A special magnetic coupler structure for three-coil wireless power transfer : analysis, design, and experimental verification
- Authors: Wang, Heshou , Cheng, Ka , Li, Xiaofei , Hu, Jiefeng
- Date: 2021
- Type: Text , Journal article
- Relation: IEEE Transactions on Magnetics Vol. 57, no. 11 (2021), p.
- Full Text: false
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- Description: In this article, a special magnetic coupler for three-coil wireless power transfer (WPT) is proposed to eliminate the mutual inductance between the source coil and the receiver coil, which can significantly improve the design freedom. Specifically, unipolar Q coil, mixed QDD coil, and bipolar DD coil are designed for the source coil, the transmitter coil ( $\text{T}_{\mathrm {X}}$ ), and the receiver coil ( $\text{R}_{\mathrm {X}}$ ), respectively. By making use of unipolar coils and bipolar coils, this structure magnetically decouples the receiver coil from the source coil. Meanwhile, under different lateral misalignment conditions, this new coupler facilitates maintaining high efficiency. A laboratory prototype has been constructed to validate the proposed structure, demonstrating that the proposed structure can realize inherent characteristics, enhance misalignment tolerance, and energy transfer. The potential applications are EV systems, but this design can be generalizable to other three-coil systems. © 1965-2012 IEEE.
A study on the corrosion characteristics of internal combustion engine materials in second-generation jatropha curcas biodiesel
- Authors: Shahabuddin, M. , Mofijur, M. , Shuvho, Md Bengir , Chowdhury, M. , Kalam, Md Abul , Masjuki, Haji , Chowdhury, Mohammad
- Date: 2021
- Type: Text , Journal article
- Relation: Energies Vol. 14, no. 14 (2021), p.
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- Description: The corrosiveness of biodiesel affects the fuel processing infrastructure and different parts of an internal combustion (IC) engine. The present study investigates the corrosion behaviour of automotive materials such as stainless steel, aluminium, cast iron, and copper in 20% (B20) and 30% (B30) by volume second-generation Jatropha biodiesel using an immersion test. The results were compared with petro-diesel (B0). Various fuel properties such as the viscosity, density, water con-tent, total acid number (TAN), and oxidation stability were investigated after the immersion test using ASTM D341, ASTM D975, ASTM D445, and ASTM D6751 standards. The morphology of the corroded materials was investigated using optical microscopy and scanning electron microscopy SEM), whereas the elemental analysis was carried out using energy-dispersive X-ray spectroscopy (EDS). The highest corrosion using biodiesel was detected in copper, while the lowest was detected in stainless steel. Using B20, the rate of corrosion in copper and stainless steel was 17% and 14% higher than when using diesel, which further increased to 206% and 86% using B30. After the immersion test, the viscosity, water content, and TAN of biodiesel were increased markedly compared to petro-diesel. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Influence of silica nano-additives on performance and emission characteristics of soybean biodiesel fuelled diesel engine
- Authors: Gavhane, R. , Kate, A. , Soudagar, Manzoore , Wakchaure, V. , Shahabuddin, M.
- Date: 2021
- Type: Text , Journal article
- Relation: Energies Vol. 14, no. 5 (Mar 2021), p. 16
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- Description: The present study examines the effect of silicon dioxide (SiO2) nano-additives on the performance and emission characteristics of a diesel engine fuelled with soybean biodiesel. Soybean biofuel was prepared using the transesterification process. The morphology of nano-additives was studied using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS). The Ultrasonication process was used for the homogeneous blending of nano-additives with biodiesel, while surfactant was used for the stabilisation of nano-additives. The physicochemical properties of pure and blended fuel samples were measured as per ASTM standards. The performance and emissions characteristics of different fuel samples were measured at different loading conditions. It was found that the brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) increased by 3.48-6.39% and 5.81-9.88%, respectively, with the addition of SiO2 nano-additives. The carbon monoxide (CO), hydrocarbon (HC) and smoke emissions for nano-additive added blends were decreased by 1.9-17.5%, 20.56-27.5% and 10.16-23.54% compared to SBME25 fuel blends. *Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “M. Shahabuddin” is provided in this record**
Optical characterisation of alumina–mullite materials for solar particle receiver applications
- Authors: Chen, Jiangjing , Wheeler, Vincent , Liu, Boqing , Kumar, Apurv , Coventry, Joe , Lipiński, Wojciech
- Date: 2021
- Type: Text , Journal article
- Relation: Solar Energy Materials and Solar Cells Vol. 230, no. (2021), p.
- Full Text: false
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- Description: Alumina–mullite particles are used in high-temperature solar thermal applications such as solar particle receivers. In this study, optical properties of alumina–mullite materials with variable content of alumina and mullite are determined in the spectral range of 0.193–1.69 μm. Variable angle spectroscopic ellipsometry is performed for alumina–mullite thin films, which are fabricated by magnetron sputtering. The thin films are characterised by scanning electron microscopy, atomic force microscopy, and energy dispersive spectroscopy methods. The B-spline model is employed to generate ellipsometric parameters to fit the measured data and to obtain the optical properties. The investigated materials of variable content of alumina and mullite have a similar refractive index in the considered spectral range. The absorptive index of the alumina–mullite materials in the spectral range of 0.193–0.4 μm is higher than in the range 0.4–1.69 μm. The absorptive index decreases with increasing content of alumina in the spectral range of 0.193–0.4 μm. The material composed of similar proportions of alumina and mullite yields the highest absorptive index in the spectral range of 0.4–1.1 μm. The optical properties determined for the alumina–mullite materials are applied to obtain the radiative properties of spherical homogeneous particles. Mie theory is used to calculate absorption and scattering efficiency factors, as well as the scattering phase function. In addition, the scattering phase functions are obtained using the Henyey–Greenstein approximation and the transport approximation. The Monte Carlo ray-tracing method is employed to study the radiative transfer in a model one-dimensional particle curtain containing polydisperse particles exposed to high-flux solar irradiation. It is found that the overall reflectance, absorptance and transmittance of the particles only weakly depend on the optical properties of the materials investigated. © 2021 Elsevier B.V. Corrigendum to “Optical characterisation of alumina–mullite materials for solar particle receiver applications” [Solar Energy Mater. Solar Cell. 230 (2021) 111170] (Solar Energy Materials and Solar Cells (2021) 230, (S0927024821002130), (10.1016/j.solmat.2021.111170)) Solar Energy Materials and Solar Cells, Volume 231, October 2021, Article number 111225. https://doi.org/10.1016/j.solmat.2021.111225
- Description: Alumina–mullite particles are used in high-temperature solar thermal applications such as solar particle receivers. In this study, optical properties of alumina–mullite materials with variable content of alumina and mullite are determined in the spectral range of 0.193–1.69 μm. Variable angle spectroscopic ellipsometry is performed for alumina–mullite thin films, which are fabricated by magnetron sputtering. The thin films are characterised by scanning electron microscopy, atomic force microscopy, and energy dispersive spectroscopy methods. The B-spline model is employed to generate ellipsometric parameters to fit the measured data and to obtain the optical properties. The investigated materials of variable content of alumina and mullite have a similar refractive index in the considered spectral range. The absorptive index of the alumina–mullite materials in the spectral range of 0.193–0.4 μm is higher than in the range 0.4–1.69 μm. The absorptive index decreases with increasing content of alumina in the spectral range of 0.193–0.4 μm. The material composed of similar proportions of alumina and mullite yields the highest absorptive index in the spectral range of 0.4–1.1 μm. The optical properties determined for the alumina–mullite materials are applied to obtain the radiative properties of spherical homogeneous particles. Mie theory is used to calculate absorption and scattering efficiency factors, as well as the scattering phase function. In addition, the scattering phase functions are obtained using the Henyey–Greenstein approximation and the transport approximation. The Monte Carlo ray-tracing method is employed to study the radiative transfer in a model one-dimensional particle curtain containing polydisperse particles exposed to high-flux solar irradiation. It is found that the overall reflectance, absorptance and transmittance of the particles only weakly depend on the optical properties of the materials investigated. © 2021 Elsevier B.V. Corrigendum to “Optical characterisation of alumina–mullite materials for solar particle receiver applications” [Solar Energy Mater. Solar Cell. 230 (2021) 111170] (Solar Energy Materials and Solar Cells (2021) 230, (S0927024821002130), (10.1016/j.solmat.2021.111170)) Solar Energy Materials and Solar Cells, Volume 231, October 2021, Article number 111225
Tissue programmed hydrogels functionalized with GDNF improve human neural grafts in Parkinson's disease
- Authors: Hunt, Cameron , Penna, Vanessa , Gantner, Carlos , Moriarty, Niamh , Long, Benjamin
- Date: 2021
- Type: Text , Journal article
- Relation: Advanced Functional Materials Vol. 31, no. 47 (2021), p.
- Full Text: false
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- Description: The survival and synaptic integration of transplanted dopaminergic (DA) progenitors are essential for ameliorating motor symptoms in Parkinson's disease (PD). Human pluripotent stem cell (hPSC)-derived DA progenitors are, however, exposed to numerous stressors prior to, and during, implantation that result in poor survival. Additionally, hPSC-derived grafts show inferior plasticity compared to fetal tissue grafts. These observations suggest that a more conducive host environment may improve graft outcomes. Here, tissue-specific support to DA progenitor grafts is provided with a fully characterized self-assembling peptide hydrogel. This biomimetic hydrogel matrix is programmed to support DA progenitors by i) including a laminin epitope within the matrix; and ii) shear encapsulating glial cell line-derived neurotrophic factor (GDNF) to ensure its sustained delivery. The biocompatible hydrogel biased a 51% increase in A9 neuron specification—a subpopulation of DA neurons critical for motor function. The sustained delivery of GDNF induced a 2.7-fold increase in DA neurons and enhanced graft plasticity, resulting in significant improvements in motor deficits at 6 months. These findings highlight the therapeutic benefit of stepwise customization of tissue-specific hydrogels to improve the physical and trophic support of human PSC-derived neural transplants, resulting in improved standardization, predictability and functional efficacy of grafts for PD. © 2021 Wiley-VCH GmbH. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Benjamin Long” is provided in this record**
Micro-scale heat transfer modelling of the contact line region of a boiling-sodium bubble
- Authors: Iyer, Siddharth , Kumar, Apurv , Coventry, Joe , Pye, John , Lipiński, Wojciech
- Date: 2020
- Type: Text , Journal article
- Relation: International Journal of Heat and Mass Transfer Vol. 160, no. (2020), p.
- Full Text: false
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- Description: The use of boiling liquid metals such as sodium is attractive for providing a near-isothermal heat source for engineering applications. However, previous use of boiling sodium as a coolant in nuclear reactors and as a heat transfer fluid in solar thermal applications has shown that the boiling process is unstable. To stabilise the flow, it is imperative to gain a better understanding of the boiling phenomena. An integral part of the boiling process is the evaporation of the region where the liquid-vapour interface meets the heater wall, referred to as the contact line region. The heat transfer modelling of this region formed below a single bubble in nucleate pool boiling of sodium is considered in this study. A contact line model previously developed for high Prandtl number flows is extended by including the effect of an electron pressure component which is unique to liquid metals. The assumptions made in the model are critically assessed to determine their validity for modelling micro-scale evaporation in sodium. The model was used to show that the evaporative heat flux from the contact line region in sodium can be up to six times larger compared to a high Prandtl number fluid FC-72 for a superheat of 15 K, owing to the high thermal conductivity of sodium. Furthermore, a study on the influence of specific characteristics of sodium — high boiling superheat and presence of an electron pressure — showed that the evaporative heat flux increases with increasing superheat and decreases with increasing electron pressure. © 2020 Elsevier Ltd
- Description: We gratefully acknowledge the financial support from the Australian Research Council (grant no. LP150101189 ). We thank our project partner Vast Solar Pty Ltd for their support and contributions.
Numerical modelling of radiation absorption in a novel multi-stage free-falling particle receiver
- Authors: Kumar, Apurv , Lipinski, Wojciech , Kim, Jin-Soo
- Date: 2020
- Type: Text , Journal article
- Relation: International Journal of Heat and Mass Transfer Vol. 146, no. (Jan 2020), p. 11
- Full Text: false
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- Description: A novel multi-stage free-falling particle receiver design is proposed to improve the simple free-falling concept by enhancing the hydrodynamic stability and improving the radiation absorption of the particle curtain. The multi-stage design arising from repeated re-initialisation of the particle curtain by using intermediate troughs in the receiver results in an increased average volume fraction and residence time of the particles. The present work numerically solves the mass, momentum and radiative transfer equation for an isothermal two dimensional Eulerian-Eulerian particle-gas multiphase flow equations to estimate the absorption characteristics of the particle curtain. The multi-stage receiver concept significantly improves the absorptance of the curtain and reduces the reflection losses by over 50%. The reflection losses are seen to be insensitive to increase in size of the receiver making the multi-stage concept highly scalable. (C) 2019 Elsevier Ltd. All rights reserved.
Optimization of an ultrasonic-assisted biodiesel production process from one genotype of rapeseed (TERI (OE) R-983) as a novel feedstock using response surface methodology
- Authors: Almasi, Sara , Ghobadian, Barat , Najafi, Gholam , Yusaf, Talal , Soufi, Masoud , Hoseini, Seyed
- Date: 2019
- Type: Text , Journal article
- Relation: Energies Vol. 12, no. 14 (2019), p. 1-14
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- Description: In recent years, due to the favorable climate conditions of Iran, the cultivation of rapeseed has increased significantly. The aim of this study was to investigate the possibility of biodiesel production from one genotype of rapeseed (TERI (OE) R-983). An ultrasonic approach was used in order to intensify the reaction. Response surface methodology (RSM) was applied to identify the optimum conditions of the process. The results of this research showed that the conversion of biodiesel was found to be 87.175% under the optimized conditions of a 4.63:1 molar ratio (methanol to oil), 56.50% amplitude, and 0.4 s pulses for a reaction time of 5.22 min. Increasing the operating conditions, such as the molar ratio from 4:1 to 5.5:1, amplitude from 50% to 72.5%, reaction time from 3 min to 7 min, and pulse from 0.4 s to 1 s, increased the FAME (fatty acid methyl esters) yield by approximately 4.5%, 2.3%, 1.2%, and 0.5%, respectively. The properties of the TERI (OE) R-983 methyl ester met the requirements of the biodiesel standard (ASTM D6751), indicating the potential of the produced biodiesel as an alternative fuel.
Performance assessment of a solar dryer system using small parabolic dish and alumina/oil nanofluid : simulation and experimental study
- Authors: Arkian, Amir , Najafi, Gholamhassan , Gorjian, Shiva , Loni, Reyhaneh , Bellos, Evangelos , Yusaf, Talal
- Date: 2019
- Type: Text , Journal article
- Relation: Energies Vol. 12, no. 24 (Dec 2019), p. 22
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- Description: In this study, a small dish concentrator with a cylindrical cavity receiver was experimentally investigated as the heat source of a dryer. The system was examined for operation with pure thermal oil and Al2O3/oil nanofluid as the working fluids in the solar system. Moreover, the design, the development, and the evaluation of the dried mint plant are presented in this work. Also, the solar dryer system was simulated by the SolidWorks and ANSYS CFX software. On the other side, the color histogram of the wet and dried mint samples based on the RGB method was considered. The results revealed that the different temperatures of the solar working fluids at the inlet and outlet of the cavity receiver showed similar trend data compared to the variation of the solar radiation during the experimental test. Moreover, it is found that the cavity heat gain and thermal efficiency of the solar system was improved by using the nanofluid as the solar working fluid. Furthermore, the required time for mint drying had decreased by increasing the drying temperature and increasing air speed. The highest drying time was measured equal to 320 min for the condition of the air speed equal to 0.5 m/s and the drying temperature of 30 degrees C. A good agreement was observed between the calculated numerical results and measured experimental data. Finally, based on the color histogram of the wet and dried mint samples, it was concluded that intensity amount of the red color of the mint increased with the drying process compared to intensity amount of the red color of the wet mint sample.
The impacts of water pricing and non-pricing policies on sustainable water resources management : A case of Ghorveh Plain at Kurdistan province, Iran
- Authors: Asaadi, Mohammad , Mortazavi, Seyed , Zamani, Omid , Najafi, Gholam , Yusaf, Talal , Hoseini, Seyed
- Date: 2019
- Type: Text , Journal article
- Relation: Energies Vol. 12, no. 14 (2019), p. 1-16
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- Description: As with other regions of Iran, due to excessive extraction of groundwater for intense agricultural activity, Ghorveh plain, a water-scarce irrigation district in the west of Iran, has faced a serious water crisis during the last decade. The present study investigates the impacts of two scenario policies, namely, non-price policy (as a supply-oriented policy) and water pricing policies (as a demand-oriented policy) on agricultural sector of Ghorveh Plain, using positive mathematical programming (PMP). The model was calibrated by using farm-level data for the crop years in 2016-2017. Our findings indicate that applying water supply constraint policy will change the land use and cropping pattern to the crops with higher water productivity. The increase of water resource constraints can lead to the increase of water economic return which indicates a rising value of water resources shortage, warning the producers of the agriculture sector to allocate water to the crops with higher economic value under the water resources shortage conditions. In addition, the findings underline that in a situation where the price of irrigation water is low due to the low elasticity of water demand in the agriculture sector, formulating the economic instruments such as rising water prices does not solely suffice to achieve sustainable water resource management. However, mixed scenarios emphasized that the water distribution policies should be aligned with the increases in water cost.
The influence of emulsified water fuel containing fresh water microalgae on diesel engine performance, combustion, vibration and emission
- Authors: Al-Lwayzy, Saddam , Yusaf, Talal , Saleh, Khalid , Yousif, Belal
- Date: 2019
- Type: Text , Journal article
- Relation: Energies Vol. 12, no. 13 (2019), p. 1-17
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- Description: Microalgae is considered as an excellent potential renewable source of fuel in many forms including powder or slurry. A high percentage of emulsified water in the fuel is reported to reduce diesel engines’ emissions such as NOx, but that will compromise the engine output power. Using microalgae powder as an additive to enhance the emulsified water fuel heating value is the main objective of this work. Diesel engine combustion, vibration, performance and emissions were evaluated for pure cottonseed biodiesel (CS-B100), emulsified water 20% (vol.) in cottonseed biodiesel (CSB-E20) and emulsified water 20% (vol.) containing Fresh Water Microalgae Chlorella Vulgaris (FWM-CV) in cottonseed biodiesel (CSB-ME20). The emulsified water fuels showed a reduction in in-cylinder pressure, vibration, brake power, torque, exhaust gas temperature, CO2 and NOx, while BSFC and O2 were higher than the pure biodiesel (CS-B100). CSB-ME20 produced higher power and torque than CSB-E20 due to the presence of microalgae in the fuel that increased the energy content of the fuel.
A novel concept for three-phase cascaded multilevel inverter topologies
- Authors: Hasan, Mubashwar , Abu-Siada, Ahmed , Islam, Syed , Muyeen, S.
- Date: 2018
- Type: Text , Journal article
- Relation: Energies Vol. 11, no. 2 (2018), p. 1-16
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- Description: One of the key challenges in multilevel inverters (MLIs) design is to reduce the number of components used in the implementation while maximising the number of output voltage levels. This paper proposes a new concept that facilitates a device count reduction technique of existing cascaded MLIs. Moreover, the proposed concept can be utilised to extend existing single phase cascaded MLI topologies to three-phase structure without tripling the number of semiconductor components and input dc-supplies as per the current practice. The new generalized concept involves two stages; namely, cascaded stage and phase generator stage. The phase generator stage is a combination of a conventional three-phase two level inverter and three bi-directional switches while the cascaded stage can employ any existing cascaded topology. A laboratory prototype model is built and extensive experimental analyses are conducted to validate the feasibility of the proposed cascaded MLI concept.
Artificial neural network modeling and sensitivity analysis of performance and emissions in a compression ignition engine using biodiesel fuel
- Authors: Jaliliantabar, Farzad , Ghobadian, Barat , Najafi, Gholamhassan , Yusaf, Talal
- Date: 2018
- Type: Text , Journal article
- Relation: Energies Vol. 11, no. 9 (2018), p. 1-24
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- Description: In the present research work, a neural network model has been developed to predict the exhaust emissions and performance of a compression ignition engine. The significance and novelty of the work, with respect to existing literature, is the application of sensitivity analysis and an artificial neural network (ANN) simultaneously in order to predict the engine parameters. The inputs of the model were engine load (0, 25, 50, 75 and 100%), engine speed (1700, 2100, 2500 and 2900 rpm) and the percent of biodiesel fuel derived from waste cooking oil in diesel fuel (B0, B5, B10, B15 and B20). The relationship between the input parameters and engine cylinder performance and emissions can be determined by the network. The global sensitivity analysis results show that all the investigated factors are effective on the created model and cannot be ignored. In addition, it is found that the most emissions decreased while using biodiesel fuel in the compression ignition engine.
Design and analysis of nano-structured gratings for conversion efficiency improvement in GaAs solar cells
- Authors: Das, Narottam , Islam, Syed
- Date: 2016
- Type: Text , Journal article
- Relation: Energies Vol. 9, no. 9 (2016), p. 1-13
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- Description: This paper presents the design and analysis of nano-structured gratings to improve the conversion efficiency in GaAs solar cells by reducing the light reflection losses. A finite-difference time domain (FDTD) simulation tool is used to design and simulate the light reflection losses of the subwavelength grating (SWG) structure in GaAs solar cells. The SWG structures perform as an excellent alternative antireflective (AR) coating due to their capacity to reduce the reflection losses in GaAs solar cells. It allows the gradual change in the refractive index that confirms an excellent AR and the light trapping properties, when compared with the planar thin film structures. The nano-rod structure performs as a single layer AR coating, whereas the triangular (i.e., conical or perfect cone) and parabolic (i.e., trapezoidal/truncated cone) shaped nano-grating structures perform as a multilayer AR coating. The simulation results confirm that the reflection loss of triangular-shaped nano-grating structures having a 300-nm grating height and a 830-nm period is about 2%, which is about 28% less than the flat type substrates. It also found that the intermediate (i.e., trapezoidal and parabolic)-shaped structures, the light reflection loss is lower than the rectangular shaped nano-grating structure, but higher than the triangular shaped nano-grating structure. This analysis confirmed that the triangular shaped nano-gratings are an excellent alternative AR coating for conversion efficiency improvement in GaAs solar cells.
Electrokinetics to modify strength characteristics of soft clayey soils : A laboratory based investigation
- Authors: Jayasekera, Samudra
- Date: 2015
- Type: Text , Journal article
- Relation: Electrochimica Acta Vol. 181, no. (2015), p. 39-47
- Full Text: false
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- Description: The effects of Electrokinetic (EK) processing on compressive strength characteristics of two types of soils were investigated using laboratory experimental models. Soils were collected from soft alluvial soil deposit (Soil S1) and basaltic soil deposit (Soil S2) in central Victoria, Australia. A layer of soil was placed in glass tanks (90 cm × 18 cm plan area) and compacted to a known density and water content typical of field conditions. Using electrodes inserted into the soil, a direct current was passed across the soil under various voltage gradients (0.5, 1.0, 2.0 V/cm) for periods of 7, 14, 30 and 60 days. Throughout the experimental duration, test samples were supplied with a continuous flow of water via the hollow core anode from external reservoirs. Unconfined compression (UC) tests were conducted on original (untreated) soils and EK processed soils. From the test results it is noted that, soil compressive strength increases with the increasing processing time and increasing voltage gradients, at various rates. Under certain voltage gradients and processing times, around 175% and 200% strength increases are observed. In general, stress increases of at least 30% or more are reported for both soils under all test conditions. It is apparent that the variation in strength can be attributed to several complex and interrelated processes that become active under EK processing. These may include, (i) Electroosmotic advection - When a soil is subjected to EK processing with an open electrode configuration, the water content of the soil varies predominantly due to the electroosmotic advection while natural drying and evaporation could also add to the decrease in water content to some extent, depending on the time and environmental conditions such as temperature and humidity. The test results show that with the decrease in water content, there is a corresponding increase in the strength. (ii) Electromigration - The electromigration of charged ions and their interaction with clay minerals can also affect the soil strength due to the variations in the DDL (Diffused Double Layer) ionic concentration and subsequent modifications in the soil structure. (iii) Ionic Diffusion and Aging - After the complete termination of EK processes, the ionic concentrations still continued to modify at a slower rate. This is considered to be due to the ionic diffusion. In this phase too, cementation bonds may continue to develop that could contribute to the increase in soil strength. During this period, two other processes, i.e. natural drying of soil and aging may continue that can also affect the variation of soil strength. © 2015 Elsevier Ltd. All rights reserved.
Yield and characteristics of pyrolysis products obtained from Schizochytrium limacinum under different temperature regimes
- Authors: Li, Gang , Zhou, Yuguang , Ji, Fang , Liu, Ying , Adhikari, Benu , Tian, Li , Ma, Zonghu , Dong, Renjie
- Date: 2013
- Type: Text , Journal article
- Relation: Energies Vol. 6, no. 7 (2013), p. 3339-3352
- Full Text: false
- Reviewed:
- Description: Pyrolysis-gas chromatographic mass spectrometry (Py-GC/MS) was used to determine the yield and chemical composition of the pyrolysis products of Schizochytrium limacinum. The pyrolysis was carried out by varying the temperature from 300 °C to 800 °C. It was found that the main decomposition temperature of Schizochytrium limacinum was 428.16 °C, at which up to 66.5% of the mass was lost. A further 18.7% mass loss then occurred in a relatively slow pace until 760.2 °C due to complete decomposition of the ash content of Schizochytrium limacinum. The pyrolysis of Schizochytrium limacinum at 700 °C produced the maximum yield (67.7%) of pyrolysis products compared to 61.2% at 400 °C. While pollutants released at 700 °C (12.3%) was much higher than that of 400 °C (2.1%). Higher temperature will lead to more pollutant (nitrogen compounds and PAHs) release,which is harmful to the environment. Considering the reasonably high yield and minimum release of pollutants, a lower pyrolysis temperature (400 °C) was found to be optimum for producing biofuel from Schizochytrium limacinum.
- Description: C1
Optimization of a quarter-car suspension model coupled with the driver biomechanical effects
- Authors: Kuznetsov, Alexey , Mammadov, Musa , Sultan, Ibrahim , Hajilarov, Eldar
- Date: 2011
- Type: Text , Journal article
- Relation: Journal of Sound and Vibration Vol. 330, no. 12 (2011), p. 2937-2946
- Full Text: false
- Reviewed:
- Description: In this paper a Human–Vehicle–Road (HVR) model, comprising a quarter-car and a biomechanical representation of the driver, is employed for the analysis. Differential equations are provided to describe the motions of various masses under the influence of a harmonic road excitation. These equations are, subsequently, solved to obtain a closed form mathematical expression for the steady-state vertical acceleration measurable at the vehicle–human interface. The solution makes it possible to find optimal parameters for the vehicle suspension system with respect to a specified ride comfort level. The quantitative definition given in the ISO 2631 standard for the ride comfort level is adopted in this paper for the optimization procedure. Numerical examples, based on actually measured road profiles, are presented to prove the validity of the proposed approach and its suitability for the problem at hand.
Fe and S K-edge XAS determination of iron-sulfur species present in a range of acid sulfate soils : Effects of particle size and concentration on quantitative XANES determinations
- Authors: Morgan, Kate , Burton, Edward , Cook, Perran , Raven, Mark , Fitzpatrick, Rob W. , Bush, Richard , Sullivan, Leigh , Hocking, Rosalie
- Date: 2009
- Type: Text , Conference paper
- Relation: 14th International Conference on X-ray Absorption Fine Structure (XAFS14); Camerino, Italy; 26th-31st July 2009. Vol. 190, p. 1-5
- Full Text: false
- Reviewed:
- Description: Acid sulfate soils (ASS) are soils and soft sediments in which sulfuric acid may be produced from iron sulfides or have been produced leaving iron oxyhydroxysulfates in amounts that have a long lasting effect on soil characteristics. If soil material is exposed to rotting vegetation or other reducing material, the Fe-oxyhydroxysulfates can be bacterially reduced to sulfides including disulfides (pyrite and marcasite), and Monosulfidic Black Ooze (MBO) a poorly characterised material known to be a mixture of iron sulfides (especially mackinawite) and organic matter. The chemistry of these environments is strongly affected by Fe and S cycling processes and herein we have sought to identify key differences in environments that occur as a function of Fe and S concentration. In addition to our chemical results, we have found that the effects of particle size on self absorption in natural sediments play an important role in the spectroscopic identification of the relative proportions of different species present. © 2009 IOP Publishing Ltd.