Search results for: overlap weight
2444 The Impact Of Türki̇ye’s Decision-making Mechanism On The Transformation In Türkiye-syria Relations (2002-2024)
Authors: Ibrahim Akkan
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This study analyses the transformation of Türkiye's Syria policy between 2002 and 2024 and the impact of domestic political dynamics in this process. Since the collapse of the Ottoman Empire, Türkiye and Syria have had a tense relationship for a long time due to reasons such as border issues, water sharing, security concerns and the activities of terrorist organizations. However, the process that started with the Adana Agreement in 1998 gained momentum with the Justice and Development Party (Ak Party) coming to power in 2002 and a historical period of rapprochement began between the two countries. During this period, Türkiye adopted the concept of “zero problems with neighbors” in its foreign policy and deepened its strategic partnerships in the region. Turkish-Syrian relations also developed within this framework, the trade volume between the two countries increased and cooperation was strengthened through mutual visits and diplomatic agreements. However, the Arab Spring that started in 2011 was a sharp turning point in Turkish-Syrian relations. The harsh stance of the Bashar Assad administration against the popular uprisings in Syria caused Türkiye to take a stance against Assad and support opposition groups. This process led to the severing of diplomatic ties between the two countries and the gradual deterioration of relations until 2024. Türkiye directly intervened in the civil war in Syria after the Arab Spring and conducted military operations in northern Syria that highlighted security policies. The main purpose of this study is to examine the transformation in Türkiye's Syria policies between 2002 and 2024 and to analyze the role of domestic political dynamics in Türkiye in this transformation. The main research question of the study is how domestic political actors in Türkiye, especially decision-makers (leaders, governments, political parties), shape foreign policy. In this context, the extent to which the leadership of the Ak Party government is decisive in decision-making processes and how the impact of domestic dynamics on foreign policy emerges will be studied. In this study, how both the pressures of the international system and domestic political dynamics shape foreign policy will be analyzed using the theoretical framework of neoclassical realism. How decision-making processes are decisive in foreign policy will be examined through a case study specific to Türkiye-Syria relations. In addition, the strategic preferences of leaders such as Recep Tayyip Erdoğan and Ahmet Davutoğlu in foreign policy and how these preferences overlap with developments in domestic politics will be evaluated using the discourse analysis method. This study aims to make a new contribution to the literature by providing a comprehensive analysis of how domestic dynamics shape foreign policy in Türkiye-Syria relations.Keywords: decision-making mechanisms, foreign policy analysis, neoclassical realism, syria, türkiye
Procedia PDF Downloads 42443 Analyzing the Effects of Bio-fibers on the Stiffness and Strength of Adhesively Bonded Thermoplastic Bio-fiber Reinforced Composites by a Mixed Experimental-Numerical Approach
Authors: Sofie Verstraete, Stijn Debruyne, Frederik Desplentere
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Considering environmental issues, the interest to apply sustainable materials in industry increases. Specifically for composites, there is an emerging need for suitable materials and bonding techniques. As an alternative to traditional composites, short bio-fiber (cellulose-based flax) reinforced Polylactic Acid (PLA) is gaining popularity. However, these thermoplastic based composites show issues in adhesive bonding. This research focusses on analyzing the effects of the fibers near the bonding interphase. The research applies injection molded plate structures. A first important parameter concerns the fiber volume fraction, which directly affects adhesion characteristics of the surface. This parameter is varied between 0 (pure PLA) and 30%. Next to fiber volume fraction, the orientation of fibers near the bonding surface governs the adhesion characteristics of the injection molded parts. This parameter is not directly controlled in this work, but its effects are analyzed. Surface roughness also greatly determines surface wettability, thus adhesion. Therefore, this research work considers three different roughness conditions. Different mechanical treatments yield values up to 0.5 mm. In this preliminary research, only one adhesive type is considered. This is a two-part epoxy which is cured at 23 °C for 48 hours. In order to assure a dedicated parametric study, simple and reproduceable adhesive bonds are manufactured. Both single lap (substrate width 25 mm, thickness 3 mm, overlap length 10 mm) and double lap tests are considered since these are well documented and quite straightforward to conduct. These tests are conducted for the different substrate and surface conditions. Dog bone tensile testing is applied to retrieve the stiffness and strength characteristics of the substrates (with different fiber volume fractions). Numerical modelling (non-linear FEA) relates the effects of the considered parameters on the stiffness and strength of the different joints, obtained through the abovementioned tests. Ongoing work deals with developing dedicated numerical models, incorporating the different considered adhesion parameters. Although this work is the start of an extensive research project on the bonding characteristics of thermoplastic bio-fiber reinforced composites, some interesting results are already prominent. Firstly, a clear correlation between the surface roughness and the wettability of the substrates is observed. Given the adhesive type (and viscosity), it is noticed that an increase in surface energy is proportional to the surface roughness, to some extent. This becomes more pronounced when fiber volume fraction increases. Secondly, ultimate bond strength (single lap) also increases with increasing fiber volume fraction. On a macroscopic level, this confirms the positive effect of fibers near the adhesive bond line.Keywords: adhesive bonding, bio-fiber reinforced composite, flax fibers, lap joint
Procedia PDF Downloads 1282442 Fuzzy Sliding Mode Control of a Flexible Structure for Vibration Suppression Using MFC Actuator
Authors: Jinsiang Shaw, Shih-Chieh Tseng
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Active vibration control is good for low frequency excitation, with advantages of light weight and adaptability. This paper use a macro-fiber composite (MFC) actuator for vibration suppression in a cantilevered beam due to its higher output force to suppress the disturbance. A fuzzy sliding mode controller is developed and applied to this system. Experimental results illustrate that the controller and MFC actuator are very effective in attenuating the structural vibration near the first resonant freuqency. Furthermore, this controller is shown to outperform the traditional skyhook controller, with nearly 90% of the vibration suppressed at the first resonant frequency of the structure.Keywords: Fuzzy sliding mode controller, macro-fiber-composite actuator, skyhook controller, vibration suppression
Procedia PDF Downloads 4042441 Effect of Nano-SiO2 Solution on the Strength Characteristics of Kaolinite
Authors: Reza Ziaie Moayed, Hamidreza Rahmani
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Today, with developments in science and technology, there is an excessive potential for the use of nanomaterials in various fields of geotechnical project such as soil stabilization. This study investigates the effect of Nano-SiO2 solution on the unconfined compression strength and Young's elastic modulus of Kaolinite. For this purpose, nano-SiO2 was mixed with kaolinite in five different contents: 1, 2, 3, 4 and 5% by weight of the dry soil and a series of the unconfined compression test with curing time of one-day was selected as laboratory test. Analyses of the tests results show that stabilization of kaolinite with Nano-SiO2 solution can improve effectively the unconfined compression strength of modified soil up to 1.43 times compared to the pure soil.Keywords: kaolinite, Nano-SiO2, stabilization, unconfined compression test, Young's modulus
Procedia PDF Downloads 3912440 The Influence of Nutritional and Immunological Status on the Prognosis of Head and Neck Cancer
Authors: Ching-Yi Yiu, Hui-Chen Hsu
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Objectives: Head and neck cancer (HNC) is a big global health problem in the world. Despite the development of diagnosis and treatment, the overall survival of HNC is still low. The well recognition of the interaction of the host immune system and cancer cells has led to realizing the processes of tumor initiation, progression and metastasis. Many systemic inflammatory responses have been shown to play a crucial role in cancer progression. The pre and post-treatment nutritional and immunological status of HNC patients is a reliable prognostic indicator of tumor outcomes and survivors. Methods: Between July 2020 to June 2022, We have enrolled 60 HNC patients, including 59 males and 1 female, in Chi Mei Medical Center, Liouying, Taiwan. The age distribution was from 37 to 81 years old (y/o), with a mean age of 57.6 y/o. We evaluated the pre-and post-treatment nutritional and immunological status of these HNC patients with body weight, body weight loss, body mass index (BMI), whole blood count including hemoglobin (Hb), lymphocyte, neutrophil and platelet counts, biochemistry including prealbumin, albumin, c-reactive protein (CRP), with the time period of before treatment, post-treatment 3 and 6 months. We calculated the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) to assess how these biomarkers influence the outcomes of HNC patients. Results: We have carcinoma of the hypopharynx in 21 cases with 35%, carcinoma of the larynx in 9 cases, carcinoma of the tonsil and tongue every 6 cases, carcinoma soft palate and tongue base every 5 cases, carcinoma of buccal mucosa, retromolar trigone and mouth floor every 2 cases, carcinoma of the hard palate and low lip each 1 case. There were stage I 15 cases, stage II 13 cases, stage III 6 cases, stage IVA 10 cases, and stage IVB 16 cases. All patients have received surgery, chemoradiation therapy or combined therapy. We have wound infection in 6 cases, 2 cases of pharyngocutaneous fistula, flap necrosis in 2 cases, and mortality in 6 cases. In the wound infection group, the average BMI is 20.4 kg/m2; the average Hb is 12.9 g/dL, the average albumin is 3.5 g/dL, the average NLR is 6.78, and the average PLR is 243.5. In the PC fistula and flap necrosis group, the average BMI is 21.65 kg/m2; the average Hb is 11.7 g/dL, the average albumin is 3.15 g/dL, average NLR is 13.28, average PLR is 418.84. In the mortality group, the average BMI is 22.3 kg/m2; the average Hb is 13.58 g/dL, the average albumin is 3.77 g/dL, the average NLR is 6.06, and the average PLR is 275.5. Conclusion: HNC is a big challenging public health problem worldwide, especially in the high prevalence of betel nut consumption area Taiwan. Besides the definite risk factors of smoking, drinking and betel nut related, the other biomarkers may play significant prognosticators in the HNC outcomes. We concluded that the average BMI is less than 22 kg/m2, the average Hb is low than 12.0 g/dL, the average albumin is low than 3.3 g/dL, the average NLR is low than 3, and the average PLR is more than 170, the surgical complications and mortality will be increased, and the prognosis is poor in HNC patients.Keywords: nutritional, immunological, neutrophil-to-lymphocyte ratio, paltelet-to-lymphocyte ratio.
Procedia PDF Downloads 792439 Analysis of Distance Travelled by Plastic Consumables Used in the First 24 Hours of an Intensive Care Admission: Impacts and Methods of Mitigation
Authors: Aidan N. Smallwood, Celestine R. Weegenaar, Jack N. Evans
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The intensive care unit (ICU) is a particularly resource heavy environment, in terms of staff, drugs and equipment required. Whilst many areas of the hospital are attempting to cut down on plastic use and minimise their impact on the environment, this has proven challenging within the confines of intensive care. Concurrently, as globalization has progressed over recent decades, there has been a tendency towards centralised manufacturing with international distribution networks for products, often covering large distances. In this study, we have modelled the standard consumption of plastic single-use items over the course of the first 24-hours of an average individual patient’s stay in a 12 bed ICU in the United Kingdom (UK). We have identified the country of manufacture and calculated the minimum possible distance travelled by each item from factory to patient. We have assumed direct transport via the shortest possible straight line from country of origin to the UK and have not accounted for transport within either country. Assuming an intubated patient with invasive haemodynamic monitoring and central venous access, there are a total of 52 distincts, largely plastic, disposable products which would reasonably be required in the first 24-hours after admission. Each product type has only been counted once to account for multiple items being shipped as one package. Travel distances from origin were summed to give the total distance combined for all 52 products. The minimum possible total distance travelled from country of origin to the UK for all types of product was 273,353 km, equivalent to 6.82 circumnavigations of the globe, or 71% of the way to the moon. The mean distance travelled was 5,256 km, approximately the distance from London to Mecca. With individual packaging for each item, the total weight of consumed products was 4.121 kg. The CO2 produced shipping these items by air freight would equate to 30.1 kg, however doing the same by sea would produce 0.2 kg CO2. Extrapolating these results to the 211,932 UK annual ICU admissions (2018-2019), even with the underestimates of distance and weight of our assumptions, air freight would account for 6586 tons CO2 emitted annually, approximately 130 times that of sea freight. Given the drive towards cost saving within the UK health service, and the decline of the local manufacturing industry, buying from intercontinental manufacturers is inevitable However, transporting all consumables by sea where feasible would be environmentally beneficial, as well as being less costly than air freight. At present, the NHS supply chain purchases from medical device companies, and there is no freely available information as to the transport mode used to deliver the product to the UK. This must be made available to purchasers in order to give a fuller picture of life cycle impact and allow for informed decision making in this regard.Keywords: CO2, intensive care, plastic, transport
Procedia PDF Downloads 1782438 Application of Co-Flow Jet Concept to Aircraft Lift Increase
Authors: Sai Likitha Siddanathi
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Present project is aimed at increasing the amount of lift produced by typical airfoil. This is achieved by its modification into the co-flow jet structure where a new internal flow is created inside the airfoil from well-designed apertures on its surface. The limit where produced excess lift overcomes the weight of pumping system inserted in airfoil upper portion, and drag force is converted into thrust is discussed in terms of airfoil velocity and angle of attack. Two normal and co-flow jet models are numerically designed and experimental results for both fabricated normal airfoil and CFJ model have been tested in low subsonic wind tunnel. Application has been made to subsonic NACA 652-415 airfoil. Produced lift in CFJ airfoil indicates a maximum value up to a factor of 5 above normal airfoil nearby flow separation ie in relatively weak flow distribution.Keywords: flow Jet, lift coefficient, drag coefficient, airfoil performance
Procedia PDF Downloads 3562437 Study on the Effect of Vitamin D on the Biochemical Parameters in Cyprinus carpio
Authors: Mojdeh Chelemal Dezfoul Nejad, Ali Mohammadzadeh Shobeagar, Mehrzad Mesbah
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This study was conducted in order to characterize the different levels of dietary vitamin D on some of biochemical parameters of Cyprinus carpio. For this purpose, 180 pieces of Cyprinus carpio with an average weight of 20-25 grams were divided into four treatments and each treatment was divided into three replications and treatments were fed at three different doses (1000 IU, 3000 IU, 5000 IU) of vitamin D for 60 days. The fish were fed 3% of their wet b.wt. per day for a 60 days period. Blood samples were obtained from six fish of each tank at the end of experiment. Based on the results significant difference was observed on the mean amount of total protein, urea, glucose and cholesterol between treatments (p < 0.05). But, there was no significant difference in the mean amount of triglyceride and albumin with the different diets designed for this experiment (p > 0.05).Keywords: Cyprinus carpio, vitamin D, biochemical parameters, glucose
Procedia PDF Downloads 3492436 Ultrasonic Studies of Polyurea Elastomer Composites with Inorganic Nanoparticles
Authors: V. Samulionis, J. Banys, A. Sánchez-Ferrer
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Inorganic nanoparticles are used for fabrication of various composites based on polymer materials because they exhibit a good homogeneity and solubility of the composite material. Multifunctional materials based on composites of a polymer containing inorganic nanotubes are expected to have a great impact on industrial applications in the future. An emerging family of such composites are polyurea elastomers with inorganic MoS2 nanotubes or MoSI nanowires. Polyurea elastomers are a new kind of materials with higher performance than polyurethanes. The improvement of mechanical, chemical and thermal properties is due to the presence of hydrogen bonds between the urea motives which can be erased at high temperature softening the elastomeric network. Such materials are the combination of amorphous polymers above glass transition and crosslinkers which keep the chains into a single macromolecule. Polyurea exhibits a phase separated structure with rigid urea domains (hard domains) embedded in a matrix of flexible polymer chains (soft domains). The elastic properties of polyurea can be tuned over a broad range by varying the molecular weight of the components, the relative amount of hard and soft domains, and concentration of nanoparticles. Ultrasonic methods as non-destructive techniques can be used for elastomer composites characterization. In this manner, we have studied the temperature dependencies of the longitudinal ultrasonic velocity and ultrasonic attenuation of these new polyurea elastomers and composites with inorganic nanoparticles. It was shown that in these polyurea elastomers large ultrasonic attenuation peak and corresponding velocity dispersion exists at 10 MHz frequency below room temperature and this behaviour is related to glass transition Tg of the soft segments in the polymer matrix. The relaxation parameters and Tg depend on the segmental molecular weight of the polymer chains between crosslinking points, the nature of the crosslinkers in the network and content of MoS2 nanotubes or MoSI nanowires. The increase of ultrasonic velocity in composites modified by nanoparticles has been observed, showing the reinforcement of the elastomer. In semicrystalline polyurea elastomer matrices, above glass transition, the first order phase transition from quasi-crystalline to the amorphous state has been observed. In this case, the sharp ultrasonic velocity and attenuation anomalies were observed near the transition temperature TC. Ultrasonic attenuation maximum related to glass transition was reduced in quasicrystalline polyureas indicating less influence of soft domains below TC. The first order phase transition in semicrystalline polyurea elastomer samples has large temperature hysteresis (> 10 K). The impact of inorganic MoS2 nanotubes resulted in the decrease of the first order phase transition temperature in semicrystalline composites.Keywords: inorganic nanotubes, polyurea elastomer composites, ultrasonic velocity, ultrasonic attenuation
Procedia PDF Downloads 3012435 Lightweight Sheet Molding Compound Composites by Coating Glass Fiber with Cellulose Nanocrystals
Authors: Amir Asadi, Karim Habib, Robert J. Moon, Kyriaki Kalaitzidou
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There has been considerable interest in cellulose nanomaterials (CN) as polymer and polymer composites reinforcement due to their high specific modulus and strength, low density and toxicity, and accessible hydroxyl side groups that can be readily chemically modified. The focus of this study is making lightweight composites for better fuel efficiency and lower CO2 emission in auto industries with no compromise on mechanical performance using a scalable technique that can be easily integrated in sheet molding compound (SMC) manufacturing lines. Light weighting will be achieved by replacing part of the heavier components, i.e. glass fibers (GF), with a small amount of cellulose nanocrystals (CNC) in short GF/epoxy composites made using SMC. CNC will be introduced as coating of the GF rovings prior to their use in the SMC line. The employed coating method is similar to the fiber sizing technique commonly used and thus it can be easily scaled and integrated to industrial SMC lines. This will be an alternative route to the most techniques that involve dispersing CN in polymer matrix, in which the nanomaterials agglomeration limits the capability for scaling up in an industrial production. We have demonstrated that incorporating CNC as a coating on GF surface by immersing the GF in CNC aqueous suspensions, a simple and scalable technique, increases the interfacial shear strength (IFSS) by ~69% compared to the composites produced by uncoated GF, suggesting an enhancement of stress transfer across the GF/matrix interface. As a result of IFSS enhancement, incorporation of 0.17 wt% CNC in the composite results in increases of ~10% in both elastic modulus and tensile strength, and 40 % and 43 % in flexural modulus and strength respectively. We have also determined that dispersing 1.4 and 2 wt% CNC in the epoxy matrix of short GF/epoxy SMC composites by sonication allows removing 10 wt% GF with no penalty on tensile and flexural properties leading to 7.5% lighter composites. Although sonication is a scalable technique, it is not quite as simple and inexpensive as coating the GF by passing through an aqueous suspension of CNC. In this study, the above findings are integrated to 1) investigate the effect of CNC content on mechanical properties by passing the GF rovings through CNC aqueous suspension with various concentrations (0-5%) and 2) determine the optimum ratio of the added CNC to the removed GF to achieve the maximum possible weight reduction with no cost on mechanical performance of the SMC composites. The results of this study are of industrial relevance, providing a path toward producing high volume lightweight and mechanically enhanced SMC composites using cellulose nanomaterials.Keywords: cellulose nanocrystals, light weight polymer-matrix composites, mechanical properties, sheet molding compound (SMC)
Procedia PDF Downloads 2252434 Diagnostic Delays and Treatment Dilemmas: A Case of Drug-Resistant HIV and Tuberculosis
Authors: Christi Jackson, Chuka Onaga
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Introduction: We report a case of delayed diagnosis of extra-pulmonary INH-mono-resistant Tuberculosis (TB) in a South African patient with drug-resistant HIV. Case Presentation: A 36-year old male was initiated on 1st line (NNRTI-based) anti-retroviral therapy (ART) in September 2009 and switched to 2nd line (PI-based) ART in 2011, according to local guidelines. He was following up at the outpatient wellness unit of a public hospital, where he was diagnosed with Protease Inhibitor resistant HIV in March 2016. He had an HIV viral load (HIVVL) of 737000 copies/mL, CD4-count of 10 cells/µL and presented with complaints of productive cough, weight loss, chronic diarrhoea and a septic buttock wound. Several investigations were done on sputum, stool and pus samples but all were negative for TB. The patient was treated with antibiotics and the cough and the buttock wound improved. He was subsequently started on a 3rd-line ART regimen of Darunavir, Ritonavir, Etravirine, Raltegravir, Tenofovir and Emtricitabine in May 2016. He continued losing weight, became too weak to stand unsupported and started complaining of abdominal pain. Further investigations were done in September 2016, including a urine specimen for Line Probe Assay (LPA), which showed M. tuberculosis sensitive to Rifampicin but resistant to INH. A lymph node biopsy also showed histological confirmation of TB. Management and outcome: He was started on Rifabutin, Pyrazinamide and Ethambutol in September 2016, and Etravirine was discontinued. After 6 months on ART and 2 months on TB treatment, his HIVVL had dropped to 286 copies/mL, CD4 improved to 179 cells/µL and he showed clinical improvement. Pharmacy supply of his individualised drugs was unreliable and presented some challenges to continuity of treatment. He successfully completed his treatment in June 2017 while still maintaining virological suppression. Discussion: Several laboratory-related factors delayed the diagnosis of TB, including the unavailability of urine-lipoarabinomannan (LAM) and urine-GeneXpert (GXP) tests at this facility. Once the diagnosis was made, it presented a treatment dilemma due to the expected drug-drug interactions between his 3rd-line ART regimen and his INH-resistant TB regimen, and specialist input was required. Conclusion: TB is more difficult to diagnose in patients with severe immunosuppression, therefore additional tests like urine-LAM and urine-GXP can be helpful in expediting the diagnosis in these cases. Patients with non-standard drug regimens should always be discussed with a specialist in order to avoid potentially harmful drug-drug interactions.Keywords: drug-resistance, HIV, line probe assay, tuberculosis
Procedia PDF Downloads 1712433 Nutritional and Functional Composition of Prickly Pear Cactus (Opuntia ficus-indica Mill.) Grown in Algeria
Authors: Kamel Cheriet
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In Algeria, Opuntia ficus Indica production is important. This seasonal fruit is a characteristic of arid and semi-arid regions. Taking into account its high content in antioxidants, it has an excellent nutritional value. The aim of this research is the prickly pear morphological and physicochemical characterization study which is widely present in the Arris (Batna, Algeria) area. The results of this experimental study are comparative to those of the same species from other world regions. The whole fruit weight is estimated to reach 63.38 g with a juice ratio of 71.42%, a pH of 5.54, moisture of 89.3% and a brix of 10.4°. The quantitative amount of the phenolic compounds of the fruit revealed contents of 20.65-45.70 mg / 100 g of MF for total polyphenols and 0.519 -0.591 mg / 100 g of MF for the flavonoids.Keywords: functional composition, nutritionals properties, opuntia ficus indica, phenolic compounds
Procedia PDF Downloads 2312432 UV Resistibility of a Carbon Nanofiber Reinforced Polymer Composite
Authors: A. Evcin, N. Çiçek Bezir, R. Duman, N. Duman
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Nowadays, a great concern is placed on the harmfulness of ultraviolet radiation (UVR) which attacks human bodies. Nanocarbon materials, such as carbon nanotubes (CNTs), carbon nanofibers (CNFs) and graphene, have been considered promising alternatives to shielding materials because of their excellent electrical conductivities, very high surface areas and low densities. In the present work, carbon nanofibers have been synthesized from solutions of Polyacrylonitrile (PAN)/ N,N-dimethylformamide (DMF) by electrospinning method. The carbon nanofibers have been stabilized by oxidation at 250 °C for 2 h in air and carbonized at 750 °C for 1 h in H2/N2. We present the fabrication and characterization of transparent and ultraviolet (UV) shielding CNF/polymer composites. The content of CNF filler has been varied from 0.2% to 0.6 % by weight. UV Spectroscopy has been performed to study the effect of composition on the transmittance of polymer composites.Keywords: electrospinning, carbon nanofiber, characterization, composites, nanofiber, ultraviolet radiation
Procedia PDF Downloads 2252431 Model of the Increasing the Capacity of the Train and Railway Track by Using the New Type of Wagon
Authors: Martin Kendra, Jaroslav Mašek, Juraj Čamaj, Martin Búda
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The paper deals with possibilities of increase train capacity by using a new type of railway wagon. In the first part is created a mathematical model to calculate the capacity of the train. The model is based on the main limiting parameters of the train - maximum number of axles per train, the maximum gross weight of the train, the maximum length of train and number of TEUs per one wagon. In the second part is the model applied to four different model trains with different composition of the train set and three different average weights of TEU and a train consisting of a new type of wagons. The result is to identify where the carrying capacity of the original trains is higher, respectively less than a capacity of the train consisting of a new type of wagons.Keywords: loading units, theoretical capacity model, train capacity, wagon for intermodal transport
Procedia PDF Downloads 4972430 Progress Towards Optimizing and Standardizing Fiducial Placement Geometry in Prostate, Renal, and Pancreatic Cancer
Authors: Shiva Naidoo, Kristena Yossef, Grimm Jimm, Mirza Wasique, Eric Kemmerer, Joshua Obuch, Anand Mahadevan
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Background: Fiducial markers effectively enhance tumor target visibility prior to Stereotactic Body Radiation Therapy or Proton therapy. To streamline clinical practice, fiducial placement guidelines from a robotic radiosurgery vendor were examined with the goals of optimizing and standardizing feasible geometries for each treatment indication. Clinical examples of prostate, renal, and pancreatic cases are presented. Methods: Vendor guidelines (Accuray, Sunnyvale, Ca) suggest implantation of 4–6 fiducials at least 20 mm apart, with at least a 15-degree angular difference between fiducials, within 50 mm or less from the target centroid, to ensure that any potential fiducial motion (e.g., from respiration or abdominal/pelvic pressures) will mimic target motion. Also recommended is that all fiducials can be seen in 45-degree oblique views with no overlap to coincide with the robotic radiosurgery imaging planes. For the prostate, a standardized geometry that meets all these objectives is a 2 cm-by-2 cm square in the coronal plane. The transperineal implant of two pairs of preloaded tandem fiducials makes the 2 cm-by-2 cm square geometry clinically feasible. This technique may be applied for renal cancer, except repositioned in a sagittal plane, with the retroperitoneal placement of the fiducials into the tumor. Pancreatic fiducial placement via endoscopic ultrasound (EUS) is technically more challenging, as fiducial placement is operator-dependent, and lesion access may be limited by adjacent vasculature, tumor location, or restricted mobility of the EUS probe in the duodenum. Fluoroscopically assisted fiducial placement during EUS can help ensure fiducial markers are deployed with optimal geometry and visualization. Results: Among the first 22 fiducial cases on a newly installed robotic radiosurgery system, live x-ray images for all nine prostatic cases had excellent fiducial visualization at the treatment console. Renal and pancreatic fiducials were not as clearly visible due to difficult target access and smaller caliber insertion needle/fiducial usage. The geometry of the first prostate case was used to ensure accurate geometric marker placement for the remaining 8 cases. Initially, some of the renal and pancreatic fiducials were closer than the 20 mm recommendation, and interactive feedback with the proceduralists led to subsequent fiducials being too far to the edge of the tumor. Further feedback and discussion of all cases are being used to help guide standardized geometries and achieve ideal fiducial placement. Conclusion: The ideal tradeoffs of fiducial visibility versus the thinnest possible gauge needle to avoid complications needs to be systematically optimized among all patients, particularly in regards to body habitus. Multidisciplinary collaboration among proceduralists and radiation oncologists can lead to improved outcomes.Keywords: fiducial, prostate cancer, renal cancer, pancreatic cancer, radiotherapy
Procedia PDF Downloads 932429 Utilising Unground Oil Palm Ash in Producing Foamed Concrete and Its Implementation as an Interlocking Mortar-Less Block
Authors: Hanizam Awang, Mohammed Zuhear Al-Mulali
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In this study, the possibility of using unground oil palm ash (UOPA) for producing foamed concrete is investigated. The UOPA used in this study is produced by incinerating palm oil biomass at a temperature exceeding 1000ºC. A semi-structural density of 1300kg/m3 was used with filler to binder ratio of 1.5 and preliminary water to binder ratio of 0.45. Cement was replaced by UOPA at replacement levels of 0, 25, 35, 45, 55 and 65% by weight of binder. Properties such as density, compressive strength, drying shrinkage and water absorption were investigated to the age of 90 days. The mix with a 35% of UOPA content was chosen to be used as the base material of a newly designed interlocking, mortar-less block system.Keywords: foamed concrete, oil palm ash, strength, interlocking block
Procedia PDF Downloads 2642428 Construction of Green Aggregates from Waste Processing
Authors: Fahad K. Alqahtani
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Nowadays construction industry is developing means to incorporate waste products in concrete to ensure sustainability. To meet the need of construction industry, a synthetic aggregate was developed using optimized technique called compression moulding press technique. The manufactured aggregate comprises mixture of plastic, waste which acts as binder, together with by-product waste which acts as fillers. The physical properties and microstructures of the inert materials and the manufactured aggregate were examined and compared with the conventional available aggregates. The outcomes suggest that the developed aggregate has potential to be used as substitution of conventional aggregate due to its less weight and water absorption. The microstructure analysis confirmed the efficiency of the manufacturing process where the final product has the same mixture of binder and filler.Keywords: fly ash, plastic waste, quarry fine, red sand, synthetic aggregate
Procedia PDF Downloads 2312427 Effect of Phosphorus Solubilizing Bacteria on Yield and Seed Quality of Camelina (Camelina sativa L.) under Drought Stress
Authors: Muhammad Naeem Chaudhry, Fahim Nawaz, Rana Nauman Shabbir
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New strategies aimed at increasing the resilience of crop plants to the negative effects of climate change represent important research priorities of plant scientists. The use of soil microorganisms to alleviate abiotic stresses like drought has gained particular importance in recent past. A field experiment was planned to investigate the effect of phosphorous solubilizing bacteria on yield and seed quality of Camelina (Camelina sativa L.) under water deficit conditions. The study was conducted at Agronomic Research Farm, University College of Agriculture and Environmental Sciences, The Islamia University Bahawalpur, during 4th week of November, 2013. The available seeds of Camelina sativa were inoculated with two bacterial strains (pseudomonas and Bacillus spp.) and grown under various water stress levels i.e. D0, (four irrigations), D3 (three irrigation), D2 (two irrigations), and D1 (one irrigation). The results revealed that drought stress significantly reduced the plant growth and yield, consequently reducing protein contents and oil concentration in camelina. The exposure to drought stress decreased plant height (16%), plant population (27%), number of fertile branches (41-59%), number of pods per plant (35%) and seed per pod (33%). Drought stress also exerted a negative impact on yield characteristics by reducing the 1000-seed weight (65%), final seed yield (52%), biological yield (22%) and harvest index (39%) of camelina. However, the inoculation of seeds with Pseudomonas and Bacillus spp. promoted the plant growth characterized by increased plant height and enhanced plant population. It was noted that inoculation of seeds with Pseudomonas resulted in the maximum plant population (113.4 cm), primary branches (19 plant-1), and number of pods (664 plant-1), whereas Bacillus inoculation resulted in maximum plant height (113.4 cm), seeds per pod (15.9), 1000-seed weight (1.85 g), and seed yield (3378.8 kg ha-1). Moreover, the inoculation with Bacillus also significantly improved the quality attributes of camelina and gave 3.5% and 2.1% higher oil contents than Pseudomonas and control (no-inoculation), respectively. Similarly, the same strain also resulted in maximum protein contents (33.3%). Our results confirmed the hypothesis that inoculation of seeds with phosphorous solubilizing bacterial strains is an effective, viable and environment-friendly approach to improve yield and quality of camelina under water deficit conditions. However, further studies are suggested to investigate the physiological and molecular processes, stimulated by bacterial strains, for increasing drought tolerance in food crops.Keywords: Camelina, drought stress, phosphate solubilizing bacteria, seed quality
Procedia PDF Downloads 2592426 Kinematical Analysis of Tai Chi Chuan Players during Gait and Balance Test and Implication in Rehabilitation Exercise
Authors: Bijad Alqahtani, Graham Arnold, Weijie Wang
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Background—Tai Chi Chuan (TCC) is a type of traditional Chinese martial art and is considered a benefiting physical fitness. Advanced techniques of motion analysis have been routinely used in the clinical assessment. However, so far, little research has been done on the biomechanical assessment of TCC players in terms of gait and balance using motion analysis. Objectives—The aim of this study was to investigate whether TCC improves the lower limb conditions and balance ability using the state of the art motion analysis technologies, i.e. motion capture system, electromyography and force platform. Methods—Twenty TCC (9 male, 11 female) with age between (42-77) years old and weight (56.2-119 Kg), and eighteen Non-TCC participants (7 male, 11 female), weight (50-110 Kg) with age (43- 78) years old at the matched age as a control group were recruited in this study. Their gait and balance were collected using Vicon Nexus® to obtain the gait parameters, and kinematic parameters of hip, knee, and ankle joints in three planes of both limbs. Participants stood on force platforms to perform a single leg balance test. Then, they were asked to walk along a 10 m walkway at their comfortable speed. Participants performed 5 trials of single-leg balance for the dominant side. Also, the participants performed 3 trials of four square step balance and 10 trials of walking. From the recorded trials, three good ones were analyzed using the Vicon Plug-in-Gait model to obtain gait parameters, e.g. walking speed, cadence, stride length, and joint parameters, e.g. joint angle, force, moments, etc. Result— The temporal-spatial variables of TCC subjects were compared with the Non-TCC subjects, it was found that there was a significant difference (p < 0.05) between the groups. Moreover, it was observed that participants of TCC have significant differences in ankle, hip, and knee joints’ kinematics in the sagittal, coronal, and transverse planes such as ankle angle (19.90±19.54 deg) for TCC while (15.34±6.50 deg) for Non-TCC, and knee angle (14.96±6.40 deg) for TCC while (17.63±5.79 deg) for Non-TCC in the transverse plane. Also, the result showed that there was a significant difference between groups in the single-leg balance test, e.g. maintaining single leg stance time in the TCC participants showed longer duration (20.85±10.53 s) in compared to Non-TCC people group (13.39±8.78 s). While the result showed that there was no significant difference between groups in the four square step balance. Conclusion—Our result showed that there are significant differences between Tai Chi Chuan and Non-Tai Chi Chuan participants in the various aspects of gait analysis and balance test, as a consequence of these findings some of biomechanical parameters such as joints kinematics, gait parameters and single leg stance balance test, the Tai Chi Chuan could improve the lower limb conditions and could reduce a risk of fall for the elderly with ageing.Keywords: gait analysis, kinematics, single leg stance, Tai Chi Chuan
Procedia PDF Downloads 1272425 Efficacy of Ivermectin Agaist Sarcoptes Scabiei Var. Cameli in Libya
Authors: Ahmed Rashed
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Sarcoptic mange is generally recognized as one of the most serious diseases in camels in Libya. It is an extremely pruritic and contagious skin condition caused by Sarcoptes scabiei var cameli. Thirteen camels (camelis dromedaries), showing progressive infection with S.scabiei mites in skin scrapings, were chosen randomly from different affected herds at AL-Assa camel project. Ten camels were treated with ivermectin (22,23-dihydroavermectin B1, Ivomec, Merck) at a dose rate of 0.2 mg./kg.body weight. Scratching and rubbing had completely disappeared in the treated camels one week after the second injection. Two weeks after the second injection motile mites were found on only one camel, and three weeks after the second injection, no motile mites were detected. Motile mites were observed in the three untreated camels up to the end of the trial.Keywords: ivermecti, Sarcoptes scabiei, camels, scrapings
Procedia PDF Downloads 5082424 Gas Metal Arc Welding of Clad Plates API 5L X-60/316L Applying External Magnetic Fields during Welding
Authors: Blanca A. Pichardo, Victor H. Lopez, Melchor Salazar, Rafael Garcia, Alberto Ruiz
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Clad pipes in comparison to plain carbon steel pipes offer the oil and gas industry high corrosion resistance, reduction in economic losses due to pipeline failures and maintenance, lower labor risk, prevent pollution and environmental damage due to hydrocarbons spills caused by deteriorated pipelines. In this context, it is paramount to establish reliable welding procedures to join bimetallic plates or pipes. Thus, the aim of this work is to study the microstructure and mechanical behavior of clad plates welded by the gas metal arc welding (GMAW) process. A clad of 316L stainless steel was deposited onto API 5L X-60 plates by overlay welding with the GMAW process. Welding parameters were, 22.5 V, 271 A, heat input 1,25 kJ/mm, shielding gas 98% Ar + 2% O₂, reverse polarity, torch displacement speed 3.6 mm/s, feed rate 120 mm/s, electrode diameter 1.2 mm and application of an electromagnetic field of 3.5 mT. The overlay welds were subjected to macro-structural and microstructural characterization. After manufacturing the clad plates, a single V groove joint was machined with a 60° bevel and 1 mm root face. GMA welding of the bimetallic plates was performed in four passes with ER316L-Si filler for the root pass and an ER70s-6 electrode for the subsequent welding passes. For joining the clad plates, an electromagnetic field was applied with 2 purposes; to improve the microstructural characteristics and to assist the stability of the electric arc during welding in order to avoid magnetic arc blow. The welds were macro and microstructurally characterized and the mechanical properties were also evaluated. Vickers microhardness (100 g load for 10 s) measurements were made across the welded joints at three levels. The first profile, at the 316L stainless steel cladding, was quite even with a value of approximately 230 HV. The second microhardness profile showed high values in the weld metal, ~400 HV, this was due to the formation of a martensitic microstructure by dilution of the first welding pass with the second. The third profile crossed the third and fourth welding passes and an average value of 240 HV was measured. In the tensile tests, yield strength was between 400 to 450 MPa with a tensile strength of ~512 MPa. In the Charpy impact tests, the results were 86 and 96 J for specimens with the notch in the face and in the root of the weld bead, respectively. The results of the mechanical properties were in the range of the API 5L X-60 base material. The overlap welding process used for cladding is not suitable for large components, however, it guarantees a metallurgical bond, unlike the most commonly used processes such as thermal expansion. For welding bimetallic plates, control of the temperature gradients is key to avoid distortions. Besides, the dissimilar nature of the bimetallic plates gives rise to the formation of a martensitic microstructure during welding.Keywords: clad pipe, dissimilar welding, gas metal arc welding, magnetic fields
Procedia PDF Downloads 1522423 Investigation of Acidizing Corrosion Inhibitors for Mild Steel in Hydrochloric Acid: Theoretical and Experimental Approaches
Authors: Ambrish Singh
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The corrosion inhibition performance of pyran derivatives (AP) on mild steel in 15% HCl was investigated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, weight loss, contact angle, and scanning electron microscopy (SEM) measurements, DFT and molecular dynamic simulation. The adsorption of APs on the surface of mild steel obeyed Langmuir isotherm. The potentiodynamic polarization study confirmed that inhibitors are mixed type with cathodic predominance. Molecular dynamic simulation was applied to search for the most stable configuration and adsorption energies for the interaction of the inhibitors with Fe (110) surface. The theoretical data obtained are, in most cases, in agreement with experimental results.Keywords: acidizing inhibitor, pyran derivatives, DFT, molecular simulation, mild steel, EIS
Procedia PDF Downloads 1972422 Home-Based Care with Follow-Up at Outpatient Unit or Community-Follow-Up Center with/without Food Supplementation and/or Psychosocial Stimulation of Children with Moderate Acute Malnutrition in Bangladesh
Authors: Md Iqbal Hossain, Tahmeed Ahmed, Kenneth H. Brown
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Objective: To assess the effect of community-based follow up, with or without food-supplementation and/or psychosocial stimulation, as an alternative to current hospital-based follow-up of children with moderate-acute-malnutrition (WHZ < -2 to -3) (MAM). Design/methods: The study was conducted at the ICDDR,B Dhaka Hospital and in four urban primary health care centers of Dhaka, Bangladesh during 2005-2007. The efficacy of five different randomly assigned interventions was compared with respect to the rate of completion of follow-up, growth and morbidity in 227 MAM children aged 6-24 months who were initially treated at ICDDR,B for diarrhea and/or other morbidities. The interventions were: 1) Fortnightly follow-up care (FFC) at the ICDDR,B’s outpatient-unit, including growth monitoring, health education, and micro-nutrient supplementation (H-C, n=49). 2) FFC at community follow-up unit (CNFU) [established in the existing urban primary health-care centers close to the residence of the child] but received the same regimen as H-C (C-C, n=53). 3) As per C-C plus cereal-based supplementary food (SF) (C-SF, n=49). The SF packets were distributed on recruitment and at every visit in CNFU [@1 packet/day for 6–11 and 2 packets/day for 12-24 month old children. Each packet contained 20g toasted rice-powder, 10g toasted lentil-powder, 5g molasses, and 3g soy bean oil, to provide a total of ~ 150kcal with 11% energy from protein]. 4) As per C-C plus psychosocial stimulation (PS) (C-PS, n=43). PS consisted of child-stimulation and parental-counseling conducted by trained health workers. 5) As per C-C plus both SF+PS (C-SF+PS, n=33). Results: A total of 227children (48.5% female), with a mean ± SD age of 12.6 ±3.8 months, and WHZ of - 2.53±0.28 enrolled. Baseline characteristics did not differ by treatment group. The rate of spontaneous attendance at scheduled follow-up visits gradually decreased in all groups. Follow-up attendance and gain in weight and length were greater in groups C-SF, C-SF+PS, and C-PS than C-C, and these indicators were observed least in H-C. Children in the H-C group more often suffered from diarrhea (25 % vs. 4-9%) and fever (28% vs. 8-11%) than other groups (p < 0.05). Children who attended at least five of the total six scheduled follow-up visits gained more in weight (median: 0.86 vs. 0.62 kg, p=0.002), length (median: 2.4 vs. 2.0 cm, p=0.009) than those who attended fewer. Conclusions: Community-based service delivery, especially including supplementary food with or without psychosocial stimulation, permits better rehabilitation of children with MAM compared to current hospital outpatients-based care. By scaling the community-based follow-up including food supplementation with or without psychosocial stimulation, it will be possible to rehabilitate a greater number of MAM children in a better way.Keywords: community-based management, moderate acute malnutrition, psychosocial stimulation, supplementary food
Procedia PDF Downloads 4402421 Vibration Control of a Flexible Structure Using MFC Actuator
Authors: Jinsiang Shaw, Jeng-Jie Huang
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Active vibration control is good for low frequency excitation, with advantages of light weight and adaptability. This paper employs a macro-fiber composite (MFC) actuator for vibration suppression in a cantilevered beam due to its higher output force to reject the disturbance. A notch filter with an adaptive tuning algorithm, the leaky filtered-X least mean square algorithm (leaky FXLMS algorithm), is developed and applied to the system. Experimental results show that the controller and MFC actuator was very effective in attenuating the structural vibration. Furthermore, this notch filter controller was compared with the traditional skyhook controller. It was found that its performance was better, with over 88% vibration suppression near the first resonant frequency of the structure.Keywords: macro-fiber composite, notch filter, skyhook controller, vibration suppression
Procedia PDF Downloads 4622420 The Impact of Globalization on the Development of Israel Advanced Changes
Authors: Erez Cohen
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The study examines the socioeconomic impact of development of an advanced industry in Israel. The research method is based on data collected from the Israel Central Bureau of Statistics and from the National Insurance Institute (NII) databases, which provided information that allows to examine the Economic and Social Changes during the 1990s. The study examined the socioeconomic effects of the development of advanced industry in Israel. The research findings indicate that as a result of globalization processes, the weight of traditional industry began to diminish as a result of factory closures and the laying off of workers. These circumstances led to growing unemployment among the weaker groups in Israeli society, detracting from their income and thus increasing inequality among different socioeconomic groups in Israel and enhancement of social disparities.Keywords: globalization, Israeli advanced industry, public policy, socio-economic indicators
Procedia PDF Downloads 1642419 Mesquite (Prosopis juliflora) Pods as a Local Alternative to Feed Poultry
Authors: Abdulrahman Al-Soqeer, Osamah Fahmy
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This research was aimed to investigate the possibility of using Prosopis juliflora pods as a fodder source for poultry. The study have shown that the inclusion of ground Prosopis pods in a broiler diet added some positive effects on broiler performance such as improving carcasses weight and reducing the weights of the inedible parts. The obtained results encourage repeating the experiment with an increased percentage of Prosopis supplementation in the broiler diets, using some treatments on the Prosopis pods to reduce the undesirable effects of the antinutritional factors in the pods and to increase the percentage of the essential amino acids present in the pods (lysine, methionine, arginine, histidine, isoleucine, leucine and phenylealanine) up to the limits recommended for broilers by NRC 1990.Keywords: amino acids, arginine, broilers, lysine, methionine
Procedia PDF Downloads 2392418 The Effect of the Proportion of Carbon on the Corrosion Rate of Carbon-Steel
Authors: Abdulmagid A. Khattabi, Ahmed A. Hablous, Mofied M. Elnemry
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The carbon steel is of one of the most common mineral materials used in engineering and industrial applications in order to have access to the required mechanical properties, especially after the change of carbon ratio, but this may lead to stimulate corrosion. It has been used in models of solids with different carbon ratios such as 0.05% C, 0.2% C, 0.35% C, 0.5% C, and 0.65% C and have been studied using three testing durations which are 4 weeks, 6 weeks, and 8 weeks and among different corrosion environments such as atmosphere, fresh water, and salt water. This research is for the purpose of finding the effect of the carbon content on the corrosion resistance of steels in different corrosion medium by using the weight loss technique as a function of the corrosion resistance. The results that have been obtained through this research shows that a correlation can be made between corrosion rates and steel's carbon content, and the corrosion resistance decreases with the increase in carbon content.Keywords: proportion of carbon in the steel, corrosion rate, erosion, corrosion resistance in carbon-steel
Procedia PDF Downloads 6062417 Investigating the Physical Properties of Polycaprolactone/Eucomis autumnalis Nanocellulose Composite
Authors: Dolly Selikane, Thandi Gumede
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Among the commonly studied organic fillers for polycaprolactone (PCL), cellulose is the most promising. It is available in various particle sizes and sources, providing numerous options for finding a suitable match for PCL matrices. In this study, cellulose was extracted from the leaves of E. autumnalis to create a PCL/nanocellulose composite through melt blending. The prepared nanocellulose was blended with PCL at a weight ratio of 97/3, and the resulting composite was characterized by its thermal and mechanical properties. The results showed that the addition of nanocellulose to PCL improved its mechanical properties, with a maximum increase of 29% in tensile strength and 31% in Young's modulus. The SEM analysis confirmed the successful blending of PCL and nanocellulose. The findings of this study suggest that the nanocellulose from Eucomis autumnalis plant has the potential to improve the mechanical properties of PCL and could be used in biomedical and packaging applications.Keywords: polycaprolactone, medicinal plants, Eucomis autumnalis, nanocellulose, composite
Procedia PDF Downloads 1242416 Study of Metakaolin-Based Geopolymer with Addition of Polymer Admixtures
Authors: Olesia Mikhailova, Pavel Rovnaník
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In the present work, metakaolin-based geopolymer including different polymer admixtures was studied. Different types of commercial polymer admixtures VINNAPAS® and polyethylene glycol of different relative molecular weight were used as polymer admixtures. The main objective of this work is to investigate the influence of different types of admixtures on the properties of metakaolin-based geopolymer mortars considering their different dosage. Mechanical properties, such as flexural and compressive strength were experimentally determined. Also, study of the microstructure of selected specimens by using a scanning electron microscope was performed. The results showed that the specimen with addition of 1.5% of VINNAPAS® 7016 F and 10% of polyethylene glycol 400 achieved maximum mechanical properties.Keywords: geopolymer, mechanical properties, metakaolin, microstructure, polymer admixtures, porosity
Procedia PDF Downloads 2362415 Different Response of Pure Arctic Char Salvelinus alpinus and Hybrid (Salvelinus alpinus vs. Salvelinus fontinalis Mitchill) to Various Hyperoxic Regimes
Authors: V. Stejskal, K. Lundova, R. Sebesta, T. Vanina, S. Roje
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Pure strain of Arctic char (AC) Salvelinus alpinus and hybrid (HB) Salvelinus alpinus vs. Salvelinus fontinalis Mitchill belong to fish, which with great potential for culture in recirculating aquaculture systems (RAS). Aquaculture of these fish currently use flow-through systems (FTS), especially in Nordic countries such as Iceland (biggest producer), Norway, Sweden, and Canada. Four different water saturation regimes included normoxia (NOR), permanent hyperoxia (HYP), intermittent hyperoxia (HYP ± ) and regimes where one day of normoxia was followed by one day of hyperoxia (HYP1/1) were tested during 63 days of experiment in both species in two parallel experiments. Fish were reared in two identical RAS system consisted of 24 plastic round tanks (300 L each), drum filter, biological filter with moving beads and submerged biofilter. The temperature was maintained using flow-through cooler during at level of 13.6 ± 0.8 °C. Different water saturation regimes were achieved by mixing of pure oxygen (O₂) with water in three (one for each hyperoxic regime) mixing tower equipped with flowmeter for regulation of gas inflow. The water in groups HYP, HYP1/1 and HYP± was enriched with oxygen up to saturation of 120-130%. In HYP group was this level kept during whole day. In HYP ± group was hyperoxia kept for daylight phase (08:00-20:00) only and during night time was applied normoxia in this group. The oxygen saturation of 80-90% in NOR group was created using intensive aeration in header tank. The fish were fed with commercial feed to slight excess at 2 h intervals within the light phase of the day. Water quality parameters like pH, temperature and level of oxygen was monitoring three times (7 am, 10 am and 6 pm) per day using handy multimeter. Ammonium, nitrite and nitrate were measured in two day interval using spectrophotometry. Initial body weight (BW) was 40.9 ± 8.7 g and 70.6 ± 14.8 in AC and HB group, respectively. Final survival of AC ranged from 96.3 ± 4.6 (HYP) to 100 ± 0.0% in all other groups without significant differences among these groups. Similarly very high survival was reached in trial with HB with levels from 99.2 ± 1.3 (HYP, HYP1/1 and NOR) to 100 ± 0.0% (HYP ± ). HB fish showed best growth performance in NOR group reached final body weight (BW) 180.4 ± 2.3 g. Fish growth under different hyperoxic regimes was significantly reduced and final BW was 164.4 ± 7.6, 162.1 ± 12.2 and 151.7 ± 6.8 g in groups HY1/1, HYP ± and HYP, respectively. AC showed different preference for hyperoxic regimes as there were no significant difference in BW among NOR, HY1/1 and HYP± group with final values of 72.3 ± 11.3, 68.3 ± 8.4 and 77.1 ± 6.1g. Significantly reduced growth (BW 61.8 ± 6.8 g) was observed in HYP group. It is evident from present study that there are differences between pure bred Arctic char and hybrid in relation to hyperoxic regimes. The study was supported by projects 'CENAKVA' (No. CZ.1.05/2.1.00/01.0024), 'CENAKVA II' (No. LO1205 under the NPU I program), NAZV (QJ1510077) and GAJU (No. 060/2016/Z).Keywords: recirculating aquaculture systems, Salmonidae, hyperoxia, abiotic factors
Procedia PDF Downloads 182