Search results for: micro polypropylene fibers

Authors: Ricardo Mendoza, Jason Briceño, Juan F. Santa, Gabriel Peluffo, Mauricio Márquez, Beatriz Cardozo, Carlos Gutiérrez

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The most common controlled method to obtain impact strength of composites materials is performing a Charpy Impact Test which consists of a pendulum with calibrated mass and length released from a known height. In fact, composites components experience impact events in normal operations such as when a tool drops or a foreign object strikes it. These events are categorized into low velocity impact (LVI) which typically occurs at velocities below 10m/s. In this study, the major aim was to calculate the absorbed energy during the impact. Tests were performed on three types of composite panels: fiberglass laminated panels, coir fiber reinforced polyester and coir fiber reinforced polyester subjected to water immersion for 48 hours. Coir fibers were obtained in local plantations of the Caribbean coast of Colombia. They were alkali treated in 5% aqueous NaOH solution for 2h periods. Three type of shape impactors were used on drop-weight impact test including hemispherical, ogive and pointed. Failure mechanisms and failure modes of specimens were examined using an optical microscope. Results demonstrate a reduction in absorbed energy correlated with the increment of water absorption of the panels. For each level of absorbed energy, it was possible to associate a different fracture state. This study compares results of energy absorbed obtained from two impact test methods.

Keywords: coir fiber, polyester composites, low velocity impact, Charpy impact test, drop-weight impact test

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Authors: Ming-Wei Wu, Yu-Jin Tsai, Ching-Huai Chang

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Liquid phase sintering (LPS) is a versatile technique for achieving effective densification of powder metallurgy (PM) steels and other materials. The aim of this study was to examine the influences of 0.6 wt% boron on the microstructure and LPS behavior of boron-alloyed 410 martensitic stainless steel. The results showed that adding 0.6 wt% boron can obviously promote the LPS due to a eutectic reaction and increase the sintered density of 410 stainless steel. The density was much increased by 1.06 g/cm³ after 1225ºC sintering. Increasing the sintering temperature from 1225ºC to 1275ºC did not obviously improve the sintered density. After sintering at 1225ºC~1275ºC, the matrix was fully martensitic, and intragranular borides were extensively found due to the solidification of eutectic liquid. The microstructure after LPS consisted of the martensitic matrix and (Fe, Cr)2B boride, as identified by electron backscatter diffraction (EBSD) and electron probe micro-analysis (EPMA).

Keywords: powder metallurgy, liquid phase sintering, stainless steel, martensite, boron, microstructure

Procedia PDF Downloads 254

Authors: Dechrit Maneetham

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The aim of this paper was to design a smart electric power wheelchair (SEPW) with a novel control system for quadriplegics with head and neck mobility. Head movement has been used as a control interface for people with motor impairments in a range of applications. Acquiring measurements from the module is simplified through a synchronous a motor. Axis measures the two directions namely X ,Y and Z. The model of a DC motor is considered as a speed control by selection of a PID parameters using genetic algorithm. An experimental set-up constructed, which consists of micro controller Arduino ATmega32u4 as controllers, a DC motor driven SEPW and feedback elements. And this paper is tuning methods of parameter for a pulse width modulation (PWM) control system. A speed controller has been designed successfully for closed loop of the DC motor so that the motor runs very closed to the reference speed and angle. SEPW controller can be used to ensure the person’s head is attending the direction of travel asserted by a conventional, direction and speed control.

Keywords: wheelchair, quadriplegia, rehabilitation, medical devices, speed control

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Authors: M. E. Semenov, U. Zh. Mirzakimov, A. S. Stoporev, R. S. Pavelev, M. A. Varfolomeev

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Gas hydrates are host-guest compounds. Guest molecules can be low molecular weight components of associated petroleum gas (C1-C4 hydrocarbons), carbon dioxide, hydrogen sulfide, and nitrogen. Gas hydrates have a number of unique properties that make them interesting from a technological point of view, for example, for storing hydrocarbon gases in solid form under moderate thermobaric conditions. Currently, the possibility of storing and transporting hydrocarbon gases in the form of solid hydrate is being actively explored throughout the world. The hydrate form of gas has a number of advantages, including a significant gas content in the hydrate, relative safety and environmental friendliness of the process. Recently, new developments have been proposed that seek to reduce the number of steps to obtain the finished hydrate, for example, using a pressing device/screw inside the reactor. However, the energy consumption required for the hydrate formation process remains a challenge. Thus, the goal of the current work is to study the patterns and mechanisms of the hydrate formation process using small additions of hydrate formation promoters under static conditions. The study of these aspects will help solve the problem of accelerated production of gas hydrates with minimal energy consumption. New compounds have been developed at Kazan Federal University that can accelerate the formation of methane hydrate with a small amount of promoter in water, not exceeding 0.1% by weight. These promoters were synthesized based on available natural compounds and showed high efficiency in accelerating the growth of methane hydrate. To test the influence of promoters on the process of hydrate formation, standard experiments are carried out under dynamic conditions with stirring. During such experiments, the time at which hydrate formation begins (induction period), the temperature at which formation begins (supercooling), the rate of hydrate formation, and the degree of conversion of water to hydrate are assessed. This approach helps to determine the most effective compound in comparative experiments with different promoters and select their optimal concentration. These experimental studies made it possible to study the features of the formation of associated petroleum gas hydrate from promoter solutions under static conditions. Phase transformations were studied using high-pressure micro-differential scanning calorimetry under various experimental conditions. Visual studies of the growth mode of methane hydrate depending on the type of promoter were also carried out. The work is an extension of the methodology for studying the effect of promoters on the process of associated petroleum gas hydrate formation in order to identify new ways to accelerate the formation of gas hydrates without the use of mixing. This work presents the results of a study of the process of associated petroleum gas hydrate formation using high-pressure differential scanning micro-calorimetry, visual investigation, gas chromatography, autoclaves study, and stability data. It was found that the synthesized compounds multiply the conversion of water into hydrate under static conditions up to 96% due to a change in the growth mechanism of associated petroleum gas hydrate.

Keywords: gas hydrate, gas storage, promotor, associated petroleum gas

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Authors: Morteza Habibi, Reza Amrollahi

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The Aluminum made targets were placed at the central part of a Fillipov type (90KJ) plasma focus cathode. These targets were exposed to perpendicular dense plasma stream incidence. Melt layer erosion by melt motion, surface smoothing, and bubble formation were some of different effects caused by diverse working conditions. Micro hardness of surface layer tends to decrease particularly in the central region of the sample where destruction is more intense. The most pronouced melt motion is registered in the region of the maximum gradient of pressure and the etching of aluminium surface is noticeable in the central part of target. The crater with a maximum depth of 200µm, and the diameter of about 8.5mm is observed close to the mountains. Adding Krypton admixture to the Deuterium gas lead to collapsing bubbles and greater surface damage.

Keywords: fillipov type plasma focus, al target interaction, bubbling effect, melt layer motion, surface smoothing

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Authors: Shuyi Wu, Chuang Li, Quanshui Zheng, Luping Xu

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Stretching and snipping DNA molecule by microfluidic has important application value in gene analysis by lab on a chip. Movement, deformation and fragmenting of DNA in microfluidic are typical fluid-solid coupling problems. An efficient and common simulation system for researching the movement, deformation and fragmenting of DNA by microfluidic has not been well developed. In our study, Brownian dynamics-finite element method (BD-FEM) is used to simulate the dynamic process of stretching and fragmenting DNA by contraction flow. The shape and parameters of micro-channels are changed to optimize the stretching and fragmenting properties of DNA. Our results indicate that strain rate, resulting from contraction microchannel, is the main control parameter for stretching and fragmenting DNA. There is good consistency between the simulation data and previous experimental result about the single DNA molecule behavior and averaged fragmenting properties in this study. BD-FEM method is an efficient calculating tool to research stretching and fragmenting behavior of single DNA molecule and optimize microfluidic devices for manipulating, stretching and fragmenting DNA.

Keywords: fragmenting, DNA, microfluidic, optimize.

Procedia PDF Downloads 320

Authors: Salah Aguib, Noureddine Chikh, Abdelmalek Khabli, Abdelkader Nour, Toufik Djedid, Lallia Kobzili

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This study presents the behavior of a hybrid smart sandwich plate with a magnetorheological elastomer core. In order to improve the vibrational behavior of the plate, the pseudo‐fibers formed by the effect of the magnetic field on the elastomer charged by the ferromagnetic particles are oriented at 45° with respect to the direction of the magnetic field at 0°. Ritz's approach is taken to solve the physical problem. In order to verify and compare the results obtained by the Ritz approach, an analysis using the finite element method was carried out. The rheological property of the MRE material at 0° and at 45° are determined experimentally, The studied elastomer is prepared by a mixture of silicone oil, RTV141A polymer, and 30% of iron particles of total mixture, the mixture obtained is mixed for about 15 minutes to obtain an elastomer paste with good homogenization. In order to develop a magnetorheological elastomer (MRE), this paste is injected into an aluminum mold and subjected to a magnetic field. In our work, we have chosen an ideal percentage of filling of 30%, to obtain the best characteristics of the MRE. The mechanical characteristics obtained by dynamic mechanical viscoanalyzer (DMA) are used in the two numerical approaches. The natural frequencies and the modal damping of the sandwich plate are calculated and discussed for various magnetic field intensities. The results obtained by the two methods are compared. These off‐axis anisotropic MRE structures could open up new opportunities in various fields of aeronautics, aerospace, mechanical engineering and civil engineering.

Keywords: hybrid smart sandwich plate, vibratory behavior, FEM, Ritz approach, MRE

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Authors: N. Moudir, N. Moulai-Mostefa, Y. Boukennous, I. Bozetine, N. Kamel, D. Moudir

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the study focuses on a novel process of silver powders synthesis for the preparation of conductive pastes used for solar cells metalization. Butyl-Carbitol and butyl-carbitol Acetate have been used as solvents and reducing agents of silver nitrate (AgNO3) as precursor to get silver powders. XRD characterization revealed silver powders with a cubic crystal system. SEM micro graphs showed spherical morphology of the particles. Laser granulometer gives similar particles distribution for the two agents. Using same glass frit and organic vehicle for comparative purposes, two conductive pastes were prepared with the synthesized silver powders for the front-side metalization of multi-crystalline cells. The pastes provided acceptable fill factor of 59.5 % and 60.8 % respectively.

Keywords: chemical reduction, conductive paste, silver nitrate, solar cell

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Authors: Mohd Yussni Hashim, Mohd Nazrul Roslan, Shahruddin Mahzan Mohd Zin, Saparudin Ariffin

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Fiber cross-sectional area value is a crucial factor in determining the strength properties of natural fiber. Furthermore, unlike synthetic fiber, a diameter and cross-sectional area of natural fiber has a large variation along and between the fibers. This study aims to determine the main and interaction effects of alkali treatment conditions that influence kenaf bast fiber mean cross-sectional area. Three alkali treatment conditions at two different levels were selected. The conditions setting were alkali concentrations at two and ten w/v %; fiber immersed temperature at room temperature and 1000C; and fiber immersed duration for 30 and 480 minute. Untreated kenaf fiber was used as a control unit. Kenaf bast fiber bundle mounting tab was prepared according to ASTM C1557-03. The cross-sectional area was measured using a Leica video analyzer. The study result showed that kenaf fiber bundle mean cross-sectional area was reduced 6.77% to 29.88% after alkali treatment. From the analysis of variance, it shows that the interaction of alkali concentration and immersed time has a higher magnitude at 0.1619 compared to alkali concentration and immersed temperature interaction that was 0.0896. For the main effect, alkali concentration factor contributes to the higher magnitude at 0.1372 which indicated the decrease pattern of variability when the level changed from lower to the higher level. Then, it was followed by immersed temperature at 0.1261 and immersed time at 0.0696 magnitudes.

Keywords: natural fiber, kenaf bast fiber bundles, alkali treatment, cross-sectional area

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Authors: Abdoullah Namdar, Fadzil Mat Yahaya

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The waste agriculture materials cause environment pollution, recycle of these materials help sustainable development. This study focused on the impact of used oil palm shell ash on the compressive and flexural strengths of cement mortar. Two different cement mortar mixes have been designed to investigate the impact of oil palm shell ash on strengths of cement mortar. Quantity of 4% oil palm shell ash has been replaced in cement mortar. The main objective of this paper is, to modify mechanical properties of cement mortar by replacement of oil palm ash in it at early age of seven days. The results have been revealed optimum quantity of oil palm ash for replacement in cement mortar. The deflection, load to failure, time to failure of compressive strength and flexural strength of all specimens have significantly been improved. The stress-strain behavior has been indicated ability of modified cement mortar in control stress path and strain. The micro property of cement paste has not been investigated.

Keywords: minerals, additive, flexural strength, compressive strength, modulus of elasticity

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Authors: Zhidong Zhang, Zhi-Chao Zhang

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This study examines adolescent psychological and behavioral problems. The Achenbach systems of empirically based assessment (ASEBA) were used as the instrument. The problem framework consists of internal, external and social behavioral problems which are theoretically developed based on about 113 items plus relevant background variables. In this study, the sample consist of 1,975 sixth and seventh grade students in Northeast China. Stratified random sampling method was used to collect the data, meaning that samples were from different school districts, schools, and classes. The researchers looked at both macro and micro effect. Therefore, multilevel analysis techniques were used in the data analysis. The parts of the research results indicated that the background variables such as extracurricular activities were directly related to students’ internal problems.

Keywords: behavioral problems, anxious/depressed problems, internalizing problems, mental health, under-represented groups, empirically-based assessment, hierarchical modeling, ASEBA, multilevel analysis

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Authors: Adrian Travieso Disotuar, J. Antonio Travieso Rodriguez, Ramon Jerez Mesa, Montserrat Vilaseca

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The effect of the non-vibration-assisted and vibration-assisted ball burnishing on both the surface and mechanical properties of C300 obtained by Selective Laser Melting additive manufacturing technology is studied in this paper. Different vibration amplitudes preloads, and burnishing strategies were tested. A topographical analysis was performed to determine the surface roughness of the different conditions. Besides, micro tensile tests were carried out in situ on Scanning Electron Microscopy to elucidate the post-treatment effects on damaging mechanisms. Experiments show that vibration-assisted ball burnishing significantly enhances mechanical properties compared to the non-vibration-assisted method. Moreover, it was found that the surface roughness was significantly improved with respect to the reference surface.

Keywords: additive manufacturing, ball burnishing, mechanical properties, metals, surface roughness

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Authors: Ashkan Vatani, Petere Woodfiel, Nam-Trung Nguyen, Dzung Dao

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Thermomagnetic convection of a ferrofluid flow induced by the non-uniform magnetic field around a current-carrying wire was theoretically analyzed, numerically studied and experimentally validated. The dependency of the thermomagnetic convection on the current and fluid temperature has been studied. The Nusselt number for a heated 50um diameter wire in the ferrofluid exponentially scales with applied current to the micro-wire. This result is in good agreement with the correlated Nusselt number by curve-fitting the experimental data at different fluid temperatures. It was shown that at low currents, no significance is observed for thermomagnetic convection rather than the buoyancy-driven convection, while the thermomagnetic convection becomes dominant at high currents. Also, numerical simulations showed a promising cooling ability for large scale applications.

Keywords: ferrofluid, non-uniform magnetic field, Nusselt number, thermomagnetic convection

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Authors: Artur Krukowski, Emmanouela Vogiatzaki

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The article presents results from the AF3 project “Advanced Forest Fire Fighting” focused on Unmanned Aircraft Systems (UAS)-based 3D surveillance and 3D area mapping using high-resolution photogrammetric methods from multispectral imaging, also taking advantage of the 3D scanning techniques from the SCAN4RECO project. We also present a proprietary embedded sensor system used for the detection of fire ignitions in the forest using near-infrared based scanner with weight and form factors allowing it to be easily deployed on standard commercial micro-UAVs, such as DJI Inspire or Mavic. Results from real-life pilot trials in Greece, Spain, and Israel demonstrated added-value in the use of UAS for precise and reliable detection of forest fires, as well as high-resolution 3D aerial modeling for accurate quantification of human resources and equipment required for firefighting.

Keywords: forest wildfires, surveillance, fuel volume estimation, firefighting, ignition detectors, 3D modelling, UAV

Procedia PDF Downloads 137

Authors: C. Busuioc, G. Voicu, S. I. Jinga

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The field of tissue engineering brings new challenges in terms of proposing original solutions for ongoing medical issues, improving the biological performances of existing clinical systems and speeding the healing process for a faster recovery and a more comfortable life as patient. In this context, we propose the obtaining of 3D porous scaffolds of mineral nature, dedicated to bone repairing and regeneration purposes or employed as bioactive filler for bone cements. Thus, bacterial cellulose - calcium phosphates composite materials have been synthesized by successive immersing of the polymeric membranes in the precursor solution containing Ca2+ and [PO4]3- ions. The mineral phase deposited on the surface of biocellulose fibers was varied as amount through the number of immersing cycles. The intermediary composites were subjected to thermal treatments at different temperatures in order to remove the organic part and provide the formation of a self-sustained 3D architecture. The resulting phase composition consists of common phosphates, while the morphology largely depends on the preparation parameters. Thus, the aspect of the 3D mineral scaffolds can be tuned from a loose microstructure composed of large grains connected via monocrystalline nanorods to a trabecular pattern crossed by parallel internal channels, just like the natural bone. The bioactivity and biocompatibility of the obtained materials have been also assessed, with encouraging results in the clinical use direction. In conclusion, the compositional, structural, morphological and biological characterizations sustain the suitability of the reported biostructures for integration in hard tissue engineering applications.

Keywords: bacterial cellulose, bone reconstruction, calcium phosphates, mineral scaffolds

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Authors: Manikandan Sathianarayanan, Pernaidu Pasala

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This paper presents the results of our studies concerning the implementation and exploitation of a Geographical Information System (GIS) dedicated to the support and assistance of decisions requested by drought management. In this study on diverting of surplus water through canals, pond sand check dams in the study area was carried out. The remote sensing data and GIS data was used to identify the drought prone villages in sivaganga taluk and to generate present land use, drainage pattern as well as slope and contour. This analysis was carried out for diverting surplus water through proposed canal and pond. The results of the study indicate that if the surplus water from the ponds and streams are diverted to the drought villages in Sivaganga taluk, it will definitely improve the agricultural production due to availability of water in the ponds. The improvements in agricultural production will help to improve the economical condition of the farmers in the region.

Keywords: interlinking, spatial analysis, remote sensing, GIS

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Authors: M. Alsaadi, A. Erkliğ, M. Bulut

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This paper experimentally investigates the flexural and tensile properties of the industrial wastes sewage sludge ash (SSA) and fly ash (FA), and conventional ceramic powder silicon carbide (SiC) filled polyester composites. Four weight fractions (5, 10, 15 and 20 wt%) for each micro filler were used for production of composites. Then, test samples were produced according to ASTM. The resulting degree of particle dispersion in the polymer matrix was visualized by using scanning electron microscope (SEM). Results from this study showed that the tensile strength increased up to its maximum value at filler content 5 wt% of SSA, FA and SiC. Flexural strength increased with addition of particulate filler up to its maximum value at filler content 5 wt% of SSA and FA while for SiC decreased for all weight fractions gradually. The addition of SSA, FA and SiC fillers resulted in increase of tensile and flexural modulus for all the particulate composites. Industrial waste SSA can be used as an additive with polymer to produce composite materials.

Keywords: particle-reinforcement, sewage sludge ash, polymer matrix composites, mechanical properties

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Authors: Ndidi F. Amulu, Calistus N. Ude, Patrick E. Amulu, Nneka N. Uchegbu

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The effects of temperature and enzyme concentration on the quality of mixed pineapple and pawpaw blended fruits juice were studied. Extracts of the two fruit juices were separately treated at 70  for 15 min each so as to inactivate micro-organisms. They were analyzed and blended in different proportions of 70% pawpaw and 30% pineapple, 60% pawpaw and 40% pineapple, 50% pineapple and 50% pawpaw, 40% pawpaw and 60% pineapple. The characterization of the fresh pawpaw and pineapple juice before blending showed that the juices have good quality. The high water content of the product may have affected the viscosity, vitamin C content and total soluble solid of the blended juice to be low. The effects of the process parameters on the quality showed that better quality of the blended juice can be obtained within the optimum temperature range of (50-70 °C) and enzyme concentration range (0.12-0.18 w/v). The ratio of mix 60% pineapple juice: 40% pawpaw juice has better quality. This showed that pawpaw and pineapple juices can blend effectively to produce a quality juice.

Keywords: clarification, pawpaw, pineapple, viscosity, vitamin C

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Authors: Erwan Negre, Ewan J. O'Connor, Juha Toivonen

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The need for CO2 monitoring technologies grows simultaneously with the worldwide concerns regarding environmental challenges. To that purpose, we developed a compact coherent all-fiber ranged-resolved Differential Absorption Lidar (RR-DIAL). It has been designed along a tunable 2x1fiber optic switch set to a frequency of 1 Hz between two Distributed FeedBack (DFB) lasers emitting in the continuous-wave mode at 1571.41 nm (absorption line of CO2) and 1571.25 nm (CO2 absorption-free line), with linewidth and tuning range of respectively 1 MHz and 3 nm over operating wavelength. A three stages amplification through Erbium and Erbium-Ytterbium doped fibers coupled to a Radio Frequency (RF) driven Acousto-Optic Modulator (AOM) generates 100 ns pulses at a repetition rate from 10 to 30 kHz with a peak power up to 2.5 kW and a spatial resolution of 15 m, allowing fast and highly resolved CO2 profiles. The same afocal collection system is used for the output of the laser source and the backscattered light which is then directed to a circulator before being mixed with the local oscillator for heterodyne detection. Packaged in an easily transportable box which also includes a server and a Field Programmable Gate Array (FPGA) card for on-line data processing and storing, our setup allows an effective and quick deployment for versatile in-situ analysis, whether it be vertical atmospheric monitoring, large field mapping or sequestration site continuous oversight. Setup operation and results from initial field measurements will be discussed.

Keywords: CO2 profiles, coherent DIAL, in-situ atmospheric sensing, near infrared fiber source

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Authors: Cheng-Cao Sun, Shu-Jun Li, De-Jia Li

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Through analysis of a published micro-array-based high-throughput assessment, we discovered that miR-1275 was markedly down-regulated in nasopharyngeal carcinoma (NPC) tissues. However, little is known about its effect and mechanism involved in NPC development and progression. In this study, we investigated the role of miR-1275 on the development of NPC. The results indicated that miR-1275 was significantly down-regulated in primary NPC tissues, and very low levels were found in NPC cell lines. Ectopic expression of miR-1275 in NPC cell lines significantly suppressed cell growth as evidenced by cell viability assay and colony formation assay, through inhibition of HOXB5. In addition, miR-1275 suppresses G1/S transition through inhibition of HOXB5. Further, oncogene HOXB5 was revealed to be a putative target of miR-1275, which was inversely correlated with miR-1275 expression in NPC. Collectively, our study demonstrates that as a tumor suppressor, miR-1275 played a pivotal role on NPC through inhibiting cell proliferation, and suppressing G1/S transition by targeting oncogenic HOXB5.

Keywords: microRNA-1275 (miR-1275), HOXB5, nasopharyngeal carcinoma, proliferation

Procedia PDF Downloads 261

Authors: Wei Zha, Jingzeng Zhang, Chen Zhao, Ran Cai, Xueyuan Nie

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Cathodic plasma electrolysis (CPE) is used to create surface textures on cast iron samples for improving the tribological properties. Micro craters with confined size distribution were successfully formed by CPE process. These craters can generate extra hydrodynamic pressure that separates two sliding surfaces, increase the oil film thickness and accelerate the transition from boundary to mixed lubrication. It was found that the optimal crater size was 1.7 μm, at which the maximum lubrication efficiency was achieved. The Taguchi method was used to optimize the process parameters (voltage and roughness) for CPE surface texturing. The orthogonal array and the signal-to-noise ratio were employed to study the effect of each process parameter on the coefficient of friction. The results showed that with higher voltage and lower roughness, the lower friction coefficient can be obtained, and thus the lubrication can be more efficiently used for friction reduction.

Keywords: cathodic plasma electrolysis, friction, lubrication, plasma surface texturing

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Authors: Arnab Majumdar, Sanjoy Sadhukhan

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Although gun barrel steels are an important variety from defense view point, available literatures are very limited. In the present work, an IF grade Ni-Cr-Mo-V high strength low alloy steel is produced in Electric Earth Furnace-ESR Route. Ingot was hot forged to desired dimension with a reduction ratio of 70-75% followed by homogenization, hardening and tempering treatment. Sample chemistry, NMIR, macro and micro structural analyses were done. Mechanical properties which include tensile, impact, and fracture toughness were studied. Ultrasonic testing was done to identify internal flaws. The existing high strength low alloy Ni-Cr-Mo-V steel shows improved properties in modified processing route and heat treatment schedule in comparison to properties noted earlier for manufacturing of gun barrels. The improvement in properties seems to withstand higher explosive loads with the same amount of steel in gun barrel application.

Keywords: gun barrel steels, IF grade, chemistry, physical properties, thermal and mechanical processing, mechanical properties, ultrasonic testing

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Authors: Burmansyah Muhammad, Supriyoto Supriyoto

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Crop yield, quality and food safety are three important components that all estate and food crops must put into consideration to lifting the economic value. These measurements should be evaluated because marketplace demand is simultaneously changing and farmers must adapt quickly to remain competitive. The increase in economic value could be done by producing high quality product that aligns with harvest collector preferences. The purpose of this study is to examine the causal effects of value added farming in agriculture economic aspects towards crop yield, quality and food security. This research is using descriptive survey research by employing data from small-scale cocoa farmers listed to off-taker company, located on Sulawesi area of Indonesia. The questionnaire was obtained from 650 cocoa farmers, selected randomly. Major findings of the study indicate that 78% of respondents agree that agriculture inputs have positive effect on crop yield, quality and food safety. The study recommended that cocoa stakeholders should ensure access to agriculture inputs in first priority and then followed by ensuring access to cocoa supply chain trader and micro-financing. Value Added Farming refers to lifting the economic value of a commodity through particular intervention. Regarding access to agriculture inputs, one of significant intervention is fertilization and plant nutrition management, both organic and inorganic fertilizer. Small-scale cocoa farmers can get access to fertilizer intervention through establishment of demo farm. Ordinary demo farm needs large area, selective requirements, lots of field resources and centralization impact. On the contrary, satellite demo farm is developing to wide-spread the impact of agriculture economic aspects and also the involvement in number of farmers. In Sulawesi Project, we develop leveling strata of small-scale demo farm with group of farmers and local cooperative. With this methodology, all of listed small-scale farmers can get access to agriculture input, micro-financing and how to deliver quality output. PT Pupuk Kaltim is member firm of holding company PT Pupuk Indonesia, private company belongs to the government of Indonesia. The company listed as Indonesia's largest producer of urea fertilizers, besides ammonia, Compound Fertilizer (NPK) and biological fertilizers. To achieve strategic objectives, the company has distinguished award such as SNI Platinum, SGS Award IFA Protect and Sustain Stewardship and Gold Rank of Environment Friendly Company. This achievement has become the strategic foundation for our company to energize value added farming in sustaining food security program. Moreover, to ensure cocoa sustainability farming the company has developed partnership with international companies and Non-Government Organization (NGO).

Keywords: fertilizer and plant nutrition management, good agriculture practices, agriculture economic aspects, value-added farming

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Authors: Anaam H. Al-ShaikhAli, Mansour A. Al-Herz

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The research leverages the proven HS-FCC technology to directly crack crude oils into petrochemical building blocks. Crude oils were subjected to an optimized hydro-processing process where metal contaminants and sulfur were reduced to an acceptable level for feeding the crudes into the HS-FCC technology. The hydro-processing is achieved through a fixed-bed reactor which is composed of 3 layers of catalysts. The crude oil is passed through a dementalization catalyst followed by a desulfurization catalyst and finally a de-aromatization catalyst. The hydroprocessing was conducted at an optimized liquid hourly space velocity (LHSV), temperature, and pressure for an optimal reduction of metals and sulfur from the crudes. The hydro-processed crudes were then fed into a micro activity testing (MAT) unit to simulate the HS-FCC technology. The catalytic cracking of crude oils was conducted over tailored catalyst formulations under an optimized catalyst/oil ratio and cracking temperature for optimal production of total light olefins.

Keywords: petrochemical, catalytic cracking, catalyst synthesis, HS-FCC technology

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Authors: P. M. Keshtiban, M. Zdshakoyan, G. Faragi

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Different severe plastic deformation (SPD) methods are the most successful ways to build nano-structural materials from coarse grain samples without changing the cross-sectional area. One of the most widely used methods in the SPD process is equal channel angler pressing (ECAP). In this paper, ECAP process on Al1050 sheets was evaluated at room temperature by both experiments and finite element method. Since, one of the main objectives of SPD processes is to achieve high equivalent plastic strain (PEEQ) in one cycle, the values of PEEQ obtained by finite element simulation. Also, force-displacement curve achieved by FEM. To study the changes of mechanical properties, micro-hardness tests were conducted on samples and improvement in the mechanical properties were investigated. Results show that there is the good proportion between FEM, theory and experimental results.

Keywords: AL1050, experiments, finite element method, severe plastic deformation

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Authors: Sanaa Ragaee, Paragyani Bora, Wee Teng Tan, Xin Hu

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Goji berry (Lycium barbarum) is a member of the family Solanaceae which is grown widely in China, Tibet, and other parts of Asia. Its fruits are 1–2 cm-long, bright orange-red ellipsoid berries and it has a long tradition as a food and medicinal plant. Goji berries are believed to boost immune system properties. The berries are considered an excellent source of macronutrients, micronutrients, vitamins, minerals and several bioactive components. Studies have shown effects of goji fruit on aging, neuroprotection, general well-being, fatigue/endurance, metabolism/energy expenditure, glucose control in diabetics and glaucoma, antioxidant properties, immunomodulation and anti-tumor activity. Goji berries are being used to prepare Goji beverage, and the remaining solid material is considered as by-product. The by-product is currently unused and disposed as waste despite its potential as a value-added food ingredient. Therefore, this study is intended to evaluate nutritional properties of Goji by-product and its potential applications in the baking industry. The Goji by-product was freeze dried and ground to pass through 1 mm screen prior to evaluation and food use. The Goji by-product was found to be a rich source of fiber (54%) and free phenolic components (1,307 µg/g), protein (13.6%), ash (3.3%) and fat (10%). Incorporation of the Goji by-product in muffins and cookies at various levels (10-40%) significantly improved the nutritional quality of the baked products. The baked products were generally accepted and highly rated by panelists at 20% replacement level. The results indicate the potential of Goji by-product as a value-added ingredient in particular as a source of dietary fiber and protein.

Keywords: Goji, by-product, phenolics, fibers, baked products

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Authors: Till Fehlauer, Blanche Collin, Bernard Angeletti, Andrea Somogyi, Claire Lallemand, Perrine Chaurand, Cédric Dentant, Clement Levard, Jerome Rose

Abstract:

Over the last decades, yttrium (Y) has gained importance in high-tech applications. It is an essential part of alloys and compounds used for lasers, displays, or cell phones, for example. Due to its chemical similarities with the lanthanides, Y is often considered a rare earth element (REE). Despite their increased usage, the environmental behavior of REEs remains poorly understood. Especially regarding their interactions with plants, many uncertainties exist. On the one hand, Y is known to have a negative effect on root development and germination, but on the other hand, it appears to promote plant growth at low concentrations. In order to understand these phenomena, a precise knowledge is necessary about how Y is absorbed by the plant and how it is handled once inside the organism. Contradictory studies exist, stating that due to a similar ionic radius, Y and the other REEs might be absorbed through Ca²⁺-channels, while others suspect that Y has a shared pathway with Al³⁺. In this study, laser ablation coupled ICP-MS, and synchrotron-based micro-X-ray fluorescence (µXRF, beamline Nanoscopium, SOLEIL, France) have been used in order to localize Y within the plant tissue and identify associated elements. The plant used in this study is Saxifraga paniculata, a rugged alpine plant that has shown an affinity for Y in previous studies (in prep.). Furthermore, Saxifraga paniculata performs guttation, which means that it possesses phloem sap secreting openings on the leaf surface that serve to regulate root pressure. These so-called hydathodes could provide special insights in elemental transport in plants. The plants have been grown on Y doped soil (500mg/kg DW) for four months. The results showed that Y was mainly concentrated in the roots of Saxifraga paniculata (260 ± 85mg/kg), and only a small amount was translocated to the leaves (10 ± 7.8mg/kg). µXRF analysis indicated that within the root transects, the majority of Y remained in the epidermis and hardly penetrated the stele. Laser ablation coupled ICP-MS confirmed this finding and showed a positive correlation in the roots between Y, Fe, Al, and to a lesser extent Ca. In the stem transect, Y was mainly detected in a hotspot of approximately 40µm in diameter situated in the endodermis area. Within the stem and especially in the hotspot, Y was highly colocalized with Al and Fe. Similar-sized Y hotspots have been detected in/on the leaves. All of them were strongly colocalized with Al and Fe, except for those situated within the hydathodes, which showed no colocalization with any of the measured elements. Accordingly, a relation between Y and Ca during root uptake remains possible, whereas a correlation to Fe and Al appears to be dominant in the aerial parts, suggesting common storage compartments, the formation of complexes, or a shared pathway during translocation.

Keywords: laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), Phytoaccumulation, Rare earth elements, Saxifraga paniculata, Synchrotron-based micro-X-ray fluorescence, Yttrium

Procedia PDF Downloads 145

Authors: Dibyendu Adak, Saroj Mandal

Abstract:

The fly ash based geopolymer concrete generally requires heat activation after casting, which has been considered as an important limitation for its practical application. Such limitation can be overcome by a modification in the process at the time of mixing of ingredients (fly and activator fluid) for geopolymer concrete so that curing can be made at ambient temperature. This process modified geopolymer concrete shows an appreciable improvement in structural performance compared to conventional heat cured geopolymer concrete and control cement concrete. The improved durability performance based on water absorption, sulphate test, and RCPT is also noted. The microstructural properties analyzed through Field Emission Scanning Electron Microscope (FESEM) with Energy Dispersive X-ray Spectroscopy (EDS) and X-ray Diffraction (XRD) techniques show the better interaction of fly ash and activator solution at early ages for the process modified geopolymer concrete. This accelerates the transformation of the amorphous phase of fly ash to the crystalline phase.

Keywords: fly ash, geopolymer concrete, process modification, structural properties, durability, micro-structures

Procedia PDF Downloads 157

Authors: Tae-min Byun, Chang-soo Chon, Dong-hyun Seo, Han-sung Kim, Bum-mo Ahn, Hui-suk Yun, Cheolwoong Ko

Abstract:

In this study, a 3-point bending computational analysis of normal and osteoporosis mouse models was performed based on the Micro-CT image information of the femurs. The finite element analysis (FEA) found 1.68 N (normal group) and 1.39 N (osteoporosis group) in the average maximum force, and 4.32 N/mm (normal group) and 3.56 N/mm (osteoporosis group) in the average stiffness. In the comparison of the 3-point bending test results, the maximum force and the stiffness were different about 9.4 times in the normal group and about 11.2 times in the osteoporosis group. The difference between the analysis and the test was greatly significant and this result demonstrated improvement points of the material properties applied to the computational analysis of this study. For the next study, the material properties of the mouse femur will be supplemented through additional computational analysis and test.

Keywords: 3-point bending test, mouse, osteoporosis, FEA

Procedia PDF Downloads 344

Authors: K. D. Mandal, Anil Kumar Mourya, Ankur Khare

Abstract:

Ceramics of 0.6 CaCu3TiO12 – 0.2 Bi2/3Cu3TiO12 – 0.2 Y2/3Cu3TiO12 (i.e. 0.6CCTO-0.2BCTO-0.2 YCTO) were prepared via semi - wet route. The phase structure of the sample was identified by X-Ray diffraction. The micro structure of the sample was observed by SEM, which displays grains of different shapes having diameter in range of 2 µm–4 µm. We have studied the frequency and temperature dependence of permittivity and impedance of the compound with LCR Meter in the range of 100 Hz–1 MHz and 300–500 K. The material shows its highest dielectric constant (428000) at 100 Hz and 368 K. The material shows Debye–like relaxation and their dielectric constant are independent of frequency and temperature over a wide range. The sample shows two electrical responses in impedance formalism, indicating that there are two distinct contributions. We attribute them to grain and grain boundaries in the ceramic sample and explain the dielectric behaviors by Maxwell–Wagner relaxation arising at the interfaces between grain and their boundaries.

Keywords: complex perovskite, ceramics composite, impedance study, SEM

Procedia PDF Downloads 437