Search results for: functionalized reduced graphene oxide
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5722

Search results for: functionalized reduced graphene oxide

4522 Production of Pig Iron by Smelting of Blended Pre-Reduced Titaniferous Magnetite Ore and Hematite Ore Using Lean Grade Coal

Authors: Bitan Kumar Sarkar, Akashdeep Agarwal, Rajib Dey, Gopes Chandra Das

Abstract:

The rapid depletion of high-grade iron ore (Fe2O3) has gained attention on the use of other sources of iron ore. Titaniferous magnetite ore (TMO) is a special type of magnetite ore having high titania content (23.23% TiO2 present in this case). Due to high TiO2 content and high density, TMO cannot be treated by the conventional smelting reduction. In this present work, the TMO has been collected from high-grade metamorphic terrain of the Precambrian Chotanagpur gneissic complex situated in the eastern part of India (Shaltora area, Bankura district, West Bengal) and the hematite ore has been collected from Visakhapatnam Steel Plant (VSP), Visakhapatnam. At VSP, iron ore is received from Bailadila mines, Chattisgarh of M/s. National Mineral Development Corporation. The preliminary characterization of TMO and hematite ore (HMO) has been investigated by WDXRF, XRD and FESEM analyses. Similarly, good quality of coal (mainly coking coal) is also getting depleted fast. The basic purpose of this work is to find how lean grade coal can be utilised along with TMO for smelting to produce pig iron. Lean grade coal has been characterised by using TG/DTA, proximate and ultimate analyses. The boiler grade coal has been found to contain 28.08% of fixed carbon and 28.31% of volatile matter. TMO fines (below 75 μm) and HMO fines (below 75 μm) have been separately agglomerated with lean grade coal fines (below 75 μm) in the form of briquettes using binders like bentonite and molasses. These green briquettes are dried first in oven at 423 K for 30 min and then reduced isothermally in tube furnace over the temperature range of 1323 K, 1373 K and 1423 K for 30 min & 60 min. After reduction, the reduced briquettes are characterized by XRD and FESEM analyses. The best reduced TMO and HMO samples are taken and blended in three different weight percentage ratios of 1:4, 1:8 and 1:12 of TMO:HMO. The chemical analysis of three blended samples is carried out and degree of metallisation of iron is found to contain 89.38%, 92.12% and 93.12%, respectively. These three blended samples are briquetted using binder like bentonite and lime. Thereafter these blended briquettes are separately smelted in raising hearth furnace at 1773 K for 30 min. The pig iron formed is characterized using XRD, microscopic analysis. It can be concluded that 90% yield of pig iron can be achieved when the blend ratio of TMO:HMO is 1:4.5. This means for 90% yield, the maximum TMO that could be used in the blend is about 18%.

Keywords: briquetting reduction, lean grade coal, smelting reduction, TMO

Procedia PDF Downloads 319
4521 Reduced Glycaemic Impact by Kiwifruit-Based Carbohydrate Exchanges Depends on Both Available Carbohydrate and Non-Digestible Fruit Residue

Authors: S. Mishra, J. Monro, H. Edwards, J. Podd

Abstract:

When a fruit such as kiwifruit is consumed its tissues are released from the physical /anatomical constraints existing in the fruit. During digestion they may expand several-fold to achieve a hydrated solids volume far greater than the original fruit, and occupy the available space in the gut, where they surround and interact with other food components. Within the cell wall dispersion, in vitro digestion of co-consumed carbohydrate, diffusion of digestion products, and mixing responsible for mass transfer of nutrients to the gut wall for absorption, were all retarded. All of the foregoing processes may be involved in the glycaemic response to carbohydrate foods consumed with kiwifruit, such as breakfast cereal. To examine their combined role in reducing the glycaemic response to wheat cereal consumed with kiwifruit we formulated diets containing equal amounts of breakfast cereal, with the addition of either kiwifruit, or sugars of the same composition and quantity as in kiwifruit. Therefore, the only difference between the diets was the presence of non-digestible fruit residues. The diet containing the entire disperse kiwifruit significantly reduced the glycaemic response amplitude and the area under the 0-120 min incremental blood glucose response curve (IAUC), compared with the equicarbohydrate diet containing the added kiwifruit sugars. It also slightly but significantly increased the 120-180 min IAUC by preventing a postprandial overcompensation, indicating improved homeostatic blood glucose control. In a subsequent study in which we used kiwifruit in a carbohydrate exchange format, in which the kiwifruit carbohydrate partially replaced breakfast cereal in equal carbohydrate meals, the blood glucose was further reduced without a loss of satiety, and with a reduction in insulin demand. The results show that kiwifruit may be a valuable component in low glycaemic impact diets.

Keywords: carbohydrate, digestion, glycaemic response, kiwifruit

Procedia PDF Downloads 492
4520 Influence of Gestational Diabetes Mellitus on the Activity of Steroid C17-Hydroxylase-C17,20-Lyase in Patients with Intrahepatic Cholestasis of Pregnancy

Authors: Leona Ondrejikova, Martin Hill, Antonin Parizek

Abstract:

The incidence of gestational diabetes mellitus (GDM) is higher in women predisposed to developing intrahepatic cholestasis of pregnancy (ICP). Both diseases are associated with altered steroidogenesis when compared with none-ICP controls. However, the effect of GDM on circulating steroids in ICP patients remains unclear. The question remains, whether the levels of circulating steroids differ between ICP patients with and without GDM. In total 10 ICP patients without GDM (ICP+GDM-), 7 ICP patients with GDM (ICP+GDM+), and 15 controls (ICP-GDM-) were monitored during late gestation, at labor, and during three periods postpartum (day 5, week 3, and week 6 postpartum) (Šimják et al., 2018). The relationships between steroid profiles and patients’ status were evaluated using the ANOVA model consisting of subject factor, between-subject factors Group (ICP+GDM+, ICP+GDM-, ICP-GDM-), gestational age at the diagnosis of ICP and gestational age at labor, and within-subject factor Stage and ICP × Stage interaction. The levels of the C21 and C19 Δ5 steroids and 5α/β-reduced C19 steroids were highest in ICP+GDM+, while those for the ICP-GDM-, and ICP+GDM- groups were lower. In the C21 Δ4 steroids and their 5α/β-reduced metabolites, the steroid levels were highest in the ICP+GDM-, intermediate in the ICP-GDM- and lowest in the ICP+GDM+ group. This higher concentration in ICP+GDM- group may be of importance as the 5α-pregnane-3α,20α-diol disulfate, is considered as the substance inducing ICP. In general, these data show that the comorbidity with GDM substantially changes the steroidome in ICP patients towards the higher activity of steroid CYP17A1 lyase step in adrenal zona reticularis reduced CYP17A1 hydroxylase step in zona fasciculata. This is consistent with our previously published hypothesis about the critical role of maternal zona reticularis in the pathophysiology of ICP. Our present data also indicate that the comorbidity with GDM might moderate the gravity of the ICP in this way.

Keywords: CYP17A1, GC-MS, gestational diabetes mellitus, intrahepatic cholestasis of pregnancy

Procedia PDF Downloads 136
4519 Biodegradable Cellulose-Based Materials for the Use in Food Packaging

Authors: Azza A. Al-Ghamdi, Abir S. Abdel-Naby

Abstract:

Cellulose acetate (CA) is a natural biodegradable polymer. It forms transparent films by the casting technique. CA suffers from high degree of water permeability as well as the low thermal stability at high temperatures. To adjust the CA polymeric films to the manufacture of food packaging, its thermal and mechanical properties should be improved. The modification of CA by grafting it with N-Amino phenyl maleimide (N-APhM) led to the construction of hydrophobic branches throughout the polymeric matrix which reduced its wettability as compared to the parent CA. The branches built onto the polymeric chains had been characterized by UV/Vis, 13C-NMR and ESEM. The improvement of the thermal properties was investigated and compared to the parent CA using thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), differential thermal analysis (DTA), contact angle and mechanical testing measurements. The results revealed that the water-uptake was reduced by increasing the graft percentage. The thermal and mechanical properties were also improved.

Keywords: cellulose acetate, food packaging, graft copolymerization, thermal properties

Procedia PDF Downloads 220
4518 Microkinetic Modelling of NO Reduction on Pt Catalysts

Authors: Vishnu S. Prasad, Preeti Aghalayam

Abstract:

The major harmful automobile exhausts are nitric oxide (NO) and unburned hydrocarbon (HC). Reduction of NO using unburned fuel HC as a reductant is the technique used in hydrocarbon-selective catalytic reduction (HC-SCR). In this work, we study the microkinetic modelling of NO reduction using propene as a reductant on Pt catalysts. The selectivity of NO reduction to N2O is detected in some ranges of operating conditions, whereas the effect of inlet O2% causes a number of changes in the feasible regimes of operation.

Keywords: microkinetic modelling, NOx, platinum on alumina catalysts, selective catalytic reduction

Procedia PDF Downloads 454
4517 Role of SiOx Interlayer on Lead Oxide Electrodeposited on Stainless Steel for Promoting Electrochemical Treatment of Wastewater Containing Textile Dye

Authors: Hanene Akrout, Ines Elaissaoui, Sabrina Grassini, Daniele Fulginiti, Latifa Bousselmi

Abstract:

The main objective of this work is to investigate the efficiency of depollution power related to PbO₂ layer deposited onto a stainless steel (SS) substrate with SiOx as interlayer. The elaborated electrode was used as anode for anodic oxidation of wastewater containing Amaranth dye, as recalcitrant organic pollutant model. SiOx interlayer was performed using Plasma Enhanced Chemical Vapor Deposition ‘PECVD’ in plasma fed with argon, oxygen, and tetraethoxysilane (TEOS, Si precursor) in different ratios, onto the SS substrate. PbO₂ layer was produced by pulsed electrodeposition on SS/SiOx. The morphological of different surfaces are depicted with Field Emission Scanning Electron Microscope (FESEM) and the composition of the lead oxide layer was investigated by X-Ray Diffractometry (XRD). The results showed that the SiOx interlayer with more rich oxygen content improved better the nucleation of β-PbO₂ form. Electrochemical Impedance Spectroscopy (EIS) measurements undertaken on different interfaces (at optimized conditions) revealed a decrease of Rfilm while CPE film increases for SiOx interlayer, characterized by a more inorganic nature and deposited in a plasma fed by higher O2-to-TEOS ratios. Quantitative determinations of the Amaranth dye degradation rate were performed in terms of colour and COD removals, reaching a 95% and an 80% respectively removal at pH = 2 in 300 min. Results proved the improvement of the degradation wastewater containing the amaranth dye. During the electrolysis, the Amaranth dye solution was sampled at 30 min intervals and analyzed by ‘High-performance Liquid Chromatography’ HPLC. The gradual degradation of the Amaranth dye confirmed by the decrease in UV absorption using the SS/SiOx(20:20:1)/PbO₂ anode, the reaction exhibited an apparent first-order kinetic for electrolysis time of 5 hours, with an initial rate constant of about 0.02 min⁻¹.

Keywords: electrochemical treatment, PbO₂ anodes, COD removal, plasma

Procedia PDF Downloads 191
4516 Exploring Tree Growth Variables Influencing Carbon Sequestration in the Face of Climate Change

Authors: Funmilayo Sarah Eguakun, Peter Oluremi Adesoye

Abstract:

One of the major problems being faced by human society is that the global temperature is believed to be rising due to human activity that releases carbon IV oxide (CO2) to the atmosphere. Carbon IV oxide is the most important greenhouse gas influencing global warming and possible climate change. With climate change becoming alarming, reducing CO2 in our atmosphere has become a primary goal of international efforts. Forest landsare major sink and could absorb large quantities of carbon if the trees are judiciously managed. The study aims at estimating the carbon sequestration capacity of Pinus caribaea (pine)and Tectona grandis (Teak) under the prevailing environmental conditions and exploring tree growth variables that influencesthe carbon sequestration capacity in Omo Forest Reserve, Ogun State, Nigeria. Improving forest management by manipulating growth characteristics that influences carbon sequestration could be an adaptive strategy of forestry to climate change. Random sampling was used to select Temporary Sample Plots (TSPs) in the study area from where complete enumeration of growth variables was carried out within the plots. The data collected were subjected to descriptive and correlational analyses. The results showed that average carbon stored by Pine and Teak are 994.4±188.3 Kg and 1350.7±180.6 Kg respectively. The difference in carbon stored in the species is significant enough to consider choice of species relevant in climate change adaptation strategy. Tree growth variables influence the capacity of the tree to sequester carbon. Height, diameter, volume, wood density and age are positively correlated to carbon sequestration. These tree growth variables could be manipulated by the forest manager as an adaptive strategy for climate change while plantations of high wood density speciescould be relevant for management strategy to increase carbon storage.

Keywords: adaptation, carbon sequestration, climate change, growth variables, wood density

Procedia PDF Downloads 378
4515 Application of Host Factors as Biomarker in Early Diagnosis of Pulmonary Tuberculosis

Authors: Ambrish Tiwari, Sudhasini Panda, Archana Singh, Kalpana Luthra, S. K. Sharma

Abstract:

Introduction: On the basis of available literature we know that various host factors play a role in outcome of Tuberculosis (TB) infection by modulating innate immunity. One such factor is Inducible Nitric Oxide Synthase enzyme (iNOS) which help in the production of Nitric Oxide (NO), an antimicrobial agent. Expression of iNOS is in control of various host factors in which Vitamin D along with its nuclear receptor Vitamin D receptor (VDR) is one of them. Vitamin D along with its receptor also produces cathelicidin (antimicrobicidal agent). With this background, we attempted to investigate the levels of Vitamin D and NO along with their associated molecules in tuberculosis patients and household contacts as compared to healthy controls and assess the implication of these findings in susceptibility to tuberculosis (TB). Study subjects and methods: 100 active TB patients, 75 household contacts, and 70 healthy controls were taken. VDR and iNOS mRNA levels were studied using real-time PCR. Serum VDR, cathelicidin, iNOS levels were measured using ELISA. Serum Vitamin D levels were measured in serum samples using chemiluminescence based immunoassay. NO was measured using colorimetry based kit. Results: VDR and iNOS mRNA levels were found to be lower in active TB group compared to household contacts and healthy controls (P=0.0001 and 0.005 respectively). The serum levels of Vitamin D were also found to be lower in active TB group as compared to healthy controls (P =0.001). Levels of cathelicidin and NO was higher in patient group as compared to other groups (p=0.01 and 0.5 respectively). However, the expression of VDR and iNOS and levels of vitamin D was significantly (P < 0.05) higher in household contacts compared to both active TB and healthy control groups. Inference: Higher levels of Vitamin D along with VDR and iNOS expression in household contacts as compared to patients suggest that vitamin D might have a protective role against TB which prevents activation of the disease. From our data, we can conclude that decreased vitamin D levels could be implicated in disease progression and we can use cathelicidin and NO as a biomarker for early diagnosis of pulmonary tuberculosis.

Keywords: vitamin D, VDR, iNOS, tuberculosis

Procedia PDF Downloads 302
4514 Process Data-Driven Representation of Abnormalities for Efficient Process Control

Authors: Hyun-Woo Cho

Abstract:

Unexpected operational events or abnormalities of industrial processes have a serious impact on the quality of final product of interest. In terms of statistical process control, fault detection and diagnosis of processes is one of the essential tasks needed to run the process safely. In this work, nonlinear representation of process measurement data is presented and evaluated using a simulation process. The effect of using different representation methods on the diagnosis performance is tested in terms of computational efficiency and data handling. The results have shown that the nonlinear representation technique produced more reliable diagnosis results and outperforms linear methods. The use of data filtering step improved computational speed and diagnosis performance for test data sets. The presented scheme is different from existing ones in that it attempts to extract the fault pattern in the reduced space, not in the original process variable space. Thus this scheme helps to reduce the sensitivity of empirical models to noise.

Keywords: fault diagnosis, nonlinear technique, process data, reduced spaces

Procedia PDF Downloads 245
4513 Effect of Repellent Coatings, Aerosol Protective Liners, and Lamination on the Properties of Chemical/Biological Protective Textiles

Authors: Natalie Pomerantz, Nicholas Dugan, Molly Richards, Walter Zukas

Abstract:

The primary research question to be answered for Chemical/Biological (CB) protective clothing, is how to protect wearers from a range of chemical and biological threats in liquid, vapor, and aerosol form, while reducing the thermal burden. Currently, CB protective garments are hot, heavy, and wearers are limited by short work times in order to prevent heat injury. This study demonstrates how to incorporate different levels of protection on a material level and modify fabric composites such that the thermal burden is reduced to such an extent it approaches that of a standard duty uniform with no CB protection. CB protective materials are usually comprised of several fabric layers: a cover fabric with a liquid repellent coating, a protective layer which is comprised of a carbon-based sorptive material or semi-permeable membrane, and a comfort next-to-skin liner. In order to reduce thermal burden, all of these layers were laminated together to form one fabric composite which had no insulative air gap in between layers. However, the elimination of the air gap also reduced the CB protection of the fabric composite. In order to increase protection in the laminated composite, different nonwoven aerosol protective liners were added, and a super repellent coating was applied to the cover fabric, prior to lamination. Different adhesive patterns were investigated to determine the durability of the laminate with the super repellent coating, and the effect on air permeation. After evaluating the thermal properties, textile properties and protective properties of the iterations of these fabric composites, it was found that the thermal burden of these materials was greatly reduced by decreasing the thermal resistance with the elimination of the air gap between layers. While the level of protection was reduced in laminate composites, the addition of a super repellent coating increased protection towards low volatility agents without impacting thermal burden. Similarly, the addition of aerosol protective liner increased protection without reducing water vapor transport, depending on the nonwoven used, however, the air permeability was significantly decreased. The balance of all these properties and exploration of the trade space between thermal burden and protection will be discussed.

Keywords: aerosol protection, CBRNe protection, lamination, nonwovens, repellent coatings, thermal burden

Procedia PDF Downloads 361
4512 Magnetic Properties of Nickel Oxide Nanoparticles in Superparamagnetic State

Authors: Navneet Kaur, S. D. Tiwari

Abstract:

Superparamagnetism is an interesting phenomenon and observed in small particles of magnetic materials. It arises due to a reduction in particle size. In the superparamagnetic state, as the thermal energy overcomes magnetic anisotropy energy, the magnetic moment vector of particles flip their magnetization direction between states of minimum energy. Superparamagnetic nanoparticles have been attracting the researchers due to many applications such as information storage, magnetic resonance imaging, biomedical applications, and sensors. For information storage, thermal fluctuations lead to loss of data. So that nanoparticles should have high blocking temperature. And to achieve this, nanoparticles should have a higher magnetic moment and magnetic anisotropy constant. In this work, the magnetic anisotropy constant of the antiferromagnetic nanoparticles system is determined. Magnetic studies on nanoparticles of NiO (nickel oxide) are reported well. This antiferromagnetic nanoparticle system has high blocking temperature and magnetic anisotropy constant of order 105 J/m3. The magnetic study of NiO nanoparticles in the superparamagnetic region is presented. NiO particles of two different sizes, i.e., 6 and 8 nm, are synthesized using the chemical route. These particles are characterized by an x-ray diffractometer, transmission electron microscope, and superconducting quantum interference device magnetometry. The magnetization vs. applied magnetic field and temperature data for both samples confirm their superparamagnetic nature. The blocking temperature for 6 and 8 nm particles is found to be 200 and 172 K, respectively. Magnetization vs. applied magnetic field data of NiO is fitted to an appropriate magnetic expression using a non-linear least square fit method. The role of particle size distribution and magnetic anisotropy is taken in to account in magnetization expression. The source code is written in Python programming language. This fitting provides us the magnetic anisotropy constant for NiO and other magnetic fit parameters. The particle size distribution estimated matches well with the transmission electron micrograph. The value of magnetic anisotropy constants for 6 and 8 nm particles is found to be 1.42 X 105 and 1.20 X 105 J/m3, respectively. The obtained magnetic fit parameters are verified using the Neel model. It is concluded that the effect of magnetic anisotropy should not be ignored while studying the magnetization process of nanoparticles.

Keywords: anisotropy, superparamagnetic, nanoparticle, magnetization

Procedia PDF Downloads 131
4511 Arginase Enzyme Activity in Human Serum as a Marker of Cognitive Function: The Role of Inositol in Combination with Arginine Silicate

Authors: Katie Emerson, Sara Perez-Ojalvo, Jim Komorowski, Danielle Greenberg

Abstract:

The purpose of this study was to evaluate arginase activity levels in response to combinations of an inositol-stabilized arginine silicate (ASI; Nitrosigine®), L-arginine, and Inositol. Arginine acts as a vasodilator that promotes increased blood flow resulting in enhanced delivery of oxygen and nutrients to the brain and other tissues. ASI alone has been shown to improve performance on cognitive tasks. Arginase, found in human serum, catalyzes the conversion of arginine to ornithine and urea, completing the last step in the urea cycle. Decreasing arginase levels maintains arginine and results in increased nitric oxide production. This study aimed to determine the most effective combination of ASI, L-arginine and inositol for minimizing arginase levels and therefore maximize ASI’s effect on cognition. Serum was taken from untreated healthy donors by separation from clotted factors. Arginase activity of serum in the presence or absence of test products was determined (QuantiChrom™, DARG-100, Bioassay Systems, Hayward CA). The remaining ultra-filtrated serum units were harvested and used as the source for the arginase enzyme. ASI alone or combined with varied levels of Inositol were tested as follows: ASI + inositol at 0.25 g, 0.5 g, 0.75 g, or 1.00 g. L-arginine was also tested as a positive control. All tests elicited changes in arginase activity demonstrating the efficacy of the method used. Adding L-arginine to serum from untreated subjects, with or without inositol only had a mild effect. Adding inositol at all levels reduced arginase activity. Adding 0.5 g to the standardized amount of ASI led to the lowest amount of arginase activity as compared to the 0.25g 0.75g or 1.00g doses of inositol or to L-arginine alone. The outcome of this study demonstrates an interaction of the pairing of inositol with ASI on the activity of the enzyme arginase. We found that neither the maximum nor minimum amount of inositol tested in this study led to maximal arginase inhibition. Since the inhibition of arginase activity is desirable for product formulations looking to maintain arginine levels, the most effective amount of inositol was deemed preferred. Subsequent studies suggest this moderate level of inositol in combination with ASI leads to cognitive improvements including reaction time, executive function, and concentration.

Keywords: arginine, inositol, arginase, cognitive benefits

Procedia PDF Downloads 111
4510 Studies on Structural and Electrical Properties of Lanthanum Doped Sr₂CoMoO₆₋δ System

Authors: Pravin Kumar, Rajendra K. Singh, Prabhakar Singh

Abstract:

A widespread research work on Mo-based double perovskite systems has been reported as a potential application for electrode materials of solid oxide fuel cells. Mo-based double perovskites studied in form of B-site ordered double perovskite materials, with general formula A₂B′B″O₆ structured by alkaline earth element (A = Sr, Ca, Ba) and heterovalent transition metals (B′ = Fe, Co, Ni, Cr, etc. and B″ = Mo, W, etc.), are raising a significant interest as potential mixed ionic-electronic conductors in the temperature range of 500-800 °C. Such systems reveal higher electrical conductivity, particularly those assigned in form of Sr₂CoMoO₆₋δ (M = Mg, Mn, Fe, Co, Ni, Zn etc.) which were studied in different environments (air/H₂/H₂-Ar/CH₄) at an intermediate temperature. Among them, the Sr₂CoMoO₆₋δ system is a potential candidate as an anode material for solid oxide fuel cells (SOFCs) due to its better electrical conductivity. Therefore, Sr₂CoMoO₆₋δ (SCM) system with La-doped on Sr site has been studied to discover the structural and electrical properties. The double perovskite system Sr₂CoMoO₆₋δ (SCM) and doped system Sr₂-ₓLaₓCoMoO₆₋δ (SLCM, x=0.04) were synthesized by the citrate-nitrate combustion synthesis route. Thermal studies were carried out by thermo-gravimetric analysis. Phase justification was confirmed by powder X-ray diffraction (XRD) as a tetragonal structure with space group I4/m. A minor phase of SrMoO₄ (s.g. I41/a) was identified as a secondary phase using JCPDS card no. 85-0586. Micro-structural investigations revealed the formation of uniform grains. The average grain size of undoped (SCM) and doped (SLCM) compositions was calculated by a linear intercept method and found to be ⁓3.8 μm and 2.7 μm, respectively. The electrical conductivity of SLCM is found higher than SCM in the air within the temperature range of 200-600 °C. SLCM system was also measured in reducing atmosphere (pure H₂) in the temperature range 300-600 °C. SLCM has been showed the higher conductivity in the reducing atmosphere (H₂) than in air and therefore it could be a promising anode material for SOFCs.

Keywords: double perovskite, electrical conductivity, SEM, XRD

Procedia PDF Downloads 131
4509 Application of Grasshopper Optimization Algorithm for Design and Development of Net Zero Energy Residential Building in Ahmedabad, India

Authors: Debasis Sarkar

Abstract:

This paper aims to apply the Grasshopper-Optimization-Algorithm (GOA) for designing and developing a Net-Zero-Energy residential building for a mega-city like Ahmedabad in India. The methodology implemented includes advanced tools like Revit for model creation and MATLAB for simulation, enabling the optimization of the building design. GOA has been applied in reducing cooling loads and overall energy consumption through optimized passive design features. For the attainment of a net zero energy mission, solar panels were installed on the roof of the building. It has been observed that the energy consumption of 8490 kWh was supported by the installed solar panels. Thereby only 840kWh had to be supported by non-renewable energy sources. The energy consumption was further reduced through the application of simulation and optimization methods like GOA, which further reduced the energy consumption to about 37.56 kWh per month from April to July when energy demand was at its peak. This endeavor aimed to achieve near-zero-energy consumption, showcasing the potential of renewable energy integration in building sustainability.

Keywords: grasshopper optimization algorithm, net zero energy, residential building, sustainable design

Procedia PDF Downloads 36
4508 Architectural Adaptation for Road Humps Detection in Adverse Light Scenario

Authors: Padmini S. Navalgund, Manasi Naik, Ujwala Patil

Abstract:

Road hump is a semi-cylindrical elevation on the road made across specific locations of the road. The vehicle needs to maneuver the hump by reducing the speed to avoid car damage and pass over the road hump safely. Road Humps on road surfaces, if identified in advance, help to maintain the security and stability of vehicles, especially in adverse visibility conditions, viz. night scenarios. We have proposed a deep learning architecture adaptation by implementing the MISH activation function and developing a new classification loss function called "Effective Focal Loss" for Indian road humps detection in adverse light scenarios. We captured images comprising of marked and unmarked road humps from two different types of cameras across South India to build a heterogeneous dataset. A heterogeneous dataset enabled the algorithm to train and improve the accuracy of detection. The images were pre-processed, annotated for two classes viz, marked hump and unmarked hump. The dataset from these images was used to train the single-stage object detection algorithm. We utilised an algorithm to synthetically generate reduced visible road humps scenarios. We observed that our proposed framework effectively detected the marked and unmarked hump in the images in clear and ad-verse light environments. This architectural adaptation sets up an option for early detection of Indian road humps in reduced visibility conditions, thereby enhancing the autonomous driving technology to handle a wider range of real-world scenarios.

Keywords: Indian road hump, reduced visibility condition, low light condition, adverse light condition, marked hump, unmarked hump, YOLOv9

Procedia PDF Downloads 21
4507 Bio-Nanotechnology Approach of Nano-Size Iron Particles as Promising Iron Supplements: An Exploratory Study to Combat the Problems of Iron Fortification in Children and Pregnant Women of Rural India

Authors: Roshni Raha, Kavya P., Gayathri M.

Abstract:

India, with a humongous population, remains the world's poorest developing nation in terms of nutritional status, with iron deficiency anaemia (IDA) affecting the population. Despite efforts over the past decades, India's anaemia prevalence has not been reduced. Researchers are interested in developing therapies that will minimize the typical side effects of oral iron and optimize iron salts-based treatment through delivery methods based on the physiology of hepcidin regulation. However, they need to come up with iron therapies that will prevent making the infection worse. This article explores using bio-nanotechnology as the alternative, promising substitution of providing iron supplements for the treatment of diarrhoea and gut inflammation in kids and pregnant women. This article is an exploratory study using a literature survey and secondary research from review papers. In the realm of biotechnology, nanoparticles have become extremely famous due to unexpected variations in surface characteristics caused by particle size. Particle size distribution and shape exhibit unusual, enhanced characteristics when reduced to nanoscale. The article attempts to develop a model for a nanotechnology based solution in iron fortification to combat the problems of diarrhoea and gut inflammation. Certain dimensions that have been considered in the model include the size, shape, source, and biosynthesis of the iron nanoparticles. Another area of investigation addressed in the article is the cost-effective biocompatible production of these iron nanoparticles. Studies have demonstrated that a substantial reduction of metal ions to form nanoparticles from the bulk metal occurs in plants because of the presence of a wide diversity of biomolecules. Using this concept, the paper investigates the effectiveness and impact of how similar sources can be used for the biological synthesis of iron nanoparticles. Results showed that iron particles, when prepared in nano-metre size, offer potential advantages. When the particle size of the iron compound decreases and attains nano configuration, its surface area increases, which further improves its solubility in the gastric acid, leading to higher absorption, higher bioavailability, and producing the least organoleptic changes in food. It has no negative effects and possesses a safe, effective profile to reduce IDA. Considering all the parameters, it has been concluded that iron particles in nano configuration serve as alternative iron supplements for the complete treatment of IDA. Nanoparticles of ferric phosphate, ferric pyrophosphate, and iron oxide are the choices of iron supplements. From a sourcing perspective, the paper concludes green sources are the primary sources for the biological synthesis of iron nanoparticles. It will also be a cost-effective strategy since our goal is to treat the target population in rural India. Bio-nanotechnology serves as an alternative and promising substitution for iron supplements due to its low cost, excellent bioavailability, and strong organoleptic properties. One area of future research can be to explore the type of size and shape of iron nanoparticles that would be suitable for the different age groups of pregnant women and children and whether it would be influenced based on the topography in certain areas.

Keywords: anemia, bio-nanotechnology, iron-fortification, nanoparticle

Procedia PDF Downloads 75
4506 Stabilization of Pb, Cr, Cd, Cu and Zn in Solid Waste and Sludge Pyrolysis by Modified Vermiculite

Authors: Yuxuan Yang, Zhaoping Zhong

Abstract:

Municipal solid waste and sludge are important sources of waste energy and their proper disposal is of great importance. Pyrolysis can fully decompose solid wastes and sludge, and the pyrolysis products (charcoal, oil and gas) have important recovery values. Due to the complex composition of solid wastes and sludge, the pyrolysis process at high temperatures is prone to heavy metal emissions, which are harmful to humans and the environment and reduce the safety of pyrolysis products. In this paper, heavy metal emissions during pyrolysis of municipal sewage sludge, paper mill sludge, municipal domestic waste, and aged refuse at 450-650°C were investigated and the emissions and hazards of heavy metals (Pb, Cr, Cd, Cu and Zn) were effectively reduced by adding modified vermiculite as an additive. The vermiculite was modified by intercalation with cetyltrimethylammonium bromide, which resulted in more than twice the original layer spacing of the vermiculite. Afterward, the interpolated vermiculite was made into vermiculite flakes by exfoliation modification. After that, the expansion rate of vermiculite flakes was increased by Mg2+ modification and thermal activation. The expanded vermiculite flakes were acidified to improve the textural characteristics of the vermiculite. The modified vermiculite was analysed by XRD, FT-IR, BET and SEM to clarify the modification effect. The incorporation of modified vermiculite resulted in more than 80% retention of all heavy metals at 450°C. Cr, Cu and Zn were better retained than Pb and Cd. The incorporation of modified vermiculite effectively reduced the risk of heavy metals, and all risks were low for Pb, Cr, Cu and Zn. The toxicity of all heavy metals was greatly reduced by the incorporation of modified vermiculite and the morphology of heavy metals was transformed from Exchangeable and acid-soluble (F1) and Reducible (F2) to Oxidizable (F3) and Residual (F4). In addition, the increase in temperature favored the stabilization of heavy metal forms. This study provides a new insight into the cleaner use of energy and the safe management of solid waste.

Keywords: heavy metal, pyrolysis, vermiculite, solid waste

Procedia PDF Downloads 67
4505 Stabilization of Lateritic Soil Sample from Ijoko with Cement Kiln Dust and Lime

Authors: Akinbuluma Ayodeji Theophilus, Adewale Olutaiwo

Abstract:

When building roads and paved surfaces, a strong foundation is always essential. A durable material that can withstand years of traffic while staying trustworthy must be used to build the foundation. A frequent problem in the construction of roads and pavements is the lack of high-quality, long-lasting materials for the pavement structure (base, subbase, and subgrade). Hence, this study examined the stabilization of lateritic soil samples from Ijoko with cement kiln dust and lime. The study adopted the experimental design. Laboratory tests were conducted on classification, swelling potential, compaction, California bearing ratio (CBR), and unconfined compressive tests, among others, were conducted on the laterite sample treated with cement kiln dust (CKD) and lime in incremental order of 2% up to 10% of dry weight soft soil sample. The results of the test showed that the studied soil could be classified as an A-7-6 and CL soil using the American Association of State Highway and transport officials (AASHTO) and the unified soil classification system (USCS), respectively. The plasticity (PI) of the studied soil reduced from 30.5% to 29.9% at the application of CKD. The maximum dry density on the application of CKD reduced from 1.9.7 mg/m3 to 1.86mg/m3, and lime application yielded a reduction from 1.97mg/m3 to 1.88.mg/m3. The swell potential on CKD application was reduced from 0.05 to 0.039%. The study concluded that soil stabilizations are effective and economic way of improving road pavement for engineering benefit. The degree of effectiveness of stabilization in pavement construction was found to depend on the type of soil to be stabilized. The study therefore recommended that stabilized soil mixtures should be used to subbase material for flexible pavement since is a suitable.

Keywords: lateritic soils, sand, cement, stabilization, road pavement

Procedia PDF Downloads 87
4504 The Creative Unfolding of “Reduced Descriptive Structures” in Musical Cognition: Technical and Theoretical Insights Based on the OpenMusic and PWGL Long-Term Feedback

Authors: Jacopo Baboni Schilingi

Abstract:

We here describe the theoretical and philosophical understanding of a long term use and development of algorithmic computer-based tools applied to music composition. The findings of our research lead us to interrogate some specific processes and systems of communication engaged in the discovery of specific cultural artworks: artistic creation in the sono-musical domain. Our hypothesis is that the patterns of auditory learning cannot be only understood in terms of social transmission but would gain to be questioned in the way they rely on various ranges of acoustic stimuli modes of consciousness and how the different types of memories engaged in the percept-action expressive systems of our cultural communities also relies on these shadowy conscious entities we named “Reduced Descriptive Structures”.

Keywords: algorithmic sonic computation, corrected and self-correcting learning patterns in acoustic perception, morphological derivations in sensorial patterns, social unconscious modes of communication

Procedia PDF Downloads 153
4503 Infused Mesenchymal Stem Cells Ameliorate Organs Morphology in Cerebral Malaria Infection

Authors: Reva Sharan Thakur, Mrinalini Tiwari, Jyoti das

Abstract:

Cerebral malaria-associated over expression of pro-inflammatory cytokines and chemokines ultimately results in the up-regulation of adhesion molecules in the brain endothelium leading to sequestration of mature parasitized RBCs in the brain. The high-parasitic load subsequently results in increased mortality or development of neurological symptoms within a week of infection. Studies in the human and experimental cerebral malaria have implicated the breakdown of the integrity of blood-brain barrier during the lethal course of infection, cerebral dysfunction, and fatal organ pathologies that result in multi-organ failure. In the present study, using Plasmodium berghei Anka as a mouse model and in vitro conditions, we have investigated the effect of MSCs to attenuate cerebral malaria pathogenesis by diminishing the effect of inflammation altered organ morphology, reduced parasitemia, and increased survival of the mice. MSCs are also validated for their role in preventing BBB dysfunction and reducing malarial toxins. It was observed that administration of MSCs significantly reduced parasitemia and increased survival in Pb A infected mice. It was further demonstrated that MSCs play a significant role in reversing neurological complexities associated with cerebral malaria. Infusion of MSCs in infected mice decreased hemozoin deposition; oedema, and haemorrhagic lesions in vascular organs. MSCs administration also preserved the integrity of the blood-brain barrier and reduced neural inflammation. Taken together, our results demonstrate the potential of MSCs as an emerging anti-malarial candidate.

Keywords: cerebral malaria, mesenchymal stem cells, erythropoesis, cell death

Procedia PDF Downloads 102
4502 Microporous 3D Aluminium Metal-Organic Frameworks in Chitosan Based Mixed Matrix Membrane for Ethanol/Water Separation

Authors: Madhan Vinu, Yue-Chun Jiang, Yi-Feng Lin, Chia-Her Lin

Abstract:

An effective approach to enhance the ethanol/water pervaporation of mixed matrix membranes prepared from three microporous aluminium based metal-organic frameworks (MOFs), [Al(OH)(BPDC)] (DUT-5), [Al(OH)(NDC)] (DUT-4) and [Al(OH)(BzPDC)] (CAU-8) have been synthesized by employing solvothermal reactions. Interestingly, all Al-MOFs showed attractive surface area with microporous 12.3, 10.2 and 8.0 Å for DUT-5, DUT-4 and CAU-8 MOFs which are confirmed through N₂ gas sorption measurements. All the microporous compounds are highly stable as confirmed by thermogravimetric analysis and temperature-dependent powder X-ray diffraction measurements. Furthermore, the synthesized microporous MOF particles of DUT-5, DUT-4, and CAU-8 were successfully incorporated into biological chitosan (CS) membranes to form DUT-5@CS, DUT-4@CS, and CAU-8@CS membranes. The different MOF loadings such as 0.1, 0.15, and 0.2 wt% in CS networks have been prepared, and the same were used to separate mixtures of water and ethanol at 25ºC in the pervaporation process. In particular, when 0.15 wt% of DUT-5 was loaded, MOF@CS membrane displayed excellent permeability and selectivity in ethanol/water separation than that of the previous literature. These CS based membranes separation through functionalized microporous MOFs reveals the key governing factors that are essential for designing novel MOF membranes for bioethanol purification.

Keywords: metal-organic framework, microporous materials, separation, chitosan membranes

Procedia PDF Downloads 219
4501 Li2o Loss of Lithium Niobate Nanocrystals during High-Energy Ball-Milling

Authors: Laura Kocsor, Laszlo Peter, Laszlo Kovacs, Zsolt Kis

Abstract:

The aim of our research is to prepare rare-earth-doped lithium niobate (LiNbO3) nanocrystals, having only a few dopant ions in the focal point of an exciting laser beam. These samples will be used to achieve individual addressing of the dopant ions by light beams in a confocal microscope setup. One method for the preparation of nanocrystalline materials is to reduce the particle size by mechanical grinding. High-energy ball-milling was used in several works to produce nano lithium niobate. Previously, it was reported that dry high-energy ball-milling of lithium niobate in a shaker mill results in the partial reduction of the material, which leads to a balanced formation of bipolarons and polarons yielding gray color together with oxygen release and Li2O segregation on the open surfaces. In the present work we focus on preparing LiNbO3 nanocrystals by high-energy ball-milling using a Fritsch Pulverisette 7 planetary mill. Every ball-milling process was carried out in zirconia vial with zirconia balls of different sizes (from 3 mm to 0.1 mm), wet grinding with water, and the grinding time being less than an hour. Gradually decreasing the ball size to 0.1 mm, an average particle size of about 10 nm could be obtained determined by dynamic light scattering and verified by scanning electron microscopy. High-energy ball-milling resulted in sample darkening evidenced by optical absorption spectroscopy measurements indicating that the material underwent partial reduction. The unwanted lithium oxide loss decreases the Li/Nb ratio in the crystal, strongly influencing the spectroscopic properties of lithium niobate. Zirconia contamination was found in ground samples proved by energy-dispersive X-ray spectroscopy measurements; however, it cannot be explained based on the hardness properties of the materials involved in the ball-milling process. It can be understood taking into account the presence of lithium hydroxide formed the segregated lithium oxide and water during the ball-milling process, through chemically induced abrasion. The quantity of the segregated Li2O was measured by coulometric titration. During the wet milling process in the planetary mill, it was found that the lithium oxide loss increases linearly in the early phase of the milling process, then a saturation of the Li2O loss can be seen. This change goes along with the disappearance of the relatively large particles until a relatively narrow size distribution is achieved in accord with the dynamic light scattering measurements. With the 3 mm ball size and 1100 rpm rotation rate, the mean particle size achieved is 100 nm, and the total Li2O loss is about 1.2 wt.% of the original LiNbO3. Further investigations have been done to minimize the Li2O segregation during the ball-milling process. Since the Li2O loss was observed to increase with the growing total surface of the particles, the influence of ball-milling parameters on its quantity has also been studied.

Keywords: high-energy ball-milling, lithium niobate, mechanochemical reaction, nanocrystals

Procedia PDF Downloads 133
4500 Calibration of Discrete Element Method Parameters for Modelling DRI Pellets Flow

Authors: A. Hossein Madadi-Najafabadi, Masoud Nasiri

Abstract:

The discrete element method is a powerful technique for numerical modeling the flow of granular materials such as direct reduced iron. It would enable us to study processes and equipment related to the production and handling of the material. However, the characteristics and properties of the granules have to be adjusted precisely to achieve reliable results in a DEM simulation. The main properties for DEM simulation are size distribution, density, Young's modulus, Poisson's ratio and the contact coefficients of restitution, rolling friction and sliding friction. In the present paper, the mentioned properties are determined for DEM simulation of DRI pellets. A reliable DEM simulation would contribute to optimizing the handling system of DRIs in an iron-making plant. Among the mentioned properties, Young's modulus is the most important parameter, which is usually hard to get for particulate solids. Here, an especial method is utilized to precisely determine this parameter for DRI.

Keywords: discrete element method, direct reduced iron, simulation parameters, granular material

Procedia PDF Downloads 179
4499 Charge Transport of Individual Thermoelectric Bi₂Te₃ Core-Poly(3,4-Ethylenedioxythiophene):Polystyrenesulfonate Shell Nanowires Determined Using Conductive Atomic Force Microscopy and Spectroscopy

Authors: W. Thongkham, K. Sinthiptharakoon, K. Tantisantisom, A. Klamchuen, P. Khanchaitit, K. Jiramitmongkon, C. Lertsatitthanakorn, M. Liangruksa

Abstract:

Due to demands of sustainable energy, thermoelectricity converting waste heat into electrical energy has become one of the intensive fields of worldwide research. However, such harvesting technology has shown low device performance in the temperature range below 150℃. In this work, a hybrid nanowire of inorganic bismuth telluride (Bi₂Te₃) and organic poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) synthesized using a simple in-situ one-pot synthesis, enhancing efficiency of the nanowire-incorporated PEDOT:PSS-based thermoelectric converter is highlighted. Since the improvement is ascribed to the increased electrical conductivity of the thermoelectric host material, the individual hybrid nanowires are investigated using voltage-dependent conductive atomic force microscopy (CAFM) and spectroscopy (CAFS) considering that the electrical transport measurement can be performed either on insulating or conducting areas of the sample. Correlated with detailed chemical information on the crystalline structure and compositional profile of the nanowire core-shell structure, an electrical transporting pathway through the nanowire and the corresponding electronic-band structure have been determined, in which the native oxide layer on the Bi₂Te₃ surface is not considered, and charge conduction on the topological surface states of Bi₂Te₃ is suggested. Analyzing the core-shell nanowire synthesized using the conventional mixing of as-prepared Bi₂Te₃ nanowire with PEDOT:PSS for comparison, the oxide-removal effect of the in-situ encapsulating polymeric layer is further supported. The finding not only provides a structural information for mechanistic determination of the thermoelectricity, but it also encourages new approach toward more appropriate encapsulation and consequently higher efficiency of the nanowire-based thermoelectric generation.

Keywords: electrical transport measurement, hybrid Bi₂Te₃-PEDOT:PSS nanowire, nanoencapsulation, thermoelectricity, topological insulator

Procedia PDF Downloads 203
4498 Colloid-Based Biodetection at Aqueous Electrical Interfaces Using Fluidic Dielectrophoresis

Authors: Francesca Crivellari, Nicholas Mavrogiannis, Zachary Gagnon

Abstract:

Portable diagnostic methods have become increasingly important for a number of different purposes: point-of-care screening in developing nations, environmental contamination studies, bio/chemical warfare agent detection, and end-user use for commercial health monitoring. The cheapest and most portable methods currently available are paper-based – lateral flow and dipstick methods are widely available in drug stores for use in pregnancy detection and blood glucose monitoring. These tests are successful because they are cheap to produce, easy to use, and require minimally invasive sampling. While adequate for their intended uses, in the realm of blood-borne pathogens and numerous cancers, these paper-based methods become unreliable, as they lack the nM/pM sensitivity currently achieved by clinical diagnostic methods. Clinical diagnostics, however, utilize techniques involving surface plasmon resonance (SPR) and enzyme-linked immunosorbent assays (ELISAs), which are expensive and unfeasible in terms of portability. To develop a better, competitive biosensor, we must reduce the cost of one, or increase the sensitivity of the other. Electric fields are commonly utilized in microfluidic devices to manipulate particles, biomolecules, and cells. Applications in this area, however, are primarily limited to interfaces formed between immiscible interfaces. Miscible, liquid-liquid interfaces are common in microfluidic devices, and are easily reproduced with simple geometries. Here, we demonstrate the use of electrical fields at liquid-liquid electrical interfaces, known as fluidic dielectrophoresis, (fDEP) for biodetection in a microfluidic device. In this work, we apply an AC electric field across concurrent laminar streams with differing conductivities and permittivities to polarize the interface and induce a discernible, near-immediate, frequency-dependent interfacial tilt. We design this aqueous electrical interface, which becomes the biosensing “substrate,” to be intelligent – it “moves” only when a target of interest is present. This motion requires neither labels nor expensive electrical equipment, so the biosensor is inexpensive and portable, yet still capable of sensitive detection. Nanoparticles, due to their high surface-area-to-volume ratio, are often incorporated to enhance detection capabilities of schemes like SPR and fluorimetric assays. Most studies currently investigate binding at an immobilized solid-liquid or solid-gas interface, where particles are adsorbed onto a planar surface, functionalized with a receptor to create a reactive substrate, and subsequently flushed with a fluid or gas with the relevant analyte. These typically involve many preparation and rinsing steps, and are susceptible to surface fouling. Our microfluidic device is continuously flowing and renewing the “substrate,” and is thus not subject to fouling. In this work, we demonstrate the ability to electrokinetically detect biomolecules binding to functionalized nanoparticles at liquid-liquid interfaces using fDEP. In biotin-streptavidin experiments, we report binding detection limits on the order of 1-10 pM, without amplifying signals or concentrating samples. We also demonstrate the ability to detect this interfacial motion, and thus the presence of binding, using impedance spectroscopy, allowing this scheme to become non-optical, in addition to being label-free.

Keywords: biodetection, dielectrophoresis, microfluidics, nanoparticles

Procedia PDF Downloads 387
4497 Non-Steroidal Anti-inflammatory Drugs, Plant Extracts, and Characterized Microparticles to Modulate Antimicrobial Resistance of Epidemic Meca Positive S. Aureus of Dairy Origin

Authors: Amjad I. Aqib, Shanza R. Khan, Tanveer Ahmad, Syed A. R. Shah, Muhammad A. Naseer, Muhammad Shoaib, Iqra Sarwar, Muhammad F. A. Kulyar, Zeeshan A. Bhutta, Mumtaz A. Khan, Mahboob Ali, Khadija Yasmeen

Abstract:

The current study focused on resistance modulation of dairy linked epidemic mec A positive S. aureus for resistance modulation by plant extract (Eucalyptus globolus, Calotropis procera), NSAIDs, and star like microparticles. Zinc oxide {ZnO}c and {Zn (OH)₂} microparticles were synthesized by solvothermal method and characterized by calcination, X-ray diffraction (XRD), and scanning electron microscope (SEM). Plant extracts were prepared by the Soxhlet extraction method. The study found 34% of subclinical samples (n=200) positive for S. aureus from dairy milk having significant (p < 0.05) association of assumed risk factors with pathogen. The antimicrobial assay showed 55, 42, 41, and 41% of S. aureus resistant to oxacillin, ciprofloxacin, streptomycin, and enoxacin. Amoxicillin showed the highest percentage of increase in zone of inhibitions (ZOI) at 100mg of Calotropis procera extract (31.29%) followed by 1mg/mL (28.91%) and 10mg/mL (21.68%) of Eucalyptus globolus. Amoxicillin increased ZOI by 42.85, 37.32, 29.05, and 22.78% in combination with 500 ug/ml with each of diclofenac, aspirin, ibuprofen, and meloxicam, respectively. Fractional inhibitory concentration indices (FICIs) showed synergism of amoxicillin with diclofenac and aspirin and indifferent synergy with ibuprofen and meloxicam. The preliminary in vitro finding of combination of microparticles with amoxicillin proved to be synergistic, giving rise to 26.74% and 14.85% increase in ZOI of amoxicillin in combination with zinc oxide and zinc hydroxide, respectively. The modulated antimicrobial resistance incurred by NSAIDs, plant extracts, and microparticles against pathogenic S. aureus invite immediate attention to probe alternative antimicrobial sources.

Keywords: antimicrobial resistance, dairy milk, nanoparticles, NSIDs, plant extracts, resistance modulation, S. aureus

Procedia PDF Downloads 210
4496 Synthesis of Star Compounds Bearing a Porphyrin Core and Cholic Acid Units by Using Click Chemistry: Study of the Optical Properties and Aggregation

Authors: Edgar Aguilar-Ortíz, Nicolas Lévaray, Mireille Vonlanthen, Eric G. Morales-Espinoza, Ernesto Rivera, Xiao Xia Zhu

Abstract:

Four new star compounds bearing a porphyrin core and cholic acid units, (TPPh(Zn) tetra-CA, TPPh(2H) tetra-CA, TPPh(Zn) octa-CA and TPPh(2H) octa-CA), have been synthesized using the Click Chemistry approach, which consist on azide-alkyne couplings. These novel functionalized porphyrins were characterized by 1H and 13C NMR spectroscopy and their structure was confirmed by MALDI-TOF. The optical properties of these compounds were studied by absorption and fluorescence spectroscopy. On the other hand, order to evaluate the amphiphilic properties of the cholic acid units combined with the optical response of the porphyrin core, we performed absorption and fluorescence studies in function of the polarity of the environment. It was found that as soon as we increase the polarity of the solvent, the Zn-metallated porphyrins, (TPPh(Zn) tetra-CA and TPPh(Zn) octa-CA), are able to form J aggregates, whereas the free-base porphyrins, TPPh(2H) tetra-CA and TPPh(2H) octa-CA, behaved differently.

Keywords: aggregates, amphiphilic, cholic acid, click-chemistry, porphyrin

Procedia PDF Downloads 302
4495 Cr³⁺/SiO₄⁴⁻ Codoped Hydroxyapatite Nanorods: Fabrication and Microstructure Analysis

Authors: Ammar Z. Alshemary, Zafer Evis

Abstract:

In this study, nanorods of Cr³⁺/SiO₄⁴⁻ codoped hydroxyapatite (Cr³⁺/SiO₄⁴⁻-HA) were synthesized successfully and rapidly through microwave irradiation technique, using (Ca(NO₃)₂•4H₂O), ((NH₄)₂HPO₄), (SiC₈H₂₀O₄) and (Cr(NO₃)₃.9H₂O) as source materials for Ca²⁺, PO₄³⁻, SiO₄⁴⁻ and Cr³⁺ ions, respectively. The impact of dopants on the phase formation and microstructure of the powders were investigated by means of X-ray diffraction (XRD), Fourier transform infrared spectrum analysis (FT-IR) and Field emission electron microscopy (FESEM) techniques. XRD analysis showed that with an incorporation of Cr³⁺/SiO₄⁴⁻ ions into HA structure resulted in peak broadening and reduced peak height due to the amorphous nature and reduced crystallinity of the resulting HA powder. FTIR spectroscopy revealed the existence of the different vibrational modes matching to phosphates and hydroxyl groups. The FESEM analysis showed a change in the crystal shape from spherical to rod shaped particles upon Cr³⁺ doping into the crystal structure. Acknowledgments: This study was supported by Karabük University (Project no. KBÜBAP-17-YD-144). The authors would like to thank for support.

Keywords: nano-hydroxyapatite, microwave, dopants, characterization, microstructure

Procedia PDF Downloads 224
4494 Eco-Friendly Synthesis of Carbon Quantum Dots as an Effective Adsorbent

Authors: Hebat‑Allah S. Tohamy, Mohamed El‑Sakhawy, Samir Kamel

Abstract:

Fluorescent carbon quantum dots (CQDs) were prepared by an economical, green, and single-step procedure based on microwave heating of urea with sugarcane bagasse (SCB), cellulose (C), or carboxymethyl cellulose (CMC). The prepared CQDs were characterized using a series of spectroscopic techniques, and they had small size, strong absorption in the UV, and excitation wavelength-dependent fluorescence. The prepared CQDs were used for Pb(II) adsorption from an aqueous solution. The removal efficiency percentages (R %) were 99.16, 96.36, and 98.48 for QCMC, QC, and QSCB. The findings validated the efficiency of CQDs synthesized from CMC, cellulose, and SCB as excellent materials for further utilization in the environmental fields of wastewater pollution detection, adsorption, and chemical sensing applications. The kinetics and isotherms studied found that all CQD isotherms fit well with the Langmuir model than Freundlich and Temkin models. According to R², the pseudo-second-order fits the adsorption of QCMC, while the first-order one fits with QC and QSCB.

Keywords: carbon quantum dots, graphene quantum dots, fluorescence, quantum yield, water treatment, agricultural wastes

Procedia PDF Downloads 130
4493 Parsonage Turner Syndrome PTS, Case Report

Authors: A. M. Bumbea, A. Musetescu, P. Ciurea, A. Bighea

Abstract:

Objectives: The authors present a Parsonage Turner syndrome, a rare disease characterized by onset in apparently healthy person with shoulder and/or arm pain, sensory deficit, motor deficit. The causes are not established, could be determinate by vaccination, postoperative, immunologic disease, post traumatic etc. Methods: The authors present a woman case, 32 years old, (in 2006), no medical history, with arm pain and no other symptom. The onset was sudden with pain at very high level quantified as 10 to a 0 to 10 scale, with no response to classical analgesic and corticoids. The only drugs which can reduce the intensity of pain were oxycodone hydrochloride, 60 mg daily and pregabalinum150 mg daily. After two weeks the intensity of pain was reduced to 5. The patient started a rehabilitation program. After 6 weeks the patient associated sensory and motor deficit. We performed electromyography for upper limb that showed incomplete denervation with reduced neural transmission speed. The patient receives neurotrophic drugs and painkillers for a long period and physical and kinetic therapy. After 6 months the pain was reduced to level 2 and the patient maintained only 150 mg pregabalinum for another 6 months. Then, the evaluation showed no pain but general amiotrophy in upper limb. Results: At the evaluation in 2009, the patient developed a rheumatoid syndrome with tender and swelling joints, but no positive inflammation test, no antibodies or rheumatoid factor. After two years, in 2011 the patient develops an increase of antinuclear antibodies. This context certifies the diagnosis of lupus and the patient receives the specific therapy. Conclusions: This case is not a typical case of onset of lupus with PTS, but the onset of PTS could include the onset of an immune disease.

Keywords: lupus, arm pain, patient, swelling

Procedia PDF Downloads 329