Search results for: high temperature corrosion

Authors: Jae Woong Sull, Sun Ha Jee

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High-density lipoprotein (HDL) cholesterol levels are associated with decreased risk of coronary artery disease. Several genome-wide association studies (GWAS) for HDL cholesterol levels have implicated cholesterol ester transfer protein (CETP) as possibly causal. We tested for the association between single nucleotide polymorphisms (SNPs) in CETP gene and HDL cholesterol levels in Korean population. Subjects were selected from the Korean Metabolic Syndrome Research Initiative study in the Bundang-Gu area. A total of 2,304 individuals from Bundang-Gu were recruited in 2008. Other subjects were selected from the Severance Hospital (N=4,294). SNP rs6499861 in the CETP gene was associated with mean HDL cholesterol levels (effect per allele -2.044 mg/dL, p=7.23×10-7). Subjects with the CG/GG genotype had a 1.46 -fold (range 1.24–1.72-fold) higher risk of having abnormal HDL cholesterol levels (<40 mg/dL) than subjects with the CC genotype. When analyzed by gender, the association of CETP was stronger in women than in men. When analyzed by physical activity behavior, the association with CETP was much stronger in male subjects with low physical activity (OR=1.54, 95% CI: 1.23-1.92, P=0.0001) than in male subjects with high physical activity. This study clearly demonstrates that genetic variants in CETP influence HDL cholesterol levels in Korean adults.

Keywords: CETP, HDL cholesterol, physical activity, polymorphisms

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Authors: N. Manjunatha, K. T. Rangswamy, N. Nagaraju, H. A. Prameela, P. Rudraswamy, M. Krishnareddy

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The identification of virus in cowpea especially potyviruses is confusing. Even though there are several studies on viruses causing diseases in cowpea, difficult to distinguish based on symptoms and serological detection. The differentiation of potyviruses considering as a constraint, the present study is initiated for molecular characterization, host plant resistance and epidemiology of the BCMV infecting cowpea. The etiological agent causing cowpea mosaic was identified as Bean Common Mosaic Virus (BCMV) on the basis of RT-PCR and electron microscopy. An approximately 750bp PCR product corresponding to coat protein (CP) region of the virus and the presence of long flexuous filamentous particles measuring about 952 nm in size typical to genus potyvirus were observed under electron microscope. The characterized virus isolate genome had 10054 nucleotides, excluding the 3’ terminal poly (A) tail. Comparison of polyprotein of the virus with other potyviruses showed similar genome organization with 9 cleavage sites resulted in 10 functional proteins. The pairwise sequence comparison of individual genes, P1 showed most divergent, but CP gene was less divergent at nucleotide and amino acid level. A phylogenetic tree constructed based on multiple sequence alignments of the polyprotein nucleotide and amino acid sequences of cowpea BCMV and potyviruses showed virus is closely related to BCMV-HB. Whereas, Soybean variant of china (KJ807806) and NL1 isolate (AY112735) showed 93.8 % (5’UTR) and 94.9 % (3’UTR) homology respectively with other BCMV isolates. This virus transmitted to different leguminous plant species and produced systemic symptoms under greenhouse conditions. Out of 100 cowpea genotypes screened, three genotypes viz., IC 8966, V 5 and IC 202806 showed immune reaction in both field and greenhouse conditions. Single marker analysis (SMA) was revealed out of 4 SSR markers linked to BCMV resistance, M135 marker explains 28.2 % of phenotypic variation (R2) and Polymorphic information content (PIC) value of these markers was ranged from 0.23 to 0.37. The correlation and regression analysis showed rainfall, and minimum temperature had significant negative impact and strong relationship with aphid population, whereas weak correlation was observed with disease incidence. Path coefficient analysis revealed most of the weather parameters exerted their indirect contributions to the aphid population and disease incidence except minimum temperature. This study helps to identify specific gaps in knowledge for researchers who may wish to further analyse the science behind complex interactions between vector-virus and host in relation to the environment. The resistant genotypes identified are could be effectively used in resistance breeding programme.

Keywords: cowpea, epidemiology, genotypes, virus

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Authors: Ragini Verma, J. Ponmozhi

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The oral cavity is home to a wide variety of microorganisms that lead to various diseases and even oral cancer. Despite advancements in the diagnosis and detection at the initial phase, the situation hasn’t improved much. Saliva-on-a-chip is an innovative point-of-care platform for early diagnosis of oral cancer and other oral diseases in live and dead cells using a microfluidic device with a current perspective. Some of the major challenges, like real-time imaging of the oral cancer microbes, high throughput values, obtaining a high spatiotemporal resolution, etc. were faced by the scientific community. Integrated microfluidics and microscopy provide powerful approaches to studying the dynamics of oral pathology, microbe interaction, and the oral microenvironment. Here we have developed a saliva-on-chip (salivary microbes) device to monitor the effect on oral cancer. Adhesion of cancer-causing F. nucleatum; subsp. Nucleatum and Prevotella intermedia in the device was observed. We also observed a significant reduction in the oral cancer growth rate when mortality and morbidity were induced. These results show that this approach has the potential to transform the oral cancer and early diagnosis study.

Keywords: microfluidic device, oral cancer microbes, early diagnosis, saliva-on-chip

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Authors: Christoph Speer

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Decentralized ventilation systems should combine a small and economical design with high aerodynamic and thermal efficiency. The Counter Flow Heat Recovery Fan (CHRF) provides the ability to meet these requirements by using only one cross flow fan with a large number of blades to generate both airflows and which simultaneously acts as a regenerative counter flow heat exchanger. The successful development of the first laboratory prototype has shown the potential of this ventilation system. Occurring condensate on the surfaces of the fan blades during the cold and dry season can be recovered through the characteristic mode of operation. Hence the CHRF provides the possibility to avoid the need for frost protection and condensate drain. Through the implementation of system-specific solutions for flow balancing and summer bypass the required functionality is assured. The scalability of the CHRF concept allows the use in renovation as well as in new buildings from single-room devices through to systems for office buildings. High aerodynamic and thermal efficiency and the lower number of required mechatronic components should enable a reduction in investment as well as operating costs. The rotor is the key component of the system, the requirements and possible implementation variants are presented.

Keywords: CHRF, counter flow heat recovery fan, decentralized ventilation system, renovation

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Authors: S. Sivakumar, Ashwin Bala, S. Prithviraj, K. Panthala Rajakumaran, R. Pradeep, J. Udhayakumar

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Studies reveal that acetylene gas derived from hydrolysis of calcium carbide has similar properties to that of diesel. However, the self-ignition temperature of acetylene gas is higher than that of diesel. Early investigations reveal that acetylene gas could be used as alternative fuel mode. In the present work, acetylene gas of 31/min were inducted and diesel was injected into the combustion chamber of a single cylinder air cooled diesel engine. It was observed that the higher calorific value of acetylene gas improves the brake thermal efficiency at full load conditions. The CO and HC emissions were higher at part load conditions as compared to conventional diesel. The Nox emission level was higher and smoke emission was lower during dual fuel mode under all operating conditions. It is concluded that dual fuel mode of acetylene gas and diesel improves the brake thermal efficiency and reduces smoke in diesel engine.

Keywords: acetylene gas, diesel engine, Nox emission, CO emission, HC emission

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Authors: M. Kheirandish, S. Borhani

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In this experiment Polystyrene/Zinc-oxide (PS/ZnO) nanocomposite fibers were produced by electrospinning technique using limonene as a green solvent. First, the morphology of electrospun pure polystyrene (PS) and PS/ZnO nanocomposite fibers investigated by SEM. Results showed the PS fiber diameter decreased by increasing concentration of Zinc Oxide nanoparticles (ZnO NPs). Thermo Gravimetric Analysis (TGA) results showed thermal stability of nanocomposites increased by increasing ZnO NPs in PS electrospun fibers. Considering Differential Scanning Calorimeter (DSC) thermograms for electrospun PS fibers indicated that introduction of ZnO NPs into fibers affects the glass transition temperature (Tg) by reducing it. Also, UV protection properties of nanocomposite fibers were increased by increasing ZnO concentration. Evaluating the effect of metal oxide NPs amount on mechanical properties of electrospun layer showed that tensile strength and elasticity modulus of the electrospun layer of PS increased by addition of ZnO NPs. X-ray diffraction (XRD) pattern of nanopcomposite fibers confirmed the presence of NPs in the samples.

Keywords: electrospininng, nanoparticle, polystyrene, ZnO

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Authors: Thi Hai Anh Nguyen, Pantea Aria

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Tiki is one of the leading e-commerce companies in Viet Nam. Since the beginning of 2020, COVID-19 has been spreading around the world. Thanks to this pandemic, the Tiki platform has many strengths and has faced many threats. Customer behaviour was forecasted to change during the COVID-19 pandemic. The aim of the investigation is (1) Identifying factors affecting online consumer behaviour of Tiki in Ho Chi Minh City, Vietnam, (2) Measuring the level of impact of these factors, and (3) Recommendations for Tiki to improve its business strategy for the next stage. This research studies eight factors and collected 378 online surveys for analysis. Using SPSS software identified five factors (product, price, reliability, and web design) positively influencing customer behaviour. COVID-19 factor does not impact significantly Tiki’s customer behaviour. This research conducted some qualitative interviews to understand shopping experiences and customers’ expectations. One of these interviews’ main points is that Tiki’s customers have high trust in the Tiki brand and its high-quality products. Based on the results, the Tiki corporation should secure its core value. Tiki’s employees and logistics systems should be well-trained and optimized to improve customer experiences.

Keywords: COVID-19, e-commerce, impact, pandemic, Vietnam

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Authors: Mohammadjavad Mahdavinejad, Hadi Yazdi

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The greatest influence we have from the world is shaped through the visual form, thus light is an inseparable element in human life. The use of daylight in visual perception and environment readability is an important issue for users. With regard to the hazards of greenhouse gas emissions from fossil fuels, and in line with the attitudes on the reduction of energy consumption, the correct use of daylight results in lower levels of energy consumed by artificial lighting, heating and cooling systems. Windows are usually the starting points for analysis and simulations to achieve visual comfort and energy optimization; therefore, attention should be paid to the orientation of buildings to minimize electrical energy and maximize the use of daylight. In this paper, by using the Design Builder Software, the effect of the orientation of an 18m²(3m*6m) room with 3m height in city of Tehran has been investigated considering the design constraint limitations. In these simulations, the dimensions of the building have been changed with one degree and the window is located on the smaller face (3m*3m) of the building with 80% ratio. The results indicate that the orientation of building has a lot to do with energy efficiency to meet high-performance architecture and planning goals and objectives.

Keywords: daylight, window, orientation, energy consumption, design builder

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Authors: N. Ahmadi, H. Yousefnia, A. Bahrami-Samani

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Chitosan is a natural and biodegradable polysaccharide with special characteristic for application in intracavital therapy. 166Ho-chitosan has been reported for the treatment of hepatocellular carcinoma and RSV with promising results. The aim of this study was to prepare 186/188Re-chitosan for radiosynovectomy purposes and investigate the probability of its leakage from the knee joint. 186/188Re was produced by neutron irradiation of the natural rhenium in a research reactor. Chemical processing was performed to obtain (186/188Re)-NaReO4- according to the IAEA manual. A stock solution of chitosan was prepared by dissolving in 1 % acetic acid aqueous solution (10 mg/mL). 1.5 mL of this stock solution was added to the vial containing the activity and the mixture was stirred for 5 min in the room temperature. The radiochemical purity of the complex was checked by the ITLC method, showing the purity of higher than 98%. Distribution of the radiolabeled complex was determined after intra-articular injection into the knees of rats. Excellent retention was observed in the joint with approximately no activity in the other organs.

Keywords: chitosan, leakage, radiosynovectomy, rhenium

Procedia PDF Downloads 325

Authors: Maya Agarwala

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Objectives: Audit the quality of clinical photographs taken for Orthodontic patients at Queen’s hospital, Romford. Design and setting: All Orthodontic photographs are taken in the Medical Photography Department at Queen’s Hospital. Retrospective audit with data collected between January - March 2023. Gold standard: Institute of Medical Illustrators (IMI) standard 12 photographs: 6 extraoral and 6 intraoral. 100% of patients to have the standard 12 photographs meeting a satisfactory diagnostic quality. Materials and methods: 30 patients randomly selected. All photographs analysed against the IMI gold standard. Results: A total of 360 photographs were analysed. 100% of the photographs had the 12 photographic views. Of which, 93.1% met the gold standard. Of the extraoral photos: 99.4% met the gold standard, 0.6% had incorrect head positioning. Of the intraoral photographs: 87.2% met the gold standard. The most common intraoral errors were: the presence of saliva pooling (7.2%), insufficient soft tissue retraction (3.3%), incomplete occlusal surface visibility (2.2%) and mirror fogging (1.1%). Conclusion: The gold standard was not met, however the overall standard of Orthodontic photographs is high. Further training of the Medical Photography team is needed to improve the quality of photographs. Following the training, the audit will be repeated. High-quality clinical photographs are an important part of clinical record keeping.

Keywords: orthodontics, paediatric, photography, audit

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Authors: M. Yadegari, M. Nourbakhsh, N. Arbabzadeh

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The skeletal system injuries are of major importance. In addition, it is recommended to use materials for hard tissue repair in open or closed fractures. It is important to use complex minerals with a beneficial effect on hard tissue repair, stimulating cell growth in the bone. Materials that could help avoid bone fracture inflammatory reaction and speed up bone fracture repair are of utmost importance in the treatment of bone fractures. Similar to minerals, the inner eggshell membrane consists of carbohydrates, lipids, proteins with the high pH, high calcium absorptive capacity and with faster bone fracture repair ability. In the present radiographic survey, eggshell-derived bone graft substitutes were used for bone defect repair in 8 dog tibia, measuring bone density on the day of implant placement and 30 and 60 days after placement. In fact, the result of this study shows the difference in bone growth and misshapen bones between treatment and control sites. Cell growth was adequate in treatment sites and misshapen bones were less frequent here than in control sites.

Keywords: bone repair, eggshell powder, implant, radiography

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Authors: Stephan Koehler, Thomas Friedli

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Performance measurement has evolved over time from a unidimensional short-term efficiency focused approach into a balanced multidimensional approach. Today, integrated performance measurement frameworks are often used to avoid local optimization and to encourage continuous improvement of an organization. In literature, the multidimensional characteristic of performance measurement is often described by competitive priorities. At the same time, on the highest abstraction level an effectiveness and efficiency dimension of performance measurement can be distinguished. This paper aims at a better understanding of the composition of effectiveness and efficiency and their relation in pharmaceutical quality control labs. The research comprises a lab-specific operationalization of effectiveness and efficiency and examines how the two dimensions are interlinked. The basis for the analysis represents a database of the University of St. Gallen including a divers set of 40 different pharmaceutical quality control labs. The research provides empirical evidence that labs with a high effectiveness also accompany a high efficiency. Lab effectiveness explains 29.5 % of the variance in lab efficiency. In addition, labs with an above median operational excellence performance have a statistically significantly higher lab effectiveness and lab efficiency compared to the below median performing labs.

Keywords: empirical study, operational excellence, performance measurement, pharmaceutical quality control lab

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Authors: Nagini Sabbineni, Rajini T. V. Kanth, B. V. Kiranmayee

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India’s economy primarily depends on agriculture yield growth and their allied agro industry products. The agriculture yield prediction is the toughest task for agricultural departments across the globe. The agriculture yield depends on various factors. Particularly countries like India, majority of agriculture growth depends on rain water, which is highly unpredictable. Agriculture growth depends on different parameters, namely Water, Nitrogen, Weather, Soil characteristics, Crop rotation, Soil moisture, Surface temperature and Rain water etc. In our paper, lot of Explorative Data Analysis is done and various predictive models were designed. Further various regression models like Linear, Multiple Linear, Non-linear models are tested for the effective prediction or the forecast of the agriculture yield for various crops in Andhra Pradesh and Telangana states.

Keywords: agriculture yield growth, agriculture yield prediction, explorative data analysis, predictive models, regression models

Procedia PDF Downloads 295

Authors: H. Golchoobian, M. H. Taheri, S. Saedodin, A. Sarafraz

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This paper investigates the possibility of using three systems of organic Rankine auxiliary power generation, ejector refrigeration and absorption to recover energy from a diesel car. The analysis is done for both urban and suburban driving modes that vary from 60 to 120 km/h. Various refrigerants have also been used for organic Rankine and Ejector refrigeration cycles. The capacity was evaluated by Organic Rankine Cycle (ORC) system in both urban and suburban conditions for cyclopentane and ammonia as refrigerants. Also, for these two driving plans, produced cooling by absorption refrigeration system under variable ambient temperature conditions and in ejector refrigeration system for R123, R134a and R141b refrigerants were investigated.

Keywords: absorption system, diesel engine, ejector refrigeration, energy recovery, organic Rankine cycle

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Authors: Pravin Gaikwad, Prakash Mahanwar

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The main objective of incorporating natural fibers such as Henequen microfibers (NF) into the High-Density Polyethylene (HDPE) polymer matrix is to reduce the cost and to enhance the mechanical as well as other properties. The Henequen microfibers were chopped manually to 5-7mm in length and added into the polymer matrix at the optimized concentration of 8 wt %. In order to facilitate the link between Henequen microfibers (NF) and HDPE matrix, coupling agent such as Glycidoxy (Epoxy) Functional Methoxy Silane (GPTS) at various concentrations from 0.1%, 0.3%, 0.5%, 0.7%, 0.9%, and 1% by weight to the total fibers were added. The tensile strength of the composite increased marginally while % elongation at break of the composites decreased with increase in silane loading by wt %. Tensile modulus and stiffness observed increased at 0.9 wt % GPTS loading. Flexural as well as impact strength of the composite decreased with increase in GPTS loading by weight %. Dielectric strength of the composite also found increased marginally upto 0.5wt % silane loading and thereafter remained constant.

Keywords: Henequen microfibers (NF), polymer composites, HDPE, coupling agent, GPTS

Procedia PDF Downloads 426

Authors: Sujani B. Y. Abeywardena, Srimala Perera, K. M. Nalin De Silva, S. Walpalage

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Surface modifications are vital to accomplish the moisture management property in highly demanded synthetic fabrics. Biomimetic and bio-inspired surface modifications are identified as one of the fascinating areas of research. In this study, nature’s way of cooling elephants’ body temperature using mud bathing was mimicked to create a superior wettable nylon fabric with improved comfortability. For that, bentonite nanoclay was covalently grafted on nylon fabric using silane as a coupling agent. Fourier transform infrared spectra and Scanning electron microscopy images confirmed the successful grafting of nanoclay on nylon. The superior wettability of surface modified nylon was proved by standard protocols. This fabric coating strongly withstands more than 50 cycles of laundry. It is expected that this bio-inspired wettable nylon fabric may break the barrier of using nylon in various hydrophilic textile applications.

Keywords: bentonite nanoclay, biomimetic, covalent modification, nylon fabric, surface, wettability

Procedia PDF Downloads 191

Authors: Balqees A. Al-Thuhli, Ali H. Al-Badi, Khamis Al-Gharbi

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Information technology is changing rapidly and the users’ expectations are also growing. Dealing with these changes in information technology, while satisfying the users’ needs and expectations is a big challenge. IT managers need to explore new mechanisms/strategies to enable them to cope with such challenges. The objectives of this research are to identify the significant challenges that might face IT managers in higher education institutes in the face of the high and ever growing customer expectations and to propose possible solutions to cope with such high-speed changes in information technology. To achieve these objectives, interviews with the IT professionals from different higher education institutes in Oman were conducted. In addition, documentation (printed and online) related to these institutions were studied and an intensive literature review of published work was examined. The findings of this research are expected to give a better understanding of the challenges that might face the IT managers at higher education institutes. This acquired understanding is expected to highlight the importance of being adaptable and fast in keeping up with the ever-growing technological changes. Moreover, adopting different tools and technologies could assist IT managers in developing their organisations’ IT policies and strategies.

Keywords: information technology, rapid change, CIO roles, challenges, IT managers, coping mechanisms, users' expectations

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Authors: Pham Duc Hieu, Do Thi Huong Lan

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The aim of this paper is to investigate the factors affecting the extent of voluntary disclosure by examining the annual reports of 205 industrial and manufacturing companies listing on Ho Chi Minh Stock Exchange (HSX) and Hanoi Stock Exchange (HNX) for the year end of 2012. Those factors include company size, profitability, leverage, state ownership, managerial ownership, and foreign ownership, board independence, role duality and type of external auditors. Evidence from this study suggests two main findings. (1) Companies with high foreign ownership have a high level of voluntary disclosure. (2) The company size is an important factor related to the increased level of voluntary disclosure in annual reports made by Vietnamese listed companies. The larger the company, the higher the information is disclosed. However, no significant associations are found between profitability, leverage, state ownership, managerial ownership, board independence, role duality and type of external auditors as hypothesized in this study.

Keywords: voluntary disclosure, Vietnamese listed companies, voluntary, duality

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Authors: Pedro Llanos, Diego García

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Spaceflight is considered the last frontier in terms of science, technology, and engineering. But it is also the next frontier in terms of human physiology and performance. After more than 200,000 years humans have evolved under earth’s gravity and atmospheric conditions, spaceflight poses environmental stresses for which human physiology is not adapted. Hypoxia, accelerations, and radiation are among such stressors, our research involves suborbital flights aiming to develop effective countermeasures in order to assure sustainable human space presence. The physiologic baseline of spaceflight participants is subject to great variability driven by age, gender, fitness, and metabolic reserve. The objective of the present study is to characterize different physiologic variables in a population of STEM practitioners during an aerobatic flight. Cardiovascular and pulmonary responses were determined in Science Astronaut Candidates (SACs) during unusual attitude aerobatic flight indoctrination. Physiologic data recordings from 20 subjects participating in high-G flight training were analyzed. These recordings were registered by wearable sensor-vest that monitored electrocardiographic tracings (ECGs), signs of dysrhythmias or other electric disturbances during all the flight. The same cardiovascular parameters were also collected approximately 10 min pre-flight, during each high-G/unusual attitude maneuver and 10 min after the flights. The ratio (pre-flight/in-flight/post-flight) of the cardiovascular responses was calculated for comparison of inter-individual differences. The resulting tracings depicting the cardiovascular responses of the subjects were compared against the G-loads (Gs) during the aerobatic flights to analyze cardiovascular variability aspects and fluid/pressure shifts due to the high Gs. In-flight ECG revealed cardiac variability patterns associated with rapid Gs onset in terms of reduced heart rate (HR) and some scattered dysrhythmic patterns (15% premature ventricular contractions-type) that were considered as triggered physiological responses to high-G/unusual attitude training and some were considered as instrument artifact. Variation events were observed in subjects during the +Gz and –Gz maneuvers and these may be due to preload and afterload, sudden shift. Our data reveal that aerobatic flight influenced the breathing rate of the subject, due in part by the various levels of energy expenditure due to the increased use of muscle work during these aerobatic maneuvers. Noteworthy was the high heterogeneity in the different physiological responses among a relatively small group of SACs exposed to similar aerobatic flights with similar Gs exposures. The cardiovascular responses clearly demonstrated that SACs were subjected to significant flight stress. Routine ECG monitoring during high-G/unusual attitude flight training is recommended to capture pathology underlying dangerous dysrhythmias in suborbital flight safety. More research is currently being conducted to further facilitate the development of robust medical screening, medical risk assessment approaches, and suborbital flight training in the context of the evolving commercial human suborbital spaceflight industry. A more mature and integrative medical assessment method is required to understand the physiology state and response variability among highly diverse populations of prospective suborbital flight participants.

Keywords: g force, aerobatic maneuvers, suborbital flight, hypoxia, commercial astronauts

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Authors: Monica Jong, Antonios Banos, Tom Scott, Chris Webster, David Fletcher

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Hydrogen, as a clean alternative to methane, is relatively easy to make, either from water using electrolysis or from methane using steam reformation. However, hydrogen is much trickier to store than methane, and without effective storage, it simply won’t pass muster as a suitable methane substitute. Physical storage of hydrogen is quite inefficient. Storing hydrogen as a compressed gas at pressures up to 900 times atmospheric is volumetrically inefficient and carries safety implications, whilst storing it as a liquid requires costly and constant cryogenic cooling to minus 253°C. This is where DU steps in as a possible solution. Across the periodic table, there are many different metallic elements that will react with hydrogen to form a chemical compound known as a hydride (or metal hydride). From a chemical perspective, the ‘king’ of the hydride forming metals is palladium because it offers the highest hydrogen storage volumetric capacity. However, this material is simply too expensive and scarce to be used in a scaled-up bulk hydrogen storage solution. Depleted Uranium is the second most volumetrically efficient hydride-forming metal after palladium. The UK has accrued a significant amount of DU because of manufacturing nuclear fuel for many decades, and that is currently without real commercial use. Uranium trihydride (UH3) contains three hydrogen atoms for every uranium atom and can chemically store hydrogen at ambient pressure and temperature at more than twice the density of pure liquid hydrogen for the same volume. To release the hydrogen from the hydride, all you do is heat it up. At temperatures above 250°C, the hydride starts to thermally decompose, releasing hydrogen as a gas and leaving the Uranium as a metal again. The reversible nature of this reaction allows the hydride to be formed and unformed again and again, enabling its use as a high-density hydrogen storage material which is already available in large quantities because of its stockpiling as a ‘waste’ by-product. Whilst the tritium storage credentials of Uranium have been rigorously proven at the laboratory scale and at the fusion demonstrator JET for over 30 years, there is a need to prove the concept for depleted uranium hydrogen storage (HyDUS) at scales towards that which is needed to flexibly supply our national power grid with energy. This is exactly the purpose of the HyDUS project, a collaborative venture involving EDF as the interested energy vendor, Urenco as the owner of the waste DU, and the University of Bristol with the UKAEA as the architects of the technology. The team will embark on building and proving the world’s first pilot scale demonstrator of bulk chemical hydrogen storage using depleted Uranium. Within 24 months, the team will attempt to prove both the technical and commercial viability of this technology as a longer duration energy storage solution for the UK. The HyDUS project seeks to enable a true by-product to wonder material story for depleted Uranium, demonstrating that we can think sustainably about unlocking the potential value trapped inside nuclear waste materials.

Keywords: hydrogen, long duration storage, storage, depleted uranium, HyDUS

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Authors: Jelena Filipovic, Milenko Kosutic

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The dynamic way of life has the tendency to simplify and decrease preparing healthy, quick, cheap and safe meals. Spelt pasta is meeting most of these goals. Contrary to bread, pasta can be stored a long time without deterioration in flavour, odour and usability without losing quality. This paper deals with the chemical composition and content of fatty acids in flaxseed and spelt flour. Ratio of essential fatty acids ω-6/ω-3 is also analysed in spelt pasta and pasta with 0%, 10% and 20% flaxseed flour. Gas chromatography with mass spectrometry is used for carrying out a quantitative analysis of flaxseed flour, spelt flour and pasta liposoluble extracts. Flaxseed flour has a better fatty acid profile than spelt flour, with low levels of saturated fat (approximately 9g/100g), high concentration of linolenic acid (57g/100g) and lower content of linoleic acid (16g/100g), as well as superior ω-6/ω-3 ratio that is 1:4. Flaxseed flour in the share of 10% and 20% in spelt pasta positively contributes to the essential fatty acids daily intake recommended by nutritionists and the improvement of ω-6/ω-3 ratio (6,7:1 and 1:1.2). This paper points out that investigated pasta with flaxseed is a new product with improved functional properties due to high level of ω-3 fatty acids and it is acceptable for consumers in regard to sensory properties.

Keywords: flaxseed, spelt, fatty acids, ω-3/ω-6 ratio, pasta

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Authors: Ji Un Shin, Wei Mao, Hyuk Sang Yoo

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Electrospinning is a versatile tool for fabricating nano-structured polymeric materials. Gelatin hydrogels are considered to be a good material for cell cultivation because of high water swellability as well as good biocompatibility. Three-dimensional (3-D) cell cultivation is a desirable method of cell cultivation for preparing tissues and organs because cell-to-cell interactions or cell-to-matrix interactions can be much enhanced through this approach. For this reason, hydrogels were widely employed as tissue scaffolds because they can support cultivating cells and tissue in multi-dimensions. Major disadvantages of hydrogel-based cell cultivation include low mechanical properties, lack of topography, which should be enhanced for successful tissue engineering. Herein we surface-immobilized gelatin on the surface of nanofibrous matrix for 3-D cell cultivation in topographical cues added environments. Electrospun nanofibers were electrospun with injection of poly(caprolactone) through a single nozzle syringe. Electrospun meshes were then chopped up with a high speed grinder to fine powders. This was hydrolyzed in optimized concentration of sodium hydroxide solution from 1 to 6 hours and harvested by centrifugation. The freeze-dried powders were examined by scanning electron microscopy (SEM) for revealing the morphology and fibrilar shaped with a length of ca. 20um was observed. This was subsequently immersed in gelatin solution for surface-coating of gelatin, where the process repeated up to 10 times for obtaining desirable coating of gelatin on the surface. Gelatin-coated nanofibrils showed high waterswellability in comparison to the unmodified nanofibrils, and this enabled good dispersion properties of the modified nanofibrils in aqueous phase. The degree of water-swellability was increased as the coating numbers of gelatin increased, however, it did not any meaning result after 10 times of gelatin coating process. Thus, by adjusting the gelatin coating times, we could successfully control the degree of hydrophilicity and water-swellability of nanofibrils.

Keywords: nano, fiber, cell, tissue

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Authors: M. Varin, A. M. Dubois, R. Gadbois-Langevin, B. Chalghaf

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Good knowledge of the physical environment is essential for an integrated forest planning. This information enables better forecasting of operating costs, determination of cutting volumes, and preservation of ecologically sensitive areas. The use of satellite images in stereoscopic pairs gives the capacity to generate high precision 3D models, which are scale-adapted for harvesting operations. These models could represent an alternative to 3D LiDAR data, thanks to their advantageous cost of acquisition. The objective of the study was to assess the quality of stereo-derived canopy height models (CHM) in comparison to a traditional LiDAR CHM and ground tree-height samples. Two study sites harboring two different forest stand types (broadleaf and conifer) were analyzed using stereo pairs and tri-stereo images from the WorldView-3 satellite to calculate CHM. Acquisition of multispectral images from an Unmanned Aerial Vehicle (UAV) was also realized on a smaller part of the broadleaf study site. Different algorithms using two softwares (PCI Geomatica and Correlator3D) with various spatial resolutions and band selections were tested to select the 3D modeling technique, which offered the best performance when compared with LiDAR. In the conifer study site, the CHM produced with Corelator3D using only the 50-cm resolution panchromatic band was the one with the smallest Root-mean-square deviation (RMSE: 1.31 m). In the broadleaf study site, the tri-stereo model provided slightly better performance, with an RMSE of 1.2 m. The tri-stereo model was also compared to the UAV, which resulted in an RMSE of 1.3 m. At individual tree level, when ground samples were compared to satellite, lidar, and UAV CHM, RMSE were 2.8, 2.0, and 2.0 m, respectively. Advanced analysis was done for all of these cases, and it has been noted that RMSE is reduced when the canopy cover is higher when shadow and slopes are lower and when clouds are distant from the analyzed site.

Keywords: very high spatial resolution, satellite imagery, WorlView-3, canopy height models, CHM, LiDAR, unmanned aerial vehicle, UAV

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Authors: Mirian Graciella Dalla Porta, Humberto Jorge José, Danielle de Bem Luiz, Regina de F. P. M.Moreira

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Similar to most processing industries, fish processing produces large volumes of wastewater, which contains especially organic contaminants, salts and oils dispersed therein. Different processes have been used for the treatment of fishery wastewaters, but the most commonly used are chemical coagulation and flotation. These techniques are well known but sometimes the characteristics of the treated effluent do not comply with legal standards for discharge. Electrocoagulation (EC) is an electrochemical process that can be used to treat wastewaters in terms of both organic matter and nutrient removal. The process is based on the use of sacrificial electrodes such as aluminum, iron or zinc, that are oxidized to produce metal ions that can be used to coagulate and react with organic matter and nutrients in the wastewater. While EC processes are effective to treatment of several types of wastewaters, applications have been limited due to the high energy demands and high current densities. Generally, the for EC process can be performed without additional chemicals or pre-treatment, but the costs should be reduced for EC processes to become more applicable. In this work, we studied the treatment of a real wastewater from fishmeal industry by electrocoagulation process. Removal efficiencies for chemical oxygen demand (COD), total organic carbon (TOC) turbidity, phosphorous and nitrogen concentration were determined as a function of the operating conditions, such as pH, current density and operating time. The optimum operating conditions were determined to be operating time of 10 minutes, current density 100 A.m-2, and initial pH 4.0. COD, TOC, phosphorous concentration, and turbidity removal efficiencies at the optimum operating conditions were higher than 90% for aluminum electrode. Operating costs at the optimum conditions were calculated as US$ 0.37/m3 (US$ 0.038/kg COD) for Al electrode. These results demonstrate that the EC process is a promising technology to remove nutrients from fishery wastewaters, as the process has both a high efficiency of nutrient removal, and low energy requirements.

Keywords: electrocoagulation, fish, food industry, wastewater

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Authors: Minsu Kim, Hae-Chang Cho, Jae Hoon Chung, Inwook Heo, Kang Su Kim

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For safe design of the UHPC flexural members, accurate estimations of their shear strengths are very important. However, since the shear strengths are significantly affected by various factors such as tensile strength of concrete, shear span to depth ratio, volume ratio of steel fiber, and steel fiber factor, the accurate estimations of their shear strengths are very challenging. In this study, therefore, the Adaptive Neuro-Fuzzy System (ANFIS), which has been widely used to solve many complex problems in engineering fields, was introduced to estimate the shear strengths of UHPC flexural members. A total of 32 experimental results has been collected from previous studies for training of the ANFIS algorithm, and the well-trained ANFIS algorithm provided good estimations on the shear strengths of the UHPC test specimens. Acknowledgement: This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT & Future Planning(NRF-2016R1A2B2010277).

Keywords: ultra-high-performance concrete, ANFIS, shear strength, flexural member

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Authors: Farhan Beg, Raymond Moberly

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The Indian subcontinent is facing a massive challenge with regards to energy security in member countries, to provide reliable electricity to facilitate development across various sectors of the economy and consequently achieve the developmental targets. The instability of the current precarious situation is observable in the frequent system failures and blackouts. The deployment of interconnected electricity ‘Supergrid’ designed to carry huge quanta of power across the Indian sub-continent is proposed in this paper. Besides enabling energy security in the subcontinent, it will also provide a platform for Renewable Energy Sources (RES) integration. This paper assesses the need and conditions for a Supergrid deployment and consequently proposes a meshed topology based on Voltage Source High Voltage Direct Current (VSC-HVDC) converters for the Supergrid modeling. Various control schemes for the control of voltage and power are utilized for the regulation of the network parameters. A 3 terminal Multi Terminal Direct Current (MTDC) network is used for the simulations.

Keywords: super grid, wind and solar energy, high voltage direct current, electricity management, load flow analysis

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Authors: Faisal Salah, Z. A. Aziz, K. K. Viswanathan

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In this article, the effects of g-jitter induced and combined with heat and mass transfer by mixed convection of MHD Maxwell fluid in microgravity situation is investigated for a simple system. This system consists of two heated vertical parallel infinite flat plates held at constant but different temperatures and concentrations. By using modified Darcy’s law, the equations governing the flow are modelled. These equations are solved analytically for the induced velocity, temperature and concentration distributions. Many interesting available results in the relevant literature (i.e. Newtonian fluid) is obtained as the special case of the present general analysis. Finally, the graphical results for the velocity profile of the oscillating flow in the channel are presented and discussed for different values of the material constants.

Keywords: g-jitter, heat and mass transfer, mixed convection, Maxwell fluid, porous medium

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Authors: Sezer Kefeli, Sertaç Arslan

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Supercavitation is a pressure dependent process which gives opportunity to eliminate the wetted surface effects on the underwater vehicle due to the differences of viscosity and velocity effects between liquid (freestream) and gas phase. Cavitation process occurs depending on rapid pressure drop or temperature rising in liquid phase. In this paper, pressure based cavitation is investigated due to the fact that is encountered in the underwater world, generally. Basically, this vapor-filled pressure based cavities are unstable and harmful for any underwater vehicle because these cavities (bubbles or voids) lead to intense shock waves while collapsing. On the other hand, supercavitation is a desired and stabilized phenomena than general pressure based cavitation. Supercavitation phenomena offers the idea of minimizing form drag, and thus supercavitating vehicles are revived. When proper circumstances are set up, which are either increasing the operating speed of the underwater vehicle or decreasing the pressure difference between free stream and artificial pressure, the continuity of the supercavitation is obtainable. There are 2 types of supercavitation to obtain stable and continuous supercavitation, and these are called as natural and artificial supercavitation. In order to generate natural supercavitation, various mechanical structures are discovered, which are called as cavitators. In literature, a lot of cavitator types are studied either experimentally or numerically on a CFD platforms with intent to observe natural supercavitation since the 1900s. In this paper, firstly, experimental results are obtained, and trend lines are generated based on supercavitation parameters in terms of cavitation number (), form drag coefficientC_D, dimensionless cavity diameter (d_m/d_c), and length (L_c/d_c). After that, natural cavitation verification studies are carried out for disk and cone shape cavitators. In addition, supercavitation parameters are numerically analyzed at different operating conditions, and CFD results are fitted into trend lines of experimental results. The aims of this paper are to generate one generally accepted drag coefficient equation for disk and cone cavitators at different cavitator half angle and investigation of the supercavitation parameters with respect to cavitation number. Moreover, 165 CFD analysis are performed at different cavitation numbers on FLUENT version 21R2. Five different cavitator types are modeled on SCDM with respect tocavitator’s half angles. After that, CFD database is generated depending on numerical results, and new trend lines are generated based on supercavitation parameters. These trend lines are compared with experimental results. Finally, the generally accepted drag coefficient equation and equations of supercavitation parameters are generated.

Keywords: cavity envelope, CFD, high speed underwater vehicles, supercavitation, supercavitating flows, supercavitation parameters, drag reduction, viscous force elimination, natural cavitation verification

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Authors: Elias Jemal Abdella

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The Blue Nile River is an important shared resource of Ethiopia, Sudan and also, because it is the major contributor of water to the main Nile River, Egypt. Despite the potential benefits of regional cooperation and integrated joint basin management, all three countries continue to pursue unilateral plans for development. Besides, there is great uncertainty about the likely impacts of climate change in water availability for existing as well as proposed irrigation and hydropower projects in the Blue Nile Basin. The main objective of this study is to quantitatively assess the impact of climate change on the hydrological regime of the upper Blue Nile basin, western Ethiopia. Three models were combined, a dynamic Coordinated Regional Climate Downscaling Experiment (CORDEX) regional climate model (RCM) that is used to determine climate projections for the Upper Blue Nile basin for Representative Concentration Pathways (RCPs) 4.5 and 8.5 greenhouse gas emissions scenarios for the period 2021-2050. The outputs generated from multimodel ensemble of four (4) CORDEX-RCMs (i.e., rainfall and temperature) were used as input to a Soil and Water Assessment Tool (SWAT) hydrological model which was setup, calibrated and validated with observed climate and hydrological data. The outputs from the SWAT model (i.e., projections in river flow) were used as input to a Water Evaluation and Planning (WEAP) water resources model which was used to determine the water resources implications of the changes in climate. The WEAP model was set-up to simulate three development scenarios. Current Development scenario was the existing water resource development situation, Medium-term Development scenario was planned water resource development that is expected to be commissioned (i.e. before 2025) and Long-term full Development scenario were all planned water resource development likely to be commissioned (i.e. before 2050). The projected change of mean annual temperature for period (2021 – 2050) in most of the basin are warmer than the baseline (1982 -2005) average in the range of 1 to 1.4oC, implying that an increase in evapotranspiration loss. Subbasins which already distressed from drought may endure to face even greater challenges in the future. Projected mean annual precipitation varies from subbasin to subbasin; in the Eastern, North Eastern and South western highland of the basin a likely increase of mean annual precipitation up to 7% whereas in the western lowland part of the basin mean annual precipitation projected to decrease by 3%. The water use simulation indicates that currently irrigation demand in the basin is 1.29 Bm3y-1 for 122,765 ha of irrigation area. By 2025, with new schemes being developed, irrigation demand is estimated to increase to 2.5 Bm3y-1 for 277,779 ha. By 2050, irrigation demand in the basin is estimated to increase to 3.4 Bm3y-1 for 372,779 ha. The hydropower generation simulation indicates that 98 % of hydroelectricity potential could be produced if all planned dams are constructed.

Keywords: Blue Nile River, climate change, hydropower, SWAT, WEAP

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Authors: Sai Charan Kamana, Harsha Vardhan Nakkina, B.R. Chandavarkar

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In a highly secure and robust key generation process, a key role is played by randomness and random numbers when current real-world cryptosystems are observed. Most of the present-day cryptographic protocols depend upon the Random Number Generators (RNG), Pseudo-Random Number Generator (PRNG). These protocols often use noisy channels such as Disk seek time, CPU temperature, Mouse pointer movement, Fan noise to obtain true random values. Despite being cost-effective, these noisy channels may need additional hardware devices to continuously communicate with them. On the other hand, Hash functions are Pseudo-Random (because of their requirements). So, they are a good replacement for these noisy channels and have low hardware requirements. This paper discusses, some of the key generation methodologies, and their drawbacks. This paper explains how hash functions can be used in key generation, how to combine Key Derivation Functions with hash functions.

Keywords: key derivation, hash based key derivation, password based key derivation, symmetric key derivation

Procedia PDF Downloads 144