Search results for: multi-impeller pump

Authors: Omar bin Mihat

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The number of sudden deaths is increasing over the past years. These deaths occur not during physical activities but upon cessation. Post-mortem confirms these deaths as cardiac arrest non-specifically. Congenital heart disease is a condition undiagnosed whereby only surface upon physical exertion leading to sudden death is unavoidable. Channelopathy, a condition that refers to any disease from the defect in iron-channel function, particularly the sodium-potassium pump, during the cessation of the exercise can be controlled. The derivation of heart rate return (HRrtn) is a procedure of a control cooling down process according to the heart rate (HR). Empirically, potassium rises linearly with intensity and falls sharply upon abrupt cessation of exertion, resulting in fatal arrhythmia due to hypokalaemia. It is vital that the flux of potassium should be maintained within the normal range during physical activities. To achieve this, the dosage of physical exertion (exercise) should be identified. Various percentages of the intensity of maximum heart rate (MHR) will precipitate different adaptations and remodeling of various organs. 70% of MHR will surface physiological adaptations, including enhancement of endurance, fitness level, and general health, and there was no significant rise of serum potassium (K+) during the entire phase of the treadmill brisk walk at a different rate of perceived exertion (RPE) from the subject of various fitness background. There was also no significant rise in blood pressure (BP) during the entire phase of the treadmill brisk walk, substantiating 70% MHR is the safe dosage across different parameters of health and fitness level.

Keywords: potassium, maximal heart rate, exercise dosage, fitness level

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Authors: Syazwani Idrus, Charles Banks, Sonia Heaven

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The effect of osmotic stress was carried out to determine the ability for biogas production in two types of digesters; anaerobic sludge blanket and anaerobic filters in treating wheat straw washed water. Two anaerobic filters (AF1 and 2) and two UASB reactors (U1 and 2) with working volumes of 1.5 L were employed at mesophilic temperatures (37°C). Digesters AF1 and two were seeded with an inoculum which had previously been fed on with a synthetic wastewater includingSodium Chloride and Potassium Chloride. Digesters U1 and two were seeded with 1 kg wet weight of granular sludge which had previously been treating paper mill effluent. During the first 48 days, all digesters were successfully acclimated with synthetic wastewater (SW) to organic loading rate (OLR) of 6 g COD l^-1 day-1. Specific methane production (SMP) of 0.333 l CH4 g-1 COD). The feed was then changed to wash water from a washing operation to reduce the salt content of wheat straw (wheat straw wash water, WSW) at the same OLR. SMP fell sharply in all reactors to less than 0.1 l CH4 g^-1 COD, with the AF affected more than the UASB. The OLR was reduced to 2.5 g COD l^-1 day^-1 to allow adaptation to WSW, and both the UASB and the AF reactors achieved an SMP of 0.21 l CH4 g^-1 COD added at 82% of COD removal. This study also revealed the accumulation of potassium (K) inside the UASB granules to a concentration of 4.5 mg K g^-1 wet weight of granular sludge. The phenomenon of lower SMP and accumulation of K indicates the effect of osmotic stress when fed on WSW. This finding is consistent with the theory that methanogenic organisms operate a Potassium pump to maintain ionic equilibrium, and as this is an energy-driven process, it will, therefore, reduce the overall methane yield.

Keywords: wheat straw wash water, upflow anaerobic sludge blanket, anaerobic filter, specific methane production, osmotic stress

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Authors: Daofan Guo, Dong Yang

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For decades, well logging with coiled tubing has relied solely on surface data such as pump pressure, wellhead pressure, depth counter, and weight indicator readings. While this data serves the oil industry well, modern smart logging utilizes real-time downhole information, which automatically increases operational efficiency and optimizes intervention qualities. For example, downhole pressure, temperature, and depth measurement data can be transmitted through the electro-optical hybrid cable in the coiled tubing to surface operators on a real-time base. This paper mainly introduces the unique structural features and various applications of the electro-optical hybrid cables which were deployed into downhole with the help of coiled tubing technology. Fiber optic elements in the cable enable optical communications and distributed measurements, such as distributed temperature and acoustic sensing. The electrical elements provide continuous surface power for downhole tools, eliminating the limitations of traditional batteries, such as temperature, operating time, and safety concerns. The electrical elements also enable cable telemetry operation of cable tools. Both power supply and signal transmission were integrated into an electro-optical hybrid cable, and the downhole information can be captured by downhole electrical sensors and distributed optical sensing technologies, then travels up through an optical fiber to the surface, which greatly improves the accuracy of measurement data transmission.

Keywords: electro-optical hybrid cable, underground photoelectric composite cable, seismic cable, coiled tubing, real-time monitoring

Procedia PDF Downloads 104

Authors: Przemyslaw Nogly, Tobias Weinert, Daniel James, Sergio Carbajo, Dmitry Ozerov, Antonia Furrer, Dardan Gashi, Veniamin Borin, Petr Skopintsev, Kathrin Jaeger, Karol Nass, Petra Bath, Robert Bosman, Jason Koglin, Matthew Seaberg, Thomas Lane, Demet Kekilli, Steffen Brünle, Tomoyuki Tanaka, Wenting Wu, Christopher Milne, Thomas A. White, Anton Barty, Uwe Weierstall, Valerie Panneels, Eriko Nango, So Iwata, Mark Hunter, Igor Schapiro, Gebhard Schertler, Richard Neutze, Jörg Standfuss

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Ultrafast isomerization of retinal is the primary step in a range of photoresponsive biological functions including vision in humans and ion-transport across bacterial membranes. We studied the sub-picosecond structural dynamics of retinal isomerization in the light-driven proton pump bacteriorhodopsin using an X-ray laser. Twenty snapshots with near-atomic spatial and temporal resolution in the femtosecond regime show how the excited all-trans retinal samples conformational states within the protein binding pocket prior to passing through a highly-twisted geometry and emerging in the 13-cis conformation. The aspartic acid residues and functional water molecules in proximity of the retinal Schiff base respond collectively to formation and decay of the initial excited state and retinal isomerization. These observations reveal how the protein scaffold guides this remarkably efficient photochemical reaction.

Keywords: bacteriorhodopsin, free-electron laser, retinal isomerization mechanism, time-resolved crystallography

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Authors: Amando A. Radomes Jr., LLoyd Jun Benjamin T. Embernatre, Cherssy Kaye F. Eviota, Krizia Allyn L. Nunez, Jose Thaddeus B. Roble III

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Sitio Kantaling is one of the 34 villages in Danao City, Cebu, in the central Philippines. As of 2015, the eight households in the mountainous village extending over 40 hectares of land area, including 12 hectares of arable land, are the source of over a fifth of the agricultural products that go into the city. Over the years, however, the local government had been concerned with the decline in agricultural productivity because increasing number of residents are migrating into the urban areas of the region to look for better employment opportunities. One of the major reasons for the agricultural productivity decline is underdeveloped irrigation infrastructure. The local government had partnered with the University of San Carlos to conduct research on developing an irrigation system that could sustainably meet both agricultural and household consumption needs. From a macro-perspective, a dynamic simulation model was developed to understand the long-term behavior of the status quo and proposed the system. Data on population, water supply and demand, household income, and urban migration were incorporated in the 20-year horizon model. The study also developed a smart irrigation system design. Instead of using electricity to pump water, a network of aqueducts with three main nodes had been designed and strategically located to take advantage of gravity to transport water from a spring. Simulation results showed that implementing a sustainable irrigation system would be able to significantly contribute to the socio-economic progress of the local community.

Keywords: agriculture, aqueduct, simulation, sustainable irrigation system

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Authors: Dina Atmani-Kilani, Farah Yous, Djebbar Atmani

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The etiology of peptic ulcer is closely related to stress, excessive consumption of nonsteroidal anti-inflammatory drugs, or ethanol. Clematis flammula (Ranunculaceae) is a medicinal plant widely used by rural populations to treat inflammatory disorders. This study was designed to assess the gastroprotective potential of C. flammula extracts. Gastric ulcer was induced by stress, indomethacin, HCl / ethanol, and absolute ethanol on NMRI-type mice. The antioxidant potency of the ethanolic extract of Clematis flammula (EECF) was evaluated on catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) activities. Glutathione (GSH) and malonaldehyde (MDA) levels were also quantified. The anti-inflammatory potential was evaluated through the effect of EECF on myeloperoxidase activity (MPO) and vascular permeability. Complementary tests concerning the quantification of mucus levels, gastric motility, inhibition of ATPase H+/K+activity, as well as a histopathological study were also undertaken to explore the mechanism of action of the EECF. The EECF exhibited a significant (p <0.001) and optimal (100 mg/kg) gastroprotective effect by elevating SOD, CAT, and GSH levels, thereby minimizing the production of MDA and lowering the activity of MPO and vascular permeability. EECF also increased the rate of mucus production, decreased gastric motility, and completely suppressed the H+/K+ ATPase activity. Histopathological study confirmed the effectiveness of the extract in the prevention of peptic ulcer. The results obtained in this study demonstrated the gastro-protective effect of EECF via acidic antioxidant, anti-inflammatory, cytoprotective and anti-secretory mechanisms, which may justify its use as a substitute in peptic ulcer treatment.

Keywords: clematis flammula, superoxide dismutase, myeloperoxidase, ATPase, pump

Procedia PDF Downloads 172

Authors: Pragathi Gurumurthy, Christina Hagen, Patricia Ulloa, Martin A. Koch, Thorsten M. Buzug

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Obstructive sleep apnea (OSA) is a sleep disorder where the patient suffers a disturbed airflow during sleep due to partial or complete occlusion of the pharyngeal airway. Recently, numerical simulations have been used to better understand the mechanism of pharyngeal collapse. However, to gain confidence in the solutions so obtained, an experimental validation is required. Therefore, in this study an experimental validation of computational fluid dynamics (CFD) used for the study of human pharyngeal flow patterns during OSA is performed. A stationary incompressible Navier-Stokes equation solved using the finite element method was used to numerically study the flow patterns in a computed tomography-based human pharynx model. The inlet flow rate was set to 250 ml/s and such that a flat profile was maintained at the inlet. The outlet pressure was set to 0 Pa. The experimental technique used for the validation of CFD of fluid flow patterns is phase contrast-MRI (PC-MRI). Using the same computed tomography data of the human pharynx as in the simulations, a phantom for the experiment was 3 D printed. Glycerol (55.27% weight) in water was used as a test fluid at 25°C. Inflow conditions similar to the CFD study were simulated using an MRI compatible flow pump (CardioFlow-5000MR, Shelley Medical Imaging Technologies). The entire experiment was done on a 3 T MR system (Ingenia, Philips) with 108 channel body coil using an RF-spoiled, gradient echo sequence. A comparison of the axial velocity obtained in the pharynx from the numerical simulations and PC-MRI shows good agreement. The region of jet impingement and recirculation also coincide, therefore validating the numerical simulations. Hence, the experimental validation proves the reliability and correctness of the numerical simulations.

Keywords: computational fluid dynamics, experimental validation, phase contrast-MRI, obstructive sleep apnea

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Authors: Jin Hwa Yang, Hwang Bae, Sung Uk Ryu, Byong Guk Jeon, Sung Jae Yi, Hyun Sik Park

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Experimental studies using a large-scale thermal-hydraulic integral test facility, System–integrated Modular Advanced Reactor Integral Test Loop (SMART-ITL), have been carried out to validate the performance of the prototype, SMART. After Fukushima accident, the passive safety systems have been dealt as important designs for retaining of nuclear safety. One of the concerned scenarios for evaluating the passive safety system is a Complete Loss of Coolant Flow (CLOF). The flowrate of coolant in the primary system is maintained by Reactor Coolant Pump (RCP). When the supply of electric power of RCP is shut off, the flowrate of coolant decreases sharply, and the temperature of the coolant increases rapidly. Therefore, the reactor trip signal is activated to prevent the over-heating of the core. In this situation, Passive Residual Heat Removal System (PRHRS) plays a significant role to assure the soundness of the SMART. The PRHRS using a two-phase natural circulation is a passive safety system in the SMART to eliminate the heat of steam generator in the secondary system with heat exchanger submarined in the Emergency Cooling Tank (ECT). As the RCPs continue to coast down, inherent natural circulation in the primary system transfers heat to the secondary system. The transferred heat is removed by PRHRS in the secondary system. In this paper, the progress of the CLOF accident is described with experimental data of transient condition performed by SMART-ITL. Finally, the capability of passive safety system and inherent natural circulation will be evaluated.

Keywords: CLOF, natural circulation, PRHRS, SMART-ITL

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Authors: A. Aljohani, D. Burke, D. Clarke, M. Gormally, M. Byrne, G. Fleming

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Introduction: House Dust Mites (HDMs) are a source of allergen particles embedded in textiles and furnishings. Vacuum sampling is commonly used to recover and determine the abundance of HDMs but the efficiency of this method is less than standardized. Here, the efficiency of recovery of HDMs was evaluated from home-associated textiles using vacuum sampling protocols.Methods/Approach: Living Mites (LMs) or dead Mites (DMs) House Dust Mites (Dermatophagoides pteronyssinus: FERA, UK) were separately seeded onto the surfaces of Smooth Cotton, Denim and Fleece (25 mites/10x10cm2 squares) and left for 10 minutes before vacuuming. Fabrics were vacuumed (SKC Flite 2 pump) at a flow rate of 14 L/min for 60, 90 or 120 seconds and the number of mites retained by the filter (0.4μm x 37mm) unit was determined. Vacuuming was carried out in a linear direction (Protocol 1) or in a multidirectional pattern (Protocol 2). Additional fabrics with LMs were also frozen and then thawed, thereby euthanizing live mites (now termed EMs). Results/Findings: While there was significantly greater (p=0.000) recovery of mites (76% greater) in fabrics seeded with DMs than LMs irrespective of vacuuming protocol or fabric type, the efficiency of recovery of DMs (72%-76%) did not vary significantly between fabrics. For fabrics containing EMs, recovery was greatest for Smooth Cotton and Denim (65-73% recovered) and least for Fleece (15% recovered). There was no significant difference (p=0.99) between the recovery of mites across all three mite categories from Smooth Cotton and Denim but significantly fewer (p=0.000) mites were recovered from Fleece. Scanning Electron Microscopy images of HMD-seeded fabrics showed that live mites burrowed deeply into the Fleece weave which reduced their efficiency of recovery by vacuuming. Research Implications: Results presented here have implications for the recovery of HDMs by vacuuming and the choice of fabric to ameliorate HDM-dust sensitization.

Keywords: allergy, asthma, dead, fabric, fleece, live mites, sampling

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Authors: Lahaina U. Dilangalen

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Using descriptive-experimental research methods, this study aimed to identify the main resources of water, assessed the water quality, sanitation and hygiene practices, and extent of implementation. Complete enumeration was done in 28 elementary public schools of Datu Odin Sinsuat Municipality. Questionnaires were given to the school advisers. Water samples were obtained from the same schools and were submitted to the Department of Science and Technology (DOST) Region XII for microbial analysis, specifically the presence of fecal coliform bacteria. Four water resources such as hand pump, faucet, deep well and spring were found being used in the 28 schools. Of water resources, the only treated was from the faucet. Most of the schools used the water for drinking and washing. Two schools strongly agreed, nine schools agreed and seventeen schools disagreed that they implemented DepEd Order no.56 s. 2009. In addition, two schools strongly agreed and twenty six agreed that they implemented DepEd Order No. 65 s. 2009. Five schools had water supply that were safe to drink while sixteen schools had water supply that were not safe to drink due to high fecal coliform count and did not undergo chemical treatment. The only safe for drinking were water resources that came from faucet because they were chemically treated. Seven out of 28 schools did not have water supply due to their location in mountainous areas. More than half of the schools did not comply with the DepEd Order No. 56 s. 2009 due to the lack of funds and support from the PTA and LGU. It is recommended that the Department of Education must have an urgent assessment of implementing both DepEd Orders No.56 and 65, to assure that the schoolchildren be protected from water and sanitation related ailments. Also, all water resources that are not treated must be used for washing only. Ideally, all the water resources must be treated to assure the safety of all school constituents. Moreover, the school administrators and teachers in the municipality must be provided copies of the results of this study for reference in implementing the said programs.

Keywords: assessment, drinking water, fecal coliform, groundwater

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Authors: Rebecca J. Hafner, Daniel Read, David Elmes

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The current research applies decision making theory in order to address the problem of increasing uptake of energy-efficient technologies in the market place, where uptake is currently slower than one might predict following rational choice models. Specifically, in two studies we apply the alignable/non-alignable features effect and explore the impact of varying information structure on the consumers’ preference for standard versus energy efficient technologies. As researchers in the Interdisciplinary centre for Storage, Transformation and Upgrading of Thermal Energy (i-STUTE) are currently developing energy efficient heating systems for homes and businesses, we focus on the context of home heating choice, and compare preference for a standard condensing boiler versus an energy efficient heat pump, according to experimental manipulations in the structure of prior information. In Study 1, we find that people prefer stronger alignable features when options are similar; an effect which is mediated by an increased tendency to infer missing information is the same. Yet, in contrast to previous research, we find no effects of alignability on option preference when options differ. The advanced methodological approach used here, which is the first study of its kind to randomly allocate features as either alignable or non-alignable, highlights potential design effects in previous work. Study 2 is designed to explore the interaction between alignability and construal level as an explanation for the shift in attentional focus when options differ. Theoretical and applied implications for promoting energy efficient technologies are discussed.

Keywords: energy-efficient technologies, decision-making, alignability effects, construal level theory, CO2 reduction

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Authors: Shanmugasundaram Selvadurai, Amal Chandran

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Small satellites have become an alternative low-cost solution for several missions to accomplish specific missions such as Earth imaging, Technology demonstration, Education, and other commercial purposes. Small satellite missions focusing on Infrared imaging applications require lower temperature for scientific instruments and such low temperature can be achieved only using external cryocoolers but the disadvantage is that they generate a large amount of waste heat. Existing passive thermal control techniques are not capable to handle such large thermal loads and hence one of the traditional active Thermal Control System (TCS) is studied for a small satellite configuration. This work aims to downscale the existing Mechanically Pumped Fluid Loop (MPFL) TCS to a 27U CubeSat platform for an imaginary scientific instrument. The temperature-sensitive detector in the instrument considered to be maintained between 130K and 150K to reduce dark current noise and increase the data quality. A Single-Phase fluid based MPFL is chosen for this system-level study and this TCS consists of a microfluid pump, a micro-cryocooler, a fluid accumulator, external heaters, flow regulators, and sensors. This work also explains the thermal control system architecture with a conceptual design, arrangement of all the components, and thermal analysis for different low orbit conditions. Sizing and extensive trade studies for the components are conducted and the results have shown that the Single-phase MPFL system is able to handle the given thermal loads and maintain the satellite’s interface temperature within the desired limit.

Keywords: active thermal control system, satellite thermal, mechanically pumped fluid loop system, cryogenics, cryocooler

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Authors: Abdullah Alnutayfat, Alexander Sutin

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One of the most important types of renewable energy resources is wind energy which can be produced by wind turbines. The blades of the wind turbine are exposed to the pressure of the harsh environment, which causes a significant issue for the wind power industry in terms of the maintenance cost and failure of blades. One of the reliable methods for blade inspection is the vibroacoustic structural health monitoring (SHM) method which examines information obtained from the structural vibrations of the blade. However, all vibroacoustic SHM techniques are based on comparing the structural vibration of intact and damaged structures, which places a practical limit on their use. Methods for nonlinear vibroacoustic SHM are more sensitive to damage and cracking and do not need to be compared to data from the intact structure. This paper presents the Vibro-Acoustic Modulation (VAM) method based on the modulation of high-frequency (probe wave) by low-frequency loads (pump wave) produced by the blade rotation. The blade rotation alternates bending stress due to gravity, leading to crack size variations and variations in the blade resonance frequency. This method can be used with the classical SHM vibration method in which the blade is excited by piezoceramic actuator patches bonded to the blade and receives the vibration response from another piezoceramic sensor. The VAM modification of this method analyzes the spectra of the detected signal and their sideband components. We suggest the VAM model as the simple mechanical oscillator, where the parameters of the oscillator (resonance frequency and damping) are varied due to low-frequency blade rotation. This model uses the blade vibration parameters and crack influence on the blade resonance properties from previous research papers to predict the modulation index (MI).

Keywords: wind turbine blades, damaged detection, vibro-acoustic structural health monitoring, vibro-acoustic modulation

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Authors: Oleg Sapelnikov, Ruslan Latypov, Darina Ardus, Samvel Aivazian, Andrey Shiryaev, Renat Akchurin

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OBJECTIVE: MAZE procedure is one of the most effective surgical methods in atrial fibrillation (AF) treatment. Nowadays we are all aware of its modifications. In our study we conducted clinical analysis of “Box lesion+” approach during MAZE procedure in two-year follow-up. METHODS: We studied the results of the open-heart on-pump procedures performed in our hospital from 2017 to 2018 years. Thirty-two (32) patients with atrial fibrillation (AF) were included in this study. Fifteen (15) patients had concomitant coronary bypass grafting and seventeen (17) patients had mitral valve repair. Mean age was 62.3±8.7 years; prevalence of men was admitted (56.1%). Mean duration of AF was 4.75±5.44 and 7.07±8.14 years. In all cases, we performed endocardial Cryo-MAZE procedure with one-time myocardium revascularization or mitral-valve surgery. All patients of this study underwent pulmonary vein (PV) isolation and ablation of mitral isthmus with additional isolation of LA posterior wall (Box-lesion+ procedure). Mean follow-up was 2 years. RESULTS: All cases were performed without any complications. Additional isolation of posterior wall did not prolong the operative time and artificial circulation significantly. Cryo-MAZE procedure directly lasted 20±2.1 min, the whole operation time was 192±24 min and artificial circulation time was 103±12 min. According to design of the study, we performed clinical investigation of the patients in 12 months and in 2 years from the initial procedure. In 12 months, the number of AF free patients 81.8% and 75.8% in two years of follow-up. CONCLUSIONS: Isolation of the left atrial posterior wall and perimitral area may considerably improve the efficacy of surgical treatment, which was demonstrated in significant decrease of AF recurrences during the whole period of follow-up.

Keywords: atrial fibrillation, cryoablation, left atrium isolation, open heart procedure

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Authors: Abhishek Pandey

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Ibuprofen and Acetaminophen is widely used as prescription & non-prescription medicine. Ibuprofen mainly used in the treatment of mild to moderate pain related to headache, migraine, postoperative condition and in the management of spondylitis, osteoarthritis and rheumatoid arthritis. Acetaminophen is used as an analgesic and antipyretic drug. Ibuprofen having high tendency of sticking to punches of tablet punching machine while Acetaminophen is not ordinarily compressible to tablet formulation because Acetaminophen crystals are very hard and brittle in nature and fracture very easily when compressed producing capping and laminating tablet defects therefore wet granulation method is used to make them compressible. The aim of study was to prepare Ibuprofen and Acetaminophen tablets by direct compression and top spray granulation technique. In this Investigation tablets were prepared by using directly compressible grade excipients. Dibasic calcium phosphate, lactose anhydrous (DCL21), microcrystalline cellulose (Avicel PH 101). In order to obtain best or optimized formulation, nine different formulations were generated among them batch F7, F8, F9 shows good results and within the acceptable limit. Formulation (F7) selected as optimize product on the basis of dissolution study. Furtherly, directly compressible granules of both drugs were prepared by using top spray granulation technique in fluidized bed processor equipment and compressed .In order to obtain best product process optimization was carried out by performing four trials in which various parameters like inlet air temperature, spray rate, peristaltic pump rpm, % LOD, properties of granules, blending time and hardness were optimized. Batch T3 coined as optimized batch on the basis physical & chemical evaluation. Finally formulations prepared by both techniques were compared.

Keywords: direct compression, top spray granulation, process optimization, blending time

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Authors: Ergin Kosa, Ali Göksenli

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Erosion and abrasion are wear mechanisms reducing the lifetime of machine elements like valves, pump and pipe systems. Both wear mechanisms are acting at the same time, causing a “Synergy” effect, which leads to a rapid damage of the surface. Different parameters are effective on erosive abrasive wear rate. In this study effect of particle impact angle on wear rate and wear mechanism of ductile and brittle materials was investigated. A new slurry pot was designed for experimental investigation. As abrasive particle, silica sand was used. Particle size was ranking between 200-500 µm. All tests were carried out in a sand-water mixture of 20% concentration for four hours. Impact velocities of the particles were 4,76 m/s. As ductile material steel St 37 with Brinell Hardness Number (BHN) of 245 and quenched St 37 with 510 BHN was used as brittle material. After wear tests, morphology of the eroded surfaces were investigated for better understanding of the wear mechanisms acting at different impact angles by using optical microscopy and Scanning Electron Microscope. The results indicated that wear rate of ductile material was higher than brittle material. Maximum wear was observed by ductile material at a particle impact angle of 300. On the contrary wear rate increased by brittle materials by an increase in impact angle and reached maximum value at 450. High amount of craters were detected after observation on ductile material surface Also plastic deformation zones were detected, which are typical failure modes for ductile materials. Craters formed by particles were deeper according to brittle material worn surface. Amount of craters decreased on brittle material surface. Microcracks around craters were detected which are typical failure modes of brittle materials. Deformation wear was the dominant wear mechanism on brittle material. At the end it is concluded that wear rate could not be directly related to impact angle of the hard particle due to the different responses of ductile and brittle materials.

Keywords: erosive wear, particle impact angle, silica sand, wear rate, ductile-brittle material

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Authors: Marco Naegele, Klaus Stoppel, Thomas Dekorsy

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Passively Q-switched microchip lasers enable the great potential for sophisticated LiDAR systems due to their compact overall system design, excellent beam quality, and scalable pulse energies. However, many near-infrared solid-state lasers show emitting wavelengths > 1000 nm, which are not compatible with state-of-the-art silicon detectors. Here we demonstrate a passively Q-switched microchip laser operating at 914 nm. The microchip laser consists of a 3 mm long Nd:YVO₄ crystal as a gain medium, while Cr⁴⁺:YAG with an initial transmission of 98% is used as a saturable absorber. Quasi-continuous pumping enables single pulse operation, and low duty cycles ensure low overall heat generation and power consumption. Thus, thermally induced instabilities are minimized, and operation without active cooling is possible while ambient temperature changes are compensated by adjustment of the pump laser current only. Single-emitter diode pumping at 808 nm leads to a compact overall system design and robust setup. Utilization of a microchip cavity approach ensures single-longitudinal mode operation with spectral bandwidths in the picometer regime and results in short laser pulses with pulse durations below 10 ns. Beam quality measurements reveal an almost diffraction-limited beam and enable conclusions concerning the thermal lens, which is essential to stabilize the plane-plane resonator. A 7% output coupler transmissivity is used to generate pulses with energies in the microjoule regime and peak powers of more than 600 W. Long-term pulse duration, pulse energy, central wavelength, and spectral bandwidth measurements emphasize the excellent system stability and facilitate the utilization of this laser in the context of a LiDAR system.

Keywords: diode-pumping, LiDAR system, microchip laser, Nd:YVO4 laser, passively Q-switched

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Authors: Sreto Boljevic

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In the absence of considerable investment in electricity generation, transmission and distribution network (DN) capacity, the demand for electrical energy will quickly strain the capacity of the existing electrical power network. With anticipated growth and proliferation of Electric vehicles (EVs) and Heat pump (HPs) identified the likelihood that the additional load from EV changing and the HPs operation will require capital investment in the DN. While an area-wide implementation of EVs and HPs will contribute to the decarbonization of the energy system, they represent new challenges for the existing low-voltage (LV) network. Distributed energy resources (DER), operating both as part of the DN and in the off-network mode, have been offered as a means to meet growing electricity demand while maintaining and ever-improving DN reliability, resiliency and power quality. DN planning has traditionally been done by forecasting future growth in demand and estimating peak load that the network should meet. However, new problems are arising. These problems are associated with a high degree of proliferation of EVs and HPs as load imposes on DN. In addition to that, the promotion of electricity generation from renewable energy sources (RES). High distributed generation (DG) penetration and a large increase in load proliferation at low-voltage DNs may have numerous impacts on DNs that create issues that include energy losses, voltage control, fault levels, reliability, resiliency and power quality. To mitigate negative impacts and at a same time enhance positive impacts regarding the new operational state of DN, CHP system integration can be seen as best action to postpone/reduce capital investment needed to facilitate promotion and maximize benefits of EVs, HPs and RES integration in low-voltage DN. The aim of this paper is to generate an algorithm by using an analytical approach. Algorithm implementation will provide a way for optimal placement of the CHP system in the DN in order to maximize the integration of RES and increase in proliferation of EVs and HPs.

Keywords: combined heat & power (CHP), distribution networks, EVs, HPs, RES

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Authors: Tatiana A. Pozdniakova, Maria A. P. Cechinel, Luciana P. Mazur, Rui A. R. Boaventura, Vitor J. P. Vilar.

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Two brown macroalgae, Laminaria hyperborea and Pelvetia canaliculata, were employed as natural cation exchangers in a fixed-bed column for Zn(II) removal from a galvanization wastewater. The column (4.8 cm internal diameter) was packed with 30-59 g of previously hydrated algae up to a bed height of 17-27 cm. The wastewater or eluent was percolated using a peristaltic pump at a flow rate of 10 mL/min. The effluent used in each experiment presented similar characteristics: pH of 6.7, 55 mg/L of chemical oxygen demand and about 300, 44, 186 and 244 mg/L of sodium, calcium, chloride and sulphate ions, respectively. The main difference was nitrate concentration: 20 mg/L for the effluent used with L. hyperborean and 341 mg/L for the effluent used with P. canaliculata. The inlet zinc concentration also differed slightly: 11.2 mg/L for L. hyperborean and 8.9 mg/L for P. canaliculata experiments. The breakthrough time was approximately 22.5 hours for both macroalgae, corresponding to a service capacity of 43 bed volumes. This indicates that 30 g of biomass is able to treat 13.5 L of the galvanization wastewater. The uptake capacities at the saturation point were similar to that obtained in batch studies (unpublished data) for both algae. After column exhaustion, desorption with 0.1 M HNO3 was performed. Desorption using 9 and 8 bed volumes of eluent achieved an efficiency of 100 and 91%, respectively for L. hyperborean and P. canaliculata. After elution with nitric acid, the column was regenerated using different strategies: i) convert all the binding sites in the sodium form, by passing a solution of 0.5 M NaCl, until achieve a final pH of 6.0; ii) passing only tap water in order to increase the solution pH inside the column until pH 3.0, and in this case the second sorption cycle was performed using protonated algae. In the first approach, in order to remove the excess of salt inside the column, distilled water was passed through the column, leading to the algae structure destruction and the column collapsed. Using the second approach, the algae remained intact during three consecutive sorption/desorption cycles without loss of performance.

Keywords: biosorption, zinc, galvanization wastewater, packed-bed column

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Authors: Maxim Glushenkov, Alexander Kronberg

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Isobaric expansion (IE) process is an alternative to conventional gas/vapor expansion accompanied by a pressure decrease typical of all state-of-the-art heat engines. The elimination of the expansion stage accompanied by useful work means that the most critical and expensive parts of ORC systems (turbine, screw expander, etc.) are also eliminated. In many cases, IE heat engines can be more efficient than conventional expansion machines. In addition, IE machines have a very simple, reliable, and inexpensive design. They can also perform all the known operations of existing heat engines and provide usable energy in a very convenient hydraulic or pneumatic form. This paper reports measurement made with the engine operating as a heat-to-shaft-power or electricity converter and a comparison of the experimental results to a thermodynamic model. Experiments were carried out at heat source temperature in the range 30–85 °C and heat sink temperature around 20 °C; refrigerant R134a was used as the engine working fluid. The pressure difference generated by the engine varied from 2.5 bar at the heat source temperature 40 °C to 23 bar at the heat source temperature 85 °C. Using a differential piston, the generated pressure was quadrupled to pump hydraulic oil through a hydraulic motor that generates shaft power and is connected to an alternator. At the frequency of about 0.5 Hz, the engine operates with useful powers up to 1 kW and an oil pumping flowrate of 7 L/min. Depending on the temperature of the heat source, the obtained efficiency was 3.5 – 6 %. This efficiency looks very high, considering such a low temperature difference (10 – 65 °C) and low power (< 1 kW). The engine’s observed performance is in good agreement with the predictions of the model. The results are very promising, showing that the engine is a simple and low-cost alternative to ORC plants and other known energy conversion systems, especially at low temperatures (< 100 °C) and low power range (< 500 kW) where other known technologies are not economic. Thus low-grade solar, geothermal energy, biomass combustion, and waste heat with a temperature above 30 °C can be involved into various energy conversion processes.

Keywords: isobaric expansion, low-grade heat, heat engine, renewable energy, waste heat recovery

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Authors: Jyoti Manandhar Shrestha, Saurab Raj Joshi, Maya Shrestha, Prashanna Shrestha, Kshitij Chaulagain

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Background: The widespread use of non-steroidal anti-inflammatory drugs has increased the incidence of ulcer and serious complications, such as perforation and bleeding. Although, the H2 receptor blockers and proton pump inhibitors decrease the acid secretion and promote healing of ulcer, their value in preventing relapse, recurrence, “acid rebound” after cessation of therapy and associated long term adverse effects limit their utility. So to minimize this, the herbal plant Aloe vera having anti-oxidant, anti-inflammatory, mucus secreting, cyto-protective and healing property is believed to cure the peptic ulcer. Objectives: To observe whether oral treatment with Aloe vera gel can prevent peptic ulcer. Indomethacin and ethanol were used to induce gastric ulcers. Thirty six albino rats of either sex were randomly allotted to six groups of six animals each. The negative control was pretreated with normal saline, the positive controls received ranitidine (20 mg/kg) and the test group received Aloe vera gel (300 mg/kg) orally for eight days. Then, after a 24 hour fast Indomethacin (20 mg/kg) or 80% ethanol (2ml) was administered orally to induce ulceration. At the end of the study, the rats were sacrificed, their stomachs opened, the ulcer index studied and tissues sent for histopathological examination. Results: It was observed that, in indomethacin treated group, the ulcer index in control group was 8.167 ± 1.72.In the Aloe vera pretreated animals, the ulcer index was 2.83 ± 1.72 and the standard ranitidine pretreated group ulcer index was 1.67 ± 1.36. In ethanol treated group, the ulcer index in control group was 7.5 ± 2.73. In the Aloe vera pretreated animals, the ulcer index was 2.67 ± 1.75 and the standard ranitidine pretreated group ulcer index was 1.33±1.21. Both ranitidine and Aloe vera gel significantly prevented stomach from gastric ulceration induced by indomethacin and ethanol. Conclusion: The results indicated that Aloe vera gel is effective against indomethacin and ethanol mediated gastric ulcer.

Keywords: Aloe vera gel, ethanol, indomethacin, peptic ulcer, ranitidine

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Authors: Devendra Gupta, S. P. Ambesh, P. K Singh

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Introduction: Minimally invasive coronary artery bypass grafting (MICABG) is a less invasive method of performing surgical revascularization. Minimally invasive direct coronary artery bypass (MIDCAB) provides many anesthetic challenges including one lung ventilation (OLV), managing myocardial ischemia, and pain. We present an early and midterm result of the use of this technique with OLV. Method: We enrolled 62 patients for analysis operated between 2008 and 2012. Patients were anesthetized and left endobronchial tube was placed. During the procedure left lung was isolated and one lung ventilation was maintained through right lung. Operation was performed utilizing off pump technique of coronary artery bypass grafting through a minimal invasive incision. Left internal mammary artery graft was done for single vessel disease and radial artery was utilized for other grafts if required. Postoperative ventilation was done with single lumen endotracheal tube. Median follow-up is 2.5 years (6 months to 4 years). Results: Median age was 58.5 years (41-77) and all were male. Single vessel disease was present in 36, double vessel in 24 and triple vessel disease in 2 patients. All the patients had normal left ventricular size and function. In 2 cases difficulty were encounter in placement of endobronchial tube. In 1 case cuff of endobronchial tube was ruptured during intubation. High airway pressure was developed on OLV in 1 case and surgery was accomplished with two lung anesthesia with low tidal volume. Mean postoperative ventilation time was 14.4 hour (11-22). There was no perioperative and 30 day mortality. Conversion to median sternotomy to complete the operation was done in 3.23% (2 out of 62 patients). One patient had acute myocardial infarction postoperatively and there were no deaths during follow-up. Conclusion: MICABG is a safe and effective method of revascularization with OLV in low risk candidates for coronary artery bypass grafting.

Keywords: MIDCABG, one lung ventilation, coronary artery bypass grafting, endobronchial tube

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Authors: Marinna Madrid, Nabiha Saklayen, Marinus Huber, Nicolas Vogel, Christos Boutopoulos, Michel Meunier, Eric Mazur

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Delivering material into cells is important for a diverse range of biological applications, including gene therapy, cellular engineering and imaging. We present a plasmonic substrate for delivering membrane-impermeable material into cells at high throughput and high efficiency while maintaining cell viability. The substrate fabrication is based on an affordable and fast colloidal self-assembly process. When illuminated with a femtosecond laser, the light interacts with the electrons at the surface of the metal substrate, creating localized surface plasmons that form bubbles via energy dissipation in the surrounding medium. These bubbles come into close contact with the cell membrane to form transient pores and enable entry of membrane-impermeable material via diffusion. We use fluorescence microscopy and flow cytometry to verify delivery of membrane-impermeable material into HeLa CCL-2 cells. We show delivery efficiency and cell viability data for a range of membrane-impermeable cargo, including dyes and biologically relevant material such as siRNA. We estimate the effective pore size by determining delivery efficiency for hard fluorescent spheres with diameters ranging from 20 nm to 2 um. To provide insight to the cell poration mechanism, we relate the poration data to pump-probe measurements of micro- and nano-bubble formation on the plasmonic substrate. Finally, we investigate substrate stability and reusability by using scanning electron microscopy (SEM) to inspect for damage on the substrate after laser treatment. SEM images show no visible damage. Our findings indicate that self-assembled plasmonic substrates are an affordable tool for high-throughput, high-efficiency delivery of material into mammalian cells.

Keywords: femtosecond laser, intracellular delivery, plasmonic, self-assembly

Procedia PDF Downloads 502

Authors: Snehal D. Ganjave, Hardik Dodia, Avinash V. Sunder, Swati Madhu, Pramod P. Wangikar

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Batch cultivation of recombinant bacteria in shake flasks results in low cell density due to nutrient depletion. Previous protocols on high cell density cultivation in shake flasks have relied mainly on controlled release mechanisms and extended cultivation protocols. In the present work, we report an optimized fed-batch process for high cell density cultivation of recombinant E. coli BL21(DE3) for protein production. A cybernetic model-based, multi-objective optimization strategy was implemented to obtain the optimum operating variables to achieve maximum biomass and minimized substrate feed rate. A syringe pump was used to feed a mixture of glycerol and yeast extract into the shake flask. Preliminary experiments were conducted with online monitoring of dissolved oxygen (DO) and offline measurements of biomass and glycerol to estimate the model parameters. Multi-objective optimization was performed to obtain the pareto front surface. The selected optimized recipe was tested for a range of proteins that show different extent soluble expression in E. coli. These included eYFP and LkADH, which are largely expressed in soluble fractions, CbFDH and GcanADH , which are partially soluble, and human PDGF, which forms inclusion bodies. The biomass concentrations achieved in 24 h were in the range 19.9-21.5 g/L, while the model predicted value was 19.44 g/L. The process was successfully reproduced in a standard laboratory shake flask without online monitoring of DO and pH. The optimized fed-batch process showed significant improvement in both the biomass and protein production of the tested recombinant proteins compared to batch cultivation. The proposed process will have significant implications in the routine cultivation of E. coli for various applications.

Keywords: cybernetic model, E. coli, high cell density cultivation, multi-objective optimization

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Authors: Hyun Chang Kim, Yong Hun Jung, Kyung Woon Jeung

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Background: From the viewpoint of cardiac pump theory, the area of the left ventricle (LV) subjected to compression increases as the LV lies closer to the sternum, possibly resulting in higher blood flow in patients with LV closer to the sternum. However, no study has evaluated LV position during cardiac arrest or its relationship with hemodynamic parameters during cardiopulmonary resuscitation (CPR). The objectives of this study were to determine whether the position of the LV relative to the anterior-posterior axis representing the direction of chest compression shifts during cardiac arrest and to examine the relationship between LV position and hemodynamic parameters during CPR. Methods: Subcostal view echocardiograms were obtained from 15 pigs with the transducer parallel to the long axis of the sternum before inducing ventricular fibrillation (VF) and during cardiac arrest. Computed tomography was performed in three pigs to objectively observe LV position during cardiac arrest. LV position parameters including the shortest distance between the anterior-posterior axis and the mid-point of the LV chamber (DAP-MidLV), the shortest distance between the anterior-posterior axis and the LV apex (DAP-Apex), and the area fraction of the LV located on the right side of the anterior-posterior axis (LVARight/LVATotal) were measured. Results: DAP-MidLV, DAP-Apex, and LVARight/LVATotal decreased progressively during untreated VF and basic life support (BLS), and then increased during advanced cardiovascular life support (ACLS). A repeated measures analysis of variance revealed significant time effects for these parameters. During BLS, the end-tidal carbon dioxide and systolic right atrial pressure were significantly correlated with the LV position parameters. During ACLS, systolic arterial pressure and systolic right atrial pressure were significantly correlated with DAP-MidLV and DAP-Apex. Conclusions: LV position changed significantly during cardiac arrest compared to the pre-arrest baseline. LV position during CPR had significant correlations with hemodynamic parameters.

Keywords: heart arrest, cardiopulmonary resuscitation, heart ventricle, hemodynamics

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Authors: Arefeh Hesaraki

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The application of photovoltaic-thermal hybrids (PVT), which delivers both electricity and heat simultaneously from the same system, has become more popular during the past few years. This study addresses techno-economic and environmental impacts assessment of photovoltaic/thermal systems combined with a ground-source heat pump (GSHP) for three single-family houses located in Stockholm, Sweden. Three case studies were: (1) A renovated building built in 1936, (2) A renovated building built in 1973, and (3) A new building built-in 2013. Two simulation programs of SimaPro 9.1 and IDA Indoor Climate and Energy 4.8 (IDA ICE) were applied to analyze environmental impacts and energy usage, respectively. The cost-effectiveness of the system was evaluated using net present value (NPV), internal rate of return (IRR), and discounted payback time (DPBT) methods. In addition to cost payback time, the studied PVT system was evaluated using the energy payback time (EPBT) method. EPBT presents the time that is needed for the installed system to generate the same amount of energy which was utilized during the whole lifecycle (fabrication, installation, transportation, and end-of-life) of the system itself. Energy calculation by IDA ICE showed that a 5 m² PVT was sufficient to create a balance between the maximum heat production and the domestic hot water consumption during the summer months for all three case studies. The techno-economic analysis revealed that combining a 5 m² PVT with GSHP in the second case study possess the smallest DPBT and the highest NPV and IRR among the three case studies. It means that DPBTs (IRR) were 10.8 years (6%), 12.6 years (4%), and 13.8 years (3%) for the second, first, and the third case study, respectively. Moreover, environmental assessment of embodied energy during cradle- to- grave life cycle of the studied PVT, including fabrication, delivery of energy and raw materials, manufacture process, installation, transportation, operation phase, and end of life, revealed approximately two years of EPBT in all cases.

Keywords: life-cycle cost, life-cycle assessment, photovoltaic/thermal, IDA ICE, net present value

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Authors: Abdul Murad Zainal Abidin, Azahar Mohd, Nor Idayu Arifin, Siti Nor Azila Khalid, Mohd Julzaha Zahari Mohamad Yusof

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A thermoelectric cooler (TEC) is an electronic component that uses ‘peltier’ effect to create a temperature difference by transferring heat between two electrical junctions of two different types of materials. TEC can also be used for heating by reversing the electric current flow and even power generation. A heat flow meter (HFM) is an equipment for measuring thermal conductivity of building materials. During the test, water is used as heat transfer medium to cool the HFM. The existing re-circulating cooler in the market is very costly, and the alternative is to use piped tap water to extract heat from HFM. However, the tap water temperature is insufficiently low to enable heat transfer to take place. The operating temperature for isothermal plates in the HFM is 40°C with the range of ±0.02°C. When the temperature exceeds the operating range, the HFM stops working, and the test cannot be conducted. The aim of the research is to develop a low-cost but energy-efficient TEC prototype that enables heat transfer without compromising the function of the HFM. The objectives of the research are a) to identify potential of TEC as a cooling device by evaluating its cooling rate and b) to determine the amount of water savings using TEC compared to normal tap water. Four (4) peltier sets were used, with two (2) sets used as pre-cooler. The cooling water is re-circulated from the reservoir into HFM using a water pump. The thermal conductivity readings, the water flow rate, and the power consumption were measured while the HFM was operating. The measured data has shown decrease in average cooling temperature difference (ΔTave) of 2.42°C and average cooling rate of 0.031°C/min. The water savings accrued from using the TEC is projected to be 8,332.8 litres/year with the application of water re-circulation. The results suggest the prototype has achieved required objectives. Further research will include comparing the cooling rate of TEC prototype against conventional tap water and to optimize its design and performance in terms of size and portability. The possible application of the prototype could also be expanded to portable storage for medicine and beverages.

Keywords: energy efficiency, thermoelectric cooling, pre-cooling device, heat flow meter, sustainable technology, thermal conductivity

Procedia PDF Downloads 132

Authors: A. Durgadevi, S. Pushpavanam

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For the past several decades, CO2 levels have been dramatically increasing in the atmosphere due to the man-made emissions such as fossil fuel-fired power plants. With the increase in CO2 emissions, CO2 concentration in the atmosphere has increased resulting in global warming. This shows the need to study different ways to capture the emitted CO2 directly from the exhausts of power plants or atmosphere. There are several ways to remove CO2, such as absorption into a liquid solvent, adsorption into a solid, cryogenic separation, permeation through membranes and photochemical conversion. In most industries, the absorption of CO2 in chemical solvents (in absorption towers) is used for CO2 capture. In these towers, the mass transfer along with chemical reactions take place between the gas and liquid phase. This helps in the separation of CO2 from other gases. It is important to understand these processes in detail. These flow patterns are difficult to maintain in large scale industrial absorbers. So to get accurate information controlled gas-liquid absorption experiments are carried out in milli-channels in this work under controlled atmosphere. The absorption experiments of CO2 in varying concentrations of sodium hydroxide solution are carried out in T-junction glass milli-channels with a circular cross section (inner diameter of 2mm). The gas and liquid flow rates are controlled by a mass flow controller (MFC) and a Harvard syringe pump respectively. The slug flow in the channel is recorded using a camera and the videos are analysed. The gas slug of pure CO2 is found to decrease in size along the length of the channel due to absorption of gas in the liquid. This is also captured with the model developed and the mass transfer characteristics are studied. The pressure drop across the channel is determined by sum of the pressure drops from the gas slugs and the liquid plugs. A dimensionless correlation for the mass transfer coefficient is developed in terms of Sherwood number and compared with the existing correlations in the literature. They are found to be in close agreement with each other. In this case, due to the presence of chemical reaction, the enhancement of mass transfer is obtained. This is quantified with the help of an enhancement factor.

Keywords: absorption, enhancement factor, mass transfer coefficient, Sherwood number

Procedia PDF Downloads 142

Authors: Lena Ernstgård, Aishwarya M. Dwivedi, Johan Lundström, Gunnar Johanson

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A simple inexpensive olfactometer was constructed to enable valid measures of detection threshold of low concentrations of vapours of chemicals. The delivery system consists of seven syringe pumps, each connected to a Tedlar bag containing a predefined concentration of the test chemical in the air. The seven pumps are connected to a 8-way mixing valve which in turn connects to a birhinal nose piece. Chemical vapor of known concentration is generated by injection of an appropriate amount of the test chemical into a Tedlar bag with a known volume of clean air. Complete vaporization is assured by gentle heating of the bag from the outside with a heat flow. The six test concentrations are obtained by adding different volumes from the starting bag to six new Tedlar bags with known volumes of clean air. One bag contains clean air only. Thus, six different test concentrations and clean air can easily be tested in series by shifting the valve to new positions. Initial in-line measurement with a photoionization detector showed that the delivery system quickly responded to a shift in valve position. Thus 90% of the desired concentration was reached within 15 seconds. The concentrations in the bags are verified daily by gas chromatography. The stability of the system in terms of chemical concentration is monitored in real time by means of a photo-ionization detector. To determine lateralization thresholds, an additional pump supplying clean air is added to the delivery system in a way so that the nostrils can be separately and interchangeably be exposed to clean air and test chemical. Odor and lateralization thresholds were determined for three aldehydes; acrolein, crotonaldehyde, and hexanal in 20 healthy naïve individuals. Aldehydes generally have a strong odour, and the selected aldehydes are also considered to be irritating to mucous membranes. The median odor thresholds of the three aldehydes were 0.017, 0.0008, and 0.097 ppm, respectively. No lateralization threshold could be identified for acrolein, whereas the medians for crotonaldehyde and hexanal were 0.003 and 0.39 ppm, respectively. In conclusion, we constructed a simple, inexpensive olfactometer that allows for stable and easily measurable concentrations of vapors of the test chemical. Our test with aldehydes demonstrates that the system produces valid detection among volunteers in terms of odour and lateralization thresholds.

Keywords: irritation, odour delivery, olfactometer, smell

Procedia PDF Downloads 189

Authors: Sreto Boljevic

Abstract:

Heating systems based on geothermal energy sources are becoming increasingly popular among commercial/community buildings as management of these buildings looks for a more efficient and environmentally friendly way to manage the heating system. The thermal energy supply of most European commercial/community buildings at present is provided mainly by energy extracted from natural gas. In order to reduce greenhouse gas emissions and achieve climate change targets set by the EU, restructuring in the area of thermal energy supply is essential. At present, heating and cooling account for approx... 50% of the EU primary energy supply. Due to its physical characteristics, thermal energy cannot be distributed or exchange over long distances, contrary to electricity and gas energy carriers. Compared to electricity and the gas sectors, heating remains a generally black box, with large unknowns to a researcher and policymaker. Ain literature number of documents address policies for promoting renewable energy technology to facilitate heating for residential/community/commercial buildings and assess the balance between heat supply and heat savings. Ground source heat pump (GSHP) technology has been an extremely attractive alternative to traditional electric and fossil fuel space heating equipment used to supply thermal energy for residential/community/commercial buildings. The main purpose of this paper is to create an algorithm using an analytical approach that could enable a feasibility study regarding the implementation of GSHP technology in community building with existing fossil-fueled heating systems. The main results obtained by the algorithm will enable building management and GSHP system designers to define the optimal size of the system regarding technical, environmental, and economic impacts of the system implementation, including payback period time. In addition, an algorithm is created to be utilized for a feasibility study for many different types of buildings. The algorithm is tested on a building that was built in 1930 and is used as a church located in Cork city. The heating of the building is currently provided by a 105kW gas boiler.

Keywords: GSHP, greenhouse gas emission, low-enthalpy, renewable energy

Procedia PDF Downloads 183