Search results for: molecular and supramolecular structure
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9283

Search results for: molecular and supramolecular structure

4963 Design and Optimisation of 2-Oxoglutarate Dioxygenase Expression in Escherichia coli Strains for Production of Bioethylene from Crude Glycerol

Authors: Idan Chiyanzu, Maruping Mangena

Abstract:

Crude glycerol, a major by-product from the transesterification of triacylglycerides with alcohol to biodiesel, is known to have a broad range of applications. For example, its bioconversion can afford a wide range of chemicals including alcohols, organic acids, hydrogen, solvents and intermediate compounds. In bacteria, the 2-oxoglutarate dioxygenase (2-OGD) enzymes are widely found among the Pseudomonas syringae species and have been recognized with an emerging importance in ethylene formation. However, the use of optimized enzyme function in recombinant systems for crude glycerol conversion to ethylene is still not been reported. The present study investigated the production of ethylene from crude glycerol using engineered E. coli MG1655 and JM109 strains. Ethylene production with an optimized expression system for 2-OGD in E. coli using a codon optimized construct of the ethylene-forming gene was studied. The codon-optimization resulted in a 20-fold increase of protein production and thus an enhanced production of the ethylene gas. For a reliable bioreactor performance, the effect of temperature, fermentation time, pH, substrate concentration, the concentration of methanol, concentration of potassium hydroxide and media supplements on ethylene yield was investigated. The results demonstrate that the recombinant enzyme can be used for future studies to exploit the conversion of low-priced crude glycerol into advanced value products like light olefins, and tools including recombineering techniques for DNA, molecular biology, and bioengineering can be used to allowing unlimited the production of ethylene directly from the fermentation of crude glycerol. It can be concluded that recombinant E.coli production systems represent significantly secure, renewable and environmentally safe alternative to thermochemical approach to ethylene production.

Keywords: crude glycerol, bioethylene, recombinant E. coli, optimization

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4962 Solvent-Aided Dispersion of Tannic Acid to Enhance Flame Retardancy of Epoxy

Authors: Matthew Korey, Jeffrey Youngblood, John Howarter

Abstract:

Background and Significance: Tannic acid (TA) is a bio-based high molecular weight organic, aromatic molecule that has been found to increase thermal stability and flame retardancy of many polymer matrices when used as an additive. Although it is biologically sourced, TA is a pollutant in industrial wastewater streams, and there is a desire to find applications in which to downcycle this molecule after extraction from these streams. Additionally, epoxy thermosets have revolutionized many industries, but are too flammable to be used in many applications without additives which augment their flame retardancy (FR). Many flame retardants used in epoxy thermosets are synthesized from petroleum-based monomers leading to significant environmental impacts on the industrial scale. Many of these compounds also have significant impacts on human health. Various bio-based modifiers have been developed to improve the FR of the epoxy resin; however, increasing FR of the system without tradeoffs with other properties has proven challenging, especially for TA. Methodologies: In this work, TA was incorporated into the thermoset by use of solvent-exchange using methyl ethyl ketone, a co-solvent for TA, and epoxy resin. Samples were then characterized optically (UV-vis spectroscopy and optical microscopy), thermally (thermogravimetric analysis and differential scanning calorimetry), and for their flame retardancy (mass loss calorimetry). Major Findings: Compared to control samples, all samples were found to have increased thermal stability. Further, the addition of tannic acid to the polymer matrix by the use of solvent greatly increased the compatibility of the additive in epoxy thermosets. By using solvent-exchange, the highest loading level of TA found in literature was achieved in this work (40 wt%). Conclusions: The use of solvent-exchange shows promises for circumventing the limitations of TA in epoxy.

Keywords: sustainable, flame retardant, epoxy, tannic acid

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4961 Examining the Importance of the Structure Based on Grid Computing Service and Virtual Organizations

Authors: Sajjad Baghernezhad, Saeideh Baghernezhad

Abstract:

Vast changes and developments achieved in information technology field in recent decades have made the review of different issues such as organizational structures unavoidable. Applying informative technologies such as internet and also vast use of computer and related networks have led to new organizational formations with a nature completely different from the traditional, great and bureaucratic ones; some common specifications of such organizations are transfer of the affairs out of the organization, benefiting from informative and communicative networks and centered-science workers. Such communicative necessities have led to network sciences development including grid computing. First, the grid computing was only to relate some sites for short – time and use their sources simultaneously, but now it has gone beyond such idea. In this article, the grid computing technology was examined, and at the same time, virtual organization concept was discussed.

Keywords: grid computing, virtual organizations, software engineering, organization

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4960 Direct Design of Steel Bridge Using Nonlinear Inelastic Analysis

Authors: Boo-Sung Koh, Seung-Eock Kim

Abstract:

In this paper, a direct design using a nonlinear inelastic analysis is suggested. Also, this paper compares the load carrying capacity obtained by a nonlinear inelastic analysis with experiment results to verify the accuracy of the results. The allowable stress design results of a railroad through a plate girder bridge and the safety factor of the nonlinear inelastic analysis were compared to examine the safety performance. As a result, the load safety factor for the nonlinear inelastic analysis was twice as high as the required safety factor under the allowable stress design standard specified in the civil engineering structure design standards for urban magnetic levitation railways, which further verified the advantages of the proposed direct design method.

Keywords: direct design, nonlinear inelastic analysis, residual stress, initial geometric imperfection

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4959 Thinking Historiographically in the 21st Century: The Case of Spanish Musicology, a History of Music without History

Authors: Carmen Noheda

Abstract:

This text provides a reflection on the way of thinking about the study of the history of music by examining the production of historiography in Spain at the turn of the century. Based on concepts developed by the historical theorist Jörn Rüsen, the article focuses on the following aspects: the theoretical artifacts that structure the interpretation of the limits of writing the history of music, the narrative patterns used to give meaning to the discourse of history, and the orientation context that functions as a source of criteria of significance for both interpretation and representation. This analysis intends to show that historical music theory is not only a means to abstractly explore the complex questions connected to the production of historical knowledge, but also a tool for obtaining concrete images about the intellectual practice of professional musicologists. Writing about the historiography of contemporary Spanish music is a task that requires both a knowledge of the history that is being written and investigated, as well as a familiarity with current theoretical trends and methodologies that allow for the recognition and definition of the different tendencies that have arisen in recent decades. With the objective of carrying out these premises, this project takes as its point of departure the 'immediate historiography' in relation to Spanish music at the beginning of the 21st century. The hesitation that Spanish musicology has shown in opening itself to new anthropological and sociological approaches, along with its rigidity in the face of the multiple shifts in dynamic forms of thinking about history, have produced a standstill whose consequences can be seen in the delayed reception of the historiographical revolutions that have emerged in the last century. Methodologically, this essay is underpinned by Rüsen’s notion of the disciplinary matrix, which is an important contribution to the understanding of historiography. Combined with his parallel conception of differing paradigms of historiography, it is useful for analyzing the present-day forms of thinking about the history of music. Following these theories, the article will in the first place address the characteristics and identification of present historiographical currents in Spanish musicology to thereby carry out an analysis based on the theories of Rüsen. Finally, it will establish some considerations for the future of musical historiography, whose atrophy has not only fostered the maintenance of an ingrained positivist tradition, but has also implied, in the case of Spain, an absence of methodological schools and an insufficient participation in international theoretical debates. An update of fundamental concepts has become necessary in order to understand that thinking historically about music demands that we remember that subjects are always linked by reciprocal interdependencies that structure and define what it is possible to create. In this sense, the fundamental aim of this research departs from the recognition that the history of music is embedded in the conditions that make it conceivable, communicable and comprehensible within a society.

Keywords: historiography, Jörn Rüssen, Spanish musicology, theory of history of music

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4958 Changes in Vocational Teacher Training in Hungary: Challenges and Possibilities

Authors: Anetta Bacsa-Bán

Abstract:

The training of vocational education teachers in Hungary was a special training system before the Bologna system, but under the influence of the Bologna system, the structure and content of the training changed significantly. The training of vocational teachers, including engineering teachers and vocational trainers, is considerably different when compared to the training of public education teachers. This study aims to present these differences and peculiarities, problems and issues of the training as well as to outline the possibilities of further development. During the study, the following methods were implemented: empirical research among students and graduates of vocational teacher training, as well as analysis of the relevant literature. The study summarizes the research and theoretical results related to vocational education and training (VET) teacher training over the past 15 years, with the aim of developing the training and mapping new directions in the field.

Keywords: vocational teacher, technical instructors, technical vocational instructors, theoretical aspects

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4957 Energy Management of Hybrid Energy Source Composed of a Fuel Cell and Supercapacitor for an Electric Vehicle

Authors: Mejri Achref

Abstract:

This paper proposes an energy management strategy for an electrical hybrid vehicle which is composed of a Proton Exchange Membrane (PEM) fuel cell and a supercapacitor storage device. In this paper, the mathematical model for the proposed power train, comprising the PEM Fuel Cell, supercapacitor, boost converter, inverter, and vehicular structure, was modeled in MATLAB/Simulink. The proposed algorithm is evaluated for the Highway Fuel Economy Test (HWFET) driving cycle. The obtained results demonstrate the effectiveness of the proposed energy management strategy in reduction of hydrogen consumption.

Keywords: proton exchange membrane fuel cell, hybrid vehicle, hydrogen consumption, energy management strategy

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4956 Photocatalytic Conversion of Water/Methanol Mixture into Hydrogen Using Cerium/Iron Oxides Based Structures

Authors: Wael A. Aboutaleb, Ahmed M. A. El Naggar, Heba M. Gobara

Abstract:

This research work reports the photocatalytic production of hydrogen from water-methanol mixture using three different 15% ceria/iron oxide catalysts. The catalysts were prepared by physical mixing, precipitation, and ultrasonication methods and labeled as catalysts A-C. The structural and texture properties of the obtained catalysts were confirmed by X-ray diffraction (XRD), BET-surface area analysis and transmission electron microscopy (TEM). The photocatalytic activity of the three catalysts towards hydrogen generation was then tested. Promising hydrogen productivity was obtained by the three catalysts however different gases compositions were obtained by each type of catalyst. Specifically, catalyst A had produced hydrogen mixed with CO₂ while the composite structure (catalyst B) had generated only pure H₂. In the case of catalyst C, syngas made of H₂ and CO was revealed, as a novel product, for the first time, in such process.

Keywords: hydrogen production, water splitting, photocatalysts, clean energy

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4955 US-India Strategic Bargaining and Power Balancing in South Asia

Authors: Anila Syed, Manzoor Ahmad

Abstract:

The relationship between United States and India has transformed from estrangement to wider engagement since 2004. With the convergence of interests and shared values both the US and India came close towards each other and evolved strategic partnership through civil nuclear cooperation. This paper analyze the cost and benefit of strategic partnership with India for US, the impact of India’s emergence as regional power on South Asian balance of power and its impact on Pak-US relationship. It also focuses on security structure of the region and challenges for the US to maintain strategic partnership with two rival states (India and Pakistan). The work also gives some recommendations for balancing power in the region in order to ensure durable peace not only between India and Pakistan but also in south Asia.

Keywords: US-India strategic partnership, civil-nuclear cooperation, balance of power, impacts on Pak-US relationship

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4954 Optimization of Fenton Process for the Treatment of Young Municipal Leachate

Authors: Bouchra Wassate, Younes Karhat, Khadija El Falaki

Abstract:

Leachate is a source of surface water and groundwater contamination if it has not been pretreated. Indeed, due to its complex structure and its pollution load make its treatment extremely difficult to achieve the standard limits required. The objective of this work is to show the interest of advanced oxidation processes on leachate treatment of urban waste containing high concentrations of organic pollutants. The efficiency of Fenton (Fe2+ +H2O2 + H+) reagent for young leachate recovered from collection trucks household waste in the city of Casablanca, Morocco, was evaluated with the objectives of chemical oxygen demand (COD) and discoloration reductions. The optimization of certain physicochemical parameters (initial pH value, reaction time, and [Fe2+], [H2O2]/ [Fe2+] ratio) has yielded good results in terms of reduction of COD and discoloration of the leachate.

Keywords: COD removal, color removal, Fenton process, oxidation process, leachate

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4953 A Location Routing Model for the Logistic System in the Mining Collection Centers of the Northern Region of Boyacá-Colombia

Authors: Erika Ruíz, Luis Amaya, Diego Carreño

Abstract:

The main objective of this study is to design a mathematical model for the logistics of mining collection centers in the northern region of the department of Boyacá (Colombia), determining the structure that facilitates the flow of products along the supply chain. In order to achieve this, it is necessary to define a suitable design of the distribution network, taking into account the products, customer’s characteristics and the availability of information. Likewise, some other aspects must be defined, such as number and capacity of collection centers to establish, routes that must be taken to deliver products to the customers, among others. This research will use one of the operation research problems, which is used in the design of distribution networks known as Location Routing Problem (LRP).

Keywords: location routing problem, logistic, mining collection, model

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4952 Acupoint Injection of High Concentration of Glucose Attenuates Mice Chronic Pain and Depression Comorbidity

Authors: Chanya Inprasit, Yi-Wen Lin

Abstract:

Inflammation causes changes of peripheral and central nervous system properties, affecting both neuronal and non-neuronal cells, resulting in inflammatory pain. Acupoint injection (AI) was developed in the 1950s and has been widely used for relieving pain. It is an acupoint-stimulating technique that utilizes anatomically based meridians derived from Chinese medicine theory. AI has been accepted as an effective treatment and is thought to display superior results when compared to traditional acupuncture methods. However, the mechanism of AI needs to be ratified by more scientific evidence in order to support the theory and its therapeutic development. In this study, we explored the effect of AI on the comorbidity of chronic pain and depression. Mice hindpaw was injected by complete Freund’s adjuvant (CFA) to induce the condition of chronic pain. Measurements of mechanical and thermal hyperalgesia and depression-like behavior were analyzed. The results indicated a positive tendency to AI treatment. The comorbidity of chronic pain and depression was investigated with relation to transient receptor potential V1 (TRPV1) mechanism through the use of TRPV1 gene deletion. The expression of nociceptors such as voltage-gated sodium channels (Navs) or TRPV1, was significantly down-regulated by AI. The expression of inflammation-activated molecules: astrocytic marker glial fibrillary acidic protein (GFAP), the microglial marker Iba-1, S100B, and related kinases, were reversed by AI in both the peripheral and central nervous system. Taken together, these data provided a detailed molecular mechanism of AI-induced analgesia and anti-inflammatory properties. This finding may be utilized for clinical practice to treat chronic pain and depression comorbidity.

Keywords: inflammatory pain, acupoint injection, TRPV1, GFAP, S100B

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4951 Socially Sustainable Urban Rehabilitation Projects: Case Study of Ortahisar, Trabzon

Authors: Elif Berna Var

Abstract:

Cultural, physical, socio-economic, or politic changes occurred in urban areas might be resulted in the decaying period which may cause social problems. As a solution to that, urban renewal projects have been used in European countries since World War II whereas they have gained importance in Turkey after the 1980s. The first attempts were mostly related to physical or economic aspects which caused negative effects on social pattern later. Thus, social concerns have also started to include in renewal processes in developed countries. This integrative approach combining social, physical, and economic aspects promotes creating more sustainable neighbourhoods for both current and future generations. However, it is still a new subject for developing countries like Turkey. Concentrating on Trabzon-Turkey, this study highlights the importance of socially sustainable urban renewal processes especially in historical neighbourhoods where protecting the urban identity of the area is vital, as well as social structure, to create sustainable environments. Being in the historic city centre and having remarkable traditional houses, Ortahisar is an important image for Trabzon. Because of the fact that architectural and historical pattern of the area is still visible but need rehabilitations, it is preferred to use 'urban rehabilitation' as a way of urban renewal method for this study. A project is developed by the local government to create a secondary city centre and a new landmark for the city. But it is still ambiguous if this project can provide social sustainability of area which is one of the concerns of the research. In the study, it is suggested that social sustainability of an area can be achieved by several factors. In order to determine the factors affecting the social sustainability of an urban rehabilitation project, previous studies have been analysed and some common features are attempted to define. To achieve this, firstly, several analyses are conducted to find out social structure of Ortahisar. Secondly, structured interviews are implemented to 150 local people which aims to measure satisfaction level, awareness, the expectation of them, and to learn their demographical background in detail. Those data are used to define the critical factors for a more socially sustainable neighbourhood in Ortahisar. Later, the priority of those factors is asked to 50 experts and 150 local people to compare their attitudes and to find common criterias. According to the results, it can be said that social sustainability of Ortahisar neighbourhood can be improved by considering various factors like quality of urban areas, demographical factors, public participation, social cohesion and harmony, proprietorial factors, facilities of education and employment. In the end, several suggestions are made for Ortahisar case to promote more socially sustainable urban neighbourhood. As a pilot study highlighting the importance of social sustainability, it is hoped that this attempt might be the contributory effect on achieving more socially sustainable urban rehabilitation projects in Turkey.

Keywords: urban rehabilitation, social sustainability, Trabzon, Turkey

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4950 Analyzing Temperature and Pressure Performance of a Natural Air-Circulation System

Authors: Emma S. Bowers

Abstract:

Perturbations in global environments and temperatures have heightened the urgency of creating cost-efficient, energy-neutral building techniques. Structural responses to this thermal crisis have included designs (including those of the building standard PassivHaus) with airtightness, window placement, insulation, solar orientation, shading, and heat-exchange ventilators as potential solutions or interventions. Limitations in the predictability of the circulation of cooled air through the ambient temperature gradients throughout a structure are one of the major obstacles facing these enhanced building methods. A diverse range of air-cooling devices utilizing varying technologies is implemented around the world. Many of them worsen the problem of climate change by consuming energy. Using natural ventilation principles of air buoyancy and density to circulate fresh air throughout a building with no energy input can combat these obstacles. A unique prototype of an energy-neutral air-circulation system was constructed in order to investigate potential temperature and pressure gradients related to the stack effect (updraft of air through a building due to changes in air pressure). The stack effect principle maintains that since warmer air rises, it will leave an area of low pressure that cooler air will rush in to fill. The result is that warmer air will be expelled from the top of the building as cooler air is directed through the bottom, creating an updraft. Stack effect can be amplified by cooling the air near the bottom of a building and heating the air near the top. Using readily available, mostly recyclable or biodegradable materials, an insulated building module was constructed. A tri-part construction model was utilized: a subterranean earth-tube heat exchanger constructed of PVC pipe and placed in a horizontally oriented trench, an insulated, airtight cube aboveground to represent a building, and a solar chimney (painted black to increase heat in the out-going air). Pressure and temperature sensors were placed at four different heights within the module as well as outside, and data was collected for a period of 21 days. The air pressures and temperatures over the course of the experiment were compared and averaged. The promise of this design is that it represents a novel approach which directly addresses the obstacles of air flow and expense, using the physical principle of stack effect to draw a continuous supply of fresh air through the structure, using low-cost and readily available materials (and zero manufactured energy). This design serves as a model for novel approaches to creating temperature controlled buildings using zero energy and opens the door for future research into the effects of increasing module scale, increasing length and depth of the earth tube, and shading the building. (Model can be provided).

Keywords: air circulation, PassivHaus, stack effect, thermal gradient

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4949 Effect of Sub Supercritical CO2 Processing on Microflora and Shelf Life Tempe

Authors: M. Kustyawati, F. Pratama, D. Saputra, A. Wijaya

Abstract:

Tempe composes of not only molds but also bacteria and yeasts. The structure of microorganisms needs to be in balance number in order the tempe to be an acceptable quality for an extended time. Sub supercritical carbon dioxide can be a promising preservation method for tempe as it induces microbial inactivation avoiding alterations of its quality attributes. Fresh tempe were processed using supercritical and sub supercritical CO2 for a defined holding times, then the growth ability of molds and bacteria were analyzed. The results showed that the supercritical CO2 processing for 5 minutes reduced the number of bacteria and molds to 0.30 log cycle and 1.17 log cycles, respectively. In addition, sub supercritical CO2 processing for 20 minutes had fungicidal effect against mold tempe; whereas, the sub supercritical CO2 for 10 minutes had reducing effect against bacteria tempe, and had fungistatic affect against mold tempe. It suggested that sub-supercritical CO2 processing for 10 min could be useful alternative technique for preservation of tempe.

Keywords: tempe, sub supercritical CO2, fungistatic effect, preservation

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4948 Multidimensional Item Response Theory Models for Practical Application in Large Tests Designed to Measure Multiple Constructs

Authors: Maria Fernanda Ordoñez Martinez, Alvaro Mauricio Montenegro

Abstract:

This work presents a statistical methodology for measuring and founding constructs in Latent Semantic Analysis. This approach uses the qualities of Factor Analysis in binary data with interpretations present on Item Response Theory. More precisely, we propose initially reducing dimensionality with specific use of Principal Component Analysis for the linguistic data and then, producing axes of groups made from a clustering analysis of the semantic data. This approach allows the user to give meaning to previous clusters and found the real latent structure presented by data. The methodology is applied in a set of real semantic data presenting impressive results for the coherence, speed and precision.

Keywords: semantic analysis, factorial analysis, dimension reduction, penalized logistic regression

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4947 Winged Test Rocket with Fully Autonomous Guidance and Control for Realizing Reusable Suborbital Vehicle

Authors: Koichi Yonemoto, Hiroshi Yamasaki, Masatomo Ichige, Yusuke Ura, Guna S. Gossamsetti, Takumi Ohki, Kento Shirakata, Ahsan R. Choudhuri, Shinji Ishimoto, Takashi Mugitani, Hiroya Asakawa, Hideaki Nanri

Abstract:

This paper presents the strategic development plan of winged rockets WIRES (WInged REusable Sounding rocket) aiming at unmanned suborbital winged rocket for demonstrating future fully reusable space transportation technologies, such as aerodynamics, Navigation, Guidance and Control (NGC), composite structure, propulsion system, and cryogenic tanks etc., by universities in collaboration with government and industries, as well as the past and current flight test results.

Keywords: autonomous guidance and control, reusable rocket, space transportation system, suborbital vehicle, winged rocket

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4946 Sol-Gel Coated Fabric for Controlled Release of Mosquito Repellent

Authors: Bhaskar M. Murai, Neeraj Banchor, Ishveen Chabbra, Madhusudhan Nadgir, S. Vidhya

Abstract:

Sol-gel technology combined with electronics and biochemistry helps to overcome the problems caused by mosquitoes by developing a portable, low-cost device which enables controlled release of trapped compound inside it. It is a wet-chemical technique which is used primarily for fabrication of silicate gel which is usually allowed to dry as per requirement. The outcome is solid rock hard material which is porous and has lots of applications in different fields. Taking porosity as a key factor, allethrin a naturally occurring synthetic compound with molecular mass 302.40 was entrapped inside the sol-gel matrix as a dopant. Allethrin is commonly used as an insecticide and is a key ingredient in commercially available mosquitoes repellent in Asian and subtropical countries. It has low toxicity for humans and birds, and are used in many household insecticides such as RAID as well as mosquito coils. They are however highly toxic to fish and bees. Insects subject to its exposure become paralyzed (nervous system effect) before dying. They are also used as an ultra-low volume spray for outdoor mosquito control. Therefore, there is a need for controlled release of allethrin in the environment. For controlled release of allethrin from sol-gel matrix, its (allethrin) we utilized temperature based controlled evaporation through porous sol-gel. Different types of fabric like cotton, Terri-cotton, polyester, surgical cap, knee-cap etc are studied and the best with maximum absorption capacity is selected to hold the sol-gel matrix with maximum quantity. For sol-gel coating 2 x 2cm cloth pieces are dipped in sol-gel solution for 10 minutes and by calculating the weight difference we concluded that Terri cotton is best suitable for our project. An electronic circuit with heating plate is developed in to test the controlled release of compound. An oscillatory circuit is used to produce the required heat.

Keywords: sol-gel, allethrin, TEOS, biochemistry

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4945 Electrophysical and Thermoelectric Properties of Nano-scaled In2O3:Sn, Zn, Ga-Based Thin Films: Achievements and Limitations for Thermoelectric Applications

Authors: G. Korotcenkov, V. Brinzari, B. K. Cho

Abstract:

The thermoelectric properties of nano-scaled In2O3:Sn films deposited by spray pyrolysis are considered in the present report. It is shown that multicomponent In2O3:Sn-based films are promising material for the application in thermoelectric devices. It is established that the increase in the efficiency of thermoelectric conversion at CSn~5% occurred due to nano-scaled structure of the films studied and the effect of the grain boundary filtering of the low energy electrons. There are also analyzed the limitations that may appear during such material using in devices developed for the market of thermoelectric generators and refrigerators. Studies showed that the stability of nano-scaled film’s parameters is the main problem which can limit the application of these materials in high temperature thermoelectric converters.

Keywords: energy conversion technologies, thermoelectricity, In2O3-based films, power factor, nanocomposites, stability

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4944 Fabrication of Highly Conductive Graphene/ITO Transparent Bi-Film through Chemical Vapor Deposition (CVD) and Organic Additives-Free Sol-Gel Techniques

Authors: Bastian Waduge Naveen Harindu Hemasiri, Jae-Kwan Kim, Ji-Myon Lee

Abstract:

Indium tin oxide (ITO) remains the industrial standard transparent conducting oxides with better performances. Recently, graphene becomes as a strong material with unique properties to replace the ITO. However, graphene/ITO hybrid composite material is a newly born field in the electronic world. In this study, the graphene/ITO composite bi-film was synthesized by a two steps process. 10 wt.% tin-doped, ITO thin films were produced by an environmentally friendly aqueous sol-gel spin coating technique with economical salts of In(NO3)3.H2O and SnCl4 without using organic additives. The wettability and surface free energy (97.6986 mJ/m2) enhanced oxygen plasma treated glass substrates were used to form voids free continuous ITO film. The spin-coated samples were annealed at 600 0C for 1 hour under low vacuum conditions to obtained crystallized, ITO film. The crystal structure and crystalline phases of ITO thin films were analyzed by X-ray diffraction (XRD) technique. The Scherrer equation was used to determine the crystallite size. Detailed information about chemical composition and elemental composition of the ITO film were determined by X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX) coupled with FE-SEM respectively. Graphene synthesis was done under chemical vapor deposition (CVD) method by using Cu foil at 1000 0C for 1 min. The quality of the synthesized graphene was characterized by Raman spectroscopy (532nm excitation laser beam) and data was collected at room temperature and normal atmosphere. The surface and cross-sectional observation were done by using FE-SEM. The optical transmission and sheet resistance were measured by UV-Vis spectroscopy and four point probe head at room temperature respectively. Electrical properties were also measured by using V-I characteristics. XRD patterns reveal that the films contain the In2O3 phase only and exhibit the polycrystalline nature of the cubic structure with the main peak of (222) plane. The peak positions of In3d5/2 (444.28 eV) and Sn3d5/2 (486.7 eV) in XPS results indicated that indium and tin are in the oxide form only. The UV-visible transmittance shows 91.35 % at 550 nm with 5.88 x 10-3 Ωcm specific resistance. The G and 2D band in Raman spectroscopy of graphene appear at 1582.52 cm-1 and 2690.54 cm-1 respectively when the synthesized CVD graphene on SiO2/Si. The determined intensity ratios of 2D to G (I2D/IG) and D to G (ID/IG) were 1.531 and 0.108 respectively. However, the above-mentioned G and 2D peaks appear at 1573.57 cm-1 and 2668.14 cm-1 respectively when the CVD graphene on the ITO coated glass, the positions of G and 2D peaks were red shifted by 8.948 cm-1 and 22.396 cm-1 respectively. This graphene/ITO bi-film shows modified electrical properties when compares with sol-gel derived ITO film. The reduction of sheet resistance in the bi-film was 12.03 % from the ITO film. Further, the fabricated graphene/ITO bi-film shows 88.66 % transmittance at 550 nm wavelength.

Keywords: chemical vapor deposition, graphene, ITO, Raman Spectroscopy, sol-gel

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4943 Sustainable Traditional Urban Design of the Old City of Ghadames

Authors: Hazem Bunkheila

Abstract:

Ghadames is an oasis on the edge of the Sahara Desert in southwestern Libya at the border with Algeria and Tunisia. It is the oldest oasis in the world that provides a fascinating example of traditional urban in the desert environment. The urban of the small city is considered a genuine adaptation to the harsh desert climate. The historic city of Ghadames remained unaffected by the rapid after oil changes. That makes it a good field to study sustainable, vernacular, earth architecture and urban design. The aim of this paper is to investigate the urban structure, concept, and fabric of the old oasis. The research also surveys the environmental considerations in the city that shades the sustainable features in this traditional residential area. In addition, the paper addresses the modern applications in the new city of Ghadams and sides of success and failure compared to the traditional urban fabric.

Keywords: dessert climate design, Ghadames, sustainable urban design, traditional urban design

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4942 ReS, Resonant String Shell: Development of an Acoustic Shell for Outdoor Chamber Music Concerts

Authors: Serafino Di Rosario

Abstract:

ReS is a sustainable hand-built temporary acoustic shell, developed since 2011 and built during the architectural workshop at Villa Pennisi in Musica in Acireale, Sicily, each year since 2012. The design concept aims to provide a portable structure by reducing the on-site construction problems and the skills required by the builders together with maximizing the acoustic performance for the audience and the musicians. The shell is built using only wood, recycled for the most part, and can be built and dismantled by non-specialized workers in just three days. This paper describes the research process, which spans over four years and presents the final results in form of acoustic simulations performed by acoustic modeling software and real world measurements. ReS is developed by the ReS team who has been presented with the Peter Lord Award in 2015 by the Institute of Acoustics in the UK.

Keywords: acoustic shell, outdoor natural amplification, computational design, room acoustics

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4941 5iD Viewer: Observation of Fish School Behaviour in Labyrinths and Use of Semantic and Syntactic Entropy for School Structure Definition

Authors: Dalibor Štys, Kryštof M. Stys, Maryia Chkalova, Petr Kouba, Aliaxandr Pautsina, Dalibor Štys Jr., Jana Pečenková, Denis Durniev, Tomáš Náhlík, Petr Císař

Abstract:

In this article, a construction and some properties of the 5iD viewer, the system recording simultaneously five views of a given experimental object is reported. Properties of the system are demonstrated on the analysis of fish schooling behavior. It is demonstrated the method of instrument calibration which allows inclusion of image distortion and it is proposed and partly tested also the method of distance assessment in the case that only two opposite cameras are available. Finally, we demonstrate how the state trajectory of the behavior of the fish school may be constructed from the entropy of the system.

Keywords: 3D positioning, school behavior, distance calibration, space vision, space distortion

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4940 Synthesis of Fullerene Nanorods for Detection of Ethylparaben an Endocrine Disruptor in Cosmetics

Authors: Jahangir Ahmad Rather, Emad A. Khudaish, Ahsanulhaq Qurashi, Palanisamy Kannan

Abstract:

Chemical modification and assembling of fullerenes are fundamentally important for the application of fullerenes as functional molecules and in molecular devices and organic electronic devices. We have synthesized fullerene nanorods C60NRs conjugate via liquid-liquid interface and the synthesized C60NRs was characterized by FTIR spectroscopy, field emission electron microscopy (FESEM) and X-ray diffraction techniques. The C60NRs were immobilized on glassy carbon electrode via surface bound diazonium salts as an impact strategy. This method involves electrografting of p–nitrophenyl to give GCE–Ph–NO2 and then the terminal nitro-group was chemically reduced to GCE–Ph–NH2 in a presence of sodium borohydride/gold–polyaniline nanocomposite (NaBH4/Au–PANI). The Au–PANI composite was synthesized and characterized by FTIR, UV-vis, SEM and EDX techniques. The C60NRs were immobilized on GCE–Ph–NH2 via amination reaction which involves N-H addition across a π-bond on [60] fullerene. The immobilized C60NRs/GCE was subjected to electrochemical reduction in 1.0 M KOH to yield ERC60NRs/GCE sensor. The developed sensor shows high electrocatalytic activity for the detection of ethylparaben (EP) over a concentration range from 0.01 to 0.52 µM with a detection limit (LOD) 3.8 nM. The amount of EP present in the nourishing repair cream (OlAY®) was determined by standard addition method at the developed ERC60NRs/GCE sensor. The total concentration of EP was found to be 0.011 µM (0.1%) and is within the permissible limit of 0.19 % EP in cosmetics according to the European scientific committee (SCCS) on consumer safety on 22 March 2011 (SCCS/1348/11).

Keywords: diazonium salt reduction, ethylparaben (EP), endocrine disruptor, fullerene nanorods (C60NRs), gold–polyaniline nanocomposite (Au–PANI)

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4939 ATC in Competitive Electricity Market Using TCSC

Authors: S. K. Gupta, Richa Bansal

Abstract:

In a deregulated power system structure, power producers, and customers share a common transmission network for wheeling power from the point of generation to the point of consumption. All parties in this open access environment may try to purchase the energy from the cheaper source for greater profit margins, which may lead to overloading and congestion of certain corridors of the transmission network. This may result in violation of line flow, voltage and stability limits and thereby undermine the system security. Utilities therefore need to determine adequately their Available Transfer Capability (ATC) to ensure that system reliability is maintained while serving a wide range of bilateral and multilateral transactions. This paper presents power transfer distribution factor based on AC load flow for the determination and enhancement of ATC. The study has been carried out for IEEE 24 bus Reliability Test System.

Keywords: available transfer capability, FACTS devices, power transfer distribution factors, electric

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4938 Hybrid Artificial Bee Colony and Least Squares Method for Rule-Based Systems Learning

Authors: Ahcene Habbi, Yassine Boudouaoui

Abstract:

This paper deals with the problem of automatic rule generation for fuzzy systems design. The proposed approach is based on hybrid artificial bee colony (ABC) optimization and weighted least squares (LS) method and aims to find the structure and parameters of fuzzy systems simultaneously. More precisely, two ABC based fuzzy modeling strategies are presented and compared. The first strategy uses global optimization to learn fuzzy models, the second one hybridizes ABC and weighted least squares estimate method. The performances of the proposed ABC and ABC-LS fuzzy modeling strategies are evaluated on complex modeling problems and compared to other advanced modeling methods.

Keywords: automatic design, learning, fuzzy rules, hybrid, swarm optimization

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4937 Stability Study of Hydrogel Based on Sodium Alginate/Poly (Vinyl Alcohol) with Aloe Vera Extract for Wound Dressing Application

Authors: Klaudia Pluta, Katarzyna Bialik-Wąs, Dagmara Malina, Mateusz Barczewski

Abstract:

Hydrogel networks, due to their unique properties, are highly attractive materials for wound dressing. The three-dimensional structure of hydrogels provides tissues with optimal moisture, which supports the wound healing process. Moreover, a characteristic feature of hydrogels is their absorption properties which allow for the absorption of wound exudates. For the fabrication of biomedical hydrogels, a combination of natural polymers ensuring biocompatibility and synthetic ones that provide adequate mechanical strength are often used. Sodium alginate (SA) is one of the polymers widely used in wound dressing materials because it exhibits excellent biocompatibility and biodegradability. However, due to poor strength properties, often alginate-based hydrogel materials are enhanced by the addition of another polymer such as poly(vinyl alcohol) (PVA). This paper is concentrated on the preparation methods of sodium alginate/polyvinyl alcohol hydrogel system incorporating Aloe vera extract and glycerin for wound healing material with particular focus on the role of their composition on structure, thermal properties, and stability. Briefly, the hydrogel preparation is based on the chemical cross-linking method using poly(ethylene glycol) diacrylate (PEGDA, Mn = 700 g/mol) as a crosslinking agent and ammonium persulfate as an initiator. In vitro degradation tests of SA/PVA/AV hydrogels were carried out in Phosphate-Buffered Saline (pH – 7.4) as well as in distilled water. Hydrogel samples were firstly cut into half-gram pieces (in triplicate) and immersed in immersion fluid. Then, all specimens were incubated at 37°C and then the pH and conductivity values were measurements at time intervals. The post-incubation fluids were analyzed using SEC/GPC to check the content of oligomers. The separation was carried out at 35°C on a poly(hydroxy methacrylate) column (dimensions 300 x 8 mm). 0.1M NaCl solution, whose flow rate was 0.65 ml/min, was used as the mobile phase. Three injections with a volume of 50 µl were made for each sample. The thermogravimetric data of the prepared hydrogels were collected using a Netzsch TG 209 F1 Libra apparatus. The samples with masses of about 10 mg were weighed separately in Al2O3 crucibles and then were heated from 30°C to 900°C with a scanning rate of 10 °C∙min−1 under a nitrogen atmosphere. Based on the conducted research, a fast and simple method was developed to produce potential wound dressing material containing sodium alginate, poly(vinyl alcohol) and Aloe vera extract. As a result, transparent and flexible SA/PVA/AV hydrogels were obtained. The degradation experiments indicated that most of the samples immersed in PBS as well as in distilled water were not degraded throughout the whole incubation time.

Keywords: hydrogels, wound dressings, sodium alginate, poly(vinyl alcohol)

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4936 Combining Transcriptomics, Bioinformatics, Biosynthesis Networks and Chromatographic Analyses for Cotton Gossypium hirsutum L. Defense Volatiles Study

Authors: Ronald Villamar-Torres, Michael Staudt, Christopher Viot

Abstract:

Cotton Gossypium hirsutum L. is one of the most important industrial crops, producing the world leading natural textile fiber, but is very prone to arthropod attacks that reduce crop yield and quality. Cotton cultivation, therefore, makes an outstanding use of chemical pesticides. In reaction to herbivorous arthropods, cotton plants nevertheless show natural defense reactions, in particular through volatile organic compounds (VOCs) emissions. These natural defense mechanisms are nowadays underutilized but have a very high potential for cotton cultivation, and elucidating their genetic bases will help to improve their use. Simulating herbivory attacks by mechanical wounding of cotton plants in greenhouse, we studied by qPCR the changes in gene expression for genes of the terpenoids biosynthesis pathway. Differentially expressed genes corresponded to higher levels of the terpenoids biosynthesis pathway and not to enzymes synthesizing particular terpenoids. The genes were mapped on the G. hirsutum L. reference genome; their global relationships inside the general metabolic pathways and the biosynthesis of secondary metabolites were visualized with iPath2. The chromatographic profiles of VOCs emissions indicated first monoterpenes and sesquiterpenes emissions, dominantly four molecules known to be involved in plant reactions to arthropod attacks. As a result, the study permitted to identify potential key genes for the emission of volatile terpenoids by cotton plants in reaction to an arthropod attack, opening possibilities for molecular-assisted cotton breeding in benefit of smallholder cotton growers.

Keywords: biosynthesis pathways, cotton, mechanisms of plant defense, terpenoids, volatile organic compounds

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4935 New Refrigerant La₀.₇Ca₀.₁₅Sr₀.₁₅Mn₁₋ₓGaₓO₃ for Application in Magnetic Refrigeration

Authors: Essebti Dhahri

Abstract:

We present a new refrigerant La₀.₇Ca₀.₁₅Sr₀.₁₅Mn₁₋ₓGaₓO₃ (x = 0.0-0.1) manganites. These compounds were prepared by the sol-gel method. The refinement of the X-ray diffraction reveals that all samples crystallize in a rhombohedral structure (space group R3 ̅c). Detailed measurements of the magnetization as a function of temperature and magnetic applied field M (µ₀H, T) were carried out. From the M(µ₀H, T) curves, we have calculated the magnetic entropy change (ΔSM) according to the Maxwell relation. The temperature dependence of the magnetization M(T) reveals a decrease of M when increasing the x content. The magnetic entropy change (ΔSM) reaches a maximum value near room temperature. It was also found that this compound exhibits a large magnetocaloric effect MCE which increases when decreasing Ga concentration. So, the studied compounds could be considered potential materials for magnetic refrigeration application.

Keywords: magnetic measurements, Rietveld refinement, magnetic refrigeration, magnetocaloric effect

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4934 Passivization: as Syntactic Argument Decreasing Parameter in Boro

Authors: Ganga Brahma

Abstract:

Boro employs verbs hooked up with morphemes which lead verbs to adjust with their arguments and hence, affecting the whole of sentence structures. This paper is based on few such syntactic parameters which are usually considered as argument decreasing parameters in linguistic works. Passivizing of few transitive clauses which are usually construed from the verbs occurring with certain morphemes and representation in middle constructions are few of such strategies which lead to conceptualizing of decreasing of syntactic arguments from a sentence. This paper focuses on the mentioned linguistic strategies and attempts to describe the linguistic processes as for how these parameters work in languages especially by concentrating on a particular Tibeto-Burman language i.e. Boro. Boro is a Tibeto-Burman language widely spoken in parts of the north-eastern regions of India. It has an agglutinative nature in forming words as well as clauses. There is a morpheme ‘za’ which means ‘to happen, become’ in Boro whose appearances with verb roots denotes an idea of the subject being passivized. Passivization, usually has notions that it is a reversed representation of its active sentence forms in the terms of argument placements. (However, it is not accountably true as passives and actives have some distinct features of their own and independent of one and the other.) This particular work will concentrate on the semantics of passivization at the same time along with its syntactic reality. The verb khɑo meaning ‘to steal’ offers a sense of passivization with the appearance of the morpheme zɑ which means ‘to happen, become’ (e.g Zunu-ɑ lama-ɑo phɯisɑ khɑo-zɑ-bɑi; Junu-NOM road-LOC money steal-PASS-PRES: Junu got her money stolen on the road). The focus, here, is more on the argument placed at the subject position (i.e. Zunu) and the event taken place. The semantics of such construction asks for the agent because without an agent the event could not have taken place. However, the syntactic elements fill the slots of relegated or temporarily deleted agent which, infact, is the actual subject cum agent in its active representation. Due to the event marker ‘zɑ’ in this presentation it affords to reduce one participant from such a situation which in actual is made up of three participants. Hence, the structure of di-transitive construction here reduces to mono-transitive structure. Unlike passivization, middle construction does not allow relegation of the agents. It permanently deletes agents. However, it also focuses on the fore-grounded subject and highlighting on the changed states on the subjects which happens to be the underlying objects of their respective transitive structures (with agents). This work intends to describe how these two parameters which are different at their semantic realization can meet together at a syntactic level in order to create a linguistic parameter that decreases participants from their actual structures which are with more than one participant.

Keywords: argument-decrease, middle-construction, passivization, transitivity-intransitivity

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