Search results for: enhanced oil recovery

Authors: Yixin Yan, Miao Yan, Irini Angelidaki, Ioannis Fotidis

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Ammonia, which derives from the degradation of urea and protein-substrates, is the major toxicant of the commercial anaerobic digestion reactors causing loses of up to 1/3 of their practical biogas production, which reflects directly on the overall revenue of the plants. The current experimental work is aiming to alleviate the ammonia inhibition in anaerobic digestion (AD) process by developing an innovative bioaugmentation method of ammonia tolerant methanogenic consortia. The ammonia tolerant consortia were cultured in batch reactors and immobilized together with biochar in agar (customized inocula). Three continuous stirred-tank reactors (CSTR), fed with the organic fraction of municipal solid waste at a hydraulic retention time of 15 days and operated at thermophilic (55°C) conditions were assessed. After an ammonia shock of 4 g NH4+-N L-1, the customized inocula were bioaugmented into the CSTR reactors to alleviate ammonia toxicity effect on AD process. Recovery rate of methane production and methanogenic activity will be assessed to evaluate the bioaugmentation performance, while 16s rRNA gene sequence will be used to reveal the difference of microbial community changes through bioaugmentation. At the microbial level, the microbial community structures of the four reactors will be analysed to find the mechanism of bioaugmentation. Changes in hydrogen formation potential will be used to predict direct interspecies electron transfer (DIET) between ammonia tolerant methanogens and syntrophic bacteria. This experimental work is expected to create bioaugmentation inocula that will be easy to obtain, transport, handled and bioaugment in AD reactors to efficiently alleviate the ammonia toxicity, without alternating any of the other operational parameters including the ammonia-rich feedstocks.

Keywords: artisanal fishing waste, acidogenesis, volatile fatty acids, pH, inoculum/substrate ratio

Procedia PDF Downloads 117

Authors: Homa Torabizadeh, Mohaddeseh Mikani

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Inulinase from Aspergillus niger was covalently immobilized on magnetic nanoparticles (MNPs/Fe₃O₄) covered with soy protein isolate (SPI/Fe₃O₄) functionalized by bovine serum albumin (BSA) nanoparticles. MNPs are promising enzyme carriers because they separate easily under external magnetic fields and have enhanced immobilized enzyme reusability. As MNPs aggregate simply, surface coating strategy was employed. SPI functionalized by BSA was a suitable candidate for nanomagnetite coating due to its superior biocompatibility and hydrophilicity. Fe₃O₄@SPI-BSA nanoparticles were synthesized as a novel carrier with narrow particle size distribution. Step by step fabrication monitoring of Fe₃O₄@SPI-BSA nanoparticles was performed using field emission scanning electron microscopy and dynamic light scattering. The results illustrated that nanomagnetite with the spherical morphology was well monodispersed with the diameter of about 35 nm. The average size of the SPI-BSA nanoparticles was 80 to 90 nm, and their zeta potential was around −34 mV. Finally, the mean diameter of fabricated Fe₃O₄@SPI-BSA NPs was less than 120 nm. Inulinase enzyme from Aspergillus niger was covalently immobilized through gluteraldehyde on Fe₃O₄@SPI-BSA nanoparticles successfully. Fourier transform infrared spectra and field emission scanning electron microscopy images provided sufficient proof for the enzyme immobilization on the nanoparticles with 80% enzyme loading.

Keywords: high fructose syrup, inulinase immobilization, functionalized magnetic nanoparticles, soy protein isolate

Procedia PDF Downloads 293

Authors: Adam Y. Sulaiman, Donal F. Cotter, Ming J. Huang, Neil J. Hewitt

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Suitable low global warming potential (GWP) refrigerants that conform to F-gas regulations are required to extend the operational envelope of high-temperature heat pumps (HTHPs) used for industrial waste heat recovery processes. The thermophysical properties and characteristics of these working fluids need to be assessed to provide a comprehensive understanding of operational effectiveness in HTHP applications. This paper presents the results of a theoretical simulation to investigate a range of low-GWP refrigerants and their suitability to supersede refrigerants HFC-245fa and HFC-365mfc. A steady-state thermodynamic model of a single-stage HTHP with an internal heat exchanger (IHX) was developed to assess system cycle characteristics at temperature ranges between 50 to 80 °C heat source and 90 to 150 °C heat sink. A practical approach to maximize the operational efficiency was examined to determine the effects of regulating minimum superheat within the process and subsequent influence on energetic and exergetic efficiencies. A comprehensive map of minimum superheat across the HTHP operating variables were used to assess specific tipping points in performance at 30 and 70 K temperature lifts. Based on initial results, the refrigerants HCFO-1233zd(E) and HFO-1336mzz(Z) were found to be closely aligned matches for refrigerants HFC-245fa and HFC-365mfc. The overall results show effective performance for HCFO-1233zd(E) occurs between 5-7 K minimum superheat, and HFO-1336mzz(Z) between 18-21 K dependant on temperature lift. This work provides a method to optimize refrigerant selection based on operational indicators to maximize overall HTHPs system performance.

Keywords: high-temperature heat pump, minimum superheat, energy & exergy efficiency, low GWP refrigerants

Procedia PDF Downloads 163

Authors: Shabnam Alizadeh, Hatice Dumanoglu

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Plant tissue culture is a substantial plant propagation technique for mass clonal production throughout the year, regardless of time in fruit species. However, the rooting achievement must be enhanced in the difficult-to-root genotypes. Classical auxin applications in clonal propagation of these genotypes are inadequate to solve the rooting problem. Nanoparticles having different physical and chemical properties from bulk material could enhance the rooting success of controlled release of these substances when loaded with auxin due to their ability to reach the active substance up to the target cells as a carrier system.The purpose of this study is to investigate the effects of zinc oxide nanoparticles loaded with indole-3-acetic acid (IAA-nZnO) and indole-3-butyric acid (IBA-nZnO) on in vitro rooting of microcuttings in a difficult-to-root apple genotype (Malus domestica Borkh.). Rooting treatments consisted of IBA or IAA at concentrations of 0.5, 1.0, 2.0, 3.0 mg/L; nZnO, IAA-nZnO and IBA-nZnO at doses of 0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 mg/L were used. All components were added to the Murashige and Skoog (MS) basal medium at strength ½ with 2% sucrose and 0.7% agar before autoclaving. In the study, no rooting occurred in control and nZnO applications. Especially, 1.0 mg/L and 2.0 mg/L IBA-nZnO nanoparticle applications (containing 0.5 mg/L and 0.9 mg/L IBA), respectively with rooting rates of 40.3% and 70.4%, rooting levels of 2.0±0.4 and 2.3±0.4, 2.6±0.7 and 2.5±0.6 average root numbers and 20.4±1.6 mm and 20.2±3.4 mm average root lengths put forward as effective applications.

Keywords: Auxin, Malus, nanotechnology, zinc oxide nanoparticles

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Authors: Bilge Bozdogan, Selda T. Sendogdular, Levent Sendogdular

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We report a technique to control chain conformation during the plasticization process to achieve homogeneous and stable thin films, which allows to reduce post-process annealing times along with enhanced properties like controlled irreversible adsorbed layer (Guiselin brushes) formation. In this study, spin coating temperature was considered as a parameter; hence, all equipment, including the spin coater, substrate, vials, and the solution, was kept inside the same heated fume hood where solution was spin-coated after the temperature was stabilized at a desired value. AFM and SEM results revealed severe difference for solid and air interface between ambient and temperature-controlled samples, which suggest that enthalpic contribution dynamically helps to control film stability in a way where chain entanglements and conformational restrictions are avoided before film growing and allowing to control grafting density through spin coating temperature. The adsorbed layer was also characterized with SEM and Raman-spectroscopy technique right after seeding the adsorbed layer with gold nanoparticles. Stabilized gold nanoparticles and their surface distribution manifest the existence of a controllable polymer brush structure. Acknowledgments: This study was funded by Erciyes University Scientific Research Projects (BAP) Funding(Project ID:10058)

Keywords: chain stability, Guiselin brushes, polymer thin film, spin coating temperature

Procedia PDF Downloads 207

Authors: Yeon Ho Je

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A novel recombinant baculovirus, NeuroBactrus, was constructed to develop an improved baculovirus insecticide with additional beneficial properties, such as a higher insecticidal activity and improved recovery, compared to wild-type baculovirus. For the construction of NeuroBactrus, the Bacillus thuringiensis crystal protein gene (here termed cry1-5) was introduced into the Autographa californica nucleopolyhedrovirus (AcMNPV) genome by fusion of the polyhedrin–cry1-5–polyhedrin genes under the control of the polyhedrin promoter. In the opposite direction, an insect-specific neurotoxin gene, AaIT, from Androctonus australis was introduced under the control of an early promoter from Cotesia plutellae bracovirus by fusion of a partial fragment of orf603. The polyhedrin–Cry1-5–polyhedrin fusion protein expressed by the NeuroBactrus was not only occluded into the polyhedra, but it was also activated by treatment with trypsin, resulting in an_65-kDa active toxin. In addition, quantitative PCR revealed that the neurotoxin was expressed from the early phase of infection. NeuroBactrus showed a high level of insecticidal activity against Plutella xylostella larvae and a significant reduction in the median lethal time against Spodoptera exigua larvae compared to those of wild-type AcMNPV. Rerecombinant mutants derived from NeuroBactrus in which AaIT and/or cry1-5 were deleted were generated by serial passages in vitro. Expression of the foreign proteins (B. thuringiensis toxin and AaIT) was continuously reduced during the serial passage of the NeuroBactrus. Moreover, polyhedra collected from S. exigua larvae infected with the serially passaged NeuroBactrus showed insecticidal activity similar to that of wild-type AcMNPV. These results suggested that NeuroBactrus could be recovered to wild-type AcMNPV through serial passaging.

Keywords: baculovirus, insecticide, neurotoxin, neurobactrus

Procedia PDF Downloads 314

Authors: Ueda Honoka, Yasuo Hasegawa, Fumihiro Nishimura, Jae-Ho Kim, Susumu Yonezawa

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Aqueous peroxotitanium acid solution prepared from the TiO₂ fluorinated by F₂ gas was used for the TiO₂ coating on glass fibrous filters in this study. The coating of TiO₂ on the surface of glass fibers was carried out at 120℃ and for 15 min ~ 24 h with aqueous peroxotitanium acid solution using a hydrothermal synthesis autoclave reactor. The morphology TiO₂ coating layer was largely dependent on the reaction time, as shown in the results of scanning electron microscopy and energy dispersive X-ray spectroscopy. Increasing the reaction times, the TiO₂ layer on the glass expanded uniformly. Moreover, the surface fluorination of glass fibers can promote the formation of the TiO₂ layer on the surface. The photocatalytic activity of prepared titania-coated glass fibrous filters was investigated by both the degradation test of methylene blue (MB) and the decomposition test of gaseous acetaldehyde. The MB decomposition ratio with fluorinated samples was about 95% for 30 min of UV irradiation time, and it was much higher than that (70%) with the untreated thing. The decomposition ratio (50%) of gaseous acetaldehyde with fluorinated samples was also higher than that (30%) with the untreated thing. Consequently, photocatalytic activity is enhanced by surface fluorination.

Keywords: aqueous peroxotitanium acid solution, titania-coated glass fibrous filters, photocatalytic activity, surface fluorination

Procedia PDF Downloads 82

Authors: Jana Daher, Ammar Olabi, Elie-Jacques Fares, Samer Kharrroubi, Tarek Gherbal

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It has been previously suggested that the perception and acceptability of fluids significantly varies between exercise and non-exercise situations. The study investigates the influence of different types of sports on the taste perception and acceptability of a commercial sports drink. A sample of Gatorade – red orange flavor was evaluated pre and post exercise by 34 male university athletes (20 weightlifters, 14 runners) recruited from the American University of Beirut. Urine samples were collected from the participants to test for hydration. Sensory testing examined the change in the intensity of sweetness, saltiness, sourness, and the thirst-quenching ability of the drink as well as its acceptability with respect to the type of sport practiced. Results indicated that the acceptability of the drink increased as the hydration status of the athletes decreased (p<0.01). No significant change was found in the perception of the sensory attributes between exercise and non-exercise conditions. However, there were significant differences between the two sports groups in the ratings of the thirst-quenching ability of the drink where runners’ ratings increased after exercise while weightlifters’ ratings decreased after exercise (p<0.01). These findings suggest that exercise has a larger effect on the acceptability and overall liking of the beverage compared to other sensory attributes. An enhanced liking of the beverage is key for optimal replenishment of lost fluids and electrolytes after exercise.

Keywords: hedonic, liking, sweetness, thirst-quenching

Procedia PDF Downloads 126

Authors: Xi Quan Cheng, Yan Chao Xu, Xu Jiang, Lu Shao, Cher Hon Lau

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A hydrophilic thin-film-composite (TFC) nanofiltration (NF) membrane has been developed through the interfacial polymerization (IP) of amino-functional polyethylene glycol (PEG) and trimesoyl chloride. The selective layer is formed on a polyethersulfone (PES) support that is characterized using FTIR, XPS and SEM, and is dependent on monomer immersion duration, and the concentration of monomers and additives. The higher hydrophilicity alongside the larger pore size of the PEG-based selective layer is the key to a high water flux of 66.0 L m-2 h-1 at 5.0 bar. With mean pore radius of 0.42 nm and narrow pore size distribution, the MgSO4 rejections of the PEG based PA TFC NF membranes can reach up to 80.2 %. The hydrophilic PEG based membranes shows positive charged since the isoelectric points range from pH=8.9 to pH=9.1 and the rejection rates for different salts of the novel membranes are in the order of R(MgCl2)>R(MgSO4)>R(NaCl)>R(Na2SO4). The pore sizes and water permeability of these membranes are tailored by varying the molecular weight and molecular architecture of amino-functional PEG. Due to the unique structure of the selective layer of the PEG based membranes consisting of saturated aliphatic construction unit (CH2-CH2-O), the membranes demonstrate dual resistance to fouling and chlorine. The membranes maintain good salt rejections and high water flux of PEG based membranes after treatment by 2000 ppm NaClO for 24 hours. Interestingly, the PEG based membranes exhibit excellent fouling resistance with a water flux recovery of 90.2 % using BSA as a model molecule. More importantly, the hydrophilic PEG based NF membranes have been exploited to separate several water soluble antibiotics (such as tobramycin, an aminoglycoside antibiotic applied in the treatment of various types of bacterial infections), showing excellent performance in concentration or removal of antibioics.

Keywords: nanofiltration, antibiotic separation, hydrophilic membrane, high flux

Procedia PDF Downloads 315

Authors: Aliaa M. S. Salem, Soliman I. El-Hout, Amira Gaber, Hassan Nageh

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Nowadays, the development of poisonous gas detectors is considered to be an urgent matter to secure human health and the environment from poisonous gases, in view of the fact that even a minimal amount of poisonous gas can be fatal. Of these concerns, various inorganic or organic sensing materials have been used. Among these are conducting polymers, have been used as the active material in the gassensorsdue to their low-cost,easy-controllable molding, good electrochemical properties including facile fabrication process, inherent physical properties, biocompatibility, and optical properties. Moreover, conducting polymer-based chemical sensors have an amazing advantage compared to the conventional one as structural diversity, facile functionalization, room temperature operation, and easy fabrication. However, the low selectivity and conductivity of conducting polymers motivated the doping of it with varied materials, especially graphene, to enhance the gas-sensing performance under ambient conditions. There were a number of approaches proposed for producing polymer/ graphene nanocomposites, including template-free self-assembly, hard physical template-guided synthesis, chemical, electrochemical, and electrospinning...etc. In this work, we aim to prepare a novel gas sensordepending on Electrospun nanofibers of conducting polymer/RGO composite that is the effective and efficient expectation of poisonous gases like ammonia, in different application areas such as environmental gas analysis, chemical-,automotive- and medical industries. Moreover, our ultimate objective is to maximize the sensing performance of the prepared sensor and to check its recovery properties.

Keywords: electro spinning process, conducting polymer, polyaniline, polypyrrole, polythiophene, graphene oxide, reduced graphene oxide, functionalized reduced graphene oxide, spin coating technique, gas sensors

Procedia PDF Downloads 177

Authors: Haoshui Yu, Donghoi Kim, Truls Gundersen

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Low-temperature waste heat is abundant in the process industries, and large amounts of Liquefied Natural Gas (LNG) cold energy are discarded without being recovered properly in LNG terminals. Power generation is an effective way to utilize low-temperature waste heat and LNG cold energy simultaneously. Organic Rankine Cycles (ORCs) and CO₂ power cycles are promising technologies to convert low-temperature waste heat and LNG cold energy into electricity. If waste heat and LNG cold energy are utilized simultaneously in one system, the performance may outperform separate systems utilizing low-temperature waste heat and LNG cold energy, respectively. Low-temperature waste heat acts as the heat source and LNG regasification acts as the heat sink in the combined system. Due to the large temperature difference between the heat source and the heat sink, cascaded power cycle configurations are proposed in this paper. Cascaded power cycles can improve the energy efficiency of the system considerably. The cycle operating at a higher temperature to recover waste heat is called top cycle and the cycle operating at a lower temperature to utilize LNG cold energy is called bottom cycle in this study. The top cycle condensation heat is used as the heat source in the bottom cycle. The top cycle can be an ORC, transcritical CO₂ (tCO₂) cycle or supercritical CO₂ (sCO₂) cycle, while the bottom cycle only can be an ORC due to the low-temperature range of the bottom cycle. However, the thermodynamic path of the tCO₂ cycle and sCO₂ cycle are different from that of an ORC. The tCO₂ cycle and the sCO₂ cycle perform better than an ORC for sensible waste heat recovery due to a better temperature match with the waste heat source. Different combinations of the tCO₂ cycle, sCO₂ cycle and ORC are compared to screen the best configurations of the cascaded power cycles. The influence of the working fluid and the operating conditions are also investigated in this study. Each configuration is modeled and optimized in Aspen HYSYS. The results show that cascaded tCO₂/ORC performs better compared with cascaded ORC/ORC and cascaded sCO₂/ORC for the case study.

Keywords: LNG cold energy, low-temperature waste heat, organic Rankine cycle, supercritical CO₂ cycle, transcritical CO₂ cycle

Procedia PDF Downloads 252

Authors: Maria Luiza D. Ramiento, Maria Lissette D. Lucas

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Electricity is said to serve as the backbone of modern technology. Considering this, electricity consumption has dynamically grown due to the continuous demand. An alternative producer of energy concerning electricity must therefore be given focus. Microbial fuel cell wholly characterizes a new method of renewable energy recovery: the direct conversion of organic matter to electricity using bacteria. Electricity is produced as fuel or new food is given to the bacteria. The study concentrated in determining the feasibility of electricity production from local benthic zones. Microbial fuel cells were constructed to harvest the possible electricity and to test the presence of electricity producing microorganisms. Soil samples were gathered from Calumpang River, Palawan Mangrove Forest, Rosario River and Batangas Port. Eleven modules were constructed for the different trials of the soil samples. These modules were made of cathode and anode chambers connected by a salt bridge. For 85 days, the harvested voltage was measured daily. No parameter is added for the first 24 days. For the next 61 days, acetic acid was included in the first and second trials of the modules. Each of the trials of the soil samples gave a positive result in electricity production.There were electricity producing microbes in local benthic zones. It is observed that the higher the organic content of the soil sample, the higher the electricity harvested from it. It is recommended to identify the specific species of the electricity-producing microorganism present in the local benthic zone. Complement experiments are encouraged like determining the kind of soil particles to test its effect on the amount electricity that can be harvested. To pursue the development of microbial fuel cells by building a closed circuit in it is also suggested.

Keywords: microbial fuel cell, benthic zone, electricity, reduction-oxidation reaction, bacteria

Procedia PDF Downloads 393

Authors: M. M. Hefnawy, A. M. A. Homoda, M. A. Abounassif, A. M. Alanazia, A. Al-Majed, Gamal A. E. Mostafa

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PVC membrane sensors using different approach e.g. ion-pair, ionophore, and Schiff-base has been used as testing membrane sensor. Analytical applications of membrane sensors for direct measurement of variety of different ions in complex biological and environmental sample are reported. The most important step of such PVC membrane sensor is the sensing active material. The potentiometric sensors have some outstanding advantages including simple design, operation, wide linear dynamic range, relative fast response time, and rotational selectivity. The analytical applications of these techniques to pharmaceutical compounds in dosage forms are also discussed. The construction and electrochemical response characteristics of Poly (vinyl chloride) membrane sensors for moxifloxacin HCl (MOX) are described. The sensing membranes incorporate ion association complexes of moxifloxacin cation and sodium tetraphenyl borate (NaTPB) (sensor 1), phosphomolybdic acid (PMA) (sensor 2) or phosphotungstic acid (PTA) (sensor 3) as electroactive materials. The sensors display a fast, stable and near-Nernstian response over a relative wide moxifloxacin concentration range (1 ×10-2-4.0×10-6, 1 × 10-2-5.0×10-6, 1 × 10-2-5.0×10-6 M), with detection limits of 3×10-6, 4×10-6 and 4.0×10-6 M for sensor 1, 2 and 3, respectively over a pH range of 6.0-9.0. The sensors show good discrimination of moxifloxacin from several inorganic and organic compounds. The direct determination of 400 µg/ml of moxifloxacin show an average recovery of 98.5, 99.1 and 98.6 % and a mean relative standard deviation of 1.8, 1.6 and 1.8% for sensors 1, 2, and 3 respectively. The proposed sensors have been applied for direct determination of moxifloxacin in some pharmaceutical preparations. The results obtained by determination of moxifloxacin in tablets using the proposed sensors are comparable favorably with those obtained using the US Pharmacopeia method. The sensors have been used as indicator electrodes for potentiometric titration of moxifloxacin.

Keywords: potentiometry, PVC, membrane sensors, ion-pair, ionophore, schiff-base, moxifloxacin HCl, sodium tetraphenyl borate, phosphomolybdic acid, phosphotungstic acid

Procedia PDF Downloads 433

Authors: Francesca Favero, Despina Learmonth

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Carbohydrate addiction is said to be the sustained dependence on hyperpalatable foods rich in carbohydrates and sugar. This addiction manifests in increased consumption of carbohydrates through binging: a behaviour typically associated with eating disorders. There is a lack of consensus amongst relevant experts as to whether carbohydrates are physiologically or psychologically addictive. With an increased focus on carbohydrate addiction, an outpatient treatment programme, HELP, has been established in Cape Town, South Africa, to specifically address this issue. This research aimed to explore, pre-and post-intervention, the possible presence of, and subsequent shifts in, the maintaining mechanisms identified in the transdiagnostic model for eating disorders. However, the potential for the emergence of other perpetuating factors was not discounted and the nature of the analysis allowed for this possibility. Eight women between the ages of twenty-two and fifty, who had completed the outpatient treatment programme in the last six months, were interviewed. They were asked to speak retrospectively about their personal difficulties, eating and food, and their experience of the treatment. Thematic analysis was employed to identify themes arising from the data. Five themes congruent with the transdiagnostic model’s factors emerged: over-evaluation of weight and shape, core low self-esteem, interpersonal difficulties, clinical perfectionism and mood intolerance. A variety of sub-themes, elaborating upon the various ways in which the disordered eating was maintained, also emerged from the data. Shifts in these maintaining mechanisms were identified. Although not necessarily indicative of recovery, the results suggest that the outpatient HELP programme had a positive overall influence on the participants; and that the transdiagnostic model may be useful in understanding and guiding the treatment of clients who engage in this type of treatment programme.

Keywords: eating disorders, binge eating disorder, carbohydrate addiction, transdiagnostic model, maintaining mechanisms, thematic analysis, outpatient treatment

Procedia PDF Downloads 315

Authors: Olga A. Krysiak, Grzegorz Cichowicz, Wojciech Hyk, Michal Cyranski, Jan Augustynski

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Metal oxides are known electrocatalyst in water oxidation reaction. Due to the fact that it is desirable for efficient oxygen evolution catalyst to contain numerous redox-active metal ions to guard four electron water oxidation reaction, mixed metal oxides exhibit enhanced catalytic activity towards oxygen evolution reaction compared to single metal oxide systems. On the surface of fluorine doped tin oxide coated glass slide (FTO) deposited (doctor blade technique) mixed metal oxide layer composed of nickel, iron, and chromium. Oxide coating was acquired by heat treatment of the aqueous precursors' solutions of the corresponding salts. As-prepared electrodes were photosensitive and acted as an efficient oxygen evolution catalyst. Our results showed that obtained by this method electrodes can be activated which leads to achieving of higher current densities. The recorded current and photocurrent associated with oxygen evolution process were at least two orders of magnitude higher in the presence of oxide layer compared to bare FTO electrode. The overpotential of the process is low (ca. 0,2 V). We have also checked the activity of the catalyst at different known photoanodes used in sun-driven water splitting. Herein, we demonstrate that we were able to achieve efficient oxygen evolution catalysts using relatively cheap precursor consisting of earth abundant metals and simple method of preparation.

Keywords: chromium, electrocatalysis, iron, metal oxides, nickel, oxygen evolution

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Authors: Reza Rezaeipour Honarmandzad

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This paper introduces an aircraft cable fault detection and location method in light of TFDR keeping in mind the end goal to recognize the intermittent faults adequately and to adapt to the serial and after-connector issues being hard to be distinguished in time domain reflection. In this strategy, the correlation function of reflected and reference signal is used to recognize and find the airplane fault as per the qualities of reflected and reference signal in time-frequency domain, so the hit rate of distinguishing and finding intermittent faults can be enhanced adequately. In the work process, the reflected signal is interfered by the noise and false caution happens frequently, so the threshold de-noising technique in light of wavelet decomposition is used to diminish the noise interference and lessen the shortcoming alert rate. At that point the time-frequency cross connection capacity of the reference signal and the reflected signal based on Wigner-Ville appropriation is figured so as to find the issue position. Finally, LabVIEW is connected to execute operation and control interface, the primary capacity of which is to connect and control MATLAB and LABSQL. Using the solid computing capacity and the bottomless capacity library of MATLAB, the signal processing turn to be effortlessly acknowledged, in addition LabVIEW help the framework to be more dependable and upgraded effectively.

Keywords: aircraft cable, fault location, TFDR, LabVIEW

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Authors: Popy Bora, L. C. Bora, A. Bhattacharya, Sehnaz S. Ahmed

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Microbial bioagents, viz., Pseudomonas fluorescens, Bacillus subtilis, and Trichoderma viride were assessed for their ability to suppress grey blight caused by Pestalotiopsis theae, a major disease of tea crop in Assam. The expression of defense-related phytochemicals due to the application of these bioagents was also evaluated. The individual bioagents, as well as their combinations, were screened for their bioefficacy against P. theae in vitro using nutrient agar (NA) as basal medium. The treatment comprising a combination of the three bioagents, P. fluorescens, B. subtilis, and T. viride showed significantly the highest inhibition against the pathogen. Bioformulation of effective bioagent combinations was further evaluated under field condition, where significantly highest reduction of grey blight (90.30%), as well as the highest increase in the green leaf yield (10.52q/ha), was recorded due to application of the bioformulation containing the three bioagents. The application of the three bioformulation also recorded an enhanced level of caffeine (4.15%) and polyphenols (22.87%). A significant increase in the enzymatic activity of phenylalanine ammonia-lyase, peroxidase and polyphenol oxidase were recorded in the plants treated with the microbial bioformulation of the three bioagents. The present investigation indicates the role of microbial agents in suppressing disease, inducing plant defense response, as well as improving the quality of tea.

Keywords: enzymatic activity, grey blight, microbial bioagents, Pestalotiopsis theae, phytochemicals, plant defense, tea

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Authors: Atish Bagchi, Siva Chandrasekaran

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Background: According to World Bank national accounts data, the estimated global manufacturing value-added output in 2020 was 13.74 trillion USD. These manufacturing processes are monitored, modelled, and controlled by advanced, real-time, computer-based systems, e.g., Industrial IoT, PLC, SCADA, etc. These systems measure and manipulate a set of physical variables, e.g., temperature, pressure, etc. Despite the use of IoT, SCADA etc., in manufacturing, studies suggest that unplanned downtime leads to economic losses of approximately 864 billion USD each year. Therefore, real-time, accurate detection, classification and prediction of machine behaviour are needed to minimise financial losses. Although vast literature exists on time-series data processing using machine learning, the challenges faced by the industries that lead to unplanned downtimes are: The current algorithms do not efficiently handle the high-volume streaming data from industrial IoTsensors and were tested on static and simulated datasets. While the existing algorithms can detect significant 'point' outliers, most do not handle contextual outliers (e.g., values within normal range but happening at an unexpected time of day) or subtle changes in machine behaviour. Machines are revamped periodically as part of planned maintenance programmes, which change the assumptions on which original AI models were created and trained. Aim: This research study aims to deliver a Graph Neural Network(GNN)based hybrid forecasting model that interfaces with the real-time machine control systemand can detect, predict machine behaviour and behavioural changes (anomalies) in real-time. This research will help manufacturing industries and utilities, e.g., water, electricity etc., reduce unplanned downtimes and consequential financial losses. Method: The data stored within a process control system, e.g., Industrial-IoT, Data Historian, is generally sampled during data acquisition from the sensor (source) and whenpersistingin the Data Historian to optimise storage and query performance. The sampling may inadvertently discard values that might contain subtle aspects of behavioural changes in machines. This research proposed a hybrid forecasting and classification model which combines the expressive and extrapolation capability of GNN enhanced with the estimates of entropy and spectral changes in the sampled data and additional temporal contexts to reconstruct the likely temporal trajectory of machine behavioural changes. The proposed real-time model belongs to the Deep Learning category of machine learning and interfaces with the sensors directly or through 'Process Data Historian', SCADA etc., to perform forecasting and classification tasks. Results: The model was interfaced with a Data Historianholding time-series data from 4flow sensors within a water treatment plantfor45 days. The recorded sampling interval for a sensor varied from 10 sec to 30 min. Approximately 65% of the available data was used for training the model, 20% for validation, and the rest for testing. The model identified the anomalies within the water treatment plant and predicted the plant's performance. These results were compared with the data reported by the plant SCADA-Historian system and the official data reported by the plant authorities. The model's accuracy was much higher (20%) than that reported by the SCADA-Historian system and matched the validated results declared by the plant auditors. Conclusions: The research demonstrates that a hybrid GNN based approach enhanced with entropy calculation and spectral information can effectively detect and predict a machine's behavioural changes. The model can interface with a plant's 'process control system' in real-time to perform forecasting and classification tasks to aid the asset management engineers to operate their machines more efficiently and reduce unplanned downtimes. A series of trialsare planned for this model in the future in other manufacturing industries.

Keywords: GNN, Entropy, anomaly detection, industrial time-series, AI, IoT, Industry 4.0, Machine Learning

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Authors: Yongyu Duo, Xiaogang Liu, Qingrui Yue

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The anchor plays a critical role in the utilization of the tensile strength of carbon fiber-reinforced polymer (CFRP) plate when it is applied for the prestressed retrofitted and cable structures. In this paper, the anchor behavior of planar clamping anchor (PCA) under different interface treatment forms and normal pressures was investigated by the uniaxial static tensile test. Two interface treatment forms were adopted, including pure friction and the coupling action of friction and bonding. The results indicated that the load-bearing capacity of PCA could be obviously improved by the coupling action of friction and bonding compared with the action of pure friction. Under the normal pressure of 11 MPa, 22 MPa, and 33 MPa, the load-bearing capacity of PCA was enhanced by 164.61%, 68.40%, and 52.78%, respectively, and the tensile strength of the CFRP plate was fully exploited when the normal pressure reached 44 MPa. In addition, the experimental coefficient of static friction between the galling CFRP plate and a sandblasted steel plate was in the range of 0.28-0.30, corresponding to various normal pressure. Moreover, the failure mode was determined by the interface treatment form and normal pressure. The research in this paper has important guiding significance to optimize the design of the mechanical clamping anchor, contributing to promoting the application of CFRP plate in reinforcement and cable structure.

Keywords: PCA, CFRP plate, interface treatment form, normal pressure, friction, coupling action

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Authors: Nirmal Kumar Verma, Pallavi Jha

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Generation of the electromagnetic radiation oscillating at the frequencies in the terahertz range by propagation of two-color laser pulses in plasma is an active area of research due to its potential applications in various areas, including security screening, material characterization, and spectroscopic techniques. Due to nonionizing nature and the ability to penetrate several millimeters, THz radiation is suitable for diagnosis of cancerous cells. Traditional THz emitters like optically active crystals, when irradiated with high power laser radiation, are subject to material breakdown and hence low conversion efficiencies. This problem is not encountered in laser-plasma based THz radiation sources. The present paper is devoted to the study of the enhanced electromagnetic radiation generation by propagation of two-color, linearly polarized laser pulses through the magnetized plasma. The two lasers pulse orthogonally polarized are co-propagating along the same direction. The direction of the external magnetic field is such that one of the two laser pulses propagates in the ordinary mode, while the other pulse propagates in the extraordinary mode through the homogeneous plasma. A transverse electromagnetic wave with frequency in the THz range is generated due to the presence of the static magnetic field. It is observed that larger amplitude terahertz can be generated by mixing of ordinary and extraordinary modes of two-color laser pulses as compared with a single laser pulse propagating in the extraordinary mode.

Keywords: two-color laser pulses, electromagnetic radiation, magnetized plasma, ordinary and extraordinary modes

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Authors: Ashutosh Kumar, Irene M. C. Lo

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Ever since the discovery of TiO2 for decomposition of cyanide in water, it has been investigated extensively for the photocatalytic degradation of environmental pollutants, and became the most practical and prevalent photocatalyst. The superiority of TiO2 is due to its chemical and biological inertness, nontoxicity, strong oxidizing power and cost-effectiveness. However, during degradation of pollutants in wastewater, it suffers from problems, such as (a) separation after use, and (b) its poor photocatalytic performance under visible light irradiation (~45% of the solar spectrum). In order to bridge the research gaps, N-TiO2@SiO2@Fe3O4 nanophotocatalysts of average size 19 nm and effective surface area 47 m2 gm-1 were synthesized using sol-gel method. The characterization was performed using BET, TEM-EDX, VSM and XRD. The performance was improved by considering different factors involved during the synthesis, such as calcination temperature, amount of Fe3O4 nanoparticles used and amount of urea used for N-doping. The final nanophotocatalyst was calcined at 500 °C which was able to degrade 94% of the ibuprofen within 5 h of irradiation time. Under the influence of ~200 mT electromagnetic field, 95% nanophotocatalysts separation efficiency was achieved within 20-25 min. Moreover, the effect of different visible light source of similar irradiance, such as compact fluorescent lamp (CFL) and light emitting diode (LED), is also investigated in this research. The performance of nanophotocatalysts was found to be comparatively higher under ~310 µW cm-2 irradiance with peak emissive wavelengths of 543 nm emitted by CFL. Therefore, a promising visible-light-driven magnetically separable TiO2-based nanophotocatalysts was synthesized for the efficient degradation of ibuprofen.

Keywords: ibuprofen, magnetic N-TiO2, photocatalysis, visible light sources

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Authors: Samar Mousa, Galini Mavromatidou, Rebecca Shirley

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Surgeons carry out numerous operations in the busy burns and plastic surgery department daily. Writing an accurate operation note with all the essential information is crucial for communication not only within the plastics team but also to the multi-disciplinary team looking after the patient, including other specialties, nurses and GPs. The Royal college of surgeons of England, in its guidelines of good surgical practice, mentioned that the surgeon should ensure that there are clear (preferably typed) operative notes for every procedure. The notes should accompany the patient into recovery and to the ward and should give sufficient detail to enable continuity of care by another doctor. The notes should include the Date and time, Elective/emergency procedure, Names of the operating surgeon and assistant, Name of the theatre anesthetist, Operative procedure carried out, Incision, Operative diagnosis, Operative findings, Any problems/complications, Any extra procedure performed and the reason why it was performed, Details of tissue removed, added or altered, Identification of any prosthesis used, including the serial numbers of prostheses and other implanted materials, Details of closure technique, Anticipated blood loss, Antibiotic prophylaxis (where applicable), DVT prophylaxis (where applicable), Detailed postoperative care instructions and Signature. Fourteen random days were chosen in December 2021 to assess the accuracy of operative notes and post-operative care. A total of 163 operative notes were examined. The average completion rates in all domains were 85.4%. An electronic operative note template was designed to cover all domains mentioned in the Royal College of surgeons' good surgical practice. It is kept in the hospital drive for all surgeons to use.

Keywords: operative notes, plastic surgery, documentation, electronic

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Authors: Eric Lai, Sarah Lorger, David Eisinger, Richard Waugh

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Introduction: Percutaneous embolization of varicoceles has shown similar outcomes to surgery. However, there are advantages of radiological intervention as patients are not exposed to general anaesthesia, experience a quicker recovery and face a lower risk of major complications. Radiological interventions are also preferable after a failed surgical approach. We evaluate clinical outcomes of percutaneous embolization at a tertiary hospital in Sydney, Australia. Methods: Retrospective case series without a control group from a single site (Royal Prince Alfred Hospital, Sydney, Australia). A data search was performed on the interventional radiology database with the word “varicocele” between February 2017 and March 2022. 62 patients were identified. Each patient file was reviewed and included in the study if they met the inclusion criteria. Results: A total of 56 patients were included. 6 patients were excluded as they did not receive intervention after the initial diagnostic venography. Technical success was 100%. Complications were seen in 3 patients (5.3%). The complications included post-procedural pain and fever, venous perforation with no clinical adverse outcome, and a mild allergic reaction to contrast. Recurrence occurred in 3 patients (5.6%), all of whom received a successful second procedure. DISCUSSION: This study demonstrates comparable rates of technical success, complication rate and recurrence to other studies in the literature. When compared to surgical outcomes, the results were also similar. The main limitation is multiple patients lack long-term follow-up beyond 1 year, resulting in potential underestimation of the recurrence rate. Conclusion: Percutaneous embolization of varicocele is a safe alternative to surgical intervention.

Keywords: varicocele, interventional radiology, urology, radiology

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Authors: Djamil Guettiche, Ahmed Mekki, Tighilt Fatma-Zohra, Rachid Mahmoud

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The aim of this study was to synthesize and characterize conducting polymer composites of polypyrrole and graphene, including pristine and surface-treated graphene (PPy/GO, PPy/rGO, and PPy/rGO-ArCOOH), for use as sensitive elements in a homemade chemiresistive module for on-line detection of nitrogen oxides vapors. The chemiresistive module was prepared, characterized, and evaluated for performance. Structural and morphological characterizations of the composite were carried out using FTIR, Raman spectroscopy, and XRD analyses. After exposure to NO and NO₂ gases in both static and dynamic modes, the sensitivity, selectivity, limit of detection, and response time of the sensor were determined at ambient temperature. The resulting sensor showed high sensitivity, selectivity, and reversibility, with a low limit of detection of 1 ppm. A composite of polypyrrole and graphene functionalized with aryl 4-carboxy benzene diazonium salt was synthesized and characterized using FTIR, scanning electron microscopy, transmission electron microscopy, UV-visible, and X-ray diffraction. The PPy-rGOArCOOH composite exhibited a good electrical resistance response to NO₂ at room temperature and showed enhanced NO₂-sensing properties compared to PPy-rGO thin films. The selectivity and stability of the NO₂ sensor based on the PPy/rGO-ArCOOH nanocomposite were also investigated.

Keywords: conducting polymers, surface treated graphene, diazonium salt, polypyrrole, Nitrogen oxide sensing

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Authors: Jugoslav Jokovic, Tijana Dimitrijevic, Nebojsa Doncov

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The goal of this paper is to investigate the possibilities and effectiveness of the TLM (Transmission Line Matrix) method for modelling of up-to-date microstrip antennas with circular geometry that have significant application in modern wireless communication systems. The coaxially fed microstrip antenna configurations with circular patch are analyzed by using the in-house 3DTLMcyl_cw solver based on computational electromagnetic TLM method adapted to the cylindrical grid and enhanced with the compact wire model. Opposed to the widely used rectangular TLM mesh, where a staircase approximation has to be used to describe curved boundaries, precise modelling of circular boundaries can be accomplished in the cylindrical grid irrespective of the mesh resolution. Using the compact wire model incorporated in cylindrical mesh, it is possible to model coaxial feed and include the influence of the real excitation in the antenna model. The conventional and inverted configuration of a coaxially fed circular patch antenna are considered, comparing the resonances obtained using TLM cylindrical model with results reached by the corresponding model in a rectangular grid as well as with experimental ones. Bearing in mind that accuracy of simulated results depends on a relevantly created model, besides structure geometry and dimensions, it is important to consider additional modelling issues, regarding appropriate mesh resolution and a relevant extension of a mesh around the considered structure that would provide convergence of the results.

Keywords: computational electromagnetic, coaxial feed, microstrip antenna, TLM modelling

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Authors: P. K. Purohit, Azad A. Mansoori, Parvaiz A. Khan, Purushottam Bhawre, Sharad C. Tripathi, A. M. Aslam, Malik A. Waheed, Shivangi Bhardwaj, A. K. Gwal

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The geomagnetic storm represents the most outstanding example of solar wind-magnetospheric interaction, which causes global disturbances in the geomagnetic field as well as the trigger ionospheric disturbances. We study the behaviour of ionospheric Total Electron Content (TEC) during the geomagnetic storms. For the present investigation we have selected 47 intense geomagnetic storms (Dst ≤ -100nT) that were observed during the solar cycle 23 i.e. during 1998-2006. We then categorized these storms into four categories depending upon their solar sources like Magnetic Cloud (MC), Co-rotating Interaction Region (CIR), SH+ICME and SH+MC. We then studied the behaviour of ionospheric TEC at a mid latitude station Usuda (36.13N, 138.36E), Japan during these storm events produced by four different solar sources. During our study we found that the smooth variations in TEC are replaced by rapid fluctuations and the value of TEC is strongly enhanced during the time of these storms belonging to all the four categories. However, the greatest enhancements in TEC are produced during those geomagnetic storms which are either caused by sheath driven magnetic cloud (SH+MC) or sheath driven ICME (SH+ICME). We also derived the correlation between the TEC enhancements produced during storms of each category with the minimum Dst. We found the strongest correlation exists for the SH+ICME category followed by SH+MC, MC and finally CIR. Since the most intense storms were either caused by SH+ICME or SH+MC while the least intense storms were caused by CIR, consequently the correlation was the strongest with SH+ICME and SH+MC and least with CIR.

Keywords: GPS, TEC, geomagnetic storm, sheath driven magnetic cloud

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Authors: Karnsunaphat Balthip, Bunrome Suwanphahu

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Purpose in life is one attribute of the concept of spirituality which is used in health promotion to promote holistic wellbeing. Purpose is a significant foundation of motivation and achievement that guides adolescents down positive life paths. Adolescents who have life purpose are more likely to achieve greater success and wellbeing in their lives. The current study used qualitative research methodology to describe the experiences that enhanced the purpose in life of 27 Thai adolescents from different backgrounds, living in urban areas in southern Thailand. Data were gathered through in-depth interviews and observation. Thematic analysis methods guided data analysis. The results showed that love and connectedness are important in enhancing purpose in life. They illustrate four attributes of love and connection reflecting the four attributes of gratitude that enhance purpose in life: (1) self-love, or gratitude to oneself, whereby participants endeavor to live life in a positive way by taking care of themselves based on moral and ethical values; (2) connectedness or gratitude to parents or significant others, whereby participants are committed to taking holistic care (physical, psychological, and spiritual) of their significant others; (3) connectedness or gratitude to peers, whereby participants support their peers to help them live their own lives in a positive way; and (4) connectedness or gratitude to the wider world (environment, society, nation and beyond), through a sense of altruism towards others. The findings provide helpful insights for parents, nurses, and other health professionals supporting adolescents to obtain a purpose in life.

Keywords: adolescent, gratitude, purpose in life, spirituality

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Authors: Emad Hafez, Mahmoud Seleiman

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Two field experiments were carried out in order to investigate the effect of chemical inducers [benzothiadiazole 0.9 mM L-1, oxalic acid 1.0 mM L-1, salicylic acid 0.2 mM L-1] on physiological and technological traits as well as on yields and antioxidant enzyme activities of barley grown under abiotic stress (i.e. water surplus and deficit conditions). Results showed that relative water content, leaf area, chlorophyll and yield as well as technological properties of barley were improved with chemical inducers application under water surplus and water-stress conditions. Antioxidant enzymes activity (i.e. catalase and peroxidase) were significantly increased in barley grown under water-stress and treated with chemical inducers. Yield and related parameters of barley presented also significant decrease under water-stress treatment, while chemical inducers application enhanced the yield-related traits. Starch and protein contents were higher in plants treated with salicylic acid than in untreated plants when water-stress was applied. In conclusion, results show that chemical inducers application have a positive interaction and synergetic influence and should be suggested to improve plant growth, yield and technological properties of water stressed barley. Salicylic acid application was better than oxalic acid and benzothiadiazole in terms of plant growth and yield improvement.

Keywords: antioxidant enzymes, drought stress, Hordeum vulgare L., quality, yield

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Authors: S. Abd Rahim, F. A. Rahman, E. M. Nasir, N. A. Ramle

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Co-crystal is believed to improve the solubility and dissolution rates and thus, enhanced the bioavailability of poor water soluble drugs particularly during the oral route of administration. With the existing of poorly soluble drugs in pharmaceutical industry, the screening of co-crystal formation using carbamazepine (CBZ) as a model drug compound with dicarboxylic acids co-crystal formers (CCF) namely fumaric (FA) and succinic (SA) acids in ethanol has been studied. The co-crystal formations were studied by varying the mol ratio values of CCF to CBZ to access the effect of CCF concentration on the formation of the co-crystal. Solvent evaporation, slurry, and cooling crystallisations which representing the solution based method co-crystal screening were used. The product crystal from the screening was characterized using X-ray powder diffraction (XRPD). The XRPD pattern profile analysis has shown that the CBZ co-crystals with FA and SA were successfully formed for all ratios studied. The findings revealed that CBZ-FA co-crystal were formed in two different polymorphs. It was found that CBZ-FA form A and form B were formed from evaporation and slurry crystallisation methods respectively. On the other hand, in cooling crystallisation method, CBZ-FA form A was formed at lower mol ratio of CCF to CBZ and vice versa. This study disclosed that different methods and mol ratios during the co-crystal screening can affect the outcome of co-crystal produced such as polymorphic forms of co-crystal and thereof. Thus, it was suggested that careful attentions is needed during the screening since the co-crystal formation is currently one of the promising approach to be considered in research and development for pharmaceutical industry to improve the poorly soluble drugs.

Keywords: co-crystal, dicarboxylic acid, carbamazepine, industry

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Authors: Zainab M. Almutairi, Amjad Alharbi

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The use of engineered nanomaterials has increased as a result of their positive impact on many sectors of the economy, including agriculture. Silver nanoparticles (AgNPs) are now used to enhance seed germination, plant growth, and photosynthetic quantum efficiency and as antimicrobial agents to control plant diseases. In this study, we examined the effect of AgNP dosage on the seed germination of three plant species: corn (Zea mays L.), watermelon (Citrullus lanatus [Thunb.] Matsum. & Nakai) and zucchini (Cucurbita pepo L.). This experiment was designed to study the effect of AgNPs on germination percentage, germination rate, mean germination time, root length and fresh and dry weight of seedlings for the three species. Seven concentrations (0.05, 0.1, 0.5, 1, 1.5, 2, and 2.5 mg/ml) of AgNPs were examined at the seed germination stage. The three species had different dose responses to AgNPs in terms of germination parameters and the measured growth characteristics. The germination rates of the three plants were enhanced in response to AgNPs. Significant enhancement of the germination percentage values was observed after treatment of the watermelon and zucchini plants with AgNPs in comparison with untreated seeds. AgNPs showed a toxic effect on corn root elongation, whereas watermelon and zucchini seedling growth were positively affected by certain concentrations of AgNPs. This study showed that exposure to AgNPs caused both positive and negative effects on plant growth and germination.

Keywords: citrullus lanatus, cucurbita pepo, seed germination, seedling growth, silver nanoparticles, zea mays

Procedia PDF Downloads 302