Search results for: membrane modification
618 Determination and Distribution of Formation Thickness Using Seismic and Well Data in Baga/Lake Sub-basin, Chad Basin Nigeria
Authors: Gabriel Efomeh Omolaiye, Olatunji Seminu, Jimoh Ajadi, Yusuf Ayoola Jimoh
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The Nigerian part of the Chad Basin till date has been one of the few critically studied basins, with few published scholarly works, compared to other basins such as Niger Delta, Dahomey, etc. This work was undertaken by the integration of 3D seismic interpretations and the well data analysis of eight wells fairly distributed in block A, Baga/Lake sub-basin in Borno basin with the aim of determining the thickness of Chad, Kerri-Kerri, Fika, and Gongila Formations in the sub-basin. Da-1 well (type-well) used in this study was subdivided into stratigraphic units based on the regional stratigraphic subdivision of the Chad basin and was later correlated with other wells using similarity of observed log responses. The combined density and sonic logs were used to generate synthetic seismograms for seismic to well ties. Five horizons were mapped, representing the tops of the formations on the 3D seismic data covering the block; average velocity function with maximum error/residual of 0.48% was adopted in the time to depth conversion of all the generated maps. There is a general thickening of sediments from the west to the east, and the estimated thicknesses of the various formations in the Baga/Lake sub-basin are Chad Formation (400-750 m), Kerri-Kerri Formation (300-1200 m), Fika Formation (300-2200 m) and Gongila Formation (100-1300 m). The thickness of the Bima Formation could not be established because the deepest well (Da-1) terminates within the formation. This is a modification to the previous and widely referenced studies of over forty decades that based the estimation of formation thickness within the study area on the observed outcrops at different locations and the use of few well data.Keywords: Baga/Lake sub-basin, Chad basin, formation thickness, seismic, velocity
Procedia PDF Downloads 184617 Microfluidic Impedimetric Biochip and Related Methods for Measurement Chip Manufacture and Counting Cells
Authors: Amina Farooq, Nauman Zafar Butt
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This paper is about methods and tools for counting particles of interest, such as cells. A microfluidic system with interconnected electronics on a flexible substrate, inlet-outlet ports and interface schemes, sensitive and selective detection of cells specificity, and processing of cell counting at polymer interfaces in a microscale biosensor for use in the detection of target biological and non-biological cells. The development of fluidic channels, planar fluidic contact ports, integrated metal electrodes on a flexible substrate for impedance measurements, and a surface modification plasma treatment as an intermediate bonding layer are all part of the fabrication process. Magnetron DC sputtering is used to deposit a double metal layer (Ti/Pt) over the polypropylene film. Using a photoresist layer, specified and etched zones are established. Small fluid volumes, a reduced detection region, and electrical impedance measurements over a range of frequencies for cell counts improve detection sensitivity and specificity. The procedure involves continuous flow of fluid samples that contain particles of interest through the microfluidic channels, counting all types of particles in a portion of the sample using the electrical differential counter to generate a bipolar pulse for each passing cell—calculating the total number of particles of interest originally in the fluid sample by using MATLAB program and signal processing. It's indeed potential to develop a robust and economical kit for cell counting in whole-blood samples using these methods and similar devices.Keywords: impedance, biochip, cell counting, microfluidics
Procedia PDF Downloads 161616 Lucilia Sericata Netrin-A: Secreted by Salivary Gland Larvae as a Potential to Neuroregeneration
Authors: Hamzeh Alipour, Masoumeh Bagheri, Tahereh Karamzadeh, Abbasali Raz, Kourosh Azizi
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Netrin-A, a protein identified for conducting commissural axons, has a similar role in angiogenesis. In addition, studies have shown that one of the netrin-A receptors is expressed in the growing cells of small capillaries. It will be interesting to study this new group of molecules because their role in wound healing will become clearer in the future due to angiogenesis. The greenbottle blowfly Luciliasericata (L. sericata) larvae are increasingly used in maggot therapy of chronic wounds. This aim of this was the identification of moleculareatures of Netrin-A in L. sericata larvae. Larvae were reared under standard maggotarium conditions. The nucleic acid sequence of L. sericataNetrin-A (LSN-A) was then identified using Rapid Amplification of cDNA Ends (RACE) and Rapid Amplification of Genomic Ends (RAGE). Parts of the Netrin-A gene, including the middle, 3′-, and 5′-ends were identified, TA cloned in pTG19 plasmid, and transferred into DH5ɑ Escherichia coli. Each part was sequenced and assembled using SeqMan software. This gene structure was further subjected to in silico analysis. The DNA of LSN-A was identified to be 2407 bp, while its mRNA sequence was recognized as 2115 bp by Oligo0.7 software. It translated the Netrin-A protein with 704 amino acid residues. Its molecular weight is estimated to be 78.6 kDa. The 3-D structure ofNetrin-A drawn by SWISS-MODEL revealed its similarity to the Netrin-1 of humans with 66.8% identity. The LSN-A protein conduces to repair the myelin membrane in neuronal cells. Ultimately, it can be an effective candidate in neural regeneration and wound healing. Furthermore, our next attempt is to deplore recombinant proteins for use in medical sciences.Keywords: maggot therapy, netrin-A, RACE, RAGE, lucilia sericata
Procedia PDF Downloads 109615 Impact of Silicon Surface Modification on the Catalytic Performance Towards CO₂ Conversion of Cu₂S/Si-Based Photocathodes
Authors: Karima Benfadel, Lamia Talbi, Sabiha Anas Boussaa, Afaf Brik, Assia Boukezzata, Yahia Ouadah, Samira Kaci
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In order to prevent global warming, which is mainly caused by the increase in carbon dioxide levels in the atmosphere, it is interesting to produce renewable energy in the form of chemical energy by converting carbon dioxide into alternative fuels and other energy-dense products. Photoelectrochemical reduction of carbon dioxide to value-added products and fuels is a promising and current method. The objective of our study is to develop Cu₂S-based photoélectrodes, in which Cu₂S is used as a CO₂ photoelectrocatalyst deposited on nanostructured silicon substrates. Cu₂S thin layers were deposited using the chemical bath deposition (CBD) technique. Silicon nanowires and nanopyramids were obtained by alkaline etching. SEM and UV-visible spectroscopy was used to analyse the morphology and optical characteristics. By using a potentiostat station, we characterized the photoelectrochemical properties. We performed cyclic voltammetry in the presence and without CO₂ purging as well as linear voltammetry (LSV) in the dark and under white light irradiation. We perform chronoamperometry to study the stability of our photocathodes. The quality of the nanowires and nanopyramids was visible in the SEM images, and after Cu₂S deposition, we could see how the deposition was distributed over the textured surfaces. The inclusion of the Cu₂S layer applied on textured substrates significantly reduces the reflectance (R%). The catalytic performance towards CO₂ conversion of Cu₂S/Si-based photocathodes revealed that the texturing of the silicon surface with nanowires and pyramids has a better photoelectrochemical behavior than those without surface modifications.Keywords: CO₂ conversion, Cu₂S photocathode, silicone nanostructured, electrochemistry
Procedia PDF Downloads 78614 Investigating the Suitability of Utilizing Lyophilized Gels to Improve the Stability of Ufasomes
Authors: Mona Hassan Aburahma, Alaa Hamed Salama
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Ufasomes “unsaturated fatty acids liposomes” are unique nano-sized self-assembled bilayered vesicles that can be easily created from the readily available unsaturated fatty acid. Ufasomes are formed due to weak associative interaction of the fully ionized and unionized fatty acids into bilayers structures. In the ufasomes constructs, the fatty acid molecules are oriented with their hydrocarbon tails directed toward the membrane interior and the carboxyl groups are in contact with water. Although ufasomes can be employed as a safe vesicular carrier for drugs, the extreme instability of their aqueous dispersions hinders their effective use in drug delivery field. Accordingly, in our study, lyophilized gels containing ufasomes were prepared using a simple assembling technique form the readily available oleic acid to overcome the colloidal instability of the ufasomes dispersions and convert them into accurate unit dosage forms. The influence of changing cholesterol percentage relative to oleic acid on the ufasomes vesicles were investigated using factorial design. The optimized oleic acid ufasomes comprised nanoscaled spherical vesicles. Scanning electron micrographs of the lyophilized gels revealed that the included ufasomes were intact, non-aggregating, and preserved their spherical morphology. Rheological characterization (viscosity and shear stress versus shear rate) of reconstituted ufasomal lyophilized gel ensured the ease of application. The capability of the ufasomes, included in the gel, to penetrate deep through the mucosa layers was illustrated using ex-vivo confocal laser imaging, thereby, highlighting the feasibility of stabilizing ufasomes using lyophilized gel platforms.Keywords: ufasomes, lyophilized gel, confocal scanning microscopy, rheological characterization, oleic acid
Procedia PDF Downloads 408613 Oral Health Status in Sickle Cell Anemia Subjects
Authors: Surekha Rathod
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Sickle cell disease is a vascular disorder characterized by chronic, ongoing organ damage that is punctuated by episodes of acutely painful vascular complications.1 It is the most common genetic blood disorder in the United States, with about 2000 infants being identified through routine blood screenings annually, and an estimated 104,000-138,000 affected individuals living in the United States. Approximately 0.3%-1.3% of African American are affected by Sickle Cell Diseases (SCD).3 The aim of this paper is to present oral health status of patients with SCD. A total of 200 subjects of both sexes in the age group 18- 40 years were included in this study. The subjects were examined and the following indices were recorded • Oral hygiene index – Simplified (OHI-S). • Probing depths (PD). • Clinical Attachment Levels (CAL). • Gingival Index - Loe and Sillness. • Turesky Gillmore Glickman Modification of the Quigley Hein Plaque Index. (1970) • DMFT index. • Sickle Cell Disease Severity Index. A total of 1478 patients were screened of which 200 subjects were found to be diagnosed with SCD by electrophoresis. The study thus, included 200 subjects (111 females & 89 males) diagnosed with Sickle Cell Disease in the age group of 18-40 years. The probing pocket depths (PPD) were measured in millimeters. 36% had PPD in the range of 2-4mm, 48% had PPD in the range of 4-6mm while 16% had PPD of more than 6mm. Similar results were obtained for the Clinical Attachment Levels (CAL). 29.5 % subjects had CAL 2-4mm, 44.5% had 4-6mm & 26% had CAL 6mm & above. We can thus conclude that although oral health is not a priority for patients with SCD, it is supported by increased plaque accumulation. Because of the chronic anemic state of the patients with SCD, they should be encouraged to pay strict attention to oral hygiene instructions and practice.Keywords: chronic, genetic, oral, sickle cell disease, vascular
Procedia PDF Downloads 398612 Economic Assessment of CO2-Based Methane, Methanol and Polyoxymethylene Production
Authors: Wieland Hoppe, Nadine Wachter, Stefan Bringezu
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Carbon dioxide (CO2) utilization might be a promising way to substitute fossil raw materials like coal, oil or natural gas as carbon source of chemical production. While first life cycle assessments indicate a positive environmental performance of CO2-based process routes, a commercialization of CO2 is limited by several economic obstacles up to now. We, therefore, analyzed the economic performance of the three CO2-based chemicals methane and methanol as basic chemicals and polyoxymethylene as polymer on a cradle-to-gate basis. Our approach is oriented towards life cycle costing. The focus lies on the cost drivers of CO2-based technologies and options to stimulate a CO2-based economy by changing regulative factors. In this way, we analyze various modes of operation and give an outlook for the potentially cost-effective development in the next decades. Biogas, waste gases of a cement plant, and flue gases of a waste incineration plant are considered as CO2-sources. The energy needed to convert CO2 into hydrocarbons via electrolysis is assumed to be supplied by wind power, which is increasingly available in Germany. Economic data originates from both industrial processes and process simulations. The results indicate that CO2-based production technologies are not competitive with conventional production methods under present conditions. This is mainly due to high electricity generation costs and regulative factors like the German Renewable Energy Act (EEG). While the decrease in production costs of CO2-based chemicals might be limited in the next decades, a modification of relevant regulative factors could potentially promote an earlier commercialization.Keywords: carbon capture and utilization (CCU), economic assessment, life cycle costing (LCC), power-to-X
Procedia PDF Downloads 290611 Oxidosqualene Cyclase: A Novel Inhibitor
Authors: Devadrita Dey Sarkar
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Oxidosqualene cyclase is a membrane bound enzyme in which helps in the formation of steroid scaffold in higher organisms. In a highly selective cyclization reaction oxidosqualene cyclase forms LANOSTEROL with seven chiral centres starting from the linear substrate 2,3-oxidosqualene. In humans OSC in cholesterol biosynthesis it represents a target for the discovery of novel anticholesteraemic drugs that could complement the widely used statins. The enzyme oxidosqualene: lanosterol cyclase (OSC) represents a novel target for the treatment of hypercholesterolemia. OSC catalyzes the cyclization of the linear 2,3-monoepoxysqualene to lanosterol, the initial four-ringed sterol intermediate in the cholesterol biosynthetic pathway. OSC also catalyzes the formation of 24(S), 25-epoxycholesterol, a ligand activator of the liver X receptor. Inhibition of OSC reduces cholesterol biosynthesis and selectively enhances 24(S),25-epoxycholesterol synthesis. Through this dual mechanism, OSC inhibition decreases plasma levels of low-density lipoprotein (LDL)-cholesterol and prevents cholesterol deposition within macrophages. The recent crystallization of OSC identifies the mechanism of action for this complex enzyme, setting the stage for the design of OSC inhibitors with improved pharmacological properties for cholesterol lowering and treatment of atherosclerosis. While studying and designing the inhibitor of oxidosqulene cyclase, I worked on the pdb id of 1w6k which was the most worked on pdb id and I used several methods, techniques and softwares to identify and validate the top most molecules which could be acting as an inhibitor for oxidosqualene cyclase. Thus, by partial blockage of this enzyme, both an inhibition of lanosterol and subsequently cholesterol formation as well as a concomitant effect on HMG-CoA reductase can be achieved. Both effects complement each other and lead to an effective control of cholesterol biosynthesis. It is therefore concluded that 2,3-oxidosqualene cyclase plays a crucial role in the regulation of intracellular cholesterol homeostasis. 2,3-Oxidosqualene cyclase inhibitors offer an attractive approach for novel lipid-lowering agents.Keywords: anticholesteraemic, crystallization, statins, homeostasis
Procedia PDF Downloads 351610 Variation In Gastrocnemius and Hamstring Muscle Activity During Peak Knee Flexor Torque After Anterior Cruciate Ligament Reconstruction with Hamstring Graft
Authors: Luna Sequier, Florian Forelli, Maude Traulle, Amaury Vandebrouck, Pascal Duffiet, Louis Ratte, Jean Mazeas
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The study's objective is to compare the muscular activity of the flexor knee muscle in patients who underwent an anterior cruciate ligament reconstruction with hamstring autograft and the individuals who have not undergone surgery. Methods: The participants were divided into two groups: a healthy group and an experimental group who had undergone an anterior cruciate ligament reconstruction with a hamstring graft. All participants had to perform a knee flexion strength test on an isokinetic dynamometer. The medial Gastrocnemius, lateral Gastrocnemius, Biceps femoris, and medial Hamstring muscle activity were measured during this test. Each group’s mean muscle activity was tested with statistical analysis, and a muscle activity ratio of gastrocnemius and hamstring muscles was calculated Results: The results showed a significant difference in activity of the medial gastrocnemius (p = 0,004901), the biceps femoris (p = 5,394.10-6), and the semitendinosus muscles (p = 1,822.10-6), with a higher Biceps femoris and Semitendinosus activity for the experimental group. It is however noticeable that inter-subject differences were important. Conclusion: This study has shown a difference in the gastrocnemius and hamstring muscle activity between patients who underwent an anterior cruciate ligament reconstruction surgery and healthy participants. With further results, this could show a modification of muscle activity patterns after surgery which could lead to compensatory behaviors at a return to sport and eventually explain a higher injury risk for our patients.Keywords: anterior cruciate ligament, electromyography, muscle activity, physiotherapy
Procedia PDF Downloads 241609 Evaluating the Impact of Expansion on Urban Thermal Surroundings: A Case Study of Lahore Metropolitan City, Pakistan
Authors: Usman Ahmed Khan
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Urbanization directly affects the existing infrastructure, landscape modification, environmental contamination, and traffic pollution, especially if there is a lack of urban planning. Recently, the rapid urban sprawl has resulted in less developed green areas and has devastating environmental consequences. This study was aimed to study the past urban expansion rates and measure LST from satellite data. The land use land cover (LULC) maps of years 1996, 2010, 2013, and 2017 were generated using landsat satellite images. Four main classes, i.e., water, urban, bare land, and vegetation, were identified using unsupervised classification with iterative self-organizing data analysis (isodata) technique. The LST from satellite thermal data can be derived from different procedures: atmospheric, radiometric calibrations and surface emissivity corrections, classification of spatial changeability in land-cover. Different methods and formulas were used in the algorithm that successfully retrieves the land surface temperature to help us study the thermal environment of the ground surface. To verify the algorithm, the land surface temperature and the near-air temperature were compared. The results showed that, From 1996-2017, urban areas increased to about a considerable increase of about 48%. Few areas of the city also shown in a reduction in LST from the year 1996-2017 that actually began their transitional phase from rural to urban LULC. The mean temperature of the city increased averagely about 1ºC each year in the month of October. The green and vegetative areas witnessed a decrease in the area while a higher number of pixels increased in urban class.Keywords: LST, LULC, isodata, urbanization
Procedia PDF Downloads 100608 Antifungal Susceptibility of Saprolegnia parasitica Isolated from Rainbow Trout and Its Host Pathogen Interaction in Zebrafish Disease Model
Authors: Sangyeop Shin, D. C. M. Kulatunga, S. H. S. Dananjaya, Chamilani Nikapitiya, Jehee Lee, Mahanama De Zoysa
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Saprolegniasis is one of the most devastating fungal diseases in freshwater fish which is caused by species in the genus Saprolegnia including Saprolegnia parasitica. In this study, we isolated the strain of S. parasitica from diseased rainbow trout in Korea. Morphological and molecular based identification confirmed that isolated fungi belong to the member of S. parasitica, supported by its typical fungal features including cotton-like whitish mycelium, zoospores (primary and secondary) and phylogenetic analysis with internal transcribed spacer (ITS) region. Pathogenicity of isolated S. parasitica was developed in embryo, larvae, juvenile and adult zebrafish as a disease model. Up regulation of host genes encoding ZfTnf-α, Zfc-Rel, ZfIl-12, ZfLyz-c, Zfβ-def, and ZfHsp-70 was identified in zebrafish larvae after experimental challenge of S. parasitica showing the host immune responses against the S. parasitica. Survival of the juveniles upon fungal infection might be due to the increased immune protection in the host. Investigation of antifungal susceptibility of S. parasitica with natural lawsone (2-hydroxy-1,4-naphthoquinone) revealed the minimum inhibitory concentration (MIC) and percentage inhibition of radial growth (PIRG %) as 200 µg/mL and 31.8%, respectively. Lawsone was able to change the membrane permeability, and cause irreversible damage and disintegration to the cellular membranes of S. parasitica which might have effect on fungi growth inhibition. Moreover, the mycelium exposed to lawsone (MIC level) changed the transcriptional responses of S. parasitica genes. Overall results indicate that lawsone could be a potential and novel anti-S. parasitica agent for controlling S. parasitica infection.Keywords: host-pathogen interactions, lawsone, rainbow trout, Saprolegnia parasitica, Saprolegniasis, zebrafish
Procedia PDF Downloads 248607 A Handheld Light Meter Device for Methamphetamine Detection in Oral Fluid
Authors: Anindita Sen
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Oral fluid is a promising diagnostic matrix for drugs of abuse compared to urine and serum. Detection of methamphetamine in oral fluid would pave way for the easy evaluation of impairment in drivers during roadside drug testing as well as ensure safe working environments by facilitating evaluation of impairment in employees at workplaces. A membrane-based point-of-care (POC) friendly pre-treatment technique has been developed which aided elimination of interferences caused by salivary proteins and facilitated the demonstration of methamphetamine detection in saliva using a gold nanoparticle based colorimetric aptasensor platform. It was found that the colorimetric response in saliva was always suppressed owing to the matrix effects. By navigating the challenging interfering issues in saliva, we were successfully able to detect methamphetamine at nanomolar levels in saliva offering immense promise for the translation of these platforms for on-site diagnostic systems. This subsequently motivated the development of a handheld portable light meter device that can reliably transduce the aptasensors colorimetric response into absorbance, facilitating quantitative detection of analyte concentrations on-site. This is crucial due to the prevalent unreliability and sensitivity problems of the conventional drug testing kits. The fabricated light meter device response was validated against a standard UV-Vis spectrometer to confirm reliability. The portable and cost-effective handheld detector device features sensitivity comparable to the well-established UV-Vis benchtop instrument and the easy-to-use device could potentially serve as a prototype for a commercial device in the future.Keywords: aptasensors, colorimetric gold nanoparticle assay, point-of-care, oral fluid
Procedia PDF Downloads 59606 Prevalence of Cutaneous Leishmaniasis in Human Population of District Kurram, Khyber Pakhtunkhwa, Pakistan
Authors: Shah Abid
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Leishmaniasis is a collection of zoonotic infections that affect the viscera, skin, and mucous membrane and are spread by several species of female sandflies in the subfamily phlebotominae. The study's goal was to assess the prevalence of Cutaneous Leishmaniasis in District Kurram using descriptive and cross-sectional methods. From December 2022 to May 2023, the study was carried out at Tehsil Head Quarter (THQ) Hospital, Sadda, District Kurram in the Dermatology Department. The disease was identified using a laboratory method based on clinical manifestations of leishmaniasis. A clean slide's surface was applied to the scraped-off portion of the lesions and rubbed over the blood to make a smear on the slide. The slides were methanol-fixed, stained with traditional Giemsa, and meticulously examined at high magnification to search for LD bodies. The necessary information, such as residence area, lesion kind and location, age, sex, and the total number of lesions, was meticulously acquired. During the time of the investigation, 393 instances of cutaneous leishmaniasis were observed. 1 year to 70 years old was the age range (mean age: 35.45). The age group that was most severely impacted, 16 years and older, had 23 (11.67%) children with this condition. Male to female ratio was 9.7:10. Most of the cases (n=52, 26.29%), were reported in the month of May. Majority of the patients 102 (51.77%) had lesion on face. 42 (16.73) patients had multiple lesions on their body. Face was the most common site followed by lower limbs 93 (37.05). Weekly intralesional injections of sodium stibogluconate (glucantime) were administered to all patients. Without any noticeable adverse effects, all patients had positive responses to the treatment. The condition affects adults more commonly than children, according to analysis of the combined results, and it is more common in women than in men.Keywords: District Kurram, cutaneous leishmaniasis, zoonosis, glucantime
Procedia PDF Downloads 9605 Analysis of Rockfall Hazard along Himalayan Road Cut Slopes
Authors: Sarada Prasad Pradhan, Vikram Vishal, Tariq Siddique
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With a vast area of India comprising of hilly terrain and road cut slopes, landslides and rockfalls are a common phenomenon. However, while landslide studies have received much attention in the past in India, very little literature and analysis is available regarding rockfall hazard of many rockfall prone areas, specifically in Uttarakhand Himalaya, India. The subsequent lack of knowledge and understanding of the rockfall phenomenon as well as frequent incidences of rockfall led fatalities urge the necessity of conducting site-specific rockfall studies to highlight the importance of addressing this issue as well as to provide data for safe design of preventive structures. The present study has been conducted across 10 rockfall prone road cut slopes for a distance of 15 km starting from Devprayag, India along National Highway 58 (NH-58). In order to make a qualitative assessment of Rockfall Hazard posed by these slopes, Rockfall Hazard Rating using standards for Indian Rockmass has been conducted at 10 locations under different slope conditions. Moreover, to accurately predict the characteristics of the possible rockfall phenomenon, numerical simulation was carried out to calculate the maximum bounce heights, total kinetic energies, translational velocities and trajectories of the falling rockmass blocks when simulated on each of these slopes according to real-life conditions. As it was observed that varying slope geometry had more fatal impacts on Rockfall hazard than size of rock masses, several optimizations have been suggested for each slope regarding location of barriers and modification of slope geometries in order to minimize damage by falling rocks. This study can be extremely useful in emphasizing the significance of rockfall studies and construction of mitigative barriers and structures along NH-58 around Devprayag.Keywords: rockfall, slope stability, rockmass, hazard
Procedia PDF Downloads 208604 Effect of Electromagnetic Radiation on Reproductive System of Male Rat
Authors: Rohit Gautam, Kumari Vandana Singh, Jayprakash Nirala, Nina Nancy Murmu, Ramovatar Meena, Paulraj Rajamani
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Mobile phones have become a vital part of everyone’s life. Mobile phone and mobile phone towers emit RF-EMR (Radiofrequency Electromagnetic Radiation), which becomes a cause of concern to the general public. The study was designed to evaluate the effect of 3G (RF-EMR) on the reproductive system of male Wistar rats. Adult male Wistar rats were used for the study. Animals were divided into two groups, RF-exposed, and sham-exposed (control). RF-exposed rats were exposed to radio frequency radiation (2100 MHz) for 2 hours/day for 45 days. Emitted power density and specific absorption rate (SAR) values were measured during exposure. At the end of the exposure, testis and epididymis were excised out, and their weights were recorded. Sperm cell count, morphology, viability, and reactive oxygen species (ROS) levels were checked. Lipid peroxidation and sperm mitochondrial activity were measured. Histopathology of testis and ultrastructure analysis of sperm were also checked. Result showed a decrease in organ weight and sperm count with alteration in the sperm morphology in exposed group rats. A significant decrease in sperm viability, membrane integrity, and mitochondrial activity was found. Also, an increase in lipid peroxidation and ROS level were found in exposed group animals as compared to control. It may be concluded that exposure to radiofrequency radiation emits from mobile phones leads to oxidative stress-mediated changes in reproductive parameters.Keywords: electromagnetic radiation, oxidative stress, reactive oxygen species, sperm
Procedia PDF Downloads 178603 Fabrication and Characterization of Folic Acid-Grafted-Thiomer Enveloped Liposomes for Enhanced Oral Bioavailability of Docetaxel
Authors: Farhan Sohail, Gul Shahnaz Irshad Hussain, Shoaib Sarwar, Ibrahim Javed, Zajif Hussain, Akhtar Nadhman
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The present study was aimed to develop a hybrid nanocarrier (NC) system with enhanced membrane permeability, bioavailability and targeted delivery of Docetaxel (DTX) in breast cancer. Hybrid NC’s based on folic acid (FA) grafted thiolated chitosan (TCS) enveloped liposomes were prepared with DTX and evaluated in-vitro and in-vivo for their enhanced permeability and bioavailability. Physicochemical characterization of NC’s including particle size, morphology, zeta potential, FTIR, DSC, PXRD, encapsulation efficiency and drug release from NC’s was determined in vitro. Permeation enhancement and p-gp inhibition were performed through everted sac method on freshly excised rat intestine which indicated that permeation was enhanced 5 times as compared to pure DTX and the hybrid NC’s were strongly able to inhibit the p-gp activity as well. In-vitro cytotoxicity and tumor targeting was done using MDA-MB-231 cell line. The stability study of the formulations performed for 3 months showed the improved stability of FA-TCS enveloped liposomes in terms of its particles size, zeta potential and encapsulation efficiency as compared to TCS NP’s and liposomes. The pharmacokinetic study was performed in vivo using rabbits. The oral bioavailability and AUC0-96 was increased 10.07 folds with hybrid NC’s as compared to positive control. Half-life (t1/2) was increased 4 times (58.76 hrs) as compared to positive control (17.72 hrs). Conclusively, it is suggested that FA-TCS enveloped liposomes have strong potential to enhance permeability and bioavailability of hydrophobic drugs after oral administration and tumor targeting.Keywords: docetaxel, coated liposome, permeation enhancement, oral bioavailability
Procedia PDF Downloads 408602 Anti-inflammatory and Hemostatic Activities of Methanolic Extract from Atriplex Halimus. Leaves
Authors: Yahia Massinissa, Benhouda Afaf, Benbia Souhila, Meddour Noura, Takellalet Karima, Zeroual Amina
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Introduction: chenopodiaceae family species are known for their important biological activity, in which Atriplex halimus belongs . However, the inflammatory effect of this plant leaves has not been studied. This work aimed at assessing the anti- inflammatory and hemostatic activities of the methanolic extract AHMeOH of Atriplex halimus’s leaves. Methods: The extract was obtained using sonication of leaves powder in 80 % methanol. The analysis of phenolic compounds was carried out using thin-layer chromatography (TLC).The anti-inflammatory activity was determined by studying the plasmical membrane stabilization and albumin denaturation inhibition, the hemostatic activity was evaluated by measuring the plasma in the blood. Results: Quantitative determination of total flavonoids reveals that AHMeOH is rich in flavonoids (16 ± 0.88 μg Q / mg extract) and polyphenols (20 ± 0.20 μg AG / mg extract). about anti-inflammatory activity, the tests show that AHMeOH has a significant effect (P≤0.05) of inhibiting hypotonic-induced hemolysis with concentrations (100 and 200 μg / ml) with 77.55 and 90% respectively, and heat-induced hemolysis with percentages 81.75% and 87.44% respectively with significant difference (P ≤0.05). The obtained results with this plant reveal that the inhibition of denaturation of albumin is dose dependent. The concentration of 400 μg / ml gives denaturation inhibition of 81.00 ± 17.70% and the concentration 600 μg / ml gives an effect of 82.95 ± 17.40%. Regarding the haemostatic activity our extract with the doses 10 mg / ml, 20 mg / ml and 30 mg / ml confer a decrease of the plasma recalcification time in the tube, these concentrations could prolong the time of coagulation significantly compared to the control (P≤0.001). This result is an interesting indication in favor of haemostatic activity of AHMeOH. Conclusion: Atriplex Halimus has a strong anti-inflammatory activity and constitutes a potential source for the development of new treatments.Keywords: albumin, atriplex halimus, hemostatic activity, methanolic extract
Procedia PDF Downloads 75601 Mathematical Modelling, Simulation and Prototype Designing of Potable Water System on Basis of Forward Osmosis
Authors: Ridhish Kumar, Sudeep Nadukkandy, Anirban Roy
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The development of reverse osmosis happened in 1960. Along the years this technique has been widely accepted all over the world for varied applications ranging from seawater desalination to municipal water treatment. Forward osmosis (FO) is one of the foremost technologies for low energy consuming solutions for water purification. In this study, we have carried out a detailed analysis on selection, design, and pricing for a prototype of potable water system for purifying water in emergency situations. The portable and light purification system is envisaged to be driven by FO. This pouch will help to serve as an emergency water filtration device. The current effort employs a model to understand the interplay of permeability and area on the rate of purification of water from any impure source/brackish water. The draw solution for the FO pouch is considered to be a combination of salt and sugar such that dilution of the same would result in an oral rehydration solution (ORS) which is a boon for dehydrated patients. However, the effort takes an extra step to actually estimate the cost and pricing of designing such a prototype. While the mathematical model yields the best membrane (compositions are taken from literature) combination in terms of permeability and area, the pricing takes into account the feasibility of such a solution to be made available as a retail item. The product is envisaged to be a market competitor for packaged drinking water and ORS combination (costing around $0.5 combined) and thus, to be feasible has to be priced around the same range with greater margins in order to have a better distribution. Thus a proper business plan and production of the same has been formulated in order to be a feasible solution for unprecedented calamities and emergency situations.Keywords: forward osmosis, water treatment, oral rehydration solution, prototype
Procedia PDF Downloads 184600 A Decision Making Tool for Selecting the Most Environmental Friendly Wastewater Treatment Plant for Small-Scale Communities
Authors: Mehmet Bulent Topkaya, Mustafa Yildirim
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Wastewater treatment systems are designed and used to minimize adverse impacts of the wastewater on the environment before discharging. Various treatment options for wastewater treatment have been developed, and each of them has different performance characteristics and environmental impacts (e.g. material and land usage, energy consumption, greenhouse gas emission, water and soil emission) during construction, operation or maintenance phases. Assessing the environmental impacts during these phases are essential for the overall evaluation of the treatment systems. In this study, wastewater treatment options, such as vegetated land treatment, constructed wetland, rotating biological contactor, conventional activated sludge treatment, membrane bioreactor, extended aeration and stabilization pond are evaluated. The comparison of the environmental impacts is conducted under the assumption that the effluents will be discharged to sensitive and less sensitive areas respectively. The environmental impacts of each alternative are evaluated by life cycle assessment (LCA) approach. For this purpose, data related to energy usage, land requirement, raw material consumption, and released emissions from the life phases were collected with inventory studies based on field studies and literature. The environmental impacts were assessed by using SimaPro 7.1 LCA software. As the scale of the LCA results is global, an MS-Excel based decision support tool that includes the LCA result is developed in order to meet also the local demands. Using this tool, it is possible to assign weight factors on the LCA results according to local conditions by using Analytical Hierarchy Process and finally the most environmentally appropriate treatment option can be selected.Keywords: analytical hierarchy process, decision support system, life cycle assessment, wastewater treatment
Procedia PDF Downloads 301599 Effects of Duct Geometry, Thickness and Types of Liners on Transmission Loss for Absorptive Silencers
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Sound attenuation in absorptive silencers has been analyzed in this paper. The structure of such devices is as follows. When the rigid duct of an expansion chamber has been lined by a packed absorptive material under a perforated membrane, incident sound waves will be dissipated by the absorptive liners. This kind of silencer, usually are applicable for medium to high frequency ranges. Several conditions for different absorptive materials, variety in their thicknesses, and different shapes of the expansion chambers have been studied in this paper. Also, graphs of sound attenuation have been compared between empty expansion chamber and duct of silencer with applying liner. Plane waves have been assumed in inlet and outlet regions of the silencer. Presented results that have been achieved by applying finite element method (FEM), have shown the dependence of the sound attenuation spectrum to flow resistivity and the thicknesses of the absorptive materials, and geometries of the cross section (configuration of the silencer). As flow resistivity and thickness of absorptive materials increase, sound attenuation improves. In this paper, diagrams of the transmission loss (TL) for absorptive silencers in five different cross sections (rectangle, circle, ellipse, square, and rounded rectangle as the main geometry) have been presented. Also, TL graphs for silencers using different absorptive material (glass wool, wood fiber, and kind of spongy materials) as liner with three different thicknesses of 5 mm, 15 mm, and 30 mm for glass wool liner have been exhibited. At first, the effect of substances of the absorptive materials with the specific flow resistivity and densities on the TL spectrum, then the effect of the thicknesses of the glass wool, and at last the efficacy of the shape of the cross section of the silencer have been investigated.Keywords: transmission loss, absorptive material, flow resistivity, thickness, frequency
Procedia PDF Downloads 250598 Effect of Extrusion Processing Parameters on Protein in Banana Flour Extrudates: Characterisation Using Fourier-Transform Infrared Spectroscopy
Authors: Surabhi Pandey, Pavuluri Srinivasa Rao
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Extrusion processing is a high-temperature short time (HTST) treatment which can improve protein quality and digestibility together with retaining active nutrients. In-vitro protein digestibility of plant protein-based foods is generally enhanced by extrusion. The current study aimed to investigate the effect of extrusion cooking on in-vitro protein digestibility (IVPD) and conformational modification of protein in green banana flour extrudates. Green banana flour was extruded through a co-rotating twin-screw extruder varying the moisture content, barrel temperature, screw speed in the range of 10-20 %, 60-80 °C, 200-300 rpm, respectively, at constant feed rate. Response surface methodology was used to optimise the result for IVPD. Fourier-transform infrared spectroscopy (FTIR) analysis provided a convenient and powerful means to monitor interactions and changes in functional and conformational properties of extrudates. Results showed that protein digestibility was highest in extrudate produced at 80°C, 250 rpm and 15% feed moisture. FTIR analysis was done for the optimised sample having highest IVPD. FTIR analysis showed that there were no changes in primary structure of protein while the secondary protein structure changed. In order to explain this behaviour, infrared spectroscopy analysis was carried out, mainly in the amide I and II regions. Moreover, curve fitting analysis showed the conformational changes produced in the flour due to protein denaturation. The quantitative analysis of the changes in the amide I and II regions provided information about the modifications produced in banana flour extrudates.Keywords: extrusion, FTIR, protein conformation, raw banana flour, SDS-PAGE method
Procedia PDF Downloads 162597 Experimental and Numerical Study on the Effects of Oxygen Methane Flames with Water Dilution for Different Pressures
Authors: J. P. Chica Cano, G. Cabot, S. de Persis, F. Foucher
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Among all possibilities to combat global warming, CO2 capture and sequestration (CCS) is presented as a great alternative to reduce greenhouse gas (GHG) emission. Several strategies for CCS from industrial and power plants are being considered. The concept of combined oxy-fuel combustion has been the most alternative solution. Nevertheless, due to the high cost of pure O2 production, additional ways recently emerged. In this paper, an innovative combustion process for a gas turbine cycle was studied: it was composed of methane combustion with oxygen enhanced air (OEA), exhaust gas recirculation (EGR) and H2O issuing from STIG (Steam Injection Gas Turbine), and the CO2 capture was realized by membrane separator. The effect on this combustion process was emphasized, and it was shown that a study of the influence of H2O dilution on the combustion parameters by experimental and numerical approaches had to be carried out. As a consequence, the laminar burning velocities measurements were performed in a stainless steel spherical combustion from atmospheric pressure to high pressure (up to 0.5 MPa), at 473 K for an equivalence ratio at 1. These experimental results were satisfactorily compared with Chemical Workbench v.4.1 package in conjunction with GRIMech 3.0 reaction mechanism. The good correlations so obtained between experimental and calculated flame speed velocities showed the validity of the GRIMech 3.0 mechanism in this domain of combustion: high H2O dilution, low N2, medium pressure. Finally, good estimations of flame speed and pollutant emissions were determined in other conditions compatible with real gas turbine. In particular, mixtures (composed of CH4/O2/N2/H2O/ or CO2) leading to the same adiabatic temperature were investigated. Influences of oxygen enrichment and H2O dilution (compared to CO2) were disused.Keywords: CO₂ capture, oxygen enrichment, water dilution, laminar burning velocity, pollutants emissions
Procedia PDF Downloads 166596 Synergistic Effect of Curcumin and Insulin on GLUT4 Translocation in C2C12 Cell
Authors: Javad Mohiti-Ardekani, Shabodin Asadii, Ali Moradi
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Introduction: Curcumin, the yellow pigment in turmeric, has been shown as an anti-diabetic agent for centuries but only in recent few years, its mechanism of action has been under investigation. Some studies showed that curcumin might exert its anti-diabetic effect via increasing glucose transporter isotype-4 (GLUT4) gene and glycoprotein contents in cells. To investigate this possibility, we investigate the effects of extract and commercial curcumin with and without insulin on GLUT4 translocation from intracellular compartments of nuclear or endoplasmic reticulum membranes (N/ER) into the cytoplasmic membrane (CM). Methods and Material: C2C12 myoblastic cell line were seeded in DMEM plus 20 % FBS and differentiated to myotubes using 2 % horse serum. After myotubes formation, 40 µmolar Extract and Commercial curcumin, with or without insulin as intervention, and as control 1 % DMSO were added for 3 h. Cells were washed and homogenized followed by ultracentrifuge fractionation, protein separation by SDS-PAGE and GLUT4 detection using semi-quantitative Western blotting. Data analysis was done by two independent samples t-test for comparison of mean ± SD of GLUT4 percent in categories. GLUT4 contents were higher in CM groups curcumin and curcumin with insulin in comparison to 1 % DMSO-treated myotubes control group. Results: As our results have shown extract and commercial curcumin induces GLUT4 translocation from intra-cell into cell surface. The results have also shown synergic effect of curcumin on translocation of GLUT4 from intra-cell into cell surface in the presence of 100 nm insulin. Discussion: We conclude that curcumin may be a choice of type-2 diabetes mellitus treatment because its extract and commercial enhances GLUT4 contents in CM where it facilitates glucose entrance into the cell. However, it is necessary to trace the signaling pathways which are activated by curcumin.Keywords: Curcumin, insulin, Diabetes type-2, GLUT4
Procedia PDF Downloads 243595 Modeling and Temperature Control of Water-cooled PEMFC System Using Intelligent Algorithm
Authors: Chen Jun-Hong, He Pu, Tao Wen-Quan
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Proton exchange membrane fuel cell (PEMFC) is the most promising future energy source owing to its low operating temperature, high energy efficiency, high power density, and environmental friendliness. In this paper, a comprehensive PEMFC system control-oriented model is developed in the Matlab/Simulink environment, which includes the hydrogen supply subsystem, air supply subsystem, and thermal management subsystem. Besides, Improved Artificial Bee Colony (IABC) is used in the parameter identification of PEMFC semi-empirical equations, making the maximum relative error between simulation data and the experimental data less than 0.4%. Operation temperature is essential for PEMFC, both high and low temperatures are disadvantageous. In the thermal management subsystem, water pump and fan are both controlled with the PID controller to maintain the appreciate operation temperature of PEMFC for the requirements of safe and efficient operation. To improve the control effect further, fuzzy control is introduced to optimize the PID controller of the pump, and the Radial Basis Function (RBF) neural network is introduced to optimize the PID controller of the fan. The results demonstrate that Fuzzy-PID and RBF-PID can achieve a better control effect with 22.66% decrease in Integral Absolute Error Criterion (IAE) of T_st (Temperature of PEMFC) and 77.56% decrease in IAE of T_in (Temperature of inlet cooling water) compared with traditional PID. In the end, a novel thermal management structure is proposed, which uses the cooling air passing through the main radiator to continue cooling the secondary radiator. In this thermal management structure, the parasitic power dissipation can be reduced by 69.94%, and the control effect can be improved with a 52.88% decrease in IAE of T_in under the same controller.Keywords: PEMFC system, parameter identification, temperature control, Fuzzy-PID, RBF-PID, parasitic power
Procedia PDF Downloads 85594 Dealing with Buckling Effect in Snorkel by Finite Element Analysis: A Life Enhancement Approach in CAS-OB Operation
Authors: Subodh Nath Patel, Raja Raman, Mananshi Adhikary, Jitendra Mathur, Sandip Bhattacharyya
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The composition adjustment by sealed argon bubbling–oxygen blowing (CAS-OB) process is a process designed for adjusting steel composition and temperature during secondary metallurgy. One of the equipment in the said process is a snorkel or bell, fixed to a movable bracket. Snorkel serves the purpose of feeding ferroalloys into the liquid metal simultaneously removing gases to the gas cleaning system through its port at its top. The bell-shaped snorkel consists of two parts. The upper part has an inside liner, and the lower part is lined on both side with high-alumina castable reinforced with 2% stainless steel needles. Both the parts are coupled with a flange bolt system. These flanges were found to get buckled during operation, and the gap was generating between them. This problem was chronic since its. It was expected to give a life of 80 heats, but it was failing within 45-50 heats. After every 25-30 heats, it had to be repaired by changing and/or tightening its nuts and bolts. Visual observation, microstructural analysis through optical microscopes and SEM, hardness measurement and thermal strain calculation were carried out to find out the root cause of this problem. The calculated thermal strain was compared with actual thermal strain; comparison of the two revealed that thermal strain was responsible for buckling. Finite element analysis (FEA) was carried out to reaffirm the effect temperature on the flanges. FEA was also used in the modification in the design of snorkel flange to accommodate thermal strain. Thermal insulation was also recommended which increased its life from 45 heats to 65 heats, impacting business process positively.Keywords: CAS OB process, finite element analysis, snorkel, thermal strain
Procedia PDF Downloads 137593 Enhanced Optical Nonlinearity in Bismuth Borate Glass: Effect of Size of Nanoparticles
Authors: Shivani Singla, Om Prakash Pandey, Gopi Sharma
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Metallic nanoparticle doped glasses has lead to rapid development in the field of optics. Large third order non-linearity, ultrafast time response, and a wide range of resonant absorption frequencies make these metallic nanoparticles more important in comparison to their bulk material. All these properties are highly dependent upon the size, shape, and surrounding environment of the nanoparticles. In a quest to find a suitable material for optical applications, several efforts have been devoted to improve the properties of such glasses in the past. In the present study, bismuth borate glass doped with different size gold nanoparticles (AuNPs) has been prepared using the conventional melt-quench technique. Synthesized glasses are characterized by X-ray diffraction (XRD) and Fourier Transformation Infrared spectroscopy (FTIR) to observe the structural modification in the glassy matrix with the variation in the size of the AuNPs. Glasses remain purely amorphous in nature even after the addition of AuNPs, whereas FTIR proposes that the main structure contains BO₃ and BO₄ units. Field emission scanning electron microscopy (FESEM) confirms the existence and variation in the size of AuNPs. Differential thermal analysis (DTA) depicts that prepared glasses are thermally stable and are highly suitable for the fabrication of optical fibers. The nonlinear optical parameters (nonlinear absorption coefficient and nonlinear refractive index) are calculated out by using the Z-scan technique with a Ti: sapphire laser at 800 nm. It has been concluded that the size of the nanoparticles highly influences the structural thermal and optical properties system.Keywords: bismuth borate glass, different size, gold nanoparticles, nonlinearity
Procedia PDF Downloads 122592 Drawing Building Blocks in Existing Neighborhoods: An Automated Pilot Tool for an Initial Approach Using GIS and Python
Authors: Konstantinos Pikos, Dimitrios Kaimaris
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Although designing building blocks is a procedure used by many planners around the world, there isn’t an automated tool that will help planners and designers achieve their goals with lesser effort. The difficulty of the subject lies in the repeating process of manually drawing lines, while not only it is mandatory to maintain the desirable offset but to also achieve a lesser impact to the existing building stock. In this paper, using Geographical Information Systems (GIS) and the Python programming language, an automated tool integrated into ArcGIS PRO, is being presented. Despite its simplistic enviroment and the lack of specialized building legislation due to the complex state of the field, a planner who is aware of such technical information can use the tool to draw an initial approach of the final building blocks in an area with pre-existing buildings in an attempt to organize the usually sprawling suburbs of a city or any continuously developing area. The tool uses ESRI’s ArcPy library to handle the spatial data, while interactions with the user is made throught Tkinter. The main process consists of a modification of building edgescoordinates, using NumPy library, in an effort to draw the line of best fit, so the user can get the optimal results per block’s side. Finally, after the tool runs successfully, a table of primary planning information is shown, such as the area of the building block and its coverage rate. Regardless of the primary stage of the tool’s development, it is a solid base where potential planners with programming skills could invest, so they can make the tool adapt to their individual needs. An example of the entire procedure in a test area is provided, highlighting both the strengths and weaknesses of the final results.Keywords: arcPy, GIS, python, building blocks
Procedia PDF Downloads 179591 Advanced Phosphorus-Containing Polymer Materials towards Eco-Friendly Flame Retardant Epoxy Thermosets
Authors: Ionela-Daniela Carja, Diana Serbezeanu, Tachita Vlad-Bubulac, Corneliu Hamciuc
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Nowadays, epoxy materials are extensively used in ever more areas and under ever more demanding environmental conditions due to their remarkable combination of properties, light weight and ease of processing. However, these materials greatly increase the fire risk due to their flammability and possible release of toxic by-products as a result of their chemical composition which consists mainly from carbon and hydrogen atoms. Therefore, improving the fire retardant behaviour to prevent the loss of life and property is of particular concern among government regulatory bodies, consumers and manufacturers alike. Modification of epoxy resins with organophosphorus compounds, as reactive flame retardants or additives, is the key to achieving non-flammable advanced epoxy materials. Herein, a detailed characterization of fire behaviour for a series of phosphorus-containing epoxy thermosets is reported. A carefully designed phosphorus flame retardant additive was simply blended with a bifunctional bisphenol-A based epoxy resin. Further thermal cross-linking in the presence of various aminic hardeners led to eco-friendly flame retardant epoxy resins. The type of hardener, concentration of flame retardant additive, compatibility between the components of the mixture, char formation and morphology, thermal stability, flame retardant mechanisms were investigated. It was found that even a very low content of phosphorus introduced into the epoxy matrix increased the limiting oxygen index value to about 30%. In addition, the peak of the heat release rate value decreased up to 45% as compared to the one of the neat epoxy system. The main flame retardant mechanism was the condensed-phase one as revealed by SEM and XPS measurements.Keywords: condensed-phase mechanism, eco-friendly phosphorus flame retardant, epoxy resin, thermal stability
Procedia PDF Downloads 312590 Lateral Torsional Buckling Resistance of Trapezoidally Corrugated Web Girders
Authors: Annamária Käferné Rácz, Bence Jáger, Balázs Kövesdi, László Dunai
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Due to the numerous advantages of steel corrugated web girders, its application field is growing for bridges as well as for buildings. The global stability behavior of such girders is significantly larger than those of conventional I-girders with flat web, thus the application of the structural steel material can be significantly reduced. Design codes and specifications do not provide clear and complete rules or recommendations for the determination of the lateral torsional buckling (LTB) resistance of corrugated web girders. Therefore, the authors made a thorough investigation regarding the LTB resistance of the corrugated web girders. Finite element (FE) simulations have been performed to develop new design formulas for the determination of the LTB resistance of trapezoidally corrugated web girders. FE model is developed considering geometrical and material nonlinear analysis using equivalent geometric imperfections (GMNI analysis). The equivalent geometric imperfections involve the initial geometric imperfections and residual stresses coming from rolling, welding and flame cutting. Imperfection sensitivity analysis was performed to determine the necessary magnitudes regarding only the first eigenmodes shape imperfections. By the help of the validated FE model, an extended parametric study is carried out to investigate the LTB resistance for different trapezoidal corrugation profiles. First, the critical moment of a specific girder was calculated by FE model. The critical moments from the FE calculations are compared to the previous analytical calculation proposals. Then, nonlinear analysis was carried out to determine the ultimate resistance. Due to the numerical investigations, new proposals are developed for the determination of the LTB resistance of trapezoidally corrugated web girders through a modification factor on the design method related to the conventional flat web girders.Keywords: corrugated web, lateral torsional buckling, critical moment, FE modeling
Procedia PDF Downloads 283589 Structural Anatomy and Deformation Pattern of the Palghat-Cauvery Shear Zone in the Central Sector, Tamil Nadu, Southern India
Authors: Mrinal Mukherjee, Gargi Seal, Bitopan Mazumdar, Prakhar Agarwal
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The central sector of Palghat-Cauvery Shear zone Tamil Nadu, India, had been studied with reference to development, mode of occurrence, interrelationship and variation of structural elements. The litho assemblages of the study area include gneisses migmatites granites and bear signature of multistage deformation patterns. The early deformation D1 is characterized in migmatites and gneisses by the development of tight to isoclinal, recumbent to reclined folds within the compositional bands that are refolded subsequently to produce D2 deformation structures ranging from type-II to type-III superposed geometry. The granite, in general, is undeformed, save a few places where strong mylonitic foliation developed with stretching lineation on it. The D1-D2 structures of gneisses and migmatites were affected by a D3 stage- E-W trending shear zone (Palghat-Cauvery Shear zone) that dips steeply towards north. The shear zone is characterized by the development of mylonite zone with stretching lineation on foliation, shear band structures, modification of geometry and orientation of earlier folds and foliations within the shear zone and development of shear induced folds and foliations. Several anastomosing lenses of shear zones define the larger Palghat-Cauvery Shear zone. The orientation of the shear induced folds and foliations and deflections of earlier foliation and folds within the Palghat-Cauvery shear zone indicate an oblique-slip thrust-shear with north-towards-east sense of displacement. The E-W trending shear zone is further openly folded along N-S in the D4 stage of deformation.Keywords: deformation, migmatites, mylonites, shear zones
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