Search results for: anti corrosion
2352 Reinforced Concrete, Problems and Solutions: A Literature Review
Authors: Omar Alhamad, Waleed Eid
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Reinforced concrete is a concrete lined with steel so that the materials work together in the resistance forces. Reinforcement rods or mesh are used for tensile, shear, and sometimes intense pressure in a concrete structure. Reinforced concrete is subject to many natural problems or industrial errors. The result of these problems is that it reduces the efficiency of the reinforced concrete or its usefulness. Some of these problems are cracks, earthquakes, high temperatures or fires, as well as corrosion of reinforced iron inside reinforced concrete. There are also factors of ancient buildings or monuments that require some techniques to preserve them. This research presents some general information about reinforced concrete, the pros and cons of reinforced concrete, and then presents a series of literary studies of some of the late published researches on the subject of reinforced concrete and how to preserve it, propose solutions or treatments for the treatment of reinforced concrete problems, raise efficiency and quality for a longer period. These studies have provided advanced and modern methods and techniques in the field of reinforced concrete.Keywords: reinforced concrete, treatment, concrete, corrosion, seismic, cracks
Procedia PDF Downloads 1522351 Development and Characterization of a Fluorinated-Ethylene-Propylene (FEP) Polymer Coating on Brass Faucets
Authors: S. Zouari, H. Ghorbel, H. Liao, R. Elleuch
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Research is increasingly moving towards the use of surface treatment processes to limit environmental effects. Electrolytic plating has traditionally been seen as a way to protect brass products, especially faucets, from mechanical and chemical damage. However, this method was not effective industrially, economically and ecologically. The aim of this work is to develop non-usual polymer coatings for brass faucets in order to improve the performance of brass and to replace electrolytic chromium coatings, thereby reducing environmental impact. Fluorinated-Ethylene-Propylene polymer (FEP) was chosen for its excellent mechanical and chemical properties and its good environmental performance. This coating was developed by spraying (painting) process onto brass substrates. The coatings obtained were characterized using a scanning electron microscope to evaluate the morphology of the deposits and their porosity rate. Grid adhesion, surface energy and corrosion tests (salt spray) were also performed to evaluate the mechanical and chemical behavior of these coatings properly. The results show that the deposits obtained have a homogeneous microstructure with a very low porosity rate. The results of the grid adhesion test prove the conformity of the test according to the NF077 standard. The coatings have a hydrophobic character following the low values of surface energy obtained and a very good resistance to corrosion. These results are interesting and may represent real technological issues in the industrial field.Keywords: FEP coatings, spraying process, brass, adhesion, surface energy, corrosion resistance
Procedia PDF Downloads 1412350 Development of Hydrophobic Coatings on Aluminum Alloy 7075
Authors: Nauman A. Siddiqui
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High performance requirement of aircrafts and marines industry demands to cater major industrial problems like wetting, high-speed efficiency, and corrosion resistance. These problems can be resolved by producing the hydrophobic surfaces on the metal substrate. By anodization process, the surface of AA 7075 has been modified and achieved a rough surface with a porous aluminum oxide (Al2O3) structure at nano-level. This surface modification process reduces the surface contact energy and increases the liquid contact angle which ultimately enhances the anti-icing properties. Later the Silane and Polyurethane (PU) coatings on the anodized surface have produced a contact angle of 130°. The results showed a good water repellency and self-cleaning properties. Using SEM analysis, micrographs revealed the round nano-porous oxide structure on the substrate. Therefore this technique can help in increasing the speed efficiency by reducing the friction with the outer interaction and can also be declared as a green technique since it is user-friendly.Keywords: AA 7075, hydrophobicity, silanes, polyurethane, anodization
Procedia PDF Downloads 2772349 Fe-BTC Based Electrochemical Sensor for Anti-Psychotic and Anti-Migraine Drugs: Aripiprazole and Rizatriptan
Authors: Sachin Saxena, Manju Srivastava
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The present study describes a stable, highly sensitive and selective analytical sensor. Fe-BTC was synthesized at room temperature using the noble Iron-trimesate system. The high surface area of as synthesized Fe-BTC proved MOFs as ideal modifiers for glassy carbon electrode. The characterization techniques such as TGA, XRD, FT-IR, BET (BET surface area= 1125 m2/gm) analysis explained the electrocatalytic behaviour of Fe-BTC towards these two drugs. The material formed is cost effective and exhibit higher catalytic behaviour towards analyte systems. The synergism between synthesized Fe-BTC and electroanalytical techniques helped in developing a highly sensitive analytical method for studying the redox fate of ARP and RZ, respectively. Cyclic voltammetry of ferricyanide system proved Fe-BTC/GCE with an increase in 132% enhancement in peak current value as compared to that of GCE. The response characteristics of cyclic voltammetry (CV) and square wave voltammetry (SWV) revealed that the ARP and RZ could be effectively accumulated at Fe-BTC/GCE. On the basis of the electrochemical measurements, electrode dynamics parameters have been evaluated. Present study opens up new field of applications of MOFs modified GCE for drug sensing.Keywords: MOFs, anti-psychotic, electrochemical sensor, anti-migraine drugs
Procedia PDF Downloads 1662348 The Association of IL-17 Serum Levels with Disease Severity and Onset of Symptoms in Rheumatoid Arthritis Patients
Authors: Fatemeh Keshavarz
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Background: Rheumatoid arthritis (RA) is one of the most common autoimmune diseases, often leading to joint damage and physical disability. This study aimed to investigate the relationship of serum levels of interleukin 17 and anti-CCP factor with disease severity in RA patients. Materials and Methods: Fifty-four patients with RA confirmed by clinical and laboratory criteria were recruited. A 5 ml venous blood sample was taken from every patient, its serum was separated. Based on clinical data and severity of symptoms, patients were classified into three groups of those with mild, moderate, and severe symptoms. Serum levels of IL-17 and anti-CCP in all samples were measured using ELISA. Results: Analysis of IL-17 serum levels in different groups showed that its amount was higher in the group with mild clinical symptoms than in other groups. Comparison of IL-17 serum levels between mild and moderate disease severity groups showed a statistically significant relationship. There was also a positive linear relationship between anti-CCP and serum IL-17 levels in different groups of the disease, and serum IL-17 levels were inversely related to the duration of exposure to the disease. Conclusion: Higher IL-17 serum levels in patients with mild symptom severity confirm that this highly specific marker is involved in the pathogenesis of RA and may be effective in initiating patients’ clinical symptoms.Keywords: IL-17, anti-CCP, rheumatoid arthritis, autoimmune
Procedia PDF Downloads 1392347 Electrochemical Studies of Si, Si-Ge- and Ge-Air Batteries
Authors: R. C. Sharma, Rishabh Bansal, Prajwal Menon, Manoj K. Sharma
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Silicon-air battery is highly promising for electric vehicles due to its high theoretical energy density (8470 Whkg⁻¹) and its discharge products are non-toxic. For the first time, pure silicon and germanium powders are used as anode material. Nickel wire meshes embedded with charcoal and manganese dioxide powder as cathode and concentrated potassium hydroxide is used as electrolyte. Voltage-time curves have been presented in this study for pure silicon and germanium powder and 5% and 10% germanium with silicon powder. Silicon powder cell assembly gives a stable voltage of 0.88 V for ~20 minutes while Si-Ge provides cell voltage of 0.80-0.76 V for ~10-12 minutes, and pure germanium cell provides cell voltage 0.80-0.76 V for ~30 minutes. The cell voltage is higher for concentrated (10%) sodium hydroxide solution (1.08 V) and it is stable for ~40 minutes. A sharp decrease in cell voltage beyond 40 min may be due to rapid corrosion.Keywords: Silicon-air battery, Germanium-air battery, voltage-time curve, open circuit voltage, Anodic corrosion
Procedia PDF Downloads 2382346 Chemical and Biological Examination of De-Oiled Indian Propolis
Authors: Harshada Vaidya-Kannur, Dattatraya Naik
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Propolis, one of the beehive products also referred as bee-glue is sticky dark coloured complex mixture of compounds. The volatile oil can be isolated from the propolis by hydrodistillation. The mark that is left behind after the removal of volatile oil is referred as the de-oiled propolis. Antioxidant as well as anti-inflammatory properties of total ethanolic extract of de-oiled propolis (TEEDP) was investigated. Another lot of deoiled propolis was successively exacted with hexane, ethyl acetate and ethanol. Activities of these fractions were also determined. Antioxidant activity was determined by studying ABTS, DPPH and NO radical scavenging. Determination of anti-inflammatory activity was carried out by topical TPA induced mouse ear oedema model. It is noteworthy that ethyl acetate fraction of deoiled propolis (EAFDP) exhibited 49.45 % TEAC activity at the concentration 0.2 mg/ml which is equivalent to the activity of trolox at the concentration 0.2 mg/ml. Its DPPH scavenging activity (72.56%) was closely comparable to that of trolox (75%). However its NO scavenging activity was comparatively low. From IC50 values it could be concluded that the efficiency of scavenging ABTS radicals by the de-oiled propolis was more pronounced as compared to scavenging of other radicals. Studies by TPA induced mouse ear inflammation model indicated that the de-oiled propolis of Indian origin had significant topical anti-inflammatory activity. The EAFDP was found to be the most active fraction for this activity also. The purification of EAFP yielded six pure crystalline compounds. These compounds were identified by their physical data and spectral data.Keywords: anti-inflammatory activity, anti-oxidant activity, column chromatography, de-oiled propolis
Procedia PDF Downloads 2882345 Sinapic Acid Attenuation of Cyclophosphamide-Induced Liver Toxicity in Mice by Modulating Oxidative Stress, Nf-κB, and Caspase-3
Authors: Shiva Rezaei, Seyed Jalal Hosseinimehr, Abbasali Karimpour Malekshah, Mansooreh Mirzaei, Fereshteh Talebpour Amiri, Mehryar Zargari
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Objective(s): Cyclophosphamide (CP), as an antineoplastic drug, is widely used in cancer patients, and liver toxicity is one of its complications. Sinapic acid (SA), as a natural phenylpropanoid, has antioxidant, anti-inflammatory, and anti-cancer properties. Materials and Methods: The purpose of the current study was to determine the protective effect of SA versus CP-induced liver toxicity. In this research, BALB/c mice were treated with SA (5 and 10 mg/kg) orally for one week, and CP (200 mg/kg) was injected on day 3 of the study. Oxidative stress markers, serum liver-specific enzymes, histopathological features, caspase-3, and nuclear factor kappa-B cells were then checked. Results: CP induced hepatotoxicity in mice and showed structural changes in liver tissue. CP significantly increased liver enzymes and lipid peroxidation and decreased glutathione. The immunoreactivity of caspase-3 and nuclear factor kappa-B cells was significantly increased. Administration of SA significantly maintained histochemical parameters and liver function enzymes in mice treated with CP. Immunohistochemical examination showed SA reduced apoptosis and inflammation. Conclusion: The data confirmed that SA with anti-apoptotic, anti-oxidative, and anti-inflammatory activities was able to preserve CP-induced liver injury in mice.Keywords: apoptosis, cyclophosphamide, liver injury, inflammation, oxidative stress, sinapic acid
Procedia PDF Downloads 562344 Anti-Site Disorder Effects on the Magnetic Properties of Sm₂NiMnO₆ Thin Films
Authors: Geetanjali Singh, R. J. Choudhary, Anjana Dogra
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Here we report the effects of anti-site disorder, present in the sample, on the magnetic properties of Sm₂NiMnO₆ (SNMO) thin films. To our best knowledge, there are no studies available on the thin films of SNMO. Thin films were grown using pulsed laser deposition technique on SrTiO₃ (STO) substrate under oxygen pressure of 800 mTorr. X-ray diffraction (XRD) profiles show that the film grown is epitaxial. Field cooled (FC) and zero field cooled (ZFC) magnetization curve increase as we decrease the temperature till ~135K. A broad dip was observed in both the curves below this temperature which is more dominating in ZFC curve. An additional sharp cusplike shape was observed at low temperature (~20 K) which is due to the re-entrant spin-glass like properties present in the sample. Super-exchange interaction between Ni²⁺-O-Mn⁴⁺ is attributed to the FM ordering in these samples. The spin-glass feature is due to anti-site disorder within the homogeneous sample which was stated to be due to the mixed valence states Ni³⁺ and Mn³⁺ present in the sample. Anti-site disorder was found to play very crucial role in different magnetic phases of the sample.Keywords: double perovskite, pulsed laser deposition, spin-glass, magnetization
Procedia PDF Downloads 2622343 Synthesis of New Anti-Tuberculosis Drugs
Authors: M. S. Deshpande, Snehal D. Bomble
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Tuberculosis (TB) is a deadly contagious disease that is caused by a bacterium called Mycobacterium tuberculosis. More than sixty years ago, the introduction of the first anti-TB drugs for the treatment of TB (streptomycin (STR), p-aminosalcylic acid (PAS), isoniazid (INH), and then later ethambutol (EMB) and rifampicin (RIF)) gave optimism to the medical community, and it was believed that the disease would be completely eradicated soon. Worldwide, the number of TB cases has continued to increase, but the incidence rate has decreased since 2003. Recently, highly drug-resistant forms of TB have emerged worldwide. The prolonged use of classical drugs developed a growing resistance and these drugs have gradually become less effective and incapable to meet the challenges, especially those of multi drug resistant (MDR)-TB, extensively drug resistant (XDR)-TB, and HIV-TB co-infections. There is an unmet medical need to discover newer synthetic molecules and new generation of potent drugs for the treatment of tuberculosis which will shorten the time of treatment, be potent and safe while effective facing resistant strains and non-replicative, latent forms, reduce adverse side effect and not interfere in the antiretroviral therapy. This paper attempts to bring out the review of anti-TB drugs, and presents a novel method of synthesizing new anti-tuberculosis drugs and potential compounds to overcome the bacterial resistance and combat the re-emergence of tuberculosis.Keywords: tuberculosis, mycobacterium, multi-drug resistant (MDR)-TB, extensively drug resistant (XDR)-TB
Procedia PDF Downloads 3802342 Antioxidant and Anti-Inflammatory Activities of Bioactive Compounds Derived from Thunbergia laurifolia Aqueous Leave Extract
Authors: Marasri Junsi, Sunisa Siripongvutikorn, Chutha Takahashi Yupanqui, Worrapong Usawakesmanee
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Thunbergia laurifolia has been used for folklore medicine purposes and consumed in the form of herbal tea in Thailand since ancient times. To evaluate the bioactive compounds of aqueous leave extract possessed antioxidant and anti-inflammatory activities. The antioxidant activities were examined by total extractable phenolic content (TPC), total extractable flavonoid content (TFC), ABTS radical scavenging, DPPH radical scavenging, FRAP reducing antioxidant power expressed as mg of gallic acid trolox and caffeic acid for the equivalents. Results indicated that the extract had high TPC and antioxidant activities. In addition, the HPLC-DAD analysis of phenolics and flavonoids indicated the presence of caffeic acid and rutin as bioactive compounds. Exposure of cells with the extract using nitric oxide (NO) production in RAW 264.7 murine macrophage cell line induced by lipopolysaccharide (LPS) was significantly reduced NO production and increased cell proliferation. The obtained results demonstrated that the extract contains a high potential to be used as anti-inflammatory and antioxidant substances.Keywords: Thunbergia laurifolia, anti-inflammatory, antioxidant activities, RAW264.7
Procedia PDF Downloads 3112341 Large Strain Compression-Tension Behavior of AZ31B Rolled Sheet in the Rolling Direction
Authors: A. Yazdanmehr, H. Jahed
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Being made with the lightest commercially available industrial metal, Magnesium (Mg) alloys are of interest for light-weighting. Expanding their application to different material processing methods requires Mg properties at large strains. Several room-temperature processes such as shot and laser peening and hole cold expansion need compressive large strain data. Two methods have been proposed in the literature to obtain the stress-strain curve at high strains: 1) anti-buckling guides and 2) small cubic samples. In this paper, an anti-buckling fixture is used with the help of digital image correlation (DIC) to obtain the compression-tension (C-T) of AZ31B-H24 rolled sheet at large strain values of up to 10.5%. The effect of the anti-bucking fixture on stress-strain curves is evaluated experimentally by comparing the results with those of the compression tests of cubic samples. For testing cubic samples, a new fixture has been designed to increase the accuracy of testing cubic samples with DIC strain measurements. Results show a negligible effect of anti-buckling on stress-strain curves, specifically at high strain values.Keywords: large strain, compression-tension, loading-unloading, Mg alloys
Procedia PDF Downloads 2382340 The Investigation of Cracking on the Shell of Dryers (tag No. 2DR-1745 and DR-1402) in Shahid Tondguyan Petrochemical Company (STPC)
Authors: Ali Haghiri
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This research has been to investigate the cause of the stress corrosion cracking on dryer equipment (2DR-1745 and DR-1402) in Shahid Tondguyan Petrochemical Company (STPC). These dryers are as a drying powder Terphetalic acid in CTA2 and CTA1 unit. After passing through RVF equipment, wet cake moisture content of about 14% and temperature of 90C changed into a dry cake with a moisture content of less than 0.1% and the final temperature of about 140C and sent out Final Silo (FS-1820). After the declaration of the operation department concerning the observation of acid leakage under the primary insulation was decided that at the first opportunity, this issue must be investigated. So, after the shutdown of a unit at the date 2012/10/20 (2DR-1745) and 2021/11/24 (DR-1402) and after washing the dryer wall, insulation around the wall opened and it was found to crack and leakage from some points.Keywords: stress corrosion cracking, residual stress, austenitic stainless steel, Br- ion
Procedia PDF Downloads 1612339 Study of Anti-Symmetric Flexural Mode Propagation along Wedge Tip with a Crack
Authors: Manikanta Prasad Banda, Che Hua Yang
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Anti-symmetric wave propagation along the particle motion of the wedge waves is known as anti-symmetric flexural (ASF) modes which travel along the wedge tips of the mid-plane apex with a small truncation. This paper investigates the characteristics of the ASF modes propagation with the wedge tip crack. The simulation and experimental results obtained by a three-dimensional (3-D) finite element model explained the contact acoustic non-linear (CAN) behavior in explicit dynamics in ABAQUS and the ultrasonic non-destructive testing (NDT) method is used for defect detection. The effect of various parameters on its high and low-level conversion modes are known for complex reflections and transmissions involved with direct reflections and transmissions. The results are used to predict the location of crack through complex transmission and reflection coefficients.Keywords: ASF mode, crack detection, finite elements method, laser ultrasound technique, wedge waves
Procedia PDF Downloads 1362338 Study the Effect of Sensitization on the Microstructure and Mechanical Properties of Gas Tungsten Arc Welded AISI 304 Stainless Steel Joints
Authors: Viranshu Kumar, Hitesh Arora, Pradeep Joshi
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SS 304 is Austenitic stainless steel with Chromium and Nickel as basic constituents. It has excellent corrosion resistance properties and very good weldability. Austenitic stainless steels have superior mechanical properties at high temperatures and are used extensively in a range of applications. SS 304L has wide applications in various industries viz. Nuclear, Pharmaceutical, marine, chemical etc. due to its excellent applications and ease of joining this material has become very popular for fabrication as well as weld surfacing. Austenitic stainless steels have a tendency to form chromium depleted zones at the grain boundaries during welding and heat treatment, where chromium combines with available carbon in the vicinity of the grain boundaries, to produce an area depleted in chromium, and thus becomes susceptible to intergranular corrosion. This phenomenon is known as sensitization.Keywords: sensitization, SS 304, GTAW, mechanical properties, carbideprecipitationHAZ, microstructure, micro hardness, tensile strength
Procedia PDF Downloads 3982337 Experimental Study of Mechanical and Durability Properties of HPC Made with Binary Blends of Cement
Authors: Vatsal Patel, Niraj Shah
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The aim of the research reported in this paper is to assess the Strength and durability performance of High Performance Concrete containing different percentages of waste marble powder produced from marble industry. Concrete mixes possessing a target mean compressive strength of 70MPa were prepared with 0%,5%,10%,15% and 20% cement replacement by waste marble powder with W/B =0.33. More specifically, the compressive strength, flexural strength, chloride penetration, sorptivity and accelerated corrosion were determined. Concrete containing 10% waste marble powder proved to have best Mechanical and durability properties than other mixtures made with binary blends. However, poorer performance was noticeable when replacement percentage was higher. The replacement of Waste Marble Powder will have major environmental benefits.Keywords: durability, high performance concrete, marble waste powder, sorptivity, accelerated corrosion
Procedia PDF Downloads 3452336 Effect of Environmental Stress Factors on the Degradation of Display Glass
Authors: Jinyoung Choi, Hyun-A Kim, Sunmook Lee
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The effects of environmental stress factors such as storage conditions on the deterioration phenomenon and the characteristic of the display glass were studied. In order to investigate the effect of chemical stress on the glass during the period of storage, the respective components of commercial glass were first identified by XRF (X-ray fluorescence). The glass was exposed in the acid, alkali, neutral environment for about one month. Thin film formed on the glass surface was analyzed by XRD (X-ray diffraction) and FT-IR (Fourier transform infrared). The degree of corrosion and the rate of deterioration of each sample were confirmed by measuring the concentrations of silicon, calcium and chromium with ICP-OES (Inductively coupled plasma-optical emission spectrometry). The optical properties of the glass surface were confirmed by SEM (Scanning electron microscope) before and after the treatment. Acknowledgement—The authors gratefully acknowledge the financial support from the Ministry of Trade, Industry and Energy (Grant Number: 10076817)Keywords: corrosion, degradation test, display glass, environmental stress factor
Procedia PDF Downloads 4602335 The Effect of H2S on Crystal Structure
Authors: C. Venkataraman B. E., J. Nagarajan B. E., V. Srinivasan M. Tech
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For a better understanding on sulfide stress corrosion cracking, a theoretical approach based on crystal structure, molecule behavior, flow of electrons and electrochemical reaction is developed. Its impact on different materials such as carbon steel, low alloy, alloy for sour (H2S) environments is studied. This paper describes the theories on various disaster and failures occurred in the industry by Stress Corrosion Cracking (SCC). Parameters such as pH of process fluid, partial pressure of CO2, O2, Chlorine, effect of internal pressure (crystal structure deformation by stress), and external environment condition are considered. An analytical line graph is then created for process fluid parameter verses time, temperature, induced/residual stress due to local pressure build-up. By comparison with the load test result of NACE and ASTM, it is possible to predict and simplify the control of SCC by use of materials like ferritic, Austenitic material in the oil and gas & petroleum industries.Keywords: crystal structure deformation, failure assessment, alloy-environment combination, H2S
Procedia PDF Downloads 4012334 Ion Beam Sputtering Deposition of Inorganic-Fluoropolymer Nano-Coatings for Real-Life Applications
Authors: M. Valentini, D. Melisi, M. A. Nitti, R A. Picca, M. C. Sportelli, E. Bonerba, G. Casamassima, N. Cioffi, L. Sabbatini, G. Tantillo, A. Valentini
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In recent years antimicrobial coatings are receiving increasing attention due to their high demand in medical applications as well as in healthcare and hygiene. Research and technology are constantly involved to develop advanced finishing which can provide bacteriostatic growth without compromising the other typical properties of a textile as durability and non-toxicity, just to cite a few. Here we report on the antimicrobial coatings obtained, at room temperature and without the use of solvents, by means of the ion beam co-sputtering technique of an Ag target and a polytetrafluoroethylene one. In particular, such method allows to conjugate the well-known antimicrobial action of silver with the anti-stain and water-repellent properties of the fluoropolymer. Moreover, different Ag nanoparticle loadings (φ) were prepared by tuning the material deposition conditions achieving a fine control on film thickness and their antimicrobial/anti-stain properties.Keywords: antimicrobial, ion beam sputtering, nanocoatings, anti-stain
Procedia PDF Downloads 3922333 Improving Biodegradation Behavior of Fabricated WE43 Magnesium Alloy by High-Temperature Oxidation
Authors: Jinge Liu, Shuyuan Min, Bingchuan Liu, Bangzhao Yin, Bo Peng, Peng Wen, Yun Tian
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WE43 magnesium alloy can be additively manufactured via laser powder bed fusion (LPBF) for biodegradable applications, but the as-built WE43 exhibits an excessively rapid corrosion rate. High-temperature oxidation (HTO) was performed on the as-built WE43 to improve its biodegradation behavior. A sandwich structure including an oxide layer at the surface, a transition layer in the middle, and the matrix was generated influenced by the oxidation reaction and diffusion of RE atoms when heated at 525 ℃for 8 hours. The oxide layer consisted of Y₂O₃ and Nd₂O₃ oxides with a thickness of 2-3 μm. The transition layer is composed of α-Mg and Y₂O₃ with a thickness of 60-70 μm, while Mg24RE5 could be observed except α-Mg and Y₂O₃. The oxide layer and transition layer appeared to have an effective passivation effect. The as-built WE43 lost 40% weight after the in vitro immersion test for three days and finally broke into debris after seven days of immersion. The high-temperature oxidation samples kept the structural integrity and lost only 6.88 % weight after 28-day immersion. The corrosion rate of HTO samples was significantly controlled, which improved the biocompatibility of the as-built WE43 at the same time. The samples after HTO had better osteogenic capability according to ALP activity. Moreover, as built WE43 performed unqualified in cell adhesion and hemolytic test due to its excessively rapid corrosion rate. While as for HTO samples, cells adhered well, and the hemolysis ratio was only 1.59%.Keywords: laser powder bed fusion, biodegradable metal, high temperature oxidation, biodegradation behavior, WE43
Procedia PDF Downloads 1052332 Investigating Prostaglandin E2 and Intracellular Oxidative Stress Levels in Lipopolysaccharide-Stimulated RAW 264.7 Macrophages upon Treatment with Strobilanthes crispus
Authors: Anna Pick Kiong Ling, Jia May Chin, Rhun Yian Koh, Ying Pei Wong
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Background: Uncontrolled inflammation may cause serious inflammatory diseases if left untreated. Non-steroidal anti-inflammatory drug (NSAIDs) is commonly used to inhibit pro-inflammatory enzymes, thus, reduce inflammation. However, long term administration of NSAIDs leads to various complications. Medicinal plants are getting more attention as it is believed to be more compatible with human body. One of them is a flavonoid-containing medicinal plants, Strobilanthes crispus which has been traditionally claimed to possess anti-inflammatory and antioxidant activities. Nevertheless, its anti-inflammatory activities are yet to be scientifically documented. Objectives: This study aimed to examine the anti-inflammatory activity of S. crispus by investigating its effects on intracellular oxidative stress and prostaglandin E2 (PGE2) levels. Materials and Methods: In this study, the Maximum Non-toxic Dose (MNTD) of methanol extract of both leaves and stems of S. crispus was first determined using 3-(4,5-dimethylthiazolyl-2)-2,5-diphenytetrazolium Bromide (MTT) assay. The effects of S. crispus extracts at MNTD and half MNTD (½MNTD) on intracellular ROS as well as PGE2 levels in 1.0 µg/mL LPS-stimulated RAW 264.7 macrophages were then be measured using DCFH-DA and a competitive enzyme immunoassay kit, respectively. Results: The MNTD of leaf extract was determined as 700µg/mL while for stem was as low as 1.4µg/mL. When LPS-stimulated RAW 264.7 macrophages were subjected to the MNTD of S. crispus leaf extract, both intracellular ROS and PGE2 levels were significantly reduced. In contrast, stem extract at both MNTD and ½MNTD did not significantly reduce the PGE2 level, but significantly increased the intracellular ROS level. Conclusion: The methanol leaf extract of S. crispus may possess anti-inflammatory properties as it is able to significantly reduce the intracellular ROS and PGE2 levels of LPS-stimulated cells. Nevertheless, further studies such as investigating the interleukin, nitric oxide and cytokine tumor necrosis factor-α (TNFα) levels has to be conducted to further confirm the anti-inflammatory properties of S. crispus.Keywords: anti-inflammatory, natural products, prostaglandin E2, reactive oxygen species
Procedia PDF Downloads 2842331 Production and Characterization of Implant Material Produced by Using Electroless Ni Plated Al2O3-Co-Cr-Ti Powders
Authors: Ahmet Yonetken, Ayhan Erol
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The microstructure, mechanical properties and corrosion characteristics of Ni plated %10Al2O3-%40Co-%20Cr and %10Ti powders were investigated using specimens produced by tube furnace sintering at 800-1200°C temperature. A uniform nickel layer on Al2O3-Co-Cr and Ti powders was deposited prior to sintering using electroless plating technique. A composite consisting of quintet additions, a metallic phase, Ti,Cr and Co including a ceramic phase, alumina, within a matrix of Ni has been prepared under Ar shroud and then tube furnace sintered. XRD, SEM (Scanning Electron Microscope), corrosion behavior in acidic media were investigated to characterize the properties of the specimens. Experimental results carried out for composition (%10Al2O3-%40Co-%20Cr- %10Ti)20Ni at 1200°C suggest that the best properties as 312.18HV were obtained at 1200°C.Keywords: sintering, intermetallic, Electroless nickel plating, composite
Procedia PDF Downloads 5742330 Generative Adversarial Network Based Fingerprint Anti-Spoofing Limitations
Authors: Yehjune Heo
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Fingerprint Anti-Spoofing approaches have been actively developed and applied in real-world applications. One of the main problems for Fingerprint Anti-Spoofing is not robust to unseen samples, especially in real-world scenarios. A possible solution will be to generate artificial, but realistic fingerprint samples and use them for training in order to achieve good generalization. This paper contains experimental and comparative results with currently popular GAN based methods and uses realistic synthesis of fingerprints in training in order to increase the performance. Among various GAN models, the most popular StyleGAN is used for the experiments. The CNN models were first trained with the dataset that did not contain generated fake images and the accuracy along with the mean average error rate were recorded. Then, the fake generated images (fake images of live fingerprints and fake images of spoof fingerprints) were each combined with the original images (real images of live fingerprints and real images of spoof fingerprints), and various CNN models were trained. The best performances for each CNN model, trained with the dataset of generated fake images and each time the accuracy and the mean average error rate, were recorded. We observe that current GAN based approaches need significant improvements for the Anti-Spoofing performance, although the overall quality of the synthesized fingerprints seems to be reasonable. We include the analysis of this performance degradation, especially with a small number of samples. In addition, we suggest several approaches towards improved generalization with a small number of samples, by focusing on what GAN based approaches should learn and should not learn.Keywords: anti-spoofing, CNN, fingerprint recognition, GAN
Procedia PDF Downloads 1842329 pH and Thermo-Sensitive Nanogels for Anti-Cancer Therapy
Authors: V. Naga Sravan Kumar Varma, H. G. Shivakumar
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The aim of the study was to develop dual sensitive poly (N-isopropylacrylamide-co-acrylic acid) (PNA) nanogels(NGs) and studying its applications for Anti-Cancer therapy. NGs were fabricated by free radical polymerization using different amount of N-isopropylacrylamide and acrylic acid. A study for polymer composition over the effect on LCST in different pH was evaluated by measuring the absorbance at 500nm using UV spectrophotometer. Further selected NG’s were evaluated for change in hydrodynamic diameters in response to pH and temperature. NGs which could sharply respond to low pH value of cancer cells at body temperature were loaded with Fluorouracil (5-FU) using equilibrium swelling method and studied for drug release behaviour in different pH. A significant influence of NGs polymer composition over pH dependent LCST was observed. NGs which were spherical with an average particle size of 268nm at room temperature, shrinked forming an irregular shape when heated above to their respective LCST. 5FU loaded NGs did not intervene any difference in pH depended LCST behaviour of NGs. The in vitro drug release of NGs exhibited a pH and thermo-dependent control release. The cytoxicity study of blank carrier to MCF7 cell line showed no cytotoxicity. The results indicated that PNA NGs could be used as a potential drug carrier for anti-cancer therapy.Keywords: pH and thermo-sensitive, nanogels, P(NIPAM-co-AAc), anti-cancer, 5-FU
Procedia PDF Downloads 3512328 Chemical Composition and Biological Properties of Algerian Honeys
Authors: Ouchemoukh Salim, Amessis-Ouchemoukh Nadia, Guenaoui Nawel, Moumeni Lynda, Zaidi Hicham, Otmani Amar, Sadou Dyhia
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Honey is a hive food rich in carbohydrates and water and it also has a lot of nutrients (enzymes, minerals, organic acids, phytochemicals...). It is used in different nutritional and therapeutic fields. Algerian honey was studied for its physicochemical parameters, nutritional values (moisture, brix, pH, electrical conductivity, and amounts of HMF, proteins, proline, total phenolic compounds and flavonoids) and some biological activities (antioxidant, anti-inflammatory and enzymatic anti-browning). The antioxidant activities of the samples were estimated using different methods (ABTS, DPPH free radicals scavenging, reducing power, and chelating ferrous activity). All honeys were acidic (3.45≤pH≤4.65). The color varied from mimosa yellow to dark brown. The specific rotation was levorotatory in most honey samples, and the electrical conductivity, hydroxymethylfurfural, and proline values agreed with the international honey requirements. For anti-inflammatory activity, the results showed that the inhibiting capacity of the denaturation of the BSA of the honey analyzed varied from 15 to 75 % with a maximum of activity at the concentration of 0,5 mg/ml. All honey exhibited enzymatic anti-browning on different slices of fruits. In fact, the results showed that the controls have the greatest browning unit compared to the honeys studied and PPO and POD enzymes had the lowest enzyme activity. High significant correlations were found between the color of honey, its antioxidant content and its biological activities (antioxidant, anti-inflammatory and enzymatic anti-browning). The dark color of honey is a good indicator of the best biological properties, therefore, the best nutritional and therapeutic values.Keywords: honey, physico-chemical parameters, bioactive compounds, biological properties
Procedia PDF Downloads 552327 Potential Drug-Drug Interactions at a Referral Hematology-Oncology Ward in Iran: A Cross-Sectional Study
Authors: Sara Ataei, Molouk Hadjibabaie, Shirinsadat Badri, Amirhossein Moslehi, Iman Karimzadeh, Ardeshir Ghavamzadeh
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Purpose: To assess the pattern and probable risk factors for moderate and major drug–drug interactions in a referral hematology-oncology ward in Iran. Methods: All patients admitted to hematology–oncology ward of Dr. Shariati Hospital during a 6-month period and received at least two anti-cancer or non-anti-cancer medications simultaneously were included. All being scheduled anti-cancer and non-anti-cancer medications both prescribed and administered during ward stay were considered for drug–drug interaction screening by Lexi-Interact On- Desktop software. Results: One hundred and eighty-five drug–drug interactions with moderate or major severity were detected from 83 patients. Most of drug–drug interactions (69.73 %) were classified as pharmacokinetics. Fluconazole (25.95 %) was the most commonly offending medication in drug–drug interactions. Interaction of sulfamethoxazole-trimethoprim with fluconazole was the most common drug–drug interaction (27.27 %). Vincristine with imatinib was the only identified interaction between two anti-cancer agents. The number of administered medications during ward stay was considered as an independent risk factor for developing a drug–drug interaction. Conclusions: Potential moderate or major drug–drug interactions occur frequently in patients with hematological malignancies or related diseases. Performing larger standard studies are required to assess the real clinical and economical effects of drug–drug interactions on patients with hematological and non-hematological malignancies.Keywords: drug–drug interactions, hematology–oncology ward, hematological malignancies
Procedia PDF Downloads 4542326 Evaluation of the Standard Practice of Availability of Anti-Tuberculosis Drugs in Community Pharmacies
Authors: Udaykumar R., M. S. Ganachari
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In order to engage community pharmacies in Tuberculosis care, a survey has been conducted in Belgaum city, Karnataka state, India. After the survey divided into two groups one is control group and another one is intervention group. One is dispensing of anti-tuberculosis drugs, and another one is non-availability of anti-tuberculosis drugs. Those community pharmacists who are voluntarily interesting for becoming DOTS (Directly observed treatment short course) provider and RNTCP (Revised national tuberculosis control programme) objectives. Structured training is conducted for community pharmacist who are dispensing anti-tuberculosis drugs. The training module includes record maintaining, reporting to the RNTCP, Medication adherence etc. In case of non-availability of anti-tuberculosis drugs, the district RNTCP has been given training for community pharmacist by providing free of drugs to the community pharmacies. So, community pharmacies can dispense anti-tuberculosis drugs to the patients. The target of this study is Private community pharmacies. A simple random sampling method is used and 550 private community pharmacy shops has been involved in Belgaum city of Karnataka state, India. Significance of the Study: This study mainly focused on training of DOTS (Directly observed treatment short course) to the private community pharmacist. Indian Govt. Considers Private Providers as Assets for TB Control and Care to Achieve National Strategic Plan for TB Elimination 2017-2025. The Govt. has not fully tapped the Potential of Private Pharmacies to Fight TB. Providing DOTS as per patient’s convenience through community DOT Providers with periodic monitoring may reduce the treatment Default. We explore RNTCP objectives interventions that can have directly managed by private community pharmacy shop. Objectives: Survey of anti-tuberculosis drugs in Community pharmacy shop in Belgaum city. Interested community pharmacist who are willing to become DOTS (Directly observed treatment short course) Provider. Major Findings:Most of the community pharmacist are dispensing anti-tuberculosis drugs without having knowledge of DOTS therapy and RNTCP objectives. No community pharmacist is aware of RNTCP and Tuberculosis burden in India. Most of the Pharmacist agreed to come for RNTCP Training module for the community pharmacist. Some of the community pharmacist not dispensing anti-tuberculosis drugs and they agreed to become official DOTS provider. Concluding Statement: Awareness of role of community pharmacist on tuberculosis control and care has been neglected. More than 50% of tuberculosis patients seeking treatments from privatesector. In this study finds the major gap between government and private sector on tuberculosis treatment.Keywords: community pharmacist, directly observed treatment short course(DOTS), revised national tuberculosis control programme (RNTCP), private pharmacies, anti-tuberculosis drugs
Procedia PDF Downloads 1242325 In Silico Study of the Biological and Pharmacological Activity of Nigella sativa
Authors: Ammar Ouahab, Meriem Houichi , Sanna Mihoubi
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Background: Nigella sativa is an annual flowering plant, belongs to the Ranunculaceae family. It has many pharmacological activities such as anti-inflammatory; anti-bacterial; anti-hepatotoxic activities etc. Materials: In order to predict the pharmacological activity of Nigella Sativa’s compounds, some web based servers were used, namely, PubChem, Molinspiration, ADMET-SAR, PASS online and PharMapper. In addition to that, AutoDOCK was used to investigate the different molecular interactions between the selected compounds and their target proteins. Results: All compounds displayed a stable interaction with their targets and satisfactory binding energies, which means that they are active on their targets. Conclusion: Nigella sativa is an effective medicinal plant that has several ethno-medical uses; the latter uses are proven herein via an in-silico study of their pharmacological activities.Keywords: Nigella sativa, AutoDOCK, PubChem, Molinspiration, ADMET-SAR, PharMapper, PASS online server, docking
Procedia PDF Downloads 1342324 Development of Transparent Nano-Structured Super-Hydrophobic Coating on Glass and Evaluation of Anti-Dust Properties
Authors: Abhilasha Mishra, Neha Bhatt
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Super-hydrophobicity is an effect in which a surface roughness and chemical composition are combined to produce unusual water and dust repellent surface. The super-hydrophobic surface is widely used in many applications such as windshields of the automobile, aircraft, lens, solar cells, roofing, boat hull, paints, etc. Four coating solutions were prepared by varying compositions of 1,1,1,3,3,3 hexametyldisilazane (HDMS) and tetraethylorthosilicate (TEOS) sol. These solutions were coated on glass slides by a spin coating method and etched at a high temperature ranging 250 -350 oC. All the coatings were studied for its different properties like water repellent, anti-dust, and transparency and contact angle measurements. Stability of coatings was also studied with respect to temperature, external environment, and pH. It was found that all coatings impart a significant super-hydrophobicity on a glass surface with contact angle ranging from 156o to 162o and have good stability in the external environment. The results of the different coatings were observed and compared with each other. On increasing layers of coatings the super-hydrophobicity and anti-dust properties increases but after 3 coatings the transparency of coating starts decreasing.Keywords: super-hydrophobic, contact angle, coating, anti-dust
Procedia PDF Downloads 2592323 Utilization of Watermelon Rind Extract as Green Anti-Scalent for Cooling Water Systems
Authors: Elsayed G. Zaki, Nora A. Hamad, Hadeel G. El-Shorbagy
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The effect of watermelon rind extract as green inhibitors for the formation of calcium sulphate scale have been investigated using conductivity measurements concurrently with the scanning electron microscopy (SEM), and optical microscopic examinations. Mineral scales were deposited from the brine solution by cathodic polarization of the steel surface. The results show up that the anti-scaling property of the extracts could be attributed to the presence of citrulline. In solution, citrulline retards calcium sulphate precipitation via formation of a complex with the calcium cations. Thin, smooth and non adherent film formed over the steel surface, under cathodic polarization, by the deposition of the calcium- citrulline complex. The stability of the aqueous extracts with time was also investigated.Keywords: anti-scaling, scale inhibitor, green extracts, water treatment
Procedia PDF Downloads 274