Search results for: Organic semiconductor
625 Metal-Oxide-Semiconductor-Only Process Corner Monitoring Circuit
Authors: Davit Mirzoyan, Ararat Khachatryan
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A process corner monitoring circuit (PCMC) is presented in this work. The circuit generates a signal, the logical value of which depends on the process corner only. The signal can be used in both digital and analog circuits for testing and compensation of process variations (PV). The presented circuit uses only metal-oxide-semiconductor (MOS) transistors, which allow increasing its detection accuracy, decrease power consumption and area. Due to its simplicity the presented circuit can be easily modified to monitor parametrical variations of only n-type and p-type MOS (NMOS and PMOS, respectively) transistors, resistors, as well as their combinations. Post-layout simulation results prove correct functionality of the proposed circuit, i.e. ability to monitor the process corner (equivalently die-to-die variations) even in the presence of within-die variations.Keywords: Detection, monitoring, process corner, process variation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1325624 A Novel Single-Wavelength All-Optical Flip-Flop Employing Single SOA-MZI
Authors: H. Kaatuzian, M. Sedghi, S. Khatami
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In this paper, by exploiting a single semiconductor optical amplifier-Mach Zehnder Interferometer (SOA-MZI), an integratable all-optical flip-flop (AOFF) is proposed. It is composed of a SOA-MZI with a bidirectional coupler at the output. Output signals of both bar and crossbar of the SOA-MZI is fed back to SOAs located in the arms of the Mach-Zehnder Interferometer (MZI). The injected photon-rates to the SOAs are modulated by feedback signals in order to form optical flip-flop. According to numerical analysis, Gaussian optical pulses with the energy of 15.2 fJ and 20 ps duration with the full width at half-maximum criterion, can switch the states of the SR-AOFF. Also simulation results show that the SR-AOFF has the contrast ratio of 8.5 dB between two states with the transition time of nearly 20 ps.Keywords: All Optical, Flip-Flop, Mach-Zehnder Interferometer (MZI), Semiconductor Optical Amplifier (SOA).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2025623 The Motivating and Demotivating Factors at the Learning of English Center in Thailand
Authors: Bella Llego
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This study aims to investigate the motivating and de-motivating factors that affect the learning ability of students attending the English Learning Center in Thailand. The subjects of this research were 20 students from the Hana Semiconductor Co., Limited. The data were collected by using questionnaire and analyzed using the SPSS program for the percentage, mean and standard deviation. The research results show that the main motivating factor in learning English at Hana Semiconductor Co., Ltd. is that it would help the employees to communicate with foreign customers and managers. Other reasons include the need to read and write e-mails, and reports in English, as well as to increase overall general knowledge. The main de-motivating factor is that there is a lot of vocabulary to remember when learning English. Another de-motivating factor is that when homework is given, the students have no time to complete the tasks required of them at the end of the working day.
Keywords: Motivating, demotivating, English learning center, student communicate.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1221622 Depositional Environment and Source Potential of Devonian Source Rock, Ghadames Basin, Southern Tunisia
Authors: S. Mahmoudi, A. Belhaj Mohamed, M. Saidi, F. Rezgui
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Depositional environment and source potential of the different organic-rich levels of Devonian age (up to 990m thick) from the onshore EC-1 well (Southern Tunisia) were investigated based on the analysis of more than 130 cutting samples by different geochemical techniques (Rock-Eval pyrolysis, GC-MS). The obtained results including Rock Eval Pyrolysis data and biomarker distribution (terpanes, steranes and aromatics) have been used to describe the depositional environment and to assess the thermal maturity of the Devonian organic matter. These results show that the Emsian deposits exhibit poor to fair TOC contents. The associated organic matter is composed of mixed kerogen (type II/III), as indicated by the predominance of C29 steranes over C27 and C28 homologous, that was deposited in a slightly reduced environment favoring organic matter preservation. Thermal maturity assessed from Tmax, TNR and MPI-1 values shows a mature stage of organic matter. The Middle Devonian (Eifelian) shales are rich in type II organic matter that was deposited in an open marine depositional environment. The TOC values are high and vary between 2 and 7% indicating good to excellent source rock. The relatively high HI values (reaching 547 mg HC/g TOC) and the low values of t19/t23 tricyclic terpane ratio (< 0.2) confirm the marine origin of the organic matter (type II). During the Upper Devonian, the organic matter was deposited under variable redox conditions, oxic to suboxic which is clearly indicated by the low C35/C34 hopanes ratio, immature to marginally mature with the vitrinite reflectance ranging from 0.5 to 0.7 Ro and Tmax value of 426°C-436 °C and the TOC values range between 0.8% to 4%.
Keywords: Depositional environment, Devonian, Source rock.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2446621 Organic Agriculture Harmony in Nutrition, Environment and Health: Case Study in Iran
Authors: Sara Jelodarian
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Organic agriculture is a kind of living and dynamic agriculture that was introduced in the early 20th century. The fundamental basis for organic agriculture is in harmony with nature. This version of farming emphasizes removing growth hormones, chemical fertilizers, toxins, radiation, genetic manipulation and instead, integration of modern scientific techniques (such as biologic and microbial control) that leads to the production of healthy food and the preservation of the environment and use of agricultural products such as forage and manure. Supports from governments for the markets producing organic products and taking advantage of the experiences from other successful societies in this field can help progress the positive and effective aspects of this technology, especially in developing countries. This research proves that till 2030, 25% of the global agricultural lands would be covered by organic farming. Consequently Iran, due to its rich genetic resources and various climates, can be a pioneer in promoting organic products. In addition, for sustainable farming, blend of organic and other innovative systems is needed. Important limitations exist to accept these systems, also a diversity of policy instruments will be required to comfort their development and implementation. The paper was conducted to results of compilation of reports, issues, books, articles related to the subject with library studies and research. Likewise we combined experimental and survey to get data.
Keywords: Development, production markets, progress, strategic role, technology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 498620 Preparation and Characterization of Organic Silver Precursors for Conductive Ink
Authors: Wendong Yang, Changhai Wang, Valeria Arrighi
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Low ink sintering temperature is desired for flexible electronics, as it would widen the application of the ink on temperature-sensitive substrates where the selection of silver precursor is very critical. In this paper, four types of organic silver precursors, silver carbonate, silver oxalate, silver tartrate and silver itaconate, were synthesized using an ion exchange method, firstly. Various characterization methods were employed to investigate their physical phase, chemical composition, morphologies and thermal decomposition behavior. It was found that silver oxalate had the ideal thermal property and showed the lowest decomposition temperature. An ink was then formulated by complexing the as-prepared silver oxalate with ethylenediamine in organic solvents. Results show that a favorable conductive film with a uniform surface structure consisting of silver nanoparticles and few voids could be produced from the ink at a sintering temperature of 150 °C.Keywords: Conductive ink, electrical property, film, organic silver.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1091619 Effect of Zeolite on the Decomposition Resistance of Organic Matter in Tropical Soils under Global Warming
Authors: Mai Thanh Truc, Masao Yoshida
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Global temperature had increased by about 0.5oC over the past century, increasing temperature leads to a loss or a decrease of soil organic matter (SOM). Whereas soil organic matter in many tropical soils is less stable than that of temperate soils, and it will be easily affected by climate change. Therefore, conservation of soil organic matter is urgent issue nowadays. This paper presents the effect of different doses (5%, 15%) of Ca-type zeolite in conjunction with organic manure, applied to soil samples from Philippines, Paraguay and Japan, on the decomposition resistance of soil organic matter under high temperature. Results showed that a remain or slightly increase the C/N ratio of soil. There are an increase in percent of humic acid (PQ) that extracted with Na4P2O7. A decrease of percent of free humus (fH) after incubation was determined. A larger the relative color intensity (RF) value and a lower the color coefficient (6logK) value following increasing zeolite rates leading to a higher degrees of humification. The increase in the aromatic condensation of humic acid (HA) after incubation, as indicates by the decrease of H/C and O/C ratios of HA. This finding indicates that the use of zeolite could be beneficial with respect to SOM conservation under global warming condition.Keywords: Global warming, Humic substances, Soil organicmatter, Zeolite.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2206618 Structural Simulation of a 4H-Sic Based Optically Controlled Thyristor Using a GaAs Based Optically Triggered Power Transistor and Its Application to DC-DC Boost Converter
Authors: Srikanta Bose, S.K. Mazumder
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In the present simulation work, an attempt is made to study the switching dynamics of an optically controlled 4HSiC thyristor power semiconductor device with the use of GaAs optically triggered power transistor. The half-cell thyristor has the forward breakdown of 200 V and reverse breakdown of more than 1000 V. The optically controlled thyristor has a rise time of 0.14 μs and fall time of 0.065 μs. The turn-on and turn-off delays are 0.1 μs and 0.06 μs, respectively. In addition, this optically controlled thyristor is used as a control switch for the DC-DC Boost converter. The pn-diode used for the converter has the forward drop of 2.8 V and reverse breakdown of around 400 V.
Keywords: 4H-SiC, Boost converter, Optical triggering, Power semiconductor device, thyristor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1963617 The Effects of Four Organic Cropping Sequences on Soil Phosphorous Cycling and Arbuscular Mycorrhizal Fungi
Authors: R. J. Parham, J. D. Knight
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Organic farmers across Saskatchewan face soil phosphorus (P) shortages. Due to the restriction on inputs in organic systems, farmers rely on crop rotation and naturally-occurring arbuscular mycorrhizal fungi (AMF) for plant P supply. Crop rotation is important for disease, pest, and weed management. Crops that are not colonized by AMF (non-mycorrhizal) can decrease colonization of a following crop. An experiment was performed to quantify soil P cycling in four cropping sequences under organic management and determine if mustard (non-mycorrhizal) was delaying the colonization of subsequent wheat. Soils from the four cropping sequences were measured for inorganic soil P (Pi), AMF spore density (SD), phospholipid fatty acid analysis (PLFA, for AMF biomarker counts), and alkaline phosphatase activity (ALPase, related to AMF metabolic activity). Plants were measured for AMF colonization and P content and uptake of above-ground biomass. A lack of difference in AMF activity indicated that mustard was not depressing colonization. Instead, AMF colonization was largely determined by crop type and crop rotation.
Keywords: Arbuscular mycorrhizal fungi, crop rotation, organic farming, phosphorous, soil microbiology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2110616 Saturated Gain of Doped Multilayer Quantum Dot Semiconductor Optical Amplifiers
Authors: Omar Qasaimeh
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The effect of the number of quantum dot (QD) layers on the saturated gain of doped QD semiconductor optical amplifiers (SOAs) has been studied using multi-population coupled rate equations. The developed model takes into account the effect of carrier coupling between adjacent layers. It has been found that increasing the number of QD layers (K) increases the unsaturated optical gain for K<8 and approximately has no effect on the unsaturated gain for K ≥ 8. Our analysis shows that the optimum ptype concentration that maximizes the unsaturated optical gain of the ground state is NA Ôëê 0.75 ×1018cm-3 . On the other hand, it has been found that the saturated optical gain for both the ground state and the excited state are strong function of both the doping concentration and K where we find that it is required to dope the dots with n-type concentration for very large K at high photon energy.Keywords: doping, multilayer, quantum dot optical amplifier, saturated gain.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1927615 Baking Quality of Hulled Wheat Species in Organic Farming
Authors: P. Konvalina, I. Capouchová, Z. Stehno
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The organic farmers use wider range of crop varieties than the conventional farming. Bread wheat is the most favorite and the most common food crop. The organic bread wheat is usually of worse technological quality. Therefore, it is supposed to be an attractive alternative to the hulled wheat species (einkorn, emmer wheat and spelt). Twenty-five hulled bread wheat varieties and control bread wheat ones were grown on the certified organic parcel in České Budějovice (the Czech Republic) between 2009 and 2012. Their baking quality was measured and evaluated with standard methods, and in accordance with ICC. The results have shown that the grain of hulled wheat varieties contain a lot of proteins in grains (up to 18 percent); even the organic hulled bread wheat varieties are characterized by such good baking quality. Einkorn and emmer wheat are of worse technological quality of proteins (low values of gluten index and Zeleny test), which is a disadvantage of these two wheat species. On the other hand, spelt wheat is of better technological quality and is similar to the control bread wheat varieties. Mixtures consisting of bread wheat, among others, are considered good alternatives; they may contribute to wider range of use of the hulled wheat species. It is one of the possibilities which may increase the proportion of proteins in bread wheat grains; the nutrition-rich hulled wheat grains may be also used in such way at the same time.
Keywords: Baking quality, organic farming, einkorn, emmer wheat, spelt.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1878614 Investigation in Physically-Chemical Parameters of in Latvia Harvested Conventional and Organic Triticale Grains
Authors: Solvita Kalnina, Tatjana Rakcejeva, Daiga Kunkulberga, Anda Linina
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Triticale is a manmade hybrid of wheat and rye that carries the A and B genome of durum wheat and the R genome of rye. In the scientific literature information about in Latvia harvested organic and conventional triticale grain physically-chemical composition was not found in general. Therefore, the main purpose of the current research was to investigate physically-chemical parameters of in Latvia harvested organic and convectional triticale grains. The research was accomplished on in Year 2012 from State Priekuli Plant Breeding Institute (Latvia) harvested organic and conventional triticale grains: “Dinaro”, “9403-97”, “9405-23” and “9402-3”. In the present research significant differences in chemical composition between organic and conventional triticale grains harvested in Latvia was found. It is necessary to mention that higher 1000 grain weight, bulk density and gluten index was obtained for conventional and organic triticale grain variety “9403-97”. However higher falling number, gluten and protein content was obtained for triticale grain variety “9405-23”.
Keywords: Physically-chemical parameters, technological properties, triticale grains.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2684613 Loss Analysis of Half Bridge DC-DC Converters in High-Current and Low-Voltage Applications
Authors: A. Faruk Bakan, İsmail Aksoy, Nihan Altintaş
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In this paper, half bridge DC-DC converters with transformer isolation presented in the literature are analyzed for highcurrent and low-voltage applications under the same operation conditions, and compared in terms of losses and efficiency. The conventional and improved half-bridge DC-DC converters are simulated, and current and voltage waveforms are obtained for input voltage Vdc=500V, output current IO=450A, output voltage VO=38V and switching frequency fS=20kHz. IGBTs are used as power semiconductor switches. The power losses of the semiconductor devices are calculated from current and voltage waveforms. From simulation results, it is seen that the capacitor switched half bridge converter has the best efficiency value, and can be preferred at high power and high frequency applications.Keywords: Isolated half bridge DC-DC converter, high-current low-voltage applications, soft switching, high efficiency.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5178612 Development of Quasi-Two-Dimensional Nb2O5 for Functional Electrodes of Advanced Electrochemical Systems
Authors: S. Zhuiykov, E. Kats
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In recent times there has been a growing interest in the development of quasi-two-dimensional niobium pentoxide (Nb2O5) as a semiconductor for the potential electronic applications such as capacitors, filtration, dye-sensitised solar cells and gas sensing platforms. Therefore once the purpose is established, Nb2O5 can be prepared in a number of nano- and sub-micron-structural morphologies that include rods, wires, belts and tubes. In this study films of Nb2O5 were prepared on gold plated silicon substrate using spin-coating technique and subsequently by mechanical exfoliation. The reason this method was employed was to achieve layers of less than 15nm in thickness. The sintering temperature of the specimen was 800oC. The morphology and structural characteristics of the films were analyzed by Atomic Force Microscopy (AFM), Raman Spectroscopy, X-ray Photoelectron Spectroscopy (XPS).Keywords: Mechanical exfoliation, niobium pentoxide, quazitwo- dimensional, semiconductor, sol-gel, spin-coating, two dimensional semiconductors.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2395611 Optimization of Process Parameters Affecting Biogas Production from Organic Fraction of Municipal Solid Waste via Anaerobic Digestion
Authors: Sajeena Beevi. B, Jose P. P., G. Madhu
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The aim of this study was to obtain the optimal conditions for biogas production from anaerobic digestion of organic fraction of municipal solid waste (OFMSW) using response surface methodology (RSM). The parameters studied were initial pH, substrate concentration and total organic carbon (TOC). The experimental results showed that the linear model terms of initial pH and substrate concentration and the quadratic model terms of the substrate concentration and TOC had significant individual effect (p < 0.05) on biogas yield. However, there was no interactive effect between these variables (p > 0.05). The highest level of biogas produced was 53.4 L/Kg VS at optimum pH, substrate concentration and total organic carbon of 6.5, 99gTS/L and 20.32 g/L respectively.
Keywords: Anaerobic Digestion, Biogas, Optimization, Response Surface Methodology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4773610 Modeling and Performance Evaluation of Three Power Generation and Refrigeration Energy Recovery Systems from Thermal Loss of a Diesel Engine in Different Driving Conditions
Authors: H. Golchoobian, M. H. Taheri, S. Saedodin, A. Sarafraz
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This paper investigates the possibility of using three systems of organic Rankine auxiliary power generation, ejector refrigeration and absorption to recover energy from a diesel car. The analysis is done for both urban and suburban driving modes that vary from 60 to 120 km/h. Various refrigerants have also been used for organic Rankine and Ejector refrigeration cycles. The capacity was evaluated by Organic Rankine Cycle (ORC) system in both urban and suburban conditions for cyclopentane and ammonia as refrigerants. Also, for these two driving plans, produced cooling by absorption refrigeration system under variable ambient temperature conditions and in ejector refrigeration system for R123, R134a and R141b refrigerants were investigated.
Keywords: Absorption system, diesel engine, ejector refrigeration, energy recovery, organic Rankine cycle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 710609 An Exploration on Competency-Based Curricula in Integrated Circuit Design
Authors: Chih Chin Yang, Chung Shan Sun
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In this paper the relationships between professional competences and school curriculain IC design industry are explored. The semi-structured questionnaire survey and focus group interview is the research method. Study participants are graduates of microelectronics engineering professional departments who are currently employed in the IC industry. The IC industries are defined as the electronic component manufacturing industry and optical-electronic component manufacturing industry in the semiconductor industry and optical-electronic material devices, respectively. Study participants selected from IC design industry include IC engineering and electronic & semiconductor engineering. The human training with IC design professional competence in microelectronics engineering professional departments is explored in this research. IC professional competences of human resources in the IC design industry include general intelligence and professional intelligence.
Keywords: IC design, curricula, competence, task, duty.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1495608 Mechanisms Involved In Organic Solvent Resistance in Gram-Negative Bacteria
Authors: M. M. Lâzâroaie
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The high world interest given to the researches concerning the study of moderately halophilic solvent-tolerant bacteria isolated from marine polluted environments is due to their high biotechnological potential, and also to the perspective of their application in different remediation technologies. Using enrichment procedures, I isolated two moderately halophilic Gram-negative bacterial strains from seawater sample, which are tolerant to organic solvents. Cell tolerance, adhesion and cells viability of Aeromonas salmonicida IBBCt2 and Pseudomonas aeruginosa IBBCt3 in the presence of organic solvents depends not only on its physicochemical properties and its concentration, but also on the specific response of the cells, and the cellular response is not the same for these bacterial strains. n-hexane, n-heptane, propylbenzene, with log POW between 3.69 and 4.39, were less toxic for Aeromonas salmonicida IBBCt2 and Pseudomonas aeruginosa IBBCt3, compared with toluene, styrene, xylene isomers and ethylbenzene, with log POW between 2.64 and 3.17. The results indicated that Aeromonas salmonicida IBBCt2 is more susceptible to organic solvents than Pseudomonas aeruginosa IBBCt3. The mechanisms underlying solvent tolerance (e.g., the existance of the efflux pumps) in Aeromonas salmonicida IBBCt2 and Pseudomonas aeruginosa IBBCt3 it was also studied.
Keywords: bacteria, mechanisms, organic solvent, resistance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1977607 Deriving Causal Explanation from Qualitative Model Reasoning
Authors: Alicia Y. C. Tang, Sharifuddin M. Zain, Noorsaadah A. Rahman, Rukaini Abdullah
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This paper discusses a qualitative simulator QRiOM that uses Qualitative Reasoning (QR) technique, and a process-based ontology to model, simulate and explain the behaviour of selected organic reactions. Learning organic reactions requires the application of domain knowledge at intuitive level, which is difficult to be programmed using traditional approach. The main objective of QRiOM is to help learners gain a better understanding of the fundamental organic reaction concepts, and to improve their conceptual comprehension on the subject by analyzing the multiple forms of explanation generated by the software. This paper focuses on the generation of explanation based on causal theories to explicate various phenomena in the chemistry subject. QRiOM has been tested with three classes problems related to organic chemistry, with encouraging results. This paper also presents the results of preliminary evaluation of QRiOM that reveal its explanation capability and usefulness.Keywords: Artificial intelligence, explanation, ontology, organicreactions, qualitative reasoning, QPT.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1647606 n-Butanol as an Extractant for Lactic Acid Recovery
Authors: Kanungnit Chawong, Panarat Rattanaphanee
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Extraction of lactic acid from aqueous solution using n-butanol as an extractant was studied. Effect of mixing time, pH of the aqueous solution, initial lactic acid concentration, and volume ratio between the organic and the aqueous phase were investigated. Distribution coefficient and degree of lactic acid extraction was found to increase when the pH of aqueous solution was decreased. The pH Effect was substantially pronounced at pH of the aqueous solution less than 1. Initial lactic acid concentration and organic-toaqueous volume ratio appeared to have positive effect on the distribution coefficient and the degree of extraction. Due to the nature of n-butanol that is partially miscible in water, incorporation of aqueous solution into organic phase was observed in the extraction with large organic-to-aqueous volume ratio.
Keywords: Lactic acid, liquid-liquid extraction, n-Butanol, Solvating extractant.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3170605 Model Predictive Control Using Thermal Inputs for Crystal Growth Dynamics
Authors: Takashi Shimizu, Tomoaki Hashimoto
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Recently, crystal growth technologies have made progress by the requirement for the high quality of crystal materials. To control the crystal growth dynamics actively by external forces is useuful for reducing composition non-uniformity. In this study, a control method based on model predictive control using thermal inputs is proposed for crystal growth dynamics of semiconductor materials. The control system of crystal growth dynamics considered here is governed by the continuity, momentum, energy, and mass transport equations. To establish the control method for such thermal fluid systems, we adopt model predictive control known as a kind of optimal feedback control in which the control performance over a finite future is optimized with a performance index that has a moving initial time and terminal time. The objective of this study is to establish a model predictive control method for crystal growth dynamics of semiconductor materials.Keywords: Model predictive control, optimal control, crystal growth, process control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 829604 Phase Equilibrium of Volatile Organic Compounds in Polymeric Solvents Using Group Contribution Methods
Authors: E. Muzenda
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Group contribution methods such as the UNIFAC are of major interest to researchers and engineers involved synthesis, feasibility studies, design and optimization of separation processes as well as other applications of industrial use. Reliable knowledge of the phase equilibrium behavior is crucial for the prediction of the fate of the chemical in the environment and other applications. The objective of this study was to predict the solubility of selected volatile organic compounds (VOCs) in glycol polymers and biodiesel. Measurements can be expensive and time consuming, hence the need for thermodynamic models. The results obtained in this study for the infinite dilution activity coefficients compare very well those published in literature obtained through measurements. It is suggested that in preliminary design or feasibility studies of absorption systems for the abatement of volatile organic compounds, prediction procedures should be implemented while accurate fluid phase equilibrium data should be obtained from experiment.Keywords: Volatile organic compounds, Prediction, Phaseequilibrium, Environmental, Infinite dilution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2025603 Role of Organic Wastewater Constituents in Iron Redox Cycling for Ferric Sludge Reuse in the Fenton-Based Treatment
Authors: J. Bolobajev, M. Trapido, A. Goi
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The practical application of the Fenton-based treatment method for organic compounds-contaminated water purification is limited mainly because of the large amount of ferric sludge formed during the treatment, where ferrous iron (Fe(II)) is used as the activator of the hydrogen peroxide oxidation processes. Reuse of ferric sludge collected from clarifiers to substitute Fe(II) salts allows reducing the total cost of Fenton-type treatment technologies and minimizing the accumulation of hazardous ferric waste. Dissolution of ferric iron (Fe(III)) from the sludge to liquid phase at acidic pH and autocatalytic transformation of Fe(III) to Fe(II) by phenolic compounds (tannic acid, lignin, phenol, catechol, pyrogallol and hydroquinone) added or present as water/wastewater constituents were found to be essentially involved in the Fenton-based oxidation mechanism. Observed enhanced formation of highly reactive species, hydroxyl radicals, resulted in a substantial organic contaminant degradation increase. Sludge reuse at acidic pH and in the presence of ferric iron reductants is a novel strategy in the Fenton-based treatment application for organic compounds-contaminated water purification.
Keywords: Ferric sludge reuse, ferric iron reductant, water treatment, organic pollutant.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1669602 Studies on Storage Behavior of Cabbage Head as Influenced by Organic Amendments and Inorganic Fertilizers
Authors: Ranjit Chatterjee, P. K. Paul
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The influence of organic amendments and inorganic fertilizers on cabbage head was investigated to determine their effect on storage behavior and organoleptic quality. Field cabbage was raised by combining fourteen different treatments comprising of organic amendments and inorganic fertilizers at different levels. The result showed that nutrient schedule of the crop significantly influenced the physiological loss in weight (PLW) and organoleptic quality of cabbage head and judicious selection of nutrient combination can extend the storage life and reduce the post harvest detoriaration of head. The nutrient schedule comprising of higher level of FYM (16 t ha-1) along with 75% of recommended inorganic fertilizers in conjugation with seedling inoculation of biofertilizer emerged as potential nutrient source for improving storage life, marketability and maintaining nutritional and organoleptic quality under ambient storage condition.
Keywords: Cabbage head, Organic amendments, Organoleptic quality, Physiological loss in weight (PLW).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2063601 A Design of the Organic Rankine Cycle for the Low Temperature Waste Heat
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A presentation of the design of the Organic Rankine cycle (ORC) with heat regeneration and superheating processes is a subject of this paper. The maximum temperature level in the ORC is considered to be 110°C and the maximum pressure varies up to 2.5MPa. The selection process of the appropriate working fluids, thermal design and calculation of the cycle and its components are described. With respect to the safety, toxicity, flammability, price and thermal cycle efficiency, the working fluid selected is R134a. As a particular example, the thermal design of the condenser used for the ORC engine with a theoretical thermal power of 179 kW was introduced. The minimal heat transfer area for a completed condensation was determined to be approximately 520m2.
Keywords: Organic Rankine Cycle, thermal efficiency, working fluids.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4058600 Energy Recovery Potential from Food Waste and Yard Waste in New York and Montréal
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Landfilling of organic waste is still the predominant waste management method in the USA and Canada. Strategic plans for waste diversion from landfills are needed to increase material recovery and energy generation from waste. In this paper, we carried out a statistical survey on waste flow in the two cities New York and Montréal and estimated the energy recovery potential for each case. Data collection and analysis of the organic waste (food waste, yard waste, etc.), paper and cardboard, metal, glass, plastic, carton, textile, electronic products and other materials were done based on the reports published by the Department of Sanitation in New York and Service de l'Environnement in Montréal. In order to calculate the gas generation potential of organic waste, Buswell equation was used in which the molar mass of the elements was calculated based on their atomic weight and the amount of organic waste in New York and Montréal. Also, the higher and lower calorific value of the organic waste (solid base) and biogas (gas base) were calculated. According to the results, only 19% (598 kt) and 45% (415 kt) of New York and Montréal waste were diverted from landfills in 2017, respectively. The biogas generation potential of the generated food waste and yard waste amounted to 631 million m3 in New York and 173 million m3 in Montréal. The higher and lower calorific value of food waste were 3482 and 2792 GWh in New York and 441 and 354 GWh in Montréal, respectively. In case of yard waste, they were 816 and 681 GWh in New York and 636 and 531 GWh in Montréal, respectively. Considering the higher calorific value, this amount would mean a contribution of around 2.5% energy in these cities.
Keywords: Energy recovery, organic waste, urban energy modelling with INSEL, waste flow.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 944599 Generating Qualitative Causal Graph using Modeling Constructs of Qualitative Process Theory for Explaining Organic Chemistry Reactions
Authors: Alicia Y. C. Tang, Rukaini Abdullah, Sharifuddin M. Zain, Noorsaadah A. Rahman
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This paper discusses the causal explanation capability of QRIOM, a tool aimed at supporting learning of organic chemistry reactions. The development of the tool is based on the hybrid use of Qualitative Reasoning (QR) technique and Qualitative Process Theory (QPT) ontology. Our simulation combines symbolic, qualitative description of relations with quantity analysis to generate causal graphs. The pedagogy embedded in the simulator is to both simulate and explain organic reactions. Qualitative reasoning through a causal chain will be presented to explain the overall changes made on the substrate; from initial substrate until the production of final outputs. Several uses of the QPT modeling constructs in supporting behavioral and causal explanation during run-time will also be demonstrated. Explaining organic reactions through causal graph trace can help improve the reasoning ability of learners in that their conceptual understanding of the subject is nurtured.Keywords: Qualitative reasoning, causal graph, organicreactions, explanation, QPT, modeling constructs.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1418598 Reutilization of Organic and Peat Soils by Deep Cement Mixing
Authors: Bee-Lin Tang, Ismail Bakar, Chee - Ming Chan
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Limited infrastructure development on peats and organic soils is a serious geotechnical issues common to many countries of the world especially Malaysia which distributed 1.5 mill ha of those problematic soil. These soils have high water content and organic content which exhibit different mechanical properties and may also change chemically and biologically with time. Constructing structures on peaty ground involves the risk of ground failure and extreme settlement. Nowdays, much efforts need to be done in making peatlands usable for construction due to increased landuse. Deep mixing method employing cement as binders, is generally used as measure again peaty/ organic ground failure problem. Where the technique is widely adopted because it can improved ground considerably in a short period of time. An understanding of geotechnical properties as shear strength, stiffness and compressibility behavior of these soils was requires before continues construction on it. Therefore, 1- 1.5 meter peat soil sample from states of Johor and an organic soil from Melaka, Malaysia were investigated. Cement were added to the soil in the pre-mixing stage with water cement ratio at range 3.5,7,14,140 for peats and 5,10,30 for organic soils, essentially to modify the original soil textures and properties. The mixtures which in slurry form will pour to polyvinyl chloride (pvc) tube and cured at room temperature 250C for 7,14 and 28 days. Laboratory experiments were conducted including unconfined compressive strength and bender element , to monitor the improved strength and stiffness of the 'stabilised mixed soils'. In between, scanning electron miscroscopic (SEM) were observations to investigate changes in microstructures of stabilised soils and to evaluated hardening effect of a peat and organic soils stabilised cement. This preliminary effort indicated that pre-mixing peat and organic soils contributes in gaining soil strength while help the engineers to establish a new method for those problematic ground improvement in further practical and long term applications.Keywords: peat soils, organic soils, cement stabilisation, strength, stiffness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3258597 Alternative Approach toward Waste Treatment: Biodrying for Solid Waste in Malaysia
Authors: Nurul' Ain Ab Jalil, Hassan Basri
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This paper reviews the objectives, methods and results of previous studies on biodrying of solid waste in several countries. Biodrying of solid waste is a novel technology in developing countries such as in Malaysia where high moisture content in organic waste makes the segregation process for recycling purposes complicated and diminishes the calorific value for the use of fuel source. In addition, the high moisture content also encourages the breeding of vectors and disease-bearing animals. From the laboratory results, the average moisture content of organic waste, paper, plastics and metals are 58.17%, 37.93%, 29.79% and 1.03% respectively for UKM campus. Biodrying of solid waste is a simple method of waste treatment as well as a cost-efficient technology to dry the solid waste. The process depends on temperature monitoring and air flow control along with the natural biodegradable process of organic waste. This review shows that the biodrying of solid waste method has high potential in treatment and recycling of solid waste, be useful for biodrying study and implementation in Malaysia.
Keywords: Biodrying of solid waste, Organic waste, Fuel source.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1977596 Influence of Measurement System on Negative Bias Temperature Instability Characterization: Fast BTI vs Conventional BTI vs Fast Wafer Level Reliability
Authors: Vincent King Soon Wong, Hong Seng Ng, Florinna Sim
Abstract:
Negative Bias Temperature Instability (NBTI) is one of the critical degradation mechanisms in semiconductor device reliability that causes shift in the threshold voltage (Vth). However, thorough understanding of this reliability failure mechanism is still unachievable due to a recovery characteristic known as NBTI recovery. This paper will demonstrate the severity of NBTI recovery as well as one of the effective methods used to mitigate, which is the minimization of measurement system delays. Comparison was done in between two measurement systems that have significant differences in measurement delays to show how NBTI recovery causes result deviations and how fast measurement systems can mitigate NBTI recovery. Another method to minimize NBTI recovery without the influence of measurement system known as Fast Wafer Level Reliability (FWLR) NBTI was also done to be used as reference.Keywords: Fast vs slow BTI, Fast wafer level reliability, Negative bias temperature instability, NBTI measurement system, metal-oxide-semiconductor field-effect transistor, MOSFET, NBTI recovery, reliability.
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