Search results for: liquid mass transfer coefficient
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9072

Search results for: liquid mass transfer coefficient

2052 Development of Nondestructive Imaging Analysis Method Using Muonic X-Ray with a Double-Sided Silicon Strip Detector

Authors: I-Huan Chiu, Kazuhiko Ninomiya, Shin’ichiro Takeda, Meito Kajino, Miho Katsuragawa, Shunsaku Nagasawa, Atsushi Shinohara, Tadayuki Takahashi, Ryota Tomaru, Shin Watanabe, Goro Yabu

Abstract:

In recent years, a nondestructive elemental analysis method based on muonic X-ray measurements has been developed and applied for various samples. Muonic X-rays are emitted after the formation of a muonic atom, which occurs when a negatively charged muon is captured in a muon atomic orbit around the nucleus. Because muonic X-rays have higher energy than electronic X-rays due to the muon mass, they can be measured without being absorbed by a material. Thus, estimating the two-dimensional (2D) elemental distribution of a sample became possible using an X-ray imaging detector. In this work, we report a non-destructive imaging experiment using muonic X-rays at Japan Proton Accelerator Research Complex. The irradiated target consisted of polypropylene material, and a double-sided silicon strip detector, which was developed as an imaging detector for astronomical observation, was employed. A peak corresponding to muonic X-rays from the carbon atoms in the target was clearly observed in the energy spectrum at an energy of 14 keV, and 2D visualizations were successfully reconstructed to reveal the projection image from the target. This result demonstrates the potential of the non-destructive elemental imaging method that is based on muonic X-ray measurement. To obtain a higher position resolution for imaging a smaller target, a new detector system will be developed to improve the statistical analysis in further research.

Keywords: DSSD, muon, muonic X-ray, imaging, non-destructive analysis

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2051 Numerical Modelling of Hydrodynamic Drag and Supercavitation Parameters for Supercavitating Torpedoes

Authors: Sezer Kefeli, Sertaç Arslan

Abstract:

In this paper, supercavitationphenomena, and parameters are explained, and hydrodynamic design approaches are investigated for supercavitating torpedoes. In addition, drag force calculation methods ofsupercavitatingvehicles are obtained. Basically, conventional heavyweight torpedoes reach up to ~50 knots by classic hydrodynamic techniques, on the other hand super cavitating torpedoes may reach up to ~200 knots, theoretically. However, in order to reachhigh speeds, hydrodynamic viscous forces have to be reduced or eliminated completely. This necessity is revived the supercavitation phenomena that is implemented to conventional torpedoes. Supercavitation is a type of cavitation, after all, it is more stable and continuous than other cavitation types. The general principle of supercavitation is to separate the underwater vehicle from water phase by surrounding the vehicle with cavitation bubbles. This situation allows the torpedo to operate at high speeds through the water being fully developed cavitation. Conventional torpedoes are entitled as supercavitating torpedoes when the torpedo moves in a cavity envelope due to cavitator in the nose section and solid fuel rocket engine in the rear section. There are two types of supercavitation phase, these are natural and artificial cavitation phases. In this study, natural cavitation is investigated on the disk cavitators based on numerical methods. Once the supercavitation characteristics and drag reduction of natural cavitationare studied on CFD platform, results are verified with the empirical equations. As supercavitation parameters cavitation number (), pressure distribution along axial axes, drag coefficient (C_?) and drag force (D), cavity wall velocity (U_?) and dimensionless cavity shape parameters, which are cavity length (L_?/d_?), cavity diameter(d_ₘ/d_?) and cavity fineness ratio (〖L_?/d〗_ₘ) are investigated and compared with empirical results. This paper has the characteristics of feasibility study to carry out numerical solutions of the supercavitation phenomena comparing with empirical equations.

Keywords: CFD, cavity envelope, high speed underwater vehicles, supercavitating flows, supercavitation, drag reduction, supercavitation parameters

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2050 Photocatalytic Hydrogen Production, Effect of Metal Particle Size and Their Electronic/Optical Properties on the Reaction

Authors: Hicham Idriss

Abstract:

Hydrogen production from water is one of the most promising methods to secure renewable sources or vectors of energy for societies in general and for chemical industries in particular. At present over 90% of the total amount of hydrogen produced in the world is made from non-renewable fossil fuels (via methane reforming). There are many methods for producing hydrogen from water and these include reducible oxide materials (solar thermal production), combined PV/electrolysis, artificial photosynthesis and photocatalysis. The most promising of these processes is the one relying on photocatalysis; yet serious challenges are hindering its success so far. In order to make this process viable considerable improvement of the photon conversion is needed. Among the key studies that our group has been conducting in the last few years are those focusing on synergism between the semiconductor phases, photonic band gap materials, pn junctions, plasmonic resonance responses, charge transfer to metal cations, in addition to metal dispersion and band gap engineering. In this work results related to phase transformation of the anatase to rutile in the case of TiO2 (synergism), of Au and Ag dispersion (electron trapping and hydrogen-hydrogen recombination centers) as well as their plasmon resonance response (visible light conversion) are presented and discussed. It is found for example that synergism between the two common phases of TiO2 (anatase and rutile) is sensitive to the initial particle size. It is also found, in agreement with previous results, that the rate is very sensitive to the amount of metals (with similar particle size) on the surface unlike the case of thermal heterogeneous catalysis.

Keywords: photo-catalysis, hydrogen production, water splitting, plasmonic

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2049 Evaluation and Selection of Elite Jatropha Genotypes for Biofuel

Authors: Bambang Heliyanto, Rully Dyah Purwati, Hasnam, Fadjry Djufry

Abstract:

Jatropha curcas L., a drought tolerant and monoecious perennial shrub, has received attention worldwide during the past decade. Realizing the facts, the Indonesian government has decided to option for Jatropha and palm oil for in country biofuel production. To support the program development of high yielding jatropha varieties is necessary. This paper reviews Jatropha improvement program in Indonesia using mass selection and hybrid development. To start with, at the end of 2005, in-country germplasm collection was mobilized to Lampung and Nusa Tenggara Barat (NTB) provinces and successfully collected 15 provenances/sub-provenances which serves as a base population for selection. A significant improvement has been achieved through a simple recurrent breeding selection during 2006 to 2007. Seed yield productivity increased more than double, from 0.36 to 0.97 ton dry seed per hectare during the first selection cycle (IP-1), and then increased to 2.2 ton per hectare during the second cycles (IP-2) in Lampung provenance. Similar result was also observed in NTB provenance. Seed yield productivity increased from 0.43 ton to 1 ton dry seed per hectare in the first cycle (IP-1), and then 1.9 ton in the second cycle (IP-2). In 2008, the population IP-3 resulted from the third cycle of selection have been identified which were capable of producing 2.2 to 2.4 ton seed yield per hectare. To improve the seed yield per hectare, jatropha hybrid varieties was developed involving superior provenances. As a result a Jatropha Energy Terbarukan (JET) variety-2 was released in 2017 with seed yield potential of 2.6 ton per hectare. The use of this high yielding genotypes for biofuel is discussed.

Keywords: Jatropha curcas, provenance, biofuel, improve population, hybrid

Procedia PDF Downloads 161
2048 Role of Biomaterial Surface Nanotopography on Protein Unfolding and Immune Response

Authors: Rahul Madathiparambil Visalakshan, Alex Cavallaro, John Hayball, Krasimir Vasilev

Abstract:

The role of biomaterial surface nanotopograhy on fibrinogen adsorption and unfolding, and the subsequent immune response were studied. Inconsistent topography and varying chemical functionalities along with a lack of reproducibility pose a challenge in determining the specific effects of nanotopography or chemistry on proteins and cells. It is important to have a well-defined nanotopography with a homogeneous chemistry to study the real effect of nanotopography on biological systems. Therefore, we developed a technique that can produce well-defined and highly reproducible topography to identify the role of specific roughness, size, height and density with the presence of homogeneous chemical functionality. Using plasma polymerisation of oxazoline monomers and immobilized gold nanoparticles we created surfaces with an equal number density of nanoparticles of different sizes. This surface was used to study the role of surface nanotopography and the interplay of surface chemistry on proteins and immune cells. The effect of nanotopography on fibrinogen adsorption was investigated using Quartz Cristal Microbalance with Dissipation and micro BCA. The mass of fibrinogen adsorbed on the surface increased with increasing size of nano-topography. Protein structural changes up on adsorption to the nano rough surface was studied using circular dichroism spectroscopy. Fibrinogen unfolding varied depending on the specific nanotopography of the surfaces. It was revealed that the in vitro immune response to the nanotopography surfaces changed due to this protein unfolding.

Keywords: biomaterial inflammation, protein and cell responses, protein unfolding, surface nanotopography

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2047 Climate Changes Impact on Artificial Wetlands

Authors: Carla Idely Palencia-Aguilar

Abstract:

Artificial wetlands play an important role at Guasca Municipality in Colombia, not only because they are used for the agroindustry, but also because more than 45 species were found, some of which are endemic and migratory birds. Remote sensing was used to determine the changes in the area occupied by water of artificial wetlands by means of Aster and Modis images for different time periods. Evapotranspiration was also determined by three methods: Surface Energy Balance System-Su (SEBS) algorithm, Surface Energy Balance- Bastiaanssen (SEBAL) algorithm, and Potential Evapotranspiration- FAO. Empirical equations were also developed to determine the relationship between Normalized Difference Vegetation Index (NDVI) versus net radiation, ambient temperature and rain with an obtained R2 of 0.83. Groundwater level fluctuations on a daily basis were studied as well. Data from a piezometer placed next to the wetland were fitted with rain changes (with two weather stations located at the proximities of the wetlands) by means of multiple regression and time series analysis, the R2 from the calculated and measured values resulted was higher than 0.98. Information from nearby weather stations provided information for ordinary kriging as well as the results for the Digital Elevation Model (DEM) developed by using PCI software. Standard models (exponential, spherical, circular, gaussian, linear) to describe spatial variation were tested. Ordinary Cokriging between height and rain variables were also tested, to determine if the accuracy of the interpolation would increase. The results showed no significant differences giving the fact that the mean result of the spherical function for the rain samples after ordinary kriging was 58.06 and a standard deviation of 18.06. The cokriging using for the variable rain, a spherical function; for height variable, the power function and for the cross variable (rain and height), the spherical function had a mean of 57.58 and a standard deviation of 18.36. Threatens of eutrophication were also studied, given the unconsciousness of neighbours and government deficiency. Water quality was determined over the years; different parameters were studied to determine the chemical characteristics of water. In addition, 600 pesticides were studied by gas and liquid chromatography. Results showed that coliforms, nitrogen, phosphorous and prochloraz were the most significant contaminants.

Keywords: DEM, evapotranspiration, geostatistics, NDVI

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2046 Vitamin D Status in Tunisian Obese Patients

Authors: O. Berriche, R. Ben Othmen, H. Sfar, H. Abdesslam, S. Bou Meftah, S. Bhouri, F. Mahjoub, C. Amrouche, H. Jamoussi

Abstract:

Introduction: Although current evidence emphasizes a high prevalence of vitamin D deficiency and an inverse association between serum 25-hydroxyvitamin D (25-OHD) concentration and obesity, no studies have been conducted in Tunisian obese. The objectives of our study were to estimate the vitamin D deficiency in obese, identify risk factors for vitamin D deficiency, demonstrating a possible association between vitamin D levels and metabolic parameters. Methods: This was a descriptive study of 100 obese 18-65 year-old. Anthropometric measurements were determined. Fasting blood samples were assessed for the following essays : serum calcium, 25 OH vitamin D, inorganic phosphorus, fasting glucose, HDL, LDL cholesterol and triglyceride. Insulin resistance was evaluated by fasting insulin, HOMA-IR and HOMA-ß. Consumption of foods riche in vitamin D, sunscreen use, wearing protective clothes and exposed surface were assessed through applied questionnaires. Results: The deficit of vitamin D (< 30 ng/ml) among obese was 98,8%. Half of them had a rate < 10ng/ml. Environmental factors involved in vitamin D deficiency are : the veil (p = 0,001), wearing protective clothes (p = 0,04) and the exposed surface (p = 0,011) and dietary factors are represented by the daily caloric intake (p = 0,0001). The percent of fat mass was negatively related to vitamin D levels (p = 0,01) but not with BMI (p = 0,11) or waist circumference (p = 0,88). Similarly, lipid and glucose profile had no link with vitamin D. We found no relationship between Insulin resistance and vitamin D levels. Conclusion: At the end of our study, we have identified a very important vitamin D deficiency among obese. Dosage and systematic supplementation should be applied and for that physician awareness is needed.

Keywords: insulinresistance, risk factors, obesity, vitamin D

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2045 Exploratory Factor Analysis of Natural Disaster Preparedness Awareness of Thai Citizens

Authors: Chaiyaset Promsri

Abstract:

Based on the synthesis of related literatures, this research found thirteen related dimensions that involved the development of natural disaster preparedness awareness including hazard knowledge, hazard attitude, training for disaster preparedness, rehearsal and practice for disaster preparedness, cultural development for preparedness, public relations and communication, storytelling, disaster awareness game, simulation, past experience to natural disaster, information sharing with family members, and commitment to the community (time of living).  The 40-item of natural disaster preparedness awareness questionnaire was developed based on these thirteen dimensions. Data were collected from 595 participants in Bangkok metropolitan and vicinity. Cronbach's alpha was used to examine the internal consistency for this instrument. Reliability coefficient was 97, which was highly acceptable.  Exploratory Factor Analysis where principal axis factor analysis was employed. The Kaiser-Meyer-Olkin index of sampling adequacy was .973, indicating that the data represented a homogeneous collection of variables suitable for factor analysis. Bartlett's test of Sphericity was significant for the sample as Chi-Square = 23168.657, df = 780, and p-value < .0001, which indicated that the set of correlations in the correlation matrix was significantly different and acceptable for utilizing EFA. Factor extraction was done to determine the number of factors by using principal component analysis and varimax.  The result revealed that four factors had Eigen value greater than 1 with more than 60% cumulative of variance. Factor #1 had Eigen value of 22.270, and factor loadings ranged from 0.626-0.760. This factor was named as "Knowledge and Attitude of Natural Disaster Preparedness".  Factor #2 had Eigen value of 2.491, and factor loadings ranged from 0.596-0.696. This factor was named as "Training and Development". Factor #3 had Eigen value of 1.821, and factor loadings ranged from 0.643-0.777. This factor was named as "Building Experiences about Disaster Preparedness".  Factor #4 had Eigen value of 1.365, and factor loadings ranged from 0.657-0.760. This was named as "Family and Community". The results of this study provided support for the reliability and construct validity of natural disaster preparedness awareness for utilizing with populations similar to sample employed.

Keywords: natural disaster, disaster preparedness, disaster awareness, Thai citizens

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2044 The Impact of Diabetes Mellitus on Skin and Soft Tissue Infections

Authors: Stephanie Cheng, Benjamin Poh, Vivyan Tay, Sachin Mathur

Abstract:

Aim: Diabetes mellitus (DM) is a worldwide pandemic affecting 500 million people. It is known to be associated with increased susceptibility to soft tissue infections (STI). Despite being a major public health burden, the literature relating the effects of DM and the presentation, severity and healing of STIs in general surgical patients remain limited. Methods: We conducted a retrospective review of all patients admitted with STI in a tertiary teaching hospital over a 12-month period. Patient demographics and surgical outcomes were collected and analyzed. Results: During the study period, 1059 patients were admitted for STIs, of which 936 (88%) required surgical intervention. Diabetic patients were presented with a higher body-mass index (BMI) (28 vs 26), larger abscess size (24 vs 14 cm²) and a longer length of stay (LOS)(4.4 days vs 2.9 days). They also underwent a higher proportion of wide debridement as well as application of negative pressure wound therapy (NPWT) (42% vs 35%). More diabetic patients underwent subsequent re-operation within the same sitting (8 vs 4). There were no differences in re-admission rates within 30 days nor subsequent abscess formation in those followed for 6 months. Conclusion: The incidence of STIs among DM patients represents a significant disease burden; surgeons should consider intensive patient counseling and partnering with primary care providers in order to help reduce the incidence of future STI admissions based on lifestyle modification and glucose control.

Keywords: general surgery, emergency general surgery, acute care surgery, soft tissue infections, diabetes mellitus

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2043 In situ Immobilization of Mercury in a Contaminated Calcareous Soil Using Water Treatment Residual Nanoparticles

Authors: Elsayed A. Elkhatib, Ahmed M. Mahdy, Mohamed L. Moharem, Mohamed O. Mesalem

Abstract:

Mercury (Hg) is one of the most toxic and bio-accumulative heavy metal in the environment. However, cheap and effective in situ remediation technology is lacking. In this study, the effects of water treatment residuals nanoparticles (nWTR) on mobility, fractionation and speciation of mercury in an arid zone soil from Egypt were evaluated. Water treatment residual nanoparticles with high surface area (129 m 2 g-1) were prepared using Fritsch planetary mono mill. Scanning and transmission electron microscopy revealed that the nanoparticles of WTR nanoparticles are spherical in shape, and single particle sizes are in the range of 45 to 96 nm. The x-ray diffraction (XRD) results ascertained that amorphous iron, aluminum (hydr)oxides and silicon oxide dominating all nWTR, with no apparent crystalline iron–Al (hydr)oxides. Addition of nWTR, greatly increased the Hg sorption capacities of studied soils and greatly reduced the cumulative Hg released from the soils. Application of nWTR at 0.10 and 0.30 % rates reduced the released Hg from the soil by 50 and 85 % respectively. The power function and first order kinetics models well described the desorption process from soils and nWTR amended soils as evidenced by high coefficient of determination (R2) and low SE values. Application of nWTR greatly increased the association of Hg with the residual fraction. Meanwhile, application of nWTR at a rate of 0.3% greatly increased the association of Hg with the residual fraction (>93%) and significantly increased the most stable Hg species (Hg(OH)2 amor) which in turn enhanced Hg immobilization in the studied soils. Fourier transmission infrared spectroscopy analysis indicated the involvement of nWTR in the retention of Hg (II) through OH groups which suggest inner-sphere adsorption of Hg ions to surface functional groups on nWTR. These results demonstrated the feasibility of using a low-cost nWTR as best management practice to immobilize excess Hg in contaminated soils.

Keywords: release kinetics, Fourier transmission infrared spectroscopy, Hg fractionation, Hg species

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2042 The Association between Psychosocial Characteristics, Training Variables and Well-Being: An Exploratory Study among Organizational Workers

Authors: Norshaffika I. Zaiedy Nor, Andrew P. Smith

Abstract:

Background: Training is essential to develop individuals’ expertise to meet current and future job demands and to improve work performance. At the same time, individuals’ well-being is crucial to ensure that they can fully and positively carry out their daily duties. In addition to the studies that have examined what constitutes well-being and the factors behind it, many researchers have investigated the predictors of training effectiveness and transfer of training. However, there has been very little integration between them. This study was an attempt to bridge the gap between training effectiveness predictors and well-being. Purpose: This research paper aimed to investigate the association between well-being among employees and psychosocial characteristics, together with training variables. Training variables consist of motivation to learn; learning; implementation intention; and cognitive dissonance. Methodology: In total, 210 workers who had undergone various training programs completed an online survey measuring various psychosocial characteristics, four training variables, and level of well-being. Findings: The results showed that certain types of positive psychosocial characteristics (e.g., positive personality, positive work behaviors, positive work and resources) predict motivation to learn, learning and implementation intention. Meanwhile, negative psychosocial characteristics (e.g. negative work demands and resources, negative coping) predict cognitive dissonance. Also, all the training variables had a moderate to high correlation with well-being. However, after controlling other variables (age, gender, education and psychosocial characteristics), none of the training variables predicted well-being. Self-determination theory, cognitive dissonance theory, and the DRIVE model were used to explain these findings. Conclusion: As there is limited research on the integration of training variables with well-being, this study gives a new perspective in the field of both training and well-being. Further investigations are needed to examine the relationships between them.

Keywords: cognitive dissonance, implementation intention, learning, motivation to learn, psychosocial characteristics, well-being

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2041 Assessing the Impacts of Riparian Land Use on Gully Development and Sediment Load: A Case Study of Nzhelele River Valley, Limpopo Province, South Africa

Authors: B. Mavhuru, N. S. Nethengwe

Abstract:

Human activities on land degradation have triggered several environmental problems especially in rural areas that are underdeveloped. The main aim of this study is to analyze the contribution of different land uses to gully development and sediment load on the Nzhelele River Valley in the Limpopo Province. Data was collected using different methods such as observation, field data techniques and experiments. Satellite digital images, topographic maps, aerial photographs and the sediment load static model also assisted in determining how land use affects gully development and sediment load. For data analysis, the researcher used the following methods: Analysis of Variance (ANOVA), descriptive statistics, Pearson correlation coefficient and statistical correlation methods. The results of the research illustrate that high land use activities create negative changes especially in areas that are highly fragile and vulnerable. Distinct impact on land use change was observed within settlement area (9.6 %) within a period of 5 years. High correlation between soil organic matter and soil moisture (R=0.96) was observed. Furthermore, a significant variation (p ≤ 0.6) between the soil organic matter and soil moisture was also observed. A very significant variation (p ≤ 0.003) was observed in bulk density and extreme significant variations (p ≤ 0.0001) were observed in organic matter and soil particle size. The sand mining and agricultural activities has contributed significantly to the amount of sediment load in the Nzhelele River. A high significant amount of total suspended sediment (55.3 %) and bed load (53.8 %) was observed within the agricultural area. The connection which associates the development of gullies to various land use activities determines the amount of sediment load. These results are consistent with other previous research and suggest that land use activities are likely to exacerbate the development of gullies and sediment load in the Nzhelele River Valley.

Keywords: drainage basin, geomorphological processes, gully development, land degradation, riparian land use and sediment load

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2040 Application of Data Driven Based Models as Early Warning Tools of High Stream Flow Events and Floods

Authors: Mohammed Seyam, Faridah Othman, Ahmed El-Shafie

Abstract:

The early warning of high stream flow events (HSF) and floods is an important aspect in the management of surface water and rivers systems. This process can be performed using either process-based models or data driven-based models such as artificial intelligence (AI) techniques. The main goal of this study is to develop efficient AI-based model for predicting the real-time hourly stream flow (Q) and apply it as early warning tool of HSF and floods in the downstream area of the Selangor River basin, taken here as a paradigm of humid tropical rivers in Southeast Asia. The performance of AI-based models has been improved through the integration of the lag time (Lt) estimation in the modelling process. A total of 8753 patterns of Q, water level, and rainfall hourly records representing one-year period (2011) were utilized in the modelling process. Six hydrological scenarios have been arranged through hypothetical cases of input variables to investigate how the changes in RF intensity in upstream stations can lead formation of floods. The initial SF was changed for each scenario in order to include wide range of hydrological situations in this study. The performance evaluation of the developed AI-based model shows that high correlation coefficient (R) between the observed and predicted Q is achieved. The AI-based model has been successfully employed in early warning throughout the advance detection of the hydrological conditions that could lead to formations of floods and HSF, where represented by three levels of severity (i.e., alert, warning, and danger). Based on the results of the scenarios, reaching the danger level in the downstream area required high RF intensity in at least two upstream areas. According to results of applications, it can be concluded that AI-based models are beneficial tools to the local authorities for flood control and awareness.

Keywords: floods, stream flow, hydrological modelling, hydrology, artificial intelligence

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2039 Drastic Increase of Wave Dissipation within Metastructures Having Negative Stiffness Inclusions

Authors: D. Chronopoulos, I. Antoniadis, V. Spitas, D. Koulocheris, V. Polenta

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A concept of a simple linear oscillator, incorporating a negative stiffness element is demonstrated to exhibit extraordinary damping properties. This oscillator shares the same overall (static) stiffness, the same mass and the same damping element with a reference classical linear SDOF oscillator. However, it differs from the original SDOF oscillator by appropriately redistributing the component spring stiffness elements and by re-allocating the damping element. Despite the fact that the proposed oscillator incorporates a negative stiffness element, it is designed to be both statically and dynamically stable. Once such an oscillator is optimally designed, it is shown to exhibit an extraordinary apparent damping ratio, which is even several orders of magnitude higher than that of the original SDOF system, especially in cases where the original damping of the SDOF system is low. This damping behavior is not a result of a novel additional extraordinary energy dissipation mechanism, but a result of the phase difference between the positive and the negative stiffness elastic forces, which is in turn a consequence of the proper re-distribution of the stiffness and the damper elements. This fact ensures that an adequate level of elastic forces exists throughout the entire frequency range, able to counteract the inertial and the excitation forces. Next, Acoustic or Phononic Meta-materials are considered, in which one atom is replaced by the concept of the above simple linear oscillator. The results indicate that not only the damping of the meta-material verifies and exceeds the one expected from the so-called "meta-damping" behavior, but also that the band gap of the meta-material can be significantly increased.

Keywords: wave propagation, periodic structures, wave damping, mechanical engineering

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2038 On Board Measurement of Real Exhaust Emission of Light-Duty Vehicles in Algeria

Authors: R. Kerbachi, S. Chikhi, M. Boughedaoui

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The study presents an analysis of the Algerian vehicle fleet and resultant emissions. The emission measurement of air pollutants emitted by road transportation (CO, THC, NOX and CO2) was conducted on 17 light duty vehicles in real traffic. This sample is representative of the Algerian light vehicles in terms of fuel quality (gasoline, diesel and liquefied petroleum gas) and the technology quality (injection system and emission control). The experimental measurement methodology of unit emission of vehicles in real traffic situation is based on the use of the mini-Constant Volume Sampler for gas sampling and a set of gas analyzers for CO2, CO, NOx and THC, with an instrumentation to measure kinematics, gas temperature and pressure. The apparatus is also equipped with data logging instrument and data transfer. The results were compared with the database of the European light vehicles (Artemis). It was shown that the technological injection liquefied petroleum gas (LPG) has significant impact on air pollutants emission. Therefore, with the exception of nitrogen oxide compounds, uncatalyzed LPG vehicles are more effective in reducing emissions unit of air pollutants compared to uncatalyzed gasoline vehicles. LPG performance seems to be lower under real driving conditions than expected on chassis dynamometer. On the other hand, the results show that uncatalyzed gasoline vehicles emit high levels of carbon monoxide, and nitrogen oxides. Overall, and in the absence of standards in Algeria, unit emissions are much higher than Euro 3. The enforcement of pollutant emission standard in developing countries is an important step towards introducing cleaner technology and reducing vehicular emissions.

Keywords: on-board measurements of unit emissions of CO, HC, NOx and CO2, light vehicles, mini-CVS, LPG-fuel, artemis, Algeria

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2037 The Association between Obstructive Sleep Apnea Syndrome and Driver Fatigue in North Taiwan Urban Areas

Authors: Cheng-Yu Tsai, Wen-Te Liu, Chen-Chen Lo, Yin-Tzu Lin, Kang Lo

Abstract:

Background: Driving fatigue related to inadequate or disordered sleep accounts for a major percentage of traffic accidents. Obstructive sleep apnea syndrome (OSAS) is a common respiratory disorder during sleep. However, the effects of OSAS severity on driving drowsiness remain unclear. Objective: The aim of this study is to investigate the relationship between OSAS severity and driving fatigue. Methodologies: The physical condition while driving was obtained from the questionnaires to classify the state of driving fatigue. OSAS severity was quantified as the polysomnography, and the mean hourly number of greater than 3% dips in oxygen saturation during examination in a hospital in New Taipei City (Taiwan). The severity of OSAS was diagnosed by the apnea and hypopnea index (AHI) with the American Academy of Sleep Medicine (AASM) guideline. The logistic regression model was used to examine the associations after adjusted age, gender, neck circumstance, waist circumstance, and body mass index (BMI). Results: There were 880 subjects recruited in this study, who had been done polysomnography for evaluating severity for OSAS as well as completed the driver condition questionnaire. 752 subjects were diagnosed with OSA, and 484 subjects had fatigue driving behavior in the past week. Patients diagnosed with OSAS had a 9.42-fold higher odds ratio (p < 0.01, 95% CI = 5.41 – 16.42) of driving drowsiness for cohorts with a normal degree. Conclusion: We observe the considerable correlation between OSAS and driving fatigue. For the purpose of promoting traffic safety, OSAS should be monitored and treated.

Keywords: obstructive sleep apnea syndrome, driving fatigue, polysomnography, apnea and hypopnea index

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2036 The Effect of Exercise, Reflexology and Chrome on Metabolic Syndrome

Authors: F. Arslan, S.D. Guven, A. Özcan, H. Vatansev, Ö. Taşgin

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Weight, hypertension and dyslipidemia control and increased physical activity are required for the treatment of metabolic syndrome (METS). The purpose of this study was to investigate the effect of core exercise, reflexology and intake chrome picolinate on METS. This study comprised a twelve-week randomized controlled trial. A total of 25 university workers with metabolic risk factors participated in this study voluntarily. They were randomly divided into three groups: Those undertaking a core exercise program (n=7), reflexology intervention group (n=8) and intake chrome group (n=10). The subjects took part in a core exercise program for one hour per day, three days a week and a reflexology interfered for thirty minutes per day, one days a week and chrome group took chrome picolinate every day in week for twelve weeks. The components of metabolic syndrome were analyzed before and after the completion of all the intervention. There were significant differences at pre-prandial blood glucose in the core exercise group and at systolic blood pressure in chrome group after the twelve week interventions (p < 0.005). While High Density Lipoprotein (HDL) excluding the components of METS decreased after the interventions on the all groups; levels of HDL and the other components of METS decreased in reflexology group. There was a clear response to the twelve-week interventions in terms of METS control. Besides, the reflexology intervention should not be applied to individuals with low HDL levels and core exercise and intake chrome picolinate suggested to improve the components of METS.

Keywords: blood pressure, body mass index, exercise, METS, pre-prandial blood glucose

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2035 Investigating the Minimum RVE Size to Simulate Poly (Propylene carbonate) Composites Reinforced with Cellulose Nanocrystals as a Bio-Nanocomposite

Authors: Hamed Nazeri, Pierre Mertiny, Yongsheng Ma, Kajsa Duke

Abstract:

The background of the present study is the use of environment-friendly biopolymer and biocomposite materials. Among the recently introduced biopolymers, poly (propylene carbonate) (PPC) has been gaining attention. This study focuses on the size of representative volume elements (RVE) in order to simulate PPC composites reinforced by cellulose nanocrystals (CNCs) as a bio-nanocomposite. Before manufacturing nanocomposites, numerical modeling should be implemented to explore and predict mechanical properties, which may be accomplished by creating and studying a suitable RVE. In other studies, modeling of composites with rod shaped fillers has been reported assuming that fillers are unidirectionally aligned. But, modeling of non-aligned filler dispersions is considerably more difficult. This study investigates the minimum RVE size to enable subsequent FEA modeling. The matrix and nano-fillers were modeled using the finite element software ABAQUS, assuming randomly dispersed fillers with a filler mass fraction of 1.5%. To simulate filler dispersion, a Monte Carlo technique was employed. The numerical simulation was implemented to find composite elastic moduli. After commencing the simulation with a single filler particle, the number of particles was increased to assess the minimum number of filler particles that satisfies the requirements for an RVE, providing the composite elastic modulus in a reliable fashion.

Keywords: biocomposite, Monte Carlo method, nanocomposite, representative volume element

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2034 New Coating Materials Based on Mixtures of Shellac and Pectin for Pharmaceutical Products

Authors: M. Kumpugdee-Vollrath, M. Tabatabaeifar, M. Helmis

Abstract:

Shellac is a natural polyester resin secreted by insects. Pectins are natural, non-toxic and water-soluble polysaccharides extracted from the peels of citrus fruits or the leftovers of apples. Both polymers are allowed for the use in the pharmaceutical industry and as a food additive. SSB Aquagold® is the aqueous solution of shellac and can be used for a coating process as an enteric or controlled drug release polymer. In this study, tablets containing 10 mg methylene blue as a model drug were prepared with a rotary press. Those tablets were coated with mixtures of shellac and one of the pectin different types (i.e. CU 201, CU 501, CU 701 and CU 020) mostly in a 2:1 ratio or with pure shellac in a small scale fluidized bed apparatus. A stable, simple and reproducible three-stage coating process was successfully developed. The drug contents of the coated tablets were determined using UV-VIS spectrophotometer. The characterization of the surface and the film thickness were performed with the scanning electron microscopy (SEM) and the light microscopy. Release studies were performed in a dissolution apparatus with a basket. Most of the formulations were enteric coated. The dissolution profiles showed a delayed or sustained release with a lagtime of at least 4 h. Dissolution profiles of coated tablets with pure shellac had a very long lagtime ranging from 13 to 17.5 h and the slopes were quite high. The duration of the lagtime and the slope of the dissolution profiles could be adjusted by adding the proper type of pectin to the shellac formulation and by variation of the coating amount. In order to apply a coating formulation as a colon delivery system, the prepared film should be resistant against gastric fluid for at least 2 h and against intestinal fluid for 4-6 h. The required delay time was gained with most of the shellac-pectin polymer mixtures. The release profiles were fitted with the modified model of the Korsmeyer-Peppas equation and the Hixson-Crowell model. A correlation coefficient (R²) > 0.99 was obtained by Korsmeyer-Peppas equation.

Keywords: shellac, pectin, coating, fluidized bed, release, colon delivery system, kinetic, SEM, methylene blue

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2033 High Temperature Oxidation of Additively Manufactured Silicon Carbide/Carbon Fiber Nanocomposites

Authors: Saja M. Nabat Al-Ajrash, Charles Browning, Rose Eckerle, Li Cao, Robyn L. Bradford, Donald Klosterman

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An additive manufacturing process and subsequent pyrolysis cycle were used to fabricate SiC matrix/carbon fiber hybrid composites. The matrix was fabricated using a mixture of preceramic polymer and acrylate monomers, while polyacrylonitrile (PAN) precursor was used to fabricate fibers via electrospinning. The precursor matrix and reinforcing fibers at 0, 2, 5, or 10 wt% were printed using digital light processing, and both were simultaneously pyrolyzed to yield the final ceramic matrix composite structure. After pyrolysis, XRD and SEAD analysis proved the existence of SiC nanocrystals and turbostratic carbon structure in the matrix, while the reinforcement phase was shown to have a turbostratic carbon structure similar to commercial carbon fibers. Thermogravimetric analysis (TGA) in the air up to 1400 °C was used to evaluate the oxidation resistance of this material. TGA results showed some weight loss due to oxidation of SiC and/or carbon up to about 900 °C, followed by weight gain to about 1200 °C due to the formation of a protective SiO2 layer. Although increasing carbon fiber content negatively impacted the total mass loss for the first heating cycle, exposure of the composite to second-run air revealed negligible weight chance. This is explained by SiO2 layer formation, which acts as a protective film that prevents oxygen diffusion. Oxidation of SiC and the formation of a glassy layer has been proven to protect the sample from further oxidation, as well as provide healing of surface cracks and defects, as revealed by SEM analysis.

Keywords: silicon carbide, carbon fibers, additive manufacturing, composite

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2032 Fishing Waste: A Source of Valuable Products through Anaerobic Treatments

Authors: Luisa Maria Arrechea Fajardo, Luz Stella Cadavid Rodriguez

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Fish is one of the most commercialized foods worldwide. However, this industry only takes advantage of about 55% of the product's weight, the rest is converted into waste, which is mainly composed of viscera, gills, scales and spines. Consequently, if these wastes are not used or disposed of properly, they cause serious environmental impacts. This is the case of Tumaco (Colombia), the second largest producer of marine fisheries on the Colombian Pacific coast, where artisanal fishermen process more than 50% of the commercialized volume. There, fishing waste is disposed primarily in the ocean, causing negative impacts on the environment and society. Therefore, in the present research, a proposal was made to take advantage of fishing waste through anaerobic treatments, through which it is possible to obtain products with high added value from organic waste. The research was carried out in four stages. First, the production of volatile fatty acids (VFA) in semi-continuous 4L reactors was studied, evaluating three hydraulic retention times (HRT) (10, 7 and 5 days) with four organic loading rates (OLR) (16, 14, 12 and 10 gVS/L/day), the experiment was carried out for 150 days. Subsequently, biogas production was evaluated from the solid digestate generated in the VFA production reactors, initially evaluating the biochemical methane potential (BMP) of 4 total solid concentrations (1, 2, 4 and 6% TS), for 40 days and then, with the optimum TS concentration (2 gVS/L/day), 2 HRT (15 and 20 days) in semi-continuous reactors, were evaluated for 100 days. Finally, the integration of the processes was carried out with the best conditions found, a first phase of VFA production from fishing waste and a second phase of biogas production from unrecovered VFAs and unprocessed material Additionally, an VFA membrane extraction system was included. In the first phase, a liquid digestate with a concentration and VFA production yield of 59.04 gVFA/L and 0.527 gVFA/gVS, respectively, was obtained, with the best condition found (HRT:7 days and OLR: 16 gVS/L/día), where acetic acid and isobutyric acid were the predominant acids. In the second phase of biogas production, a BMP of 0.349 Nm3CH4/KgVS was reached, and it was found as best HRT 20 days. In the integration, the isovaleric, butyric and isobutyric acid were the VFA with the highest percentage of extraction, additionally a 106.67% increase in biogas production was achieved. This research shows that anaerobic treatments are a promising technology for an environmentally safe management of fishing waste and presents the basis of a possible biorefinery.

Keywords: biogas production, fishing waste, VFA membrane extraction, VFA production

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2031 Factors Contributing to Farmers’ Attitude Towards Climate Adaptation Farming Practices: A Farm Level Study in Bangladesh

Authors: Md Rezaul Karim, Farha Taznin

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The purpose of this study was to assess and describe the individual and household characteristics of farmers, to measure the attitude of farmers towards climate adaptation farming practices and to explore the individual and household factors contributing in predicting their attitude towards climate adaptation farming practices. Data were collected through personal interviews using a pre-tested interview schedule. The data collection was done at Biral Upazila under Dinajpur district in Bangladesh from 1st November to 15 December 2018. Besides descriptive statistical parameters, Pearson’s Product Moment Correlation Coefficient (r), multiple regression and step-wise multiple regression analysis were used for the statistical analysis. Findings indicated that the highest proportion (77.6 percent) of the farmers had moderately favorable attitudes, followed by only 11.2 percent with highly favorable attitudes and 11.2 percent with slightly favorable attitudes towards climate adaptation farming practices. According to the computed correlation coefficients (r), among the 10 selected factors, five of them, such as education of household head, farm size, annual household income, organizational participation, and information access by extension services, had a significant relationship with the attitude of farmers towards climate-smart practices. The step-wise multiple regression results showed that two characteristics as education of household head and information access by extension services, contributed 26.2% and 5.1%, respectively, in predicting farmers' attitudes towards climate adaptation farming practices. In addition, more than two-thirds of farmers cited their opinion to the problems in response to ‘price of vermi species is high and it is not easily available’ as 1st ranked problem, followed by ‘lack of information for innovative climate-smart technologies’. This study suggests that policy implications are necessary to promote extension education and information services and overcome the obstacles to climate adaptation farming practices. It further recommends that research study should be conducted in diverse contexts of nationally or globally.

Keywords: factors, attitude, climate adaptation, farming practices, Bangladesh

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2030 Using Environmental Life Cycle Assessment to Design Sustainable Packaging

Authors: Timothy Francis Grant

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There are conflicting purposes at play with the design of sustainable packaging which include material reduction, recycling compatibility, use of secondary content and performance of the package in protecting and delivering the product. Life Cycle Assessment (LCA) is able to evaluate these different strategies against environmental metrics such as climate change, land and water use and marine litter pollution. However, LCA has traditionally been too time consuming and expensive to be used effectively in packaging design process. To make LCA practical for packaging technologist and designers a simplified tool is needed to make LCA possible for non-environmental specialists. The Packaging Quick Evaluation Tool (PIQET) is a web-based solution for undertaking LCA of new and existing packaging designs considering the global supply chain and impacts from cradle to grave. PIQET is based on a pre-calculated LCA database covering the materials and processes involved in the packaging lifecycle from cradle to grave. This includes both virgin materials and recycled content, conversion of materials into packaging, and the transportation of packaging to the product filling. In addition, PIQET assesses the impacts once the package is filled looking at storage, transport and product loss through the supply chain. When applied to consumer packaging light weight packages which are note recyclable have lower impacts than more recyclable packages which have a higher mass. Its also apparent that for many products the impacts of product failure and product loss are more important environmentally compared to packaging material efficiency.

Keywords: Climate change, Life Cycle Assessment, Marine litter, Packaging sustainability

Procedia PDF Downloads 122
2029 GIS Model for Sanitary Landfill Site Selection Based on Geotechnical Parameters

Authors: Hecson Christian, Joel Macwan

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Landfill site selection in an urban area is a critical issue in the planning process. With the growth of the urbanization, it has a mammoth impact on the economy, ecology, and environmental health of the region. Outsized amount of wastes are produced and the problem gets soared every day. Hence, selection of ideal site for sanitary landfill is a challenge for urban planners and solid waste managers. Disposal site is a function of many parameters. Among all, Geotechnical parameters are very vital as the same is related to surrounding open land. Moreover, the accessible safe and acceptable land is also scarce. Therefore, in this paper geotechnical parameters are used to develop a GIS model to identify an ideal location for landfill purpose. Metropolitan city of Surat is highly populated and fastest growing urban area in India. The research objectives are to conduct field experiments to collect data and to transfer the facts in GIS platform to evolve a model, to find ideal location. Planners’ preferences were obtained to use analytical hierarchical process (AHP) to find weights of each parameter. Integration of GIS and Multi-Criteria Decision Analysis (MCDA) techniques are applied to improve decision-making. It augments an environment for transformation and combination of geographical data and planners’ preferences. GIS performs deterministic overlay and buffer operations. MCDA methods evaluate alternatives based on the decision makers’ subjective values and priorities. Research results have shown many alternative locations. Economic analysis of selected site from actual operations point of view is not included in this research.

Keywords: GIS, AHP, MCDA, Geo-technical

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2028 Quantum Engine Proposal using Two-level Atom Like Manipulation and Relativistic Motoring Control

Authors: Montree Bunruangses, Sonath Bhattacharyya, Somchat Sonasang, Preecha Yupapin

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A two-level system is manipulated by a microstrip add-drop circuit configured as an atom like system for wave-particle behavior investigation when its traveling speed along the circuit perimeter is the speed of light. The entangled pair formed by the upper and lower sideband peaks is bound by the angular displacement, which is given by 0≤θ≤π/2. The control signals associated with 3-peak signal frequencies are applied by the external inputs via the microstrip add-drop multiplexer ports, where they are time functions without the space term involved. When a system satisfies the speed of light conditions, the mass term has been changed to energy based on the relativistic limit described by the Lorentz factor and Einstein equation. The different applied frequencies can be utilized to form the 3-phase torques that can be applied for quantum engines. The experiment will use the two-level system circuit and be conducted in the laboratory. The 3-phase torques will be recorded and investigated for quantum engine driving purpose. The obtained results will be compared to the simulation. The optimum amplification of torque can be obtained by the resonant successive filtering operation. Torque will be vanished when the system is balanced at the stopped position, where |Time|=0, which is required to be a system stability condition. It will be discussed for future applications. A larger device may be tested in the future for realistic use. A synchronous and asynchronous driven motor is also discussed for the warp drive use.

Keywords: quantum engine, relativistic motor, 3-phase torque, atomic engine

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2027 Competing Interactions, and Magnetization Dynamics in Doped Rare-Earth Manganites Nanostructural System

Authors: Wiqar Hussain Shah

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The Structural, magnetic and transport behavior of La1-xCaxMnO3+ (x=0.48, 0.50, 0.52 and 0.55 and =0.015) compositions close to charge ordering, was studied through XRD, resistivity, DC magnetization and AC susceptibility measurements. With time and thermal cycling (T<300 K) there is an irreversible transformation of the low-temperature phase from a partially ferromagnetic and metallic to one that is less ferromagnetic and highly resistive. For instance, an increase of resistivity can be observed by thermal cycling, where no effect is obtained for lower Ca concentration. The time changes in the magnetization are logarithmic in general and activation energies are consistent with those expected for electron transfer between Mn ions. The data suggest that oxygen non-stoichiometry results in mechanical strains in this two-phase system, leading to the development of irreversible metastable states, which relax towards the more stable charge-ordered and antiferromagnetic microdomains at the nano-meter size. This behavior is interpreted in terms of strains induced charge localization at the interface between FM/AFM domains in the antiferromagnetic matrix. Charge, orbital ordering and phase separation play a prominent role in the appearance of such properties, since they can be modified in a spectacular manner by external factor, making the different physical properties metastable. Here we describe two factors that deeply modify those properties, viz. the doping concentration and the thermal cycling. The metastable state is recovered by the high temperature annealing. We also measure the magnetic relaxation in the metastable state and also the revival of the metastable state (in a relaxed sample) due to high temperature (800 ) thermal treatment.

Keywords: Rare-earth maganites, nano-structural materials, doping effects on electrical, magnetic properties, competing interactions

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2026 Numerical investigation of Hydrodynamic and Parietal Heat Transfer to Bingham Fluid Agitated in a Vessel by Helical Ribbon Impeller

Authors: Mounir Baccar, Amel Gammoudi, Abdelhak Ayadi

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The efficient mixing of highly viscous fluids is required for many industries such as food, polymers or paints production. The homogeneity is a challenging operation for this fluids type since they operate at low Reynolds number to reduce the required power of the used impellers. Particularly, close-clearance impellers, mainly helical ribbons, are chosen for highly viscous fluids agitated in laminar regime which is currently heated through vessel wall. Indeed, they are characterized by high shear strains closer to the vessel wall, which causes a disturbing thermal boundary layer and ensures the homogenization of the bulk volume by axial and radial vortices. The hydrodynamic and thermal behaviors of Newtonian fluids in vessels agitated by helical ribbon impellers, has been mostly studied by many researchers. However, rarely researchers investigated numerically the agitation of yield stress fluid by means of helical ribbon impellers. This paper aims to study the effect of the Double Helical Ribbon (DHR) stirrers on both the hydrodynamic and the thermal behaviors of yield stress fluids treated in a cylindrical vessel by means of numerical simulation approach. For this purpose, continuity, momentum, and thermal equations were solved by means of 3D finite volume technique. The effect of Oldroyd (Od) and Reynolds (Re) numbers on the power (Po) and Nusselt (Nu) numbers for the mentioned stirrer type have been studied. Also, the velocity and thermal fields, the dissipation function and the apparent viscosity have been presented in different (r-z) and (r-θ) planes.

Keywords: Bingham fluid, Hydrodynamic and thermal behavior, helical ribbon, mixing, numerical modelling

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2025 Antioxidant Property of Honey with Dried Cherry

Authors: Jasna M. Čanadanović-Brunet, Gordana S. Ćetković, Jelena J. Vulić, Sonja M. Djilas, Vesna T. Tumbas Šaponjac, Sladjana M. Stajčić

Abstract:

Honey serves as a source of natural antioxidants, which are effective in reducing the risk of heart disease, cancer, immune-system decline, cataracts, different inflammatory processes, and also prevent deteriorative oxidation reactions in foods such as enzymatic browning of fruit and vegetables. Honey is a natural saturated sugar solution, but it also contains certain minor constituents, proteins, enzymes, amino and organic acids, lipids, vitamins, phenolic acids, flavonoids and carotenoids. It is consumed in its natural form alone, but also in combination with nuts and various kinds of dried fruits. The aim of this research was to investigate the contribution of dried cherry on phenols (TPh) and flavonoids (Fl) contents and antioxidant activities of honey. Phenolic compounds in Serbian polyfloral (PH), linden (LH) and acacia (AH) honey and also in their mixtures with dried cherry, in 40% mass concentrations (PH40; LH40, AH40), were determined. In comparison to honey, TPh increased 2.25 times for LH40, 2.16 times for AH40 and 1.45 times for PH40, while Fl increased 2.81-fold for PH40, 1.21-fold for LH40 and 1.44-fold for AH40. Antioxidant activity was investigated with two assays, DPPH test and reducing power (RP), and expressed as EC50DPPH and RP0.5 values. The EC50DPPH values were: EC50PH40 = 1.16 mg/ml; EC50LH40= 1.42 mg/ml and EC50AH40= 1.69 mg/ml, while RP0.5 were: RP0.5PH40 = 15.05 mg/ml; RP0.5LH40 = 16.09 mg/ml and P0.5AH40 = 17.60 mg/ml. Our results indicate that supplementation of polyfloral, linden and acacia honey with 40% dried cherry improves antioxidant activity of honey by enriching the phenolic composition.

Keywords: antioxidant activity, dried cherry, honey, phenolics

Procedia PDF Downloads 290
2024 Evaluation of the Effect of Milk Recording Intervals on the Accuracy of an Empirical Model Fitted to Dairy Sheep Lactations

Authors: L. Guevara, Glória L. S., Corea E. E, A. Ramírez-Zamora M., Salinas-Martinez J. A., Angeles-Hernandez J. C.

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Mathematical models are useful for identifying the characteristics of sheep lactation curves to develop and implement improved strategies. However, the accuracy of these models is influenced by factors such as the recording regime, mainly the intervals between test day records (TDR). The current study aimed to evaluate the effect of different TDR intervals on the goodness of fit of the Wood model (WM) applied to dairy sheep lactations. A total of 4,494 weekly TDRs from 156 lactations of dairy crossbred sheep were analyzed. Three new databases were generated from the original weekly TDR data (7D), comprising intervals of 14(14D), 21(21D), and 28(28D) days. The parameters of WM were estimated using the “minpack.lm” package in the R software. The shape of the lactation curve (typical and atypical) was defined based on the WM parameters. The goodness of fit was evaluated using the mean square of prediction error (MSPE), Root of MSPE (RMSPE), Akaike´s Information Criterion (AIC), Bayesian´s Information Criterion (BIC), and the coefficient of correlation (r) between the actual and estimated total milk yield (TMY). WM showed an adequate estimate of TMY regardless of the TDR interval (P=0.21) and shape of the lactation curve (P=0.42). However, we found higher values of r for typical curves compared to atypical curves (0.9vs.0.74), with the highest values for the 28D interval (r=0.95). In the same way, we observed an overestimated peak yield (0.92vs.6.6 l) and underestimated time of peak yield (21.5vs.1.46) in atypical curves. The best values of RMSPE were observed for the 28D interval in both lactation curve shapes. The significant lowest values of AIC (P=0.001) and BIC (P=0.001) were shown by the 7D interval for typical and atypical curves. These results represent the first approach to define the adequate interval to record the regime of dairy sheep in Latin America and showed a better fitting for the Wood model using a 7D interval. However, it is possible to obtain good estimates of TMY using a 28D interval, which reduces the sampling frequency and would save additional costs to dairy sheep producers.

Keywords: gamma incomplete, ewes, shape curves, modeling

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2023 In silico and in vitro Investigation of the Role of Acinetobacter baumannii in the Pathogenesis of Multiple Sclerosis

Authors: Kieren Luellman, Makenzi Rockwell, Eduardo Callegari, Nichole Haag, Chun Wu

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Multiple sclerosis (MS) is an autoimmune disorder that damages the myelin sheath of neurons in the central nervous system. The presence of Acinetobacter bacteria and anti-Acinetobacter antibodies in MS patients has led to the hypothesis that the bacteria may contribute to MS pathogenesis. In this study, the protein sequences of Acinetobacter baumannii were compared to five peptides from three mammalian myelin proteins, i.e., Proteolipid Protein (PLP): PLP 139-151, PLP 178-191, Myelin Basic Protein (MBP): MBP 84-104 and Myelin Oligodendrocyte Glycoprotein (MOG): MOG 35-55 and MOG 92-106 respectively, known to induce experimental autoimmune encephalomyelitis (EAE), a condition similar to MS. We found 11 hits (i.e., with five or more amino acid sequence similarity) in Acinetobacter baumannii, which are identical or similar to PLP139-151, 32 hits to PLP178-191, 35 to MBP 84-104, 41 hits to MOG 35-55 and 26 hits to MOG92-106. In addition, Western blotting was used to assess possible interaction between the bacterial proteins and human anti-MBP, anti-MOG, and anti-PLP antibodies produced in rabbits, corresponding to MBP 84-104, MOG 35-55, and PLP 139-151, respectively. We found that both human Polyclonal anti-MOG antibody and anti-PLP antibody recognized a protein or more proteins of the same molecular mass of around 25 kDa. in Acinetobacter baumannii. The results suggested that this/these protein(s) might potentially serve as antigen(s) to induce anti-MOG antibody and anti-PLP antibody production in mammalian B cells. The proteomic study identified 433 hits, among which the sequence of Acinetobacter baumannii protein 491 subunit A matches a previously published enzyme Acinetobacter 3-Oxoadipate CoA-Transferase, in which a fragment of its peptide was observed to recognize MS patient serum via ELISA method. Our findings might pave the road to understanding one of the pathogenesis mechanisms of MS.

Keywords: multiple sclerosis, pathogenesis, Acinetobacter baumannii, antibody recognition

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