Search results for: Density Functional Theory (DFT)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10304

Search results for: Density Functional Theory (DFT)

7844 Influence of a Pulsatile Electroosmotic Flow on the Dispersivity of a Non-Reactive Solute through a Microcapillary

Authors: Jaime Muñoz, José Arcos, Oscar Bautista Federico Méndez

Abstract:

The influence of a pulsatile electroosmotic flow (PEOF) at the rate of spread, or dispersivity, for a non-reactive solute released in a microcapillary with slippage at the boundary wall (modeled by the Navier-slip condition) is theoretically analyzed. Based on the flow velocity field developed under such conditions, the present study implements an analytical scheme of scaling known as the Theory of Homogenization, in order to obtain a mathematical expression for the dispersivity, valid at a large time scale where the initial transients have vanished and the solute spreads under the Taylor dispersion influence. Our results show the dispersivity is a function of a slip coefficient, the amplitude of the imposed electric field, the Debye length and the angular Reynolds number, highlighting the importance of the latter as an enhancement/detrimental factor on the dispersivity, which allows to promote the PEOF as a strong candidate for chemical species separation at lab-on-a-chip devices.

Keywords: dispersivity, microcapillary, Navier-slip condition, pulsatile electroosmotic flow, Taylor dispersion, Theory of Homogenization

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7843 Modelling of Exothermic Reactions during Carbon Fibre Manufacturing and Coupling to Surrounding Airflow

Authors: Musa Akdere, Gunnar Seide, Thomas Gries

Abstract:

Carbon fibres are fibrous materials with a carbon atom amount of more than 90%. They combine excellent mechanicals properties with a very low density. Thus carbon fibre reinforced plastics (CFRP) are very often used in lightweight design and construction. The precursor material is usually polyacrylonitrile (PAN) based and wet-spun. During the production of carbon fibre, the precursor has to be stabilized thermally to withstand the high temperatures of up to 1500 °C which occur during carbonization. Even though carbon fibre has been used since the late 1970s in aerospace application, there is still no general method available to find the optimal production parameters and the trial-and-error approach is most often the only resolution. To have a much better insight into the process the chemical reactions during stabilization have to be analyzed particularly. Therefore, a model of the chemical reactions (cyclization, dehydration, and oxidation) based on the research of Dunham and Edie has been developed. With the presented model, it is possible to perform a complete simulation of the fibre undergoing all zones of stabilization. The fiber bundle is modeled as several circular fibers with a layer of air in-between. Two thermal mechanisms are considered to be the most important: the exothermic reactions inside the fiber and the convective heat transfer between the fiber and the air. The exothermic reactions inside the fibers are modeled as a heat source. Differential scanning calorimetry measurements have been performed to estimate the amount of heat of the reactions. To shorten the required time of a simulation, the number of fibers is decreased by similitude theory. Experiments were conducted to validate the simulation results of the fibre temperature during stabilization. The experiments for the validation were conducted on a pilot scale stabilization oven. To measure the fibre bundle temperature, a new measuring method is developed. The comparison of the results shows that the developed simulation model gives good approximations for the temperature profile of the fibre bundle during the stabilization process.

Keywords: carbon fibre, coupled simulation, exothermic reactions, fibre-air-interface

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7842 Cytotoxic Activity of Acetone and Ethanol Overripe Tempe Extracts against MCF-7 Breast Cancer Cells and Their Antioxidant Property

Authors: Dian Muzdalifah, Anastasia F. Devi, Zatil A. Athaillah, Linar Z. Udin

Abstract:

Tempe is a functional food prepared from soybeans through Rhizopus spp fermentation. It is well known as functional food, originated from Indonesia. Most studies on tempe functionalities refer to ripe (48 h fermentation) tempe and only limited studies discuss overripe tempe while longer fermentation time possibly increased tempe health benefit. Hence, the present study was performed to investigate the cytotoxic activity againts MCF-7 breast cancer cells and antioxidant property of tempe prepared from 0–156 h of fermentation. Tempe samples were dried and extracted with acetone and ethanol, respectively. Their extracts were used for subsequent analysis. The cytotoxic activity was assessed on MCF 7 breast cancer cells using Alamar Blue method. The antioxidant activity was determined by DPPH free radical scavenging assay. The results indicated that acetone extracts of 108 h tempe had a potent cytotoxic activity against MCF-7 breast cancer cells (IC50 = 2.54 ± 0,30 μg/mL). Ethanol extracts of 108 h tempe also showed the potency, but at slightly higher IC50 (5.20 ± 1.01 μg/mL). Both acetone and ethanol extracts of 108 and 120 h tempe showed high antioxidant activity expressed as percent inhibition with no significant difference. However, acetone extracts of 120 h tempe (81.31 ± 3.70 %) had better ability to inhibit oxidation reaction than that of ethanol extracts (75.77 ± 6.00 %). It can be concluded that the cytotoxic activity of tempe from 0–156 h of fermentation is positively correlated to their corresponding antioxidant property. Longer fermentation time, up to 108 h, increased the ability of tempe to inhibit the growth of MCF-7 breast cancer cells and oxidative reaction. But extended fermentation time, up to 156 h, tends to decrease its ability. Further studies are encouraged to identify the active components contained in each extract.

Keywords: antioxidant property, cytotoxic activity, extracts, overripe tempeh

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7841 Transdisciplinary Methodological Innovation: Connecting Natural and Social Sciences Research through a Training Toolbox

Authors: Jessica M. Black

Abstract:

Although much of natural and social science research aims to enhance human flourishing and address social problems, the training within the two fields is significantly different across theory, methodology, and implementation of results. Social scientists are trained in social, psychological, and to the extent that it is relevant to their discipline, spiritual development, theory, and accompanying methodologies. They tend not to receive training or learn about accompanying methodology related to interrogating human development and social problems from a biological perspective. On the other hand, those in the natural sciences, and for the purpose of this work, human biological sciences specifically – biology, neuroscience, genetics, epigenetics, and physiology – are often trained first to consider cellular development and related methodologies, and may not have opportunity to receive formal training in many of the foundational principles that guide human development, such as systems theory or person-in-environment framework, methodology related to tapping both proximal and distal psycho-social-spiritual influences on human development, and foundational principles of equity, justice and inclusion in research design. There is a need for disciplines heretofore siloed to know one another, to receive streamlined, easy to access training in theory and methods from one another and to learn how to build interdisciplinary teams that can speak and act upon a shared research language. Team science is more essential than ever, as are transdisciplinary approaches to training and research design. This study explores the use of a methodological toolbox that natural and social scientists can use by employing a decision-making tree regarding project aims, costs, and participants, among other important study variables. The decision tree begins with a decision about whether the researcher wants to learn more about social sciences approaches or biological approaches to study design. The toolbox and platform are flexible, such that users could also choose among modules, for instance, reviewing epigenetics or community-based participatory research even if those are aspects already a part of their home field. To start, both natural and social scientists would receive training on systems science, team science, transdisciplinary approaches, and translational science. Next, social scientists would receive training on grounding biological theory and the following methodological approaches and tools: physiology, (epi)genetics, non-invasive neuroimaging, invasive neuroimaging, endocrinology, and the gut-brain connection. Natural scientists would receive training on grounding social science theory, and measurement including variables, assessment and surveys on human development as related to the developing person (e.g., temperament and identity), microsystems (e.g., systems that directly interact with the person such as family and peers), mesosystems (e.g., systems that interact with one another but do not directly interact with the individual person, such as parent and teacher relationships with one another), exosystems (e.g., spaces and settings that may come back to affect the individual person, such as a parent’s work environment, but within which the individual does not directly interact, macrosystems (e.g., wider culture and policy), and the chronosystem (e.g., historical time, such as the generational impact of trauma). Participants will be able to engage with the toolbox and one another to foster increased transdisciplinary work

Keywords: methodology, natural science, social science, transdisciplinary

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7840 [Keynote Talk]: Existence of Random Fixed Point Theorem for Contractive Mappings

Authors: D. S. Palimkar

Abstract:

Random fixed point theory has received much attention in recent years, and it is needed for the study of various classes of random equations. The study of random fixed point theorems was initiated by the Prague school of probabilistic in the 1950s. The existence and uniqueness of fixed points for the self-maps of a metric space by altering distances between the points with the use of a control function is an interesting aspect in the classical fixed point theory. In a new category of fixed point problems for a single self-map with the help of a control function that alters the distance between two points in a metric space which they called an altering distance function. In this paper, we prove the results of existence of random common fixed point and its uniqueness for a pair of random mappings under weakly contractive condition for generalizing alter distance function in polish spaces using Random Common Fixed Point Theorem for Generalized Weakly Contractions.

Keywords: Polish space, random common fixed point theorem, weakly contractive mapping, altering function

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7839 Study of Bagmati River Pollution Level and Remediation of Heavy Metal using Microbial Fuel Cell

Authors: Jarina Joshi, Sujeeta Maharjan

Abstract:

This study was used to assess the potential of MFCs in removing heavy metals from the urban Bagmati River while (2) simultaneously producing electricity. Upon physicochemical and biological analysis of the collected water samples from three different locations during summer and winter, it was found that the Chemical Oxygen Demand (COD) and Total Suspended Solid (TSS) values exceeded the Ministry of Environment’s (MOE 2010) guidelines, and the river was contaminated with lead (Pb). The meta-genomic analysis, revealed the presence of four electrogenic bacterial genera: Pseudomonas, Rhodobacter, Rhodoferax, and Shewanella. Upon attainment of optimal configuration - COD 3500mg/L, a Graphite rod anode (TSA-13.31cm2), Platinum cathode (10×10×0.5mm) as electrodes, and a 1% bacterial consortium- MFCs with inoculum enriched Bagmati water, showed a maximum voltage of 0.08 ± 0.001 V, a current density of 0.8 ± 0.01 A/m2, and a power density of 0.070 ± 0.002 W/m2. Comparatively higher metal removal was also achieved in this operation, with approximately 100% As (III), 99% Pb (II), 98% Hg (II), and at least 25% Cr (VI) removal. Our results highlight MFC to be able to remediate heavy metals and also generating electricity. The research showed that though the pollution in Bagmati River had decreased in terms of parametric concentrations as researched in Baniya et al, 2019, it is still polluted exceeding guideline values, possibly indicating distortion of natural restoration capacity of river. Additionally, it also showed that with downstream flow of river, it indeed becomes less polluted but human activities isn’t letting this natural process to revive.

Keywords: bagmati, heavy metal contamination, heavy metal remediation, bio-electricity

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7838 Normalized Difference Vegetation Index and Normalize Difference Chlorophyll Changes with Different Irrigation Levels on Sillage Corn

Authors: Cenk Aksit, Suleyman Kodal, Yusuf Ersoy Yildirim

Abstract:

Normalized Difference Vegetation Index (NDVI) is a widely used index in the world that provides reference information, such as the health status of the plant, and the density of the vegetation in a certain area, by making use of the electromagnetic radiation reflected from the plant surface. On the other hand, the chlorophyll index provides reference information about the chlorophyll density in the plant by making use of electromagnetic reflections at certain wavelengths. Chlorophyll concentration is higher in healthy plants and decreases as plant health decreases. This study, it was aimed to determine the changes in Normalize Difference Vegetation Index (NDVI) and Normalize Difference Chlorophyll (NDCI) of silage corn irrigated with subsurface drip irrigation systems under different irrigation levels. In 5 days irrigation interval, the daily potential plant water consumption values were collected, and the calculated amount was applied to the full irrigation and 3 irrigation water levels as irrigation water. The changes in NDVI and NDCI of silage corn irrigated with subsurface drip irrigation systems under different irrigation levels were determined. NDVI values have changed according to the amount of irrigation water applied, and the highest NDVI value has been reached in the subject where the most water is applied. Likewise, it was observed that the chlorophyll value decreased in direct proportion to the amount of irrigation water as the plant approached the harvest.

Keywords: NDVI, NDCI, sub-surface drip irrigation, silage corn, deficit irrigation

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7837 Composition Dependence of Ni 2p Core Level Shift in Fe1-xNix Alloys

Authors: Shakti S. Acharya, V. R. R. Medicherla, Rajeev Rawat, Komal Bapna, Deepnarayan Biswas, Khadija Ali, K. Maiti

Abstract:

The discovery of invar effect in 35% Ni concentration Fe1-xNix alloy has stimulated enormous experimental and theoretical research. Elemental Fe and low Ni concentration Fe1-xNix alloys which possess body centred cubic (bcc) crystal structure at ambient temperature and pressure transform to hexagonally close packed (hcp) phase at around 13 GPa. Magnetic order was found to be absent at 11K for Fe92Ni8 alloy when subjected to a high pressure of 26 GPa. The density functional theoretical calculations predicted substantial hyperfine magnetic fields, but were not observed in Mossbaur spectroscopy. The bulk modulus of fcc Fe1-xNix alloys with Ni concentration more than 35%, is found to be independent of pressure. The magnetic moment of Fe is also found be almost same in these alloys from 4 to 10 GPa pressure. Fe1-xNix alloys exhibit a complex microstructure which is formed by a series of complex phase transformations like martensitic transformation, spinodal decomposition, ordering, mono-tectoid reaction, eutectoid reaction at temperatures below 400°C. Despite the existence of several theoretical models the field is still in its infancy lacking full knowledge about the anomalous properties exhibited by these alloys. Fe1-xNix alloys have been prepared by arc melting the high purity constituent metals in argon ambient. These alloys have annealed at around 3000C in vacuum sealed quartz tube for two days to make the samples homogeneous. These alloys have been structurally characterized by x-ray diffraction and were found to exhibit a transition from bcc to fcc for x > 0.3. Ni 2p core levels of the alloys have been measured using high resolution (0.45 eV) x-ray photoelectron spectroscopy. Ni 2p core level shifts to lower binding energy with respect to that of pure Ni metal giving rise to negative core level shifts (CLSs). Measured CLSs exhibit a linear dependence in fcc region (x > 0.3) and were found to deviate slightly in bcc region (x < 0.3). ESCA potential model fails correlate CLSs with site potentials or charges in metallic alloys. CLSs in these alloys occur mainly due to shift in valence bands with composition due to intra atomic charge redistribution.

Keywords: arc melting, core level shift, ESCA potential model, valence band

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7836 A Theoretical Framework: The Influence of Luxury Companies' Corporate Social Activities on Consumer Purchase Intention

Authors: Kveta Olsanova, Gina Cook, Marija Zlatic

Abstract:

This paper discusses the theoretical framework suggesting the dependencies between luxury brands’ CSR (Corporate Social Responsibility) variables and the purchase intention of luxury shoppers. The framework is based on a literature review and in-depth individual interviews with a sample of luxury users and buyers. The measures of the model are based on existing research and the authors' qualitative research results. The model suggests that purchase intention in the luxury segment is dependent on the luxury values (symbolic, experiential, functional and social), individual sustainable dimension (composed of societal, environmental and economic variables) and awareness of the brand’s CSR, the last two relationships being potentially moderated by certain conditions such as demographics and general attitudes towards CSR and sustainability. The model’s output is in the formulation of several hypotheses, to be tested in an upcoming quantitative study. The qualitative phase indicated that the perceived symbolic, functional and experiential value dimensions of luxury brands were stronger drivers of purchase intention compared to the sustainable dimension. The contribution of the research consists of highlighting CSR’s impact on customer purchase intent as a potential implication for luxury brand management due to two aspects: (i) consumer awareness of the existing CSR activities of luxury brands is low, and this might be challenged by the demands of Gen Z entrants into the lux industry as they are known for their positive approach to CSR; (ii) the UN’s SDGs will bring CSR to the attention of all industries, including currently 'CSR silent' segments represented by luxury. Our research should contribute to incorporation of strategic CSR into the policies and strategies of the luxury segment by providing evidence that luxury customers do care.

Keywords: CSR, luxury shoppers, purchase intention, sustainability

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7835 Effect of Different Parameters on the Swelling Behaviour of Thermo-Responsive Elastomers in a Nematogenic Solvent

Authors: Nouria Bouchikhi, Soufiane Bedjaoui, C. Tewfik Bouchaour, Lamia Alachaher Bedjaoui, Ulrich Maschke

Abstract:

Swelling properties and phase diagrams of binary systems composed of liquid crystalline networks and a low molecular mass liquid crystal (LMWLC) have been investigated. The networks were prepared by ultraviolet (UV) irradiation of reactive mixtures including a monomer, a cross-linking agent and a photo-initiator. These networks were prepared using two cross-linking agents: 1,6 hexanedioldiacrylate (HDDA) and a mesogenic acrylic acid 6-(4’-(6-acryloyloxy-hexyloxy) biphenyl-4-yl oxy) hexyl ester (AHBH). The obtained dry networks were characterized by differential scanning calorimetry, and immersed in an excess of a LMWLC solvent 4-cyano-4’-pentylbiphenyl (5CB), forming polymer gels. A detailed study by polarized optical microscopy allowed to determine the swelling degree of the gels and to follow the phase behavior of the solvent inside the polymer matrix in a wide range of temperature. It has been found that the gels undergo a sharp decrease of their swelling degree in response to an infinitesimal change of temperature. This finding adds new and interesting aspects on the actuators applications. We have subsequently explored the effect of different parameters on volume phase transition of these liquid crystalline materials. Such as the cross-linking density (CD), a nature of cross-linking agent and the photo initiator concentration.

Keywords: cross-linking density, liquid crystalline elastomers, phase diagrams, swelling

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7834 Influence of Sr(BO2)2 Doping on Superconducting Properties of (Bi,Pb)-2223 Phase

Authors: N. G. Margiani, I. G. Kvartskhava, G. A. Mumladze, Z. A. Adamia

Abstract:

Chemical doping with different elements and compounds at various amounts represents the most suitable approach to improve the superconducting properties of bismuth-based superconductors for technological applications. In this paper, the influence of partial substitution of Sr(BO2)2 for SrO on the phase formation kinetics and transport properties of (Bi,Pb)-2223 HTS has been studied for the first time. Samples with nominal composition Bi1.7Pb0.3Sr2-xCa2Cu3Oy[Sr(BO2)2]x, x=0, 0.0375, 0.075, 0.15, 0.25, were prepared by the standard solid state processing. The appropriate mixtures were calcined at 845 oC for 40 h. The resulting materials were pressed into pellets and annealed at 837 oC for 30 h in air. Superconducting properties of undoped (reference) and Sr(BO2)2-doped (Bi,Pb)-2223 compounds were investigated through X-ray diffraction (XRD), resistivity (ρ) and transport critical current density (Jc) measurements. The surface morphology changes in the prepared samples were examined by scanning electron microscope (SEM). XRD and Jc studies have shown that the low level Sr(BO2)2 doping (x=0.0375-0.075) to the Sr-site promotes the formation of high-Tc phase and leads to the enhancement of current carrying capacity in (Bi,Pb)-2223 HTS. The doped sample with x=0.0375 has the best performance compared to other prepared samples. The estimated volume fraction of (Bi,Pb)-2223 phase increases from ~25 % for reference specimen to ~70 % for x=0.0375. Moreover, strong increase in the self-field Jc value was observed for this dopant amount (Jc=340 A/cm2), compared to an undoped sample (Jc=110 A/cm2). Pronounced enhancement of superconducting properties of (Bi,Pb)-2223 superconductor can be attributed to the acceleration of high-Tc phase formation as well as the improvement of inter-grain connectivity by small amounts of Sr(BO2)2 dopant.

Keywords: bismuth-based superconductor, critical current density, phase formation, Sr(BO₂)₂ doping

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7833 TA6V Selective Laser Melting as an Innovative Method Produce Complex Shapes

Authors: Rafał Kamiński, Joel Rech, Philippe Bertrand, Christophe Desrayaud

Abstract:

Additive manufacturing is a hot topic for industry. Among the additive techniques, Selective Laser Melting (SLM) becomes even more popular, especially for making parts for aerospace applications, thanks to its design freedom (customized and light structures) and its reduced time to market. However, some functional surfaces have to be machined to achieve small tolerances and low surface roughness to fulfill industry specifications. The complex shapes designed for SLM (ex: titanium turbine blades) necessitate the use of ball end milling operations like in the conventional process after forging. However, the metallurgical state of TA6V is very different from the one obtained usually from forging, because of the laser sintering layer by layer. So this paper aims to investigate the influence of new TA6V metallurgies produced by SLM on the machinability in ball end milling. Machinability is considered as the property of a material to obtain easily and by a cheap way a functional surface. This means, for instance, the property to limit cutting tool wear rate and to get smooth surfaces. So as to reach this objective, SLM parts have been produced and heat treated with various conditions leading to various metallurgies that are compared with a standard equiaxed α+β wrought microstructure. The machinability is analyzed by measuring surface roughness, tool wear and cutting forces for a range of cutting conditions (depth of cut 'ap', feed per tooth 'fz', spindle speed 'N') in accordance with industrial practices. This work has revealed that TA6V produced by SLM can lead to a better machinability that standard wrought alloys.

Keywords: ball milling, selective laser melting, surface roughness, titanium, wear

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7832 Patient Engagement in Healthcare and Health Literacy in China: A Survey in China

Authors: Qing Wu, Xuchun Ye, Qiuchen Wang, Kirsten Corazzini

Abstract:

Objective: It’s increasing acknowledged that patient engagement in healthcare and health literacy both have positive impact on patient outcome. Health literacy emphasizes the ability of individuals to understand and apply health information and manage health. Patients' health literacy affected their willingness to participate in decision-making, but its impact on the behavior and willingness of patient engagement in healthcare is not clear, especially in China. Therefore, this study aimed to explore the correlation between the behavior and willingness of patient engagement and health literacy. Methods: A cross-sectional survey was employed using the behavior and willingness of patient engagement in healthcare questionnaire, Chinese version All Aspects of Health Literacy Scale (AAHLS). A convenient sample of 443 patients was recruited from 8 general hospitals in Shanghai, Jiangsu Province and Zhejiang Province, from September 2016 to January 2017. Results: The mean score for the willingness was (4.41±0.45), and the mean score for the patient engagement behavior was (4.17±0.49); the mean score for the patient's health literacy was (2.36±0.29),the average score of its three dimensions- the functional literacy, the Communicative/interactive literacy and the Critical literacy, was (2.26±0.38), (2.28±0.42), and (2.61±0.43), respectively. Patients' health literacy was positively correlated with their willingness of engagement (r = 0.367, P < 0.01), and positively correlated with patient engagement behavior (r = 0.357, P < 0.01). All dimensions of health literacy were positively correlated with the behavior and willingness of patient engagement in healthcare; the dimension of Communicative/interactive literacy (r = 0.312, P < 0.01; r = 0.357, P < 0.01) and the Critical literacy (r = 0.357, P < 0.01; r = 0.357, P < 0.01) are more relevant to the behavior and willingness than the dimension of basic/functional literacy (r=0.150, P < 0.01; r = 0.150, P < 0.01). Conclusions: The behavior and willingness of patient engagement in healthcare are positively correlated with health literacy and its dimensions. In clinical work, medical staff should pay attention to patients’ health literacy, especially the situation that low literacy leads to low participation and provide health information to patients through health education or communication to improve their health literacy as well as guide them to actively and rationally participate in their own health care.

Keywords: patient engagement, health literacy, healthcare, correlation

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7831 Hydraulic Headloss in Plastic Drainage Pipes at Full and Partially Full Flow

Authors: Velitchko G. Tzatchkov, Petronilo E. Cortes-Mejia, J. Manuel Rodriguez-Varela, Jesus Figueroa-Vazquez

Abstract:

Hydraulic headloss, expressed by the values of friction factor f and Manning’s coefficient n, is an important parameter in designing drainage pipes. Their values normally are taken from manufacturer recommendations, many times without sufficient experimental support. To our knowledge, currently there is no standard procedure for hydraulically testing such pipes. As a result of research carried out at the Mexican Institute of Water Technology, a laboratory testing procedure was proposed and applied on 6 and 12 inches diameter polyvinyl chloride (PVC) and high-density dual wall polyethylene pipe (HDPE) drainage pipes. While the PVC pipe is characterized by naturally smooth interior and exterior walls, the dual wall HDPE pipe has corrugated exterior wall and, although considered smooth, a slightly wavy interior wall. The pipes were tested at full and partially full pipe flow conditions. The tests for full pipe flow were carried out on a 31.47 m long pipe at flow velocities between 0.11 and 4.61 m/s. Water was supplied by gravity from a 10 m-high tank in some of the tests, and from a 3.20 m-high tank in the rest of the tests. Pressure was measured independently with piezometer readings and pressure transducers. The flow rate was measured by an ultrasonic meter. For the partially full pipe flow the pipe was placed inside an existing 49.63 m long zero slope (horizontal) channel. The flow depth was measured by piezometers located along the pipe, for flow rates between 2.84 and 35.65 L/s, measured by a rectangular weir. The observed flow profiles were then compared to computer generated theoretical gradually varied flow profiles for different Manning’s n values. It was found that Manning’s n, that normally is assumed constant for a given pipe material, is in fact dependent on flow velocity and pipe diameter for full pipe flow, and on flow depth for partially full pipe flow. Contrary to the expected higher values of n and f for the HDPE pipe, virtually the same values were obtained for the smooth interior wall PVC pipe and the slightly wavy interior wall HDPE pipe. The explanation of this fact was found in Henry Morris’ theory for smooth turbulent conduit flow over isolated roughness elements. Following Morris, three categories of the flow regimes are possible in a rough conduit: isolated roughness (or semi smooth turbulent) flow, wake interference (or hyper turbulent) flow, and skimming (or quasi-smooth) flow. Isolated roughness flow is characterized by friction drag turbulence over the wall between the roughness elements, independent vortex generation, and dissipation around each roughness element. In this regime, the wake and vortex generation zones at each element develop and dissipate before attaining the next element. The longitudinal spacing of the roughness elements and their height are important influencing agents. Given the slightly wavy form of the HDPE pipe interior wall, the flow for this type of pipe belongs to this category. Based on that theory, an equation for the hydraulic friction factor was obtained. The obtained coefficient values are going to be used in the Mexican design standards.

Keywords: drainage plastic pipes, hydraulic headloss, hydraulic friction factor, Manning’s n

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7830 Chronolgy and Developments in Inventory Control Best Practices for FMCG Sector

Authors: Roopa Singh, Anurag Singh, Ajay

Abstract:

Agriculture contributes a major share in the national economy of India. A major portion of Indian economy (about 70%) depends upon agriculture as it forms the main source of income. About 43% of India’s geographical area is used for agricultural activity which involves 65-75% of total population of India. The given work deals with the Fast moving Consumer Goods (FMCG) industries and their inventories which use agricultural produce as their raw material or input for their final product. Since the beginning of inventory practices, many developments took place which can be categorised into three phases, based on the review of various works. The first phase is related with development and utilization of Economic Order Quantity (EOQ) model and methods for optimizing costs and profits. Second phase deals with inventory optimization method, with the purpose of balancing capital investment constraints and service level goals. The third and recent phase has merged inventory control with electrical control theory. Maintenance of inventory is considered negative, as a large amount of capital is blocked especially in mechanical and electrical industries. But the case is different in food processing and agro-based industries and their inventories due to cyclic variation in the cost of raw materials of such industries which is the reason for selection of these industries in the mentioned work. The application of electrical control theory in inventory control makes the decision-making highly instantaneous for FMCG industries without loss in their proposed profits, which happened earlier during first and second phases, mainly due to late implementation of decision. The work also replaces various inventories and work-in-progress (WIP) related errors with their monetary values, so that the decision-making is fully target-oriented.

Keywords: control theory, inventory control, manufacturing sector, EOQ, feedback, FMCG sector

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7829 Using Plant Oils in Total Mixed Ration on Voluntary Feed Intake and Blood Metabolize of Crossbred Thai Native X American Brahman Cattle

Authors: Wantanee Polviset, N. Prakobsaeng, N. Wetchakama, C. Yuangklang

Abstract:

The aim of this study was to evaluate the effect of soybean oil, palm oil and sunflower oil supplementations in total mixed ration on voluntary feed intake, dry matter (DM) digestibility and blood metabolize in crossbred Thai native x American Brahman Cattle. Three Thai native x American Brahman cattle, one-year-old with liveweight of 116±22.59 kg, were randomly assigned according to a 3 x 3 latin square design. Each period of feeding lasted for 21 days to receive three dietary treatments were soybean oil, palm oil and sunflower oil supplementation at 5%. During the experimental periods, all cattle were fed a diet with total mixed ration containing roughage to concentrate ratio of 40:60 and rice straw was used as a roughage source. Based on the present study, the results revealed that voluntary feed intake (kgDM/head/day) and %BW DM intake were not affected (P>0.05), whereas percentage of dry matter digestibility was greater with the soybean oil supplementation (P<0.01). It was also found that blood glucose, blood urea nitrogen, cholesterol, triglyceride, high density lipoprotein and low density lipoprotein in plasma were similar among treatments. Based on this study, supplementing 5% soybean oil in total mixed ration (TMR) diets was suitable in beef cattle without any effect dry matter digestibility and blood metabolites.

Keywords: plant oils, feed intake, blood metabolize, crossbred Thai native x Brahman cattle

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7828 To Know the Way to the Unknown: A Semi-Experimental Study on the Implication of Skills and Knowledge for Creative Processes in Higher Education

Authors: Mikkel Snorre Wilms Boysen

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From a theoretical perspective, expertise is generally considered a precondition for creativity. The assumption is that an individual needs to master the common and accepted rules and techniques within a certain knowledge-domain in order to create something new and valuable. However, real life cases, and a limited amount of empirical studies, demonstrate that this assumption may be overly simple. In this article, this question is explored through a number of semi-experimental case studies conducted within the fields of music, technology, and youth culture. The studies indicate that, in various ways, expertise plays an important part in creative processes. However, the case studies also indicate that expertise sometimes leads to an entrenched perspective, in the sense that knowledge and experience may work as a path into the well-known rather than into the unknown. In this article, these issues are explored with reference to different theoretical approaches to creativity and learning, including actor-network theory, the theory of blind variation and selective retention, and Csikszentmihalyi’s system model. Finally, some educational aspects and implications of this are discussed.

Keywords: creativity, expertise , education, technology

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7827 New Hybrid Method to Model Extreme Rainfalls

Authors: Youness Laaroussi, Zine Elabidine Guennoun, Amine Amar

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Modeling and forecasting dynamics of rainfall occurrences constitute one of the major topics, which have been largely treated by statisticians, hydrologists, climatologists and many other groups of scientists. In the same issue, we propose in the present paper a new hybrid method, which combines Extreme Values and fractal theories. We illustrate the use of our methodology for transformed Emberger Index series, constructed basing on data recorded in Oujda (Morocco). The index is treated at first by Peaks Over Threshold (POT) approach, to identify excess observations over an optimal threshold u. In the second step, we consider the resulting excess as a fractal object included in one dimensional space of time. We identify fractal dimension by the box counting. We discuss the prospect descriptions of rainfall data sets under Generalized Pareto Distribution, assured by Extreme Values Theory (EVT). We show that, despite of the appropriateness of return periods given by POT approach, the introduction of fractal dimension provides accurate interpretation results, which can ameliorate apprehension of rainfall occurrences.

Keywords: extreme values theory, fractals dimensions, peaks Over threshold, rainfall occurrences

Procedia PDF Downloads 361
7826 An Insight Into the Effective Distribution of Lineaments Over Sheared Terrains to Hydraulically Characterize the Shear Zones in Hard Rock Aquifer System

Authors: Tamal Sur, Tapas Acharya

Abstract:

Identifying the water resource in hard crystalline rock terrain has been a huge challenge over the decades as it is considered a poor groundwater province area. Over the years, usage of satellite imagery for the delineation of groundwater potential zone in sheared hard rock terrain has been occasionally successful. In numerous circumstances, it has been observed that groundwater potential zone delineated by satellite imagery study has failed to yield satisfactory result on its own. The present study discusses the fact that zones having a high concentration of lineaments oblique to the general trend of shear fabric could be good groundwater potential zones within a shear zone in crystalline fractured rock aquifer system. Due to this fact, the density of lineaments and the number of intersecting lineaments increases over that particular region, making it a suitable locale for good groundwater recharge, which is mostly composed of Precambrian metamorphic rocks i.e., quartzite, granite gneisses, porphyroclastic granite-gneiss, quartzo-feldspathic-granite-gneiss, mylonitic granites, quartz-biotite-granite gneiss and some phyllites of Purulia district of West Bengal, NE India. This study aims to construct an attempt to demonstrate the relationship of the high amount of lineament accumulation and their intersection with high groundwater fluctuation zones, i.e., good groundwater potential zones. On the basis of that, an effort has been made to characterize the shear zones with respect to their groundwater potentiality. Satellite imagery data (IRS-P6 LISS IV standard FCC image) analysis reveals the bifurcating nature of North Purulia shear zone (NPSZ) and South Purulia shear zone (SPSZ) over the study area. Careful analysis of lineament rose diagrams, lineament density map, lineament intersection density map, and frequency diagrams for water table depths with an emphasis on high water table fluctuations exhibit the fact that different structural features existing over North and South Purulia shear zones can affect the nature of hydraulic potential of that region.

Keywords: crystalline hard rock terrain, groundwater recharge, hydrogeology, lineaments, shear zone, water table fluctuation

Procedia PDF Downloads 87
7825 Kant’s Conception of Human Dignity and the Importance of Singularity within Commonality

Authors: Francisco Lobo

Abstract:

Kant’s household theory of human dignity as a common feature of all rational beings is the starting point of any intellectual endeavor to unravel the implications of this normative notion. Yet, it is incomplete, as it neglects considering the importance of the singularity or uniqueness of the individual. In a first, deconstructive stage, this paper describes the Kantian account of human dignity as one among many conceptions of human dignity. It reads carefully into the original wording used by Kant in German and its English translations, as well as the works of modern commentators, to identify its shortcomings. In a second, constructive stage, it then draws on the theories of Aristotle, Alexis de Tocqueville, John Stuart Mill, and Hannah Arendt to try and enhance the Kantian conception, in the sense that these authors give major importance to the singularity of the individual. The Kantian theory can be perfected by including elements from the works of these authors, while at the same time being mindful of the dangers entailed in focusing too much on singularity. The conclusion of this paper is that the Kantian conception of human dignity can be enhanced if it acknowledges that not only morality has dignity, but also the irreplaceable human individual to the extent that she is a narrative, original creature with the potential to act morally.

Keywords: commonality, dignity, Kant, singularity

Procedia PDF Downloads 284
7824 Conceptual Metaphors of Responsibility in Arabic to English Translation of Political Speeches: A Corpus-Based Study

Authors: Amr Anany

Abstract:

This study offers a corpus-based analysis of the conceptual metaphors of RESPONSIBILITY inherent in the Arabic political speeches of King Abdulla II and their English translations rendered by the translators of the Royal Hashemite Court ("RHC translators"). In view of the Conceptual Metaphor Theory (CMT), the current study aims to uncover the extent to which the dominant ideology in the source Arabic speeches of King Abdulla II is conveyed into the target English translation. The study explores a bilingual corpus, including eleven authentic Arabic speeches delivered by King Abdulla II and their English translations. The study finds that both Arabic and English share several metaphorical expressions of RESPONSIBILITY that are based on bodily experience such as RESPONSIBILITY IS UP, RESPONSIBILITY IS AN OBJECT, and RESPONSIBILITY IS AN HONOR. Apparently, the study concludes that RHC translators succeed to convey the dominant ideology from the source Arabic speeches to the English ones using specific translation strategies.

Keywords: cognitive linguistics, CDA, conceptual metaphor theory, ideology, responsibility

Procedia PDF Downloads 71
7823 Developmental Social Work: A Derailed Post-Apartheid Development Approach in South Africa

Authors: P. Mbecke

Abstract:

Developmental social welfare implemented through developmental social work is being applauded internationally as an approach that facilitates social development theory and practice. However, twenty-two years into democracy, there are no tangible evidences that the much-desired developmental social welfare approach has assisted the post-apartheid macroeconomic policy frameworks in addressing poverty and inequality, thus, the derailment of the post-apartheid development approach in South Africa. Based on the implementation research theory, and the literature review technique, this paper recognizes social work as a principal role-player in social development. It recommends the redesign and implementation of an effective developmental social welfare approach with specific strategies, programs, activities and sufficient resources aligned to and appropriate in delivering on the promises of the government’s macroeconomic policy frameworks. Such approach should be implemented by skilled and dedicated developmental social workers in order to achieve transformation in South Africa.

Keywords: apartheid, developmental social welfare, developmental social work, inequality, poverty alleviation, social development, South Africa

Procedia PDF Downloads 366
7822 Autonomic Nervous System Changes Associated with Rheumatoid Arthritis: Clinical and Electrophysiological Study

Authors: Emmanuel Kamal Aziz Saba, Hussein Al-Moghazy Sultan

Abstract:

The aim of this study was to evaluate clinically and electro physiologically the autonomic nervous system changes associated with rheumatoid arthritis (RA). The present study included 25 patients with RA [22 women (88%)] and 30 apparently healthy control subjects [27 women (90%)]. A thorough clinical examination was carried out. Disease activity and functional disability were assessed. Tests for assessment of autonomic functions include active and passive orthostatic stress tests, and sympathetic skin response (SSR). The presence of abnormality in 2 tests or more was a clue for the presence of autonomic neuropathy (AN). Sural sensory nerve conduction study and posterior tibial motor nerve conduction study were done. There was a statistically significant decrease in standing systolic and diastolic blood pressure (BP) components of the active orthostatic stress test and SSR amplitude as well as statistically significant prolongation of SSR latency of RA patients when compared to control. Three patients (12%) had clinical symptoms suggestive of AN; increased to 14 patients (56 %) when orthostatic stress tests and SSR were utilized. There were no statistically significant differences between patients with different disease activity score 28 with 4 variables grades of RA activity and SSR latency and amplitude. There were no statistically significant differences between patients with different Stanford Health Assessment Questionnaire Disability Index grades of RA functional disability and SSR latency and amplitude. In conclusion, autonomic neuropathy is a common extra-articular manifestation of RA affecting sympathetic and parasympathetic fibers.

Keywords: autonomic neuropathy, orthostatic stress test, rheumatoid arthritis, sympathetic skin response

Procedia PDF Downloads 359
7821 Clinical and Radiological Outcome in 300 Patients with Non-Aneurysmal Sah

Authors: Ranjith Menon, Abathar Aladi, Hans-Christean Nahser, Maneesh Bhojak, Sacha Nevin, Paul Eldridge

Abstract:

Background: Spontaneous subarachnoid haemorrhage (SAH) accounts for approximately 5% of all strokes. Patients with spontaneous SAH (as shown by CT or lumbar puncture) undergo investigations to identify or exclude an underlying structural cause, typically cerebral aneurysm. However in 10 - 20% of cases, no structural cause is found. This includes more than one imaging modality (intracranial MRA, CTA, 4DCTA and/or DSA) and in some spinal MRI. Objective: To determine; 1) If an underlying structural or vascular cause can be identified in non-aneurysmal SAH patients by comparing different imaging modalities at presentation and at follow-up. 2) If MRI spine in patients with non-aneurysmal SAH reveals an underlying SAH cause. 3)The functional outcome at discharge. Results: We performed a retrospective analysis of all non-traumatic SAH patients admitted to the Walton centre from January 2009 to December 2015. There were 1457 patients with non-traumatic SAH admitted to the Walton centre of whom 21.8% (n=300) patients were diagnosed with non-aneurysmal SAH. Males were 65.6% and females were 43.3%. The presenting symptoms were sudden onset headache (93.6%), the focal neurological deficit (12%), loss of consciousness (10.6%) and others (6%). About 285 patients received 2 modalities of imaging (CTA & DSA), 192 received 3 modalities of imaging (CTA, MRA & DSA) and 137 received MRI spine (51/137 whole spine). The modified Rankin Score at discharge were: mRS 0 = 292 (97.33%), mRS 1-2 = 6, mRS 6 = 1 (cardiac arrest in IHD patient) and unknown in 1. Follow-up imaging at 3 to 6 months in 190 (63.3%) patients did not identify an underlying cause. Conclusion: This retrospective analysis concludes that non-aneurysmal SAH has a good functional outcome. A single imaging modality (CTA (4DCTA) or MRA or DSA) was adequate to exclude an underlying cause of SAH and a delayed imaging failed to identify a cause. Routinely performing MRI spine in this group of patients appears not to be necessary according to this evidence.

Keywords: stroke, non-aneurysmal subarachnoid haemorrhage, neuroimaging, modified rankin score

Procedia PDF Downloads 268
7820 An Insight into the Distribution of Lineaments over Sheared Terrains to Hydraulically Characterize the Shear Zones in Precambrian Hard Rock Aquifer System

Authors: Tamal Sur, Tapas Acharya

Abstract:

Identifying the water resource in hard crystalline rock terrain has been a huge challenge over the decades as it is considered a poor groundwater province area. Over the years, usage of satellite imagery for the delineation of groundwater potential zone in sheared hard rock terrain has been occasionally successful. In numerous circumstances, it has been observed that groundwater potential zone delineated by satellite imagery study has failed to yield satisfactory result on its own. The present study discusses the fact that zones having high concentration of lineaments oblique to the general trend of shear fabric could be good groundwater potential zones within a shear zone in crystalline fractured rock aquifer system. Due to this fact, the density of lineaments and the number of intersecting lineaments increases over that particular region, making it a suitable locale for good groundwater recharge, which is mostly composed of Precambrian metamorphic rocks i.e., quartzite, granite gneisses, porphyroclastic granite-gneiss, quartzo-feldspathic-granite-gneiss, mylonitic granites, quartz-biotite-granite gneiss and some phyllites of Purulia district of West Bengal, NE India. This study aims to construct an attempt to demonstrate the relationship of high amount of lineament accumulation and their intersection with high groundwater fluctuation zones i.e., good groundwater potential zones. On the basis of that, an effort has been made to characterize the shear zones with respect to their groundwater potentiality. Satellite imagery data (IRS-P6 LISS IV standard FCC image) analysis reveals the bifurcating nature of North Purulia shear zone (NPSZ) and South Purulia shear zone (SPSZ) over the study area. Careful analysis of lineament rose diagrams, lineament density map, lineament intersection density map, and frequency diagrams for water table depths with an emphasis on high water table fluctuations exhibit the fact that different structural features existing over North and South Purulia shear zones can affect the nature of hydraulic potential of that region.

Keywords: crystalline hard rock terrain, groundwater recharge, hydrogeology, lineaments, shear zone, water table fluctuation

Procedia PDF Downloads 78
7819 Nonlinear Modelling and Analysis of Piezoelectric Smart Thin-Walled Structures in Supersonic Flow

Authors: Shu-Yang Zhang, Shun-Qi Zhang, Zhan-Xi Wang, Xian-Sheng Qin

Abstract:

Thin-walled structures are used more and more widely in modern aircrafts and some other structures in aerospace field nowadays. Accompanied by the wider applications, the vibration of the structures has been a bigger problem. Because of the direct and converse piezoelectric effect, piezoelectric materials combined to host thin-walled structures, named as piezoelectric smart structures, can be an effective way to suppress the vibration. So, an accurate model for piezoelectric thin-walled structures in air flow is necessary and important. In our recent work, an electromechanical coupling nonlinear aerodynamic finite element model of piezoelectric smart thin-walled structures is built based on the Reissner-Mindlin plate theory and first-order piston theory for aerodynamic pressure of supersonic flow. Von Kármán type nonlinearity is considered in the present model. Finally, the model is validated by experimental and numerical results from the literature, which can describe the vibration of the structures in supersonic flow precisely.

Keywords: piezoelectric smart structures, aerodynamic, geometric nonlinearity, finite element analysis

Procedia PDF Downloads 389
7818 Effect of Concurrent Training and Detraining on Insulin Resistance in Obese Children

Authors: Kaveh Azadeh, Saeid Fazelifar

Abstract:

The main purpose of the present study was to examine the effect of 12 weeks (3 days/week) concurrent training followed by 4 weeks detraining on insulin resistance in obese boys without dietary intervention. Methods: 24 obese children boys (body mass index> 28, age= 11- 13year old) voluntarily participated in the study. Biochemical factors, body composition, and functional physical fitness were assessed in three stages [baseline, after 12 week’s combined endurance and resistance training and 4 week’s detraining in the experimental group (n=12); baseline and after 12 weeks in control group (n=12)]. Results: Indepented - Sample T test revealed that in experimental group after 12weeks trainings the insulin resistance, and body fat mass were significantly declined, whereas endurance and strength of abdominal muscles significantly increased compared to control group (p<0/05). One-way ANOVA for three different periods showed that insulin resistance, body fat mass, strength of abdominal muscles after 12week training was significantly improved in the experimental group compared with the baseline. Following 4weeks detraining insulin resistance again significantly increased (p<0/05). After detraining disturbances of physiological adaptation in obese children have more rapid course in comparison with those anthropological and functional indices. Conclusion: Results showed that participation in the regular concurrent trainings provides a decrease of insulin resistance in obese children. It may serve as a strategy in treatment of obesity and management on insulin resistance, as well as to increase endurance and strength muscles in obese children. Adaptations resulting from regular exercises following detraining are reversible.

Keywords: endurance and resistance trainings, detraining, insulin resistance, obese children

Procedia PDF Downloads 195
7817 Self-Marketing on Line Person-to-Person Social Media

Authors: Chih-Ping Chen

Abstract:

Today, technology does not necessitate change; rather, social media has afforded a new arena and digital tools for users/individuals to be symbolized and marketed in meaningful exchanges of digital identities. We argue that these symbolic interactions may afford individuals the ability to create and present less restricted Line person-to-person (P2P) chats than would be possible in face-to-face communications. Individuals can select flexible influence strategies to market themselves, which enables them to create and present their digital identities and impressions in alternative ways within a dynamic sociocultural context. Therefore, this paper aims to explore the novel phenomenon of how individuals market themselves to manage their digital identities and impressions to connect with other users through the symbolic interactions created by new digital tools (e.g., stickers). A netnographic approach was developed by applying a triangulated methodology consisting of user self-diary reports, in-depth interviews, and observations. Totally, 20 participants (10 females and 10 males) were of Taiwanese origin, and their ages ranged from 20–47 years old. The findings of this research showed that individuals on Line P2P social media where traditional cultural gender norms have shifted. Both male and female participants market their modern digital identities by adopting a combination of flexible influence tactics/strategies when using digital stickers. Some findings showed that their influence tactics/strategies often flouted Taiwanese cultural gender norms or skirted traditional rules to fit individual or P2P needs. Finally, these findings potentially contributed to the literature regarding the consumer culture theory and symbolic interaction theory in digital marketing and social media fields.

Keywords: Consumer culture theory, Digital sticker, Self-marketing, Impression, Symbolic interaciton

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7816 Comparison of Bone Mineral Density of Lumbar Spines between High Level Cyclists and Sedentary

Authors: Mohammad Shabani

Abstract:

The physical activities depending on the nature of the mechanical stresses they induce on bone sometimes have brought about different results. The purpose of this study was to compare bone mineral density (BMD) of the lumbar spine between the high-level cyclists and sedentary. Materials and Methods: In the present study, 73 cyclists senior (age: 25.81 ± 4.35 years; height: 179.66 ± 6.31 cm; weight: 71.55 ± 6.31 kg) and 32 sedentary subjects (age: 28.28 ± 4.52 years; height: 176.56 ± 6.2 cm; weight: 74.47 ± 8.35 kg) participated voluntarily. All cyclists belonged to the different teams from the International Cycling Union and they trained competitively for 10 years. BMD of the lumbar spine of the subjects was measured using DXA X-ray (Lunar). Descriptive statistics calculations were performed using computer software data processing (Statview 5, SAS Institute Inc. USA). The comparison of two independent distributions (BMD high level cyclists and sedentary) was made by the Student T Test standard. Probability 0.05 (p≤0 / 05) was adopted as significance. Results: The result of this study showed that the BMD values of the lumbar spine of sedentary subjects were significantly higher for all measured segments. Conclusion and Discussion: Cycling is firstly a common sport and on the other hand endurance sport. It is now accepted that weight bearing exercises have an osteogenic effect compared to non-weight bearing exercises. Thus, endurance sports such as cycling, compared to the activities imposing intense force in short time, seem not to really be osteogenic. Therefore, it can be concluded that cycling provides low stimulates osteogenic because of specific biomechanical forces of the sport and its lack of impact.

Keywords: BMD, lumbar spine, high level cyclist, cycling

Procedia PDF Downloads 269
7815 Designing ZIF67 Derivatives Using Ammonia-Based Fluorine Complex as Structure-Directing Agent for Energy Storage Applications

Authors: Lu-Yin Lin

Abstract:

The morphology of electroactive material is highly related to energy storage ability. Structure-directing agent (SDA) can design electroactive materials with favorable surface properties. Zeolitic imidazolate framework 67 (ZIF67) is one of the potential electroactive materials for energy storage devices. The SDA concept is less applied to designing ZIF67 derivatives in previous studies. An in-situ technique with ammonium fluoride (NH₄F) as SDA is proposed to produce a ZIF67 derivative with highly improved energy storage ability. Attracted by the effective in-situ technique, the NH₄F, ammonium bifluoride (NH₄HF₂), and ammonium tetrafluoroborate (NH₄BF₄) are first used as SDA to synthesize ZIF67 derivatives in one-step solution process as electroactive material of energy storage devices. The mechanisms of forming ZIF67 derivatives synthesized with different SDAs are discussed to explain the SDA effects on physical and electrochemical properties. The largest specific capacitance (CF) of 1527.0 Fg-¹ and the capacity of 296.9 mAhg-¹ are obtained for the ZIF67 derivative prepared using NH₄BF₄ as SDA. The energy storage device composed of the optimal ZIF67 derivative and carbon electrodes presents a maximum energy density of 15.1 Whkg-¹ at the power density of 857 Wkg-¹. The CF retention of 90% and Coulombic efficiency larger than 98% are also obtained after 5000 cycles.

Keywords: ammonium bifluoride, ammonium tetrafluoroborate, energy storage device, one-step solution process, structure-directing agent, zeolitic imidazolate framework 67

Procedia PDF Downloads 79