesses that inhibit their ability to learn. Healthier children stay in school longer, attend more regularly, learn more and become healthier and more productive adults. Schools are an important setting for nutrition education because one can reach most children, teachers and parents. These years offer a key window for shaping their lifetime habits, which have an impact on their health throughout life. Against this background, an attempt was made to impart nutrition education to school children in Haryana state of India to promote healthy food choices and assess the effectiveness of this program. Methodology: This study was completed in two phases. During the first phase, pre-intervention anthropometric and dietary survey was conducted; the teaching materials for nutrition intervention program were developed and tested; and the questionnaire was validated. In the second phase, an intervention was implemented in two schools of Kurukshetra, Haryana for six months by personal visits once a week. A total of 350 children in the age group of 6-12 years were selected. Out of these, 279 children, 153 boys and 126 girls completed the study. The subjects were divided into four groups namely: underweight, normal, overweight and obese based on body mass index-for-age categories. A power point colorful presentation to improve the quality of tiffin, snacks and meals emphasizing inclusion of all food groups especially vegetables every day and fruits at least 3-4 days per week was used. An extra 20 minutes of aerobic exercise daily was likewise organized and a healthy school environment created. Provision of clean drinking water by school authorities was ensured. Selling of soft drinks and energy-dense snacks in the school canteen as well as advertisements about soft drink and snacks on the school walls were banned. Post intervention, anthropometric indices and food selections were reassessed. Results: The results of this study reiterate the critical role of nutrition education and promotion in improving the healthier food choices by school children. It was observed that normal, overweight and obese children participating in nutrition education intervention program significantly (p≤0.05) increased their daily seasonal fruit and vegetable consumption. Fat and oil consumption was significantly reduced by overweight and obese subjects. Fast food intake was controlled by obese children. The nutrition knowledge of school children significantly improved (p≤0.05) from pre to post intervention. A highly significant increase (p≤0.00) was noted in the nutrition attitude score after intervention in all four groups. Conclusion: This study has shown that a well-planned nutrition education program could improve nutrition knowledge and promote positive changes in healthy food choices. A nutrition program inculcates wholesome eating and active life style habits in children and adolescents that could not only prevent them from chronic diseases and early death but also reduce healthcare cost and enhance the quality of life of citizens and thereby nations.

Keywords: children, eating habits healthy food, obesity, school going, fast foods

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Authors: Miroslav Mrlik, Marketa Ilcikova, Martin Cvek, Josef Osicka, Michal Sedlacik, Vladimir Pavlinek, Jaroslav Mosnacek

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Magnetorheological elastomers (MREs) are a unique type of materials consisting of two components, magnetic filler, and elastomeric matrix. Their properties can be tailored upon application of an external magnetic field strength. In this case, the change of the viscoelastic properties (viscoelastic moduli, complex viscosity) are influenced by two crucial factors. The first one is magnetic performance of the particles and the second one is off-state stiffness of the elastomeric matrix. The former factor strongly depends on the intended applications; however general rule is that higher magnetic performance of the particles provides higher MR performance of the MRE. Since magnetic particles possess low stability properties against temperature and acidic environment, several methods how to improve these drawbacks have been developed. In the most cases, the preparation of the core-shell structures was employed as a suitable method for preservation of the magnetic particles against thermal and chemical oxidations. However, if the shell material is not single-layer substance, but polymer material, the magnetic performance is significantly suppressed, due to the in situ polymerization technique, when it is very difficult to control the polymerization rate and the polymer shell is too thick. The second factor is the off-state stiffness of the elastomeric matrix. Since the MR effectivity is calculated as the relative value of the elastic modulus upon magnetic field application divided by elastic modulus in the absence of the external field, also the tuneability of the cross-linking reaction is highly desired. Therefore, this study is focused on the controllable modification of magnetic particles using a novel monomeric system based on 2-(1H-pyrrol-1-yl)ethyl methacrylate. In this case, the short polymer chains of different chain lengths and low polydispersity index will be prepared, and thus tailorable stability properties can be achieved. Since the relatively thin polymer chains will be grafted on the surface of magnetic particles, their magnetic performance will be affected only slightly. Furthermore, also the cross-linking density will be affected, due to the presence of the short polymer chains. From the application point of view, such MREs can be utilized for, magneto-resistors, piezoresistors or pressure sensors especially, when the conducting shell on the magnetic particles will be created. Therefore, the selection of the pyrrole-based monomer is very crucial and controllably thin layer of conducting polymer can be prepared. Finally, such composite particle consisting of magnetic core and conducting shell dispersed in elastomeric matrix can find also the utilization in shielding application of electromagnetic waves.

Keywords: atom transfer radical polymerization, core-shell, particle modification, electromagnetic waves shielding

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Authors: Asım Egitmen, Aysen Demir, Burcu Darendeli, Fatma Ulusal, Bilgehan Güzel

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Synthesizing supercritical carbon dioxide (scCO₂) soluble precursors would be helpful for many processes of material syntheses based on scCO₂. Ligand (amphi-(1Z, 2Z)-N-(2-fluoro-3-(trifluoromethyl) phenyl)-N'-hydroxy-2-(hydroxyimino) were synthesized from chloro glyoxime and flourus aniline and Pd(II) complex (precursor) prepared. For scCO₂ deposition method, organometallic precursor was dissolved in scCO₂ and impregnated onto the SBA-15 at 90 °C and 3000 psi. Then the organometallic precursor was reduced with H₂ in the CO₂ mixture (150 psi H₂ + 2850 psi CO₂). Pd deposited support material was characterized by ICP-OES, XRD, FE-SEM, TEM and EDX analyses. The Pd loading of the prepared catalyst, measured by ICP-OES showed a value of about 1.64% mol/g Pd of catalyst. Average particle size was found 5.3 nm. The catalytic activity of prepared catalyst was investigated over Suzuki-Miyaura C-C coupling reaction in different solvent with K₂CO₃ at 50 ^oC. The conversion ratio was determined by gas chromatography.

Keywords: nanoparticle, nanotube, oximes, precursor, supercritical CO2

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Authors: Kyoungjin Kim

Abstract:

Nanoscale thermites such as the composite mixture of nano-sized aluminum and molybdenum trioxide powders possess several technical advantages such as much higher reaction rate and shorter ignition delay, when compared to the conventional energetic formulations made of micron-sized metal and oxidizer particles. In this study, the self-propagation of combustion wave in compacted pellets of nanoscale thermite composites is modeled and computationally investigated by utilizing the activation energy reduction of aluminum particles due to nanoscale particle sizes. The present computational model predicts the speed of combustion wave propagation which is good agreement with the corresponding experiments of thermite reaction. Also, several characteristics of thermite reaction in nanoscale composites are discussed including the ignition delay and combustion wave structures.

Keywords: nanoparticles, thermite reaction, combustion wave, numerical modeling

Procedia PDF Downloads 376

Authors: Svilen Dimitrov, Manthan Pancholi, Norbert Schmitz, Didier Stricker

Abstract:

This paper presents the end-to-end development of a wearable motion sensing harness consisting of computational unit and four inertial measurement units to control three smartphone therapeutic games for children. The inertial data is processed in real time to obtain lower body motion information like knee raises, feet taps and squads. By providing a Wi-Fi connection interface the sensor harness acts wireless remote control for smartphone applications. By performing various lower body movements the users provoke corresponding game state changes. In contrary to the current similar offers, like Nintendo Wii Remote, Xbox Kinect and Playstation Move, this product, consisting of the sensor harness and the applications on top of it, are fully wearable, which means they do not rely on the user to be bound to concrete soft- or hardwareequipped space.

Keywords: wearable harness, inertial measurement units, smartphone therapeutic games, motion tracking, lower-body activity monitoring

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Authors: Tarek M. Alguhane, Ayman H. Khalil, Nour M. Fayed, Ayman M. Ismail

Abstract:

An existing RC building in Madinah is seismically evaluated with and without infill wall. Four model systems have been considered i. e. model I (no infill), model IIA (strut infill-update from field test), model IIB (strut infill- ASCE/SEI 41) and model IIC (strut infill-Soft storey-ASCE/SEI 41). Three dimensional pushover analyses have been carried out using SAP 2000 software incorporating inelastic material behavior for concrete, steel and infill walls. Infill wall has been modeled as equivalent strut according to suggested equation matching field test measurements and to the ASCE/SEI 41 equation. The effect of building modeling on the performance point as well as capacity and demand spectra due to EQ design spectrum function in Madinah area has been investigated. The response modification factor (R) for the 5 story RC building is evaluated from capacity and demand spectra (ATC-40) for the studied models. The results are summarized and discussed.

Keywords: infill wall, pushover analysis, response modification factor, seismic assessment

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Authors: Julia Reinold, Inge Hooijen, Christoph Meng, Melissa Siegel

Abstract:

This paper investigates whether or not students intend to stay in the Euregio Meuse-Rhine (EMR) after graduation taking into account the role of hard and soft locational factors, social factors as well as demographic aspects in shaping their mobility preferences. Since graduates are considered a convenient source of human capital in today’s knowledge based economy, it is crucial to understand what drives their mobility intentions in order to retain larger numbers of graduates. This is particularly true for peripheral regions, which need to compete with assumed more attractive economic centres. This paper adds a euregional perspective to the existing literature on graduate migration. Using survey data from 2015 from five higher education institutions in the EMR, this paper finds that mobility intentions are determined by students’ perceptions of the quality of life, openness and career opportunities in the euroregion. In addition, distance to the partner and other social ties such as family and friends influence migration intentions.

Keywords: Euroregion, graduate migration, highly skilled migration, human capital

Procedia PDF Downloads 271

Authors: S. M. Giripunje, Mohit Kumar

Abstract:

Acoustic energy that exists in our everyday life and environment have been overlooked as a green energy that can be extracted, generated, and consumed without any significant negative impact to the environment. The harvested energy can be used to enable new technology like wireless sensor networks. Technological developments in the realization of truly autonomous MEMS devices and energy storage systems have made acoustic energy harvesting (AEH) an increasingly viable technology. AEH is the process of converting high and continuous acoustic waves from the environment into electrical energy by using an acoustic transducer or resonator. AEH is not popular as other types of energy harvesting methods since sound waves have lower energy density and such energy can only be harvested in very noisy environment. However, the energy requirements for certain applications are also correspondingly low and also there is a necessity to observe the noise to reduce noise pollution. So the ability to reclaim acoustic energy and store it in a usable electrical form enables a novel means of supplying power to relatively low power devices. A quarter-wavelength straight-tube acoustic resonator as an acoustic energy harvester is introduced with polyvinylidene fluoride (PVDF) and PVDF doped with ZnO nanoparticles, piezoelectric cantilever beams placed inside the resonator. When the resonator is excited by an incident acoustic wave at its first acoustic eigen frequency, an amplified acoustic resonant standing wave is developed inside the resonator. The acoustic pressure gradient of the amplified standing wave then drives the vibration motion of the PVDF piezoelectric beams, generating electricity due to the direct piezoelectric effect. In order to maximize the amount of the harvested energy, each PVDF and PVDF-ZnO piezoelectric beam has been designed to have the same structural eigen frequency as the acoustic eigen frequency of the resonator. With a single PVDF beam placed inside the resonator, the harvested voltage and power become the maximum near the resonator tube open inlet where the largest acoustic pressure gradient vibrates the PVDF beam. As the beam is moved to the resonator tube closed end, the voltage and power gradually decrease due to the decreased acoustic pressure gradient. Multiple piezoelectric beams PVDF and PVDF-ZnO have been placed inside the resonator with two different configurations: the aligned and zigzag configurations. With the zigzag configuration which has the more open path for acoustic air particle motions, the significant increases in the harvested voltage and power have been observed. Due to the interruption of acoustic air particle motion caused by the beams, it is found that placing PVDF beams near the closed tube end is not beneficial. The total output voltage of the piezoelectric beams increases linearly as the incident sound pressure increases. This study therefore reveals that the proposed technique used to harvest sound wave energy has great potential of converting free energy into useful energy.

Keywords: acoustic energy, acoustic resonator, energy harvester, eigenfrequency, polyvinylidene fluoride (PVDF)

Procedia PDF Downloads 373