Search results for: oxygen ionic conductors

Authors: Shef Amir Arasy

Abstract:

In 2023, the world's population will be 7.8 billion, which has increased significantly in the last 20 years. Every country in the world is experiencing the impacts of climate change directly and indirectly. However, the community still needs to build massive infrastructure and buildings. The massive CO2 emissions which lead to climate change come from cement usage in construction activity. Bamboo is one of the most sustainable materials for reducing carbon emissions and releasing more than 30% oxygen compared to the mass of trees. Besides, bamboo harvest time is faster than other sustainable materials, around 3-4 years. Furthermore, Bamboo has a high tensile strength, which can provide ductility effectively to prevent damage to buildings during an earthquake. By the finite element method, this research analyzes bamboo configuration and connection for tall building structures under different earthquake frequencies and fire. The aim of this research is to provide proper design and connection of bamboo buildings that can be more reliable than concrete structures.

Keywords: bamboo, concrete, ductility, earthquake.

Procedia PDF Downloads 72

Authors: Carolina Guatemala, Josefina Barrera

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A large number of soils highly polluted with recalcitrant hydrocarbons and the limitation of the current bioremediation methods continue being the drawback for an efficient recuperation of these under safe conditions. In this regard, soil washing by degradable surfactants is an alternative option knowing the capacity of surfactants to desorb oily organic compounds. The aim of this study was the establishment of the washing conditions of a soil polluted with diesel, using a nonionic surfactant. A soil polluted with diesel was used. This was collected near to a polluted railway station zone. The soil was dried at room temperature and sieved to a mesh size 10 for its physicochemical and biological characterization. Washing of the polluted soil was performed with surfactant solutions in a 1:5 ratio (5g of soil per 25 mL of the surfactant solution). This was carried out at 28±1 °C and 150 rpm for 72 hours. The factors tested were the Tween 80 surfactant concentration (1, 2, 5 and 10%) and the treatment time. Residual diesel concentration was determined every 24 h. The soil was of a sandy loam texture with a low concentration of organic matter (3.68%) and conductivity (0.016 dS.m- 1). The soil had a pH of 7.63 which was slightly alkaline and a Total Petroleum Hydrocarbon content (TPH) of 11,600 ± 1058.38 mg/kg. The high TPH content could explain the low microbial count of 1.1105 determined as UFC per gram of dried soil. Within the range of the surfactant concentration tested for washing the polluted soil under study, TPH removal increased proportionally with the surfactant concentration. 5080.8 ± 422.2 ppm (43.8 ± 3.64 %) was the maximal concentration of TPH removed after 72 h of contact with surfactant pollution at 10%. Despite the high percentage of hydrocarbons removed, it is assumed that a higher concentration of these could be removed if the washing process is extended or is carried out by stages. Soil washing through the use of surfactants as a desorbing agent was found to be a viable and effective technology for the rapid recovery of soils highly polluted with recalcitrant hydrocarbons.

Keywords: diesel, hydrocarbons, soil washing, tween 80

Procedia PDF Downloads 142

Authors: Nadia Hammouda, Kamel Belmokre

Abstract:

Organic coatings are widely employed in the corrosion protection of most metal surfaces, particularly steel. They provide a barrier against corrosive species present in the environment, due to their high resistance to oxygen, water and ions transport. This study focuses on the evaluation of corrosion protection performance of epoxy paint on the carbon steel surface in sea water by Electrochemical Impedance Spectroscopy (EIS). The electrochemical behavior of painted surface was estimated by EIS parameters that contained paint film resistance, paint film capacitance and double layer capacitance. On the basis of calculation using EIS spectrums it was observed that pore resistance (Rpore) decreased with the appearance of doubled layer capacitance (Cdl) due to the electrolyte penetration through the film. This was further confirmed by the decrease of diffusion resistance (Rd) which was also the indicator of the deterioration of paint film protectiveness.

Keywords: epoxy paints, carbon steel, electrochemical impedance spectroscopy, corrosion mechanisms, seawater

Procedia PDF Downloads 417

Authors: M. Rajasekar, K. Suresh

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Diosmin is a flavonoid, most abundantly found in many citrus fruits. As a flavonoid, it possesses a multitude of biological activities including anti-hyperglycemic, anti-lipid peroxidative, anti-inflammatory, antioxidant, and anti-mutagenic properties. At this point, we established the anti-proliferative and apoptosis-inducing activities of diosmin in Hep-2 and KB cells. Diosmin has cytotoxic effects through inhibiting cellular proliferation of Hep-2 and KB cells, which leads to the induction of apoptosis, as apparent by an increase in the fraction of cells in the sub-G1phase of the cell cycle. Results exposed that inhibition of cell proliferation is associated with regulation of the Interleukins/STAT pathway. In addition, Diosmin treatment with Hep-2 and KB cells actively stimulated reactive oxygen species (ROS) and mitochondrial membrane depolarization. And also an imbalance in the Bax/Bcl-2 ratio triggered the caspase cascade and shifting the balance in favor of apoptosis. These observations conclude that Diosmin induce apoptosis via Interleukins /STAT-mediated pathway.

Keywords: diosmin, apoptosis, antioxidant, STAT pathway

Procedia PDF Downloads 328

Authors: Gheorghe Braniste

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The management of the training process in sports is closely related to the awareness of the close connection between performance and the morphological, functional and psychological characteristics of the athlete's body. Achieving high results in Olympic sports is influenced, on the one hand, by the genetically determined characteristics of the body and, on the other hand, by the morphological, functional and motor abilities of the athlete. Taking into account the importance of properly understanding the evolutionary specificity of athletes to assess their competitive potential, this study provides a comparative analysis of the parameters that characterize the growth and development of the level of adaptation of sweeping rowers, considering the growth interval between 12 and 20 years. The study established that, in the multi-annual training process, the bodies of the targeted athletes register significant adaptive changes while analyzing parameters of the morphological, functional, psychomotor and sports-technical spheres. As a result of the influence of physical efforts, both specific and non-specific, there is an increase in the adaptability of the body, its transfer to a much higher level of functionality within the parameters, useful and economical adaptive reactions influenced by environmental factors, be they internal or external. The research was carried out for 7 years, on a group of 28 athletes, following their evolution and recording the specific parameters of each age stage. In order to determine the level of physical, morpho-functional, psychomotor development and technical training of rowers, the screening data were applied at the State University of Physical Education and Sports in the Republic of Moldova. During the research, measurements were made on the waist, in the standing and sitting position, arm span, weight, circumference and chest perimeter, vital capacity of the lungs, with the subsequent determination of the vital index (tolerance level to oxygen deficiency in venous blood in Stange and Genchi breath-taking tests that characterize the level of oxygen saturation, absolute and relative strength of the hand and back, calculation of body mass and morphological maturity indices (Kettle index), body surface area (body gait), psychomotor tests (Romberg test), test-tepping 10 s., reaction to a moving object, visual and auditory-motor reaction, recording of technical parameters of rowing on a competitive distance of 200 m. At the end of the study it was found that highly performance is sports is to be associated on the one hand with the genetically determined characteristics of the body and, on the other hand, with favorable adaptive reactions and energy saving, as well as morphofunctional changes influenced by internal and external environmental factors. The importance of the results obtained at the end of the study was positively reflected in obtaining the maximum level of training of athletes in order to demonstrate performance in large-scale competitions and mostly in the Olympic Games.

Keywords: olympics, parameters, performance, peak

Procedia PDF Downloads 123

Authors: Mamdouh Y. Saleh, Gaber El Enany, Medhat H. Elzahar, Moustafa H. Omran

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The discharge limits of industrial waste water effluents are subjected to regulations which are getting more restricted with time. A former research occurred in Port Said city studied the efficiency of treating industrial wastewater using the first stage (A-stage) of the multiple-stage plant (AB-system).From the results of this former research, the effluent treated wastewater has high rates of total dissolved solids (TDS) and chemical oxygen demand (COD). The purpose of this paper is to improve the treatment process in removing TDS and COD. Thus, a pilot plant was constructed at wastewater pump station in the industrial area in the south of Port Said. Experimental work was divided into several groups adding activated carbon with different dosages to waste water, and for each group waste water was filtered after being mixed with activated carbon. pH and TSS as variables were also studied. At the end of this paper, a comparison was made between the efficiency of using activated carbon and the efficiency of using limestone in the same circumstances.

Keywords: adsorption, COD removal, filtration, TDS removal

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Authors: Jana Rejková, Marie Kudrnová

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This paper deals with the research of materials for one of the types of reactors IV. generation - reactor with molten salts. One of the advantages of molten salts applied as a coolant in reactors is the ability to operate at relatively low pressures, as opposed to cooling with water or gases. Compared to liquid metal cooling, which also allows lower operating pressures, salt melts are less prone to chemical reactions. The service life of the construction materials used is limited by the operating temperatures of the reactor and the content of impurities in the salts. For the research of corrosion resistance, an experimental device was designed and assembled, enabling exposure at high temperatures without access to oxygen in a flowing atmosphere of inert gas. Nickel alloys Inconel 601, 617, and 625 were tested in a mixture of chloride salts LiCl – KCl (58,2 - 41,8 wt. %). The experiment showed high resistance of the materials used and based on the results and XPS analysis, other construction materials were proposed for the experiments.

Keywords: molten salt, corrosion, nuclear reactor, nickel alloy

Procedia PDF Downloads 165

Authors: M. Pourshirazi, M. Esmaelifar, A. Aliahmadi, F. Yazdian, A. S. Hatamian Zarami, S. J. Ashrafi

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Monascus purpureus is an antioxidant-producing fungus whose secondary metabolites can be used in drug industries. The growth yield and antioxidant activity of extract were investigated in 3-L liquid fermentation media in a 5-L stirred tank bioreactor (STD) at 30°C, pH 5.93 and darkness for 4 days with 150 rpm agitation and 40% dissolved oxygen. Results were compared to extract isolated from Erlenmeyer flask with the same condition. The growth yield was 0.21 and 0.17 in STD condition and Erlenmeyer flask, respectively. Furthermore, the IC50 of DPPH scavenging activity was 256.32 µg/ml and 150.43 µg/ml for STD extract and flask extract, respectively. Our data demonstrated that transferring the growth condition into the STD caused an increase in growth yield but not in antioxidant activity. Accordingly, there is no relationship between growth rate and secondary metabolites formation. More studies are needed to determine the mass transfer coefficient and also evaluating the hydrodynamic condition have to be done in the future studies.

Keywords: Monascus purpureus, bioreactor, antioxidant, growth yield

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

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

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

Procedia PDF Downloads 218

Authors: Hady Hamidyan

Abstract:

As the global population continues to grow, the demand for clean water and effective wastewater treatment becomes increasingly critical. By 2030, global water demand is projected to exceed supply by 40%, driven by population growth, increased water usage, and climate change. Currently, about 4.2 billion people lack access to safely managed sanitation services. The wastewater treatment sector faces numerous challenges, including the need for energy-efficient solutions, cost-effectiveness, ease of use, and low maintenance requirements. This abstract presents a groundbreaking wastewater treatment technology that addresses these challenges by offering an energy-saving approach, wastewater recovery capabilities, and a ready-made, affordable, and user-friendly package with minimal maintenance costs. The unique design of this ready-made package made it possible to eliminate the need for pumps, filters, airlift, and other common equipment. Consequently, it enables sustainable wastewater treatment management with exceptionally low energy and cost requirements, minimizing investment and maintenance expenses. The operation of these packages is based on continuous aeration, which involves injecting oxygen gas or air into the aeration chamber through a tubular diffuser with very small openings. This process supplies the necessary oxygen for aerobic bacteria. The recovered water, which amounts to almost 95% of the input, can be treated to meet specific quality standards, allowing safe reuse for irrigation, industrial processes, or even potable purposes. This not only reduces the strain on freshwater resources but also provides economic benefits by offsetting the costs associated with freshwater acquisition and wastewater discharge. The ready-made, affordable, and user-friendly nature of this technology makes it accessible to a wide range of users, including small communities, industries, and decentralized wastewater treatment systems. The system incorporates user-friendly interfaces, simplified operational procedures, and integrated automation, facilitating easy implementation and operation. Additionally, the use of durable materials, efficient equipment, and advanced monitoring systems significantly reduces maintenance requirements, resulting in low overall life-cycle costs and alleviating the burden on operators and maintenance personnel. In conclusion, the presented wastewater treatment technology offers a comprehensive solution to the challenges faced by the industry. Its energy-saving approach, combined with wastewater recovery capabilities, ensures sustainable resource management and enhances environmental stewardship. This affordable, ready-made, and low-maintenance package promotes broad adoption across various sectors and communities, contributing to a more sustainable future for water and wastewater management.

Keywords: wastewater treatment, energy saving, wastewater recovery, affordable package, low maintenance costs, sustainable resource management, environmental stewardship

Procedia PDF Downloads 92

Authors: Po-Ting Chen, Santhanamoorthi Nachimuthu, Jyh-Chiang Jiang

Abstract:

Classical molecular dynamics (CMD) simulations are highly efficient for material simulations but have limited accuracy. In contrast, ab initio molecular dynamics (AIMD) provides high precision by solving the Kohn–Sham equations yet requires significant computational resources, restricting the size of systems and time scales that can be simulated. To address these challenges, we employed NequIP, a machine learning model based on an E(3)-equivariant graph neural network, to accelerate molecular dynamics simulations of a 1M LiPF6 in EC/EMC (v/v 3:7) for Li battery applications. AIMD calculations were initially conducted using the Vienna Ab initio Simulation Package (VASP) to generate highly accurate atomic positions, forces, and energies. This data was then used to train the NequIP model, which efficiently learns from the provided data. NequIP achieved AIMD-level accuracy with significantly less training data. After training, NequIP was integrated into the LAMMPS software to enable molecular dynamics simulations of larger systems over longer time scales. This method overcomes the computational limitations of AIMD while improving the accuracy limitations of CMD, providing an efficient and precise computational framework. This study showcases NequIP’s applicability to electrolyte systems, particularly for simulating the dynamics of LiPF6 ionic mixtures. The results demonstrate substantial improvements in both computational efficiency and simulation accuracy, highlighting the potential of machine learning models to enhance molecular dynamics simulations.

Keywords: lithium-ion batteries, electrolyte simulation, molecular dynamics, neural network

Procedia PDF Downloads 19

Authors: S. J. Kim, Y. J. Yoo

Abstract:

Slack-tide sampling was carried out at seven stations at high and low tides for a tidal cycle, in summer (7, 8, 9) and fall (10), 2016 to determine the differences of water quality according to tides in Masan Bay. The data were analyzed by Pearson correlation and factor analysis. The mixing state of all the water quality components investigated is well explained by the correlation with salinity (SAL). Turbidity (TURB), dissolved silica (DSi), nitrite and nitrate nitrogen (NNN) and total nitrogen (TN), which find their way into the bay from the streams and have no internal source and sink reaction, showed a strong negative correlation with SAL at low tide, indicating the property of conservative mixing. On the contrary, in summer and fall, dissolved oxygen (DO), hydrogen sulfide (H2S) and chemical oxygen demand with KMnO4 (CODMn) of the surface and bottom water, which were sensitive to an internal source and sink reaction, showed no significant correlation with SAL at high and low tides. The remaining water quality parameters showed a conservative or a non-conservative mixing pattern depending on the mixing characteristics at high and low tides, determined by the functional relationship between the changes of the flushing time and the changes of the characteristics of water quality components of the end-members in the bay. Factor analysis performed on the concentration difference data sets between high and low tides helped in identifying the principal latent variables for them. The concentration differences varied spatially and temporally. Principal factors (PFs) scores plots for each monitoring situation showed high associations of the variations to the monitoring sites. At sampling station 1 (ST1), temperature (TEMP), SAL, DSi, TURB, NNN and TN of the surface water in summer, TEMP, SAL, DSi, DO, TURB, NNN, TN, reactive soluble phosphorus (RSP) and total phosphorus (TP) of the bottom water in summer, TEMP, pH, SAL, DSi, DO, TURB, CODMn, particulate organic carbon (POC), ammonia nitrogen (AMN), NNN, TN and fecal coliform (FC) of the surface water in fall, TEMP, pH, SAL, DSi, H2S, TURB, CODMn, AMN, NNN and TN of the bottom water in fall commonly showed up as the most significant parameters and the large concentration differences between high and low tides. At other stations, the significant parameters showed differently according to the spatial and temporal variations of mixing pattern in the bay. In fact, there is no estuary that always maintains steady-state flow conditions. The mixing regime of an estuary might be changed at any time from linear to non-linear, due to the change of flushing time according to the combination of hydrogeometric properties, inflow of freshwater and tidal action, And furthermore the change of end-member conditions due to the internal sinks and sources makes the occurrence of concentration difference inevitable. Therefore, when investigating the water quality of the estuary, it is necessary to take a sampling method considering the tide to obtain average water quality data.

Keywords: conservative mixing, end-member, factor analysis, flushing time, high and low tide, latent variables, non-conservative mixing, slack-tide sampling, spatial and temporal variations, surface and bottom water

Procedia PDF Downloads 130

Authors: Nadia Hammouda, K. Belmokre

Abstract:

Organic coatings are widely employed in the corrosion protection of most metal surfaces, particularly steel. They provide a barrier against corrosive species present in the environment, due to their high resistance to oxygen, water and ions transport. This study focuses on the evaluation of corrosion protection performance of epoxy paint on the carbon steel surface in sea water by Electrochemical Impedance Spectroscopy (EIS). The electrochemical behavior of painted surface was estimated by EIS parameters that contained paint film resistance, paint film capacitance and double layer capacitance. On the basis of calculation using EIS spectrums it was observed that pore resistance (Rpore) decreased with the appearance of doubled layer capacitance (Cdl) due to the electrolyte penetration through the film. This was further confirmed by the decrease of diffusion resistance (Rd) which was also the indicator of the deterioration of paint film protectiveness.

Keywords: epoxy paints, carbon steel, electrochemical impedance spectroscopy, corrosion mechanisms, sea water

Procedia PDF Downloads 481

Authors: Kumlachew Zelalem Walle, Chun-Chen Yang

Abstract:

Solid-state Lithium metal batteries (SSLMBs) that contain polymer and ceramic solid electrolytes have received considerable attention as an alternative to substitute liquid electrolytes in lithium metal batteries (LMBs) for highly safe, excellent energy storage performance and stability under elevated temperature situations. Here, a novel fast Li-ion conducting material, LiTa₂PO₈ (LTPO), was synthesized and electrochemical performance of as-prepared powder and LTPO-incorporated composite solid polymer electrolyte (LTPO-CPE) membrane were investigated. The as-prepared LTPO powder was homogeneously dispersed in polymer matrices, and a hybrid solid electrolyte membrane was synthesized via a simple solution-casting method. The room temperature total ionic conductivity (σt) of the LTPO pellet and LTPO-CPE membrane were 0.14 and 0.57 mS cm-1, respectively. A coin battery with NCM811 cathode is cycled under 1C between 2.8 to 4.5 V at room temperature, achieving a Coulombic efficiency of 99.3% with capacity retention of 74.1% after 300 cycles. Similarly, the LFP cathode also delivered an excellent performance at 0.5C with an average Coulombic efficiency of 100% without virtually capacity loss (the maximum specific capacity is at 27th: 138 mAh g−1 and 500th: 131.3 mAh g−1). These results demonstrates the feasibility of a high Li-ion conductor LTPO as a filler, and the developed polymer/ceramic hybrid electrolyte has potential to be a high-performance electrolyte for high-voltage cathodes, which may provide a fresh platform for developing more advanced solid-state electrolytes.

Keywords: li-ion conductor, lithium-metal batteries, composite solid electrolytes, liTa2PO8, high-voltage cathode

Procedia PDF Downloads 66

Authors: Weixiang Liu, Yukun Qin, Song Liu, Pengcheng Li

Abstract:

Plant diseases can cause the death of crops with great economic losses. Particularly, those diseases are usually caused by pathogenic fungi. Metal fungicides are a type of pesticide that has advantages of a low-cost, broad antimicrobial spectrum and strong sterilization effect. However, the frequent and wide application of traditional metal fungicides has caused serious problems such as environmental pollution, the outbreak of mites and phytotoxicity. Therefore, it is critically necessary to discover new organic metal fungicides alternatives that have a low metal content, low toxicity, and little influence on mites. Chitosan, the second most abundant natural polysaccharide next to cellulose, was proved to have broad-spectrum antifungal activity against a variety of fungi. However, the use of chitosan was limited due to its poor solubility and weaker antifungal activity compared with commercial fungicide. Therefore, in order to improve the water solubility and antifungal activity, many researchers grafted the active groups onto chitosan. The present work was to combine free metal ions with chitosan, to prepare more potent antifungal chitosan derivatives, thus, based on condensation reaction, chitosan derivative bearing amino pyridine group was prepared and subsequently followed by coordination with cupric ions, zinc ions and nickel ions to synthesize chitosan metal complexes. The calculations by density functional theory (DFT) show that the copper ions and nickel ions underwent dsp2 hybridization, the zinc ions underwent sp3 hybridization, and all of them are coordinated by the carbon atom in the p-π conjugate group and the oxygen atoms in the acetate ion. The antifungal properties of chitosan metal complexes against Phytophthora capsici (P. capsici), Gibberella zeae (G. zeae), Fusarium oxysporum (F. oxysporum) and Botrytis cinerea (B. cinerea) were also assayed. In addition, a plant toxicity experiment was carried out. The experiments indicated that the derivatives have significantly enhanced antifungal activity after metal ions complexation compared with the original chitosan. It was shown that 0.20 mg/mL of O-CSPX-Cu can 100% inhibit the growth of P. capsici and 0.20 mg/mL of O-CSPX-Ni can 87.5% inhibit the growth of B. cinerea. In general, their activities are better than the positive control oligosaccharides. The combination of the pyridine formyl groups seems to favor biological activity. Additionally, the ligand fashion was precisely analyzed, and the results revealed that the copper ions and nickel ions underwent dsp2 hybridization, the zinc ions underwent sp3 hybridization, and the carbon atoms of the p-π conjugate group and the oxygen atoms of acetate ion are involved in the coordination of metal ions. The phytotoxicity assay of O-CSPX-M was also conducted, unlike the traditional metal fungicides, the metal complexes were not significantly toxic to the leaves of wheat. O-CSPX-Zn can even increase chlorophyll content in wheat leaves at 0.40 mg/mL. This is mainly because chitosan itself promotes plant growth and counteracts the phytotoxicity of metal ions. The chitosan derivative described here may lend themselves to future applicative studies in crop protection.

Keywords: coordination, chitosan, metal complex, antifungal properties

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Authors: M. R. S. Nasuha, K. Azman, H. Azhan, S. A. Senawi, A. Mardhiah

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Studies on Samarium doped glasses possess lot of interest due to their potential applications for high-density optical memory, optical communication device, the design of laser and color display etc. Sm3+ doped borotellurite glasses of the system (70-x) TeO2-20B2O3-10ZnO-xSm2O3 (where x = 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol%) have been prepared using melt-quenching method. Their physical properties such as density, molar volume and oxygen packing density as well as the optical measurements by mean of their absorption and emission characteristic have been carried out at room temperature using UV/VIS and photoluminescence spectrophotometer. The results of physical properties are found to vary with respect to Sm3+ ions content. Meanwhile, three strong absorption peaks are observed and are well resolved in the ultra violet and visible regions due to transitions between the ground state and various excited state of Sm3+ ions. Thus, the photoluminescence spectra exhibit four emission bands from the initial state, which correspond to the 4G5/2 → 6H5/2, 4G5/2 → 6H7/2, 4G5/2 → 6H9/2 and 4G5/2 → 6H11/2 fluorescence transitions at 562 nm, 599 nm, 645 nm and 706 nm respectively.

Keywords: absorption, borotellurite, down-conversion, emission

Procedia PDF Downloads 684

Authors: Arindam Pramanik, Parimal Karmakar

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We have explored the synergistic anti-cancer activity of copper ion and acetylacetone complex containing 1,3 diketone group (like curcumin) in metallorganic compound “Copper acetylacetonate” (CuAA). The cytotoxicity mechanism of CuAA complex was evaluated on various cancer cell lines in vitro. Among these, reactive oxygen species (ROS), glutathione level (GSH) in the cell was found to increase. Further mitochondrial membrane damage was observed. The fate of cell death was found to be induced by apoptosis. For application purpose, we have developed a novel biodegradable, non-toxic polymer-based nanoparticle which has hydrophobically modified core for loading of the CuAA. Folic acid is conjugated on the surface of the polymer (chitosan) nanoparticle for targeting to cancer cells for minimizing toxicity to normal cells in-vivo. Thus, this novel drug CuAA has an efficient anticancer activity which has been targeted specifically to cancer cells through polymer nanoparticle.

Keywords: anticancer, apoptosis, copper nanoparticle, targeted drug delivery

Procedia PDF Downloads 484

Authors: Changshan Zhang, Zhijin Yu, Shixing Fan

Abstract:

A comprehensive hazard evaluation for coal self-heating in composite long-wall gobs is heavily dependent on computational simulation. In this study, the spatial distributions of cracks which caused significant air leakage were simulated by universal distinct element code (UDEC) simulation. Based on the main routes of air leakage and characteristics of coal self-heating, a computational fluid dynamics (CFD) modeling was conducted to model the coal spontaneous combustion dangerous area in composite long-wall gobs. The results included the oxygen concentration distributions and temperature profiles showed that the numerical approach is validated by comparison with the test data. Furthermore, under the conditions of specific engineering, the major locations where some techniques for extinguishing and preventing long-wall gob fires need to be put into practice were also examined.

Keywords: computational simulation, UDEC simulation, coal self-heating, CFD modeling, long-wall gobs

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Authors: M. A. Mamun, M. I. Khan, M. H. Sarker, K. A. Khan, M. Shajahan

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The study was carried out to investigate on an innovative invention, Pathor Kuchi Leaf (PKL) cell, which is fueled with PKL sap of widely available plant called Bryophyllum pinnatum as an energy source for use in PKL battery to generate electricity. This battery, a primary source of electricity, has several order of magnitude longer shelf-lives than the traditional Galvanic cell battery, is still under investigation. In this regard, we have conducted some experiments using various instruments including Atomic Absorption Spectrophotometer (AAS), Ultra-Violet Visible spectrophotometer (UV-Vis), pH meter, Ampere-Volt-Ohm Meter (AVO Meter), etc. The AAS, UV-Vis, and pH-metric analysis data provided that the potential and current were produced as the Zn electrode itself acts as reductant while Cu2+ and H+ ions are behaving as the oxidant. The significant influence of secondary salt on current and potential leads to the dissociation of weak organic acids in PKL juice, and subsequent enrichment to the reactant ions by the secondary salt effects. However, the liquid junction potential was not as great as minimized with the opposite transference of organic acid anions and H+ ions as their dissimilar ionic mobilities. Moreover, the large value of the equilibrium constant (K) implies the big change in Gibbs free energy (∆G), the more electromotive force works in electron transfer during the forward electrochemical reaction which coincides with the fast reduction of the weight of zinc plate, revealed the additional electrical work in the presence of PKL sap. This easily fabricated high-performance PKL battery can show an excellent promise during the off-peak across the countryside.

Keywords: Atomic Absorption Spectrophotometer (AAS), Bryophylum Pinnatum Leaf (BPL), electricity, electrochemistry, organic acids

Procedia PDF Downloads 325

Authors: Shailendra Kumar, Lokesh Kashyap, Puneet Khanna, Nishant Patel, Rakesh Kumar, Arshad Ayub, Kelika Prakash, Yudhyavir Singh, Krithikabrindha V.

Abstract:

Introduction: Spinal anesthesia is considered a standard anesthesia technique for caesarean delivery. The incidence of spinal hypotension during caesarean delivery is 70 -80%. Spinal hypotension may cause cerebral hypoperfusion in the mother, but physiologically cerebral autoregulatory mechanisms accordingly prevent cerebral hypoxia. Cerebral blood flow remains constant in the 50-150 mmHg of Cerebral Perfusion Pressure (CPP) range. Near-infrared spectroscopy (NIRS) is a non-invasive technology that is used to detect Cerebral Desaturation Events (CDEs) immediately compared to other conventional intraoperative monitoring techniques. Objective: The primary aim of the study is to correlate the change in cerebral oxygen saturation using NIRS with respect to a fall in mean blood pressure after spinal anaesthesia and to find out the effects of spinal hypotension on neonatal APGAR score, neonatal acid-base variations, and presence of Postoperative Delirium (POD). Methodology: NIRS sensors were attached to the forehead of all the patients, and their baseline readings of cerebral oxygenation on the right and left frontal regions and mean blood pressure were noted. Subarachnoid block was given with hyperbaric 0.5% bupivacaine plus fentanyl, the dose being determined by the individual anaesthesiologist. Co-loading of IV crystalloid solutions was given to the patient. Blood pressure reading and cerebral saturation were recorded every 1 minute till 30min. Hypotension was a fall in MAP less than 20% of the baseline values. Patients going for hypotension were treated with an IV Bolus of phenylephrine/ephedrine. Umbilical cord blood samples were taken for blood gas analysis, and neonatal APGAR was noted by a neonatologist. Study design: A prospective observational study conducted in a population of Thirty ASA 2 and 3 parturients scheduled for lower segment caesarean section (LSCS). Results: Mean fall in regional cerebral saturation is 28.48 ± 14.7% with respect to the mean fall in blood pressure 38.92 ± 8.44 mm Hg. The correlation coefficient between fall in saturation and fall in mean blood pressure is 0.057, and p-value {0.7} after subarachnoid block. A fall in regional cerebral saturation occurred 2±1 min before a fall in mean blood pressure. Twenty-nine out of thirty patients required vasopressors during hypotension. The first dose of vasopressor requirement is needed at 6.02±2 min after the block. The mean APGAR score was 7.86 and 9.74 at 1 and 5 min of birth, respectively, and the mean umbilical arterial pH of 7.3±0.1. According to DRS-98 (Delirium Rating Scale), the mean delirium rating score on postoperative day 1 and day 2 were 0.1 and 0.7, respectively. Discussion: There was a fall in regional cerebral oxygen saturation, which started before with respect to a significant fall in mean blood pressure readings but was statistically not significant. Maximal fall in blood pressure requiring vasopressors occurs within 10 min of SAB. Neonatal APGAR scores and acid-base variations were in the normal range with maternal hypotension, and there was no incidence of postoperative delirium in patients with post-spinal hypotension.

Keywords: cerebral oxygenation, LSCS, NIRS, spinal hypotension

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Authors: Eddy K. Mukadi

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The aim of this study was to provide contributing elements to improve the management of the asthma crisis in the intensive care unit of the General Reference Hospital of Kinshasa. This was a descriptive study of all patients in the intensive care unit presenting with the asthma attack during the period from February 5, 2013 to February 5, 2014. The main data were obtained from consultation registry and medical records. A total of 35 patients, 21 of whom were male (majority) compared to 14 female. Average age of patients was 46.48 plus or minus 16.98 with extremes ranging from 21-75 years. The clinic was dominated by dyspnea in 100% of cases, followed by rales with 91.4% of cases. In spite of the control of the crisis obtained after the treatment with B2 mimetic by inhalation was introduced A 91.5%; 88% corticosteroids; 80% oxygen, the therapeutic principle recommended for the management of asthma attacks was not respected in the majority of cases. This is why we suggest that improving the quality of care to be administered to patients will yield more adequate results.

Keywords: asthma crisis, intensive care, general hospital, Kinshasa

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Authors: Pramod Jagtap, Kisan Jadhav, Neha Dand

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Risperidone (RISP) is an antipsychotic agent and has low water solubility and nontargeted delivery results in numerous side effects. Hence, an attempt was made to develop SLNs hydrogel for intranasal delivery of RISP to achieve maximum bioavailability and reduction of side effects. RISP loaded SLNs composed of 1.65% (w/v) lipid mass were produced by high shear homogenization (HSH) coupled ultrasound (US) method using glyceryl monostearate (GMS) or Imwitor 900K (solid lipid). The particles were loaded with 0.2% (w/v) of the RISP & surface-tailored with a 2.02% (w/v) non-ionic surfactant Tween® 80. Optimization was done using 32 factorial design using Design Expert® software. The prepared SLNs dispersion incorporated into Polycarbophil AA1 hydrogel (0.5% w/v). The final gel formulation was evaluated for entrapment efficiency, particle size, rheological properties, X ray diffraction, in vitro diffusion, ex vivo permeation using sheep nasal mucosa and histopathological studies for nasocilliary toxicity. The entrapment efficiency of optimized SLNs was found to be 76 ± 2 %, polydispersity index <0.3., particle size 278 ± 5 nm. This optimized batch was incorporated into hydrogel. The pH was found to be 6.4 ± 0.14. The rheological behaviour of hydrogel formulation revealed no thixotropic behaviour. In histopathology study, there was no nasocilliary toxicity observed in nasal mucosa after ex vivo permeation. X-ray diffraction data shows drug was in amorphous form. Ex vivo permeation study shows controlled release profile of drug.

Keywords: ex vivo, particle size, risperidone, solid lipid nanoparticles

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Authors: Nadia Hammouda, Kamel Belmokre

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Organic coatings are widely employed in the corrosion protection of most metal surfaces, particularly steel. They provide a barrier against corrosive species present in the environment, due to their high resistance to oxygen, water and ions transport. This study focuses on the evaluation of corrosion protection performance of epoxy paint on the carbon steel surface in sea water by Electrochemical Impedance Spectroscopy (EIS). The electrochemical behavior of painted surface was estimated by EIS parameters that contained paint film resistance, paint film capacitance and double layer capacitance. On the basis of calculation using EIS spectrums it was observed that pore resistance (Rpore) decreased with the appearance of doubled layer capacitance (Cdl) due to the electrolyte penetration through the film. This was further confirmed by the decrease of diffusion resistance (Rd) which was also the indicator of the deterioration of paint film protectiveness.

Keywords: epoxy paints, carbon steel, electrochemical impedance spectroscopy, corrosion mechanisms, sea water

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Authors: Dheyaa Wajid Abbood, Hanan Hussien Abood

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Stepped cascade has been utilized as a hydraulic structure for years. It has proven to be the least costly aeration system in replenishing dissolved oxygen. Numerical modeling of stepped cascade with end sill is very complicated and challenging because of the high roughness and velocity re circulation regions. Volume of fluid multiphase flow model (VOF) is used .The realizable k-ξ model is chosen to simulate turbulence. The computational results are compared with lab-scale stepped cascade data. The lab –scale model was constructed in the hydraulic laboratory, Al-Mustansiriya University, Iraq. The stepped cascade was 0.23 m wide and consisted of 3 steps each 0.2m high and 0.6 m long with variable end sill. The discharge was varied from 1 to 4 l/s. ANSYS has been employed to simulate the experimental data and their related results. This study shows that ANSYS is able to predict results almost the same as experimental findings in some regions of the structure.

Keywords: stepped cascade weir, aeration, multiphase flow model, ansys

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Authors: Syazwani Idrus, S. Charles J. Banks, Sonia Heaven

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The study compared the performance of upflow anaerobic sludge blanket (UASB) reactors and anaerobic filters (AF) for the treatment of wheat straw washwater (WSW) which has a high concentration of Potassium ions. The trial was conducted at mesophilic temperatures (37 °C). The digesters were started up over a 48-day period using a synthetic wastewater feed and reached an organic loading rate (OLR) of 6 g COD L^-1 day^-1 with a specific methane production (SMP) of 0.333 L CH4 g^-1 COD. When the feed was switched to WSW it was not possible to maintain the same loading rate as the SMP in all reactors fell sharply to less than 0.1 L CH4 g^-1 COD, with the AF affected more than the UASB. On reducing the OLR to 3 g COD L^-1 day^-1 the reactors recovered to produce 0.21 L CH4 g^-1 CODadded and gave 82% COD removal. A discrepancy between the COD consumed and the methane produced could be accounted for through increased maintenance energy requirement of the microbial community for osmo-regulation as K+ was found to accumulate in the sludge and in the UASB reached a concentration of 4.5 mg K g^-1 wet weight of granules.

Keywords: anaerobic digestion, osmotic stress, chemical oxygen demand, specific methane production

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Authors: Kyoung Lee

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Numerous aerobic bacteria have the ability to form multicellular communities on the surface layer of the air-liquid (A-L) interface as a biofilm called a pellicle. Pellicles occupied at the A-L interface will benefit from the utilization of oxygen from air and nutrient from liquid. Buoyancy of cells can be obtained by high surface tension at the A-L interface. Thus, formation of pellicles is an adaptive advantage in utilization of excess nutrients in the standing culture where oxygen depletion is easily set up due to rapid cell growth. In natural environments, pellicles are commonly observed on the surface of lake or pond contaminated with pollutants. Previously, we have shown that when cultured in standing LB media an alkylphenol-degrading bacteria Pseudomonas alkylphenolia KL28 forms pellicles in a diameter of 0.3-0.5 mm with a thickness of ca 40 µm. The pellicles have unique features for possessing flatness and unusual rigidity. In this study, the biogenesis of the circular pellicles has been investigated by observing the cell organization at early stages of pellicle formation and cell arrangements in pellicle, providing a clue for highly organized cellular arrangement to be adapted to the air-liquid niche. Here, we first monitored developmental patterns of pellicle from monolayer to multicellular organization. Pellicles were shaped by controlled growth of constituent cells which accumulate extracellular polymeric substance. The initial two-dimensional growth was transited to multilayers by a constraint force of accumulated self-produced extracellular polymeric substance. Experiments showed that pellicles are formed by clonal growth and even with knock-out of genes for flagella and pilus formation. In contrast, the mutants in the epm gene cluster for alginate-like polymer biosynthesis were incompetent in cell alignment for initial two-dimensional growth of pellicles. Electron microscopic and confocal laser scanning microscopic studies showed that the fully matured structures are highly packed by matrix-encased cells which have special arrangements. The cells on the surface of the pellicle lie relatively flat and inside longitudinally cross packed. HPLC analysis of the extrapolysaccharide (EPS) hydrolysate from the colonies from LB agar showed a composition with L-fucose, L-rhamnose, D-galactosamine, D-glucosamine, D-galactose, D-glucose, D-mannose. However, that from pellicles showed similar neutral and amino sugar profile but missing galactose. Furthermore, uronic acid analysis of EPS hydrolysates by HPLC showed that mannuronic acid was detected from pellicles not from colonies, indicating the epm-derived polymer is critical for pellicle formation as proved by the epm mutants. This study verified that for the circular pellicle architecture P. alkylphenolica KL28 cells utilized EPS building blocks different from that used for colony construction. These results indicate that P. alkylphenolica KL28 is a clever architect that dictates unique cell arrangements with selected EPS matrix material to construct sophisticated building, circular biofilm pellicles.

Keywords: biofilm, matrix, pellicle, pseudomonas

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Authors: Sreetama Ghosh, Sundara Ramaprabhu

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Carbon dioxide gas has been a major cause for the worldwide increase in green house effect, which leads to climate change and global warming. So CO₂ capture & sequestration has become an effective way to reduce the concentration of CO₂ in the environment. One such way to capture CO₂ in porous materials is by adsorption process. A potential material in this aspect is porous hexagonal boron nitride or 'white graphene' which is a well-known two-dimensional layered material with very high thermal stability. It had been investigated that the sample with hierarchical pore structure and high specific surface area shows excellent performance in capturing carbon dioxide gas and thereby mitigating the problem of environmental pollution to the certain extent. Besides, the presence of sulfur as well as nitrogen in the sample synergistically helps in the increase in adsorption capacity. In this work, a cost effective single step synthesis of highly porous boron nitride nanosheets doped with sulfur had been demonstrated. Besides, the CO₂ adsorption-desorption studies were carried on using a pressure reduction technique. The studies show that the nanosheets exhibit excellent cyclic stability in storage performance. Thermodynamic studies suggest that the adsorption takes place mainly through physisorption. The studies show that the nanosheets exhibit excellent cyclic stability in storage performance. Further, the surface modification of the highly porous nano sheets carried out by incorporating ionic liquids had further enhanced the capturing capability of CO₂ gas in the nanocomposite, revealing that this particular material has the potential to be an excellent adsorbent of carbon dioxide gas.

Keywords: CO₂ capture, hexagonal boron nitride nanosheets, porous network, sulfur doping

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Authors: Nibedita Pani, Vishnu Tejani, T. S. Anantha Singh

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Water pollution resulting from discharge of partial/not treated textile wastewater containing high carbon and nitrogen pollutants pose a huge threat to the environment, ecosystem, and human health. It is essential to remove carbon- and nitrogen-based organic pollutants more effectively from industrial wastewater before discharging. The present study focuses on removal of carbon-based pollutant in particular COD (chemical oxygen demand) and nitrogen-based pollutants, in particular, ammoniacal nitrogen by Fenton oxidation process using Fe²⁺ and H₂O₂ as reagents. The study was carried out with high strength wastewater containing initial COD 5632 mg/L and NH⁴⁺-N 1372 mg/L. The major operating condition like pH was varied between 1.0 to 4.0. The maximum degradation was obtained at pH 3.0 taking the molar ratio of Fe²⁺/H₂O₂ as 1:1. At this pH, the removal efficiencies of COD and ammoniacal nitrogen were found to be 77.27% and 74.9%, respectively. The Fenton process can be the best alternative for the simultaneous removal of COD and NH4+-N from industrial wastewater.

Keywords: ammoniacal nitrogen, COD, Fenton oxidation, industrial wastewater

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Authors: Feroz A. Shah, M. H. Balkhi

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The study was aimed at to record the distribution and prevalence of various metazoan parasites of fish from hill stream/coldwater fishes of various water bodies of northwest Himalayan region of India. Snow trout (Schizoth oracids) from eutrophic lakes and fresh water streams were collected from January to December 2012, to study the impact of environmental factors on the dynamics and distribution of parasitic infection. The prevalence of helminth parasites was correlated with available physico-chemical parameters including water temperature, pH and dissolved oxygen (DO). The most abundant parasitic infection recorded during this study was Adenoscolex sp. (Cestode parasite) which showed positive correlation with pH (significant p≤0.05) negative correlation with temperature. The Bothriocephalus was having positive correlation with water temperature while as negative correlation was observed with pH and DO. The correlation between Diplozoon sp. and Clinostomum sp. with the physiochemical parameters were non-significant.

Keywords: hill stream fishes, parasites, Western Himalayas, prevelance

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Authors: Gyeong-Sung Kim, In-soo Ahn, Yong Cho

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SBR (Sequencing Batch Reactor) process is usually applied to membrane water treatment plants to treat its concentrated wastewater. The role of SBR process is to remove COD (Chemical Oxygen Demand) and NH3 from wastewater before discharging it outside of the water treatment plant using microorganism. Microorganism’s nitrification capability is influenced by water temperature because the nitrification rate of the concentrated wastewater becomes ‘zero’ as water temperature approach 0℃. Heating system is necessary to operate SBR in winter season even though the operating cost increase sharply. The operating cost of SBR at ‘D’ RO water treatment plant in Korea was 51.8 times higher in winter (October to March) compare to summer (April to September) season in 2014. Otherwise the effluent water temperature maintained around 8℃ constantly in winter. This study focuses on application heat pump system to recover the thermal energy from the effluent water of ‘D’ RO plant so that the operating cost will be reduced.

Keywords: water treatment, water thermal energy, energy saving, RO, SBR

Procedia PDF Downloads 516