Search results for: harvesting in high altitudes
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 19899

Search results for: harvesting in high altitudes

19419 Computational Investigation of Gas-Solid Flow in High Pressure High Temperature Filter

Authors: M. H. Alhajeri, Hamad M. Alhajeri, A. H. Alenezi

Abstract:

This paper reports a Computational Fluid Dynamics (CFD) investigation for a high-temperature high-pressure filtration (ceramic candle filter). However, parallel flow to the filter is considered in this study. Different face (filtration) velocities are examined using the CFD code, FLUENT. Different sizes of particles are tracked through the domain to find the height at which the particles will impinge on the filter surface. Furthermore, particle distribution around the filter (or filter cake) is studied to design efficient cleaning mechanisms. Gravity effect to the particles with various inlet velocities and pressure drop are both considered. In the CFD study, it is found that the gravity influence should not be ignored if the particle sizes exceed 1 micron.

Keywords: fluid flow, CFD, filtration, HTHP

Procedia PDF Downloads 191
19418 The Impact of Digital Inclusive Finance on the High-Quality Development of China's Export Trade

Authors: Yao Wu

Abstract:

In the context of financial globalization, China has put forward the policy goal of high-quality development, and the digital economy, with its advantage of information resources, is driving China's export trade to achieve high-quality development. Due to the long-standing financing constraints of small and medium-sized export enterprises, how to expand the export scale of small and medium-sized enterprises has become a major threshold for the development of China's export trade. This paper firstly adopts the hierarchical analysis method to establish the evaluation system of high-quality development of China's export trade; secondly, the panel data of 30 provinces in China from 2011 to 2018 are selected for empirical analysis to establish the impact model of digital inclusive finance on the high-quality development of China's export trade; based on the analysis of heterogeneous enterprise trade model, a mediating effect model is established to verify the mediating role of credit constraint in the development of high-quality export trade in China. Based on the above analysis, this paper concludes that inclusive digital finance, with its unique digital and inclusive nature, alleviates the credit constraint problem among SMEs, enhances the binary marginal effect of SMEs' exports, optimizes their export scale and structure, and promotes the high-quality development of regional and even national export trade. Finally, based on the findings of this paper, we propose insights and suggestions for inclusive digital finance to promote the high-quality development of export trade.

Keywords: digital inclusive finance, high-quality development of export trade, fixed effects, binary marginal effects

Procedia PDF Downloads 74
19417 A Prediction of Electrical Cost for High-Rise Building Construction

Authors: Picha Sriprachan

Abstract:

The increase in electricity prices affects the cost of high-rise building construction. The objectives of this research are to study the electrical cost, trend of electrical cost and to forecast electrical cost of high-rise building construction. The methods of this research are: 1) to study electrical payment formats, cost data collection methods, and the factors affecting electrical cost of high-rise building construction, 2) to study the quantity and trend of cumulative percentage of the electrical cost, and 3) to forecast the electrical cost for different types of high-rise buildings. The results of this research show that the average proportion between electrical cost and the value of the construction project is 0.87 percent. The proportion of electrical cost for residential, office and commercial, and hotel buildings are closely proportional. If construction project value increases, the proportion of electrical cost and the value of the construction project will decrease. However, there is a relationship between the amount of electrical cost and the value of the construction project. During the structural construction phase, the amount of electrical cost will increase and during structural and architectural construction phase, electrical cost will be maximum. The cumulative percentage of the electrical cost is related to the cumulative percentage of the high-rise building construction cost in the same direction. The amount of service space of the building, number of floors and the duration of the construction affect the electrical cost of construction. The electrical cost of construction forecasted by using linear regression equation is close to the electrical cost forecasted by using the proportion of electrical cost and value of the project.

Keywords: high-rise building construction, electrical cost, construction phase, architectural phase

Procedia PDF Downloads 369
19416 Femtocell Stationed Flawless Handover in High Agility Trains

Authors: S. Dhivya, M. Abirami, M. Farjana Parveen, M. Keerthiga

Abstract:

The development of high-speed railway makes people’s lives more and more convenient; meanwhile, handover is the major problem on high-speed railway communication services. In order to overcome that drawback the architecture of Long-Term Evolution (LTE) femtocell networks is used to improve network performance, and the deployment of a femtocell is a key for bandwidth limitation and coverage issues in conventional mobile network system. To increase the handover performance this paper proposed a multiple input multiple output (MIMO) assisted handoff (MAHO) algorithm. It is a technique used in mobile telecom to transfer a mobile phone to a new radio channel with stronger signal strength and improved channel quality.

Keywords: flawless handover, high-speed train, home evolved Node B, LTE, mobile femtocell, RSS

Procedia PDF Downloads 456
19415 Revealing the Feature of Mind Wandering on People with High Creativity and High Mental Health through Experience Sampling Method

Authors: A. Yamaoka, S. Yukawa

Abstract:

Mind wandering is a mental phenomenon of drifting away from a current task or external environment toward inner thought. This research examines the feature of mind wandering which people who have high creativity and high mental health engage in because it is expected that mind wandering which such kind of people engage in may not induce negative affect, although it can improve creativity. Sixty-seven participants were required to complete questionnaires which measured their creativity and mental health. After that, researchers conducted experience sampling method and measured the details of their mind wandering and the situation when mind wandering was generated in daily life for three days. The result showed that high creative people and high mental health people more think about positive things during mind wandering and less think about negative things. In further research, researchers will examine how to induce positive thought during mind wandering and how to inhibit negative thought during mind wandering. Doing so will contribute to improve creative problem solving without generation of negative affect.

Keywords: creativity, experience sampling method, mental health, mind wandering

Procedia PDF Downloads 157
19414 2023 Targets of the Republic of Turkey State Railways

Authors: Hicran Açıkel, Hüseyin Arak, D. Ali Açıkel

Abstract:

Train or high-speed train is a land transportation vehicle, which is safe and offers passengers flight-like comfort while it is preferred for busy lines with respect to passengers. In this study, TCDD’s (Turkish State Railroads Company) targets for the year of 2023, the planned high-speed train lines, improvements, which are considered for the existing lines, and achievability of these targets are examined.

Keywords: train, high-speed train, TCDD, transportation

Procedia PDF Downloads 223
19413 Simple Modified Method for DNA Isolation from Lyophilised Cassava Storage Roots (Manihot esculenta Crantz.)

Authors: P. K. Telengech, K. Monjero, J. Maling’a, A. Nyende, S. Gichuki

Abstract:

There is need to identify an efficient protocol for use in extraction of high quality DNA for purposes of molecular work. Cassava roots are known for their high starch content, polyphenols and other secondary metabolites which interfere with the quality of the DNA. These factors have negative interference on the various methodologies for DNA extraction. There is need to develop a simple, fast and inexpensive protocol that yields high quality DNA. In this improved Dellaporta method, the storage roots are lyophilized to reduce the water content; the extraction buffer is modified to eliminate the high polyphenols, starch and wax. This simple protocol was compared to other protocols intended for plants with similar secondary metabolites. The method gave high yield (300-950ng) and pure DNA for use in PCR analysis. This improved Dellaporta protocol allows isolation of pure DNA from starchy cassava storage roots.

Keywords: cassava storage roots, dellaporta, DNA extraction, lyophilisation, polyphenols secondary metabolites

Procedia PDF Downloads 337
19412 Improvement of the Calciferous Minerals Floatability through the Application of High-Power Electromagnetic Pulses

Authors: Valentine A. Chanturiya, Igor Zh. Bunin, Maria V. Ryazantseva

Abstract:

The modification of structural and chemical properties of fluorite, scheelite and calcite under the impact of high-power electromagnetic pulses (HPEMP-treatment) were studied with the help of adsorption of acid-base indicators and atomic – force microscopy (AFM). The HPEMP-treatment during the space of 30 seconds resulted in the intensification of fluorite surface the electron-donating ability and acceptor properties of calcite and scheelite surfaces. High-power electromagnetic treatment of the single minerals resulted in the improvement of the calciferous minerals floatability. The rising of the scheelite recovery is 10 – 12%, fluorite – 5 – 6%, calcite – 7 – 8%.

Keywords: calcite, fluorite, scheelite, high power electromagnetic pulses, floatability

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19411 High Performance of Square GAA SOI MOSFET Using High-k Dielectric with Metal Gate

Authors: Fatima Zohra Rahou, A. Guen Bouazza, B. Bouazza

Abstract:

Multi-gate SOI MOSFETs has shown better results in subthreshold performances. The replacement of SiO2 by high-k dielectric can fulfill the requirements of Multi-gate MOSFETS with a scaling trend in device dimensions. The advancement in fabrication technology has also boosted the use of different high -k dielectric materials as oxide layer at different places in MOSFET structures. One of the most important multi-gate structures is square GAA SOI MOSFET that is a strong candidate for the next generation nanoscale devices; show an even stronger control of short channel effects. In this paper, GAA SOI MOSFET structure with using high -k dielectrics materials Al2O3 (k~9), HfO2 (k~20), La2O3 (k~30) and metal gate TiN are simulated by using 3-D device simulator DevEdit and Atlas of SILVACO TCAD tools. Square GAA SOI MOSFET transistor with High-k HfO2 gate dielectrics and TiN metal gate exhibits significant improvements performances compared to Al2O3 and La2O3 dielectrics for the same structure. Simulation results of GAA SOI MOSFET transistor with HfO2 dielectric show the increase in saturation current and Ion/Ioff ratio while leakage current, subthreshold slope and DIBL effect are decreased.

Keywords: technology SOI, short-channel effects (SCEs), multi-gate SOI MOSFET, square GAA SOI MOSFET, high-k dielectric, Silvaco software

Procedia PDF Downloads 247
19410 Study of Self-Assembled Photocatalyst by Metal-Terpyridine Interactions in Polymer Network

Authors: Dong-Cheol Jeong, Jookyung Lee, Yu Hyeon Ro, Changsik Song

Abstract:

The design and synthesis of photo-active polymeric systems are important in regard to solar energy harvesting and utilization. In this study, we synthesized photo-active polymer, thin films, and polymer gel via iterative self-assembly using reversible metal-terpyridine (M-tpy) interactions. The photocurrent generated in the polymeric thin films with Zn(II) was much higher than those of other films. Apparent diffusion rate constant (kapp) was measured for the electron hopping process via potential-step chronoamperometry. As a result, the kapp for the polymeric thin films with Zn(II) was almost two times larger than those with other metal ions. We found that the anodic photocurrents increased with the inclusion of the multi-walled carbon nanotube (MWNT) layer. Inclusion of MWNTs can provide efficient electron transfer pathways. In addition, polymer gel based on interactions between terpyridine and metal ions was shown the photocatalytic activity. Interestingly, in the Mg-terpyridine gel, the reaction rate of benzylamine to imine photo-oxidative coupling was faster than Fe-terpyridine gel because the Mg-terpyridine gel has two steps electron transfer pathway but Fe-terpyridine gel has three steps electron transfer pathway.

Keywords: terpyridine, photocatalyst, self-assebly, metal-ligand

Procedia PDF Downloads 291
19409 The Role of Poling Protocol on Augmentation of Magnetoelectricity in BCZT/NZFO Layered Composites

Authors: Pankhuri Bansal, Sanjeev Kumar

Abstract:

We examined the exotic role of electrical poling of layered BCZT-NZFO bulk composite for sustainable advancement of magnetoelectric (ME) technology. Practically, it seems quite difficult to access the full potential of ME composites due to their weak ME coupling performances. Using a standard poling protocol, we successfully deployed the coupling performance of laminated ME composite, comprised of a ferroelectric (FE) layer of BCZT and a ferrite layer of NZFO. However, the ME coupling constant of laminated composite is optimized by lowering the volume fraction of the FE component to strengthen the mechanical strain in the piezoelectric layer while fixing the thickness of the magnetostrictive ferrite layer. Here, we employed systematic zero field cooled (ZFC) and field cooled (FC) electrical poling protocol on morphotropic phase boundary (MPB) based BCZT composition, well-appreciated for it’s remarkable electromechanical activity. We report a record augmentation in magnetoelectric coupling as a consequence of a prudent field-cooled poling mechanism. On the basis of our findings, we emphasize that the degree of magnetoelectricity may be significantly improved for the miniaturization of efficient devices via proper execution of the poling technique.

Keywords: magnetoelectric, lead-free, ferroelctric, ferromagnetic, energy harvesting

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19408 Substitution of Formaldehyde in Phenolic Resins with Innovative and Bio-Based Vanillin Derived Compounds

Authors: Sylvain Caillol, Ghislain David

Abstract:

Phenolic resins are industrially used in a wide range of applications from commodity and construction materials to high-technology aerospace industry. They are mainly produced from the reaction between phenolic compounds and formaldehyde. Nevertheless, formaldehyde is a highly volatile and hazardous compound, classified as a Carcinogenic, Mutagenic and Reprotoxic chemical (CMR). Vanillin is a bio-based and non-toxic aromatic aldehyde compound obtained from the abundant lignin resources. Also, its aromaticity is very interesting for the synthesis of phenolic resins with high thermal stability. However, because of the relatively low reactivity of its aldehyde function toward phenolic compounds, it has never been used to synthesize phenolic resins. We developed innovative functionalization reactions and designed new bio-based aromatic aldehyde compounds from vanillin. Those innovative compounds present improved reactivity toward phenolic compounds compared to vanillin. Moreover, they have target structures to synthesize highly cross-linked phenolic resins with high aromatic densities. We have obtained phenolic resins from substituted vanillin, thus without the use of any aldehyde compound classified as CMR. The analytical tests of the cured resins confirmed that those bio-based resins exhibit high levels of performance with high thermal stability and high rigidity properties

Keywords: phenolic resins, formaldehyde-free, vanillin, bio-based, non-toxic

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19407 Platform Development for Vero Cell Culture on Microcarriers Using Dissociation-Reassociation Method

Authors: Thanunthon Bowornsakulwong, Charukorn Charukarn, Franck Courtes, Panit Kitsubun, Lalintip Horcharoen

Abstract:

Vero cell is a continuous cell line that is widely used for the production of viral vaccines. However, due to its adherent characteristic, scaling up strategy in large-scale production remains complicated and thus limited. Consequently, suspension-like Vero cell culture processes based on microcarriers have been introduced and employed while also providing increased surface area per volume unit. However, harvesting Vero cells from microcarriers is a huge challenge due to difficulties in cells detaching, lower recovery yield, time-consuming and dissociation agent carry-over. To overcome these problems, we developed a dissociation-association platform technology for detaching and re-attaching cells during subculturing from microcarriers to microcarriers, which will be conveniently applied to seed trains strategies in large scale bioreactors. Herein, Hillex-2 was used to culture Vero cells in serum-containing media using spinner flasks as a scale-down model. The overall confluency of cells on microcarriers was observed using inverted microscope, and the sample cells were daily detached in order to obtain the kinetics data. The metabolites consumption and by-products formation were determined by Nova Biomedical BioprofileFlex.

Keywords: dissociation-reassociation, microcarrier, scale up, Vero cell

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19406 High-Frequency Full-Bridge Isolated DC-DC Converter for Fuel Cell Power Generation Systems

Authors: Nabil A. Ahmed

Abstract:

DC-DC converters are necessary to interface low-voltage fuel cell power generation systems to a higher voltage DC bus system. A system and method for generating a regulated output power from fuel cell power generation systems is proposed in this paper, this includes a soft-switching isolated DC-DC converter to reduce the idling and circulating currents. The system incorporates a high-frequency center tap transformer link DC-DC converter using secondary-side soft switching control. Snubber capacitors including the parasitic capacitance of the switching devices and the transformer leakage inductance are utilized to achieve zero-voltage switching (ZVS) in the primary side of the high-frequency transformer. Therefore, no extra resonant components are required for ZVS. The inherent soft-switching capability allows high power density, efficient power conversion, and compact packaging. A prototype rated at 6.5 kW is proposed and simulated. Simulation results confirmed a wide range of soft-switching operation and consequently high conversion efficiency will be achieved.

Keywords: secondary-side, phase-shift, high-frequency transformer, zero voltage, zero current, soft switching operation, switching losses

Procedia PDF Downloads 289
19405 Wet Extraction of Lutein and Lipids from Microalga by Quantitative Determination of Polarity

Authors: Mengyue Gong, Xinyi Li, Amarjeet Bassi

Abstract:

Harvesting by-products while recovering biodiesel is considered a potentially valuable approach to increase the market feasibility of microalgae industry. Lutein is a possible by-product from microalgae that promotes eye health. The extraction efficiency and the expensive drying process of wet algae represent the major challenges for the utilization of microalgae biomass as a feedstock for lipids, proteins, and carotenoids. A wet extraction method was developed to extract lipids and lutein from microalga Chlorella vulgaris. To evaluate different solvent (mixtures) for the extraction, a quantitative analysis was established based on the polarity of solvents using Nile Red as the polarity (ETN) indicator. By the choice of binary solvent system then adding proper amount of water to achieve phase separation, lipids and lutein can be extracted simultaneously. Some other parameters for lipids and lutein production were also studied including saponification time, temperature, choice of alkali, and pre-treatment methods. The extraction efficiency with wet algae was compared with dried algae and shown better pigment recovery. The results indicated that the product pattern in each extracted phase was polarity dependent. Lutein and β-carotene were the main carotenoids extracted with ethanol while lipids come out with hexane.

Keywords: biodiesel, Chlorella vulgaris, extraction, lutein

Procedia PDF Downloads 321
19404 Biodiversity Conservation: A Path to a Healthy Afghanistan

Authors: Nadir Sidiqi

Abstract:

Biodiversity conservation is humanity’s building block to sustain lives - ultimately allowing all living and nonliving creatures to interact in a balanced proportion. Humanity’s challenge in the 21st century is to maintain biodiversity without harming the natural habitat of plants, animals and beneficial microorganisms. There are many good reasons to consider why biodiversity is important to every nation around the world, especially for a nation like Afghanistan. One of the major values of biodiversity is its economic value: biodiversity provides goods and services to the Afghan nation directly through links and components such as the maintenance of traditional crops, medicine, fruits, animals, grazing, fuel, timber, harvesting, fishing, hunting and related supplies. Biodiversity is the variety of the living components, such as humans, plants, animals, and microorganisms, and nonliving components interaction, including air, water, sunlight, soil, humidity and environmental factors in an area. There are many ways of gauging the value of biodiversity. As an ecosystem, biodiversity includes such benefits as soil fertility, erosion control, crop pollination, crop rotation, and pest control. The conservation of biodiversity is crucial for these benefits, which would be impossible to replace. Biodiversity conservation also has heritage values; this wealth of genetic diversity provides backup to rural people living close together.

Keywords: Afghanistan, biodiversity, conservation, economy, environment

Procedia PDF Downloads 506
19403 A Nanoelectromechanical Tunable Oscillator Base on a High-Q Optical Cavity

Authors: Jianguo Huang, Hong Cai, Bin Dong, Jifang Tao, Aiqun Liu, Dim-Lee Kwong, Yuandong Gu

Abstract:

We developed a miniaturized tunable optomechanical oscillator based on the nanoelectromechanical systems (NEMS) technology, and its frequencies can be electrostatically tuned by as much as 10%. By taking both advantages of optical and electrical spring, the oscillator achieves a high tuning sensitivity without resorting to mechanical tension. In particular, the proposed high-Q optical cavity design greatly enhances the system sensitivity, making it extremely sensitive to the small motional signal.

Keywords: nanoelectromechanical systems (NEMS), nanotechnology, optical force, oscillator

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19402 The Cost-Effectiveness of High-Volume Hospital’s Surgical Care for Pancreatic Cancer: Economic Evidence Reviewed

Authors: Shannon Hearney, Jeffrey Hoch

Abstract:

Pancreatic cancer is a notoriously costly and deadly form of cancer. Many types of treatment centers exist for patients to seek care from, including high-volume centers which have shown promise to provide the highest quality of care. While it may be true that this type of center provides the best care it is unclear if that care is cost-effective. Studies in the US have confirmed that high-volume hospitals do provide higher quality of care but have shown inconsistencies in the cost-effectiveness of that care. Other studies, like those from Finland have shown that high-volume centers had lower mortality and lower costs than low-volume centers. This paper thus seeks to review the current scientific literature to better understand if high-volume centers are cost-effective in delivering care in both a European setting and in the US. A review of major reference databases such as Medline, Embase and PubMed will be conducted for cost-effectiveness studies on the surgical treatment of pancreatic cancer at high-volume centers. Possible MeSH terms to be included, but not limited to, are: “pancreatic cancer”, “cost analysis”, “cost-effectiveness”, “economic evaluation”, “pancreatic neoplasms”, “surgical”, and “high-volume”. Studies must also have been available in the English language. This review will encompass European scientific literature, as well as those in the US. Based on our preliminary findings, we anticipate high-volume hospitals to provide better care at greater costs. We anticipate that high-volume hospitals may be cost-effective in different contexts depending on the national structure of a healthcare system. Countries with more centralized and socialized healthcare may yield results that are more cost-effective. High-volume centers may differ in their cost-effectiveness of the surgical care of pancreatic cancer internationally especially when comparing those in the United States to others throughout Europe.

Keywords: cost-effectiveness analysis, economic evaluation, pancreatic cancer, scientific literature review

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19401 Common Caper (Capparis Spinosa L.) From Oblivion and Neglect to the Interface of Medicinal Plants

Authors: Ahmad Alsheikh Kaddour

Abstract:

Herbal medicine has been a long-standing phenomenon in Arab countries since ancient times because of its breadth and moderate temperament. Therefore, it possesses a vast natural and economic wealth of medicinal and aromatic herbs. This prompted ancient Egyptians and Arabs to discover and exploit them. The economic importance of the plant is not only from medicinal uses; it is a plant of high economic value for its various uses, especially in food, cosmetic and aromatic industries. It is also an ornamental plant and soil stabilization. The main objective of this research is to study the chemical changes that occur in the plant during the growth period, as well as the production of plant buds, which were previously considered unwanted plants. The research was carried out in the period 2021-2022 in the valley of Al-Shaflah (common caper), located in Qumhana village, 7 km north of Hama Governorate, Syria. The results of the research showed a change in the percentage of chemical components in the plant parts. The ratio of protein content and the percentage of fatty substances in fruits and the ratio of oil in the seeds until the period of harvesting of these plant parts improved, but the percentage of essential oils decreased with the progress of the plant growth, while the Glycosides content where improved with the plant aging. The production of buds is small, with dimensions as 0.5×0.5 cm, which is preferred for commercial markets, harvested every 2-3 days in quantities ranging from 0.4 to 0.5 kg in one cut/shrubs with 3 years’ age as average for the years 2021-2022. The monthly production of a shrub is between 4-5 kg per month. The productive period is 4 months approximately. This means that the seasonal production of one plant is 16-20 kg and the production of 16-20 tons per year with a plant density of 1,000 shrubs per hectare, which is the optimum rate of cultivation in the unit of mass, given the price of a kg of these buds is equivalent to 1 US $; however, this means that the annual output value of the locally produced hectare ranges from 16,000 US $ to 20,000 US $ for farmers. The results showed that it is possible to transform the cultivation of this plant from traditional random to typical areas cultivation, with a plant density of 1,000-1,100 plants per hectare according to the type of soil to obtain production of medicinal and nutritious buds, as well as, the need to pay attention to this national wealth and invest in the optimal manner, which leads to the acquisition of hard currency through export to support the national income.

Keywords: common caper, medicinal plants, propagation, medical, economic importance

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19400 Comparison of Catalyst Support for High Pressure Reductive Amination

Authors: Tz-Bang Du, Cheng-Han Hsieh, Li-Ping Ju, Hung-Jie Liou

Abstract:

Polyether amines synthesize by secondary hydroxyl polyether diol play an important role in epoxy hardener. The low molecular weight product is used in low viscosity and high transparent polyamine product for the logo, ground cover, especially for wind turbine blade, while the high molecular weight products are used in advanced agricultures such as a high-speed railway. High-pressure reductive amination process is required for producing these amines. In the condition of higher than 150 atm pressure and 200 degrees Celsius temperature, supercritical ammonia is used as a reactant and also a solvent. It would be a great challenge to select a catalyst support for such high-temperature alkaline circumstance. In this study, we have established a six-autoclave-type (SAT) high-pressure reactor for amination catalyst screening, which six experiment conditions with different temperature and pressure could be examined at the same time. We synthesized copper-nickel catalyst on different shaped alumina catalyst support and evaluated the catalyst activity for high-pressure reductive amination of polypropylene glycol (PPG) by SAT reactor. Ball type gamma alumina, ball type activated alumina and pellet type gamma alumina catalyst supports are evaluated in this study. Gamma alumina supports have shown better activity on PPG reductive amination than activated alumina support. In addition, the catalysts are evaluated in fixed bed reactor. The diamine product was successfully synthesized via this catalyst and the strength of the catalysts is measured. The crush strength of blank supports is about 13.5 lb for both gamma alumina and activated alumina. The strength increases to 20.3 lb after synthesized to be copper-nickel catalyst. After test in the fixed bed high-pressure reductive amination process for 100 hours, the crush strength of the used catalyst is 3.7 lb for activated alumina support, 12.0 lb for gamma alumina support. The gamma alumina is better than activated alumina to use as catalyst support in high-pressure reductive amination process.

Keywords: high pressure reductive amination, copper nickel catalyst, polyether amine, alumina

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19399 Auto-Tuning of CNC Parameters According to the Machining Mode Selection

Authors: Jenq-Shyong Chen, Ben-Fong Yu

Abstract:

CNC(computer numerical control) machining centers have been widely used for machining different metal components for various industries. For a specific CNC machine, its everyday job is assigned to cut different products with quite different attributes such as material type, workpiece weight, geometry, tooling, and cutting conditions. Theoretically, the dynamic characteristics of the CNC machine should be properly tuned match each machining job in order to get the optimal machining performance. However, most of the CNC machines are set with only a standard set of CNC parameters. In this study, we have developed an auto-tuning system which can automatically change the CNC parameters and in hence change the machine dynamic characteristics according to the selection of machining modes which are set by the mixed combination of three machine performance indexes: the HO (high surface quality) index, HP (high precision) index and HS (high speed) index. The acceleration, jerk, corner error tolerance, oscillation and dynamic bandwidth of machine’s feed axes have been changed according to the selection of the machine performance indexes. The proposed auto-tuning system of the CNC parameters has been implemented on a PC-based CNC controller and a three-axis machining center. The measured experimental result have shown the promising of our proposed auto-tuning system.

Keywords: auto-tuning, CNC parameters, machining mode, high speed, high accuracy, high surface quality

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19398 Measure of Pleasure of Drug Users

Authors: Vano Tsertsvadze, Marina Chavchanidze, Lali Khurtsia

Abstract:

Problem of drug use is often seen as a combination of psychological and social problems, but this problem can be considered as economically rational decision in the process of buying pleasure (looking after children, reading, harvesting fruits in the fall, sex, eating, etc.). Before the adoption of the decisions people face to a trade-off - when someone chooses a delicious meal, she takes a completely rational decision, that the pleasure of eating has a lot more value than the pleasure which she will experience after two months diet on the summer beach showing off her beautiful body. This argument is also true for alcohol, drugs and cigarettes. Smoking has a negative effect on health, but smokers are not afraid of the threat of a lung cancer after 40 years, more valuable moment is a pleasure from smoking. Our hypothesis - unsatisfied pleasure and frustration, probably determines the risk of dependence on drug abuse. The purpose of research: 1- to determine the relative measure unit of pleasure, which will be used to measure and assess the intensity of various human pleasures. 2- to compare the intensity of the pleasure from different kinds of activity, with pleasures received from drug use. 3- Based on the analysis of data, to identify factors affecting the rational decision making. Research method: Respondents will be asked to recall the greatest pleasure of their life, which will be used as a measure of the other pleasures. The study will use focus groups and structured interviews.

Keywords: drug, drug-user, measurement, satisfaction

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19397 Designing, Processing and Isothermal Transformation of Al-Si High Carbon Ultrafine High Strength Bainitic Steel

Authors: Mohamed K. El-Fawkhry, Ahmed Shash, Ahmed Ismail Zaki Farahat, Sherif Ali Abd El Rahman, Taha Mattar

Abstract:

High-carbon, silicon-rich steels are commonly suggested to obtain very fine bainitic microstructure at low temperature ranged from 200 to 300°C. Thereby, the resulted microstructure consists of slender of bainitic-ferritic plates interwoven with retained austenite. The advanced strength and ductility package of this steel is much dependent on the fineness of bainitic ferrite, as well as the retained austenite phase. In this article, Aluminum to Silicon ratio, and the isothermal transformation temperature have been adopted to obtain ultra high strength high carbon steel. Optical and SEM investigation of the produced steels have been performed. XRD has been used to track the retained austenite development as a result of the change in the chemical composition of developed steels and heat treatment process. Mechanical properties in terms of hardness and microhardness of obtained phases and structure were investigated. It was observed that the increment of aluminum to silicon ratio has a great effect in promoting the bainitic transformation, in tandem with improving the stability and the fineness of retained austenite. Such advanced structure leads to enhancement in the whole mechanical properties of the high carbon steel.

Keywords: high-carbon steel, silicon-rich steels, fine bainitic microstructure, retained austenite, isothermal transformation

Procedia PDF Downloads 335
19396 Simulation-Based Optimization of a Non-Uniform Piezoelectric Energy Harvester with Stack Boundary

Authors: Alireza Keshmiri, Shahriar Bagheri, Nan Wu

Abstract:

This research presents an analytical model for the development of an energy harvester with piezoelectric rings stacked at the boundary of the structure based on the Adomian decomposition method. The model is applied to geometrically non-uniform beams to derive the steady-state dynamic response of the structure subjected to base motion excitation and efficiently harvest the subsequent vibrational energy. The in-plane polarization of the piezoelectric rings is employed to enhance the electrical power output. A parametric study for the proposed energy harvester with various design parameters is done to prepare the dataset required for optimization. Finally, simulation-based optimization technique helps to find the optimum structural design with maximum efficiency. To solve the optimization problem, an artificial neural network is first trained to replace the simulation model, and then, a genetic algorithm is employed to find the optimized design variables. Higher geometrical non-uniformity and length of the beam lowers the structure natural frequency and generates a larger power output.

Keywords: piezoelectricity, energy harvesting, simulation-based optimization, artificial neural network, genetic algorithm

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19395 Information and Communication Technology Learning between Parents and High School Students

Authors: Yu-Mei Tseng, Chih-Chun Wu

Abstract:

As information and communication technology (ICT) has become a part of people’s lives, most teenagers born after the 1980s and grew up in internet generation are called digital natives. Meanwhile, those teenagers’ parents are called digital immigrants. They need to keep learning new skills of ICT. This study investigated that high school students helped their parents set up social network services (SNS) and taught them how to use ICT. This study applied paper and pencil anonymous questionnaires that asked the ICT learning and ICT products using in high school students’ parents. The sample size was 2,621 high school students, including 1,360 (51.9%) males and 1,261 (48.1%) females. The sample was from 12 high school and vocational high school in central Taiwan. Results from paired sample t-tests demonstrated regardless genders, both male and female high school students help mothers set up Facebook and LINE more often than fathers. In addition, both male and female high school students taught mothers to use ICT more often than fathers. Meanwhile, both male and female high school students teach mothers to use SNS more often than fathers. The results showed that intergenerational ICT teaching occurred more often between mothers and her children than fathers. It could imply that mothers play a more important role in family ICT learning than fathers, or it could be that mothers need more help regarding ICT than fathers. As for gender differences, results from the independent t-tests showed that female high school students were more likely than male ones to help their parents setup Facebook and LINE. In addition, compared to male high school students, female ones were more likely to teach their parents to use smartphone, Facebook and LINE. However, no gender differences were detected in teaching mothers. The gender differences results suggested that female teenagers offer more helps to their parents regarding ICT learning than their male counterparts. As for area differences, results from the independent t-tests showed that the high school in remote area students were more likely than metropolitan ones to teach parents to use computer, search engine and download files of audio and video. The area differences results might indicate that remote area students were more likely to teach their parents how to use ICT. The results from this study encourage children to help and teach their parents with ICT products.

Keywords: adult ICT learning, family ICT learning, ICT learning, urban-rural gap

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19394 Dominant Correlation Effects in Atomic Spectra

Authors: Hubert Klar

Abstract:

High double excitation of two-electron atoms has been investigated using hyperpherical coordinates within a modified adiabatic expansion technique. This modification creates a novel fictitious force leading to a spontaneous exchange symmetry breaking at high double excitation. The Pauli principle must therefore be regarded as approximation valid only at low excitation energy. Threshold electron scattering from high Rydberg states shows an unexpected time reversal symmetry breaking. At threshold for double escape we discover a broad (few eV) Cooper pair.

Keywords: correlation, resonances, threshold ionization, Cooper pair

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19393 Preharvest and Postharvest Factors Influencing Resveratrol, Myricetin and Quercetin Content of Wine

Authors: Mariam Khomasuridze, Nino Chkhartishvili, Irma Chanturia

Abstract:

The influence of preharvest and postharvest factors on resveratrol, myricetin and quercetin content of wine was studied during the experiment. The content of cis and trans resveratrol, myricetin and quercetin were analyzed by HPLC. In frame of experiment, the various factors affecting on wine composition were researched: variety, climate, viticulture practices, grape maturity, harvesting methods and wine making techniques. The results have shown that varietal potential and amount of yield play the most important role in formation of antioxidant compounds. Based on achieved results, the usage of medium roast oak chips protects resveratrol, myricetin, and quercetin from coagulation and precipitation. Compared to the control samples, the wines, produced by addition of oak chips were approximately four times richer with these antioxidant compounds. The retention of resveratrol was lowered with 45 % in wines, producing in Qvevri by Georgian traditional technology without controlling temperature during fermentation. The opposite effects in case of myricetin, quercetin and total phenolics content were determined. Their concentrations were higher with 56-78%, then in the fermented tank at 22 -25 °C. As the result of the experiment, the optimal technology scheme of wine was worked out, reached by biologically active compounds: resveratrol, myricetin, and quercetin.

Keywords: resveratrol, miricetin, quercetin, wine

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19392 Numerical and Experimental Investigation of a Mechanical System with a Pendulum

Authors: Andrzej Mitura, Krzysztof Kecik, Michal Augustyniak

Abstract:

This paper presents a numerical and experimental research of a nonlinear two degrees of freedom system. The tested system consists of a mechanical oscillator (the primary subsystem) with the attached pendulum (the secondary subsystem). The oscillator is suspended on a linear (or nonlinear) coil spring and a nonlinear magnetorheorogical damper and it is excited kinematically. Added pendulum can be used to reduce vibration of a primary subsystem or to energy harvesting. The numerical and experimental investigations showed that the pendulum can perform several types of motion, for example: chaotic motion, constant position in lower or upper (stable inverted pendulum), rotation, symmetrical or asymmetrical swinging vibrations. The main objective of this study is to determine an influence of system parameters for increasing the zone when the pendulum rotates. As a final effect a semi-active control method to change the pendulum solution on the rotation is proposed. To the implementation of this method the magnetorheorogical damper is applied. Continuous rotation of the pendulum is desirable for recovery of energy. The work is financed by Grant no. 0234/IP2/2011/71 from the Polish Ministry of Science and Higher Education in years 2012-2014.

Keywords: autoparametric vibrations, chaos and rotation control, magnetorheological damper

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19391 A Novel Eccentric Lapping Method with Two Rotatable Lapping Plates for Finishing Cemented Carbide Balls

Authors: C. C. Lv, Y. L. Sun, D. W. Zuo

Abstract:

Cemented carbide balls are usually implemented in industry under the environment of high speed, high temperature, corrosiveness and strong collisions. However, its application is limited due to high fabrication cost, processing efficiency and quality. A novel eccentric lapping method with two rotatable lapping plates was proposed in this paper. A mathematical model was constructed to analyze the influence of each design parameter on this lapping method. To validate this new lapping method, an orthogonal experiment was conducted with cemented carbide balls (YG6). The simulation model was verified and the optimal lapping parameters were derived. The results show that the surface roundness of the balls reaches to 0.65um from 2um in 1 hour using this lapping method. So, using this novel lapping method, it can effectively improve the machining precision and efficiency of cemented carbide balls.

Keywords: cemented carbide balls, eccentric lapping, high precision, lapping tracks, V-groove

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19390 Production of Amorphous Boron Powder via Chemical Vapor Deposition (CVD)

Authors: Meltem Bolluk, Ismail Duman

Abstract:

Boron exhibits the properties of high melting temperature (2273K to 2573 K), high hardness (Mohs: 9,5), low density (2,340 g/cm3), high chemical resistance, high strength, and semiconductivity (band gap:1,6-2,1 eV). These superior properties enable to use it in several high-tech areas from electronics to nuclear industry and especially in high temperature metallurgy. Amorphous boron and crystalline boron have different application areas. Amorphous boron powder (directly amorphous and/or α-rhombohedral) is preferred in rocket firing, airbag inflating and in fabrication of superconducting MgB2 wires. The conventional ways to produce elemental boron with a purity of 85 pct to 95 prc are metallothermic reduction, fused salt electrolysis and mechanochemical synthesis; but the only way to produce high-purity boron powders is Chemical Vapour Deposition (Hot Surface CVD). In this study; amorphous boron powders with a minimum purity of 99,9 prc were synthesized in quartz tubes using BCl3-H2 gas mixture by CVD. Process conditions based on temperature and gas flow rate were determined. Thermodynamical interpretation of BCl3-H2 system for different temperatures and molar rates were performed using Fact Sage software. The characterization of powders was examined by using Xray diffraction (XRD), Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM), Stereo Microscope (SM), Helium gas pycnometer analysis. The purities of final products were determined by titration after lime fusion.

Keywords: amorphous boron, CVD, powder production, powder characterization

Procedia PDF Downloads 196