Search results for: organic loading
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3837

Search results for: organic loading

537 Development of Micelle-Mediated Sr(II) Fluorescent Analysis System

Authors: K. Akutsu, S. Mori, T. Hanashima

Abstract:

Fluorescent probes are useful for the selective detection of trace amount of ions and biomolecular imaging in living cells. Various kinds of metal ion-selective fluorescent compounds have been developed, and some compounds have been applied as effective metal ion-selective fluorescent probes. However, because competition between the ligand and water molecules for the metal ion constitutes a major contribution to the stability of a complex in aqueous solution, it is difficult to develop a highly sensitive, selective, and stable fluorescent probe in aqueous solution. The micelles, these are formed in the surfactant aqueous solution, provides a unique hydrophobic nano-environment for stabilizing metal-organic complexes in aqueous solution. Therefore, we focused on the unique properties of micelles to develop a new fluorescence analysis system. We have been developed a fluorescence analysis system for Sr(II) by using a Sr(II) fluorescent sensor, N-(2-hydroxy-3-(1H-benzimidazol-2-yl)-phenyl)-1-aza-18-crown-6-ether (BIC), and studied its complexation behavior with Sr(II) in micellar solution. We revealed that the stability constant of Sr(II)-BIC complex was 10 times higher than that in aqueous solution. In addition, its detection limit value was also improved up to 300 times by this system. However, the mechanisms of these phenomena have remained obscure. In this study, we investigated the structure of Sr(II)-BIC complex in aqueous micellar solution by combining use the extended X-ray absorption fine structure (EXAFS) and neutron reflectivity (NR) method to understand the unique properties of the fluorescence analysis system from the view point of structural chemistry. EXAFS and NR experiments were performed on BL-27B at KEK-PF and on BL17 SHARAKU at J-PARC MLF, respectively. The obtained EXAFS spectra and their fitting results indicated that Sr(II) and BIC formed a Sr(18-crown-6-ether)-like complex in aqueous micellar solution. The EXAFS results also indicated that the hydrophilic head group of surfactant molecule was directly coordinated with Sr(II). In addition, the NR results also indicated that Sr(II)-BIC complex would interact with the surface of micelle molecules. Therefore, we concluded that Sr(II), BIC, and surfactant molecule formed a ternary complexes in aqueous micellar solution, and at least, it is clear that the improvement of the stability constant in micellar solution is attributed to the result of the formation of Sr(BIC)(surfactant) complex.

Keywords: micell, fluorescent probe, neutron reflectivity, EXAFS

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536 Self-Assembling Layered Double Hydroxide Nanosheets on β-FeOOH Nanorods for Reducing Fire Hazards of Epoxy Resin

Authors: Wei Wang, Yuan Hu

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Epoxy resins (EP), one of the most important thermosetting polymers, is widely applied in various fields due to its desirable properties, such as excellent electrical insulation, low shrinkage, outstanding mechanical stiffness, satisfactory adhesion and solvent resistance. However, like most of the polymeric materials, EP has the fatal drawbacks including inherent flammability and high yield of toxic smoke, which restricts its application in the fields requiring fire safety. So, it is still a challenge and an interesting subject to develop new flame retardants which can not only remarkably improve the flame retardancy, but also render modified resins low toxic gases generation. In recent work, polymer nanocomposites based on nanohybrids that contain two or more kinds of nanofillers have drawn intensive interest, which can realize performance enhancements. The realization of previous hybrids of carbon nanotubes (CNTs) and molybdenum disulfide provides us a novel route to decorate layered double hydroxide (LDH) nanosheets on the surface of β-FeOOH nanorods; the deposited LDH nanosheets can fill the network and promote the work efficiency of β-FeOOH nanorods. Moreover, the synergistic effects between LDH and β-FeOOH can be anticipated to have potential applications in reducing fire hazards of EP composites for the combination of condense-phase and gas-phase mechanism. As reported, β-FeOOH nanorods can act as a core to prepare hybrid nanostructures combining with other nanoparticles through electrostatic attraction through layer-by-layer assembly technique. In this work, LDH nanosheets wrapped β-FeOOH nanorods (LDH-β-FeOOH) hybrids was synthesized by a facile method, with the purpose of combining the characteristics of one dimension (1D) and two dimension (2D), to improve the fire resistance of epoxy resin. The hybrids showed a well dispersion in EP matrix and had no obvious aggregation. Thermogravimetric analysis and cone calorimeter tests confirmed that LDH-β-FeOOH hybrids into EP matrix with a loading of 3% could obviously improve the fire safety of EP composites. The plausible flame retardancy mechanism was explored by thermogravimetric infrared (TG-IR) and X-ray photoelectron spectroscopy. The reasons were concluded: condense-phase and gas-phase. Nanofillers were transferred to the surface of matrix during combustion, which could not only shield EP matrix from external radiation and heat feedback from the fire zone, but also efficiently retard transport of oxygen and flammable pyrolysis.

Keywords: fire hazards, toxic gases, self-assembly, epoxy

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535 Toxicological and Histopathological Studies on the Effect of Tartrazine in Male Albino Rats

Authors: F. Alaa Ali, S. A. Sherein Abdelgayed, S. Osama. EL-Tawil, M. Adel Bakeer

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Tartrazine is an organic azo dyes food additive widely used in foods, drugs, and cosmetics. The present study aimed to investigate the toxic effects of tartrazine on kidneys and liver biomarkers in addition to the investigation of oxidative stress and change of histopathological structure of liver and kidneys in 30 male rats. Tartrazine was orally administrated daily at dose 200 mg/ kg bw (1/ 10 LD50) for sixty days. Serum and tissue samples were collected at the end of the experiment to investigate the underlying mechanism of tartrazine through assessment oxidative stress (Glutathione (GSH), Superoxide dismutase (SOD) and malondialdehyde (MDA) and biochemical markers (alanine aminotransferase (ALT), aspartate aminotransferase (AST), Total protein and Urea). Liver and kidneys tissue were collected and preserved in 10% formalin for histopathological examination. The obtained values were statistically analyzed by one way analysis of variance (ANOVA) followed by multiple comparison test. Biochemical analysis revealed that tartrazine induced significant increase in serum ALT, AST, total protein, urea level compared to control group. Tartrazine showed significant decrease in liver GSH and SOD where their values when compared to control group. Tartrazine induced increase in liver MDA compared to control group. Histopathology of the liver showed diffuse vacuolar degeneration in hepatic parenchyma, the portal area showed sever changes sever in hepatoportal blood vessels and in the bile ducts. The kidneys showed degenerated tubules at the cortex together with mononuclear leucocytes inflammatory cells infiltration. There is perivascular edema with inflammatory cell infiltration surrounding the congested and hyalinized vascular wall of blood vessel. The present study indicates that the subchronic effects of tartrazine have a toxic effect on the liver and kidneys together with induction of oxidative stress by formation of free radicals. Therefore, people should avoid the hazards of consuming tartrazine.

Keywords: albino rats, tartrazine, toxicity, pathology

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534 Study on Accumulation of Heavy Metals in Sweet Potato, Grown in Industrially Polluted Regions

Authors: Violina Angelova, Galina Pevicharova

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A comparative research had been carried out to allow us to determine the quantities and the centers of accumulation of Pb, Cu, Zn and Cd in the vegetative and reproductive organs of the sweet potatoes and to ascertain the possibilities for growing them on soils, polluted with heavy metals. The experiments were performed on agricultural fields contaminated by the (1) Non-Ferrous-Metal Works near Plovdiv, (2) Lead and Zinc Complex near Kardjali and (3) a copper smelter near Pirdop, Bulgaria. The soils used in this experiment were characterized by acid, neutral and slightly alkaline reaction, loamy texture and a moderate content of organic matter. The total content of Zn, Pb, and Cd was high and exceeded the limit value in agriculture soils. Sweet potatoes were in a 2-year rotation scheme on three blocks in the experimental field. On reaching commercial ripeness the sweet potatoes were gathered and the contents of heavy metals in their different parts – root, tuber (peel and core), leaves and stems, were determined after microwave mineralization. The quantitative measurements were carried out with inductively coupled plasma atomic emission spectroscopy. The contamination of the sweet potatoes was due mainly to the presence of heavy metals in the soil, which entered the plants through their root system, as well as by diffusion through the peel. Pb, Cu, Zn, and Cd were selectively accumulated in the underground parts of the sweet potatoes, and most of all in the root system and the peel. Heavy metals have an impact on the development and productivity of the sweet potatoes. The high anthropogenic contamination leads to an increased assimilation of heavy metals which reduces the yield and the quality of the production of sweet potatoes, as well as leads to decrease of the absolute dry substance and the quantity of sugars in sweet potatoes. Sweet potatoes could be grown on soils, which are light to medium polluted with lead, zinc, and cadmium, as they do not accumulate these elements. On heavily polluted soils, however, (Pb – 1504 mg/kg, Zn – 3322 mg/kg, Cd – 47 mg/kg) the growing of sweet potatoes is not allowed, as the accumulation of Pb and Cd in the core of the potatoes exceeds the Maximum Acceptable Concentration. Acknowledgment: The authors gratefully acknowledge the financial support by the Bulgarian National Science Fund (Project DFNI DH04/9).

Keywords: heavy metals, polluted soils, sweet potatoes, uptake

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533 Effluent from Royal LERD Wastewater Treatment Systems to Furnish Nutrients for Phytoplankton to Generate the Abundance of Hard Clam (Meretrix spp.) on Muddy Beach

Authors: O. Phewnil, S. Khowhit, W. Inkapatanakul, A. Boutson, K. Chunkao, O. Chueawong, T. Pattamapitoon, N. Chanwong, C. Nimpee

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The King’s Royally Initiated Laem Phak Bia Environmental Research and Development Project (“the Royal LERD Project”) is located in Laem Phak Bia Sub-District, Ban Laem District, Phetchaburi Province, Thailand. Phetchaburi municipal wastewater was treated with a simple technology by using aquatic plants, constructed wetland, oxidation ponds through a nature-by-nature process. The effluent from the Royal LERD Project was discharged into Laem Phak Bia muddy beach. The soil sediment samples were collected from two zones (200 and 600 meters from the coast of the beach), and tested for cation-exchange capacity (CEC), pH and organic matter and soil particles content. The marine water samples were also collected from the beach in wet and dry seasons and analyzed for its quality and compositions, including but not limited to, biochemical oxygen demand (BOD), dissolved oxygen (DO), suspended solids (SS), nutrients, heavy metals (As, Cd, Cr, Hg, and Pb), and phytoplankton at high and low tides. The soil texture was sandy loam with high concentration of calcium and magnesium which showed a property of base (pH 8). The marine water was qualified with the standard limits of coastal water quality. A dominant species was Coscinodiscus sp. It was found approximately 70.46% of total phytoplankton species in Meretrix casta gastrointestinal tract. The concentration of the heavy metals (As, Cd, Cr, Hg, Ni and Pb) in the tissues and water content of two species of hard clams indicated that heavy metals in Meretrix casta were higher than those in Meretrix meretrix. However, the heavy metals in both species were under the standard limits and safe for consumption. It can be concluded that nutrients in effluent from the wastewater treatment systems play important role in promoting the growth of phytoplankton and generating abundance of hard clams on muddy beach.

Keywords: wastewater, phytoplankton, hard clam (Meretrix spp.), muddy beach

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532 Peat Soil Stabilization by Using Sugarcane Bagasse Ash (SCBA)

Authors: Mohd. Khaidir Abu Talib, Noriyuki Yasufuku, Ryohei Ishikura

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It is well recognized that peat can impede the proper hydration of cement because of high organic content, presence of humic acid and less solid particles. That means the large amount of cement is required in order to neutralize the acids or otherwise the process of the peat stabilization remains retarded. Nevertheless, adding a great quantity of cement into the peat is absolutely an unfriendly and uneconomical solution. Sugarcane production is world number one commodities and produced a lot of bagasse. Bagasse is burnt to generate power required for diverse activities in the factory and leave bagasse ash as a waste. Increasing concern of disposal of bagasse residual creates interest to explore the potential application of this material. The objective of this study is to develop alternative binders that are environment friendly and contribute towards sustainable management by utilizing sugarcane bagasse ash (SCBA) in the stabilization of peat soil. Alongside SCBA, Ordinary Portland Cement (OPC), calcium chloride (CaCl2) and silica sand (K7) were used as additives to stabilize the peat that sampled from Hokkaido, Japan. In obtaining the optimal mix design, specimens of stabilized peat were tested in unconfined compression. It was found that stabilized peat comprising 20% and 5% (PCB1-20 and PCB2-5) partial replacement of OPC with SCBA 1 and SCBA 2 attain the maximum unconfined compressive strength (UCS) and discovered greater than untreated soil (P) and UCS of peat-cement (PC) specimen. At the optimal mix design, the UCS of the stabilized peat specimens increased with increasing of curing time, preloading during curing, OPC dosage and K7 dosage. For PCB1-20 mixture, inclusion of a minimum OPC dosage of 300 kg/m3 and K7 dosage of 500 kg/m3 along with curing under 20kPa pressure is recommendable for the peat stabilization to be effective. However for PCB2-5 mixture, it suggested to use more OPC and K7 dosage or alternatively increase the preloading during curing to 40kPa in order to achieve minimum strength target. It can be concluded that SCBA 1 has better quality than SCBA 2 in peat stabilization especially the contribution made by its fine particle size.

Keywords: peat stabilization, sugarcane bagasse ash utilization, partial cement replacement, unconfined strength

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531 Materials and Techniques of Anonymous Egyptian Polychrome Cartonnage Mummy Mask: A Multiple Analytical Study

Authors: Hanaa A. Al-Gaoudi, Hassan Ebeid

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The research investigates the materials and processes used in the manufacturing of an Egyptian polychrome cartonnage mummy mask with the aim of dating this object and establishing trade patterns of certain materials that were used and available at the time of ancient Egypt. This anonymous-source object was held in the basement storage of the Egyptian Museum in Cairo (EMC) and has never been on display. Furthermore, there is no information available regarding its owner, provenance, date, and even the time of its possession by the museum. Moreover, the object is in a very poor condition where almost two-thirds of the mask was bent and has never received any previous conservation treatment. This research has utilized well-established multi-analytical methods to identify the considerable diversity of materials that have been used in the manufacturing of this object. These methods include Computed Tomography Scan (CT scan) to acquire detailed pictures of the inside physical structure and condition of the bended layers. Dino-Lite portable digital microscope, scanning electron microscopy with energy dispersive X-ray spectrometer (SEM-EDX), and the non-invasive imaging technique of multispectral imaging (MSI) to obtain information about the physical characteristics and condition of the painted layers and to examine the microstructure of the materials. Portable XRF Spectrometer (PXRF) and X-Ray powder diffraction (XRD) to identify mineral phases and the bulk element composition in the gilded layer, ground, and pigments; Fourier-transform infrared (FTIR) to identify organic compounds and their molecular characterization; accelerator mass spectrometry (AMS 14C) to date the object. Preliminary results suggest that there are no human remains inside the object, and the textile support is linen fibres with tabby weave 1/1 and these fibres are in a very bad condition. Several pigments have been identified, such as Egyptian blue, Magnetite, Egyptian green frit, Hematite, Calcite, and Cinnabar; moreover, the gilded layers are pure gold and the binding media in the pigments is Arabic gum and animal glue in the textile support layer.

Keywords: analytical methods, Egyptian museum, mummy mask, pigments, textile

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530 An Ethno-Scientific Approach for Restoration of South Indian Heritage Rice Varieties

Authors: A. Sathya, C. Manojkumar, D. Visithra

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The South Indian peninsula has rich diversity of both heritage and conventional rice varieties. With the prime focus set on high yield and increased productivity, a number of traditional/heritage rice varieties have dwindled into the forgotten past. At present, in the face of climate change, the hybrids and conventional varieties struggle for sustainable yield. The need of copious irrigation and high nutrient inputs for the hybrids and conventional varieties have cornered the farming and research community to resort to heritage rice varieties for their sturdy survival capability. An ethno-scientific effort has been taken in the Cauvery delta tracts of South India to restore these traditional/heritage rice varieties. A closer field level performance evaluation under organic condition has been undertaken for 10 heritage rice varieties. The morpho-agronomic characterization across vegetative and reproductive stages have revealed a pattern of variation in duration, plant height, number of tillers, productive tillers, etc. The shortest duration was recorded for a variety with the vernacular name of ‘Arubadaam kuruvai’. A traditional rice variety called ‘Maapillai samba’ is claimed to impart instant energy. The supernatant water of the overnight soaked cooked rice of Maapillai samba is a source of instant energy. The physico-chemical analysis of this variety is being explored for its instant nutritional boosting ability. Wide spectrum of nutritional characters including palatability and marketability preferences has also been analyzed for all these 10 heritage rice varieties. A ‘Farmer’s harvest day festival’ was organized, providing opportunity for the ‘Cauvery delta farmers’ to identify the special features and exchange their views on these standing golden ripe paddy varieties directly. The airing of their ethnic knowledge pooled with interesting scientific investigations of these 10 rich heritage rice varieties of South India undertaken will be elaborately discussed enlightening the perspectives on the pathway of resurrection and restoration of this heritage of the past.

Keywords: biodiversity, conservation, heritage, rice, traditional, varieties

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529 Morphological Investigation of Sprawling Along Emerging Peri-Urban Transit Corridor of Mowe-Ibafo Axis of the Lagos Megacity Region

Authors: Folayele Oluyemi Akindeju, Tobi Joseph Ajoro

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The city as a complex system exhibiting chaotic behaviour is in a state of constant change, in response to prevailing social, economic, environmental and technological factors. Without adequate investigation and control mechanisms to tame the sporadic nature of growth in most urban areas of cities in developing regions, organic sprawling visibly manifests with its attendant problems, most especially at peri-urban areas. The Lagos Megacity region in southwest Nigeria, as one of the largest megacities in the world contends with the challenges of sprawling at the peri-urban areas especially along emerging transit corridors. Due to the seemingly unpredictable nature of this growth, this paper attempts a morphological investigation into the growth of peri-urban settlements along the Mowe-Ibafo transit corridor of the Megacity region over a temporal space of three decades (1984-2014). This study adopts the application of the Fractal Analysis and Regression Analysis methods through the correlation of population density and fractal dimension values to establish the pattern and nature of growth, due to the inadequacies of conventional methods of urban analysis which cannot deal with the unpredictability of such complex urban forms as the peri-urban areas. It was deduced that the dynamic urban expansion in the last three decades resulted in about 74.2% urban change rate between 1984 and 2000 and 63.4% urban change rate between 2000 and 2014. With the R2 value between the fractal dimension and population density been 1, the regression model indicates a positive correlation between Fractal Dimension (D) and Population Density (pop/km2), where the increase in the population density from 5740 pop/km2 to 8060 pop/km2 and later decrease to 7580 pop/km2 leads to an increase in the fractal dimension of urban growth from 1.451 in 1984 to 1.853 in 2014. This, therefore, justifies the ability to predict and determine the nature and direction of growth of complex entities and is sufficient to substantially suggest the need for adequate policy framework towards sustainable urban planning and infrastructural provision in the Peri-urban areas.

Keywords: fractal analysis, Lagos Megacity, peri-urban, sprawling, urban morphology

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528 Hierarchical Zeolites as Potential Carriers of Curcumin

Authors: Ewelina Musielak, Agnieszka Feliczak-Guzik, Izabela Nowak

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Based on the latest data, it is expected that the substances of therapeutic interest used will be as natural as possible. Therefore, active substances with the highest possible efficacy and low toxicity are sought. Among natural substances with therapeutic effects, those of plant origin stand out. Curcumin isolated from the Curcuma longa plant has proven to be particularly important from a medical point of view. Due to its ability to regulate many important transcription factors, cytokines, and protein kinases, curcumin has found use as an anti-inflammatory, antioxidant, antiproliferative, antiangiogenic, and anticancer agent. The unfavorable properties of curcumin, such as low solubility, poor bioavailability, and rapid degradation under neutral or alkaline pH conditions, limit its clinical application. These problems can be solved by combining curcumin with suitable carriers such as hierarchical zeolites. This is a new class of materials that exhibit several advantages. Hierarchical zeolites used as drug carriers enable delayed release of the active ingredient and promote drug transport to the desired tissues and organs. In addition, hierarchical zeolites play an important role in regulating micronutrient levels in the body and have been used successfully in cancer diagnosis and therapy. To apply curcumin to hierarchical zeolites synthesized from commercial FAU zeolite, solutions containing curcumin, carrier and acetone were prepared. The prepared mixtures were then stirred on a magnetic stirrer for 24 h at room temperature. The curcumin-filled hierarchical zeolites were drained into a glass funnel, where they were washed three times with acetone and distilled water, after which the obtained material was air-dried until completely dry. In addition, the effect of piperine addition to zeolite carrier containing a sufficient amount of curcumin was studied. The resulting products were weighed and the percentage of pure curcumin in the hierarchical zeolite was calculated. All the synthesized materials were characterized by several techniques: elemental analysis, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, Fourier transform infrared (FT-IR), N2 adsorption, and X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The aim of the presented study was to improve the biological activity of curcumin by applying it to hierarchical zeolites based on FAU zeolite. The results showed that the loading efficiency of curcumin into hierarchical zeolites based on commercial FAU-type zeolite is enhanced by modifying the zeolite carrier itself. The hierarchical zeolites proved to be very good and efficient carriers of plant-derived active ingredients such as curcumin.

Keywords: carriers of active substances, curcumin, hierarchical zeolites, incorporation

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527 Hydrogen Induced Fatigue Crack Growth in Pipeline Steel API 5L X65: A Combined Experimental and Modelling Approach

Authors: H. M. Ferreira, H. Cockings, D. F. Gordon

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Climate change is driving a transition in the energy sector, with low-carbon energy sources such as hydrogen (H2) emerging as an alternative to fossil fuels. However, the successful implementation of a hydrogen economy requires an expansion of hydrogen production, transportation and storage capacity. The costs associated with this transition are high but can be partly mitigated by adapting the current oil and natural gas networks, such as pipeline, an important component of the hydrogen infrastructure, to transport pure or blended hydrogen. Steel pipelines are designed to withstand fatigue, one of the most common causes of pipeline failure. However, it is well established that some materials, such as steel, can fail prematurely in service when exposed to hydrogen-rich environments. Therefore, it is imperative to evaluate how defects (e.g. inclusions, dents, and pre-existing cracks) will interact with hydrogen under cyclic loading and, ultimately, to what extent hydrogen induced failure will limit the service conditions of steel pipelines. This presentation will explore how the exposure of API 5L X65 to a hydrogen-rich environment and cyclic loads will influence its susceptibility to hydrogen induced failure. That evaluation will be performed by a combination of several techniques such as hydrogen permeation testing (ISO 17081:2014), fatigue crack growth (FCG) testing (ISO 12108:2018 and AFGROW modelling), combined with microstructural and fractographic analysis. The development of a FCG test setup coupled with an electrochemical cell will be discussed, along with the advantages and challenges of measuring crack growth rates in electrolytic hydrogen environments. A detailed assessment of several electrolytic charging conditions will also be presented, using hydrogen permeation testing as a method to correlate the different charging settings to equivalent hydrogen concentrations and effective diffusivity coefficients, not only on the base material but also on the heat affected zone and weld of the pipelines. The experimental work is being complemented with AFGROW, a useful FCG modelling software that has helped inform testing parameters and which will also be developed to ultimately help industry experts perform structural integrity analysis and remnant life characterisation of pipeline steels under representative conditions. The results from this research will allow to conclude if there is an acceleration of the crack growth rate of API 5L X65 under the influence of a hydrogen-rich environment, an important aspect that needs to be rectified instandards and codes of practice on pipeline integrity evaluation and maintenance.

Keywords: AFGROW, electrolytic hydrogen charging, fatigue crack growth, hydrogen, pipeline, steel

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526 Ionic Liquids-Polymer Nanoparticle Systems as Breakthrough Tools to Improve the Leprosy Treatment

Authors: A. Julio, R. Caparica, S. Costa Lima, S. Reis, J. G. Costa, P. Fonte, T. Santos De Almeida

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The Mycobacterium leprae causes a chronic and infectious disease called leprosy, which the most common symptoms are peripheral neuropathy and deformation of several parts of the body. The pharmacological treatment of leprosy is a combined therapy with three different drugs, rifampicin, clofazimine, and dapsone. However, clofazimine and dapsone have poor solubility in water and also low bioavailability. Thus, it is crucial to develop strategies to overcome such drawbacks. The use of ionic liquids (ILs) may be a strategy to overcome the low solubility since they have been used as solubility promoters. ILs are salts, liquid below 100 ºC or even at room temperature, that may be placed in water, oils or hydroalcoholic solutions. Another approach may be the encapsulation of drugs into polymeric nanoparticles, which improves their bioavailability. In this study, two different classes of ILs were used, the imidazole- and the choline-based ionic liquids, as solubility enhancers of the poorly soluble antileprotic drugs. Thus, after the solubility studies, it was developed IL-PLGA nanoparticles hybrid systems to deliver such drugs. First of all, the solubility studies of clofazimine and dapsone were performed in water and in water: IL mixtures, at ILs concentrations where cell viability is maintained, at room temperature for 72 hours. For both drugs, it was observed an improvement on the drug solubility and [Cho][Phe] showed to be the best solubility enhancer, especially for clofazimine, where it was observed a 10-fold improvement. Later, it was produced nanoparticles, with a polymeric matrix of poly(lactic-co-glycolic acid) (PLGA) 75:25, by a modified solvent-evaporation W/O/W double emulsion technique in the presence of [Cho][Phe]. Thus, the inner phase was an aqueous solution of 0.2 % (v/v) of the above IL with each drug to its maximum solubility determined on the previous study. After the production, the nanosystem hybrid was physicochemically characterized. The produced nanoparticles had a diameter of around 580 nm and 640 nm, for clofazimine and dapsone, respectively. Regarding the polydispersity index, it was in agreement of the recommended value of this parameter for drug delivery systems (around 0.3). The association efficiency (AE) of the developed hybrid nanosystems demonstrated promising AE values for both drugs, given their low solubility (64.0 ± 4.0 % for clofazimine and 58.6 ± 10.0 % for dapsone), that prospects the capacity of these delivery systems to enhance the bioavailability and loading of clofazimine and dapsone. Overall, the study achievement may signify an upgrading of the patient’s quality of life, since it may mean a change in the therapeutic scheme, not requiring doses of drug so high to obtain a therapeutic effect. The authors would like to thank Fundação para a Ciência e a Tecnologia, Portugal (FCT/MCTES (PIDDAC), UID/DTP/04567/2016-CBIOS/PRUID/BI2/2018).

Keywords: ionic liquids, ionic liquids-PLGA nanoparticles hybrid systems, leprosy treatment, solubility

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525 Vapour Liquid Equilibrium Measurement of CO₂ Absorption in Aqueous 2-Aminoethylpiperazine (AEP)

Authors: Anirban Dey, Sukanta Kumar Dash, Bishnupada Mandal

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Carbondioxide (CO2) is a major greenhouse gas responsible for global warming and fossil fuel power plants are the main emitting sources. Therefore the capture of CO2 is essential to maintain the emission levels according to the standards. Carbon capture and storage (CCS) is considered as an important option for stabilization of atmospheric greenhouse gases and minimizing global warming effects. There are three approaches towards CCS: Pre combustion capture where carbon is removed from the fuel prior to combustion, Oxy-fuel combustion, where coal is combusted with oxygen instead of air and Post combustion capture where the fossil fuel is combusted to produce energy and CO2 is removed from the flue gases left after the combustion process. Post combustion technology offers some advantage as existing combustion technologies can still be used without adopting major changes on them. A number of separation processes could be utilized part of post –combustion capture technology. These include (a) Physical absorption (b) Chemical absorption (c) Membrane separation (d) Adsorption. Chemical absorption is one of the most extensively used technologies for large scale CO2 capture systems. The industrially important solvents used are primary amines like Monoethanolamine (MEA) and Diglycolamine (DGA), secondary amines like diethanolamine (DEA) and Diisopropanolamine (DIPA) and tertiary amines like methyldiethanolamine (MDEA) and Triethanolamine (TEA). Primary and secondary amines react fast and directly with CO2 to form stable carbamates while Tertiary amines do not react directly with CO2 as in aqueous solution they catalyzes the hydrolysis of CO2 to form a bicarbonate ion and a protonated amine. Concentrated Piperazine (PZ) has been proposed as a better solvent as well as activator for CO2 capture from flue gas with a 10 % energy benefit compared to conventional amines such as MEA. However, the application of concentrated PZ is limited due to its low solubility in water at low temperature and lean CO2 loading. So following the performance of PZ its derivative 2-Aminoethyl piperazine (AEP) which is a cyclic amine can be explored as an activator towards the absorption of CO2. Vapour liquid equilibrium (VLE) in CO2 capture systems is an important factor for the design of separation equipment and gas treating processes. For proper thermodynamic modeling accurate equilibrium data for the solvent system over a wide range of temperatures, pressure and composition is essential. The present work focuses on the determination of VLE data for (AEP + H2O) system at 40 °C for various composition range.

Keywords: absorption, aminoethyl piperazine, carbondioxide, vapour liquid equilibrium

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524 Carbon Nanotube Field Effect Transistor - a Review

Authors: P. Geetha, R. S. D. Wahida Banu

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The crowning advances in Silicon based electronic technology have dominated the computation world for the past decades. The captivating performance of Si devices lies in sustainable scaling down of the physical dimensions, by that increasing device density and improved performance. But, the fundamental limitations due to physical, technological, economical, and manufacture features restrict further miniaturization of Si based devices. The pit falls are due to scaling down of the devices such as process variation, short channel effects, high leakage currents, and reliability concerns. To fix the above-said problems, it is needed either to follow a new concept that will manage the current hitches or to support the available concept with different materials. The new concept is to design spintronics, quantum computation or two terminal molecular devices. Otherwise, presently used well known three terminal devices can be modified with different materials that suits to address the scaling down difficulties. The first approach will occupy in the far future since it needs considerable effort; the second path is a bright light towards the travel. Modelling paves way to know not only the current-voltage characteristics but also the performance of new devices. So, it is desirable to model a new device of suitable gate control and project the its abilities towards capability of handling high current, high power, high frequency, short delay, and high velocity with excellent electronic and optical properties. Carbon nanotube became a thriving material to replace silicon in nano devices. A well-planned optimized utilization of the carbon material leads to many more advantages. The unique nature of this organic material allows the recent developments in almost all fields of applications from an automobile industry to medical science, especially in electronics field-on which the automation industry depends. More research works were being done in this area. This paper reviews the carbon nanotube field effect transistor with various gate configurations, number of channel element, CNT wall configurations and different modelling techniques.

Keywords: array of channels, carbon nanotube field effect transistor, double gate transistor, gate wrap around transistor, modelling, multi-walled CNT, single-walled CNT

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523 Utilization and Proximate Composition of Nile Tilapia, Common Carp and African Mudfish Polycultured in Fertilized Ponds

Authors: I. A. Yola

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Impact of poultry dropping, cow dung and rumen content on utilization and proximate composition of Oreochromis niliticus, Clarias gariepinus and Cyprinus capio in a polyculture system were studied. The research was conducted over a period of 52 weeks. Poultry droppings (PD), cow dung (CD) and rumen content (RC) were applied at three levels 30g,60g and 120g/m2/week, 25g,50g and 100g/m2/week and 22g, 44g and 88g/m2/week treatment, respectively. The control only conventional feed with 40% CP without manure application was used. Physicochemical and biological properties measured were higher in manure pond than control. The difference was statistically significant (P < 0.05) between and within treatments with exception of temperature with a combined mean of 27.900C. The water was consistently alkaline with mean values for pH of 6.61, transparency 22.6cm, conductivity 35.00µhos/cm, dissolved oxygen 4.6 mg/l, biological oxygen demand 2.8mg/l, nitrate and phosphates 0.9mg/l and 0.35mg/l, respectively. The three fish species increase in weight with increased manure rate, with a higher value in PD treatment on C. capio record 340g, O. niloticus weighed 310g and C. gariepinus 280g over the experimental period. Fishes fed supplementary diet (control) grew bigger with highest value on C. capio (685g) O. niloticus (620g) and then C. gariepinus (526g). The differences were statistically significant (P < 0.05). The result of whole body proximate analysis indicated that various manures and rates had an irregular pattern on the protein and ash gain per 100g of fish body weight gain. The combined means for whole fish carcass protein, lipids, moisture, ash and gross energy were 11.84, 2.43, 74.63, 3.00 and 109.9 respectively. The notable exceptions were significant (p < 0.05) increases in body fat and gross energy gains in all fish species accompanied by decreases in percentages of moisture as manure rates increased. Survival percentage decreases from 80% to 70%. It is recommended to use poultry dropping as manure/feeds at the rate of 120kg/ha/week for good performances in polyculture.

Keywords: organic manure, Nile tilapia, African mud fish, common carp, proximate composition

Procedia PDF Downloads 523
522 Stress Corrosion Crackings Test of Candidate Materials in Support of the Development of the European Small Modular Supercritical Water Cooled Rector Concept

Authors: Radek Novotny, Michal Novak, Daniela Marusakova, Monika Sipova, Hugo Fuentes, Peter Borst

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This research has been conducted within the European HORIZON 2020 project ECC-SMART. The main objective is to assess whether it is feasible to design and develop a small modular reactor (SMR) that would be cooled by supercritical water (SCW). One of the main objectives for material research concerns the corrosion of the candidate cladding materials. The experimental part has been conducted in support of the qualification procedure of the future SCW-SMR constructional materials. The last objective was to identify the gaps in current norms and guidelines. Apart from corrosion, resistance testing of candidate materials stresses corrosion cracking susceptibility tests have been performed in supercritical water. This paper describes part of these tests, in particular, those slow strain rate tensile loading applied for tangential ring shape specimens of two candidate materials, Alloy 800H and 310S stainless steel. These ring tensile tests are one the methods used for tensile testing of nuclear cladding. Here full circular heads with dimensions roughly equal to the inner diameter of the sample and the gage sections are placed in the parallel direction to the applied load. Slow strain rate tensile tests have been conducted in 380 or 500oC supercritical water applying two different elongation rates, 1x10-6 and 1x10-7 s-1. The effect of temperature and dissolved oxygen content on the SCC susceptibility of Alloy 800H and 310S stainless steel was investigated when two different temperatures and concentrations of dissolved oxygen were applied in supercritical water. The post-fracture analysis includes fractographic analysis of the fracture surfaces using SEM as well as cross-sectional analysis on the occurrence of secondary cracks. Assessment of the effect of environment and dissolved oxygen content was by comparing to the results of the reference tests performed in air and N2 gas overpressure. The effect of high temperature on creep and its role in the initiation of SCC was assessed as well. It has been concluded that the applied test method could be very useful for the investigation of stress corrosion cracking susceptibility of candidate cladding materials in supercritical water.

Keywords: stress corrosion cracking, ring tensile tests, super-critical water, alloy 800H, 310S stainless steel

Procedia PDF Downloads 61
521 Green Synthesis of Nanosilver-Loaded Hydrogel Nanocomposites for Antibacterial Application

Authors: D. Berdous, H. Ferfera-Harrar

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Superabsorbent polymers (SAPs) or hydrogels with three-dimensional hydrophilic network structure are high-performance water absorbent and retention materials. The in situ synthesis of metal nanoparticles within polymeric network as antibacterial agents for bio-applications is an approach that takes advantage of the existing free-space into networks, which not only acts as a template for nucleation of nanoparticles, but also provides long term stability and reduces their toxicity by delaying their oxidation and release. In this work, SAP/nanosilver nanocomposites were successfully developed by a unique green process at room temperature, which involves in situ formation of silver nanoparticles (AgNPs) within hydrogels as a template. The aim of this study is to investigate whether these AgNPs-loaded hydrogels are potential candidates for antimicrobial applications. Firstly, the superabsorbents were prepared through radical copolymerization via grafting and crosslinking of acrylamide (AAm) onto chitosan backbone (Cs) using potassium persulfate as initiator and N,N’-methylenebisacrylamide as the crosslinker. Then, they were hydrolyzed to achieve superabsorbents with ampholytic properties and uppermost swelling capacity. Lastly, the AgNPs were biosynthesized and entrapped into hydrogels through a simple, eco-friendly and cost-effective method using aqueous silver nitrate as a silver precursor and curcuma longa tuber-powder extracts as both reducing and stabilizing agent. The formed superabsorbents nanocomposites (Cs-g-PAAm)/AgNPs were characterized by X-ray Diffraction (XRD), UV-visible Spectroscopy, Attenuated Total reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR), Inductively Coupled Plasma (ICP), and Thermogravimetric Analysis (TGA). Microscopic surface structure analyzed by Transmission Electron Microscopy (TEM) has showed spherical shapes of AgNPs with size in the range of 3-15 nm. The extent of nanosilver loading was decreased by increasing Cs content into network. The silver-loaded hydrogel was thermally more stable than the unloaded dry hydrogel counterpart. The swelling equilibrium degree (Q) and centrifuge retention capacity (CRC) in deionized water were affected by both contents of Cs and the entrapped AgNPs. The nanosilver-embedded hydrogels exhibited antibacterial activity against Escherichia coli and Staphylococcus aureus bacteria. These comprehensive results suggest that the elaborated AgNPs-loaded nanomaterials could be used to produce valuable wound dressing.

Keywords: antibacterial activity, nanocomposites, silver nanoparticles, superabsorbent Hydrogel

Procedia PDF Downloads 218
520 Characterization of Aerosol Particles in Ilorin, Nigeria: Ground-Based Measurement Approach

Authors: Razaq A. Olaitan, Ayansina Ayanlade

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Understanding aerosol properties is the main goal of global research in order to lower the uncertainty associated with climate change in the trends and magnitude of aerosol particles. In order to identify aerosol particle types, optical properties, and the relationship between aerosol properties and particle concentration between 2019 and 2021, a study conducted in Ilorin, Nigeria, examined the aerosol robotic network's ground-based sun/sky scanning radiometer. The AERONET algorithm version 2 was utilized to retrieve monthly data on aerosol optical depth and angstrom exponent. The version 3 algorithm, which is an almucantar level 2 inversion, was employed to retrieve daily data on single scattering albedo and aerosol size distribution. Excel 2016 was used to analyze the data's monthly, seasonal, and annual mean averages. The distribution of different types of aerosols was analyzed using scatterplots, and the optical properties of the aerosol were investigated using pertinent mathematical theorems. To comprehend the relationships between particle concentration and properties, correlation statistics were employed. Based on the premise that aerosol characteristics must remain constant in both magnitude and trend across time and space, the study's findings indicate that the types of aerosols identified between 2019 and 2021 are as follows: 29.22% urban industrial (UI) aerosol type, 37.08% desert (D) aerosol type, 10.67% biomass burning (BB), and 23.03% urban mix (Um) aerosol type. Convective wind systems, which frequently carry particles as they blow over long distances in the atmosphere, have been responsible for the peak-of-the-columnar aerosol loadings, which were observed during August of the study period. The study has shown that while coarse mode particles dominate, fine particles are increasing in seasonal and annual trends. Burning biomass and human activities in the city are linked to these trends. The study found that the majority of particles are highly absorbing black carbon, with the fine mode having a volume median radius of 0.08 to 0.12 meters. The investigation also revealed that there is a positive coefficient of correlation (r = 0.57) between changes in aerosol particle concentration and changes in aerosol properties. Human activity is rapidly increasing in Ilorin, causing changes in aerosol properties, indicating potential health risks from climate change and human influence on geological and environmental systems.

Keywords: aerosol loading, aerosol types, health risks, optical properties

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519 Co-Participation: Towards the Sustainable Micro-Rural Complex in China

Authors: Danhua Xu, Zhenlan Qian, Zhu Wang, Jiayan Fu, Ling Wang

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A new business mode called rural complex is proposed by the China’s government to promote the development the economy in the rural area. However, for the sake of current national conditions including the great number of labor farmers owning the small scale farmlands and the uncertain enthusiasm from the enterprises, it is challenging to develop the big scale rural complex. To react to the dilemmas, this paper puts forward the micro-rural complex to boost the small scale farms by co-participation from a bottom-up mode. By analyzing the potential opportunities to find the suitable mode, exploring the interdisciplinary and interdepartmental co-participation way beyond architecture design and spatial planning between different actors, the paper tries to find a complete process towards the sustainable micro-rural complex and conducts an ongoing practice to optimize it, to bring new insights and reference to the rural development. According to the transformation of the economy, the micro-rural complex will develop into two phases, both of which can be discussed in three parts, the economic mode, the spatial support, and the Cooperating mechanism. The first stage is the agriculture co-participation based on the rise of Community supported agriculture (CSA) in which the consumers buy the products planted in an organic way from the farmers directly with a higher price to support the small-scale agriculture and overcome the food safety issues. The following stage sets up the agritourism catering the citizens with the restaurants, inns and other tourist service facilities to be planned and designed. In the whole process, the interdisciplinary co-participation will play an important role to provide the guidelines and consultation from the agronomists, architects and rural planners to the farmers. This mode has been applied to an on-going farm project, from which to explore the mode in a more practical way. In conclusion, the micro-rural complex aims at creating a balanced urban-rural relationship by co-participation taking advantage of the different actors. The spatial development is considered from the economic mode and social organization. The integration of the mode based on the small-scale agriculture will contribute to a sustainable growth and realize the long run development in the rural area.

Keywords: micro-rural complex, co-participation, sustainable development, China

Procedia PDF Downloads 242
518 Modified Fuzzy Delphi Method to Incorporate Healthcare Stakeholders’ Perspectives in Selecting Quality Improvement Projects’ Criteria

Authors: Alia Aldarmaki, Ahmad Elshennawy

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There is a global shift in healthcare systems’ emphasizing engaging different stakeholders in selecting quality improvement initiatives and incorporating their preferences to improve the healthcare efficiency and outcomes. Although experts bring scientific knowledge based on the scientific model and their personal experience, other stakeholders can bring new insights and information into the decision-making process. This study attempts to explore the impact of incorporating different stakeholders’ preference in identifying the most significant criteria that should be considered in healthcare for electing the improvement projects. A Framework based on a modified Fuzzy Delphi Method (FDM) was built. In addition to, the subject matter experts, doctors/physicians, nurses, administrators, and managers groups contribute to the selection process. The research identifies potential criteria for evaluating projects in healthcare, then utilizes FDM to capture expertise knowledge. The first round in FDM is intended to validate the identified list of criteria from experts; which includes collecting additional criteria from experts that the literature might have overlooked. When an acceptable level of consensus has been reached, a second round is conducted to obtain experts’ and other related stakeholders’ opinions on the appropriate weight of each criterion’s importance using linguistic variables. FDM analyses eliminate or retain the criteria to produce a final list of the critical criteria to select improvement projects in healthcare. Finally, reliability and validity were investigated using Cronbach’s alpha and factor analysis, respectively. Two case studies were carried out in a public hospital in the United Arab Emirates to test the framework. Both cases demonstrate that even though there were common criteria between the experts and the stakeholders, still stakeholders’ perceptions bring additional critical criteria into the evaluation process, which can impact the outcomes. Experts selected criteria related to strategical and managerial aspects, while the other participants preferred criteria related to social aspects such as health and safety and patients’ satisfaction. The health and safety criterion had the highest important weight in both cases. The analysis showed that Cronbach’s alpha value is 0.977 and all criteria have factor loading greater than 0.3. In conclusion, the inclusion of stakeholders’ perspectives is intended to enhance stakeholders’ engagement, improve transparency throughout the decision process, and take robust decisions.

Keywords: Fuzzy Delphi Method, fuzzy number, healthcare, stakeholders

Procedia PDF Downloads 98
517 Microbial Inoculants to Increase the Biomass and Nutrient Uptake of Tithonia Cultivated as Hedgerow Plants to Control Erosion in Ultisols

Authors: Nurhajati Hakim, Kiki Amalia, A. Agustian, H. Hermansah, Y. Yulnafatmawita

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Ultisols require greater amounts of fertilizer application compared to other soils and susceptible to erosion. Unfortunately, the price of synthetic fertilizers has increased over time during the years, making them unaffordable for most Indonesian farmers. While terrace technique to control erosion very costly.Over the last century, efforts to reduce reliance on synthetic agro-chemicals fertilizers and erosion control have recently focused on Tithonia diversifolia as a fertilizer alternative, and as hedgerow plant to control erosion. Generally known by its common name of tree marigold or Mexican sunflower, this plant has attracted considerable attention for its prolific production of green biomass, rich in nitrogen, phosphorous and potassium (NPK). In pot experiments has founded some microbial such as Mycorrhizal, Azotobacter, Azospirillum, phosphate solubilizing bacterial (PSB) and fungi (PSF) are expected to play an important role in biomass production and high nutrient uptake of this plant. This issue of importance was pursued further in the following investigation in field condition. The aim of this study was to determine the type of microbial combination suitable for Tithonia cultivation as hedgerow plants in Ultisols which have higher biomass production and nutrient content, and decline soil erosion. The field experiment was conducted with 6 treatments in a randomized block design (RBD) using 3 replications. The treatments were: Tithonia rhizosphere without microbial inoculated (A); Inokulanted by Mycorrhizal + Azotobacter + Azospirillium (B); Mycorrhizal + PSF (C); Mycorrhizal + PSB(D); Mycorrhizal + PSB + PSF(E);and without hedgerow Tithonia (F).The microbial substrates were inoculated into the Tithonia rhizosphere in the nursery. The young Tithonia plants were then planted as hedgerow on Ultisols in the experimental field for 8 months, and pruned once every 2 months. Soil erosion were collected every rainy time. The differences between treatments were statistically significant by HSD test at the 95% level of probability. The result showed that treatment C (mycorrhizal + PSB) was the most effective, and followed by treatment D (mycorrhizal + PSF) in producing higher Tithonia biomass about 8 t dry matter 2000 m-2 ha-1 y-1 and declined soil erosion 71-75%.

Keywords: hedgerow tithonia, microbial inoculants, organic fertilizer, soil erosion control

Procedia PDF Downloads 331
516 Implication of Fractal Kinetics and Diffusion Limited Reaction on Biomass Hydrolysis

Authors: Sibashish Baksi, Ujjaini Sarkar, Sudeshna Saha

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In the present study, hydrolysis of Pinus roxburghi wood powder was carried out with Viscozyme, and kinetics of the hydrolysis has been investigated. Finely ground sawdust is submerged into 2% aqueous peroxide solution (pH=11.5) and pretreated through autoclaving, probe sonication, and alkaline peroxide pretreatment. Afterward, the pretreated material is subjected to hydrolysis. A chain of experiments was executed with delignified biomass (50 g/l) and varying enzyme concentrations (24.2–60.5 g/l). In the present study, 14.32 g/l of glucose, along with 7.35 g/l of xylose, have been recovered with a viscozyme concentration of 48.8 g/l and the same condition was treated as optimum condition. Additionally, thermal deactivation of viscozyme has been investigated and found to be gradually decreasing with escalated enzyme loading from 48.4 g/l (dissociation constant= 0.05 h⁻¹) to 60.5 g/l (dissociation constant= 0.02 h⁻¹). The hydrolysis reaction is a pseudo first-order reaction, and therefore, the rate of the hydrolysis can be expressed as a fractal-like kinetic equation that communicates between the product concentration and hydrolytic time t. It is seen that the value of rate constant (K) increases from 0.008 to 0.017 with augmented enzyme concentration from 24.2 g/l to 60.5 g/l. Greater value of K is associated with stronger enzyme binding capacity of the substrate mass. However, escalated concentration of supplied enzyme ensures improved interaction with more substrate molecules resulting in an enhanced de-polymerization of the polymeric sugar chains per unit time which eventually modifies the physiochemical structure of biomass. All fractal dimensions are in between 0 and 1. Lower the value of fractal dimension, more easily the biomass get hydrolyzed. It can be seen that with increased enzyme concentration from 24.2 g/l to 48.4 g/l, the values of fractal dimension go down from 0.1 to 0.044. This indicates that the presence of more enzyme molecules can more easily hydrolyze the substrate. However, an increased value has been observed with a further increment of enzyme concentration to 60.5g/l because of diffusional limitation. It is evident that the hydrolysis reaction system is a heterogeneous organization, and the product formation rate depends strongly on the enzyme diffusion resistances caused by the rate-limiting structures of the substrate-enzyme complex. Value of the rate constant increases from 1.061 to 2.610 with escalated enzyme concentration from 24.2 to 48.4 g/l. As the rate constant is proportional to Fick’s diffusion coefficient, it can be assumed that with a higher concentration of enzyme, a larger amount of enzyme mass dM diffuses into the substrate through the surface dF per unit time dt. Therefore, a higher rate constant value is associated with a faster diffusion of enzyme into the substrate. Regression analysis of time curves with various enzyme concentrations shows that diffusion resistant constant increases from 0.3 to 0.51 for the first two enzyme concentrations and again decreases with enzyme concentration of 60.5 g/l. During diffusion in a differential scale, the enzyme also experiences a greater resistance during diffusion of larger dM through dF in dt.

Keywords: viscozyme, glucose, fractal kinetics, thermal deactivation

Procedia PDF Downloads 88
515 Characterization of a Broad Range Antimicrobial Substance from Pseudozyma aphidis

Authors: Raviv Harris, Maggie Levy

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Natural product-based pesticides may serve as an alternative to the traditional synthetic pesticides, which have a potentially damaging effect, both to human health and for the environment. Along with plants, microorganisms are a prospective source of such biological pesticides. A unique and active strain of P. aphidis (designated isolate L12, Israel 2004), an epiphytic and non-pathogenic basidiomycete yeast, was isolated in our lab from strawberry leaves. P. aphidis L12 secretions were found to inhibit broad range of plant pathogens. This work demonstrates that metabolites isolated from the biocontrol agent P. aphidis (isolate L12) can inhibit varied fungal and bacterial phytopathogens. Biologically active metabolites were extracted from P. aphidis biomass, using the organic solvent ethyl acetate. The antimicrobial activity of the extract was demonstrated, both in vitro and in planta. Using disk diffusion assays, the following inhibition zones were obtained: 43cm² for Pseudomonas syringae pv. tomato, 28.5cm² for Xanthomonas campestris pv. vesicatoria, 59cm² for Clavibacter michiganensis subsp. michiganensis, 34cm² for Erwinia amylovora and 34cm² for Agrobacterium tumefaciens. Additionally, strong inhibitory activity of the extract against fungi mycelial growth was established, with IC₅₀ values of 606µg ml⁻¹ for Botrytis cinerea, 221µg ml⁻¹ for Pythium spp., 519µg ml⁻¹ for Rhizoctonia solani, 455µg ml⁻¹ for Sclerotinia sclerotiorum, 2270µg ml⁻¹ for Fusarium oxysporum f. sp. lycopersici, and 2038µg ml⁻¹ for Alternaria alternata. The results of the in planta experiments demonstrated a dose-dependent reduction in disease infection. Significant inhibition of B. cinerea lesions on tomato plants was obtained when a spore suspension of this pathogen was treated with extract concentrations higher than 4.2mg ml⁻¹. Concentration of 7mg ml⁻¹ caused a reduction of over 95% in the lesion size of B. cinerea on tomato plants. The strong antimicrobial activity demonstrated both in vitro and in planta against varied phytopathogens, may indicate that the extracted antimicrobial metabolites have potential to serve as natural pesticides in the field.

Keywords: antimicrobial, B. cinerea, metabolites, natural pesticides, P. aphidis

Procedia PDF Downloads 210
514 Extraction, Isolation and Comparative Phtochemical Study of Aegle Marmelos, Calendula Officinalis and Fenugreek

Authors: Nitin Rajan, Kashif Shakeel, Shashank Tiwari, Shachan Sagar

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Background: - Aegle Marmelos (Bael) leaf extract is taken twice daily to treat ophthalmia, ulcers, and intestinal worms, among other ailments. Poultice made from bael leaf is used in the treatment of eye conditions. The leaf juice has a variety of therapeutic applications, with the most notable being the treatment of diabetes. Fenugreek is used to cure red spots around the eyes, as well as to soften the throat and chest and to give relief from coughing. The use of this plant in the form of infusion, powder, pomade, and decoction has been extremely popular in Iranian traditional medicine. The plant may be used to wash one's vaginal linings. This plant is used as an emollient in the lack of appetite, treatment of pellagra, and gastrointestinal problems, as well as a general tonic. Calendula officinalis leaves are used to treat varicose veins on the outside of the body by infusing them. In Europe, the leaves are diaphoretic and resolvent in nature, while the blooms are employed as an emmenagogue and antispasmodic stimulant in Canada and the United States. The flowers were decocted and served as a posset drink when smallpox and measles were common in England, and the fresh juice was used to treat jaundice. Objective: - This study is done to compare the physicochemical parameter of the alcoholic extract of the leaves of Aegle Marmelos, Calendula Officinalis, and Fenugreek. Materials and Methods: Extraction and Isolation of Aegle Marmelos, Calendula Officinalis, Fenugreek, were done. Preliminary phytochemical study for alkaloids, cardiac glycosides, flavonoids, glycosides, phenols, resins, saponins, steroids, tannins, terpenoids of the extract was done individual by using the standard procedure. Result: - The phytochemical screening of Aegle Marmelos, Calendula Officinalis, and Fenugreek shows the presence of alkaloids, carbohydrates, total phenolics, total flavonoids, tannins, saponins gum. Conclusion: - In this study, we have found that crude aqueous and organic solvent extracts of Aegle Marmelos, Calendula Officinalis, and Fenugreek leaves contain some important bioactive compounds and it justifies their use in the traditional medicines for the treatment of different diseases.

Keywords: Aegle Marmelos, Calendula Officinalis, Fenugreek, physiochemical parameter

Procedia PDF Downloads 124
513 Parametrical Analysis of Stain Removal Performance of a Washing Machine: A Case Study of Sebum

Authors: Ozcan B., Koca B., Tuzcuoglu E., Cavusoglu S., Efe A., Bayraktar S.

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A washing machine is mainly used for removing any types of dirt and stains and also eliminating malodorous substances from textile surfaces. Stains originate from various sources from the human body to environmental contamination. Therefore, there are various methods for removing them. They are roughly classified into four different groups: oily (greasy) stains, particulate stains, enzymatic stains and bleachable (oxidizable) stains. Oily stains on clothes surfaces are a common result of being in contact with organic substances of the human body (e.g. perspiration, skin shedding and sebum) or by being exposed to an oily environmental pollutant (e.g. oily foods). Studies showed that human sebum is major component of oily soil found on the garments, and if it is aged under the several environmental conditions, it can generate obstacle yellow stains on the textile surface. In this study, a parametric study was carried out to investigate the key factors affecting the cleaning performance (specifically sebum removal performance) of a washing machine. These parameters are mechanical agitation percentage of tumble, consumed water and total washing period. A full factorial design of the experiment is used to capture all the possible parametric interactions using Minitab 2021 statistical program. Tests are carried out with commercial liquid detergent and 2 different types of sebum-soiled cotton and cotton + polyester fabrics. Parametric results revealed that for both test samples, increasing the washing time and the mechanical agitation could lead to a much better removal result of sebum. However, for each sample, the water amount had different outcomes. Increasing the water amount decreases the performance of cotton + polyester fabrics, while it is favorable for cotton fabric. Besides this, it was also discovered that the type of textile can greatly affect the sebum removal performance. Results showed that cotton + polyester fabrics are much easier to clean compared to cotton fabric

Keywords: laundry, washing machine, low-temperature washing, cold wash, washing efficiency index, sustainability, cleaning performance, stain removal, oily soil, sebum, yellowing

Procedia PDF Downloads 106
512 Fusarium Wilt of Tomato: Plant Growth, Physiology and Biological Disease Management

Authors: Amna Shoaib, Sidrah Hanif, Rashid Mehmood

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Current research work was carried out to check influence of farmyard manure (FYM) in Lycopersicon esculentum L. against Fusarium oxysporum f. sp. lycopersici (FO) in copper polluted soil. Silt-loam soil naturally enriched with 70 ppm of Cu was inoculated with 1 x 106 spore suspensions of FO and incorporated with 0%, 1%, 1.5% or 2% FYM. The multilateral interaction of host-pathogen-metal-organic amendment was assessed in terms of morphology, growth, yield, physiology, biochemistry and metal uptake in tomato plant after 30 and 60 days of sowing. When soil was inoculated with FO, plant growth and biomass were significantly increased during vegetative stage, while declining during flowering stage with substantial increase in productivity over control. Infected plants exhibited late wilting and disease severity was found on 26-50% of plant during reproductive stage. Incorporation of up to 1% FYM suppressed disease severity, improved plant growth and biomass, while it decreased yield. Rest of manure doses was found ineffective in suppressing disease. Content of total chlorophyll, sugar and protein were significantly declined in FO inoculated plants and incorporation of FYM caused significant reduction or no influence on sugar and chlorophyll content, and no pronounced difference among different FYM doses were observed. On the other hand, proline, peroxidase, catalase and nitrate reductase activity were found to be increased in infected plants and incorporation of 1-2% FYM further enhanced the activity of these enzymes. Tomato plant uptake of 30-40% of copper naturally present in the soil and incorporation of 1-2% FYM markedly decreased plant uptake of metal by 15-30%, while increased Cu retention in soil. Present study concludes that lower dose (1%) of FYM could be used to manage disease, increase growth and biomass, while being ineffective for yield and productivity in Cu-polluted soil. Altered physiology/biochemistry of plant in response to any treatment could be served as basis for resistant against pathogen and metal homeostasis in plants.

Keywords: Lycopersicon esculentum, copper, Fusarium wilt, farm yard manure

Procedia PDF Downloads 387
511 Adaptive Strategies to Nutrient Deficiency of Doubled Diploid Citrumelo 4475: A Prospective Study Based on Structural, Ultrastructural, Physiological and Biochemical Parameters

Authors: J. Oustric, L. Berti, J. Santini

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Nowadays, the objective of durable agriculture, and in particular organic agriculture, is to reduce the level of fertilizer inputs used in crops. Limiting the quantity of fertilizer inputs would optimize the economical result and minimizing the environmental impact. Nutrient deficiency, particularly of a major nutrient (N, P, and K), can seriously affect fruit production and quality. In citrus crops, rootstock/scion combinations. In citrus crop, scion/rootstock combinations are used frequently to improve tolerance to various abiotic stresses. New rootstocks are needed to respond to these constraints, and the use of new tetraploid rootstocks better adapted to lower nutrient intake could offer a promising way forward. The aim of this work was to determine whether a better tolerance to nutrient deficiency could be observed in a doubled diploid seedling and whether this tolerance could be observed in common clementine scion if used as rootstocks. We selected diploid (CM2x) and doubled diploid (CM4x) Citrumelo 4475 seedlings and common clementine (C) grafted onto Citrumelo 4475 diploid (C/CM2x) and doubled diploid (C/CM4x) rootstocks. Nutrient deficiency effects on the seedlings and scion/rootstock combinations were analyzed by studying anatomical, structural and ultrastructural determinants (chlorosis, stomata, ostiole and cells and their organelles), photosynthetic properties (leaf net photosynthetic rate (Pₙₑₜ), stomatal conductance (gₛ), chlorophyll a fluorescence (Fᵥ/Fₘ)) and oxidative marker (malondialdehyde). Nutrient deficiency affected differently foliar tissues, physiological parameters, and oxidative metabolism in leaves of seedlings depending on their ploidy level and of common clementine scion depending on their rootstocks ploidy level. Both CM4x and C/CM4x presented lower foliar damages (chlorosis, chloroplasts, mitochondria, and plastoglobuli), photosynthesis processes alteration (Pₙₑₜ, gₛ, and Fᵥ/Fₘ), and malondialdehyde accumulation than CM2x and C/CM2x after nutrient deficiency. Doubled diploid Citrumelo 4475 can improve nutrient deficiency tolerance, and its use as a rootstock allows to confer this tolerance to the common clementine scion.

Keywords: nutrient deficiency, oxidative stress, photosynthesis, polyploid rootstocks

Procedia PDF Downloads 106
510 Enhancing Heavy Oil Recovery: Experimental Insights into Low Salinity Polymer in Sandstone Reservoirs

Authors: Intisar, Khalifa, Salim, Al Busaidi

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Recently, the synergic combination of low salinity water flooding with polymer flooding has been a subject of paramount interest for the oil industry. Numerous studies have investigated the efficiency of enhanced oil recovery using low salinity polymer flooding (LSPF). However, there is no clear conclusion that can explain the incremental oil recovery, determine the main factors controlling the oil recovery process, and define the relative contribution of rock/fluids or fluid/fluid interactions to extra oil recovery. Therefore, this study aims to perform a systematic investigation of the interactions between oil, polymer, low salinity and sandstone rock surface from pore to core scale during LSPF. Partially hydrolyzed polyacrylamide (HPAM) polymer, Boise outcrop, a crude oil sample and reservoir cores from an Omani oil field, and brine at two different salinities were used in the study. Several experimental measurements including static bulk measurements of polymer solutions prepared with brines of high and low salinities, single phase displacement experiments, along with rheological, total organic carbon and ion chromatography measurements to analyze ion exchange reactions, polymer adsorption, and viscosity loss were used. In addition, two-phase experiments were performed to demonstrate the oil recovery efficiency of LSPF. The results revealed that the incremental oil recovery from LSPF was attributed to the combination of the reduction in the water-oil mobility ratio, an increase in the repulsion forces between crude oil/brine/rock interfaces and an increase in pH of the aqueous solution. In addition, lowering the salinity of the make-up brine resulted in a larger conformation (expansion) of the polymer molecules, which in turn resulted in less adsorption and a greater in-situ viscosity without any negative impact on injectivity. This plays a positive role in the oil displacement process. Moreover, the loss of viscosity in the effluent of polymer solutions was lower in low-salinity than in high-salinity brine, indicating that an increase in cations concentration (mainly driven by Ca2+ ions) has stronger effect on the viscosity of high-salinity polymer solution compared with low-salinity polymer.

Keywords: polymer, heavy oil, low salinity, COBR interactions

Procedia PDF Downloads 61
509 Multi-Scale Modeling of Ti-6Al-4V Mechanical Behavior: Size, Dispersion and Crystallographic Texture of Grains Effects

Authors: Fatna Benmessaoud, Mohammed Cheikh, Vencent Velay, Vanessa Vidal, Farhad Rezai-Aria, Christine Boher

Abstract:

Ti-6Al-4V titanium alloy is one of the most widely used materials in aeronautical and aerospace industries. Because of its high specific strength, good fatigue, and corrosion resistance, this alloy is very suitable for moderate temperature applications. At room temperature, Ti-6Al-4V mechanical behavior is generally controlled by the behavior of alpha phase (beta phase percent is less than 8%). The plastic strain of this phase notably based on crystallographic slip can be hindered by various obstacles and mechanisms (crystal lattice friction, sessile dislocations, strengthening by solute atoms and grain boundaries…). The grains aspect of alpha phase (its morphology and texture) and the nature of its crystallographic lattice (which is hexagonal compact) give to plastic strain heterogeneous, discontinuous and anisotropic characteristics at the local scale. The aim of this work is to develop a multi-scale model for Ti-6Al-4V mechanical behavior using crystal plasticity approach; this multi-scale model is used then to investigate grains size, dispersion of grains size, crystallographic texture and slip systems activation effects on Ti-6Al-4V mechanical behavior under monotone quasi-static loading. Nine representative elementary volume (REV) are built for taking into account the physical elements (grains size, dispersion and crystallographic) mentioned above, then boundary conditions of tension test are applied. Finally, simulation of the mechanical behavior of Ti-6Al-4V and study of slip systems activation in alpha phase is reported. The results show that the macroscopic mechanical behavior of Ti-6Al-4V is strongly linked to the active slip systems family (prismatic, basal or pyramidal). The crystallographic texture determines which family of slip systems can be activated; therefore it gives to the plastic strain a heterogeneous character thus an anisotropic macroscopic mechanical behavior of Ti-6Al-4V alloy modeled. The grains size influences also on mechanical proprieties of Ti-6Al-4V, especially on the yield stress; by decreasing of the grain size, the yield strength increases. Finally, the grains' distribution which characterizes the morphology aspect (homogeneous or heterogeneous) gives to the deformation fields distribution enough heterogeneity because the crystallographic slip is easier in large grains compared to small grains, which generates a localization of plastic deformation in certain areas and a concentration of stresses in others.

Keywords: multi-scale modeling, Ti-6Al-4V alloy, crystal plasticity, grains size, crystallographic texture

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508 An Inorganic Nanofiber/Polymeric Microfiber Network Membrane for High-Performance Oil/Water Separation

Authors: Zhaoyang Liu

Abstract:

It has been highly desired to develop a high-performance membrane for separating oil/water emulsions with the combined features of high water flux, high oil separation efficiency, and high mechanical stability. Here, we demonstrated a design for high-performance membranes constructed with ultra-long titanate nanofibers (over 30 µm in length)/cellulose microfibers. An integrated network membrane was achieved with these ultra-long nano/microfibers, contrast to the non-integrated membrane constructed with carbon nanotubes (5 µm in length)/cellulose microfibers. The morphological properties of the prepared membranes were characterized by A FEI Quanta 400 (Hillsboro, OR, United States) environmental scanning electron microscope (ESEM). The hydrophilicity, underwater oleophobicity and oil adhesion property of the membranes were examined using an advanced goniometer (Rame-hart model 500, Succasunna, NJ, USA). More specifically, the hydrophilicity of membranes was investigated by analyzing the spreading process of water into membranes. A filtration device (Nalgene 300-4050, Rochester, NY, USA) with an effective membrane area of 11.3 cm² was used for evaluating the separation properties of the fabricated membranes. The prepared oil-in-water emulsions were poured into the filtration device. The separation process was driven under vacuum with a constant pressure of 5 kPa. The filtrate was collected, and the oil content in water was detected by a Shimadzu total organic carbon (TOC) analyzer (Nakagyo-ku, Kyoto, Japan) to examine the separation efficiency. Water flux (J) of the membrane was calculated by measuring the time needed to collect some volume of permeate. This network membrane demonstrated good mechanical flexibility and robustness, which are critical for practical applications. This network membrane also showed high separation efficiency (99.9%) for oil/water emulsions with oil droplet size down to 3 µm, and meanwhile, has high water permeation flux (6.8 × 10³ L m⁻² h⁻¹ bar⁻¹) at low operation pressure. The high water flux is attributed to the interconnected scaffold-like structure throughout the whole membrane, while the high oil separation efficiency is attributed to the nanofiber-made nanoporous selective layer. Moreover, the economic materials and low-cost fabrication process of this membrane indicate its great potential for large-scale industrial applications.

Keywords: membrane, inorganic nanofibers, oil/water separation, emulsions

Procedia PDF Downloads 146