Search results for: thermal burden
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4262

Search results for: thermal burden

572 The Evaluation of the Performance of CaCO3/Polymer Nano-Composites for the Preservation of Historic Limestone Monuments

Authors: Mohammed Badereldien, Rezk Diab, Mohamoud Ali, Ayman Aboelkassem

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The stone surfaces of historical architectural heritage in Egypt are under threat from of various environmental factors such as temperature fluctuation, humidity, pollution, and microbes. Due to these factors, the facades of buildings are deteriorating deformation and disfiguration of external decoration and the formation of black accretion also often from the stone works. The aim of this study is to evaluate the effectiveness of CaCO₃ nano-particles as consolidation and protection material for calcareous stone monuments. Selected tests were carried out in order to estimate the superficial consolidating and protective effect of the treatment. When applied the nanoparticles dispersed in the acrylic copolymer; poly ethylmethacrylate (EMA)/methylacrylate (MA) (70/30, respectively) (EMA)/methylacrylate (MA) (70/30, respectively). The synthesis process of CaCO₃ nanoparticles/polymer nano-composite was prepared using in situ emulsion polymerization system. The consolidation and protection were characterized by TEM, while the penetration depth, re-aggregating effects of the deposited phase, and the surface morphology before and after treatment were examined by SEM (Scanning Electron Microscopy). Improvement of the stones' mechanical properties was evaluated by compressive strength tests. Changes in water-interaction properties were evaluated by water absorption capillarity measurements, and colorimetric measurements were used to evaluate the optical appearance. Together the results appear to demonstrate that CaCO₃/polymer nanocomposite is an efficient material for the consolidation of limestone architecture and monuments. As compared with samples treated with pure acrylic copolymer without Calcium carbonate nanoparticles, for example, CaCO₃ nanoparticles are completely compatible, strengthening limestone against thermal aging and improving its mechanical properties.

Keywords: calcium carbonate nanoparticles, consolidation, nanocomposites, calcareous stone, colorimetric measurements, compressive strength

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571 Treatment of Acid Mine Lake by Ultrasonically Modified Fly Ash at Different Frequencies

Authors: Burcu Ileri, Deniz Sanliyuksel Yucel, Onder Ayyildiz

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The oxidation of pyrite in water results in the formation of acid mine drainage, which typically forms extremely acid mine lake (AML) in the depression areas of abandoned Etili open-pit coal mine site, Northwest Turkey. Nine acid mine lakes of various sizes have been located in the Etili coal mine site. Hayirtepe AML is one of the oldest lake having a mean pH value of 2.9 and conductivity of 4550 μS/cm, and containing elevated concentrations of Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn. The water quality of the lake has been deteriorated due to its high chemical composition, in particular, increasing heavy metal pollution. In this study, fly ash (FA), a coal combustion by-product from fluidized bed thermal power plant in the northwestern part of Turkey, was used as an adsorbent for the treatment of Hayirtepe AML. The FA is a relatively abundant and cost effective material, but its use in adsorption processes usually require excessive adsorbent doses. To increase adsorption efficiency and lower the adsorbent dose, we modified the FA by means of ultrasonic treatment (20 kHz and 40 kHz). The images of scanning electron microscopy (SEM) have demonstrated that ultrasonic treatment not only decreased the size of ash particles but also created pits and cracks on their surfaces which in turn led to a significant increase in the BET surface area. Both FA and modified fly ash were later tested for the removal of heavy metals from the AML. The effect of various operating parameters such as ultrasonic power, pH, ash dose, and adsorption contact time were examined to obtain the optimum conditions for the treatment process. The results have demonstrated that removal of heavy metals by ultrasound-modified fly ash requires much shorter treatment times and lower adsorbent doses than those attained by the unmodified fly ash. This research was financially supported by the Scientific and Technological Research Council of Turkey (TUBITAK), (Project no: 116Y510).

Keywords: acid mine lake, heavy metal, modified fly ash, ultrasonic treatment

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570 Dwindling the Stability of DNA Sequence by Base Substitution at Intersection of COMT and MIR4761 Gene

Authors: Srishty Gulati, Anju Singh, Shrikant Kukreti

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The manifestation of structural polymorphism in DNA depends on the sequence and surrounding environment. Ample of folded DNA structures have been found in the cellular system out of which DNA hairpins are very common, however, are indispensable due to their role in the replication initiation sites, recombination, transcription regulation, and protein recognition. We enumerate this approach in our study, where the two base substitutions and change in temperature embark destabilization of DNA structure and misbalance the equilibrium between two structures of a sequence present at the overlapping region of the human COMT gene and MIR4761 gene. COMT and MIR4761 gene encodes for catechol-O-methyltransferase (COMT) enzyme and microRNAs (miRNAs), respectively. Environmental changes and errors during cell division lead to genetic abnormalities. The COMT gene entailed in dopamine regulation fosters neurological diseases like Parkinson's disease, schizophrenia, velocardiofacial syndrome, etc. A 19-mer deoxyoligonucleotide sequence 5'-AGGACAAGGTGTGCATGCC-3' (COMT19) is located at exon-4 on chromosome 22 and band q11.2 at the intersection of COMT and MIR4761 gene. Bioinformatics studies suggest that this sequence is conserved in humans and few other organisms and is involved in recognition of transcription factors in the vicinity of 3'-end. Non-denaturating gel electrophoresis and CD spectroscopy of COMT sequences indicate the formation of hairpin type DNA structures. Temperature-dependent CD studies revealed an unusual shift in the slipped DNA-Hairpin DNA equilibrium with the change in temperature. Also, UV-thermal melting techniques suggest that the two base substitutions on the complementary strand of COMT19 did not affect the structure but reduces the stability of duplex. This study gives insight about the possibility of existing structurally polymorphic transient states within DNA segments present at the intersection of COMT and MIR4761 gene.

Keywords: base-substitution, catechol-o-methyltransferase (COMT), hairpin-DNA, structural polymorphism

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569 Optimization and Kinetic Analysis of the Enzymatic Hydrolysis of Oil Palm Empty Fruit Bunch To Xylose Using Crude Xylanase from Trichoderma Viride ITB CC L.67

Authors: Efri Mardawati, Ronny Purwadi, Made Tri Ari Penia Kresnowati, Tjandra Setiadi

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EFB are mainly composed of cellulose (≈ 43%), hemicellulose (≈ 23%) and lignin (≈20%). The palm oil empty fruit bunches (EFB) is the lignosellulosic waste from crude palm oil industries mainly compose of (≈ 43%), hemicellulose (≈ 23%) and lignin (≈20%). Xylan, a polymer made of pentose sugar xylose and the most abundant component of hemicellulose in plant cell wall. Further xylose can be used as a raw material for production of a wide variety of chemicals such as xylitol, which is extensively used in food, pharmaceutical and thin coating applications. Currently, xylose is mostly produced from xylan via chemical hydrolysis processes. However, these processes are normally conducted at a high temperature and pressure, which is costly, and the required downstream processes are relatively complex. As an alternative method, enzymatic hydrolysis of xylan to xylose offers an environmentally friendly biotechnological process, which is performed at ambient temperature and pressure with high specificity and at low cost. This process is catalysed by xylanolytic enzymes that can be produced by some fungal species such as Aspergillus niger, Penicillium crysogenum, Tricoderma reseei, etc. Fungal that will be used to produce crude xylanase enzyme in this study is T. Viride ITB CC L.67. It is the purposes of this research to study the influence of pretreatment of EFB for the enzymatic hydrolysis process, optimation of temperature and pH of the hydrolysis process, the influence of substrate and enzyme concentration to the enzymatic hydrolysis process, the dynamics of hydrolysis process and followingly to study the kinetics of this process. Xylose as the product of enzymatic hydrolysis process analyzed by HPLC. The results show that the thermal pretreatment of EFB enhance the enzymatic hydrolysis process. The enzymatic hydrolysis can be well approached by the Michaelis Menten kinetic model, and kinetic parameters are obtained from experimental data.

Keywords: oil palm empty fruit bunches (EFB), xylose, enzymatic hydrolysis, kinetic modelling

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568 Anti-Inflammatory, Anti-Nociceptive and Anti-Arthritic Effects of Mirtazapine, Venalfaxine and Escitalopram in Rats

Authors: Sally A. El Awdan

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Objective and Design: The purpose of this study was to evaluate the anti inflammatory, anti-arthritic and analgesic effects of antidepressants. Methods: Carrageenan model was used to assess effect on acute inflammation. Paw volume were measured at 1, 2, 3 and 4th hour post challenge. Anti-nociceptive effect was evaluated by hot plate method. Chronic inflammation was developed using Complete Freund's Adjuvant (CFA). The animals were injected with Freund’s adjuvant in sub-plantar tissue of the right posterior paw. Paw volume, ankle flexion scores, adjuvant-induced hyperalgesia and serum cytokine levels were assessed. Results: Results obtained demonstrate that mirtazapine, venalfaxine and escitalopram significantly and dose-dependently inhibited carrageenan-induced rat paw oedema. Mirtazapine, venalfaxine and escitalopram increased the reaction time of rats in hot plate test. We observed an increase in paw volume, ankle flexion scores, thermal hyperalgesia, serum levels of interleukin-1β, PGE2 and TNF-α, induced by intraplantar CFA injection. Regular treatment up to 28 days of adjuvant-induced arthritic rats with mirtazapine, venalfaxine and escitalopram showed anti anti-inflammatory and analgesic activities by suppressing the paw volume, recovering the paw withdrawal latency, and by inhibiting the ankle flexion scores in CFA-induced rats. In addition significant reduction in serum levels of interleukin-1β, PGE2 and TNF-α level in arthritic rats was reduced by treatment with drugs. Conclusion: These results suggest that antidepressants have significant anti-inflammatory and anti-nociceptive effects in acute and chronic models in rats, which may be associated with the reduction of interleukin-1β, PGE2 and TNF-α levels.

Keywords: antidepressants, carrageenan, anti-nociceptive, Complete Freund's Adjuvant

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567 Influence of UV Aging on the Mechanical Properties of Polycarbonate

Authors: S. Redjala, N. Ait Hocine, M. Gratton, N. Poirot, R. Ferhoum, S. Azem

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Polycarbonate (PC) is a promising polymer with high transparency in the range of the visible spectrum and is used in various fields, for example medical, electronic, automotive. Its low weight, chemical inertia, high impact resistance and relatively low cost are of major importance. In recent decades, some materials such as metals and ceramics have been replaced by polymers because of their superior advantages. However, some characteristics of the polymers are highly modified under the effect of ultraviolet (UV) radiation and temperature. The changes induced in the material by such aging depend on the exposure time, the wavelength of the UV radiation and the temperature level. The UV energy is sufficient to break the chemical bonds leading to a cleavage of the molecular chains. This causes changes in the mechanical, thermal, optical and morphological properties of the material. The present work is focused on the study of the effects of aging under ultraviolet (UV) radiation and under different temperature values on the physical-chemical and mechanical properties of a PC. Thus, various investigations, such as FTIR and XRD analyses, SEM and optical microscopy observations, micro-hardness measurements and monotonic and cyclic tensile tests, were carried out on the PC in the initial state and after aging. Results have shown the impact of aging on the properties of the PC studied. In fact, the MEB highlighted changes in the superficial morphology of the material by the presence of cracks and material de-bonding in the form of debris. The FTIR spectra reveal an attenuation of the peaks like the hydroxyl (OH) groups located at 3520 cm-1. The XRD lines shift towards a larger angle, reaching a maximum of 3°. In addition, Vickers micro-hardness measurements show that aging affects the surface and the core of the material, which results in different mechanical behaviours under monotonic and cyclic tensile tests. This study pointed out effects of aging on the macroscopic properties of the PC studied, in relationship with its microstructural changes.

Keywords: mechanical properties, physical-chemical properties, polycarbonate, UV aging, temperature aging

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566 Land Suitability Assessment for Vineyards in Afghanistan Based on Physical and Socio-Economic Criteria

Authors: Sara Tokhi Arab, Tariq Salari, Ryozo Noguchi, Tofael Ahamed

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Land suitability analysis is essential for table grape cultivation in order to increase its production and productivity under the dry condition of Afghanistan. In this context, the main aim of this paper was to determine the suitable locations for vineyards based on satellite remote sensing and GIS (geographical information system) in Kabul Province of Afghanistan. The Landsat8 OLI (operational land imager) and thermal infrared sensor (TIRS) and shuttle radar topography mission digital elevation model (SRTM DEM) images were processed to obtain the normalized difference vegetation index (NDVI), normalized difference moisture index (NDMI), land surface temperature (LST), and topographic criteria (elevation, aspect, and slope). Moreover, Jaxa rainfall (mm per hour), soil properties information are also used for the physical suitability of vineyards. Besides, socio-economic criteria were collected through field surveys from Kabul Province in order to develop the socio-economic suitability map. Finally, the suitable classes were determined using weighted overly based on a reclassification of each criterion based on AHP (Analytical Hierarchy Process) weights. The results indicated that only 11.1% of areas were highly suitable, 24.8% were moderately suitable, 35.7% were marginally suitable and 28.4% were not physically suitable for grapes production. However, 15.7% were highly suitable, 17.6% were moderately suitable, 28.4% were marginally suitable and 38.3% were not socio-economically suitable for table grapes production in Kabul Province. This research could help decision-makers, growers, and other stakeholders with conducting precise land assessments by identifying the main limiting factors for the production of table grapes management and able to increase land productivity more precisely.

Keywords: vineyards, land physical suitability, socio-economic suitability, AHP

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565 Theoretical Prediction on the Lifetime of Sessile Evaporating Droplet in Blade Cooling

Authors: Yang Shen, Yongpan Cheng, Jinliang Xu

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The effective blade cooling is of great significance for improving the performance of turbine. The mist cooling emerges as the promising way compared with the transitional single-phase cooling. In the mist cooling, the injected droplet will evaporate rapidly, and cool down the blade surface due to the absorbed latent heat, hence the lifetime for evaporating droplet becomes critical for design of cooling passages for the blade. So far there have been extensive studies on the droplet evaporation, but usually the isothermal model is applied for most of the studies. Actually the surface cooling effect can affect the droplet evaporation greatly, it can prolong the droplet evaporation lifetime significantly. In our study, a new theoretical model for sessile droplet evaporation with surface cooling effect is built up in toroidal coordinate. Three evaporation modes are analyzed during the evaporation lifetime, include “Constant Contact Radius”(CCR) mode、“Constant Contact Angle”(CCA) mode and “stick-slip”(SS) mode. The dimensionless number E0 is introduced to indicate the strength of the evaporative cooling, it is defined based on the thermal properties of the liquid and the atmosphere. Our model can predict accurately the lifetime of evaporation by validating with available experimental data. Then the temporal variation of droplet volume, contact angle and contact radius are presented under CCR, CCA and SS mode, the following conclusions are obtained. 1) The larger the dimensionless number E0, the longer the lifetime of three evaporation cases is; 2) The droplet volume over time still follows “2/3 power law” in the CCA mode, as in the isothermal model without the cooling effect; 3) In the “SS” mode, the large transition contact angle can reduce the evaporation time in CCR mode, and increase the time in CCA mode, the overall lifetime will be increased; 4) The correction factor for predicting instantaneous volume of the droplet is derived to predict the droplet life time accurately. These findings may be of great significance to explore the dynamics and heat transfer of sessile droplet evaporation.

Keywords: blade cooling, droplet evaporation, lifetime, theoretical analysis

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564 Elucidating Microstructural Evolution Mechanisms in Tungsten via Layerwise Rolling in Additive Manufacturing: An Integrated Simulation and Experimental Approach

Authors: Sadman Durlov, Aditya Ganesh-Ram, Hamidreza Hekmatjou, Md Najmus Salehin, Nora Shayesteh Ameri

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In the field of additive manufacturing, tungsten stands out for its exceptional resistance to high temperatures, making it an ideal candidate for use in extreme conditions. However, its inherent brittleness and vulnerability to thermal cracking pose significant challenges to its manufacturability. This study explores the microstructural evolution of tungsten processed through layer-wise rolling in laser powder bed fusion additive manufacturing, utilizing a comprehensive approach that combines advanced simulation techniques with empirical research. We aim to uncover the complex processes of plastic deformation and microstructural transformations, with a particular focus on the dynamics of grain size, boundary evolution, and phase distribution. Our methodology employs a combination of simulation and experimental data, allowing for a detailed comparison that elucidates the key mechanisms influencing microstructural alterations during the rolling process. This approach facilitates a deeper understanding of the material's behavior under additive manufacturing conditions, specifically in terms of deformation and recrystallization. The insights derived from this research not only deepen our theoretical knowledge but also provide actionable strategies for refining manufacturing parameters to improve the tungsten components' mechanical properties and functional performance. By integrating simulation with practical experimentation, this study significantly enhances the field of materials science, offering a robust framework for the development of durable materials suited for challenging operational environments. Our findings pave the way for optimizing additive manufacturing techniques and expanding the use of tungsten across various demanding sectors.

Keywords: additive manufacturing, layer wise rolling, refractory materials, in-situ microstructure modifications

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563 Yield and Composition of Bio-Oil from Co-Pyrolysis of Corn Cobs and Plastic Waste of HDPE in a Fixed Bed Reactor

Authors: Dijan Supramono, Eny Kusrini, Haisya Yuana

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Pyrolysis, a thermal cracking process in inert environment, may be used to produce bio-oil from biomass and plastic waste thus accommodating the use of renewable energy. Abundant amount of biomass waste in Indonesia are not utilised and plastic wastes are not well processed for clean environment. The aim of present work was to evaluate effect of mass ratio of plastic material to biomass in the feed blend of corn cobs and high density polyethylene (HDPE) of co-pyrolysis on bio-oil yield and chemical composition of bio-oil products. The heating rate of the co-pyrolysis was kept low and residence time was in the order of seconds to accommodate high yield of oil originating from plastic pyrolysis. Corn cobs have high cellulose and hemicellulose content (84%) which is potential to produce bio-oil. The pyrolysis was conducted in a laboratory-scale using a fixed bed reactor with final temperature of 500°C, heating rate 5 °C/min, flow rate N2 750 mL/min, total weight of biomass and plastic material of 20 g, and hold time after peak temperature of 30 min. Set up of conditions of co-pyrolysis should lead to accommodating the production of oil originating from HDPE due to constraint of HDPE pyrolysis residence time. Mass ratio of plastics to biomass in the feed blend was varied 0:100, 25:75, 50:50, 75:25 and 100:0. It was found that by increasing HDPE content up to 100% in the feed blend, the yield of bio-oil at different mass ratios prescribed above were 28.05, 21.55, 14.55, 9.5, and 6.3wt%, respectively. Therefore, in the fixed bed reactor, producing bio-oil is constrained by low contribution of plastic feedstock to the pyrolysis liquid yield. Furthermore, for the same variation of the mass ratio, yields of the mixture of paraffins, olefins and cycloalkanes contained in bio-oil were of 0, 28.35, 40.75, 47.17, and 67.05wt%, respectively. Olefins and cycloalkanes are easily hydrogenised to produce paraffins, suitable to be used as bio-fuel. By increasing composition of HDPE in the feed blend, viscosity and pH of bio-oil change approaching to those of commercial diesel oil.

Keywords: co-pyrolysis, corn cobs, fixed bed reactor, HDPE

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562 Application of Artificial Neural Network for Single Horizontal Bare Tube and Bare Tube Bundles (Staggered) of Large Particles: Heat Transfer Prediction

Authors: G. Ravindranath, S. Savitha

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This paper presents heat transfer analysis of single horizontal bare tube and heat transfer analysis of staggered arrangement of bare tube bundles bare tube bundles in gas-solid (air-solid) fluidized bed and predictions are done by using Artificial Neural Network (ANN) based on experimental data. Fluidized bed provide nearly isothermal environment with high heat transfer rate to submerged objects i.e. due to through mixing and large contact area between the gas and the particle, a fully fluidized bed has little temperature variation and gas leaves at a temperature which is close to that of the bed. Measurement of average heat transfer coefficient was made by local thermal simulation technique in a cold bubbling air-fluidized bed of size 0.305 m. x 0.305 m. Studies were conducted for single horizontal Bare Tube of length 305mm and 28.6mm outer diameter and for bare tube bundles of staggered arrangement using beds of large (average particle diameter greater than 1 mm) particle (raagi and mustard). Within the range of experimental conditions influence of bed particle diameter ( Dp), Fluidizing Velocity (U) were studied, which are significant parameters affecting heat transfer. Artificial Neural Networks (ANNs) have been receiving an increasing attention for simulating engineering systems due to some interesting characteristics such as learning capability, fault tolerance, and non-linearity. Here, feed-forward architecture and trained by back-propagation technique is adopted to predict heat transfer analysis found from experimental results. The ANN is designed to suit the present system which has 3 inputs and 2 out puts. The network predictions are found to be in very good agreement with the experimental observed values of bare heat transfer coefficient (hb) and nusselt number of bare tube (Nub).

Keywords: fluidized bed, large particles, particle diameter, ANN

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561 Factors Affecting Treatment Resilience in Patients with Oesophago-Gastric Cancers Undergoing Palliative Chemotherapy: A Literature Review

Authors: Kiran Datta, Daniella Holland-Hart, Anthony Byrne

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Introduction: Oesophago-gastric (OG) cancers are the fifth commonest in the UK, accounting for over 12,000 deaths each year. Most patients will present at later stages of the disease, with only 21% of patients with stage 4 disease surviving longer than a year. As a result, many patients are unsuitable for curative surgery and instead receive palliative treatment to improve prognosis and symptom burden. However, palliative chemotherapy can result in significant toxicity: almost half of the patients are unable to complete their chemotherapy regimen, with this proportion rising significantly in older and frailer patients. In addition, clinical trials often exclude older and frailer patients due to strict inclusion criteria, meaning there is limited evidence to guide which patients are most likely to benefit from palliative chemotherapy. Inappropriate chemotherapy administration is at odds with the goals of palliative treatment and care, which are to improve quality of life, and this also represents a significant resource expenditure. This literature review aimed to examine and appraise evidence regarding treatment resilience in order to guide clinicians in identifying the most suitable candidates for palliative chemotherapy. Factors influencing treatment resilience were assessed, as measured by completion rates, dose reductions, and toxicities. Methods: This literature review was conducted using rapid review methodology, utilising modified systematic methods. A literature search was performed across the MEDLINE, EMBASE, and Cochrane Library databases, with results limited to papers within the last 15 years and available in English. Key inclusion criteria included: 1) participants with either oesophageal, gastro-oesophageal junction, or gastric cancers; 2) patients treated with palliative chemotherapy; 3) available data evaluating the association between baseline participant characteristics and treatment resilience. Results: Of the 2326 papers returned, 11 reports of 10 studies were included in this review after excluding duplicates and irrelevant papers. Treatment resilience factors that were assessed included: age, performance status, frailty, inflammatory markers, and sarcopenia. Age was generally a poor predictor for how well patients would tolerate chemotherapy, while poor performance status was a better indicator of the need for dose reduction and treatment non-completion. Frailty was assessed across one cohort using multiple screening tools and was an effective marker of the risk of toxicity and the requirement for dose reduction. Inflammatory markers included lymphopenia and the Glasgow Prognostic Score, which assessed inflammation and hypoalbuminaemia. Although quick to obtain and interpret, these findings appeared less reliable due to the inclusion of patients treated with palliative radiotherapy. Sarcopenia and body composition were often associated with chemotherapy toxicity but not the rate of regimen completion. Conclusion: This review demonstrates that there are numerous measures that can estimate the ability of patients with oesophago-gastric cancer to tolerate palliative chemotherapy, and these should be incorporated into clinical assessments to promote personalised decision-making around treatment. Age should not be a barrier to receiving chemotherapy and older and frailer patients should be included in future clinical trials to better represent typical patients with oesophago-gastric cancers. Decisions regarding palliative treatment should be guided by these factors identified as well as patient preference.

Keywords: frailty, oesophago-gastric cancer, palliative chemotherapy, treatment resilience

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560 Skin-to-Skin Contact Simulation: Improving Health Outcomes for Medically Fragile Newborns in the Neonatal Intensive Care Unit

Authors: Gabriella Zarlenga, Martha L. Hall

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Introduction: Premature infants are at risk for neurodevelopmental deficits and hospital readmissions, which can increase the financial burden on the health care system and families. Kangaroo care (skin-to-skin contact) is a practice that can improve preterm infant health outcomes. Preterm infants can acquire adequate body temperature, heartbeat, and breathing regulation through lying directly on the mother’s abdomen and in between her breasts. Due to some infant’s condition, kangaroo care is not a feasible intervention. The purpose of this proof-of-concept research project is to create a device which simulates skin-to-skin contact for pre-term infants not eligible for kangaroo care, with the aim of promoting baby’s health outcomes, reducing the incidence of serious neonatal and early childhood illnesses, and/or improving cognitive, social and emotional aspects of development. Methods: The study design is a proof-of-concept based on a three-phase approach; (1) observational study and data analysis of the standard of care for 2 groups of pre-term infants, (2) design and concept development of a novel device for pre-term infants not currently eligible for standard kangaroo care, and (3) prototyping, laboratory testing, and evaluation of the novel device in comparison to current assessment parameters of kangaroo care. A single center study will be conducted in an area hospital offering Level III neonatal intensive care. Eligible participants include newborns born premature (28-30 weeks of age) admitted to the NICU. The study design includes 2 groups: a control group receiving standard kangaroo care and an experimental group not eligible for kangaroo care. Based on behavioral analysis of observational video data collected in the NICU, the device will be created to simulate mother’s body using electrical components in a thermoplastic polymer housing covered in silicone. It will be designed with a microprocessor that controls simulated respiration, heartbeat, and body temperature of the 'simulated caregiver' by using a pneumatic lung, vibration sensors (heartbeat), pressure sensors (weight/position), and resistive film to measure temperature. A slight contour of the simulator surface may be integrated to help position the infant correctly. Control and monitoring of the skin-to-skin contact simulator would be performed locally by an integrated touchscreen. The unit would have built-in Wi-Fi connectivity as well as an optional Bluetooth connection in which the respiration and heart rate could be synced with a parent or caregiver. A camera would be integrated, allowing a video stream of the infant in the simulator to be streamed to a monitoring location. Findings: Expected outcomes are stabilization of respiratory and cardiac rates, thermoregulation of those infants not eligible for skin to skin contact with their mothers, and real time mother Bluetooth to the device to mimic the experience in the womb. Results of this study will benefit clinical practice by creating a new standard of care for premature neonates in the NICU that are deprived of skin to skin contact due to various health restrictions.

Keywords: kangaroo care, wearable technology, pre-term infants, medical design

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559 Microwave Assisted Rapid Synthesis of Nano-Binder from Renewable Resource and Their Application in Textile Printing

Authors: K. Haggag, N. S. Elshemy

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Due to limited fossil resource and an increased need for environmentally friendly, sustainable technologies, the importance of using renewable feed stocks in textile industry area will increase in the decades to come. This research highlights some of the perspectives in this area. Alkyd resins for high characterization and reactive properties, completely based on commercially available renewable resources (sunflower and/or soybean oil) were prepared and characterized. In this work, we present results on the synthesis of various alkyd resins according to the alcoholysis – polyesterification process under different preparation conditions using a microwave synthesis as energy source to determine suitable reaction conditions. Effects of polymerization parameters, such as catalyst ratio, reaction temperature and microwave power level have been studied. The prepared binder was characterized via FT-IR, scanning electron microscope (SEM) and transmission electron microscope (TEM), in addition to acid value (AV), iodine value (IV), water absorbance, weight loss, and glass transition temperature. The prepared binder showed high performance physico-mechanical properties. TEM analysis showed that the polymer latex nanoparticle within range of 20–200 nm. The study involved the application of the prepared alkyd resins as binder for pigment printing process onto cotton fabric by using a flat screen technique and the prints were dried and thermal cured. The optimum curing conditions were determined, color strength and fastness properties of pigment printed areas to light, washing, perspiration and crocking were evaluated. The rheological properties and apparent viscosity of prepared binders were measured in addition roughness of the prints was also determined.

Keywords: nano-binder, microwave heating, renewable resource, alkyd resins, sunflower oil, soybean oil

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558 Study of Nanoclay Blends Based on PET/PEN Prepared by Reactive Extrusion

Authors: F. Zouai, F. Z. Benabid, S. Bouhelal, D. Benachour

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A new route of preparation of compatible blends, based on poly(ethylene terephthalate)(PET)/poly(ethylenenaphthalene2,6-dicarboxylate) (PEN)/clay nanocomposites has been successfully performed in one step by reactive melt extrusion. To achieve this, untreated clay was first purified and functionalized “in situ” with a compound based on an organic peroxide/sulfur mixture and (tetra methyl thiuram disulfide) TMTD as accelerator or activator for sulfur. The PET and PEN materials were first mixed separately in the melt state with different amounts of functionalized clay. It was observed that the compositions PET/4 wt% clay and PEN/7.5 wt% clay showed total exfoliation. These completely exfoliated compositions, called nPET and nPEN, respectively, were used to prepare new nPET/nPEN nanoblends in the same mixing batch. The nPET/nPEN nanoblends were compared to neat blends of PET/PEN. The blends and the nanocomposites were characterized by different techniques: differential scanning calorimetry (DSC) and wide-angle X-ray scattering (WAXS). The micro and nanostructure/properties relationships were investigated. The results of the WAXS measurements study showed that the exfoliation of tetrahedral nanolayers of clay was complete and the octahedral structure disappeared totally. From the different WAXS patterns, it is seen that all samples are amorphous phase. The thermal study showed that there are only one glass transition temperature Tg, one crystallization temperature Tc and one melting temperature Tm for every composition. This indicated that both PET/PEN blends and nPET/nPEN blends were compatible in the entire range of compositions. In addition, nPET/nPEN blends present lower Tc values and higher Tm values than the corresponding neat PET/PEN blends. The obtained results indicate that nPET/nPEN blends are somewhat different from the pure ones in nanostructure and behavior, thus showing the additional effect of nanolayers. The present study allowed establishing good correlations between the different measured properties.

Keywords: PET, PEN, montmorillonite, nanocomposites, exfoliation, reactive melt-mixing

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557 Broad Host Range Bacteriophage Cocktail for Reduction of Staphylococcus aureus as Potential Therapy for Atopic Dermatitis

Authors: Tamar Lin, Nufar Buchshtab, Yifat Elharar, Julian Nicenboim, Rotem Edgar, Iddo Weiner, Lior Zelcbuch, Ariel Cohen, Sharon Kredo-Russo, Inbar Gahali-Sass, Naomi Zak, Sailaja Puttagunta, Merav Bassan

Abstract:

Background: Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin disorder that is characterized by dry skin and flares of eczematous lesions and intense pruritus. Multiple lines of evidence suggest that AD is associated with increased colonization by Staphylococcus aureus, which contributes to disease pathogenesis through the release of virulence factors that affect both keratinocytes and immune cells, leading to disruption of the skin barrier and immune cell dysfunction. The aim of the current study is to develop a bacteriophage-based product that specifically targets S. aureus. Methods: For the discovery of phage, environmental samples were screened on 118 S. aureus strains isolated from skin samples, followed by multiple enrichment steps. Natural phages were isolated, subjected to Next-generation Sequencing (NGS), and analyzed using proprietary bioinformatics tools for undesirable genes (toxins, antibiotic resistance genes, lysogeny potential), taxonomic classification, and purity. Phage host range was determined by an efficiency of plating (EOP) value above 0.1 and the ability of the cocktail to completely lyse liquid bacterial culture under different growth conditions (e.g., temperature, bacterial stage). Results: Sequencing analysis demonstrated that the 118 S. aureus clinical strains were distributed across the phylogenetic tree of all available Refseq S. aureus (~10,750 strains). Screening environmental samples on the S. aureus isolates resulted in the isolation of 50 lytic phages from different genera, including Silviavirus, Kayvirus, Podoviridae, and a novel unidentified phage. NGS sequencing confirmed the absence of toxic elements in the phages’ genomes. The host range of the individual phages, as measured by the efficiency of plating (EOP), ranged between 41% (48/118) to 79% (93/118). Host range studies in liquid culture revealed that a subset of the phages can infect a broad range of S. aureus strains in different metabolic states, including stationary state. Combining the single-phage EOP results of selected phages resulted in a broad host range cocktail which infected 92% (109/118) of the strains. When tested in vitro in a liquid infection assay, clearance was achieved in 87% (103/118) of the strains, with no evidence of phage resistance throughout the study (24 hours). A S. aureus host was identified that can be used for the production of all the phages in the cocktail at high titers suitable for large-scale manufacturing. This host was validated for the absence of contaminating prophages using advanced NGS methods combined with multiple production cycles. The phages are produced under optimized scale-up conditions and are being used for the development of a topical formulation (BX005) that may be administered to subjects with atopic dermatitis. Conclusions: A cocktail of natural phages targeting S. aureus was effective in reducing bacterial burden across multiple assays. Phage products may offer safe and effective steroid-sparing options for atopic dermatitis.

Keywords: atopic dermatitis, bacteriophage cocktail, host range, Staphylococcus aureus

Procedia PDF Downloads 144
556 Removal of Rhodamine B from Aqueous Solution Using Natural Clay by Fixed Bed Column Method

Authors: A. Ghribi, M. Bagane

Abstract:

The discharge of dye in industrial effluents is of great concern because their presence and accumulation have a toxic or carcinogenic effect on living species. The removal of such compounds at such low levels is a difficult problem. The adsorption process is an effective and attractive proposition for the treatment of dye contaminated wastewater. Activated carbon adsorption in fixed beds is a very common technology in the treatment of water and especially in processes of decolouration. However, it is expensive and the powdered one is difficult to be separated from aquatic system when it becomes exhausted or the effluent reaches the maximum allowable discharge level. The regeneration of exhausted activated carbon by chemical and thermal procedure is also expensive and results in loss of the sorbent. The focus of this research was to evaluate the adsorption potential of the raw clay in removing rhodamine B from aqueous solutions using a laboratory fixed-bed column. The continuous sorption process was conducted in this study in order to simulate industrial conditions. The effect of process parameters, such as inlet flow rate, adsorbent bed height, and initial adsorbate concentration on the shape of breakthrough curves was investigated. A glass column with an internal diameter of 1.5 cm and height of 30 cm was used as a fixed-bed column. The pH of feed solution was set at 8.5. Experiments were carried out at different bed heights (5 - 20 cm), influent flow rates (1.6- 8 mL/min) and influent rhodamine B concentrations (20 - 80 mg/L). The obtained results showed that the adsorption capacity increases with the bed depth and the initial concentration and it decreases at higher flow rate. The column regeneration was possible for four adsorption–desorption cycles. The clay column study states the value of the excellent adsorption capacity for the removal of rhodamine B from aqueous solution. Uptake of rhodamine B through a fixed-bed column was dependent on the bed depth, influent rhodamine B concentration, and flow rate.

Keywords: adsorption, breakthrough curve, clay, fixed bed column, rhodamine b, regeneration

Procedia PDF Downloads 264
555 Physiological Response of Water-Restricted Xhosa Goats Supplemented with Vitamin C

Authors: O.F. Akinmoladun, F.N. Fon, C.T. Mpendulo, O. Okoh

Abstract:

The sustainability of livestock production is under threat as a result of water scarcity, fluctuating precipitation, and high environmental temperature. These combined stressors have impacted negatively on general animal production and welfare, necessitating a very reliable and cost-effective management practices, especially in arid and water-limited regions of the world. Instead of the above, this study was designed to investigate the growth performance and physiological response of water-restricted Xhosa ear-lobe goats fed diets supplemented with single or multiple vitamin C (VC) during summer. The total forty-eight goats used for the experiment were balanced for body weight and randomly assigned to the seven treatment groups (seven goats/treatment): GI (W100%); GII (W70%); GIII (W50%); GIV (W70%+3g/day VC); GV ((W50% +3g/day VC); GVI (W70%+3g/d VC+extra 5g on every eight-day); GVII (W50%+3g/d VC+extra 5g on every eight-day). The design was a complete randomized design and VC was administered per os. At the end of the 75-day feeding trial, GIII (W50%) animals were the most affected (P<0.05) and the effect was more pronounced in their body condition scores (BCs). Weight loss and depression in feed intake due to water restriction (P<0.05) were attenuated by VC treated groups (GIV-GVII). Changes in body thermal gradient (BTG) and rectal temperature (RcT) were similar (P>0.05) across the various experimental groups. The attenuation effect of VC was significant in responses to respiratory rate (RR) and cortisol. Supplementation of VC (either single or multiple) did not significantly (P>0.05) improve water restriction effect on body condition scores (BCs) and FAMACHA©. The current study found out that Xhosa ear lobe goats can adapt to the prevailing bioclimatic changes and limited water intake. However, supplementation of vitamin C can be beneficial at modulating these stressful stimuli. Continuous consistencies in the outcome of vitamin C on water-stressed animals can help validate recommendations especially to farmers in the arid and water-limited regions across the globe.

Keywords: vitamin C, Xhosa ear-lobe, thermotolerance, water stress

Procedia PDF Downloads 119
554 Synthesis and Gas Transport Properties of Polynorbornene Dicarboximides Bearing Trifluoromethyl Isomer Moieties

Authors: Jorge A. Cruz-Morales, Joel Vargas, Arlette A. Santiago, Mikhail A. Tlenkopatchev

Abstract:

In industrial processes such as oil extraction and refining, products are handled or generated in the gas phase, which represents a challenge in terms of treatment and purification. During the past three decades, new scientific findings and technological advances in separation based on the use of membranes have led to simpler and more efficient gas separation processes, optimizing the use of energy and generating less pollution. This work reports the synthesis and ring-opening metathesis polymerization (ROMP) of new structural isomers based on norbornene dicarboximides bearing trifluoromethyl moieties, specifically N-2-trifluoromethylphenyl-exo,endo-norbornene-5,6-dicarboximide (2a) and N-3-trifluoromethylphenyl-exo,endo-norbornene-5,6-dicarboximide (2b), using tricyclohexylphosphine [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene] ruthenium dichloride (I), bis(tricyclohexylphosphine) benzylidene ruthenium (IV) dichloride (II), and bis(tricyclohexylphosphine) p-fluorophenylvinylidene ruthenium (II) dichloride (III). It was observed that the -CF3 moiety attached at the ortho position of the aromatic ring increases thermal and mechanical properties of the polymer, whereas meta substitution has the opposite effect. A comparative study of gas transportation in membranes, based on these fluorinated polynorbornenes, showed that -CF3 ortho substitution increases permeability of the polymer membrane as a consequence of the increase in both gas solubility and gas diffusion. In contrast, gas permeability coefficients of the meta-substituted polymer membrane are rather similar to those of that which is non-fluorinated; this can be attributed to a lower fractional free volume. The meta-substituted polymer membrane, besides showing the largest permselectivity coefficients of all the isomers studied here, was also found to have one of the largest permselectivity coefficients for separating H2/C3H6 into glassy polynorbornene dicarboximides.

Keywords: gas transport membranes, polynorbornene dicarboximide, ROMP, structural isomers

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553 Synthesis and Properties of Chitosan-Graft-Polyacrylamide/Gelatin Superabsorbent Composites for Wastewater Purification

Authors: Hafida Ferfera-Harrar, Nacera Aiouaz, Nassima Dairi

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Super absorbents polymers received much attention and are used in many fields because of their superior characters to traditional absorbents, e.g., sponge and cotton. So, it is very important but challenging to prepare highly and fast-swelling super absorbents. A reliable, efficient and low-cost technique for removing heavy metal ions from waste water is the adsorption using bio-adsorbents obtained from biological materials, such as polysaccharides-based hydrogels super absorbents. In this study, novel multi-functional super absorbent composites type semi-interpenetrating polymer networks (Semi-IPNs) were prepared via graft polymerization of acrylamide onto chitosan backbone in presence of gelatin, CTS-g-PAAm/Ge, using potassium persulfate and N,N’ -methylenebisacrylamide as initiator and cross linker, respectively. These hydrogels were also partially hydrolyzed to achieve superabsorbents with ampholytic properties and uppermost swelling capacity. The formation of the grafted network was evidenced by Fourier Transform Infrared Spectroscopy (ATR-FTIR) and thermo gravimetric Analysis (TGA). The porous structures were observed by Scanning Electron Microscope (SEM). From TGA analysis, it was concluded that the incorporation of the Ge in the CTS-g-PAAm network has marginally affected its thermal stability. The effect of gelatin content on the swelling capacities of these super absorbent composites was examined in various media (distilled water, saline and pH-solutions).The water absorbency was enhanced by adding Ge in the network, where the optimum value was reached at 2 wt. % of Ge. Their hydrolysis has not only greatly optimized their absorption capacity but also improved the swelling kinetic. These materials have also showed reswelling ability. We believe that these super-absorbing materials would be very effective for the adsorption of harmful metal ions from waste water.

Keywords: chitosan, gelatin, superabsorbent, water absorbency

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552 From Modelled Design to Reality through Material and Machinery Lab and Field Tests: Porous Concrete Carparks at the Wanda Metropolitano Stadium in Madrid

Authors: Manuel de Pazos-Liano, Manuel Cifuentes-Antonio, Juan Fisac-Gozalo, Sara Perales-Momparler, Carlos Martinez-Montero

Abstract:

The first-ever game in the Wanda Metropolitano Stadium, the new home of the Club Atletico de Madrid, was played on September 16, 2017, thanks to the work of a multidisciplinary team that made it possible to combine urban development with sustainability goals. The new football ground sits on a 1.2 km² land owned by the city of Madrid. Its construction has dramatically increased the sealed area of the site (transforming the runoff coefficient from 0.35 to 0.9), and the surrounding sewer network has no capacity for that extra flow. As an alternative to enlarge the existing 2.5 m diameter pipes, it was decided to detain runoff on site by means of an integrated and durable infrastructure that would not blow up the construction cost nor represent a burden on the municipality’s maintenance tasks. Instead of the more conventional option of building a large concrete detention tank, the decision was taken on the use of pervious pavement on the 3013 car parking spaces for sub-surface water storage, a solution aligned with the city water ordinance and the Madrid + Natural project. Making the idea a reality, in only five months and during the summer season (which forced to pour the porous concrete only overnight), was a challenge never faced before in Spain, that required of innovation both at the material as well as the machinery side. The process consisted on: a) defining the characteristics required for the porous concrete (compressive strength of 15 N/mm2 and 20% voids); b) testing of different porous concrete dosages at the construction company laboratory; c) stablishing the cross section in order to provide structural strength and sufficient water detention capacity (20 cm porous concrete over a 5 cm 5/10 gravel, that sits on a 50 cm coarse 40/50 aggregate sub-base separated by a virgin fiber polypropylene geotextile fabric); d) hydraulic computer modelling (using the Full Hydrograph Method based on the Wallingford Procedure) to estimate design peak flows decrease (an average of 69% at the three car parking lots); e) use of a variety of machinery for the application of the porous concrete to achieve both structural strength and permeable surface (including an inverse rotating rolling imported from USA, and the so-called CMI, a sliding concrete paver used in the construction of motorways with rigid pavements); f) full-scale pilots and final construction testing by an accredited laboratory (pavement compressive strength average value of 15 N/mm2 and 0,0032 m/s permeability). The continuous testing and innovating construction process explained in detail within this article, allowed for a growing performance with time, finally proving the use of the CMI valid also for large porous car park applications. All this process resulted in a successful story that converts the Wanda Metropolitano Stadium into a great demonstration site that will help the application of the Spanish Royal Decree 638/2016 (it also counts with rainwater harvesting for grass irrigation).

Keywords: construction machinery, permeable carpark, porous concrete, SUDS, sustainable develpoment

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551 An Evaluation of the Feasibility of Several Industrial Wastes and Natural Materials as Precursors for the Production of Alkali Activated Materials

Authors: O. Alelweet, S. Pavia

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In order to face current compelling environmental problems affecting the planet, the construction industry needs to adapt. It is widely acknowledged that there is a need for durable, high-performance, low-greenhouse gas emission binders that can be used as an alternative to Portland cement (PC) to lower the environmental impact of construction. Alkali activated materials (AAMs) are considered a more sustainable alternative to PC materials. The binders of AAMs result from the reaction of an alkali metal source and a silicate powder or precursor which can be a calcium silicate or an aluminosilicate-rich material. This paper evaluates the particle size, specific surface area, chemical and mineral composition and amorphousness of silicate materials (most industrial waste locally produced in Ireland and Saudi Arabia) to develop alkali-activated binders that can replace PC resources in specific applications. These include recycled ceramic brick, bauxite, illitic clay, fly ash and metallurgical slag. According to the results, the wastes are reactive and comply with building standards requirements. The study also evidenced that the reactivity of the Saudi bauxite (with significant kaolinite) can be enhanced on thermal activation; and high calcium in the slag will promote reaction; which should be possible with low alkalinity activators. The wastes evidenced variable water demands that will be taken into account for mixing with the activators. Finally, further research is proposed to further determine the reactive fraction of the clay-based precursors.

Keywords: alkali activated materials, alkali-activated binders, sustainable building materials, recycled ceramic brick, bauxite, red mud, clay, fly ash, metallurgical slags, particle size, chemical and mineral composition and amorphousness, water demand, particle density

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550 Effect of Carbon Nanotubes on Ultraviolet and Immersion Stability of Diglycidyl Ether of Bisphenol A Epoxy Coating

Authors: Artemova Anastasiia, Shen Zexiang, Savilov Serguei

Abstract:

The marine environment is very aggressive for a number of factors, such as moisture, temperature, winds, ultraviolet radiation, chloride ion concentration, oxygen concentration, pollution, and biofouling, all contributing to marine corrosion. Protective organic coatings provide protection either by a barrier action from the layer, which is limited due to permeability to water and oxygen or from active corrosion inhibition and cathodic protection due to the pigments in the coating. Carbon nanotubes can play not only barrier effect but also passivation effect via adsorbing molecular species of oxygen, hydroxyl, chloride and sulphate anions. Multiwall carbon nanotubes composite provide very important properties such as mechanical strength, non-cytotoxicity, outstanding thermal and electrical conductivity, and very strong absorption of ultraviolet radiation. The samples of stainless steel (316L) coated by epoxy resin with carbon nanotubes-based pigments were exposed to UV irradiation (340nm), and immersion to the sodium chloride solution for 1000h and corrosion behavior in 3.5 wt% sodium chloride (NaCl) solution was investigated. Experimental results showed that corrosion current significantly decreased in the presence of carbon nanotube-based materials, especially nitrogen-doped ones, in the composite coating. Importance of the structure and composition of the pigment materials and its composition was established, and the mechanism of the protection was described. Finally, the effect of nitrogen doping on the corrosion behavior was investigated. The pigment-polymer crosslinking improves the coating performance and the corrosion rate decreases in comparison with pure epoxy coating from 5.7E-05 to 1.4E-05mm/yr for the coating without any degradation; in more than 6 times for the coating after ultraviolet degradation; and more than 16% for the coatings after immersion degradation.

Keywords: corrosion, coating, carbon nanotubes, degradation

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549 Conduction Transfer Functions for the Calculation of Heat Demands in Heavyweight Facade Systems

Authors: Mergim Gasia, Bojan Milovanovica, Sanjin Gumbarevic

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Better energy performance of the building envelope is one of the most important aspects of energy savings if the goals set by the European Union are to be achieved in the future. Dynamic heat transfer simulations are being used for the calculation of building energy consumption because they give more realistic energy demands compared to the stationary calculations that do not take the building’s thermal mass into account. Software used for these dynamic simulation use methods that are based on the analytical models since numerical models are insufficient for longer periods. The analytical models used in this research fall in the category of the conduction transfer functions (CTFs). Two methods for calculating the CTFs covered by this research are the Laplace method and the State-Space method. The literature review showed that the main disadvantage of these methods is that they are inadequate for heavyweight façade elements and shorter time periods used for the calculation. The algorithms for both the Laplace and State-Space methods are implemented in Mathematica, and the results are compared to the results from EnergyPlus and TRNSYS since these software use similar algorithms for the calculation of the building’s energy demand. This research aims to check the efficiency of the Laplace and the State-Space method for calculating the building’s energy demand for heavyweight building elements and shorter sampling time, and it also gives the means for the improvement of the algorithms used by these methods. As the reference point for the boundary heat flux density, the finite difference method (FDM) is used. Even though the dynamic heat transfer simulations are superior to the calculation based on the stationary boundary conditions, they have their limitations and will give unsatisfactory results if not properly used.

Keywords: Laplace method, state-space method, conduction transfer functions, finite difference method

Procedia PDF Downloads 115
548 Electrochemotherapy of Portal Vein Tumor Thrombus as Dowstaging to Liver Transplantation

Authors: Luciano Tarantino, Emanuele Balzano, Paolo Tarantino, Riccardo Aurelio Nasto, Aurelio Nasto

Abstract:

Liver transplantation (OLT) is contraindicate in Portal Vein tumor Thrombosis (PVTT) from Hepatocellular Carcinoma at hepatic hilum(pH-HCC) Surgery,Thermal ablation and chemotherapy show poorer outcomes Electrochemotherapy (ECT) has been successfully used in patients with pH-HCC with PVTT. We report the results of ECT as downstaging aimed to definitive cure by OLT. F.P. 53 years HBV related Cirrhosis Child-Pugh B7 class; EGDS F2 aesophageal Varices. Diabetes. April 2016 : Enhanced Computed Tomography (CT) detected HCC(n.3 nodules in VII-VIII-VI;diameter range=25 cm) and PVTT of right portal vein. The patient was considered ineligible for OLT. May 2016: first ablation session with percutaneous Radiofrequency-ablation(RFA) of 3 HCC-nodules . August 2016: second ablation session with ECT of PVTT. CT october 2016: disappearance of PVTT and patent right portal vein. No intraparenchymal recurrence. CT march 2017: No recurrence in portal vein and in the left lobe. local recurrence in the VII-VIII segments. May 2017 : transarterial chemoembolization (TACE) of right lobe recurrences. CT October 2017: patent right portal vein. No recurrence. The patient was reconsidered for OLT. He underwent OLT in April 2018. At 36-months follow-up , no intrahepatic recurrence of HCC occurred. March 2021: enhanced CT and PET/CT detected a single small nodule (1.5 cm) uptaking tracer in the left upper pulmonary lobe, no hepatic recurrence . CT-guided FNB showed metastasis from HCC . June 2021: left lung upper lobectomy . At the current time the patient is alive and recurrence-free at 64 months follow-up. ECT Could be aneffective technique as pre-OLT dowstaging in HCC with PVTT.

Keywords: liver tumor ablation, interventional ultrasound, electrochemotherapy, liver transplantation

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547 Synthesis, Characterization, and Catalytic Application of Modified Hierarchical Zeolites

Authors: A. Feliczak Guzik, I. Nowak

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Zeolites, classified as microporous materials, are a large group of crystalline aluminosilicate materials commonly used in the chemical industry. These materials are characterized by large specific surface area, high adsorption capacity, hydrothermal and thermal stability. However, the micropores present in them impose strong mass transfer limitations, resulting in low catalytic performance. Consequently, mesoporous (hierarchical) zeolites have attracted considerable attention from researchers. These materials possess additional porosity in the mesopore size region (2-50 nm according to IUPAC). Mesoporous zeolites, based on commercial MFI-type zeolites modified with silver, were synthesized as follows: 0.5 g of zeolite was dispersed in a mixture containing CTABr (template), water, ethanol, and ammonia under ultrasound for 30 min at 65°C. The silicon source, which was tetraethyl orthosilicate, was then added and stirred for 4 h. After this time, silver(I) nitrate was added. In a further step, the whole mixture was filtered and washed with water: ethanol mixture. The template was removed by calcination at 550°C for 5h. All the materials obtained were characterized by the following techniques: X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), nitrogen adsorption/desorption isotherms, FTIR spectroscopy. X-ray diffraction and low-temperature nitrogen adsorption/desorption isotherms revealed additional secondary porosity. Moreover, the structure of the commercial zeolite was preserved during most of the material syntheses. The aforementioned materials were used in the epoxidation reaction of cyclohexene using conventional heating and microwave radiation heating. The composition of the reaction mixture was analyzed every 1 h by gas chromatography. As a result, about 60% conversion of cyclohexene and high selectivity to the desired reaction products i.e., 1,2-epoxy cyclohexane and 1,2-cyclohexane diol, were obtained.

Keywords: catalytic application, characterization, epoxidation, hierarchical zeolites, synthesis

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546 A Study on Economic Impacts of Entrepreneurial Firms and Self-Employment: Minority Ethnics in Putatan, Penampang, Inanam, Menggatal, Uitm, Tongod, Sabah, Malaysia

Authors: Lizinis Cassendra Frederick Dony, Jirom Jeremy Frederick Dony, Andrew Nicholas, Dewi Binti Tajuddin

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Starting and surviving a business is influenced by various entrepreneurship socio-economics activities. The study revealed that some of the entrepreneurs are not registered under SME but running own business as an intermediary with the private organization entrusted as “Self-Employed.” SME is known as “Small Medium Enterprise” contributes growth in Malaysia. Therefore, the entrepreneurialism business interest and entrepreneurial intention enhancing new spurring production, expanding employment opportunities, increasing productivity, promoting exports, stimulating innovation and providing new avenue in the business market place. This study has identified the unique contribution to the full understanding of complex mechanisms through entrepreneurship obstacles and education impacts on happiness and well-being to society. Moreover, “Ethnic” term has defined as a curious meaning refers to a classification of a large group of people customs implies to ancestral, racial, national, tribal, religious, linguistic and cultural origins. It is a social phenomenon.1 According to Sabah data population is amounting to 2,389,494 showed the predominant ethnic group being the Kadazan Dusun (18.4%) followed by Bajau (17.3%) and Malays (15.3%). For the year 2010, data statistic immigrants population report showed the amount to 239,765 people which cover 4% of the Sabahan’s population.2 Sabah has numerous group of talented entrepreneurs. The business environment among the minority ethnics are influenced with the business sentiment competition. The literature on ethnic entrepreneurship recognizes two main type entrepreneurships: the middleman and enclave entrepreneurs. According to Adam Smith,3 there are evidently some principles disposition to admire and maintain the distinction business rank status and cause most universal business sentiments. Due to credit barriers competition, the minority ethnics are losing the business market and since 2014, many illegal immigrants have been found to be using permits of the locals to operate businesses in Malaysia.4 The development of small business entrepreneurship among the minority ethnics in Sabah evidenced based variety of complex perception and differences concepts. The studies also confirmed the effects of heterogeneity on group decision and thinking caused partly by excessive pre-occupation with maintaining cohesiveness and the presence of cultural diversity in groups should reduce its probability.5 The researchers proposed that there are seven success determinants particularly to determine the involvement of minority ethnics comparing to the involvement of the immigrants in Sabah. Although, (SMEs) have always been considered the backbone of the economy development, the minority ethnics are often categorized it as the “second-choice.’ The study showed that illegal immigrants entrepreneur imposed a burden on Sabahan social programs as well as the prison, court and health care systems. The tension between the need for cheap labor and the impulse to protect Malaysian in Sabah workers, entrepreneurs and taxpayers, among the subjects discussed in this study. This is clearly can be advantages and disadvantages to the Sabah economic development.

Keywords: entrepreneurial firms, self-employed, immigrants, minority ethnic, economic impacts

Procedia PDF Downloads 397
545 Numerical Study of a Ventilation Principle Based on Flow Pulsations

Authors: Amir Sattari, Mac Panah, Naeim Rashidfarokhi

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To enhance the mixing of fluid in a rectangular enclosure with a circular inlet and outlet, an energy-efficient approach is further investigated through computational fluid dynamics (CFD). Particle image velocimetry (PIV) measurements help confirm that the pulsation of the inflow velocity improves the mixing performance inside the enclosure considerably without increasing energy consumption. In this study, multiple CFD simulations with different turbulent models were performed. The results obtained were compared with experimental PIV results. This study investigates small-scale representations of flow patterns in a ventilated rectangular room. The objective is to validate the concept of an energy-efficient ventilation strategy with improved thermal comfort and reduction of stagnant air inside the room. Experimental and simulated results confirm that through pulsation of the inflow velocity, strong secondary vortices are generated downstream of the entrance wall-jet. The pulsatile inflow profile promotes a periodic generation of vortices with stronger eddies despite a relatively low inlet velocity, which leads to a larger boundary layer with increased kinetic energy in the occupied zone. A real-scale study was not conducted; however, it can be concluded that a constant velocity inflow profile can be replaced with a lower pulsated flow rate profile while preserving the mixing efficiency. Among the turbulent CFD models demonstrated in this study, SST-kω is most advantageous, exhibiting a similar global airflow pattern as in the experiments. The detailed near-wall velocity profile is utilized to identify the wall-jet instabilities that consist of mixing and boundary layers. The SAS method was later applied to predict the turbulent parameters in the center of the domain. In both cases, the predictions are in good agreement with the measured results.

Keywords: CFD, PIV, pulsatile inflow, ventilation, wall-jet

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544 Mental Health Promotion for Children of Mentally Ill Parents in Schools. Assessment and Promotion of Teacher Mental Health Literacy in Order to Promote Child Related Mental Health (Teacher-MHL)

Authors: Dirk Bruland, Paulo Pinheiro, Ullrich Bauer

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Introduction: Over 3 million children, about one quarter of all students, experience at least one parent with mental disorder in Germany every year. Children of mentally-ill parents are at considerably higher risk of developing serious mental health problems. The different burden patterns and coping attempts often become manifest in children's school lives. In this context, schools can have an important protective function, but can also create risk potentials. In reference to Jorm, pupil-related teachers’ mental health literacy (Teacher-MHL) includes the ability to recognize change behaviour, the knowledge of risk factors, the implementation of first aid intervention, and seeking professional help (teacher as gatekeeper). Although teachers’ knowledge and increased awareness of this topic is essential, the literature provides little information on the extent of teachers' abilities. As part of a German-wide research consortium on health literacy, this project, launched in March for 3 years, will conduct evidence-based mental health literacy research. The primary objective is to measure Teacher-MHL in the context of pupil-related psychosocial factors at primary and secondary schools (grades 5 & 6), while also focussing on children’s social living conditions. Methods: (1) A systematic literature review in different databases to identify papers with regard to Teacher-MHL (completed). (2) Based on these results, an interview guide was developed. This research step includes a qualitative pre-study to inductively survey the general profiles of teachers (n=24). The evaluation will be presented on the conference. (3) These findings will be translated into a quantitative teacher survey (n=2500) in order to assess the extent of socio-analytical skills of teachers as well as in relation to institutional and individual characteristics. (4) Based on results 1 – 3, developing a training program for teachers. Results: The review highlights a lack of information for Teacher-MHL and their skills, especially related to high-risk-groups like children of mentally ill parents. The literature is limited to a few studies only. According to these, teacher are not good at identifying burdened children and if they identify those children they do not know how to handle the situations in school. They are not sufficiently trained to deal with these children, especially there are great uncertainties in dealing with the teaching situation. Institutional means and resources are missing as well. Such a mismatch can result in insufficient support and use of opportunities for children at risk. First impressions from the interviews confirm these results and allow a greater insight in the everyday school-life according to critical life events in families. Conclusions: For the first time schools will be addressed as a setting where children are especially "accessible" for measures of health promotion. Addressing Teacher-MHL gives reason to expect high effectiveness. Targeting professionals' abilities for dealing with this high-risk-group leads to a discharge for teacher themselves to handle those situations and increases school health promotion. In view of the fact that only 10-30% of such high-risk families accept offers of therapy and assistance, this will be the first primary preventive and health-promoting approach to protect the health of a yet unaffected, but particularly burdened, high-risk group.

Keywords: children of mentally ill parents, health promotion, mental health literacy, school

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543 Study of the Anaerobic Degradation Potential of High Strength Molasses Wastewater

Authors: M. Mischopoulou, P. Naidis, S. Kalamaras, T. Kotsopoulos, P. Samaras

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The treatment of high strength wastewater by an Upflow Anaerobic Sludge Blanket (UASB) reactor has several benefits, such as high organic removal efficiency, short hydraulic retention time along with low operating costs. In addition, high volumes of biogas are released in these reactors, which can be utilized in several industrial facilities for energy production. This study aims at the examination of the application potential of anaerobic treatment of wastewater, with high molasses content derived from yeast manufacturing, by a lab-scale UASB reactor. The molasses wastewater and the sludge used in the experiments were collected from the wastewater treatment plant of a baker’s yeast manufacturing company. The experimental set-up consisted of a 15 L thermostated UASB reactor at 37 ◦C. Before the reactor start-up, the reactor was filled with sludge and molasses wastewater at a ratio 1:1 v/v. Influent was fed to the reactor at a flowrate of 12 L/d, corresponding to a hydraulic residence time of about 30 h. Effluents were collected from the system outlet and were analyzed for the determination of the following parameters: COD, pH, total solids, volatile solids, ammonium, phosphates and total nitrogen according to the standard methods of analysis. In addition, volatile fatty acid (VFA) composition of the effluent was determined by a gas chromatograph equipped with a flame ionization detector (FID), as an indicator to evaluate the process efficiency. The volume of biogas generated in the reactor was daily measured by the water displacement method, while gas composition was analyzed by a gas chromatograph equipped with a thermal conductivity detector (TCD). The effluent quality was greatly enhanced due to the use of the UASB reactor and high rate of biogas production was observed. The anaerobic treatment of the molasses wastewater by the UASB reactor improved the biodegradation potential of the influent, resulting at high methane yields and an effluent with better quality than the raw wastewater.

Keywords: anaerobic digestion, biogas production, molasses wastewater, UASB reactor

Procedia PDF Downloads 264