Search results for: thermal fatigue

Authors: Tai Yuan Yu, Pei-Jen Wang

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Oil-free turbomachinery is considered one of the critical technologies for future green power generation systems as rotor machinery systems. Oil-free technology allows clean, compact, and maintenance-free working, and gas foil bearings, abbreviated as GFBs, are important for the technology. Since the first applications in the auxiliary power units and air cycle machines in the 1970s, obvious improvement has been created to the computational models for dynamic rotor behavior. However, many technical issues are still poorly understood or remain unsolved, and some of those are thermal management and the pattern of how pressure will be distributed in bearing clearance. This paper presents a three-dimensional, abbreviated as 3D, fluid-structure interaction model of single pad foil bearings and three pad foil bearings to predict bearing working behavior that researchers could compare characteristics of those. The coupling analysis model involves dynamic working characteristics applied to all the gas film and mechanical structures. Therefore, the elastic deformation of foil structure and the hydrodynamic pressure of gas film can both be calculated by a finite element method program. As a result, the temperature distribution pattern could also be iteratively solved by coupling analysis. In conclusion, the working fluid state in a gas film of various pad forms of bearings working characteristic at constant rotational speed for both can be solved for comparisons with the experimental results.

Keywords: fluid-structure interaction, multi-physics simulations, gas foil bearing, oil-free, transient thermo-hydrodynamic

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Authors: Mohammed W. Abdulrahman

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In the thermochemical water splitting process by Cu-Cl cycle, oxygen gas is produced by an endothermic thermolysis process at a temperature of 530^oC. Oxygen production reactor is a three-phase reactor involving cuprous chloride molten salt, copper oxychloride solid reactant and oxygen gas. To perform optimal performance, the oxygen reactor requires accurate control of heat transfer to the molten salt and decomposing solid particles within the thermolysis reactor. In this paper, the scale up analysis of the oxygen reactor that is heated by an internal helical tube is performed from the perspective of heat transfer. A heat balance of the oxygen reactor is investigated to analyze the size of the reactor that provides the required heat input for different rates of hydrogen production. It is found that the helical tube wall and the service side constitute the largest thermal resistances of the oxygen reactor system. In the analysis of this paper, the Cu-Cl cycle is assumed to be heated by two types of nuclear reactor, which are HTGR and CANDU SCWR. It is concluded that using CANDU SCWR requires more heat transfer rate by 3-4 times than that when using HTGR. The effect of the reactor aspect ratio is also studied and it is found that increasing the aspect ratio decreases the number of reactors and the rate of decrease in the number of reactors decreases by increasing the aspect ratio. Comparisons between the results of this study and pervious results of material balances in the oxygen reactor show that the size of the oxygen reactor is dominated by the heat balance rather than the material balance.

Keywords: heat transfer, Cu-Cl cycle, hydrogen production, oxygen, clean energy

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Authors: Matthias Banholzer, Hagen Müller, Michael Pfitzner

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Gas internal combustion engines are widely used as propulsion systems or in power plants to generate heat and electricity. While there are different types of injection methods including the manifold port fuel injection and the direct injection, the latter has more potential to increase the specific power by avoiding air displacement in the intake and to reduce combustion anomalies such as backfire or pre-ignition. During the opening process of the injector, multiple flow regimes occur: subsonic, transonic and supersonic. To cover the wide range of Mach numbers a compressible pressure-based solver is used. While the standard Pressure Implicit with Splitting of Operators (PISO) method is used for the coupling between velocity and pressure, a high-resolution non-oscillatory central scheme established by Kurganov and Tadmor calculates the convective fluxes. A blending function based on the local Mach- and CFL-number switches between the compressible and incompressible regimes of the developed model. As the considered operating points are well above the critical state of the used fluids, the ideal gas assumption is not valid anymore. For the real gas thermodynamics, the models based on the Soave-Redlich-Kwong equation of state were implemented. The caloric properties are corrected using a departure formalism, for the viscosity and the thermal conductivity the empirical correlation of Chung is used. For the injector geometry, the dimensions of a diesel injector were adapted. Simulations were performed using different nozzle and needle geometries and opening curves. It can be clearly seen that there is a significant influence of all three parameters.

Keywords: high pressure gas injection, hybrid solver, hydrogen injection, needle opening process, real-gas thermodynamics

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Authors: L. Mentar, O. Baka, M. R. Khelladi, A. Azizi

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Zinc oxide (ZnO), as a transparent semiconductor with a wide band gap of 3.4 eV and a large exciton binding energy of 60 meV at room temperature, is one of the most promising materials for a wide range of modern applications. With the development of film growth technologies and intense recent interest in nanotechnology, several varieties of ZnO nanostructured materials have been synthesized almost exclusively by thermal evaporation methods, particularly chemical vapor deposition (CVD), which generally require a high growth temperature above 550 °C. In contrast, wet chemistry techniques such as hydrothermal synthesis and electro-deposition are promising alternatives to synthesize ZnO nanostructures, especially at a significantly lower temperature (below 200°C). In this study, the electro-deposition method was used to produce zinc oxide (ZnO) nanostructures on fluorine-doped tin oxide (FTO)-coated conducting glass substrate from chloride bath. We present the influence of KCl concentrations on the electro-deposition process, morphological, structural and optical properties of ZnO nanostructures. The potentials of electro-deposition of ZnO were determined using the cyclic voltammetry. From the Mott-Schottky measurements, the flat-band potential and the donor density for the ZnO nanostructure are determined. Field emission scanning electron microscopy (FESEM) images showed different sizes and morphologies of the nanostructures which depends on the concentrations of Cl-. Very netted hexagonal grains are observed for the nanostructures deposited at 0.1M of KCl. X-ray diffraction (XRD) study confirms the Wurtzite phase of the ZnO nanostructures with a preferred oriented along (002) plane normal to the substrate surface. UV-Visible spectra showed a significant optical transmission (~80%), which decreased with low Cl-1 concentrations. The energy band gap values have been estimated to be between 3.52 and 3.80 eV.

Keywords: Cl-, electro-deposition, FESEM, Mott-Schottky, XRD, ZnO

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Authors: R. Charoen, S. Tipkanon, W. Savedboworn, N. Phonsatta, A. Panya

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Rice bran protein hydrolysates (RBPH) were prepared from defatted rice bran of two different Thai rice cultivars (Plai-Ngahm-Prachinburi; PNP and Khao Dok Mali 105; KDM105) using an enzymatic method. This research aimed to optimize enzyme-assisted protein extraction. In addition, the functional properties of RBPH and their stabilities to environmental stresses including pH (3 to 8), ionic strength (0 mM to 500 mM) and the thermal treatment (30 °C to 90 °C) were investigated. Results showed that enzymatic process for protein extraction of defatted rice bran was as follows: enzyme concentration 0.075 g/ 5 g of protein, extraction temperature 50 °C and extraction time 4 h. The obtained protein hydrolysate powders had a degree of hydrolysis (%) of 21.05% in PNP and 19.92% in KDM105. The solubility of protein hydrolysates at pH 4-6 was ranged from 27.28-38.57% and 27.60-43.00% in PNP and KDM105, respectively. In general, antioxidant activities indicated by total phenolic content, FRAP, ferrous ion-chelating (FIC), and 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) of KDM105 had higher than PNP. In terms of functional properties, the emulsifying activity index (EAI) was was 8.78 m²/g protein in KDM105, whereas PNP was 5.05 m²/g protein. The foaming capacity at 5 minutes (%) was 47.33 and 52.98 in PNP and KDM105, respectively. Glutamine, Alanine, Valine, and Leucine are the major amino acid in protein hydrolysates where the total amino acid of KDM105 gave higher than PNP. Furthermore, we investigated environmental stresses on the stability of 5% oil in water emulsion (5% oil, 10 mM citrate buffer) stabilized by RBPH (3.5%). The droplet diameter of emulsion stabilized by KDM105 was smaller (d < 250 nm) than produced by PNP. For environmental stresses, RBPH stabilized emulsions were stable at pH around 3 and 5-6, at high salt (< 400 mM, pH 7) and at temperatures range between 30-50°C.

Keywords: functional properties, oil in water emulsion, protein hydrolysates, rice bran protein

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Authors: Adeshina Fadeyibi

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Application of pure thermoplastic film in food packaging is greatly limited because of its poor service performance, often enhanced by the addition of organic or inorganic particles in the range of 1–100 nm. Thus, this study was conducted to develop cassava starch zinc-nanocomposite films for applications in food packaging. Three blending ratios of 1000 g cassava starch, 45–55 % (w/w) glycerol and 0–2 % (w/w) zinc nanoparticles were formulated, mixed and mechanically homogenized to form the nanocomposite. Thermoplastic were prepared, from a dispersed mixture of 24 g of the nanocomposite and 600 ml of distilled water, and heated to 90oC for 30 minutes. Plastic molds of 350 ×180 mm dimension and 8, 10 and 12 mm depths were used for film casting and drying at 60oC and 80 % RH for 24 hour. The average thicknesses of the dried films were found to be 15, 16 and 17 µm. The films were characterized based on their barrier, thermal, mechanical and structural properties. The results show that the oxygen and water vapor barrier properties increased with glycerol concentration and decreased with thickness; but the full width at half maximum (FWHM) and d- spacing increased with thickness. The higher degree of d- spacing obtained is a consequence of higher polymer intercalation and exfoliation. Also, only 2 % weight degradation was observed when the films were exposed to temperature between 30–60oC; indicating that they are thermally stable and can be used for packaging applications in the tropics. The mechanical properties of the film were higher than that of the pure thermoplastic but comparable with the LDPE films. The information on the characterized attributes and optimization of the cassava starch zinc-nanocomposite films justifies their alternative application to pure thermoplastic and conventional films for food packaging.

Keywords: synthesis, characterization, casaava Starch, nanocomposite film, packaging

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Authors: Joanne DiFrancisco-Donoghue, Seth E. Jenny, Peter C. Douris, Sophia Ahmad, Kyle Yuen, Hillary Gan, Kenney Abraham, Amber Sousa

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Background: Guidelines for the maintenance of health of esports players and the cognitive changes that accompany competitive gaming are understudied. Executive functioning is an important cognitive skill for an esports player. The relationship between executive functions and physical exercise has been well established. However, the effects of prolonged sitting regardless of physical activity level have not been established. Prolonged uninterrupted sitting reduces cerebral blood flow. Reduced cerebral blood flow is associated with lower cognitive function and fatigue. This decrease in cerebral blood flow has been shown to be offset by frequent and short walking breaks. These short breaks can be as little as 2 minutes at the 30-minute mark and 6 minutes following 60 minutes of prolonged sitting. The rationale is the increase in blood flow and the positive effects this has on metabolic responses. The primary purpose of this study was to evaluate executive function changes following 6-minute bouts of walking and complete rest mid-session, compared to no break, during prolonged gameplay in competitive first-person shooter (FPS) esports players. Methods: This study was conducted virtually due to the Covid-19 pandemic and was approved by the New York Institute of Technology IRB. Twelve competitive FPS participants signed written consent to participate in this randomized pilot study. All participants held a gold ranking or higher. Participants were asked to play for 2 hours on three separate days. Outcome measures to test executive function included the Color Stroop and the Tower of London tests which were administered online each day prior to gaming and at the completion of gaming. All participants completed the tests prior to testing for familiarization. One day of testing consisted of a 6-minute walk break after 60-75 minutes of play. The Rate of Perceived Exertion (RPE) was recorded. The participant continued to play for another 60-75 minutes and completed the tests again. Another day the participants repeated the same methods replacing the 6-minute walk with lying down and resting for 6 minutes. On the last day, the participant played continuously with no break for 2 hours and repeated the outcome tests pre and post-play. A Latin square was used to randomize the treatment order. Results: Using descriptive statistics, the largest change in mean reaction time incorrect congruent pre to post play was seen following the 6-minute walk (662.0 (609.6) ms pre to 602.8 (539.2) ms post), followed by the 6-minute rest group (681.7(618.1) ms pre to 666.3 (607.9) ms post), and with minimal change in the continuous group (594.0(534.1) ms pre to 589.6(552.9) ms post). The mean solution time was fastest in the resting condition (7774.6(6302.8)ms), followed by the walk condition (7929.4 (5992.8)ms), with the continuous condition being slowest (9337.3(7228.7)ms). the continuous group 9337.3(7228.7) ms; 7929.4 (5992.8 ) ms 774.6(6302.8) ms. Conclusion: Short walking breaks improve blood flow and reduce the risk of venous thromboembolism during prolonged sitting. This pilot study demonstrated that a low intensity 6 -minute walk break, following 60 minutes of play, may also improve executive function in FPS gamers.

Keywords: executive function, FPS, physical activity, prolonged sitting

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Authors: Oya A. Urucu, Aslı B. Çiğil, Hatice Birtane, Ece K. Yetimoğlu, Memet Vezir Kahraman

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Chlorpyrifos is an organophosphorus pesticide which can be found in environmental water samples. The efficiency and reuse of a molecularly imprinted polymer (chlorpyrifos - MIP) were investigated for the selective removal of chlorpyrifos residues. MIP was prepared with UV curing thiol-ene polymerization technology by using multifunctional thiol and ene monomers. The thiol-ene curing reaction is a radical induced process, however unlike other photoinitiated polymerization processes, this polymerization process is a free-radical reaction that proceeds by a step-growth mechanism, involving two main steps; a free-radical addition followed by a chain transfer reaction. It assures a very rapidly formation of a uniform crosslinked network with low shrinkage, reduced oxygen inhibition during curing and excellent adhesion. In this study, thiol-ene based UV-curable polymeric materials were prepared by mixing pentaerythritol tetrakis(3-mercaptopropionate), glyoxal bis diallyl acetal, polyethylene glycol diacrylate (PEGDA) and photoinitiator. Chlorpyrifos was added at a definite ratio to the prepared formulation. Chemical structure and thermal properties were characterized by FTIR and thermogravimetric analysis (TGA), respectively. The pesticide analysis was performed by gas chromatography-mass spectrometry (GC-MS). The influences of some analytical parameters such as pH, sample volume, amounts of analyte concentration were studied for the quantitative recoveries of the analyte. The proposed MIP method was applied to the determination of chlorpyrifos in river and tap water samples. The use of the MIP provided a selective and easy solution for removing chlorpyrifos from the water.

Keywords: molecularly imprinted polymers, selective removal, thilol-ene, uv-curable polymer

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Authors: Soukaina Ounss, Hamid Mounir, Abdellatif El Marjani

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Sandwich materials with composite reinforced skins are mostly required in advanced construction applications with a view to ensure resistant structures. Their lightweight, their high flexural stiffness and their optimal thermal insulation make them a suitable solution to obtain efficient structures with performing rigidity and optimal energy safety. In this paper, the mechanical behavior of a sandwich beam with composite skins reinforced by unidirectional carbon fibers is investigated numerically through analyzing the impact of reinforcements specifications on the longitudinal elastic modulus in order to select the adequate sandwich configuration that has an interesting rigidity and an accurate convergence to the analytical approach which is proposed to verify performed numerical simulations. Therefore, concerned study starts by testing flexion performances of skins with various fibers orientations and volume fractions to determine those to use in sandwich beam. For that, the combination of a reinforcement inclination of 30° and a volume ratio of 60% is selected with the one with 60° of fibers orientation and 40% of volume fraction, this last guarantees to chosen skins an important rigidity with an optimal fibers concentration and a great enhance in convergence to analytical results in the sandwich model for the reason of the crucial core role as transverse shear absorber. Thus, a resistant sandwich beam is elaborated from a face-sheet constituted from two layers of previous skins with fibers oriented in 60° and an epoxy core; concerned beam has a longitudinal elastic modulus of 54 Gpa (gigapascal) that equals to the analytical value by a negligible error of 2%.

Keywords: fibers orientation, fibers volume ratio, longitudinal elastic modulus, sandwich beam

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Authors: O. S. Ebrahim, K. O. Shawky, M. O. S. Ebrahim, P. K. Jain

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Induction Motor (IM) driving pump is the main consumer of electricity in a typical fluid transportation system (FTS). It was illustrated that changing the connection of the stator windings from delta to star at no load could achieve noticeable active and reactive energy savings. This paper proposes a supervisory hysteresis liquid-level control with three-state energy saving mode (ESM) for IM in FTS including storage tank. The IM pump drive comprises modified star/delta switch and hydromantic coupler. Three-state ESM is defined, along with the normal running, and named analog to computer ESMs as follows: Sleeping mode in which the motor runs at no load with delta stator connection, hibernate mode in which the motor runs at no load with a star connection, and motor shutdown is the third energy saver mode. A logic flow-chart is synthesized to select the motor state at no-load for best energetic cost reduction, considering the motor thermal capacity used. An artificial neural network (ANN) state estimator, based on the recurrent architecture, is constructed and learned in order to provide fault-tolerant capability for the supervisory controller. Sequential test of Wald is used for sensor fault detection. Theoretical analysis, preliminary experimental testing and, computer simulations are performed to show the effectiveness of the proposed control in terms of reliability, power quality and energy/coenergy cost reduction with the suggestion of power factor correction.

Keywords: ANN, ESM, IM, star/delta switch, supervisory control, FT, reliability, power quality

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Authors: Marco Frieslaar, Bing Chu, Eric Rogers

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Stroke is a devastating illness that is the second biggest cause of death in the world (after heart disease). Where it does not kill, it leaves survivors with debilitating sensory and physical impairments that not only seriously harm their quality of life, but also cause a high incidence of severe depression. It is widely accepted that early intervention is essential for recovery, but current rehabilitation techniques largely favor hospital-based therapies which have restricted access, expensive and specialist equipment and tend to side-step the emotional challenges. In addition, there is insufficient funding available to provide the long-term assistance that is required. As a consequence, recovery rates are poor. The relatively unexplored solution is to develop therapies that can be harnessed in the home and are formulated from technologies that already exist in everyday life. This would empower individuals to take control of their own improvement and provide choice in terms of when and where they feel best able to undertake their own healing. This research seeks to identify how effective post-stroke, rehabilitation therapy can be applied to upper limb mobility, within the physical context of a home rather than a hospital. This is being achieved through the design and construction of an automation scheme, based on iterative learning control and the Riener muscle model, that has the ability to adapt to the user and react to their level of fatigue and provide tangible physical recovery. It utilizes a SMART Phone and laptop to construct an iterative learning control (ILC) system, that monitors upper arm movement in three dimensions, as a series of exercises are undertaken. The equipment generates functional electrical stimulation to assist in muscle activation and thus improve directional accuracy. In addition, it monitors speed, accuracy, areas of motion weakness and similar parameters to create a performance index that can be compared over time and extrapolated to establish an independent and objective assessment scheme, plus an approximate estimation of predicted final outcome. To further extend its assessment capabilities, nerve conduction velocity readings are taken by the software, between the shoulder and hand muscles. This is utilized to measure the speed of response of neuron signal transfer along the arm and over time, an online indication of regeneration levels can be obtained. This will prove whether or not sufficient training intensity is being achieved even before perceivable movement dexterity is observed. The device also provides the option to connect to other users, via the internet, so that the patient can avoid feelings of isolation and can undertake movement exercises together with others in a similar position. This should create benefits not only for the encouragement of rehabilitation participation, but also an emotional support network potential. It is intended that this approach will extend the availability of stroke recovery options, enable ease of access at a low cost, reduce susceptibility to depression and through these endeavors, enhance the overall recovery success rate.

Keywords: home-based therapy, iterative learning control, Riener muscle model, SMART phone, stroke rehabilitation

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Authors: Ipek Gunay, Efe B. Orman, Metin Ozer, Bekir Salih, Ali R. Ozkaya

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Phthalocyanines with macrocyclic ring containing at least three heteroatoms have nine or more membered structures. Metal-free phthalocyanines react with metal salts to obtain chelate complexes. This is one of the most important features of metal-free phthalocyanine as ligand structure. Although phthalocyanines have very similar properties with porphyrins, they have some advantages such as lower cost, easy to prepare, and chemical and thermal stability. It’s known that Pc compounds have shown one-electron metal-and/or ligand-based reversible or quasi-reversible reduction and oxidation processes. The redox properties of phthalocyanines are critically related to the desirable properties of these compounds in their technological applications. Thus, Pc complexes have also been receiving increasing interest in the area of fuel cells due to their high electrocatalytic activity in dioxygen reduction and fuel cell applications. In this study, novel phthalocyanine complexes coordinated with Fe(II) and Co (II) to be used as catalyst were synthesized. Aiming this goal, a new nitrile ligand was synthesized starting from 4-hydroxy-3,5-dimethoxy benzyl alcohol and 4-nitrophthalonitrile in the presence of K2CO3 as catalyst. After the isolation of the new type of nitrile and metal complexes, the characterization of mentioned compounds was achieved by IR, H-NMR and UV-vis methods. In addition, the electrochemical behaviour of Pc complexes was identified by cyclic voltammetry, square wave voltammetry and in situ spectroelectrochemical measurements. Furthermore, the catalytic performances of Pc complexes for oxygen reduction were tested by dynamic voltammetry measurements, carried out by the combined system of rotating ring-disk electrode and potentiostat, in a medium similar to fuel-cell working conditions.

Keywords: phthalocyanine, electrocatalysis, electrochemistry, in-situ spectroelectrochemistry

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Authors: Malik Abid Hussain Khokhar, Muhammad Adnan Tahir, Hisham Bin Hafeez Awan

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Continuous environmental determinism and climatic change in the entire globe due to increasing land surface temperature (LST) has become a vital phenomenon nowadays. LST is accelerating because of increasing greenhouse gases in the environment which results of melting down ice caps, ice sheets and glaciers. It has not only worse effects on vegetation and water bodies of the region but has also severe impacts on monsoon areas in the form of capricious rainfall and monsoon failure extensive precipitation. Environment can be monitored with the help of various geographic information systems (GIS) based algorithms i.e. SC (Single), DA (Dual Angle), Mao, Sobrino and SW (Split Window). Estimation of LST is very much possible from digital image processing of satellite imagery. This paper will encompass extraction of LST of Abbottabad using SW technique of GIS and Remote Sensing over last ten years by means of Landsat 7 ETM+ (Environmental Thematic Mapper) and Landsat 8 vide their Thermal Infrared (TIR Sensor) and Optical Land Imager (OLI sensor less Landsat 7 ETM+) having 100 m TIR resolution and 30 m Spectral Resolutions. These sensors have two TIR bands each; their emissivity and spectral radiance will be used as input statistics in SW algorithm for LST extraction. Emissivity will be derived from Normalized Difference Vegetation Index (NDVI) threshold methods using 2-5 bands of OLI with the help of e-cognition software, and spectral radiance will be extracted TIR Bands (Band 10-11 and Band 6 of Landsat 7 ETM+). Accuracy of results will be evaluated by weather data as well. The successive research will have a significant role for all tires of governing bodies related to climate change departments.

Keywords: environment, Landsat 8, SW Algorithm, TIR

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Authors: Junyu Chen, Peng Xu

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In the context of global efforts to enhance building energy efficiency, accurate thermal load forecasting is crucial for both device sizing and predictive control. Variable Refrigerant Flow (VRF) systems are widely used in buildings around the world, yet VRF zonal load prediction has received limited attention. Due to differences between VRF zones in building-level prediction methods, zone-level load forecasting could significantly enhance accuracy. Given that modern VRF systems generate high-quality data, this paper introduces transfer learning to leverage this data and further improve prediction performance. This framework also addresses the challenge of predicting load for building zones with no historical data, offering greater accuracy and usability compared to pure white-box models. The study first establishes an initial variable set of VRF zonal building loads and generates a foundational white-box database using EnergyPlus. Key variables for VRF zonal loads are identified using methods including SRRC, PRCC, and Random Forest. XGBoost and LSTM are employed to generate pre-trained black-box models based on the white-box database. Finally, real-world data is incorporated into the pre-trained model using transfer learning to enhance its performance in operational buildings. In this paper, zone-level load prediction was integrated with transfer learning, and a framework was proposed to improve the accuracy and applicability of VRF zonal load prediction.

Keywords: zonal load prediction, variable refrigerant flow (VRF) system, transfer learning, energyplus

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Authors: Pradeep Lamichhane

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Plasma-assisted nitrogen fixation is a process by which atomic nitrogen generated by plasma is converted into ammonia (NH₃) or related nitrogenous compounds. Nitrogen fixation is essential to plant because fixed inorganic nitrogen compounds are required to them for the biosynthesis of all nitrogen-containing organic compounds, such as amino acids and proteins, nucleoside triphosphates and nucleic acid. Most of our atmosphere is composed of nitrogen; however, the plant cannot absorb it directly from the air ambient. As a portion of the nitrogen cycle, nitrogen fixation fundamental for agriculture and the manufacture of fertilizer. In this study, plasma-assisted nitrogen fixation was performed by exposing a non-thermal atmospheric pressure nitrogen plasma generated a sinusoidal power supply (with an applied voltage of 10 kV and frequency of 33 kHz) on a water surface. Besides this, UV excitation of water molecules at the water interface was also done in order to disassociate water. Hydrogen and hydroxyl radical obtained from this UV photolysis electrochemically combine with nitrogen atom obtained from plasma. As a result of this, nitrogen fixation on plasma-activated water (PAW) significantly enhanced. The amount of nitrogen-based products like NOₓ and ammonia (NH₃) synthesized by this combined process of UV and plasma are 1.4 and 2.8 times higher than those obtained by plasma alone. In every 48 hours, 20 ml of plasma-activated water (pH≈3.15) for 10 minutes with moderate concentrations of NOₓ, NH₃ and hydrogen peroxide (H₂O₂) was irrigated on each corn plant (Zea Mays). It was found that the PAW has shown a significant impact on seeds germination rate and improved seedling growth. The result obtained from this experiment suggested that crop yield could increase in a short duration. In the future, this experiment could open boundless opportunities in plasma agriculture to mobilize nitrogen because nitrite, nitrate, and ammonia are more suitable for plant uptake.

Keywords: plasma-assisted nitrogen fixation, nitrogen plasma, UV excitation of water, ammonia synthesis

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Authors: Siva Kumar Bathina, Sudheer Siddapureddy

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Fires accident becomes even worse when the hazardous equipment like reactors or radioactive waste packages are engulfed in fire. In this work, large-eddy numerical fire simulations are performed using fire dynamic simulator to predict the thermal behavior of such bodies engulfed in hydrocarbon pool fires. A radiatively dominated 0.3 m circular burner with n-heptane as the fuel is considered in this work. The fire numerical simulation results without anybody inside the fire are validated with the reported experimental data. The comparison is in good agreement for different flame properties like predicted mass burning rate, flame height, time-averaged center-line temperature, time-averaged center-line velocity, puffing frequency, the irradiance at the surroundings, and the radiative heat feedback to the pool surface. Cask of different sizes is simulated with SS304L material. The results are independent of the material of the cask simulated as the adiabatic surface temperature concept is employed in this study. It is observed that the mass burning rate increases with the blockage ratio (3% ≤ B ≤ 32%). However, the change in this increment is reduced at higher blockage ratios (B > 14%). This is because the radiative heat feedback to the fuel surface is not only from the flame but also from the cask volume. As B increases, the volume of the cask increases and thereby increases the radiative contribution to the fuel surface. The radiative heat feedback in the case of the cask engulfed in the fire is increased by 2.5% to 31% compared to the fire without cask.

Keywords: adiabatic surface temperature, fire accidents, fire dynamic simulator, radiative heat feedback

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Authors: Sreeparna Majee, G. C. Shit

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A study on targeted drug delivery is carried out in an unsteady flow of blood infused with magnetic NPs (nanoparticles) with an aim to understand the flow pattern and nanoparticle aggregation in a diseased arterial segment having stenosis. The magnetic NPs are supervised by the magnetic field which is significant for therapeutic treatment of arterial diseases, tumor and cancer cells and removing blood clots. Coupled thermal energy have also been analyzed by considering dissipation of energy because of the application of the magnetic field and the viscosity of blood. Simulation technique used to solve the mathematical model is vorticity-stream function formulations in the diseased artery. An elevation in SLP (Specific loss power) is noted in the aortic bloodstream when the agglomeration of nanoparticles is higher. This phenomenon has potential application in the treatment of hyperthermia. The study focuses on the lowering of WSS (Wall Shear Stress) with increasing particle concentration at the downstream of the stenosis which depicts the vigorous flow circulation zone. These low shear stress regions prolong the residing time of the nanoparticles carrying drugs which soaks up the LDL (Low Density Lipoprotein) deposition. Moreover, an increase in NP concentration enhances the Nusselt number which marks the increase of heat transfer from the arterial wall to the surrounding tissues to destroy tumor and cancer cells without affecting the healthy cells. The results have a significant influence in the study of medicine, to treat arterial diseases such as atherosclerosis without the need for surgery which can minimize the expenditures on cardiovascular treatments.

Keywords: magnetic nanoparticles, blood flow, atherosclerosis, hyperthermia

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Authors: Huiqiang Yang, Domingo Santana

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This paper proposes a novel configuration which introduces a natural draft dry cooling tower system in a molten salt power tower. A three-dimensional numerical modeling was developed based on the novel configuration. A plan of building 20 new concentrating solar power plants has been announced by Chinese government in September 2016, and among these 20 new plants, most of them are located in regions with long winter and harsh winter climate. The innovative configuration proposed includes an external receiver concrete tower at the center, a natural draft dry cooling tower which is surrounding the external receiver concrete tower and whose shell is fixed on the external receiver concrete tower, and a power block (including a steam generation system, a steam turbine system and hot/cold molten salt tanks, and water treatment systems) is covered by the roof of the natural draft dry cooling tower. Heat exchanger bundles are vertically installed at the furthest edge of the power block. In such a way, all power block equipment operates under suitable environmental conditions through whole year operation. The monthly performance of the novel configuration is simulated as compared to a standard one. The results show that the novel configuration is much more efficient in each separate month in a typical meteorological year. Moreover, all systems inside the power block have less thermal losses at low ambient temperatures, especially in harsh winter climate. It is also worthwhile mentioning that a photovoltaic power plant can be installed on the roof of the cooling tower to reduce the parasites of the molten salt power tower.

Keywords: molten salt power tower, natural draft dry cooling, commercial scale, power block, harsh winter climate

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Authors: Jan Dahlhaus, Alejandro Cardenas Miranda, Frederik Scholer, Maximilian Leonhardt, Matthias Moullion, Frank Beutenmuller, Julia Eckhardt, Josef Wasner, Frank Nittel, Sebastian Stoll, Devin Atukalp, Daniel Folgmann, Tobias Mayer, Obrad Dordevic, Paul Riley, Jean-Marc Le Peuvedic

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Electrical and hybrid aerospace technologies pose very challenging demands on the battery pack – especially with respect to weight and power. In the Clean Sky 2 research project LiBAT (funded by the EU), the consortium is currently building an ambitious prototype with state-of-the art cells that shows the potential of an intelligent pack design with a high level of integration, especially with respect to thermal management and power electronics. For the latter, innovative multi-level-inverter technology is used to realize the required power converting functions with reduced equipment. In this talk the key approaches and methods of the LiBat project will be presented and central results shown. Special focus will be set on the simulative methods used to support the early design and development stages from an overall system perspective. The applied methods can efficiently handle multiple domains and deal with different time and length scales, thus allowing the analysis and optimization of overall- or sub-system behavior. It will be shown how these simulations provide valuable information and insights for the efficient evaluation of concepts. As a result, the construction and iteration of hardware prototypes has been reduced and development cycles shortened.

Keywords: electric aircraft, battery, Li-ion, multi-level-inverter, Novec

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Authors: Martyna Ekiert, Andrzej Mlyniec

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Tendons are the biological structures, which primary function is to transfer force generated by muscles to the bones. Unfortunately, damages of tendons are also one of the most common injuries of the human musculoskeletal system. For the most severe cases of tendon rupture, such as the tear of calcaneus tendon or anterior cruciate ligament of the knee, a surgical procedure is the only possible way of full recovery. Tendons used as biological grafts are usually subjected to the process of deep freezing and subsequent thawing. This, in particular for multiple freezing/thawing cycles, may result in changes of tendon internal structure causing deterioration of mechanical properties of the tissue. Therefore, studies on the influence of freezing on tendons biomechanics, including internal water content in soft tissue, seems to be greatly needed. An experimental study of the influence of freezing on mechanical properties of the tendon was performed on fascicles samples dissected form bovine flexor tendons. The preparation procedure was performed with the presence of 0.9% saline solution in order to prevent an excessive tissue drying. All prepared samples were subjected to the different number of freezing/thawing cycles. For freezing part of the protocol we used -80°C temperature while for slow thawing we used fridge temperature (4°C) combined with equalizing temperatures in the standard state (25°C). After final thawing, the mechanical properties of each sample was examined using cyclic loading test. Our results may contribute for better understanding of negative effects of soft tissues freezing, resulting from abnormal thermal expansion of water. This also may help to determine the limit of freezing/thawing cycles disqualifying tissue for surgical purposes and thus help optimize tissues storage conditions.

Keywords: freezing, soft tissue, tendon, bovine fascicles

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Authors: Thaminda Liyanage, Chamila Shamika Kurukulasuriya

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Introduction: Morbid obesity has been successfully treated with bariatric surgery for over 60 years. Although operative procedures have improved and associated complications have reduced substantially, surgery still carries the risk of post-operative malabsorption, malnutrition and a range of gastrointestinal disorders. Overweight by itself can impair libido in both sexes and cause erectile dysfunction in males by inducing a state of hypogonadotropic hypogonadism, proportional to the degree of obesity. Impact of weight reduction on libido and sexual activity remains controversial, however it is broadly accepted that weight loss improves sexual drive. Zinc deficiency, subsequent to malabsorption, may lead to impaired testosterone synthesis in men while excessive and/or rapid weight loss in females may result in reversible amenorrhoea leading to sub-fertility. Methods: We describe a 37 year old male, 6 years post Roux-en-Y gastric bypass surgery, who presented with erectile dysfunction, loss of libido, worsening fatigue and generalized weakness for 4 months. He also complained of constipation and frequent muscle cramps but denied having headache, vomiting or visual disturbances. Patient had lost 38 kg of body weight post gastric bypass surgery over four years {135kg (BMI 42.6 kg/m2) to 97 kg (BMI 30.6 kg/m2)} and the weight had been stable for past two years. He had no recognised co-morbidities at the time of the surgery and noted marked improvement in general wellbeing, physical fitness and psychological confident post surgery, up until four months before presentation. Clinical examination revealed dry pale skin with normal body hair distribution, no thyroid nodules or goitre, normal size testicles and normal neurological examination with no visual field defects or diplopia. He had low serum testosterone, follicular stimulating hormone (FSH), luteinizing hormone (LH), T3, T4, thyroid stimulating hormone (TSH), insulin like growth factor 1 (IGF-1) and 24-hour urine cortisol levels. Serum cortisol demonstrated an appropriate rise to ACTH stimulation test but growth hormone (GH) failed increase on insulin tolerance test. Other biochemical and haematological studies were normal, except for low zinc and folate with minimally raised liver enzymes. MRI scan of the head confirmed a solid pituitary mass with no mass effect on optic chiasm. Results: In this patient clinical, biochemical and radiological findings were consistent with anterior pituitary dysfunction. However, there were no features of raised intracranial pressure or neurological compromise. He was commenced on appropriate home replacement therapy and referred for neurosurgical evaluation. Patient reported marked improvement in his symptoms, specially libido and erectile dysfunction, on subsequent follow up visits. Conclusion: Sexual dysfunction coupled with non specific constitutional symptoms has multiple aetiologies. Clinical symptoms out of proportion to nutritional deficiencies post bariatric surgery should be thoroughly investigated. Close long term follow up is crucial for overall success.

Keywords: obesity, bariatric surgery, erectile dysfunction, loss of libido

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Authors: Oscar Bareiro, Johannes Sackmann, Thomas Gries

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Carbon fiber reinforced polymer composites (CFRP) are used in a wide variety of applications due to its advantageous properties and design versatility. The braiding process enables the manufacture of components with good toughness and fatigue strength. However, failure mechanisms of CFRPs are complex and still present challenges associated with their maintenance and repair. Within the broad scope of structural health monitoring (SHM), strain monitoring can be applied to composite materials to improve reliability, reduce maintenance costs and safely exhaust service life. Traditional SHM systems employ e.g. fiber optics, piezoelectrics as sensors, which are often expensive, time consuming and complicated to implement. A cost-efficient alternative can be the exploitation of the conductive properties of fiber-based sensors such as carbon, copper, or constantan - a copper-nickel alloy – that can be utilized as sensors within composite structures to achieve strain monitoring. This allows the structure to provide feedback via electrical signals to a user which are essential for evaluating the structural condition of the structure. This work presents a strategy for the in-process integration of resistance-based sensors (Elektrisola Feindraht AG, CuNi23Mn, Ø = 0.05 mm) into textile preforms during its manufacture via the braiding process (Herzog RF-64/120) to achieve strain monitoring of braided composites. For this, flat samples of instrumented composite laminates of carbon fibers (Toho Tenax HTS40 F13 24K, 1600 tex) and epoxy resin (Epikote RIMR 426) were manufactured via vacuum-assisted resin infusion. These flat samples were later cut out into test specimens and the integrated sensors were wired to the measurement equipment (National Instruments, VB-8012) for data acquisition during the execution of mechanical tests. Quasi-static tests were performed (tensile, 3-point bending tests) following standard protocols (DIN EN ISO 527-1 & 4, DIN EN ISO 14132); additionally, dynamic tensile tests were executed. These tests were executed to assess the sensor response under different loading conditions and to evaluate the influence of the sensor presence on the mechanical properties of the material. Several orientations of the sensor with regards to the applied loading and sensor placements inside the laminate were tested. Strain measurements from the integrated sensors were made by programming a data acquisition code (LabView) written for the measurement equipment. Strain measurements from the integrated sensors were then correlated to the strain/stress state for the tested samples. From the assessment of the sensor integration approach it can be concluded that it allows for a seamless sensor integration into the textile preform. No damage to the sensor or negative effect on its electrical properties was detected during inspection after integration. From the assessment of the mechanical tests of instrumented samples it can be concluded that the presence of the sensors does not alter significantly the mechanical properties of the material. It was found that there is a good correlation between resistance measurements from the integrated sensors and the applied strain. It can be concluded that the correlation is of sufficient accuracy to determinate the strain state of a composite laminate based solely on the resistance measurements from the integrated sensors.

Keywords: braiding process, in-process sensor integration, instrumented composite material, resistance-based sensor, strain monitoring

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Authors: Mina Ganji Morad, Maziar Azadisoleimanieh, Sina Ganji Morad

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A green roof is formed by green plants alive and has many positive impacts in the regional climatic, as well as indoor. Green roof system to prevent solar radiation plays a role in the cooling space. The cooling is done by reducing thermal fluctuations on the exterior of the roof and by increasing the roof heat capacity which cause to keep the space under the roof cool in the summer and heating rate increases during the winter. A roof garden is one of the recommended ways to reduce energy consumption in large cities. Despite the scale of the city green roofs have effective functions, such as beautiful view of city and decontaminating the urban landscape and reduce mental stress, and in an exchange of energy and heat from outside to inside spaces. This article is based on a review of 20 articles and 10 books and valid survey results on the positive effects of green roofs to prevent energy waste in the building. According to these publications, three of the conventional roof, green roof typical and green roof with certain administrative details (layers of glass) and the use of resistant plants and shrubs have been analyzed and compared their heat transfer. The results of these studies showed that one of the best green roof systems for mountainous climate is tree and shrub system that in addition to being resistant to climate change in mountainous regions, will benefit from the other advantages of green roof. Due to the severity of climate change in mountainous areas it is essential to prevent the waste of buildings heating and cooling energy. Proper climate design can greatly help to reduce energy.

Keywords: green roof, heat transfer, reducing energy consumption, mountainous areas, sustainable architecture

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Authors: Ayodeji Sowale, Athanasios Kolios, Beatriz Fidalgo, Tosin Somorin, Aikaterini Anastasopoulou, Alison Parker, Leon Williams, Ewan McAdam, Sean Tyrrel

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Recently, energy recovery systems are thriving and raising attention in the power generation sector, due to the request for cleaner forms of energy that are friendly and safe for the environment. This has created an avenue for cogeneration, where Combined Heat and Power (CHP) technologies have been recognised for their feasibility, and use in homes and small-scale businesses. The efficiency of combustors and the advantages of the free piston Stirling engines over other conventional engines in terms of output power and efficiency, have been observed and considered. This study presents the numerical analysis of a micro-combustor with a free piston Stirling engine in an integrated model of a Nano Membrane Toilet (NMT) unit. The NMT unit will use the micro-combustor to produce waste heat of high energy content from the combustion of human waste and the heat generated will power the free piston Stirling engine which will be connected to a linear alternator for electricity production. The thermodynamic influence of the combustor on the free piston Stirling engine was observed, based on the heat transfer from the flue gas to working gas of the free piston Stirling engine. The results showed that with an input of 25 MJ/kg of faecal matter, and flue gas temperature of 773 K from the micro-combustor, the free piston Stirling engine generates a daily output power of 428 W, at thermal efficiency of 10.7% with engine speed of 1800 rpm. An experimental investigation into the integration of the micro-combustor and free piston Stirling engine with the NMT unit is currently underway.

Keywords: free piston stirling engine, micro-combustor, nano membrane toilet, thermodynamics

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Authors: Kubra Dogan, Fatih Tornuk

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Due to increasing consumer demand for the high-quality food products and awareness regarding the health benefits of different nutrients in food minimal processing becomes more popular in modern food preservation. To date, heat treatment is often used for inactivation of spoilage microorganisms in foods. However, it may cause significant changes in the quality and nutritional properties of food. In order to overcome the detrimental effects of heat treatment, several alternatives of non-thermal microbial inactivation processes have been investigated. Ultraviolet (UV) inactivation is a promising and feasible method for better quality and longer shelf life as an alternative to heat treatment, which aims to inhibit spoilage and pathogenic microorganisms and to inactivate the enzymes in vegetable juice production. UV-C is a sub-class of UV treatment which shows the highest microcidal effect between 250-270 nm. The wavelength of 254 nm is used for the surface disinfection of certain liquid food products such as vegetable juice. Effects of UV-C treatment on microbiological load and quality parameter of vegetable juice which is a mix of celery, carrot, lemon and orange was investigated. Our results showed that storing of UV-C applied vegetable juice for three months, reduced the count of TMAB by 3.5 log cfu/g and yeast-mold by 2 log cfu/g compared to control sample. Total phenolic content was found to be 514.3 ± 0.6 mg gallic acid equivalent/L, and there wasn’t a significant difference compared to control. The present work suggests that UV-C treatment is an alternative method for disinfection of vegetable juice since it enables adequate microbial inactivation, longer shelf life and has minimal effect on degradation of quality parameters of vegetable juice.

Keywords: heat treatment, phenolic content, shelf life, ultraviolet (UV-C), vegetable juice

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Authors: Sumandeep Kaur, Allam Srinivasa Rao, Mula Jayasimhadri

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In recent years, rare earth (RE) ions doped inorganic luminescent materials are seeking great attention due to their excellent physical and chemical properties. These materials offer high thermal and chemical stability and exhibit good luminescence properties due to the presence of RE ions. The luminescent properties of these materials are attributed to their intra-configurational f-f transitions in RE ions. A series of Tb³⁺ doped calcium aluminozincate has been synthesized via sol-gel method. The structural and morphological studies have been carried out by recording X-ray diffraction patterns and SEM image. The luminescent spectra have been recorded for a comprehensive study of their luminescence properties. The XRD profile reveals the single-phase orthorhombic crystal structure with an average crystallite size of 65 nm as calculated by using DebyeScherrer equation. The SEM image exhibits completely random, irregular morphology of micron size particles of the prepared samples. The optimization of luminescence has been carried out by varying the dopant Tb³⁺ concentration within the range from 0.5 to 2.0 mol%. The as-synthesized phosphors exhibit intense emission at 544 nm pumped at 478 nm excitation wavelength. The optimized Tb³⁺ concentration has been found to be 1.0 mol% in the present host lattice. The decay curves show bi-exponential fitting for the as-synthesized phosphor. The colorimetric studies show green emission with CIE coordinates (0.334, 0.647) lying in green region for the optimized Tb³⁺ concentration. This report reveals the potential utility of Tb³⁺ doped calcium aluminozincate phosphors for display and solid-state lighting devices.

Keywords: concentration quenching, phosphor, photoluminescence, XRD

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Authors: N. K. Thakur

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A major proportion of the formations drilled for the production of hydrocarbons consists of clay containing shales. The petroleum industry has hugely investigated the role of clay minerals and their subsequent effect on wellbore stability during the drilling and production of hydrocarbons. It has been found that when the shale formation comes in contact with water-based drilling fluid, the interaction of clay minerals like montmorillonite with infiltrated water leads to hydration of the clay minerals, which causes shale swelling. When shale swelling proceeds further, it may lead to major drilling complications like caving, pipe sticking, which invariably influences wellbore stability, wellbore diameter, the mechanical strength of shale, stress distribution in the wellbore, etc. These problems ultimately lead to an increase in nonproductive time and additional costs during drilling. Several additives are used to prevent shale instability. Among the popular additives used for shale inhibition in drilling muds, ionic liquids and nanoparticles are emerging to be the best additives. The efficiency of the proposed additives will be studied and compared with conventional clay inhibitors like KCl. The main objective is to develop a highly efficient water-based mud for mitigating shale instability and reducing fluid loss which is environmentally friendly and does not alter the formation permeability. The use of nanoparticles has been exploited to enhance the rheological and fluid loss properties in water-based drilling fluid ionic liquid have attracted significant research interest due to its unique thermal stability. It is referred to as ‘green chemical’. The preliminary experimental studies performed are promising. The application of more effective mud additives is always desirable to make the drilling process techno-economically proficient.

Keywords: ionic liquid, shale inhibitor, wellbore stability, unconventional

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Authors: Aleksandra Łochowicz, Daria Świętochowska, Loredano Pollegioni, Nazim Ocal, Franck Charmantray, Laurence Hecquet, Katarzyna Szymańska

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Multienzymatic cascade reactions are nowadays widely used in pharmaceutical, chemical and cosmetics industries to produce high valuable compounds. They can be carried out in two ways, step by step and one-pot. If two or more enzymes are in the same reaction vessel is necessary to work out the compromise to run the reaction in optimal conditions for each enzyme. So far most of the reports of multienzymatic cascades concern on usage of free enzymes. Unfortunately using free enzymes as catalysts of reactions accomplish high cost. What is more, free enzymes are soluble in solvents which makes reuse impossible. To overcome this obstacle enzymes can be immobilized what provides heterogeneity of biocatalyst that enables reuse and easy separation of the enzyme from solvents and reaction products. Usually, immobilization increase also the thermal and operational stability of enzyme. The advantages of using immobilized multienzymes are enhanced enzyme stability, improved cascade enzymatic activity via substrate channeling, and ease of recovery for reuse. The one-pot immobilized multienzymatic cascade can be carried out in mixed or coimmobilized type. When biocatalysts are coimmobilized on the same carrier the are in close contact to each other which increase the reaction rate and catalytic efficiency, and eliminate the lag time. However, in this type providing the optimal conditions both in the process of immobilization and cascade reaction for each enzyme is complicated. Herein, we examined immobilization of 3 enzymes: D-amino acid oxidase from Rhodotorula gracilis, commercially available catalase and transketolase from Geobacillus stearothermophilus. As a support we used silica monoliths with hierarchical structure of pores. Then we checked their stability and reusability in one-pot cascade of L-erythrulose and hydroxypuryvate acid synthesis.

Keywords: biocatalysts, enzyme immobilization, multienzymatic reaction, silica carriers

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Authors: Wen-Jay Lee, Kuo-Ning Chiang

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The graphene binding with silicon substrate has apparently Schottky barriers property, which can be used in the application of solar cell and light source. Because graphene has only one atom layer, the atomistic structure of graphene binding with the silicon surface plays an important role to affect the properties of graphene. In this work, temperature effect on the morphology of graphene sheet attached on different crystal planes of silicon substrates are investigated by Molecular dynamics (MD) (LAMMPS, developed by Sandia National Laboratories). The results show that the covered graphene sheet would cause the structural deformation of the surface Si atoms of stubtrate. To achieve a stable state in the binding process, the surface Si atoms would adjust their position and fit the honeycomb structure of graphene after the graphene attaches to the Si surface. The height contour of graphene on different plane of silicon surfaces presents different pattern, leading the local residual stress at the interface. Due to the high density of dangling bond on the Si (111)7x7 surface, the surface of Si(111)7x7 is not matching with the graphene so well in contrast with Si(100)2x1and Si(111)2x1. Si(111)7x7 is found that only partial silicon adatoms are rearranged on surface after the attachment when the temperature is lower than 200K, As the temperature gradually increases, the deformation of surface structure becomes significant, as well as the residue stress. With increasing temperature till the 815K, the graphene sheet begins to destroy and mixes with the silicon atoms. For the Si(100)2x1 and Si(111)2x1, the silicon surface structure keep its structural arrangement with a higher temperature. With increasing temperature, the residual stress gradually decrease till a critical temperatures. When the temperature is higher than the critical temperature, the residual stress gradually increases and the structural deformation is found on the surface of the Si substrates.

Keywords: molecular dynamics, graphene, silicon, Schottky barriers, interface

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Authors: Vijay Samuel, Tina Thekkekkara, Shoma Ganguly

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There is no reported Hanta Seoul virus infection in children in the UK so far, making it quite challenging for clinicians in diagnosing, predicting and prognosticating the outcome of the infection to patients and parents. We report a case of a ten-year-old girl who presented with pyrexia associated with headache, photophobia and abdominal pain. The family had recently acquired two pet rats six weeks ago. She appeared flushed with peri-oral pallor, coated the strawberry tongue, inflamed tonsils and bilateral cervical lymphadenopathy. Her liver and splenic edges were palpable. Investigations showed that she was thrombocytopenic with deranged renal and liver functions. An ultrasound abdomen demonstrated a mildly enlarged spleen, peripancreatic lymph node and an acalculous cholecystitis. In view of her clinical presentation, a diagnosis of leptospirosis was considered and she was commenced on intravenous benzylpenicillin. The following day she became oliguric, developed significant proteinuria and her renal function deteriorated. Following conservative management, her urine output gradually improved along with her renal function, proteinuria and thrombocytopaenia. Serology for leptospirosis and various other viruses were negative. Following discussion with the Rare and Imported Pathogens Laboratory at Porton hanta virus serology was requested and found to be strongly positive for Seoul hanta virus. Following discharge she developed palpitations, fatigue, severe headache and cognitive difficulties including memory loss and difficulties in spelling, reading and mathematics. Extensive investigations including ECG, MRI brain and CSF studies were performed and revealed no significant abnormalities. Since 2012, there have been six cases of acute kidney injury due to Hantavirus infection in the UK. Two cases were from the Humber region and were exposure to wild rats and the other four were exposed to specially bred pet fancy rats. Hanta virus infections can cause mild flu like symptoms but two clinical syndromes are associated with severe disease including haemorrhagic fever with renal syndrome, which may be associated with thrombocytopenia and Hantavirus cardiopulmonary syndrome. Neuropsychological impairments reported following hantavirus pulmonary syndrome and following Puumala virus infection have been reported. Minor white matter lesions were found in about half of the patients investigated with MRI brain. Seoul virus has a global distribution owing to the dispersal of its carrier host rats, through global trade. Several ports in the region could explain the possible establishment of Seoul virus in local populations of rats in the Yorkshire and Humber region. The risk of infection for occupationally exposed groups is 1-3% compared to 32.9% for specialist pet rat owners. The report highlight’s the importance of routinely asking about pets in the family. We hope to raise awareness of the emergence of hantavirus infection in the UK, particularly in the Yorkshire and Humber region. Clinicians should consider hantavirus infection as a potential cause of febrile illness causing renal impairment in children. Awareness of the possible neuro-cognitive sequele would help the clinicians offer appropriate information and support to children and their families. Contacting Rare and Imported Pathogens Laboratory at Porton is a useful resource for clinicians in UK when they consider unusual infections.

Keywords: Seoul hantavirus in child Porton, UK Acute kidney injury

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